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Aims The outcome of chordoma patients with local or distant failure after proton therapy is not well established. We assessed the disease-specific (DSS) and overall survival of patients recurring after proton therapy and evaluated the prognostic factors affecting DSS. Materials and methods A retrospective analysis was carried out of 71 recurring skull base (n = 36) and extracranial (n = 35) chordoma patients who received adjuvant proton therapy at initial presentation (n = 42; 59%) or after post-surgical recurrence (n = 29; 41%). The median proton therapy dose delivered was 74 GyRBE (range 62–76). The mean age was 55 ± 14.2 years and the male/female ratio was about one. Results The median time to first failure after proton therapy was 30.8 months (range 3–152). Most patients (n = 59; 83%) presented with locoregional failure only. There were only 12 (17%) distant failures, either with (n = 5) or without (n = 7) synchronous local failure. Eight patients (11%) received no salvage therapy for their treatment failure after proton therapy. Salvage treatments after proton therapy failure included surgery, systemic therapy and additional radiotherapy in 45 (63%), 20 (28%) and eight (11%) patients, respectively. Fifty-three patients (75%) died, most often from disease progression (47 of 53 patients; 89%). The median DSS and overall survival after failure was 3.9 (95% confidence interval 3.1–5.1) and 3.4 (95% confidence interval 2.5–4.4) years, respectively. On multivariate analysis, extracranial location and late failure (≥31 months after proton therapy) were independent favourable prognostic factors for DSS. Conclusion The survival of chordoma patients after a treatment failure following proton therapy is poor, particularly for patients who relapse early or recur in the skull base. Although salvage treatment is administered to most patients with uncontrolled disease, they will ultimately die as a result of disease progression in most cases.

Prospective systematic analyses of the clinical presentation of bullous pemphigoid (BP) are lacking. Little is known about the time required for its diagnosis. Knowledge of the disease spectrum is important for diagnosis, management and inclusion of patients in therapeutic trials.The primary aims of the study were: (i) to characterize the clinical features of BP at time of diagnosis; and (ii) to assess the diagnostic delay in BP and its impact on prognosisAll new cases of BP diagnosed in Switzerland between 1 January 2001 and 31 December 2002 were prospectively registered by means of a standardized data collection form.One hundred-seventeen patients with BP were included in the study. 97cases (82.9%) had typical features with vesicles, blisters and/or erosions at time of diagnosis, while in the remaining cases (17.1%) only excoriations, eczematous and/or urticarial infiltrated lesions were observed. Head/neck as well as palmo-plantar involvement were found in up to 20% of patients, while mucosal lesions were present in 14.5% of the cases. Diagnosis was made after a mean of 6.1 months after the first symptoms. In patients, in whom the diagnostic delay was 4 months or more (defined as late diagnosis group), lesions were more often limited to one body area. The type of lesions did not affect the diagnostic delay. Diagnosis was made more rapidly in patients with limb involvement compared to those without. The calculated mortality rate in the early and late diagnosis group was 18.9% and 17.9%, respectively, without significant difference.BP often presents with bullous lesions at time of diagnosis after a mean diagnostic delay of 6 months. Nevertheless, up to 20% of patients lack obvious blistering and postbullous erosions, mimicking thus a variety of inflammatory dermatoses. Localized disease is associated with an increased diagnostic delay, which has however no impact on prognosis.

Most of the time, blood samples must be taken by syringe from radial, humeral or femoral artery in order to measure the arterial blood gas. These blood tests can be also carried out directly through an arterial catheter. The correct way to do a reliable blood test for measuring blood gas is now well established (5, 10), and must be respected if we are to have trustworthy results. Choosing the right equipment is one of the main pre-analytical criteria.In this work, the blood gasometry results obtained by 3 types of syringes were compared with a sample of 27 patients.In this study, the practicalities and the safety aspects of the 3 syringes were the same. There were statistically different values for blood gas measurements between the 3 syringes.For the electrolytes Na+ and K+, Bayer heparin saturated and Bayer heparin reduced syringes seemed to be more reliable. This was not the case for Ca2+ although many publications (2, 11, 12,) have shown the sensitivity of this ion to anticoagulants.The Becton...

In general, blood gas analysers can also determine the value of haematocrite by measuring the blood's conductivity. The question to ask is whether this value is reliable. In this study, hematocrit obtained via conductivity from 6 different pieces of equipment were compared with those measured using the gold standard method, which is microcentrifugation. By interpreting the results of 320 arterial blood samples taken in the intensive care unit DAR "B" we can see that the reliability between two measurements on the same piece of equipment is very good, in general > 0.95 whatever the equipment. The reliability between the means of the two measurements and the gold standard is slightly lower but remains very satisfactory, most often between 0.8 and 0.9. The Gem Premier 3000 (IL) analyser and the Roche OMNI S gave the best reliability compared with centrifugation. The Spearman coefficients between the mean values of the analysers and those of centrifugation were high, with the exception of the Rapidpoint 405. They are all statistically different from zero (p

Background and objectives: This cross-sectional, epidemiological study sought to assess the prevalence and extent of potential risk factors for hypertension, particularly renal function related to haematuria and their associations in people with haemophilia. Methodology: Demographic and medical data were collected at a single time-point in patients with haemophilia over 40 years of age from 16 European centres. Associations with diagnosis of hypertension were tested in univariate and multivariate analyses. Results: We enrolled 532 patients (median age 52 years, range 40-98) with haemophilia A (n = 467) or haemophilia B (n = 65). Haemophilia was severe (-1) in 313 patients (59%). Hypertension was diagnosed in 239 patients (45%). In multivariate analyses, age and body mass index (BMI) were significantly and independently associated with hypertension (adjusted odds ratio (OR) 18.1, P 30 kg m-2). Estimated glomerular filtration rate (eGFR) -1 (OR = 2.7, P = 0.047) was significantly associated with hypertension, but mean eGFR was significantly higher for severe than mild haemophilia. Further variables with OR > 2.8 were diabetes (OR = 2.8, P = 0.04), coronary artery disease (OR = 3.3, P = 0.052) and family history of hypertension (OR = 4.4, P

Background: We conducted an economic analysis of a phase III clinical trial comparing sequential radiochemotherapy (RT-CT) with concurrent RT-CT in patients with locally advanced non-small-cell lung cancer. Patients and methods: The trial was a randomized multicenter study comparing three cycles of chemotherapy (arm A) followed by radiotherapy against an RT-CT combination (two cycles of platinum etoposide) followed by two cycles of platinum-vinorelbine (arm B). The economic analysis adopted the payer's perspective and only included direct costs. Costs (€, 1996–2003) were recorded until the cut-off date. A cost minimization analysis and a sensitivity analysis were carried out. Results: Data from 173 patients were used in the economic study. Protocol costs tended to be higher in arm B, while relapse costs were significantly higher in arm A. The total number of hospital days was higher in arm B. The average total cost per patient was €16 074 in arm A and €15 245 in arm B (P = 0.15). The cost minimization analysis favored arm B. This advantage persisted in the sensitivity analysis. Conclusions: Concurrent RT-CT was not the more costly strategy in this phase III trial, despite lengthier hospitalization for toxicity. Other studies of similar design are needed to confirm these results in future randomized trials.

In studies of disease states and their relation to evolution, data on the state are usually obtained at in frequent time points during follow-up. Moreover in many applications, there are measured covariates on each individual under study and interest centres on the relationship between these covariates and the disease evolution. We developed a continuous-time Markov model with use of time-dependent covariates and a Markov model with piecewise constant intensities to model asthma evolution. Methods to estimate the effect of covariates on transition intensities, to test the assumption of time homogeneity and to assess goodness-of-fit are proposed. We apply these methods to asthma control. We consider a three-state model and we discuss in detail the analysis of asthma control evolution. Copyright © 2003 John Wiley & Sons, Ltd.

Nitrous oxide, together with aluminium and silicon chlorides, as precursor gases, while hydrogen and nitrogen as carriers, have been fed into a cold-wall reactor, in order to produce crystalline deposited layers of mullite (3Al 2 O 3 .2SiO 2 ) on silicon carbide and aluminium nitride substrates. The corresponding deposition kinetics has been studied, for fixed flow rates of nitrous oxide, hydrogen and nitrogen, as a function: of the substrate temperature, from 1100 to 1300 °C; of the gas pressure, from 10 to 90 hPa and of the AlCl 3 to SiCl 4 input ratio.The coating's chemical composition, crystal structure and morphology was precisely determined by means of WDS, XRD and SEM. The aluminium content of the deposits increases first as a function of pressure. It reaches a maximum for P = 20 hPa, whence it decreases steadily, to finally vanish completely for P = 100 hPa. The best experimental conditions to produce mullite coatings were then interpolated, experimentally tested, and the side compounds, under such conditions, identified.

Codeposits of AlN and Si 3 N 4 nitrides are obtained by low pressure chemical vapour deposition (LPCVD) in a hot-wall reactor using AlCl 3 , SiC 4 and NH 3 as precursors. The AlCl 3 is prepared by action of SiCl 4 on an aluminium supply, heated at 520 °C. The nitrogen is used as a carrier gas. The deposits are made at the temperature of 1100 °C and at a total pressure of 133 Pa, on graphite substrates covered with SiC. By modifying the gas phase composition in AlCl 3 and SiCl 4 , a mixture of two phases AlN and Si 3 N 4 in various proportions is obtained. The codeposits were characterized by: X-ray diffraction, WDS, XPS and Auger.

β-SiC polycrystalline layers were grown by MOCVD in a hot-wall reactor using tetramethylsilane (TMS). The dependence of the kinetics of deposition on the temperature and the TMS partial pressure was obtained. Gas-phase homogeneity inside the reactor was studied. Thermodynamic calculations on the thermal decomposition of TMS were performed.

Thermodynamical calculations on tetramethylsilane (TMS) pyrolysis were performed in order to study the evolution of ethylene and acetylene partial pressures as a function of the experimental conditions. The different preferential orientations of the deposited SiC films are correlated with the variation of the partial pressure of these byproducts.

A poor biological response to clopidogrel is associated with an increased risk of major cardiovascular ischemic events (MACE). Paraoxonase 1 (PON1) enzyme activity is modulated by the PON1-Q192R variant (rs662) and was recently suggested to be strongly involved in clopidogrel bioactivation, but the influence of the PON1-Q192R variant on the risk of MACE in clopidogrel-treated patients is controversial.To determine whether the PON1-Q192R variant influences clopidogrel biological responsiveness and the risk of MACE in patients treated with clopidogrel.Systematic review and meta-analysis of studies of the association between the PON1-Q192R polymorphism and the biological response to clopidogrel and/or the risk of MACE during clopidogrel administration.Seventeen studies were included. In the 12 studies of the biological response to clopidogrel (n = 5302 patients), there was no significant difference between 192QQ and 192QR + 192RR subjects, whatever the laboratory method used (global mean standardized difference = 0.10 [-0.06; 0.25], P = 0.22). Eleven studies assessed the risk of MACE, four using a case-control design (n = 2739 patients) and seven a prospective design (n = 5353 patients). Overall, MACE occurred in 19% of patients in case-control studies and in 6% of patients in prospective cohort studies, with no significant difference between 192QQ and 192QR + 192RR patients (OR = 1.28 [0.97; 1.68], P = 0.08). Similar results were obtained when study design was taken into account. Heterogeneity was mainly driven by one publication.This meta-analysis suggests that the PON1-Q192R polymorphism has no major impact on the risk of MACE and does not alter the biological response to clopidogrel in clopidogrel-treated patients.

AlN deposits, prepared by low-pressure chemical vapour deposition (LPCVD), with or without N2O addition in the source gases, have been examined by several complementary transmission electron microscopy (TEM) techniques, including electron diffraction (ED), high-resolution electron microscopy (HREM), electron energy loss and extended energy loss fine structure spectroscopies (EELS and EXELFS), to determine both the structures and local chemical compositions. The major differences between the compounds lie in the occurrence of micro- and nanostructural changes, as dendrites and extended defects. It is suggested that the observed structural changes are induced by oxygen impurities. The implications of the results for the interpretation of some physical properties of the compounds are discussed in terms of these changes.

Birth is the first haemostatic challenge for a child with haemophilia. Our aim was to examine the association between perinatal risk factors and major neonatal bleeding in infants with haemophilia. This observational cohort study in 12 European haemophilia treatment centres (HTC) incorporated 508 children with haemophilia A or B, born between 1990 and 2008. Risk factors for bleeding were analysed by univariate analysis. Head bleeds occurred in 18 (3·5%) children within the first 28 d of life, including three intraparenchymal bleeds, one subdural haematoma and 14 cephalohaematomas. Intra-cranial bleeds were associated with long-term neurological sequelae in two (0·4%) cases; no deaths occurred. Assisted delivery (forceps/vacuum) was the only risk factor for neonatal head bleeding [Odds Ratio (OR) 8·84: 95% confidence interval (CI) 3·05-25·61]. Mild haemophilia and maternal awareness of her haemophilia carrier status seemed to be protective (OR 0·24; 95%CI 0·05-1·05 and OR 0·34; 95%CI 0·10-1·21, respectively), but due to the low number of events this was not statistically significant. We found no association between neonatal head bleeding and country, maternal age, parity, gestational age or presence of HTC. Maternal awareness of carrier status protected against assisted delivery (unadjusted OR 0·37; 95%CI 0·15-0·90; adjusted OR 0·47 (95%CI 0·18-1·21).

Using new sensitive quantitative polymerase chain reaction (PCR) assays, cytomegalovirus (CMV) DNA is often detectable in the plasma of immunosuppressed patients. We investigated the prognostic value of a positive CMV DNA test for the development of CMV end-organ disease, other AIDS-defining events and mortality.A survival analysis was performed, using the Kaplan-Meier method and Cox proportional hazards models, for patients prospectively followed in the Swiss HIV Cohort Study, from January 1996 to December 2007, who were CMV-seropositive, had a CD4 count of ≤ 100 cells/μL, and had a plasma sample available for the measurement of baseline CMV DNA with an ultrasensitive PCR. The outcome analysed was an AIDS-defining event, including CMV end-organ disease, or death. Variables analysed at the time of CMV measurement were demographic variables, CD4 cell counts, HIV-1 RNA loads, and use and type of highly active antiretroviral therapy (HAART).Of 1128 patients, 208 (18%) presented an AIDS-defining event and 246 (22%) died. A total of 368 patients (34% of samples) had detectable CMV DNA at baseline, with DNA concentrations of up to 38 800 copies/mL. In the multivariate analysis, CMV DNA predicted evolution not only towards CMV end-organ disease [hazard ratio (HR) 12.6; 95% confidence interval (CI) 4.27-37.41], but also towards other AIDS-defining events (HR 2.6; 95% CI 1.60-4.33) and death (HR 1.9; 95% CI 1.10-3.34).Quantitative CMV DNA detected in the plasma of HIV-infected patients with CD4 counts ≤ 100 cells/μL is a predictor for HIV disease progression, CMV disease and death. A single low value of 80 copies/mL identifies patients at low but significantly increased risk during the following months, after the measurement.

International audience; In this paper we analyse some results on AIN CVD film deposition, published in the literature, from a morphological point of view, and we propose a model to explain the observed preferential orientations based on the reactivity of the AIN crystal faces of the equilibrium form.

Sic polycrystalline layers were grown by LPCVD in a hot wall reactor using tetramethylsilane (TMS) diluted in hydrogen as precursor. The morphology and the structure of the films were analyzed in terms of deposition temperature, total pressure in the reactor and TMS flow rate. The layers have been characterized using various techniques : SEM, X-ray diffraction and TEM (HREM and EELS).

Aluminium nitride has been obtained by chemical vapor deposition using AlCl3 and NH3 as precursors. Progressive introduction of N2O in the gas mixture has shown the possibility of inserting oxygen in the AlN lattice. This involves strong changes of surface morphology of the deposit and the formation of less-crystallized materials. When hydrogen is added to the gas mixture, these effects are reduced. Electron energy loss spectroscopy has shown that, in this case, oxygen is mainly concentrated on the external parts of AlN crystals, the structure of which has been found consistent with the wurtzite structure.

β-SiC layers were deposited on graphite substrates in a cold-wall LPCVD reactor using tetramethylsilane diluted in hydrogen as precursor. The dependence of morphology and textures on thickness and total pressure was studied. Structural and morphological analysis were performed using SEM. TEM and X-ray diffraction.

AIN crystalline thick films are obtained by LPCVD using trimethylaluminium and ammonia. A model is proposed to analyse the growth morphologies of these films. The equilibrium morphology of AIN, in a gas-solid system, is derived from the periodic bond chain analysis of the crystal structure and the application of the Bravais-Donnay-Harker law to the crystal lattice and space group. A morphological diagram, showing the habits produced by changing the relative rates of growth of the different crystal forms, has been constructed and used to describe the morphologies obtained in this work and a number of previous references. The influence of the reactant gas flows, the temperature, the total pressure and impurities (mainly hydrogen) on the morphology is analysed.

BSUMMARY BACKGROUND: Previous studies have shown an important risk of cardiovascular events in patients with clopidogrel biological non-response, and data have shown considerable, unexplored heterogeneity. OBJECTIVES: To evaluate the magnitude of cardiovascular risk associated with clopidogrel non-response and to explore heterogeneity. METHODS: This was a systematic review and meta-analysis of prospective studies of patients treated with clopidogrel for symptomatic atherothrombosis, evaluated by light transmission aggregometry with ADP and monitored prospectively for clinical ischemic events. RESULTS: Fifteen studies were included, totaling 3960 patients, of whom 25% were considered to be clopidogrel non-responders. The global relative risk (RR) for recurrent ischemic events in clopidogrel non-responders was 3.5 [95% confidence interval (CI) 2.4-5.2, P < 0.0001]. The results of the different studies were heterogeneous (Cochran P = 0.01 and I(2) = 52%). The most recent studies yielded lower RRs [global RR = 2.9 (95% CI 2.3-3.8) after 2007, and global RR = 6.6 (95% CI 3.7-11.9) before 2007, P = 0.01]. Heterogeneity was present in the group of studies in which more than 10% of patients took glycoprotein (GP)IIb-IIIa inhibitors [Cochran P = 0.003 and I(2) = 70%; RR = 3.8 (95% CI 2.9-5.1)] and was absent in the other studies [Cochran P = 0.88 and I(2) = 0; RR = 2.5 (95% CI 1.7-3.6)]. The RR was significantly higher in studies using higher ADP maximal aggregation cut-offs (> 65%) for clopidogrel non-response than in studies using lower cut-offs [RR = 5.8 (95% CI 3.2-10.3) and RR = 2.9 (95% CI 2.2-3.7), respectively, P = 0.03]. CONCLUSIONS: The risk of ischemic events associated with clopidogrel non-response is now more precisely defined. The risk is heterogeneous across studies, possibly because of an interaction with GPIIb-IIIa inhibitors and the use of different cut-offs to identify non-responders.

β-SiC polycrystalline layers were grown by LPCVD in a cold wall reactor using TMS (tetramethylsilane) diluted in hydrogen as precursur. The studies on the deposition show that the kinetics depends on temperature in the range between 1100 and 1500°C at a total pressure of 30 Torr. The morphology and deposition rate of the layers were related to four factors: temperature, TMS partial pressure, hydrogen partial pressure and gas velocity. The rate of deposition depends on the balance between heterogeneous and homogeneous nucleation, crystal growth, as well as the factors controlling crystal growth: adsorption processes, temperature, supersaturation and gas velocity.

β-SiC layers were obtained by low pressure chemical vapour deposition from tetramethylsilane diluted in H2 without contamination of free silicon and carbon at temperatures between 1100 and 1500 °C and at chamber pressures between 15 and 100 Torr. Changes in the deposition parameters have marked effects on the morphology, structure and microhardness of the layers.

Observational studies have indicated a high but heterogeneous prevalence of low bone mineral density for adult patients with cystic fibrosis. Fracture complications were also described. The objective of this study was to determine the prevalence of osteoporosis, osteopenia, and fractures among adult patients with cystic fibrosis. A systematic literature review was conducted using electronic databases. The keywords used were “cystic fibrosis [MeSH] AND bone density.” Original studies were eligible if they reported the prevalence of osteoporosis and/or osteopenia and/or fractures in adult patients with cystic fibrosis. A meta-analysis of pooled proportions was performed. Heterogeneity was tested with the Cochran Q statistic, and in the case of heterogeneity a random effect model was used. Of 117 studies, 12 were selected, i.e., that represented a total of 1055 patients. Mean age ranged from 18.5 to 32 years (median: 28.2 years). Mean body mass index ranged from 19.9 to 22.4 (median: 20.7); 53.8% were men. The pooled prevalence of osteoporosis in adults with cystic fibrosis was 23.5% (95% CI, 16.6–31.0). The pooled prevalence of osteopenia was 38% (95% CI, 28.2–48.3). The pooled prevalences of radiological vertebral fractures and nonvertebral fractures were 14% (95% CI, 7.8–21.7) and 19.7% (95% CI, 6.0–38.8), respectively. In conclusion, this systematic literature review with meta-analysis emphasized the high prevalence of osteopenia and osteoporosis in young adults with cystic fibrosis. The prevalence of fracture was also high.

In general, blood gas analysers can also determine the value of haematocrite by measuring the blood's conductivity. The question to ask is whether this value is reliable. In this study, hematocrit obtained via conductivity from 6 different pieces of equipment were compared with those measured using the gold standard method, which is microcentrifugation. By interpreting the results of 320 arterial blood samples taken in the intensive care unit DAR "B" we can see that the reliability between two measurements on the same piece of equipment is very good, in general0.95 whatever the equipment. The reliability between the means of the two measurements and the gold standard is slightly lower but remains very satisfactory, most often between 0.8 and 0.9. The Gem Premier 3000 (IL) analyser and the Roche OMNI S gave the best reliability compared with centrifugation. The Spearman coefficients between the mean values of the analysers and those of centrifugation were high, with the exception of the Rapidpoint 405. They are all statistically different from zero (p0.0001).

SiC polycrystalline layers were grown by LPCVD in a cold wall reactor using TMS (tetramethylsilane) diluted in hydrogen as precursor. TMS has the advantage of supplying Si and C from an individual molecule free from halogen. The dependence of the kinetics of deposition on substrate temperature, total pressure and TMS partial pressure was obtained. Structural and morphological analysis were performed using SEM and X-Ray diffraction.

Using chemical vapour deposition, aluminium-oxygen-nitrogen system coatings have been synthesized with trimethylaluminium, ammonia and nitrous oxide. The composition of the equilibrium phases is first determined by a thermodynamic calculation. The only Al-O-N phase investigated is (γ) spinel aluminium oxynitride and it is considered as a stoichiometric phase with the Al 7 O 9 N composition. The results indicate the existence fields of aluminium nitride and alumina, and show the difficulty of obtaining the spinel aluminium oxynitride without other phases. Temperature and pressure influence the equilibrium compositions because they directly modify the quantity of CO present. A cold-wall reactor is used for the experimental study. In this way AlN, a mixture of AlN and γ-AlON (γ-aluminium oxynitride), and α-Al 2 O 3 are obtained. The annealed deposits show the stability of γ-AlON obtained at 1370 K.

The allergic rhinitis and its impact on asthma (ARIA) guidelines provide a new classification of allergic rhinitis, but a quantitative analysis for severity assessment is lacking.To study whether a visual analog scale (VAS) for global rhinitis symptoms could be used to assess the disease severity according to ARIA.Three thousand fifty-two allergic rhinitis patients seen in primary care were tested. Fifty three per cent had an objective diagnosis of allergy and 58% of the patients were treated. Patients were categorized according to ARIA guidelines. The severity of nasal symptoms was assessed using a VAS. Quality of life was measured using the rhinoconjunctivitis quality of life questionnaire (RQLQ).Severity had more impact on VAS levels than duration: mild intermittent rhinitis (3.5, 2.4-5.0 cm), mild persistent rhinitis (4.5, 3.2-5.6 cm), moderate/severe intermittent rhinitis (6.7, 5.3-7.7 cm) and moderate/severe persistent rhinitis (7.2, 6.1-8.2 cm). The receiver operating characteristic curve results showed that patients with a VAS of under 5 cm could be classified as 'mild' rhinitis (negative predictive value: 93.5%) and those with a VAS of over 6 cm as 'moderate/severe' rhinitis (positive predictive value: 73.6%). Receiver operating characteristic curves and a logistic regression showed that current treatment and allergy diagnosis have no effect on the assessment of rhinitis severity using VAS. Visual analog scale and the RQLQ global score were significantly correlated (rho = 0.46; P0.0001).A simple and quantitative method (VAS) can be used for the quantitative evaluation of severity of allergic rhinitis.

An evaluation process directed by the biochemistry department of the UHC of Montpellier about acquisition of blood gas analysers for a point of care testing in 10 different medical care services. The values obtained by the different measurement machines have been compared taking into account the intra and inter measures variabilities. In this work, the results of 4 machines tested: Rapid-point 405, GEM Premier 3000, i-STAT 1 (série 300) and ABL 77 are compared with one i-STAT (série 200) and one OMNI S already available in the laboratory. The study lasted one month (november 2004). Each week, the two machines of the laboratory was compared with a new analyser randomly chosen between the four machines tested. In this study, including 21000 values, the statistical tests have been applied under the hypothesis that none of the measurement machine could be a "gold standard". Beside the classical research of correlation between the different values, we added the research of concordance between machines and the application of imperfect gold standard method. A high level of statistic concordance was observed between the different analysers. So the equipment has been selected using biological, analytic and computing criteria.

5 pages, 6 figures, 2 tables., This paper reports the results obtained by the development of a new wet method of hydroxyapatite (HA) thin layer deposition. The method is based on the localized precipitation of HA on metallic substrates activated by induction heating. The technique developed has been shown to allow for the complete coating of substrates with micrometric thin films of HA within a low processing time. The method has been successfully applied to coat Ti plaques and Ti-6Al-4V cylinders., This work has been carried out in the framework of the Spanish-French LEA-SIMAP Laboratory. The Ministry of Science and Technology of Spain is acknowledged with thanks for financial support of D.N.M. within the program “Ramon y Cajal”.

In studies of disease states and their relation to evolution, data on the state are usually obtained at in frequent time points during follow-up. Moreover in many applications, there are measured covariates on each individual under study and interest centres on the relationship between these covariates and the disease evolution. We developed a continuous-time Markov model with use of time-dependent covariates and a Markov model with piecewise constant intensities to model asthma evolution. Methods to estimate the effect of covariates on transition intensities, to test the assumption of time homogeneity and to assess goodness-of-fit are proposed. We apply these methods to asthma control. We consider a three-state model and we discuss in detail the analysis of asthma control evolution.

Control and severity of asthma are two different but complementary concepts. The severity of asthma could influence the control over time. The aim of this study was to demonstrate this relationship. A total 365 patients with persistent asthma (severity) were enrolled and followed-up prospectively. Data were analysed using a continuous time homogeneous Markov model of the natural history of asthma. Control of asthma was defined according to three health states which were qualified: optimal, suboptimal and unacceptable control (states 1, 2 and 3). Transition forces (denoted λij from state i to state j) and transition probabilities between control states were assessed and the results stratified by asthma severity were compared. Models were validated by comparing expected and observed numbers of patients in the different states. Transition probabilities stabilised between 100–250 days and more rapidly in patients with mild-to-moderate asthma. Patients with mild-to-moderate asthma in suboptimal or unacceptable control had a high probability of transition directly to optimal control. Patients with severe asthma had a tendency to remain in unacceptable control. A Markov model is a useful tool to model the control of asthma over time. Severity modified clearly the health states. It could be used to compare the performance of different approaches to asthma management. This study was supported by an unrestricted educational grant from GlaxoSmithKline, France.

Alcoholism is a worldwide problem. Many strategies for alcohol detoxification and relapse prevention exist, but each alcohol treatment center has its own program. The objective of this study was to analyze and compare the financial cost and effectiveness of alcohol treatment programs from inpatient stay to follow-up 1 year later. This was a prospective, open, nonrandomized study of 4 specialized alcohol treatment centers and 267 patients admitted for alcohol detoxification.We recorded all medical and nonmedical interventions related to the program during patient stay in the hospital and every 3 months after discharge for 1 year and recorded the occurrence of alcohol relapse. Financial evaluation was based on the prices of refund from the French national health insurance service.The mean cost of hospitalization ranged from 1326 euros to 1917 euros(p = 0.001), a variation mainly due to the difference in the length of hospital stay but also to the cost of the inpatient program, routine medical checkups, and drugs administered. The mean cost of 1 year of follow-up per patient ranged from 419 euros to 1704 euros (p = 0.001). The efficiency, corresponding to the money spent to prevent the relapse of one patient during 1 month, was approximately 500 euros/month in three centers and 658 euros in the fourth. However, for a similar efficiency, the effectiveness, assessed by the mean time without relapse, was significantly (p = 0.001) different; center 1, which had the highest total cost, had an effectiveness 1.56 times higher than center 3, which had the lowest cost.This work emphasizes the heterogeneity of the costs and effectiveness of alcoholism treatment programs and suggests that research should be conducted to determine which program is the most rational, cost-efficient, and beneficial for patients and the public health office economy.

La colistine et les imipeneme gardent leur efficacite avec un taux de resistance inferieur a 10%. Les germes presentant une betalactamase a spectre Elargi (BLSE) representent la grande majorite, temoin des prescriptions abusifs, et des conditions de sondage et de soins de sonde. Conclusion.— Il devient necessaire de revoir les protocoles de sondage, de prendre en compte l’epidemiologie locale des resistances bacterienne lors de la prescription des antibiotiques, et de rationaliser cette prescription afin de diminuer le risque de developpement des resistances.

A hot wall CVD reactor has been especially adapted to the problem of producing codeposits of aluminium and silicon nitrides. The experimental set-up for preparing "in situ" aluminium trichloride or a mixture of AlCl3 and SiCl4 by the action of silicon tetrachloride on an aluminium supply, heated to temperatures (Tc) between 380 and 520 °C is presented. A study was also made of the deposition kinetics using a thermobalance with a continuous recording facility. The deposition kinetics of AIN and Si3N4 were measured and compared. The codeposits prepared at a temperature of 1200 °C and a total pressure of 1 Torr were found to be adherent when deposited on a graphite substrate covered by a layer of silicon carbide obtained by pyrolysis of tetramethylsilane at 1240 °C. The deposits were characterized by a variety of methods : X-ray diffraction, wavelength dispersive spectroscopy and scanning electron microscopy.

The deposition rate and uniformity in CVD reactors are function of transport phenomena. A mathematical model including the coupled mass transfer with hydrodynamics and heat transfer has been developed to predict reactant concentrations, flow patterns and temperature fields in a cold wall CVD reactor. The model consists of the partial differential equations describing the balance of mass, momentum, heat and species concentration and variable gas properties. The equations are solved numerically in two-dimensional, axisymmetric form using a control-volume-based finite difference technique. The model is applied to growth of silicon carbide layers obtained by LPCVD from the pyrolysis of tetramethylsilane. We present computed temperature, velocity and TMS concentration profiles. We compare predicted deposition rates with experimental results

We have studied the codeposition of aluminum nitride and silicon nitride, using aluminum trichloride and silicon tetrachloride as vectors of aluminum and silicon respectively, ammonia as source of nitrogen, and nitrogen as carrier gas. A preliminary thermodynamic study allowed us to determine the influence of pressure, temperature and gas composition on the Al, Si, N, H, Cl system. Particularly, we have shown that the Al/Si ratio as well as the quantity of ammonia play a crucial role in the composition of the codeposit. An experimental study has been carried out using a hot-wall reactor. At 1253 K with a pressure of 133 Pa, we have obtained deposits varying from AIN to Si 3 N 4 , via intermediate compositions, by varying the reactive gas mixture. The codeposits have been characterized using various methods such as X-ray diffraction, Auger, X.P.S., S.E.M. and E.P.M.A

We have studied the chemical vapour deposition of alumina (Al 2 O 3 ) using aluminium chloride (AlCl 3 ) as a source of aluminium and nitrous oxide (N 2 O) or carbon dioxide (CO 2 ) as the oxygen vector. We also used hydrogen (H 2 ) and a carrier gas (N 2 ). A preliminary thermodynamic study indicated the influence of temperature, total pressure of the reactants and the composition of the gas mixture. The synthesis of the alumina deposited was carried out in a hot-wall reactor at temperatures between 1000 and 1300 o C and at pressures varying from 133 to 665 Pa. All deposits were crystallised and adherent to the substrates of silicon carbide (SiC) or aluminium nitride (AlN). The structure and crystallographic orientation of the Al 2 O 3 films were investigated by X-ray diffraction. Particular attention was paid to the morphology of the deposits. Observations were made with the help of a Scanning Electron Microscope (SEM). Two studies were carried out as a function of temperature, one for the deposits made from nitrous oxide and the other for those made using carbon dioxide. The crystal size of Al 2 O 3 increases with temperature but, more importantly, the crystal habit changes too

Using chemical vapour deposition, aluminium - oxygen-nitrogen coatings have been synthesized with aluminium trichloride, hydrogen, ammonia and nitrous oxide. The composition of the equilibrium phases is first determined by a thermodynamic calculation. The only AlON phase we investigate is ([MATH]) spinel aluminium oxynitride and it is considered as a stoichiometric phase with a composition of Al7O9N. The results indicate the existence fields of aluminium nitride and alumina and show the difficulty of obtaining the spinel aluminium oxynitride without other phases. Temperature, pressure and gas composition play an important part because they directly influence the reactivity of aluminium chloride. A hot-wall reactor is used for the experimental study. In this way, we obtain AlN, a mixture of AlN and [MATH] AlON, and [MATH] Al2O3. The annealed deposits show the stability of AlON obtained at 1270K.

Silicon carbide layers have been produced by Chemical Vapor Deposition at low pressures (LPCVD) on graphite substrates from tetramethylsilane and hydrogen. The effects of change in partial pressure of hydrogen on the kinetics, morphology and structure of the layers have been examined. A model of the layer growth is developed.

A mathematical model including the NAVIER-STOKES and energy partial differential equations has been developed to predict the flow and temperature fields in a cold-wall CVD reactor. Particular attention is placed on understanding and explaining the influence of pressure on the hydrodynamics and heat transfer in the reactor. In order to validate the model predictions in the thermal aspect we used holographic interferometry to investigate the temperature gradients and to examine the thermal boundary layer thickness for several reactor inlet conditions. The comparison between the model predictions and experimental data shows good agreement.