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31.
A competitive type-specific enzyme-linked immunosorbent assay (ELISA) for herpes simplex virus type 2 (HSV-2) antibody was developed using an infected cell antigen and a monoclonal antibody to glycoprotein G-2. This assay has been validated for use for epidemiological studies using a large panel of sera collected in rural Uganda and a panel of 143 sera characterised previously by Western blotting, the 'gold standard' for HSV type-specific serology. This evaluation was found to have a sensitivity of 96% and a specificity of 91% in comparison with Western blot on 143 sera from clinic patients. The ELISA had a sensitivity of 93% and a specificity of 91% in comparison with Western blot on 495 sera collected in Uganda. The assay showed good reproducibility and a low percentage of sera gave equivocal results, indicating its suitability for epidemiological studies.  相似文献   
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Acute energetic effects of daunomycin on rabbit heart muscle   总被引:1,自引:0,他引:1  
The acute effects of daunomycin on the mechanical and energetic outputs of rabbit papillary muscles have been examined at 27 degrees C using a myothermic technique. Contrary to expectations, daunomycin, in concentrations ranging from 10 to 160 micrograms/ml, acted as a positive inotropic agent in terms of peak stress development and work output. The rate of stress development was, however, slightly depressed, and the major mechanical effect of the drug was to prolong the relaxation phase so that there were large drug-dependent increments in the stress-time integral. Daunomycin at a concentration of 80 micrograms/ml produced a 22% increment in peak stress development and a 74% increment in stress-time integral. The linear relationship between total (active + passive) stress and heat production was altered such that there was a 73% increment in the activation heat component (intercept) and a 37% increase in the energy cost per unit stress development (slope). In afterloaded isotonic contractions, daunomycin increased the mean work output (W; averaged over all load levels) by 49%, but there was an even greater increment in the associated energy expenditure, ET, which rose by 66%. Consequently, the overall mechanical efficiency (W/ET X 100%) fell slightly. It is concluded that, in the rabbit, daunomycin in the acute situation increases total calcium delivery to the myofilaments and decreases the "apparent" transduction efficiency. These acute effects are the opposite of those reported in papillary muscles taken from rabbits in cardiac failure induced by chronic daunomycin administration. The short-term effects of daunomycin in the rabbit differ substantially from those seen in the rat and guinea pig.  相似文献   
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A positive correlation has been observed clinically at the Centre Edouard Rist, Paris, between the degree of pigmentation and the power of isoniazid acetylation in so-called "caucasians". The investigation was based on a relatively small sample of 153 observations, but sufficient to allow a significant statistical analysis. Comparing the results with data published in the literature, it may be assumed that this relationship between the power of acetylation and pigmentation would be applicable to all human beings. The rabbit, having as in man a bi-modal distribution of the power of acetylation, was used for further research of this correlation in that animal. The results of this research in rabbits may be compared with those in man, but further studies are required in view of the interest of this comparison and of the possible consequences of the relationship of pigmentation and the degree of acetylation of isoniazid in human therapeutics.  相似文献   
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Objective: In a randomized trial, we sought to determine whether 2% clindamycin cream administered intravaginally during labor to group B streptococcal-colonized pregnant women without risk factors would decrease maternal and neonatal colonization.Methods: The eligible women were randomized to receive either cream or no treatment. Two hours after treatment or admission, the patients were tested with rectal and vaginal cultures. The neonates of the study patients were also tested.Results: Of women randomized to cream, 5 of 5 remained positive and 2 (33%) of their 6 neonates were positive. Of 4 randomized to no treatment, 3 (75%) remained positive and 1 (25%) of 4 neonates was positive.Conclusions: Intravaginal 2% clindamycin cream was ineffective in reducing colonization with group B streptococci.  相似文献   
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Pheochromocytoma is an uncommon tumor in childhood. The simultaneous occurrence of adrenal and cervical pheochromocytomas is a rare phenomenon; to our knowledge, this combination has been reported in the literature only once. Cervical pheochromocytomas are more accurately termed "aorticosympathetic paragangliomas." In children, 50% of pheochromocytomas are bilateral, multiple, or extra-adrenal. An increased familial incidence in the form of simple mendelian dominance is also noted in the pediatric age group. Bolus nephrotomography is extremely effective in identifying adrenal pheochromocytomas in children. To prepare the patient for surgery, and alpha-adrenergic blocking agent is administered from 7 to 10 days before operation and a beta-blocking agent is administered 3 days before. A transabdominal approach is essential because of the frequent extra-adrenal sites and multicentricity of the tumor in children.  相似文献   
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