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81.
目的:分析血管紧张素原基因启动子区A-20C和A-6G单核苷酸多态性与蒙古族人群原发性高血压的相关性。方法:实验于2005-08/2006-01在北京华大实验室完成。选取对象均为生活在内蒙古乌拉特后旗的蒙古族牧民,三代血亲内无其他民族。采用基因测序技术对内蒙古蒙古族人群中107例原发性高血压患者和108例正常对照者进行A-20C和A-6G基因分型,观察高血压组和正常对照组不同基因型的分布和等位基因频率的差异。结果:①两组受试者在性别、年龄及吸烟、饮酒、体质量指数和临床化验检查指标有较好的匹配(P均>0.05)。②两组血管紧张素原基因A-20C位点AA,AC,CC基因型频率比较差异无显著性意义(高血压组分别为0.51,0.29,0.20;正常对照组分别为0.49,0.28,0.23,χ2=0.395,P=0.529)。A,C等位基因频率比较差异无显著性意义(高血压组分别为0.65,0.35;正常对照组分别为0.63,0.37,χ2=0.015,P=0.904)。③两组血管紧张素原基因A-6G位点AA,AG,GG基因型频率比较差异无显著性意义(高血压组分别为0.50,0.33,0.17;正常对照组分别为0.55,0.34,0.11,χ2=1.924,P=0.165)。A,G等位基因频率比较差异无显著性意义(高血压组分别为0.66,0.34;正常对照组分别为0.72,0.28,χ2=1.728,P=0.189)。④高血压组协同存在血管紧张素原基因A-20C基因型CC时,血管紧张素原基因A-6G基因型GG频率稍高于正常对照组,但差异无显著性意义(χ2=2.395,P=0.122,OR=7.52,95%CI0.014~1.250),高血压组G等位基因明显高于正常对照组(分别为0.37,0.22,χ2=4.658,P=0.034),携带该等位基因的蒙古族人群发生原发性高血压的相对危险度升高(OR=2.80,95%CI1.087~7.271)。结论:血管紧张素原基因A-20C和A-6G单核苷酸多态性与蒙古族人群原发性高血压相关,并可能具有协同作用。  相似文献   
82.
目的:调查重庆居民及流动人口结核病就诊及诊断延迟情况,探索在其过程中存在的问题,分析问题产生的原因。方法:在重庆市主城区按照经济发展水平的不同选取了两个区Y和J,采用方便抽样的方法在Y区抽取了一家综合性医院的呼吸科门诊R,在J区抽取了一家综合性医院的一般基层门诊P,于2005-10-10/14和2005-10-17/21,采用隐蔽性观察法对门诊情况进行了观察,主要观察医生和患者的相关语言、行为,了解结核病就诊及诊断延迟情况。实验得到了利物浦大学热带医学院伦理委员会的许可,并通过了重庆市卫生局的批准。资料分析采用主题框架分析法。结果:重庆居民和流动人口都存在结核病就诊延迟的情况,主要与患者的经济状况、健康意识和社会支持等因素有关;医院在结核病的诊断方面具备基本的技术和条件,诊断延迟则主要与医务人员对结核病的意识和责任心有关;另外患者自身在诊疗过程中的中途退出现象不容忽视,也是导致延迟的一个重要因素。结论:一方面综合医院缺乏对结核病患者的管理措施和意识,对结核患者重治轻管,另一方面特殊人群的患者卫生保健支付能力差,缺乏相关结核病防控知识,应依据目前的形势对相关领域进行政策倾斜和调控,积极开展对人群行之有效的健康教育。  相似文献   
83.
The c-Jun NH(2)-terminal kinase (JNK) has been implicated in both cell death and survival responses to different stimuli. Here we reexamine the function of JNK in tumor necrosis factor (TNF)-stimulated cell death using fibroblasts isolated from wild-type, Mkk4(-/-) Mkk7(-/-), and Jnk1(-/-) Jnk2(-/-) mice. We demonstrate that JNK can act to suppress TNF-stimulated apoptosis. However, we find that JNK can also potentiate TNF-stimulated necrosis by increasing the production of reactive oxygen species (ROS). Together, these data indicate that JNK can shift the balance of TNF-stimulated cell death from apoptosis to necrosis. Increased necrosis may represent a contributing factor in stress-induced inflammatory responses mediated by JNK.  相似文献   
84.
BACKGROUND: Colorectal cancer is the second leading cause of cancer death in the United States. Screening for colorectal cancer is now widely recommended but underused. Lack of insurance coverage for screening tests may be one reason patients do not undergo these procedures. OBJECTIVE: To determine the effect of Medicare reimbursement on utilization rates of invasive screening tests. Use of fecal occult blood testing was not studied before 1998. METHODS: We performed a retrospective analysis of ambulatory claims data for Washington State Medicare beneficiaries in 1994, 1995, and 1998. We determined the proportion of patients undergoing diagnostic and screening flexible sigmoidoscopy, colonoscopy, or double-contrast barium enema in 1994, 1995, and 1998 and the proportion receiving fecal occult blood testing in 1998. RESULTS: Use of diagnostic and screening colon tests was low in all years. Fewer than 6% of beneficiaries received any colon test, and fewer than 4% received a screening test. Although more patients underwent diagnostic testing after Medicare coverage began, use of screening tests did not significantly change (odds ratio, 0.99; 95% confidence interval, 0.97-1.01 comparing 1994 and 1998 [P =.33]). Women, individuals older than 80 years, and nonwhite patients were statistically significantly less likely to be screened in all 3 years (P<.001). In 1998, fewer than 7% of patients underwent fecal occult blood testing, with men and nonwhites statistically significantly less likely to have this test (P<.001). CONCLUSIONS: Colorectal cancer screening tests are underused in the Washington State Medicare population, and insurance coverage for these tests did not substantially affect utilization rates in the period studied.  相似文献   
85.
    
BACKGROUND: Tumour necrosis factor-alpha (TNF-alpha) is an important regulator of the chronic inflammation contributing to tumour progression. Infliximab, an anti-TNF-alpha monoclonal antibody was investigated in this trial of patients with advanced cancer. The primary objectives were to determine the safety profile and biological response of infliximab in a cancer population. Clinical response was a secondary objective. PATIENTS AND METHODS: Forty-one patients received infliximab at 5 mg/kg (n = 21) or 10 mg/kg (n = 20) i.v. at 0 and 2 weeks and then every 4 weeks. Post-treatment samples were measured for changes in plasma and serum TNF-alpha, CCL2, IL-6 and C-reactive protein (CRP). RESULTS: Infliximab was well tolerated with no dose-limiting toxic effects. At both doses of infliximab, neutralisation of serum TNF-alpha was observed after 1 h while plasma CCL2, IL-6 and serum CRP were decreased 24 and 48 h following infliximab administration. Seven patients experienced disease stablisation (range 10-50+ weeks). There was no evidence of disease acceleration in any patient. CONCLUSIONS: Infliximab treatment was safe and well tolerated in patients with advanced cancer. There was evidence of biological activity with baseline TNF-alpha and CCL2 being correlated with infliximab response.  相似文献   
86.
    
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87.
  总被引:17,自引:0,他引:17  
Baron  RL 《Radiology》1987,162(2):419-424
To evaluate the specificity of previously suggested computed tomographic (CT) criteria for diagnosing common bile duct (CBD) stones, CT scans of 38 patients with CBD stones were compared with scans of 32 patients with carcinoma obstructing the CBD and 28 nonobstructed patients. The CBD stone was directly visualized as a target sign or densely calcified structure in 29 of 38 patients with stones (76%); one with carcinoma showed a similar target sign. A rim of increased density in the distal CBD was found without accompanying target sign in six patients with stones (16%), compared with 12 with carcinoma (38%) and 15 nonobstructed patients (54%). Irregular intraluminal densities without a detectable target sign were noted in four patients with stones (11%), compared with eight with carcinoma (25%) and nine nonobstructed patients (32%). Abrupt termination of the CBD without a mass was more common as an isolated finding in patients with carcinoma (31%) than in patients with stones (13%). CT is accurate in detecting CBD stones in certain patient populations, but direct visualization of the stone is required.  相似文献   
88.
  总被引:1,自引:0,他引:1  
Magnetic resonance (MR) imaging systems produce spatial distribution estimates of proton density, relaxation time, and flow, in a two dimensional matrix form that is analogous to that of the image data obtained from multispectral imaging satellites. Advanced NASA satellite image processing offers sophisticated multispectral analysis of MR images. Spin echo and inversion recovery pulse sequence images were entered in a digital format compatible with satellite images and accurately registered pixel by pixel. Signatures of each tissue class were automatically determined using both supervised and unsupervised classification. Overall tissue classification was obtained in the form of a theme map. In MR images of the brain, for example, the classes included CSF, gray matter, white matter, subcutaneous fat, muscle, and bone. These methods provide an efficient means of identifying subtle relationships in a multi-image MR study.  相似文献   
89.
    
High quality 31P MR spectra (signal to noise ratio (S/N) approximately 18, 15 min acquisition for each spectrum) were consistently obtained with surface coils over a period of 6-week RT. Both transient and steady state alterations in metabolites in response to RT were found in this case. The transient changes occurred during the first 3 hr immediately after the 3rd fractionated RT, these changes include the transient elevation of the PCr resonance, a decrease in PDE and an increase in intracellular pH. The monitoring showed that the metabolites approached steady state approximately 2 hr after the fractionated radiation intervention, suggesting that in vivo MRS can be useful for studying the dynamics of tumor response to RT such as repair of potential lethal damage, growth delay, and reoxygenation etc. The steady-state MR spectra showed the net response to each intervention and can clinically be useful for predicting and measuring the result of the fractionated RT. In this case study, the PDE peak which contains the phospholipid metabolites GPC and GPE, is the most sensitive resonance in response to RT. After the 3rd RT, prior to tumor size reduction, the PDE to ATP ratio decreased 33% and intracellular pH increased to 7.34 +/- 0.05 from 7.27 +/- 0.05. In the subsequent RT interventions, both the tumor size and PDE/ATP ratio continually decreased whereas the pH values remained alkaline and fluctuated around 7.34 to 7.65. The data suggest that the phospholipid metabolite PDE may signal important alterations in membrane metabolism that eventually lead to cell death.  相似文献   
90.
  总被引:11,自引:0,他引:11  
  相似文献   
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