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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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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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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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The level of PGE is increased 10-fold in intestinal tissues during primary infection of the rat with Nippostrongylus brasiliensis. Peak levels (ca. 7,000 pg/cm) were assayed in the jejunal site of infection on day 7 of infection and similar levels were recorded in 'post-infection' (ileal) segments at this time. The level of PGE in 'post-infection' segments showed further increase to 12,000 pg/cm on day 10. The level of PGE also increased in 'pre-infection' (duodenal) but this was delayed by 4-5 days. The level of PGF also increased during primary infection (from about 100 to 950 pg/cm) but this occurred after expulsion. Increase in the level of PGE occurred earlier (at 3-4 days) during secondary challenge given 19 days after primary infection, but the PGE levels followed the primary response when challenge was given 10 weeks after primary infection. It is suggested that PGE plays a dual role in parasite immunity. (1) PGE may directly affect metabolism of the parasite. In this event it is also suggested that protective antibodies cause the release of PG. (2) Elevated levels of PGE act indirectly by affecting gastrointestinal function which alters the microenvironment at the site of infection. The duodenal migration of parasites may be due to this effect of PGE.  相似文献   
18.
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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The director, one other professional, and one para-professional in 515 community mental health centers and 193 state hospitals throughout the United States were asked to rate 57 critical issues in mental health services as to their importance now and five years from now. Issues judged most important now are services for children and for adolescents; five years from now children's services still top the list. Answers to two other questions revealed that respondents placed research on prevention at the top of a list of needed research areas, and that the most useful NIMH service to agencies was person-to-person assistance such as consultation and workshops.  相似文献   
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