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A question that the Stroke Prevention in Atrial Fibrillation Investigators 1 could answer with their data is whether the elderly patients taking warfarin sodium who suffered intracranial hemorrhage had a mean body mass index that was significantly lower than the elderly patients taking warfarin who did not bleed. The association between an age older than 75 years and the risk for a major hemorrhage while taking warfarin was confirmed of course in the secondary prevention trial. 2 It is not clear from the article whether body mass index was one of the baseline characteristics tested against warfarin-related major hemorrhage and, if it was or was not, this should be stated since it is clearly of interest. Undernutrition is very common in elderly, hospitalized patients, and as total energy intake decreases, there is usually a failure to compensate by increased nutrient density, in particular with vitamin K—containing plants. This area has

Penetration into the middle ear of four antibiotics commonly used in treatment of otitis media was studied by administering a single oral dose of amoxicillin, cefaclor, erythromycin-sulfisoxazole, or trimethoprim-sulfamethoxazole to 83 children with chronic serous otitis media. The antibiotic was given 15-240 min before the removal of middle ear fluid (MEF) by ventilation tubes inserted through the tympanic membrane. At the time MEF was obtained, a sample of blood was drawn from the patient, and concentrations of antibiotic in both specimens were assayed either microbiologically by a disk diffusion method or by high-pressure liquid chromatography. Amoxicillin had the highest ratio of mean peak concentration in MEF to minimal inhibitory concentration (MIC) for the three most common pathogens of otitis media (Streptococcus pneumoniae, ampicillin-sensitive Haemophilus influenzae, and Streptococcus pyogenes), whereas trimethoprim-sulfamethoxazole had the highest ratio of mean peak concentration in MEF to MIC for ampicillin-resistant Haemophilus influenzae.

Irregularities in vital sign (pulse, blood pressure, cardiac rhythm) recordings are commonly observed following acute spinal cord injury. These abnormalities have been generally attributed to autonomic instability. However, there have been no clinical reports that evaluate these problems in a large group of acutely injured patients. Therefore, this study was performed on 45 patients with acute cervical spinal cord injuries to evaluate the incidence, severity, and risk factors for cardiovascular instability. This investigation revealed that there is a direct correlation between the severity of the cord injury and the incidence and severity of cardiovascular problems. Endotracheal suctioning with or without documented hypoxia are major causes of severe bradycardia and cardiac arrest within the first 2 weeks after trauma. Careful monitoring of severely injured patients and attention to the warning signs of cardiovascular instability can reduce the risk of life-threatening emergencies. Key Words: Bra...

H2 + and H3 + ions, produced in a H2 plasma of a radio-frequency ion source, were accelerated to 6-60 keV and directed into a gas target of Krypton. The cross sections for the formation of H+ and H- resp. H2 +, H+ and H- have been measured. In the case of H+, obtained from the dissociation of H2 +, 2 maxima have been found in the present energy range. A third is known to be at about 100 keV. We discuss the applicability of the Massey' adiabatic hypothesis, known from the analysis of charge-exchange experiments, to the maxima in the cross-section vs. energy curve for dissociation experiments.

A plane mirror mounted on an optical scanner was used to deflect the outgoing beams of a laser‐Doppler anemometer operated in backscatter mode, thus permitting, through movement of the mirror, rapid scanning of the measuring control volume throughout the flowfield. Furthermore, the use of a zoom lens element in the transmitting optics enabled the depth range of measurement to be extended without the need to mechanically traverse the system. The signal analysis for a scanning LDA is considered for the case of mean and fluctuating velocity measurements and the effects of the inherent spatial averaging is examined. The analysis yields results that are confirmed by measurements made in a simple coaxial air jet using a transient recorder‐based signal processing system. Several improvements to the present system are suggested and the applicability of the scanning LDA in turbulence research is discussed.

The aim of the present study was to investigate stereologically the histologic alterations occurring during gingival healing after experimental gingivitis and to compare clinical parameters with histological findings. 8 dental students volunteered for the investigation. After a prophylaxis, they performed optimal oral hygiene to reach mean plaque and gingival indices approaching zero. They then abolished all oral hygiene procedures for a period of 21 days. After this experimental gingivitis phase, they again performed optimal oral hygiene for 8 days to restore gingival health. At days 0. 1, 2, 4, and 8 after experimental gingivitis, the plaque index (PII), the gingival index (GI) and the gingival exudate flow rate (GEFR) were assessed and their buccal gingiva was biopsied. Point counting procedures were performed at 2 different levels of magnification on light microscopic sections to estimate the volume fractions of epithelium, infiltrated and non-infiltrated connective tissue, and collagen. The relative numbers of fibroblasts, polymorphonuclear neutrophils. lymphocytes, plasma cells and macrophages were estimated by counting the number of profiles of these cells in a specific connective tissue area adjacent to the apical end of the junctional epithelium. A rapid drop in the PII was noted with increasing time after oral hygiene, followed by a slower decrease in the GI and GEFR scores. The histological picture during the entire experiment was that of an initial gingival lesion. At day 0, no chronic inflammation of the gingiva characterized by a predominance of plasma cells was observed. After resumption of oral hygiene when the relative cell numbers at day 0 and day 8 were compared, only an increase in the PMN population was observed. As GI and GEFR scores decreased no significant changes were noted in the relative numbers of the various cell types. These observations suggest that the “physiogenesis during experimental health” appears first clinically and then histologically, and hence, it may take more than 8 days to observe significant variations in cell populations.

The feasibility of IR laser spectroscopy as a technique for the measurement of small abundances of stable and radioactive isotopes has been examined. Theoretical considerations and first experimental results with two laser systems are presented: 1) Coincidences between emission lines of a CO2-laser and absorption lines of13C-substituted ethylene can be used to determine the13C-concentration of C2H4. 2) A tunable PbS-diode laser emitting in the 4.3 μm-spectral region of the rotation-vibration bands of CO2 can be used to determine abundances of12C,13C,16O,17O and18O in small samples of CO2. With optimized performance, sensitivities up to 10−9–10−10 seem possible, and for higher abundances an accuracy of 10−3. This should allow geophysical isotope studies to be performed and it is hoped that the technique will eventually be applicable to measuring the activity of long-lived radioisotopes.

Paraoxon and methyl-parathion (Wofatox), frequently used organophosphate pesticides, were tested for cytogenetic effects in lymphocytes of persons with different phenotypes of paraoxonase activity. Sister chromatid exchanges (SCE), chromosome breaks, and cell cycle traverse were studied in ten individuals. Paraoxon showed no significant effects whereas methyl-parathion showed a dose-dependent increase in the SCE and a definite delay in the cell cycle as assessed by fluorescence plus Giemsa technique. No significant clastogenic effects and no difference in response were observed among individuals with different phenotypes of paraoxonase.

The γ-ray angular correlation of the 9/2+, 37 μs state in81Br and of the 181 keV, 120 μs state in78Br was disturbed by nuclear magnetic resonance. Theg-factors were determined to be ¦g¦=1.297±0.015 for the 37 μs level in81Br and ¦g¦=1.025±0.003 for the 120 μs state in78Br.

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Motivated by the possibility to use high intensity neutrino beams for neutrino-nucleon scattering experiments we analyze charged current induced exclusive meson production within the framework of generalized parton distributions. The cross section for hard exclusive D_s production is estimated in this formalism to leading order in QCD. The integrated cross section proves to be sizable. It is shown that the considered process is well suited to provide novel information on the gluon structure of nucleons, which is contained in the generalized gluon parton distribution., 7 pages; modified plots in Fig. 3; accepted for publication in Phys. Lett. B

An extremely rare laryngeal hamartoma causing inspiratory stridor in a 6-week-old infant is reported and the histology discussed. The tumor is benign and responds to simple excision. No other cases have been found in the 20th century American literature.

The problem of MR simulation of biologic tissues has been approached by many authors (5, 10) with different purposes, such as a better understanding of both relaxation mechanisms (2, 3) and RF power dissipation in tissues (6, 7). The aim of this investigation was to find a phantom material which could be used for easy control of some performances of an MR imaging system. In general, the goal was to check the quality of TI and T2 computed images and to compare signal intensity of the proposed medium with that of the tissue of interest, in scans routinely performed with standard pulse sequences. As previously proposed (1, lo), an agar gel was chosen, because of its T2 relaxation properties. In fact, owing to the semisolid behaviour when agar is dissolved in water (9). the structure of the gel presents a restricted motion of bound and free water. Moreover, if paramagnetic ions are added to an agar solution, TI and T2 values are even more strongly reduced than in an aqueous solution, so that, by combining different weight percentages of agar and paramagnetic ion concentrations, the main range of living tissues can be covered. In fact, whereas spin-lattice and spin-spin relaxation rates (1/T1 and 1R2, respectively) of an aqueous solution of transition metals have the same dependence on ion concentration, they are differently affected by the percentage of agar present (4, 5, 10). TI and T2 can therefore be varied independently, so that TI can be greater or much greater than T2 as in some natural biologic tissues.

Cross sections have been measured for some charge changing processes occuring when single-positive atomic ions, with 12 - 60 keV, collide with Kr atoms. The ions are H+, C+, N+, O+ and S+. The apparatus only permitting registration of charged collision products, the observed processes are electron loss and double electron capture by the primary ions.

Principles of and experiments with a special optical laser Doppler arrangement are described. This arrangement allows measurements to be made of the velocity component that is directed onto the main optical head. The method requires a few additional simple elements positioned opposite the optical head of a multiple-beam arrangement, which serve to reflect one of the two laser beams coaxially back to the probe volume. The unavoidable difference in optical path length between the reflected and the original beam, when intersecting within the probe volume, is not necessarily a problem even when using high-power lasers. Sufficient modulation depth is recovered if the path length difference is made twice the resonator length. Using this method, three orthogonal-component LDA measurements can be carried out, based on three combined dual-beam systems.

9. Shurin PA, Pelton SI, Scheifele D, and Klein JO: Otitis media caused by non-typable, ampicillin-resistant strains of Haemophilus influenzae, J PED~ATR 88:646, 1976. 10. Yogev R, Lander HB, and Davis AT: Effect of TMP-SMX on nasopharyngeal carriage of ampicillin-sensitive and ampicillin-resistant Haemophilus influenzae type B, J PEmATR 93:394, 1978. 11. Kirven LA, and Thornsberry C: Minimum bactericidal concentration of sulfamethoxazole-trimethoprim for Haemophilus influenzae: Correlation with prophylaxis, Antimicrob Agents Chemother 14:731, 1978. 12. May JR, and Davies J: Resistance of Haemophilus influenzae to trimethoprim, Br Med J 3:376, 1972. 13. Trickett PC, Dineen P, and Mogabgab W: Trimethoprimsulfamethoxazole versus penicillin G in the treatment of group a beta-hemolytic streptococcal pharyngitis and tonsillitis, J Infect Dis 128:$693, 1973. 14. Bateson MC, Hayes JPLA, and Pendharker P: Cotrimoxazole and folate metabolism, Lancet 2:339, 1976. 15. Hitchings GH: Mechanism of action of trimethoprimsulfamethoxazole--I, J Infect Dis 128:433, 1973. 16. Burchall JJ: Mechanism of action of trimethoprim-sulfamethoxazole-lI, J Infect Dis 128:$437, 1973. 17. Hjortsh~j A, Elsborg L, and Jensen E: Folate status during long-term therapy with trimethoprim and sulphadiazine, Chemotherapy 24:327, 1978. 18. Hughes WT, Kuhn S. Chaudhary S, Feldman S, Verzosa M, Aur RJA, Pratt C, and George SL: Successful chemoprophylaxis for Pneumocystis carinii pneumonitis, N Engl J Med 297:1419, 1977. 19. Herbert V: Biochemical and hematologic lesions in folic acid deficiency, Am J Clin Nutr 20:562, 1967. 20. Chan TK, and McFadzean AJS: Haemolytic effect of trimethoprim: Sulphamethoxazole in G-6-PD deficiency, Trans R Soc Trop Med Hyg 68:61, 1974. 21. Shurin PA, Pelton SI, Donner A, and Klein JO: Persistence of middle-ear effusion after acute otitis media in children, N Engl J Med 300:1121, 1979.

The spin precession about the rf field vector H1 (t) was observed time-differentially by means of the γ-angular correlation of the 120 μs state in 78Br.

The γ-ray distribution of the 11− 2 159 μs state in 115Sn was distributed by nuclear magnetic resonance yielding a magnetic moment ∣μ∣ = 1.361 ± 0.004 nm. The relaxation time for the excited 115Sn nuclei in liquid indium metal is τR = 0.75 ± 0.18 ms.