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Testicular function after orchiopexy for unilaterally undescended testis.   总被引:4,自引:0,他引:4  
Testicular function was determined in 29 men, 21 to 35 years old, who had undergone orchiopexy for unilaterally undescended testis at four to 12 years of age. Serum testosterone and dialyzable testosterone concentrations of these men were not significantly different from those of a control group of 30 normal men, and their basal serum luteinizing hormone concentrations and serum luteinizing hormone responses to synthetic gonadotropin-releasing hormone were only slightly higher than those of the normal men. The mean sperm density of the patients, however, was only one third of that of the normal men (p less than 0.001). The mean serum follicle stimulating hormone response ro gonadotropin-releasing hormone of the patients was doubled that of the normal men (p less than 0.001). The data indicate that spermatogenesis may be abnormal after orchipexy, and suggest that men with unilaterally undescended testis may have bilateral testicular abnormality.  相似文献   
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A slide latex agglutination (SLA) assay was developed for rapid screening for Clostridium perfringens type A enterotoxin (CPE). SLA specifically detected CPE added to buffer or normal feces (sensitivity limit of 1 μg CPE/g feces). Using clinical fecal samples from C. perfringens food poisoning cases, a strong correlation was shown between (1) SLA results and results from other CPE assays and (2) between SLA results and illness status.  相似文献   
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Morphine sulfate effects (30 mg, intramuscularly) on cerebral glucose utilization and subjective self-reports were examined in 12 polydrug abusers by positron emission tomography and [fluorine 18]fluorodeoxyglucose in a double-blind placebo-controlled crossover study. During testing, subjects sat with eyes covered, listening to white noise and "beep" prompts. Morphine significantly reduced glucose utilization by 10% in whole brain and by about 5% to 15% in telencephalic areas and the cerebellar cortex, assuming no contribution of hypercapnia. When the contribution of PaCO2 (45 minutes after morphine was administered) was partialled out, significant morphine-induced reductions persisted in whole brain and six cortical areas. Irrespective of morphine, left-greater-than-right asymmetry occurred in the temporal cortex, and an interaction between hemisphere and drug was noted in the postcentral gyrus. In most cases, effects on glucose utilization were not significantly related to measures of euphoria.  相似文献   
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In their core curriculum guidelines, the Society of Teachers of Family Medicine has recognized the importance of training family physicians in caring for persons with mental retardation. We mailed surveys to all family practice residency directors in the United States, questioning them about experiences and methods used to teach residents about health care needs of adults with mental retardation and the importance of this education. We found that 84% of programs provide residents with one or more experiences, and 60% instruct residents in this area. Most directors ranked this education as very important or important. There was no relationship between type or age of residency program and likelihood that residents were educated about mental retardation. The importance of this education is discussed.  相似文献   
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Inositol 1,4,5-trisphosphate receptors (IP3R) are mediators of second messenger-induced intracellular calcium release. Three isoforms are known to be expressed in brain, but their regional distributions and cellular localizations are little known. In order to better understand the roles of IP3 receptor isoforms in brain function, a first step is to define their distributions. We have used affinity-purified antibodies directed against peptides unique to each isoform to determine their sites of expression in rat brain. Type 1 IP3R (IP3R1) is dramatically enriched in Purkinje neurons in cerebellum and neurons in other regions, consistent with previous studies. By contrast, IP3R2 is only detected in glia, whereas IP3R3 is predominantly neuronal, with little detected in glia. IP3R3 is enriched in neuropil, especially in neuronal terminals (which often contain large dense core vesicles) in limbic and basal forebrain regions including olfactory tubercle, central nucleus of the amygdala, and bed nucleus of the stria terminalis. In addition, IP3R1 and IP3R3 have clearly distinct time courses of expression in developing brains. These data suggest separate roles for inositol 1,4,5-trisphosphate receptor isoforms in development, and for glial and neuronal function. The IP3R3 may be involved in regulation of neurotransmitter or neuropeptide release in terminals within specific nuclei of the basal forebrain and limbic system.  相似文献   
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