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41.
P H Stein  M A Rees  A Singer 《Transplantation》1992,53(6):1347-1352
The NOD mouse develops immune-mediated diabetes mellitus characterized by T cell infiltration and destruction of pancreatic islet tissue. We wished to determine whether one contributing factor was an abnormality of the NOD pancreas that caused it to elicit an attack by NOD T cells. Therefore we constructed mice that had an NOD immune system and a non-NOD host pancreas. We found that these animals with only an NOD immune system developed both insulitis and diabetes in their non-NOD pancreas. We conclude that the NOD pancreas is not unique in its ability to elicit an autoimmune attack from NOD T cells.  相似文献   
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Analytical flow cytometry was used to study circulating prostate specific antigen (PSA)-positive cells in 40 consecutive patients with newly diagnosed, untreated prostate cancer; 25 patients (63%) had metastatic disease confirmed by a positive bone scan. Cell suspensions were prepared for each patient from both the primary tumour and peripheral blood samples. The cells were stained with a monoclonal antibody against PSA, and analysed by flow cytometry; PSA-positive cells were sorted according to their immunofluorescence and light scatter properties. The cellular deoxyribonucleic acid (DNA) content of each specimen was also analysed to establish ploidy status. PSA-positive cells were detected in the peripheral blood of 33 patients (83%). The presence of these cells in the circulation showed a higher degree of sensitivity and specificity in predicting positive bone scans than did serum PSA levels. Circulating PSA-positive cells may represent either a subpopulation of tumour cells with distinct metastatic properties or, alternatively, host immunocytes which take up PSA in an active or passive manner.  相似文献   
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The utility of rank transformation followed by parametric analysisof the ranks has been assessed for determination of the statisticalsignificance of genotoxicity data. Both non-parametric and parametricanalytical methods have defects when used to assess the significanceof results from routine regulatory tests. Superficially, therank transformation method followed by parametric analysis ofranks appears to be an ideal solution. However, we consideredthat such a test might suffer a substantial loss of power whenused to analyse normally distributed data with very low samplereplication. To test this hypothesis we took 22 data sets fromfive ‘borderline’ positive compounds in mouse lymphomatreat-and-plate assays where treatment-related increases werebetween 1.5- and 3-fold the control and analysed these resultsby Dunnett's t-test using rank transformed data and weighted,untransformed data. In theory these mouse lymphoma data shouldshow the rank transformation system at its worst in comparisonwith parametric methodology using weighted data. Surprisingly,the rank transformation methodology showed no loss of powerand, overall, performed more consistently than the weighteddata methodology. Based on this limited number of data sets,rank transformation followed by parametric analysis of ranksseems to be an approach very suitable for genotoxicity assaysin general, particularly where distributions are non-normalor of uncertain form. It combines the general applicabilityof non-parametric methods with the power of parametric analyses.However, the methodology still requires to be further validatedin use and by computer simulation.  相似文献   
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AIM: To investigate women's perceptions of the contribution of cardiac rehabilitation to their recovery from a myocardial infarction. BACKGROUND AND PURPOSE: Cardiac rehabilitation programs have been based on research with almost exclusively male participants. It was unclear if cardiac rehabilitation programs meet the needs of women. METHOD: Ten women who had experienced one or more myocardial infarctions were interviewed. Data from these interviews were analysed using Glaserian grounded theory. FINDINGS: The core category that emerged from the data was 'regaining everydayness'. Participants worked to regain their 'everydayness' through a basic social process of 'reframing'. Reframing involved coming to terms with what they had experienced and fitting it into their lives. Other categories related to symptom recognition and recovery. CONCLUSION: Cardiac rehabilitation programs contributed to overall recovery from a myocardial infarction in different ways for each participant. Although programs provided information for participants, they failed to provide the type of support needed to effectively aid reframing and recovery. Programs did not meet the needs of all participants and it was apparent that one size does not fit all.  相似文献   
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BACKGROUND: Risperidone has been shown to be clinically effective for the treatment of aggressive behavior in children, yet no information is available regarding whether risperidone exhibits aggression-specific suppression in preclinical studies that use validated developmentally immature animal models of escalated aggression. Previously, we have shown that exposure to low doses of the psychostimulant cocaine-hydrochloride (.5 mg/kg intraperitoneally) during the majority of pubertal development (postnatal days [P]27-57) generates animals that exhibit a high level of offensive aggression. This study examined whether risperidone exerts selective aggression-suppressing effects by using this pharmacologic animal model of highly escalated offensive aggression. METHODS: Experimental hamsters were tested for offensive aggression after the acute administration of risperidone (.05-1.0 mg/kg, intraperitoneally). RESULTS: Risperidone dose-dependently reduced the highly aggressive phenotype, with a significant reduction observed at .1-.2 mg/kg for most aggressive responses measured. Experimental animals treated with higher doses of risperidone (.3-1.0 mg/kg) showed significant reductions in aggression and social interest toward intruders, indicating more general behavioral inhibition. CONCLUSIONS: These studies provide evidence that risperidone exerts specific aggression-suppressing effects in a developmentally immature animal model of escalated aggression.  相似文献   
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The diagnosis of molar pregnancy is a continuing diagnostic problem for many practicing histopathologists who are required to examine specimens of products of conception, particularly since changes in gynecological management in recent years have resulted in uterine evacuation at earlier gestations. The aim of this review is to provide practical, up-to-date, diagnostically useful information regarding the histological diagnosis of molar disease in early pregnancy. Pathophysiological issues relevant to molar pregnancies, such as genetic abnormalities, will be briefly summarized, but nonhistopathological aspects of molar disease will not be covered in detail in this review.  相似文献   
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