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Apoptosis: molecular regulation of cell death   总被引:1,自引:0,他引:1  
This article focuses on the few disorders that produce chronic cholestasis in infants and children. Cholestasis is defined, and a framework for thinking about pathophysiology is provided. Medical management is discussed in the context of the consequences and complications of chronic cholestasis. The limited differential for chronic cholestasis is discussed, and approaches to diagnosis and management of specific disorders are provided.  相似文献   
996.
To inform nursing professionals about their role in the prevention of traffic accidents, a grave health-related problem, is the purpose of this article. To begin with, factors which can deteriorate one's capacity to drive vehicles, and over which nursing professionals can intervene, will be presented. These factors include alcohol, other drugs, medicines, individual morbidity, the factor of aging and the use of security devices. A special reference will be made about widely used medicines. Finally the role that a nurse can fulfill will be explained. This role can be directed to various sections of the general public, be of varying natures, be exercised with greater or lesser ease, and lastly can have more or less effect upon those to whom it is destined.  相似文献   
997.
The etiology of the selective neuronal death that occurs in Huntington's disease (HD) is unknown. Several lines of evidence implicate the involvement of energetic defects and oxidative damage in the disease process, including a recent study that demonstrated an interaction between huntingtin protein and the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH). Using spectrophotometric assays in postmortem brain tissue, we found evidence of impaired oxidative phosphorylation enzyme activities restricted to the basal ganglia in HD brain, while enzyme activities were unaltered in three regions relatively spared by HD pathology (frontal cortex, parietal cortex, and cerebellum). Citrate synthase-corrected complex II-III activity was markedly reduced in both HD caudate (-29%) and putamen (-67%), and complex IV activity was reduced in HD putamen (-62%). Complex I and GAPDH activities were unaltered in all regions examined. We also measured levels of the oxidative damage product 8-hydroxydeoxyguanosine (OH8dG) in nuclear DNA, and superoxide dismutase (SOD) activity. OH8dG levels were significantly increased in HD caudate. Cytosolic SOD activity was slightly reduced in HD parietal cortex and cerebellum, whereas particulate SOD activity was unaltered in these regions. These results further support a role for metabolic dysfunction and oxidative damage in the pathogenesis of HD.  相似文献   
998.
We observed 36 HIV-infected patients to evaluate whether the presence of tandem 2-long terminal repeat circular unintegrated HIV-1 DNA (2-LTR) in peripheral blood mononuclear cells (PBMC) at baseline was associated with acceleration of HIV disease. Detection of 2-LTR at baseline correlated with high plasma HIV-1 RNA levels (p < .01), recovery of culturable HIV-1 from plasma (p = .02), and progression to AIDS during follow-up (p = .01). More patients with 2-LTR (68%) than without 2-LTR (31%) had a decline in CD4 levels of >50 cells/mm3 over the first 18 months of follow-up (p = .04), and the average annual CD4 decline was 35% in patients with 2-LTR compared with 16% in those without 2-LTR (p = 0.06). Detection of 2-LTR in PBMC at baseline was an independent predictor of high plasma HIV-1 RNA levels and subsequent CD4 cell decline in this cohort of patients with predominantly nonsyncytium-inducing (NSI) isolates at baseline. The presence of 2-LTR in PBMC appears to be reflective of ongoing HIV-1 replication, as measured by plasma HIV-1 RNA levels, and identifies persons at risk for immunologic and clinical decline.  相似文献   
999.
Femora and tibiae of rats carrying leukemia from a LacZ-marked acute promyelocytic leukemia-derived leukemic cell line (LT12NL15) were decalcified using EDTA and routinely embedded in paraffin. Sections were used to develop for the first time an immunostaining method for LacZ, employing catalyzed reporter deposition (CARD) based on the deposition of biotinylated tyramine. This method was used to study homing and adhesion of leukemic cells.  相似文献   
1000.
OBJECTIVES: The current need to evaluate necessity and cost of diagnostic and therapeutic procedures extends to transplant services. We reviewed our experience over the past 3 years as we have moved away from routine post-transplant nuclear medicine scans, ultrasounds, and cystograms. METHODS: From January 1, 1992 to December 31, 1994, 252 kidney transplants were performed at Virginia Mason Medical Center. There were 74 live donor and 178 cadaver donor kidneys transplanted. The records of these patients were reviewed for the type and number of post-transplant imaging done during their initial hospitalization. RESULTS: During the study period, the number of post-transplant imaging studies per patient decreased from 2.7 to 1.4 (P = 0.000), the percentage of patients discharged without any studies rose from 2.8% to 24.4% (P = 0.001), and the trend in 1-year actual graft survival increased from 84.7% to 93.0% (P = 0.187). CONCLUSIONS: Post-transplant imaging studies can be safely reduced. Many patients with good initial graft function can avoid having any studies.  相似文献   
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