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31.
In the retina of teleost fish, cone horizontal cell axons penetrate the inner nuclear layer, where they enlarge into fusiform terminal swellings. The present study shows that horizontal cell axon terminals enlarge disproportionately during postembryonic growth of the retina in juvenile and adult goldfish: the relative volume of axon terminals increases almost 20-fold, while the volume of the entire retina increases only about fourfold during a 2-3-yr period. The enlarging axon terminals fill in the gaps created as the numerical density of nuclei in the inner nuclear layer falls. Horizontal cell axon terminals are thought to participate in cone-dominated visual pathways, although their precise role is unclear. The results of this study suggest that a comparison of horizontal cell function in small and large fish might help to resolve this issue.  相似文献   
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Both radionuclide angiography and myocardial perfusion imaging provide important insights that determine the management of patients with stable coronary artery disease. Both nuclear cardiology procedures have clearly demonstrated use in the noninvasvie identification of severe (left main or three-vessel) coronary artery disease and the noninvasive assessment of prognosis and thereby determine which patients should be sent to coronary angiography. Both radionuclide angiography and myocardial perfusion imaging provide prognostic information that is independent of resting left ventricular function and coronary anatomy and thereby influence the decision regarding which patients should be sent to coronary revascularization. This review considers the evidence supporting the uses of these nuclear cardiology procedures and provides suggestions regarding their cost-effective application.  相似文献   
35.
Rubella virus strains show no major antigenic differences.   总被引:7,自引:0,他引:7  
To determine whether antigenic differences occur among rubella virus strains, five wild-type strains of rubella virus isolated in the UK, the USA, and in Japan between 1964 and 1987 and four attenuated vaccine strains were compared employing a panel of 28 monoclonal antibodies in neutralization, haemagglutination-inhibition, enzyme immunoassay, and indirect immunofluorescence assays. No antigenic differences were detected which confirms that rubella vaccines will protect against circulating strains and that rubella antigens used in serological tests for screening and diagnosis will detect antibodies induced by all strains.  相似文献   
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PURPOSE: This study was designed to identify risk indicators for the prevalence at enrollment and incidence over 36 months of periodontal pathology and coronal caries experience affecting third molars in a community-based study of people over 65 years of age. SUBJECTS AND METHODS: Data from a subsample of 810 dentate subjects from the Piedmont 65+ Study were available for analyses. All visible teeth were examined. Periodontal probing measures were taken at 2 sites, mesiobuccal and buccal/facial. Clinical data on caries experience were collected by visual-tactile examination. At enrollment, 340 subjects had at least 1 visible third molar; all were examined for caries experience. Periodontal probing measures were available for 277 of these same subjects. The significance of the possible risk indicators for periodontal pathology and caries affecting third molars was determined by chi(2) tests. Statistical significance was set at .05. Logistic multivariable models were used to derive odds ratios and 95% confidence intervals. RESULTS: African-American subjects were more likely to have visible third molars (P < .01). Caucasian subjects were more likely to have third molar coronal caries experience (P < .01), as were subjects with greater than a high school education and those with a dental visit within 3 years (both P < .01). However, African American subjects were more likely to have periodontal pathology, CALs >/= 3 mm on third molars (P < .01), as were those who used tobacco (P < .01). None of the other risk indicators we studied were associated with progression of periodontal pathology or coronal caries experience on visible third molars. CONCLUSION: In this population study of senior adults, Caucasians and African Americans appear to have different levels of risk for caries experience and periodontal pathology affecting retained third molars.  相似文献   
39.
Thirty-seven DR4-positive patient-unrelated bone marrow donor pairs previously DR/DQ restriction fragment length polymorphism (RFLP) typed and tested in mixed lymphocyte culture (MLC), have been DR4-Dw subtyped retrospectively using sequence specific oligonucleotide probes. We found that DR4-Dw subtyping substantially increased the accuracy of pre-MLC matching and could potentially accelerate donor searches by avoiding unnecessary MLC tests on Dw-mismatched donors.  相似文献   
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Summary Data are presented on rates of admission for schizophrenia for the native born and the four largest foreign born populations living in England in 1981 (Irish, Indian, Pakistani and Caribbean born). These data show that, in general, the foreign born have higher rates of admission for schizophrenia, and a higher proportion of all diagnoses accounted for by this disorder than do the native born. The exception is Pakistani born women who have conspicuously low rates. Five hypotheses are examined to account for these differences. The apparently high rates of schizophrenia found for the Indian born of both sexes, and Pakistani born men can be accounted for to a large extent by the demographic differences that exist between them and the native born. The Irish born residents of England have rates comparable with the Irish in Ireland who also show much higher rates than do the native English. There is no completely satisfactory account for the very high rates found for Caribbean born men and women but a combination of adverse post migration experiences and tendency to misdiagnose schizophrenia in this group is offered as a tentative explanation for at least some of the excess. The low rates of admission for schizophrenia of Pakistani women is attributed to a tendency on their part to opt out of the formal mental health system after an initial encounter, possibly to return to their native land.  相似文献   
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