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Ajmaline, a rauwolfia derivative, has been found to possess potent antiarrhythmic effects. The present study has been designed to define the cardiovascular effects of this drug. Hemodynamic studies performed in anesthetized and conscious dogs demonstrated no significant changes in measured hemodynamic parameters at doses equal to or less than 2 mg. per kilogram. Studies in isolated papillary muscle demonstrated no negative inotropic effects until concentrations of 1 X 10(-4). Disparate results were obtained with regard to heart rate reflecting the state of autonomic tone. Electrophysiologic studies in both anesthetized and conscious dogs demonstrated a significant depression of intraventricular conduction with no significant effect on AV nodal conduction; ventricular automaticity was not affected. Ajmaline did not alter digitalis-induced AV nodal conduction prolongation. However, ajmaline dramatically altered or abolished ventricular arrhythmias secondary to acute ischemia. In conclusion, these studies demonstrate that ajmaline specifically depresses intraventricular conduction, suggesting that this drug would be particularly effective in the treatment of re-entrant ventricular arrhythmias.  相似文献   
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The testosterone concentration in allantoic fluid between 90 and 150 days of gestation in cattle can be used to determine the fetal sex; values were 442 +/- 20-3 (S.E.M.) pg testosterone/ml for males fetuses and 215 +/- 8-2 pg/ml for female fetuses.  相似文献   
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Eight out of 115 infants admitted to hospital with respiratory syncytial (RS) virus infection had been breast-fed compared with 46 out of 167 controls; this difference was statistically significant. Twenty-one specimens of human colostrum were examined, and all contained RS virus neutralising activity. Specific IgA and IgG were detected in 18 specimens, whereas IgM was detected in none. The titre of IgA antibody was usually higher and correlated more closely to the titre of neutralising activity than that of IgG. Infants inhale milk feeds and regurgitate them through the nose, and the IgA collecting in the respiratory tract might protect against severe respiratory infection. Alternatively, if severe RS virus illness is a sign of hypersensitivity to the virus breast-feeding might protect the infant from an early sensitising infection.  相似文献   
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A galactosidase immunosorbent test for human immunoglobulin E   总被引:1,自引:0,他引:1  
We report here the development of a galactosidase-immunosorbent test (GIST) for immunoglobulin E (IgE) antibodies in which the amount of galactosidase adsorbed to a cellulose disc is a single valued function of IgE concentration in human serum. Rabbit anti-IgE immunoglobulin insolubilized on cellulose discs is incubated sequentially with human serum, sheep anti-IgE serum, and a covalent conjugate of rabbit antisheep immunoglobulin with the enzyme beta-D-galactoside galactohydrolase (E.C.) 3.2.1.23). Colorimetric assay of enzyme conjugate adsorbed to discs permits quantitation of 1.0 to 25 ng of IgE per test. Concentrations of IgE in 48 sera as measured by the GIST gave a linear correlation coefficient of 0.97 with IgE concentrations as determined by radioimmunoassay. Preliminary studies indicate that the GIST makes possible nonisotopic measurement of ragweed-specific IgE antibiotics in human serum. The GIST for IgE is simple to perform and requires neither short-lived radioisotopes, expensive scintillation detection equipment, nor scarce, purified IgE.  相似文献   
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Background

Epidemiological studies have reported associations between reduced cardiovascular disease and diets rich in tomato and/or lycopene. Intervention studies have shown that lycopene-containing foods may reduce cholesterol levels and lipid peroxidation, factors implicated in the initiation of cardiovascular disease. The objective of this study was to determine whether consumption of lycopene rich foods conferred cardiovascular protection to middle-aged adults as indicated by plasma lipid concentrations and measures of ex vivo antioxidants.

Methods

Ten healthy men and women consumed a low lycopene diet with no added lycopene (control treatment) or supplemented with watermelon or tomato juice each containing 20 mg lycopene. Subjects consumed each treatment for three weeks in a crossover design. Plasma, collected weekly was analyzed for total cholesterol, high density lipoprotein cholesterol (HDL-C) and triglyceride concentrations and for the antioxidant biomarkers of malondialdehyde formation products (MDA), plasma glutathione peroxidase (GPX) and ferric reducing ability of plasma (FRAP). Data were analyzed using Proc Mixed Procedure and associations between antioxidant and lipid measures were identified by Pearson's product moment correlation analysis.

Results

Compared to the control diet, the lycopene-containing foods did not affect plasma lipid concentrations or antioxidant biomarkers. Women had higher total cholesterol, HDL-C and triglyceride concentrations than did the men. Total cholesterol was positively correlated to MDA and FRAP while HDL-C was positively correlated to MDA and GPX. GPX was negatively correlated to triglyceride concentration.

Conclusions

The inclusion of watermelon or tomato juice containing 20 mg lycopene did not affect plasma lipid concentrations or antioxidant status of healthy subjects. However, plasma cholesterol levels impacted the results of MDA and FRAP antioxidant tests.  相似文献   
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A clinical study of hand strength and complications in 41 patients with a transmetacarpal amputation of the index finger found that the average prehension strength was reduced by 20% and stability of grip by almost 50%. Tendon transfers or other operative modifications did not affect the results. The most disabling complication, hyperesthesia, or painful sensitivity to light touch, in the thumb--long-finger web was present in 59% of patients and interfered with hand function in 37%.  相似文献   
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