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Hydroxystilbamidine (HSB) is a potent suppressor of the plaque-forming cell response of mice injected with heterologous erythrocytes. HSB, given in varying doses and injection schedules, suppressed both the primary and secondary immune responses to bovine serum albumin. Apparently the effect is not simply a toxic effect on spleen cells, because there was no appreciable difference in cell numbers between control and HSB-treated mice. The effect of HSB was most apparent in the early phase of the immune respone.  相似文献   
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HLA antigens were investigated in 41 Sicilian patients with ulcerative colitis and in 151 healthy controls. Frequencies of HLA-B5 and DR2 were increased in the group of patients with ulcerative colitis whereas the DR3 antigen frequency was decreased. However the corrected p values were not significant. Thus, present results indicate that in ulcerative colitis HLA linked genetic factors play a marginal role, if any.  相似文献   
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Racial differences in personality, behavior, and family environment of lower elementary school children were examined in a sample of 433 black and 897 white children. Numerous significant differences in scores on scales of the Missouri Children''s Picture Series, the Missouri Children''s Behavior Checklist, and the Family Environment Scale persisted after adjustment for socioeconomic status.  相似文献   
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Variation is an essential feature of biological systems. Populations adapt to dynamic environments, in part, because of this variation. In this review, we re-examine phenotypic variation, especially in organisms living in polluted environments. A recent goal of ecotoxicology is to understand the sublethal effects of exposure to pollutants, e.g. responses to endocrine-disrupting contaminants. While variation is an inherent quality of organisms, variance is a statistical measure of the variation of a trait. Increased variance has been associated with organisms living at the perimeter of a population's range, introduced into novel environments, or exposed to pollution. Some researchers have proposed increased phenotypic variance in exposed populations as an evolutionary mechanism, and others have suggested its use as a biomarker. While we agree that variance often increases in the exposed population, we also recognize that the opposite phenomenon occurs. That is, variance can decrease from exposure to pollution. Altered variance in the exposed population-leading to heteroscedasticity-could result in erroneous conclusions (Type II errors). We suggest that exposure to endocrine-disrupting contaminants could influence the health of populations in ways that are not always represented by measures of central tendency, and that variance and distribution should also be examined in environmentally stressed wildlife.  相似文献   
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Testis leiomyoma is a very rare neoplasm. It is very difficult to perform an exact preoperative diagnosis; only histological examination can prove the presence of a leiomyoma. In our case radical orchidectomy was performed because of complete substitution of normal parenchyma, the extreme rarity at long-term follow-up of a reported benign intratesticular neoplasm, and the imperfect sensitivity of the extemporary histological examination.  相似文献   
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BACKGROUND: H2-receptor antagonists are widely used in patients with gastro-oesophageal reflux disease (GERD) and are frequently continued when symptoms persist. Aim: To compare the efficacy of omeprazole 20 mg once daily with that of ranitidine 150 mg twice daily in relieving GERD symptoms, in patients who remained symptomatic following a 6-week course of ranitidine therapy. METHODS: Patients with heartburn on at least 4 days/week but who did not have endoscopy to assess oesophageal mucosa could participate. This two-phase, prospective trial included a 6-week open-label phase (phase I), followed by an 8-week double-blind phase (phase II). Patients still symptomatic following treatment with ranitidine 150 mg twice daily (phase I) were randomized to double-blind treatment (phase II) with either omeprazole 20 mg once daily or ranitidine 150 mg twice daily. The primary efficacy variable was the proportion of patients with heartburn resolution during weeks 4 and 8 of phase II. RESULTS: Of the 533 patients with GERD who received ranitidine in phase I, 348 patients (65%) were still symptomatic. A total of 317 patients (59%) were randomized to double-blind treatment (phase II). At week 8, a significantly (P < 0.0004) greater proportion of omeprazole-treated patients (70%) experienced no more than mild heartburn compared with ranitidine-treated patients (49%). Complete resolution of heartburn also occurred in a significantly (P < 0. 00001) greater proportion of omeprazole-treated patients (46% vs. 16% of the ranitidine group at week 8). CONCLUSIONS: After 6 weeks of ranitidine treatment, the majority of patients with GERD were still experiencing moderate to severe heartburn. Omeprazole was significantly more effective than ranitidine in resolving heartburn in this group of patients.  相似文献   
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