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排序方式: 共有5325条查询结果,搜索用时 15 毫秒
21.
Polymorphic MHC ancestral haplotypes affect the activity of tumour necrosis factor-alpha. 总被引:7,自引:0,他引:7 下载免费PDF全文
It remains unclear which MHC loci are involved in susceptibility to autoimmune diseases and immune deficiencies. We have chosen to evaluate whether different alleles of tumour necrosis factor-alpha (TNF-alpha) are important, as TNF has been implicated in the etiology of many immunological disorders. We have shown previously that a restriction fragment length polymorphism in the TNF region correlates with MHC ancestral haplotypes. We therefore examined the effect of ancestral haplotype on the activity of TNF-alpha in culture supernatants of lymphoblastoid cell lines. The results demonstrate that TNF-alpha activity in supernatants of 8.1 (A1, B8, DR3) cell lines was higher than that present in the supernatants from cells homozygous for eight different MHC ancestral haplotypes, and indicate that polymorphisms in TNF-alpha, or in other MHC genes that regulate TNF, may be responsible for the 8.1 phenotype. 相似文献
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Relationship between fatty liver and subsequent development of necrosis, inflammation and fibrosis in experimental alcoholic liver disease 总被引:4,自引:0,他引:4
Rats fed a diet varying in the amount of fat, infused with ethanol, were studied to determine the relationship among diet, degree of fatty liver, and development of necrosis, inflammation, and fibrosis. Three groups of experimental animals, male Wistar rats, were fed diets containing 25% fat, 35% fat, and 32% fat with low protein. Morphologic assessment of liver injury was performed monthly by obtaining liver biopsies. The greatest degree of fatty infiltration at 1 month was seen in the high fat-low protein group, the mean fat score (3.8 +/- 0.37) was significantly higher than in the other two groups (P less than 0.05 and P less than 0.01). When the subsequent development of necrosis, inflammation, and fibrosis was related to the degree of fatty infiltration at 1 month, a significant relationship was seen between the number of animals developing these pathologic lesions and the severity of fatty liver. Our results show that the degree of fatty infiltration of the liver, influenced by the dietary intake of both fat and protein, is related to the subsequent development of necrosis, inflammation, and fibrosis in our intragastric feeding model for alcoholic liver disease. 相似文献
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Clinical experience with cytomegalovirus isolation using conventional cell cultures and early antigen detection in centrifugation-enhanced shell vial cultures. 总被引:1,自引:5,他引:1 下载免费PDF全文
A total of 1,915 clinical samples was inoculated by low-speed centrifugation into shell vials (Bartels Immunodiagnostics, Bellvue, Wash.) containing cover slip monolayers of MRC-5 fibroblasts. At 1 and 2 days postinoculation, one cover slip was stained by an indirect immunofluorescence technique using a monoclonal antibody (Biotech Research Laboratories for Dupont, Billerica, Mass.) to cytomegalovirus (CMV) early antigen (EA). Clinical samples were also inoculated into three MRC-5 or MRHF cell cultures which were observed for 30 days for the appearance of a cytopathic effect (CPE). Of 157 CMV-positive samples, 92 (59%) were identified by centrifugation-enhanced EA (CE-EA) and 131 (83%) produced a CPE. CE-EA was less sensitive than CPE for all types of samples, although 17% of CMV-positive samples were detected by CE-EA alone. Evaluation of the CMV status of patients with CE-EA-positive-CPE-negative samples indicated that these samples likely represented true CMV-positive results. The average elapsed time between culture inoculation and identification of CMV decreased as follows when both CE-EA and CPE, rather than CPE alone, were used: urines, 15 to 7 days; buffy coats, 18 to 9 days; lung samples, 13 to 8 days; throat samples, 18 to 7 days. Although CE-EA was less sensitive than 30-day cell culture, both CE-EA and CPE were identified as valuable in CMV detection, and neither could be discontinued without a decrease in the CMV isolation rate or an increase in the turnaround time. 相似文献
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Michael W. O'Hara Claudia J. French Ellen M. Zekoski Danny J. Neunaber Gary W. Schroeder 《Cognitive therapy and research》1985,9(3):267-275
According to the reformulated learned helplessness model of depression, causal attributions are an important mediator of the effects on mood of positive and negative experiences. Adaptive attributions for negative events are assumed to be external, unstable, and specific. In the present study, subjects exposed to one of two attribution training procedures or a control condition made attributions for hypothetical events under neutral and adaptive instructional sets. Attributions were rated by subjects and coders blind to the purpose of the study. Results indicated that subjects' views of adaptive causal attributions were congruent with predictions from the learned helplessness model. The ratings of the objective coders indicated that subjects' attributions really did change in response to the adaptive instructions in the predicted direction. Implications of these results for the reformulated learned helplessness model and depression therapies that include an attribution retraining component are discussed.The authors would like to thank Dan Russell for his very helpful comments on earlier drafts of this paper. 相似文献
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Lange Rael T. French Louis M. Bailie Jason M. Merritt Victoria C. Pattinson Cassandra L. Hungerford Lars D. Lippa Sara. M. Brickell Tracey A. 《Quality of life research》2022,31(8):2411-2422
Quality of Life Research - This study examined the clinical utility of post-traumatic stress disorder (PTSD), low resilience, poor sleep, and lifetime blast exposure as risk factors for predicting... 相似文献
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Pippa Grenfell Nerissa Tilouche Jill Shawe Rebecca S. French 《Sociology of health & illness》2021,43(1):116-132
Fertility awareness apps, which help to identify the ‘fertile window’ when conception is most likely, have been hailed as ‘revolutionising’ women’s reproductive health. Despite rapidly growing popularity, little research has explored how people use these apps when trying to conceive and what these apps mean to them. We draw on in‐depth, qualitative interviews, adopting a critical digital health studies lens (a sub‐field of science and technology studies), to explore the experiences of cisgender women and partners with one such app, Natural Cycles, in the context of their daily lives. We found that many women valued the technology as a ‘natural’, inobtrusive alternative to biomedical intervention, and a means of controlling and knowing their bodies, amid a dearth of fertility‐related education and care. Yet this technology also intervened materially and affectively into the spaces of their lives and relationships and privileged disembodied metrics (temperature) over embodied knowledge. Meanwhile, app language, advertising and cost have contributed to characterising ‘typical’ users as white, heterosexual, affluent, cisgender women without disabilities. In the context of neoliberal shifts towards bodily self‐tracking, technologies appealing as novel, liberating and ‘natural’ to individuals who can access them may nevertheless reproduce highly gendered reproductive responsibilities, anxieties and broader health and social inequalities. 相似文献