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101.
StudyontheRelationshipbetweenCytogeneticsandPhenotypicEffectinTurner'sSyndromeHUXiaofeng(胡晓峰);ZHUBaosheng(朱宝生);LINHanhua(林汉华)...  相似文献   
102.
Treatment of confluent monolayers of human umbilical vein endothelial cells with sublethal concentrations of hydrogen peroxide (H2O2) produces reversible cell retraction that opens gaps between adjacent cells. Despite the retraction, adjacent cells remain in contact through a network of dendrite-like processes. Retraction depends on cellular metabolism but not new protein synthesis or protein kinase C. Shape changes induced by H2O2 are accompanied by partial redistribution of actin filaments from the cell periphery in resting endothelial cells to a tangled network of centrally located filaments in H2O2-treated endothelial cells. This change in actin organization is associated with a loss of the normal distribution pattern of surface protein expression. Specifically, beta 1 and beta 3 integrins partly escape from focal adhesion plaques and migrate to the lateral and apical surface of the cell; PECAM-1 redistributes from the lateral borders to the basal surface; and ICAM-1 and ICAM-2 spread from apical caps to the basal surface and to the dendrite-like processes. The likely consequence of endothelial retraction accompanied by abnormal membrane protein distribution is a loss of normal endothelial cell functions. These changes are best considered manifestations of H2O2-induced sublethal injury that may cause endothelial dysfunction.  相似文献   
103.
The surgical management of lobular carcinoma in situ (LCIS) and ductal carcinoma in situ (DCIS) remains controversial. For in situ breast cancer local excision (LE), local excision and radiation therapy (LERT) and mastectomy (MAST) have all been advocated. A search of the English literature found 13 reports concerning the surgical management of LCIS and 12 reports concerning the management of DCIS. The data were combined in a meta-analysis of outcome. As expected, recurrence rates following LE with both LCIS 8.4%) and DCIS (17%) are high. However,the overall mortality following mastectomy for recurrence, LCIS (2.8%) and DCIS (2.3%) does not differ statistically from those treated initially with mastectomy for LCIS (0.9%) and DCIS (1.7%). We conclude from these data that local recurrence after breast conserving procedures for in situ breast cancer does not carry an ominous prognosis. This knowledge should aid in planning individual therapy.  相似文献   
104.
EffectsofPhentolamineonHemorrheologyandHemodynamicsinDogswithAcuteLiverDamageDANZili(但自力);ZHANGWenying(张文英);LIShaobai(李绍白)(In...  相似文献   
105.
106.
The decrease in membrane microviscosity of erythrocyte ghosts in the presence of clinically relevant concentrations of seven inhalation anaesthetic agents was studied using fluorescence polarization anisotropy of the membrane incorporated fluorescent probes 1,6-diphenyl- 1,3,5-hexatriene and 1-[4-trimethylammoniumphenyl]-6-phenyl-1,3,5- hexatriene. All anaesthetic agents produced a dose-dependent decrease in anisotropy of both probes, indicating decreased membrane microviscosity. The reduction in anisotropy measured at the minimum alveolar concentration (ED50) for anaesthesia was related inversely to the anaesthetic potency of the agent and was directly proportional to the hypothetical concentration of agent in the membrane calculated from lipid-water partition coefficients. These findings do not support the hypothesis that volatile anaesthetic agents act by increasing membrane microviscosity of the bulk lipid bilayer to produce anaesthesia.   相似文献   
107.
Our randomized double blinded comparison of acetaminophen versus analgesic and antiinflammatory doses of ibuprofen in the treatment of 182 subjects with knee osteoarthritis (OA) systematically evaluated soft tissue tenderness and joint swelling. Improvement in these signs of joint inflammation was associated with lessening of disability (p = 0.02), and reduction in rest pain (p = 0.07), but not with the drug treatment regimen. Thus, joint tenderness and swelling, presumptive evidence of synovitis, may not be a priori indications for use of an antiinflammatory drug, or predict greater responsiveness to treatment with an antiinflammatory drug than to a pure analgesic, in symptomatic treatment of patients with knee OA.  相似文献   
108.
女性飞行学员高空飞行生理生化耐受能力研究   总被引:1,自引:0,他引:1  
为从高空缺氧耐力训练前后生理、生化角度探讨中国女飞行员驾驶战斗机的可行性,在地面模拟高空缺氧及高空飞行训练前后行心电图、心率、血氧饱和度、血压、血尿酸(BUA)、肌酸激酶(CK)、血红蛋白(Hb)、乳酸(BLA)、肌酐(Cr)和天冬氨酸转氨酶(AST)测定,并与男飞行学员的测定结果比较.发现男女飞行学员的心电图、心率、血氧饱和度、血压、Cr、CK、BUA和AST均无显著性差异;女飞行学员在高空耐缺氧Hb代偿反应高于男飞行学员(P<0.05),而BLA水平低于男飞行学员(P<0.05).认为中国女飞行学员在生理生化耐受能力上能胜任飞战斗机.  相似文献   
109.
Acute stroke affects large numbers of people worldwide. It causes significant morbidity and mortality. Data support the hypothesis that the public is not familiar with either the risk factors or the signs of stroke. Educating the public about stroke may result in a lower incidence of the disease as individuals modify their risk factors, and in improved outcomes as a result of reductions in delays to treatment. There is clear and convincing evidence that reducing delays to treatment of patients with acute stroke results in improved outcomes. Public education programs should be broad-based, tailored to individual audiences, and carry a common theme.  相似文献   
110.
The establishment and characterization of 11 human lung cancer cell lines are described in this article. Nine of these cell lines were established over a 5-year period, from 1983 to 1988, from patients treated at the Kingston Regional Cancer Centre. These include eight definite or probable small cell lung cancer (SCLC) lines and one adenocarcinoma line. In addition, two other SCLC cell lines were characterized. All of the lines have been in continuous culture for more than 2 years. The clinical histories of the patients from whom the cell lines were derived are outlined here. Several features of the cell lines are presented, including the following: (1) a comparison of the histologic features of the cell lines with the original biopsy specimens; (2) the expression of various markers, including cytokeratin, carcinoembryonic antigen, calcitonin, and neuron-specific enolase; (3) activities of the enzymes l-dopa decarboxylase and the brain isoenzyme of creatine kinase; (4) growth characteristics; (5) cloning efficiency in soft agar; (6) tumorigenicity in nude mice; and (7) cytogenetic studies. These cell lines, obtained directly from patients with a spectrum of drug-sensitive and drug-resistant tumors, will be valuable in vitro models of sensitivity and resistance to chemotherapy in lung cancer.  相似文献   
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