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71.
Loss of heterozygosity for distal markers on 22q in human gliomas.   总被引:5,自引:0,他引:5  
Loss of constitutional heterozygosity as determined through the analysis of restriction-fragment-length polymorphism (RFLP) on tumoral and constitutional DNA has proven to be helpful to delimit the location of tumor-suppressor genes in the human genome. In malignant gliomas this approach indicates that chromosomes 9p, 10, 17p, and 22 may contain genes of this category involved in its origin and/or progression. Regarding chromosome 22, the data so far provided by molecular studies confirmed those previously reported by cytogenetic studies, suggesting the existence of a sub-group of malignant gliomas characterized by monosomy of this chromosome. However, the precise location of the putative glioma suppressor gene on chromosome 22 remains ambiguous. We have performed a combined cytogenetic and RFLP study on a series of 31 gliomas, looking for structural abnormalities of this chromosome. In 3 instances, terminal deletions of the long arm of chromosome 22 were observed by both methodologies, suggesting that the band q13 region distal to the D22S80 marker might be the critical domain non-randomly involved in tumor suppression of gliomas.  相似文献   
72.
大学生生涯规划及其对护理教育的意义   总被引:1,自引:0,他引:1  
对大学生生涯规划及国内外研究状况进行综述,指出生涯规划对护理教育的意义,提出在高等护理教育中加强大学生的生涯规划将是我国护理教育的主要发展方向之一。  相似文献   
73.
74.
BACKGROUND: This study investigated the utility of the alveolar - arterial oxygen pressure difference (AaDO (2)) in predicting the short-term prognosis of acute pulmonary embolism (PE). METHODS AND RESULTS: This study retrospectively enrolled 114 consecutive patients with acute PE, diagnosed by either spiral computed tomography or high probability ventilation - perfusion lung scans. During the first 24 h of admission, all patients had initial artery blood gas collected under room air. Patient exclusion criteria were chronic lung disease, septic emboli, and moderate and low probability lung scans. Patients were assigned to 2 groups based on either 30-day death or a 30-day composite event. Receiver operating characteristic analyses was used to determine the AaDO(2) cut-off value for predicting primary and composite endpoints. Statistical analysis demonstrated significant differences in AaDO(2) between the 30-day composite endpoint group and the 30-day composite event-free survival group (p=0.012). The AaDO(2) had a strong trend between the 30-day death group and the survival group (p=0.062). The best cut-off value for AaDO(2) was 53 mmHg and using this, the positive predictive value for 30-day death was 25% and the negative predictive value was 92%. For the 30-day composite endpoint, the positive predictive value for AaDO(2) was 35%, and the negative predictive value was 84%. In this study, thrombocytopenia was also an indicator of poor prognosis for patients with acute PE. CONCLUSION: The AaDO(2) measurement is a highly useful and simple measurement for predicting short-term prognosis in patients with acute PE. It has high negative predictive value and moderate positive predictive value for 30-day death and 30-day composite event. Aggressive thrombolytic treatment strategies should be considered for patients with an initial poor prognostic parameter (ie, AaDO(2) >or=53 mmHg).  相似文献   
75.
76.
Stress is known to be one of the risk factors of stroke. Most of the knowledge on the effects of stress on cerebrovascular disease in humans is restricted to catecholamines and glucocorticoids effects on blood pressure and/or development of atherosclerosis. However, few experimental studies have examined the possible mechanisms by which stress may affect stroke outcome. We have used an acute stress protocol consisting of the exposure of male Fischer rats to an acute, single exposure immobilisation protocol (6 h) prior to permanent middle cerebral artery occlusion (MCAO), and we have found that stress worsens behavioural and neurological outcomes and increased infarct size after MCAO. The possible regulatory role of the TNFalpha and IL-1beta was studied by looking at the release of these cytokines in brain. The results of the present study showed an increase in IL-1beta release in cerebral cortex after exposure to acute stress. Brain levels of IL-1beta are also higher in previously stressed MCAO rats than in MCAO animals without stress. Pharmacological blockade of IL-1beta with an antibody anti-IL-1beta led to a decrease in the infarct size as well as in neurological and behavioural deficits after MCAO. In summary, our results indicate that IL-1beta, but not TNFalpha, accounts at least partly for the worsening of MCAO consequences in brain of rats exposed to acute stress.  相似文献   
77.
78.
Migration and proliferation of vascular smooth muscle cells are early and major events in the formation of atherosclerotic lesions. We report on an aorta transplant model in rabbits wherein myointimal proliferation is inhibited by 17-beta-estradiol. The abdominal aortas of outbred white New Zealand rabbits were harvested and allografted to the carotid artery of the recipient. The animals, which were fed either a normal or a high-cholesterol (0.5%) diet, were killed 3 weeks later. The degree of myointimal proliferation was measured with a digitized system attached to a light microscope. The myointimal hyperplasia was expressed as the cross section area of the intima/the area of the intima + the area of the media x 100. Transmission electron micrographs were obtained for all vessels. Intimal thickening was shown mainly to consist of proliferating smooth muscle cells. The cholesterol diet resulted in significantly higher serum total cholesterol levels compared to animals on a normal diet (p < 0.0001) but did not affect serum high-density lipoprotein-cholesterol or serum triglyceride levels. The cholesterol diet was also associated with a greater but not significant amount of intimal thickening. Treatment with 17-beta-estradiol significantly decreased both serum triglyceride concentration (p < 0.05) and myointimal thickening (p < 0.01) in cholesterol-fed animals. Transmission electron microscopy showed that the endothelial cells appeared structurally normal in the estradiol-treated animals. Further, estradiol prevented the appearance of vacuolized macrophages. Thus estradiol may decrease myointimal thickening by preserving the endothelium and preventing macrophage appearance in the intima.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
79.
Abstract: Hydantoin is an anticonvulsant drug with several side effects. A teralogenic potential has been suggested. The fetal hydantoin syndrome is an entity that consists of a broad range of morphologic and developmental disorders in children born of epileptic mothers exposed to hydantoin during pregnancy. We treated a girl in whom onychopathy was a monosymptomatic or mild form of this syndrome.  相似文献   
80.
M Xu  B Xiong  P Cheng  Y Guo 《中国中药杂志》1992,17(4):228-30, 256
Five compounds have been isolated from the stems and leaves of Isodon albopilosus. On the basis of spectroscopic and chemical data, they were identified as macrocalyxin C, stearic acid, beta-sitosterol, ursolic acid and beta-sitosterol-beta-D-glucoside, respectively.  相似文献   
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