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Immunoreactivities (IR) of substance P and leucine enkephalin have been demonstrated in the guinea-pig paracervical ganglion by an immunogold electron microscope method. Both substance P-IR and leucine enkephalin-IR were detected in large synaptic vesicles with electron-dense cores. The former neuropeptide was detected in nerve terminals and varicosities comprised mainly of large vesicles with electron-dense cores; the latter was detected in nerve terminals and varicosities that also included small, clear synaptic vesicles. In a minority of nerve terminals and varicosities coexistence of both immunoreactivities could be demonstrated within vesicles with an electron-dense core. Also present in these nerve terminals and varicosities were small, clear synaptic vesicles, though these were unreactive.  相似文献   
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Commercially available serotonin-type 3 (5-HT3) receptor antagonists (ondansetron, granisetron, and tropisetron) have shown no clinically significant adverse effects on the cardiovascular system. In the dose-ranging evaluation of dolasetron, computer-generated ECGs revealed clinically asymptomatic prolongations of ECG intervals. We performed a clinical trial in which the possible changes in ECG intervals following a single 3-mg i.v. injection of granisetron and an injection of either doxorubicin or epirubicin were registered using computerized ECG analysis in cancer patients. A total of 30 patients who were designated to receive 3 mg granisetron i.v. for the prophylaxis of emesis induced by doxorubicin or epirubicin were entered into the study. Computer-generated ECG tracings were obtained before treatment, following the injection of 3mg granisetron, and immediately after doxorubicin or epirubicin injection. The mean PR interval duration increased from 160 to 166 ms after granisetron infusion (P=0.02). Doxorubicin and epirubicin did not potentiate this change. There was no statistically significant change in cardiac rhythm, QRS duration, or QTc intervals. The observed minor changes in the PR time following i.v. injection of granisetron do not seem to be of clinical relevance.  相似文献   
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This study attempted to identify the determinants of acute lower respiratory-tract infections (ALRI) among children under five years of age, by comparing hundred children hospitalized with ALRI with a control group. Data on socio-demographic, biological and environmental characteristics were collected by interviewing mothers and anthropometric measurements were carried out to assess the nutritional status of the children. Risk of disease in the presence of each exposure was calculated in the univariate analysis and the best explanatory variables among them were identified in the multivariate analysis. The following variables were found to increase the risk of ALRI: (1) history of wheezing, (2) low birth weight, (3) passive smoking, (4) male sex, (5) delivery by cesarean section (6) sharing of sleeping space, (7) not being exclusively breast fed upto the completion of four months, (8) stunting, (9) having pets. The findings highlight some simple strategies which would help in prevention of ALRI.  相似文献   
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