Search

The aim of this study was to report on the compliance with follow-up among patients with thin melanomas. We also examined the prognosis of patients with recurrent disease and whether there were any differences in prognosis associated with the time between the last follow-up examination and the onset of recurrence. A retrospective analysis of the records of 513 consecutive patients (50.3% males, mean age: 52.8+/-16.9 years) with thin melanomas (

We analyze the discriminatory power of k-nearest neighbors, logistic regression, artificial neural networks (ANNs), decision tress, and support vector machines (SVMs) on the task of classifying pigmented skin lesions as common nevi, dysplastic nevi, or melanoma. Three different classification tasks were used as benchmarks: the dichotomous problem of distinguishing common nevi from dysplastic nevi and melanoma, the dichotomous problem of distinguishing melanoma from common and dysplastic nevi, and the trichotomous problem of correctly distinguishing all three classes. Using ROC analysis to measure the discriminatory power of the methods shows that excellent results for specific classification problems in the domain of pigmented skin lesions can be achieved with machine-learning methods. On both dichotomous and trichotomous tasks, logistic regression, ANNs, and SVMs performed on about the same level, with k-nearest neighbors and decision trees performing worse.

This paper considers estimation and inference in panel vector autoregressions (PVARs) with fixed effects when the time dimension is finite and the cross-sectional dimension is large. A Maximum Likelihood (ML) estimator based on a transformed likelihood function is proposed and shown to be consistent and asymptotically normal irrespective of the unit-root and cointegrating properties of the underlying PVAR model. This transformed framework is also used to derive unit-root and cointegration tests, based on standard chi-squared and normally distributed statistics, in panels with a short time dimension. It is shown that the standard Generalized Method of Moments (GMM) estimator, examined as an alternative to the proposed ML estimator, breaks down if the underlying time series contain unit roots. Also, the extended GMM estimator, using variants of homoskedasticity and stationarity restrictions as suggested in a univariate context, is subject to difficulties. Monte Carlo evidence suggests that the ML estimator and the tests of hypotheses and cointegration that are based on it perform well in small samples in marked contrast to the performance of GMM estimators.

A parametric study of the breakdown voltage of six commercially available thin polymer films before and after exposure to three gas plasmas was performed. Systematic changes of breakdown voltage were observed. This inexpensive and rapid gas treatment is a suitable method of increasing breakdown voltages in commercial polymer films. >

We have studied the electrical and optical characteristics of (AlGaIn)N multiple quantum well light-emitting diodes. Minimizing contact effects by utilizing platinum as p-contact metal, ideality factors as low as 1.1 have been achieved. In agreement with basic semiconductor theory, a correlation between ideality factor and small-current efficiency was found. We were able to emulate the experimental current-voltage characteristic over seven orders of magnitude utilizing a two diode model. This model enables a very good prediction of internal quantum efficiency at moderate current densities out of purely electrically derived parameters.

We investigate theoretically the influence of type and density of background carriers in the active region on the quantum efficiency of InGaN-based light emitters using an extension of the ABC rate model. A method to determine experimentally whether a certain type of Auger recombination is relevant in InGaN quantum wells is derived from these considerations. Using this approach, we show that the physical process which is the dominant cause for the efficiency droop is superlinear in the electron density and can thus be assigned to nnp-Auger recombination.

This paper develops a rational expectations life-cycle model designed as a framework for the cross-country analysis of (private) saving decisions. It is shown that a broad range of life-cycle models that have been used in the literature to study aggregate time series on consumption and saving fail to deliver plausible predictions for the purpose of analyzing saving decisions across countries as they imply that the level of saving has a constant mean and that the long-run saving rate may tend to zero. Introducing a utility specification that ties the long-run evolution of consumers' aspired consumption paths to that of aggregate labor income, an analytically tractable life-cycle model is proposed that has plausible long-run properties, including the implication that the net asset-labor income ratio, the saving rate, and the consumption-labor income ratio have meaningful long-run distributions. The moments of the long-run saving rate are shown to depend in a precise way on various characteristics of consumers' preferences, the real rate of interest, the growth rate and volatility of labor income, the government consumption-labor income ratio, and the government debt-labor income ratio. Employing a data set on saving rates and asset holdings across OECD economies and using techniques for the estimation of dynamic heterogeneous panels, the paper will also adduce empirical evidence assessing the model's ability to explain differences in the saving patterns across these economies.

To analyze the frequency and characteristics of enlarging common melanocytic nevi.Cohort study using digital epiluminescence microscopy (ELM) for documentation and follow-up, with a median follow-up interval of 11.4 months.A dermatology department at a university hospital in Vienna, Austria.One thousand six hundred twelve melanocytic nevi appearing clinically as common nevi, obtained from 385 patients (mean [+/-SD] age, 34.2 +/- 14.8 y; 55.6% female).Follow-up examination and documentation by digital ELM.Frequency of enlarging nevi according to age and comparison of ELM features observed in enlarging and nonenlarging nevi.Enlargement was found in 5.3% (n = 86) of nevi. The frequency of enlarging nevi was inversely related to age (P.001), in that enlarging nevi were common in patients younger than 20 years and relatively rare in older age groups. Epiluminescence microscopy revealed a peripheral rim of brown globules in 48.8% (n = 42) of enlarging nevi. In contrast, a peripheral rim of brown globules was found in only 0.7% (n = 11) of nevi without enlargement (P.001). Enlarging nevi that were excised in children and adolescents showed no histological signs of atypia. In older age groups, 48.1% of excised enlarging nevi that were clinically diagnosed as common nevi showed some histological signs of atypia. None of the excised enlarging lesions was histologically diagnosed as melanoma.The frequency of enlarging common nevi is inversely related to age. In the absence of clinical signs of atypia, enlargement alone does not indicate malignancy. A peripheral rim of brown globules is a characteristic ELM feature of symmetrically enlarging melanocytic nevi.

We use a data set of 1619 pigmented skin lesions images from three categories (common nevi, dysplastic nevi, and melanoma) to investigate the performance of four machine learning methods on the problem of classifying lesion images. The methods used were k-nearest neighbors, logistic regression, artificial neural networks, and support vector machines. The data sets were used to train the algorithms on the following tasks: to distinguish common nevi from dysplastic nevi and melanoma, and to distinguish melanoma from common nevi and dysplastic nevi. Receiver operating characteristic curves were used to summarize the performance of the models.

Surface properties of a number of commercial thermoplastic polymer films were investigated before and after brief exposures to RF induced, low temperature gas plasmas. Water wettability and adhesion of vapor deposited aluminum to thin films (8–12 micron) of polyethylene, polypropylene, polyester, polysulfone, polycarbonate, and polyvinylidene fluoride films were studied before and after treatments with oxygen, 96% CF4/4% O2, and helium plasmas. Treatment with oxygen plasmas showed the greatest change in water wettability for polyvinylidene fluoride and polypropylene films, while treatment with 96% CF4/4% O2 showed dramatic changes in wettability of polycarbonate, polysulfone, and polystyrene. Excellent adhesion of aluminium was found for polymers that had been previously exposed to gas plasmas.

Code for the article published in Handbook of Applied Econometrics: Macroeconomics, Oxford: Basil Blackwell, 1995, pp. 139–1. Currently, you may download one GAUSS- and one MATLAB program from this page. These programs, RBCQDE.PRG (GAUSS) and RBCQDE.M (MATLAB), solve the real business cycle model of Christiano and Eichenbaum (1992). (See the paper for further details.) To run the GAUSS program, you will also need to download the procedure MATPOW.G.(This abstract was borrowed from another version of this item.)

Objective: To assess the effects of nitroglycerin or urapidil on hemodynamic, respiratory and metabolic parameters in hypertensive patients with pulmonary edema. Design: Open, randomized and prospective clinical study. Setting: Out-of-hospital setting and Emergency Department in a 2000-bed hospital. Patients: Hundred twelve patients with evidence of hypertensive crises with pulmonary edema (systolic blood pressure (SBP) >200 mmHg and/or diastolic blood pressure (DBP) >100 mmHg and rales over both lungs) at the time when the emergency physician arrived. Interventions: The out-of-hospital treatment consisted of oxygen via face mask, 80 mg furosemide i. v., 10 mg morphium s. c., and either nitroglycerin sublingually (initial dose: 0.8 mg; repetitive administration of 0.8 mg every 10 min to a cumulative dose of 3.2 mg) or urapidil (initial dose: 12.5 mg i.v.; repetitive administration every 15 min to a cumulative dose of 50 mg). If SBP was more than 180 mmHg and/or DBP more than 90 mmHg on admission, antihypertensive treatment was continued with nitroglycerin (0.3–3 mg/h) or urapidil (5–50 mg/h). Measurements and results: Blood pressure (BP) was measured every 5 min with the use of an automatic oscillometric device. Serum lactate, PO2, pH value, and base excess (BE) were evaluated on admission and 6 h later. Blood pressure, serum lactate and BE on admission were significantly lower (SBP: 155±30 vs 179±33 mmHg; p=0.0002; DBP: 82±17 vs 93±19 mmHg; p=0.001; lactate: 2.2±1.6 vs 3.9±2.7; p=0.0001; BE: −1.9±3.9 vs −4.4±1.7; p=0.0005) and PO2 and pH values were significantly higher in the urapidil group compared to the nitroglycerin group (PO2: 75±25 vs 66±17; p=0.036; pH: 7.33±0.08 vs 7.29±0.09; p=0.042). After 6 h no differences between the two groups were observed. Conclusion: The more pronounced BP reduction in the urapidil group was associated with an improved respiratory and metabolic situation in hypertensive patients with pulmonary edema. Therefore, urapidil is a valuable alternative to nitroglycerin in patients with pulmonary edema and systemic hypertension.

Epiluminescence microscopy (ELM) is a non-invasive technique for in vivo examination which can provide additional criteria for the clinical diagnosis of pigmented skin lesions (PSLs). In the present study we attempt to determine whether PSLs can be automatically diagnosed by an integrated computerized system. This system should recognize the PSL, automatically extract features and use these features in training an artificial neural network, which should--if sufficiently trained--be capable of recognizing and classifying a new PSL without human aid. One hundred and twenty images of randomly selected histologically proven PSLs (33 common naevi, 48 dysplastic naevi and 39 malignant melanomas) were used in this study. The images were digitally obtained and the morphological features of the PSLs were extracted electronically without human assistance. The numerical data were then divided into learning and testing cases and linked to an artificial neural network for training and for further classification of lesions that the system had not been trained on. Our results show that the computerized system was able to automatically identify 95% of the PSLs presented. The sensitivity and specificity of the computerized system were 90% and 74% respectively. In contrast, when differentiating between individual types of lesions, the system performed at true positive rates of only 38% for malignant melanoma, 62% for dysplastic naevi and 33% for common naevi. Our data indicate that (1) ELM images of PSLs provide an excellent source for digital image analysis; (2) the vast majority of PSLs can be correctly identified by a relatively simple (and thus not "intelligent") application of digital image analysis; (3) automatic feature extraction based mainly on ABCD rules provides reliable data on the distinction between benign and malignant PSLs; and (4) there is evidence that artificial neural networks can be trained to adequately discriminate between benign and malignant PSLs.

The aim of this study was to examine the efficacy of lymph node palpation versus high resolution lymph node sonography for the detection of lymph node metastases in patients with malignant melanoma. We retrospectively evaluated 2256 pairwise lymph node examinations of the cervical, axillary and inguinal region by palpation and sonography in 264 patients with resected melanomas greater than 0.75 mm of invasion thickness. Lymph node metastases occurred in 50 patients (19%) which were detected in 38 (76%) by both methods in agreement. In 7 cases (14%) palpation failed, in 3 cases (6%) sonography failed and in 2 cases both methods failed to identify metastases. The overall sensitivity of detecting metastatic disease was 82% for palpation and 90% for sonography which was statistically not different. The overall specificity by sonography (99%) was significantly better than for lymph node palpation (88%). Taking into account the results of this analysis, we conclude that patients with a negative result by lymph node palpation do not need further sonography for verification. However, any suspect result by palpation should be additionally evaluated by lymph node sonography in order to rule in or out metastatic disease.

To assess the relationship between the sum of ST-segment elevations (ST score) in the admission ECG and the occurrence of early complications in patients with acute myocardial infarction (MI).We conducted an observational study of patients who presented with acute anterior or inferior MI to the ED of a 2,000-bed inner-city hospital. Age, sex, time from onset of pain and the start of thrombolysis, and ST score were evaluated by the emergency physician. "Early complications" were defined as acute congestive heart failure or severe rhythm disturbances in the 24 hours after the start of thrombolysis. The outcome measures were the relationship between ST score and the occurrence of early complications; the influence of age, sex, or time between onset of pain and thrombolysis; and identification of a cutoff value with the highest sensitivity and specificity for prediction of complications.We included 243 patients (194 men, 49 women; mean age, 56.6 years) with acute MI (anterior, 119; inferior, 124) who underwent thrombolysis in our analysis. ST score was significantly greater in patients with early complications, compared with patients without complications (anterior, 10.3 versus 19.4 mm [P.001]; inferior, 6.9 versus 10.4 mm [P.001]). Receiver-operator curve analysis revealed an ST score of 13 mm in patients with anterior MI and 9 mm in patients with inferior MI as the cutoff value with the greatest sensitivity and specificity for predicting early complications of MI. (For anterior MI, sensitivity was .79, specificity .73; for inferior MI, sensitivity was .64 and specificity .68.). On multivariate regression analysis, ST score was an independent predictor of the occurrence of at least one complication. (For anterior MI, the odds ratio [OR] was 9.7 and the 95% confidence interval [CI] 3.9 to 25.1; for inferior MI the OR was 5.0 and the 95% CI 2.0 to 12.8). Age, sex, and interval from onset of pain to treatment had no significant effect on the occurrence of early complications.The absolute ST score is useful in estimating the probability of early complications in patients with acute MI receiving thrombolytic therapy. A cutoff value of 13 mm for anterior MI and 9 mm for inferior MI stratifies patients into high- and low-risk subgroups for the development of acute congestive heart failure and severe rhythm disturbances during the first 24 hours of hospitalization.

Pigmented basal cell carcinoma (PBCC) is a tumour with distinct clinical features which occasionally may be difficult to differentiate from malignant melanoma (MM). The purpose of this study was to re-examine the epiluminescence microscopy (ELM) criteria for PBCC and to determine their statistical significance in the differential diagnosis of MM. Fifty histologically verified pigmented skin lesions (25 PBCCs and 25 MMs) were investigated using ELM for the presence of ELM criteria; their significance was determined by calculating the odds ratios. We found that individual ELM criteria have different weights of significance in the differential diagnosis of PBCC (leaf-like distribution of diffuse pigmentation, gradual thinning at the periphery and telangiectasia) and MM (pigment network, black and grey pigmentation, radial streaming, pseudopods, brown globules and black dots). Selected patterns of ELM criteria adjusted to the distinct types of pigmented skin lesions are characteristic features for preoperative diagnosis. The prevalence of distinct ELM criteria in PBCC and MM is of critical value in differentiating between the two types of lesions.

Objective: To assess the safety and efficacy of urapidil compared to sodium nitroprusside in the treatment of hypertensive emergencies. Design: randomized, prospective clinical study. Setting: Emergency department in a 2000-bed inner city hospital. Patients: Eighty-one patients with hypertensive emergencies defined as elevation of systolic blood pressure above 200 mmHg and/or diastolic blood pressure above 110 mmHg plus evidence of end-organ damage were included in the study protocol. The efficacy of therapy was defined as 1) blood pressure reduction below 180/95 mmHg within 90 min and 2) no re-elevation of blood pressure during a 4-h follow-up period in primary responders. The safety of both drugs was defined as the number of minor and major side effects during treatment. Interventions: Patients received either sodium nitroprusside (n = 35; continuous intravenous administration with a starting dose of 0.5 μg/kg per min; increase in increments of 0.5 μg/kg per min every 15 min until response to treatment or a maximum of 3 μg/kg per min) or urapidil (n = 46; intravenous bolus; starting dose: 12.5 mg; repetitive administration of 12.5 mg every 15 min until response or a maximum dose of 75 mg). Measurements and results: Blood pressure was measured every 2.5 min by using a non-invasive oscillometric blood pressure measurement unit. Response to treatment within 90 min was observed in 75 (93 %) patients (urapidil: n = 41 [89 %]; nitroprusside: n = 34 [97 %]; p = 0.18). During the follow-up period 8/34 (24 %) patients in the nitroprusside group and 1/41 (2 %) patients in the urapidil group exhibited blood pressure re-elevation. Major side effects were observed in seven patients receiving nitroprusside and two patients in the urapidil group (p = 0.04). Conclusion: Urapidil is equally effective, compared to sodium nitroprusside, in the treatment of hypertensive emergencies. Due to a smaller number of adverse events, urapidil is a reasonable alternative to nitroprusside in the treatment of hypertensive emergencies.

Experimental data suggest that postischemic blood glucose concentration plays an important role in modulating both ischemic cerebral infarction and selective neuronal necrosis. This study investigated the association between functional neurological recovery and blood glucose concentrations in human cardiac arrest survivors. A group of 145 nondiabetic patients were evaluated after witnessed ventricular fibrillation cardiac arrest. Data regarding cardiac arrest were collected according to an internationally accepted protocol immediately after arrival. Blood glucose was measured on admission and 6, 12, and 24 h thereafter. To control for duration of cardiac arrest and cardiogenic shock, both known to influence outcome as well as blood glucose, levels, Spearman rank partial correlation was used. In this multivariate analysis, a high admission blood glucose level tended to be associated with poor neurological outcome ( rs = −0.16, n = 142, p = 0.06). The association between high median blood glucose levels over 24 h and poor neurological outcome was strong and statistically significant ( rs = −0.2, n = 145, p = 0.015). High blood glucose concentrations occurring over the first 24 h after cardiac arrest have deleterious effects on functional neurological recovery. Whether cardiac arrest survivors might benefit from reduction of blood glucose levels needs further investigation.

Acute myeloid leukaemia (AML) is a major haematopoietic malignancy characterized by the proliferation of a malignant clone of myeloid progenitor cells. A reciprocal translocation, t(8;21)(q22;q22), observed in the leukaemic cells of approximately 40% of patients with the M2 subtype of AML disrupts both the AML1 (CBFA2) gene on chromosome 21 and the ETO (MTG8) gene on chromosome 8 (refs 3-5). A chimaeric protein is synthesized from one of the derivative chromosomes that contains the N terminus of the AML1 transcription factor, including its DNA-binding domain, fused to most of ETO, a protein of unknown function. We generated mice that mimic human t(8;21) with a "knock-in' strategy. Mice heterozygous for an AML1-ETO allele (AML1-ETO/+) die in midgestation from haemorrhaging in the central nervous system and exhibit a severe block in fetal liver haematopoiesis. This phenotype is very similar to that resulting from homozygous disruption of the AML1 (Cbfa2) or Cbfb genes, indicating that AML1-ETO blocks normal AML1 function. However, yolk sac cells from AML1-ETO/+ mice differentiated into macrophages in haematopoietic colony forming unit (CFU) assays, unlike Cbfa2-/- or Cbfb-/-cells, which form no colonies in vitro. This indicates that AML1-ETO may have other functions besides blocking wild-type AML1, a property that may be important in leukaemogenesis.

The purpose of the study was to evalute the impact of the renin-angiotensin-aldosterone (RAA) system on blood pressure (BP) response in patients with hypertensive emergencies and urgencies treated with intravenous enalaprilat. Thirty-five patients with a systolic BP (SBP)210 mm Hg and/or diastolic BP (DBP)110 mm Hg received 5 mg enalaprilat intravenously. The extent of systolic and DBP reduction was correlated with pretreatment concentrations of angiotensin II (ANGII) (SBP: r = -0.47; P = 0.006; DBP: r = -0.55; P = 0.001) and plasma renin activity (PRA) (SBP: r = -0.49; P = 0.003; DBP: r = 0.48; P = 0.007). Non-responders to enalaprilat exhibited significant lower pretreatment levels of PRA, angiotensin-converting enzyme (ACE) and ANG II compared to responders (PRA: 5.5 +/- 3.7 vs 1.1 +/- 2.2 ng/ml/h, P0.001; ACE: 12.8 +/- 3.5 vs 8.2 +/- 4.8 U/l, P = 0.003; ANG 11:8.7 +/- 6.2 vs 5.0 +/- 3.8 pg/ml, P = 0.04). In patients with severe hypotension following application of enalaprilat ANG II concentrations were significantly higher compared to patients with mean arterial BP reduction25% (12.3 +/- 6.7 vs 5.6 +/- 4.0 pg/ml,P = 0.013). These data indicate that PRA and ANG II are the major determinants for BP response to enalaprilat. This relation between BP response and RAA system activity have important clinical implications for the treatment of patients with severe hypertension. Primary therapeutic failure indicates that the RAA system contributes very little to the hypertensive status of the patient. Thus, repetitive application on an ACE inhibitor in primary responders is clinically unhelpful and may result in an unnecessary delay of an effective BP reduction. In contrast, high ANG II concentrations are associated with a considerable risk for severe hypotension after enolanalaprilat application. Therefore, the status of the RAA system determines the efficacy as well as the safety of ACE inhibitor treatment in patients with severe hypertension.

In this paper, the carrier transport in (Al)InGaN based test structures with In-rich quantum wells on c-plane substrates is investigated under high current operation. To get access to the injection efficiency, the devices are processed as ridge waveguide lasers and examined above threshold. The slope efficiency reveals a slight decrease as a function of current even under pulsed operation that can be related to a reduction of the injection efficiency based on carrier leakage. As the test structure contains an InGaN detection layer on the n-side, it is possible to verify hole overflow across the active region. Moreover, by analysing the current dependence of the radiative recombination in the detection layer, the reduction of slope efficiency can be correlated to increasing hole leakage.

We report on a green light-emitting device, in which the light of an efficient blue 1 mm2 GaInN/GaN light-emitting diode (LED) is converted into green light by an optically pumped GaInN/GaN multiple quantum well structure. This solution reached an efficacy of 127 lm/W, i.e., higher than that of state-of-the-art 1 mm2 GaInN/GaN LEDs emitting directly at the target wavelength, at 350 mA current and 535 nm peak wavelength. Optically pumped converters overcome the design limitations of typical multiple quantum well LEDs, where carrier transport issues limit the maximum number of functioning wells and might help to solve the problem of the green gap.

The CBFbeta subunit is the non-DNA-binding subunit of the heterodimeric core-binding factor (CBF). CBFbeta associates with DNA-binding CBFalpha subunits and increases their affinity for DNA. Genes encoding the CBFbeta subunit (CBFB) and one of the CBFalpha subunits (CBFA2, otherwise known as AML1) are the most frequent targets of chromosomal translocations in acute leukemias in humans. We and others previously demonstrated that homozygous disruption of the mouse Cbfa2 (AML1) gene results in embryonic lethality at midgestation due to hemorrhaging in the central nervous system and blocks fetal liver hematopoiesis. Here we demonstrate that homozygous mutation of the Cbfb gene results in the same phenotype. Our results demonstrate that the CBFbeta subunit is required for CBFalpha2 function in vivo.

Objectives.This study sought to evaluate the diagnostic value of the biochemical markers creatine kinase (CK), creatine kinase-MB fraction (CK-MB) and cardiac troponin T (cTNT) to diagnose acute myocardial infarction (AMI) after cardiopulmonary resuscitation (CPR).Background.Elevations of CK and CK-MB after CPR are a frequent finding and might be associated with ischemic myocardial injury, as well as physical trauma to the chest.Methods.Patients who had cardiac arrest and primary successful resuscitation were included in the study. The diagnosis of AMI was confirmed or ruled out by means of typical electrocardiographic findings, thallium-201 myocardial scintigraphy or autopsy, if death occurred during the hospital period, in 39 primary survivors of sudden cardiac death. In 24 patients (62%) the diagnosis of AMI was established. Serum cTNT, CK and CK-MB were measured, and the CK-MB/CK ratio was calculated on admission and after 12 h.Results.On admission all markers of myocardial injury proved to be weak methods for the diagnosis of AMI. After 12 h cTNT as well as CK-MB exhibited a similar diagnostic performance; CK and the CK-MB/CK ratio proved to be worthless. Sensitivity and specificity for a cTNT cutoff value of 0.6 ng/ml, 12 h after cardiac arrest, were 96% and 80%, respectively. For a CK-MB cutoff value of 26 U/liter, sensitivity was 96% and specificity was 73%.Conclusions.Cardiac TNT and CK-MB are valuable tools in detecting AMI as the cause of sudden cardiac death. However, there is a considerable lack of sensitivity and specificity. Cardiac injury is probably caused not only by AMI, but also by myocardial damage related to CPR efforts.

Objective : To evaluate the accuracy and reliability of noninvasive continuous finger blood pressure measurement in critically ill patients. Design : Prospective data collection. Setting : Emergency department in a 2,000-bed hospital. Patients : Thirty-nine patients admitted to the emergency department requiring invasive arterial blood pressure monitoring were enrolled to the study protocol. Interventions : Continuous noninvasive blood pressure measurement was performed on the middle phalanx of the second and third finger, using a test instrument which provides continuous arterial waveform display with the use of a finger cuff. Invasive mean arterial blood pressure measurement was done by cannulation of the radial artery and direct transduction of the systemic arterial pressure waveform. Measurements and Main Results : Three thousand one hundred eighteen pairs of simultaneous finger cuff and intra-arterial blood pressure measurements were collected in 1-min intervals from 39 patients over a total of 51.8 hrs. The overall discrepancy between both measurements was 0.10 mm Hg. The standard deviation of the differences was ±5.02 mm Hg. The mean bias in patients treated with catecholamines was 0.01 mm Hg and was not different from the bias observed in patients without catecholamines (mean bias : 0.23 mm Hg ; p >.22). Whereas 95% of all comparisons between finger cuff and intra-arterial measurement had a discrepancy ≤±10 mm Hg, 4.7% had a discrepancy between ± 10.1 to 15 mm Hg and 0.3% exhibited a discrepancy ≥±15 mm Hg. In 29 (74%) patients, the duration of errors >10 mm Hg was ≤1 min. In seven (18%) patients, the duration of errors >10 mm Hg was between 2 to 3 mins and in three (8%) patients, the errors lasted for >3 mins. Conclusions : Our data provide a guide to the accuracy and reliability of noninvasive finger blood pressure measurements in critically III patients. Although most test instrument measurements were reliable, in 8% of all patients large discrepancies (>10 mm Hg) between both measurements with a duration of >3 mins were noted. Concerning the considerable risk for arterial cannulation, our preliminary data demonstrate that the test instrument (PORTAPRES®, TNO Biomedical Instrumentation Research Unit ; The Netherlands) is an advance in noninvasive monitoring of critically ill patients and may be useful in most emergency clinical settings.

We evaluated the usefulness of a rapid, qualitative, bedside immunoassay for cardiac-specific troponin T in patients with chest pain. A concordant result between quantitative troponin T and qualitative troponin T assay was observed in 183 (96%) tests. The sensitivity of the rapid troponin T assay for detecting acute myocardial infarction increased significantly according to the number of hours elapsed after onset of chest pain from 17% for patients presenting within 4 h to 71% for patients presenting in the time interval of greater than 8 h from onset of chest pain (P0.001). Specificity ranged from 83 to 93% in the three time intervals evaluated. A concordant result between CK-MB-measurement and rapid troponin T assay was observed in 159 (83%) tests. In 14/191 tests a positive rapid troponin T and a negative CK-MB assay was observed. In 9/14 (64%) cases this result was true positive for the rapid troponin T assay and in 5/14 (36%) cases false negative. As sensitivity and specificity of the rapid troponin T assay are comparable with CK-MB measurements, rapid troponin T assay is a simple and useful laboratory tool for the bedside triage in patients with chest pain.

Preoperative assessment of melanoma invasion by sonometry has been reported to exhibit a high correlation with postoperative histometry based on the determination of a regression coefficient. We believe that this approach is not adequate and that it can be misleading. We therefore applied an appropriate statistical approach to our data to re-examine this issue. Preoperative measurements by sonometry were compared with postoperative histometry in 71 consecutive patients with the clinical diagnosis of malignant melanoma. Patients with the histological diagnosis of melanoma in situ (n = 13) were excluded from this comparison, as sonometry cannot distinguish structures restricted to the epidermis and Breslow thickness is not routinely determined in Clark level I melanomas. The agreement between sonometry and histometry was analysed by plotting the mean of the two methods against their difference. By linear regression analysis the correlation coefficient (r) in the invasive melanomas (n = 58) was found to be 0.92. The median thickness of the invasive tumours by sonometry was 1.36 mm, and by histometry 0.89 mm. In 95% of the cases sonometry differed by 37% above to 48% below the values obtained by histometry. Thus, we conclude that the accuracy of sonometry in predicting preoperative tumour thickness- and tumour invasiveness-is far lower than previously reported.

To summarize biochemical failure rates and morbidity of external beam irradiation (EBRT) combined with palladium (103Pd) boost for clinically localized high-risk prostate carcinoma.Seventy-three consecutive patients with stage T2a-T3 prostatic carcinoma were treated from 1991 through 1994. Each patient had at least one of the following risk factors for extracapsular disease extension: Stage T2b or greater (71 patients), Gleason score 7-10 (40 patients), prostate specific antigen (PSA)15 (32 patients), or elevated prostatic acid phosphatase (PAP) (17 patients). Patients received 41 Gy EBRT to a limited pelvic field, followed 4 weeks later by a 103Pd boost (prescription dose: 80 Gy). Biochemical failure was defined as a PSA greater than 1.0 ng/ml (normal4.0 ng/ml). Patients whose PSA was still decreasing at the last follow-up were censored at that time. Patients whose PSA plateaued at a value greater than 1.0 were scored as failures at the time the PSA first plateaued.The overall, actuarial freedom from biochemical failure at 3 years after treatment was 79%. In Cox proportional hazard multivariate analysis, the strongest predictor of failure was elevated acid phosphatase (p = 0.04), followed by PSA (p = 0.17), Stage (p = 0.23), and Gleason score (p = 0.6). Treatment-related morbidity was usually limited to temporary, RTOG Grade 1-2 urinary symptoms. One patient, who had both a transurethral incision of the prostate (TUIP) and a transurethral resection of the prostate (TURP), developed low-volume urinary incontinence. The actuarial potency rate at 3 years after implantation was 77% for 46 patients who were sexually potent prior to implant.Biochemical freedom from failure rates following combined EBRT and 103Pd brachytherapy for clinically localized, high-risk prostate cancer compare favorably with that reported after conventional dose EBRT alone. Morbidity has been acceptable.

The CBFA2 (AML1) gene encodes a DNA-binding subunit of the heterodimeric core-binding factor. The CBFA2 gene is disrupted by the (8;21), (3;21), and (12;21) chromosomal translocations associated with leukemias and myelodysplasias in humans. Mice lacking a CBF alpha 2 protein capable of binding DNA die between embryonic days 11.5 and 12.5 due to hemorrhaging in the central nervous system (CNS), at the nerve/CNS interfaces of cranial and spinal nerves, and in somitic/intersomitic regions along the presumptive spinal cord. Hemorrhaging is preceded by symmetric, bilateral necrosis in these regions. Definitive erythropoiesis and myelopoiesis do not occur in Cbfa2-deficient embryos, and disruption of one copy of the Cbfa2 gene significantly reduces the number of progenitors for erythroid and myeloid cells.

Background and Purpose In animal cardiac arrest studies, outcome has been improved by inducing arterial hypertension early after return of spontaneous circulation. The aim of our study was to evaluate whether arterial blood pressure within the first minutes and hours after return of spontaneous circulation influences neurological recovery in human cardiac arrest survivors. Methods Of 136 retrospectively evaluated patients after sudden cardiac death, two groups were defined: group 1, mean arterial blood pressure (MABP) within 5 minutes after return of spontaneous circulation above 100 mm Hg; group 2, MABP of 100 mm Hg or less. Thereafter MABP was measured every 5 minutes until 2 hours after return of spontaneous circulation. The groups were compared in regard to age, sex, in/out of hospital, witnessed/not witnessed, first electrocardiographic rhythm, time from cardiac arrest to beginning of life support and to return of spontaneous circulation, cumulative epinephrine dose administered, and best neurological outcome within 6 months. Results In group 1 (n=54) good neurological recovery was observed in 63% and in group 2 (n=82) in 55% (χ 2 =0.87, P =NS). Both groups exhibited comparable baseline values except that time intervals from beginning of life support to return of spontaneous circulation were shorter in group 1. After we controlled for this difference with Spearman’s partial rank correlation ( r s ), there was no association between MABP measured within the first 5 minutes and outcome ( r s =−.023; P =NS). Good neurological recovery was independently and directly related to MABP measured during 2 hours after return of spontaneous circulation ( r s =.26; P Conclusions In human cardiac arrest survivors, good functional neurological recovery was independently and positively associated with arterial blood pressure during the first 2 hours after human cardiac arrest but not with hypertensive reperfusion within the first minutes after return of spontaneous circulation.

Rationale Coloring with patent blue V is a standard method in identifying the draining sentinel lymph node in melanoma skin cancer and breast cancer patients. We describe a case of anaphylaxis with 10 minutes cardiac arrest requiring mechanic cardio-pulmonary reanimation measures after the intradermal administration of patent blue V in a melanoma patient. The patients survived the incident without any sequelae. Methods One month after the incident, in vitro (RAST, total IgE, serum tryptase, ELISA for IgE binding to patent blue V) as well as in vivo (prick and intradermal skin test) tests were performed. Results A positive intradermal test to patent blue V and the patent blue derivative isosulfan blue at a dilution of 1:10000 confirmed the specificity of the anaphylactic reaction. While an experimental RAST revealed normal values, there was a high IgE signal to patent blue V and isosulfan blue in an experimental ELISA system. Sera from healthy controls showed only low signal intensity. Other allergies were excluded based on negative history, skin and standard in vitro tests. Conclusions To our knowledge, this is the first demonstration of IgE binding in a very severe case of anaphylaxis to patent blue V.

Circulating levels of extracellular matrix components were measured by radioimmunoassays and tested if they were useful for clinical staging in chronic heart failure. In 41 patients with dilated cardiomyopathy (33 idiopathic and 8 ischemic cases), the serum concentrations of procollagen type III aminoterminal peptide (PIIINP), type I collagen telopeptide (ICTP), and basement membrane laminin were significantly higher than in 30 healthy controls regardless of the underlying etiology. Patients with serum values of PIIINP, ICTP, and laminin > 7 micrograms/L, 7.6 micrograms/L, and 2.3 U/ml, respectively, were at higher relative risk for advanced clinical stage, poor hemodynamic condition, hyponatremia, heart transplantation, and death during follow-up than patients with low levels, with the exception that serum laminin > 2.3 U/ml was not significantly associated with hyponatremia and heart transplantation. Despite their interdependence on liver function, circulating levels of PIIINP and ICTP were independent predictors of mortality. In 17 of the 41 patients with cardiomyopathy whose explanted hearts were available for histologic evaluation, serum PIIINP, ICTP, and laminin significantly correlated with the myocardial area fractions of their tissue analogues (PIIINP vs myocardial collagen type III, r = 0.784, p = 0.0013; serum ICTP vs myocardial collagen type I, r = 0.603, p = 0.0527; and serum laminin vs myocardial laminin, r = 0.605, p = 0.0411). In conclusion, the increase in extracellular matrix turnover, which may partially be derived from fibrosis in the myocardium, can be measured in the serum of patients with dilated cardiomyopathy, and has an impact on risk stratification and prognosis.

High-efficiency InGaN-based light-emitting diodes have been grown on (111) silicon substrates and investigated with regard to efficiency and carrier lifetime as a function of current density. Using a single quantum well active layer ensures a well-defined active volume which enables the precise determination of the recombination coefficients in the ABC rate model for different emission wavelengths and junction temperatures. Good agreement of the resulting C values with calculated Auger coefficients is found both with respect to absolute value as well as their dependence on bandgap energy and temperature.

A wide range of somatic symptoms of the perimenopausal female is due to the decrease of estrogen at that age. Minor attention has been paid hitherto to the involvement of estrogens in female skin ageing symptoms. In our study, the ageing skin of the face of perimenopausal females was treated with a 0.3% estriol cream (8 patients) or with a 0.01% estradiol cream (10 patients) for 6 months. Dermatologic follow-up was performed monthly. At each follow-up venous blood for radioimmuno assay determination of prolactin (PRL), follicle stimulating hormone (FSH) and estradiol (E2) was sampled. In addition, prior to and after 3 and 6 months of treatment, gynecological examinations for climacteric symptoms, mammary and colposcopic investigations and vaginal smears for cytology were performed. Both treatment groups showed improvement of the various skin ageing symptoms at the end of treatment. The effects of the group treated with topical estriol were slightly superior with regard to their extent and onset. No hormonal side effects were noted either clinically or by hormone monitoring. According to these preliminary results, local estrogen treatment appears to be a promising new approach for the treatment of skin ageing in perimenopausal females. However, for minimizing the risk of systemic hormonal side effects, concentrations and size of application field should be limited.

Summary In vivo epiluminescence microscopy (ELM) is a non-invasive technique which improves the clinical diagnosis of naevi and malignant melanoma by providing diagnostic criteria that cannot be appreciated by the naked eye. The present study investigated whether ELM criteria pattern analysis can be employed in an objective, observer-trained, computer-aided diagnostic system, and whether artificial neural networks (ANN) can be applied to the diagnosis of pigmented skin lesions (PSL). The ELM criteria patterns of 200 PSL oil immersion images (60 common naevi, 60 dysplastic naevi, and 80 malignant melanomas) were analysed using a standardized questionnaire. One hundred randomly assigned PSL were used as a training set for an ANN, the remaining 100 PSL serving as the test set. The ANN was trained by backward propagation according to the histological diagnosis, and its performance was compared with that of human investigators. Out of the test set the human investigators correctly diagnosed 88% of PSL and the ANN 86%. in a dichotomized model comparing common, compound, and dysplastic naevi vs. malignant melanoma, i.e. benign vs. malignant PSL, the sensitivity and specificity of human diagnosis was 95 and 90%, respectively, whereas the sensitivity and specificity of the ANN diagnosis was 95 and 88%. Our data indicate that artificial neural networks can be trained to diagnose PSL at a human expert level, based on patterns provided by ELM criteria. We suggest that this technique offers a new approach to the diagnosis of PSL.

Background : Epiluminescence microscopy (ELM) is a noninvasive technique by which the clinical diagnosis of pigmented skin lesions (PSL) can be improved. Many ELM criteria have been described, but their significance in the differential diagnosis of PSL has not yet been established. Objective : The purpose of this study was to determine the value of ELM criteria in the differential diagnosis of PSL. Methods : Two hundred one melanocytic PSL (61 common nevi, 60 dysplastic nevi, and 80 melanomas) were investigated with ELM for the presence of certain ELM criteria; their significance was determined by calculating the odds ratios. Results : Individual ELM criteria have different weights of significance in the differential diagnosis of melanocytic PSL. Selected patterns of ELM criteria adjusted to the distinct types of PSL considerably improve the diagnostic accuracy of melanocytic PSL. Conclusion : The prevalence of certain distinct ELM criteria in a given melanocytic PSL has statistical value in differential diagnosis.

Steady-state and transient computer models of the RL10A-3-3A rocket engine have been created using the Rocket Engine Transient Simulation (ROCETS) code. These models were created for several purposes. The RL10 engine is a critical component of past, present, and future space missions; the model will give NASA an in-house capability to simulate the performance of the engine under various operating conditions and mission profiles. The RL10 simulation activity is also an opportunity to further validate the ROCETS program. The ROCETS code is an important tool for modeling rocket engine systems at NASA Lewis. ROCETS provides a modular and general framework for simulating the steady-state and transient behavior of any desired propulsion system. Although the ROCETS code is being used in a number of different analysis and design projects within NASA, it has not been extensively validated for any system using actual test data. The RL10A-3-3A has a ten year history of test and flight applications; it should provide sufficient data to validate the ROCETS program capability. The ROCETS models of the RL10 system were created using design information provided by Pratt & Whitney, the engine manufacturer. These models are in the process of being validated using test-stand and flight data. This paper includes a brief description of the models and comparison of preliminary simulation output against flight and test-stand data.

Space vehicle propulsion systems are traditionally comprised of a cluster of discrete engines, each with its own set of turbopumps, valves, and a thrust chamber. The Integrated Modular Engine (IME) concept proposes a vehicle propulsion system comprised of multiple turbopumps, valves, and thrust chambers which are all interconnected. The IME concept has potential advantages in fault-tolerance, weight, and operational efficiency compared with the traditional clustered engine configuration. The purpose of this study is to examine the steady-state performance of an IME system with various components removed to simulate fault conditions. An IME configuration for a hydrogen/oxygen expander cycle propulsion system with four sets of turbopumps and eight thrust chambers has been modeled using the Rocket Engine Transient Simulator (ROCETS) program. The nominal steady-state performance is simulated, as well as turbopump thrust chamber and duct failures. The impact of component failures on system performance is discussed in the context of the system's fault tolerant capabilities.

Approximately 50% of iuliu mice have situs incersus (mirror image reversal of viscera) and 40% have heterotaxia (anomalous arrangement of viscera). The occurrence of heterotaxia is independent of situs. Using the cross-intercross breeding system to put the iv gene on the SWV background, an occasional presumed iuli mouse was found that had an IV (situs inucrsus and/or heterotaxic) phenotype. Testcrosses of these reversed animals indicated an iui t genotype. Since iv is linked tightly to Igh-C on chromosome 12, we inferred the genotype with a polymorphism of Igh-C demonstrated using the polymerase chain reaction (PCR). This confirmed them to be ivi + . The expression of the IV phenotype in animals heterozygous for the tu gene may be due to an interaction of iv with an autosomal recessive gene found in SWV. We have not found the IV phenotype in heterozygous iui + mice following placement of the it, gene on six other inbred strains. Rarely, we also found that presumed SWV + + mice had the IV phenotype. Test matings of these phenodcviants, corroborated by PCR, have confirmed them to be +I + . Although the phenotypes of the affected SWV +I + and ivl + mice resembled those found in iviiu mice, the occurrence of situs inversus and heterotaxia were not independent of each other, and most, of the SWV mice with the IV phenotype had heterotaxia with situs solitus. This infrequent. dominant expression of the iv gene has so far only been seen when iv is on the SWV background. These findings are consistent with the idea that this phenomenon is due to the interaction of the iv gene with another gene found so far only in the SWV strain. (~8 1993 Wiley-Liss, Inc. The autosomal recessive gene iu (Hummel and Chapman, '59), which maps to chromo- some 12 (Brueckner et al., '89), causes situs inuersus (mirror image reversal of place- ment of organs) in mice. One half of iuliu mice have situs inuersus and approximately 40% have some sort of heterotaxia, an ab- normal arrangement of organs in relation to each other. Heterotaxia occurs indepen- dently of visceral situs in ivliv mice, so that the frequency of heterotaxia in mice with situs inversus is equal to its frequency in those with situs solitus (normal placement of organs). In mouse strains examined pre- viously, ivl + heterozygotes have demon- strated normal laterality indicating that the iu gene is a loss-of-function allele: in the absence of iu gene activity in the ii)!ii$ mouse, laterality determination does not oc- cur resulting in the random determin a t' ion of visceral .situs (Layton, '76; Kurnit et al., '87).

Background: Pigmented Spitz nevi have distinct clinical features but often may be difficult to differentiate from malignant melanoma by clinical criteria. Objective: The purpose of this study was to use a new noninvasive diagnostic approach to improve the clinical diagnosis of Spitz nevi. Methods: Epiluminescence microscopy (ELM) is a new, noninvasive technique for which criteria for the diagnosis of melanocytic tumors, benign and malignant, recently have been established. These criteria were tested in an investigation of 54 pigmented Spitz nevi. Results: With ELM the accuracy of clinical diagnosis of pigmented Spitz nevi improved from 56% (clinical) to 93% (ELM). Conclusion: Our findings suggest that ELM criteria are useful to improve the accuracy of clinical diagnosis of Spitz nevi.

At present, tumor invasion represents the most reliable prognostic factor for primary malignant melanoma. The 10-year survival rate of "thin" melanomas (Breslow less than 0.76 mm) is more than 95%, but approximately 5% of these low-risk tumors do metastasize. In an attempt to determine prognostic markers for "thin" melanomas we investigated the volume-weighted mean nuclear volume (Vv) of primary melanomas with tumor invasions below 0.76 mm in 32 patients. Ten of these patients had developed melanoma metastases within a mean follow-up period of 49 months; 22 patients who had not developed metastases and who were comparable with regard to clinical and histologic criteria as well as to follow-up period were selected as a comparison group. Vv was determined by computer-assisted image analysis (IBAS 20, Kontron, Germany) on hematoxylin-eosin-stained sections employing stereologic estimation of the volume-weighted mean nuclear volume. In addition, two-dimensional morphometric parameters (nuclear area and shape factors) as well as clinical (sex, age, location) and histologic characteristics (Breslow's thickness, Clark's level, and growth patterns) were recorded. The mean Vv (+/- SD) of primary melanomas with subsequent metastatic course was 273 microns 3 (+/- 81.3), whereas primary melanoma lesions without subsequent metastases exhibited a significantly lower Vv of 154 microns 3 (+/- 25.3) (p = 0.0008). On the other hand, two-dimensional morphometric and clinical and histologic parameters did not correlate with prognosis. Vv thus seems to represent a powerful and independent prognostic marker for "thin" primary melanomas. Assessment of Vv may provide a valuable tool in selecting patients with high-risk stage I, Breslow less than 0.76 mm, melanoma for adjuvant therapy.

Researchers at NASA Lewis Research Center are presently developing qualitative modeling techniques for automated rocket engine diagnostics. A qualitative model of a turbopump interpropellant seal system has been created. The qualitative model describes the effects of seal failures on the system steady-state behavior. This model is able to diagnose the failure of particular seals in the system based on anomalous temperature and pressure values. The anomalous values input to the qualitative model are generated using numerical simulations. Diagnostic test cases include both single and multiple seal failures.

The 18th Army Science Conference was held at the Hyatt Hotel, Orlando, Florida, 22-25 June 1992. The conference presented a cross section of the many significant scientific and engineering programs carried out by the Department of the Army (DA). Additionally, it provided an opportunity for DA civilian and military scientists and engineers to present the results of their research and development efforts before a distinguished and critical audience.

Solaris™ 2.0 ist die nachste Generation der Distributed Computing Losung von SunSoft™ und hat System V Release 4 als Grundlage. Solaris 2.0 setzt sich aus SunOS™ 5.0, erweitertem ONC™, OpenWindows™ V3, DeskSet™ V3 und OPEN LOOK* zusammen. Gewappnet mit der Leistungsfahigkeit des fuhrenden Multitasking- und Multiprocessing-Betriebssystems mit erweiterten Netzwerkfunktionen stellt Ihnen Solaris 2.0 die leistungsfahigste — und intuitivste — graphische Benutzeroberflache zur Verfugung, die jemals entwickelt wurde.