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991.
目的 探讨新疆农村地区COPD危险因素的特点。方法 2007年12月至2010年12月,采用统一的流行病学调查表,以整群随机抽样方法抽取新疆南部和北部农村常住人口3575人为调查对象,进行问卷调查和肺功能检测。以支气管舒张试验后FEV1/FVC< 70%,并排除其他心肺疾病作为COPD的诊断标准。采用logistic回归分析方法进行危险因素分析。结果 将资料完整的3489人纳入分析,新疆农村COPD总患病率为4.0% (138/3489),诊治率仅为14.5%(20/138),维吾尔族的检出率最高(5.1%,90/1774),其次是哈萨克族(3.3%,26/784),汉族的检出率最低(2.4%,22/921),50岁以上人群的COPD检出率明显增高(>10%,94/743)。COPD患病风险增加的因素有维吾尔族(OR=2.79,95%CI为1.71 ~4.57)、年龄>30岁(OR =3.41,95% CI为1.62~7.18)、家族呼吸系统疾病史(OR= 1.68,95% CI为1.11 ~2.53)和烹饪行为(OR= 1.47,95%CI为1.02 ~2.12)。结论 新疆农村地区COPD患病风险与维吾尔族、年龄、家族呼吸系统疾病史及烹饪行为密切相关。需进一步了解不同民族间COPD患病风险与基因的关系,以及该地区COPD患病风险与生物燃料烟雾的关系。  相似文献   
992.
ObjectivesThe aim of the study was to determine rates of mask-wearing, of respiratory infection and the factors associated with mask-wearing and of respiratory infection in healthcare workers (HCWs) in Beijing during the winter of 2007/2008.MethodsWe conducted a survey of 400 HCWs working in eight hospitals in Beijing by face to face interview using a standardized questionnaire.ResultsWe found that 280/400 (70.0%) of HCWs were compliant with mask-wearing while in contact with patients. Respiratory infection occurred in 238/400 (59.5%) subjects from November, 2007 through February, 2008. Respiratory infection was higher among females (odds ratio [OR], 2.00 [95% confidence interval {CI}, 1.16-3.49]) and staff working in larger hospitals (OR, 1.72 [95% CI, 1.09-2.72]), but was lower among subjects with seasonal influenza vaccination (OR, 0.46 [95% CI, 0.28-0.76]), wearing medical masks (reference: cotton-yarn; OR, 0.60 [95% CI, 0.39-0.91]) or with good mask-wearing adherence (OR, 0.60 [95% CI, 0.37-0.98]). The risk of respiratory infection of HCWs working in low risk areas was similar to that of HCWs in high risk area.ConclusionOur data suggest that female HCWs and staffs working in larger hospitals are the focus of prevention and control of respiratory infection in Beijing hospitals. Mask-wearing and seasonal influenza vaccination are protective for respiratory infection in HCWs; the protective efficacy of medical masks is better than that of cotton yarn ones; respiratory infection of HCWs working in low risk areas should also be given attention.  相似文献   
993.
994.
The uptake of the sulfated bile acid sulfolithocholyltaurine (SLCT) was investigated in isolated rat hepatocytes and in HeLa cells transfected with complementary DNAs (cDNAs) of organic anion transporting polypeptides (Oatps) 1 and 2 cloned from rat liver. In hepatocytes, transport of SLCT was greatly reduced by bromosulfophthalein (BSP), estrone sulfate, the precursor bile acids cholyltaurine and lithocholyltaurine, and 4,4'-diisothiocyanostilbene-2-2'-disulfonic acid (DIDS). However, SLCT transport was insensitive to 4-methylumbelliferyl sulfate, harmol sulfate, digoxin, fexofenadine, and lack of sodium ion. Because the estimation of kinetic constants was enhanced with use of inhibitors, BSP (1-50 micromol/L) was added to isolated rat hepatocytes to assess the various transport components for SLCT uptake. The resulting data showed a nonsaturable pathway and at least 2 pathways of different Michaelis-Menten constants (K(m)) (70 and 6 micromol/L) and similar maximum velocities (V(max)) (1.73 and 1.2 nmol/min/mg protein) and inhibition constants of 0.63 and 10.3 micromol/L for BSP. In expression systems, SLCT was taken up by Oatp1 and Oatp2 expressed in HeLa cells with similar K(m) values (12.6 +/- 6.2 and 14.6 +/- 1.9 micromol/L). These K(m) values were comparable to that observed for the high-affinity pathway in rat hepatocytes. In conclusion, the results suggest that transport of SLCT into rat liver is mediated in part by Oatp1 and Oatp2, high-affinity pathways, a lower-affinity pathway of unknown origin, and a nonsaturable pathway that is compatible with a transport system of high K(m) and/or passive diffusion.  相似文献   
995.
Please cite this paper as: MacIntyre et al. (2011) A cluster randomized clinical trial comparing fit‐tested and non‐fit‐tested N95 respirators to medical masks to prevent respiratory virus infection in health care workers. Influenza and Other Respiratory Viruses DOI: 10.1111/j.1750‐2659.2010.00198.x. Background We compared the efficacy of medical masks, N95 respirators (fit tested and non fit tested), in health care workers (HCWs). Methods A cluster randomized clinical trial (RCT) of 1441 HCWs in 15 Beijing hospitals was performed during the 2008/2009 winter. Participants wore masks or respirators during the entire work shift for 4 weeks. Outcomes included clinical respiratory illness (CRI), influenza‐like illness (ILI), laboratory‐confirmed respiratory virus infection and influenza. A convenience no‐mask/respirator group of 481 health workers from nine hospitals was compared. Findings The rates of CRI (3·9% versus 6·7%), ILI (0·3% versus 0·6%), laboratory‐confirmed respiratory virus (1·4% versus 2·6%) and influenza (0·3% versus 1%) infection were consistently lower for the N95 group compared to medical masks. By intention‐to‐treat analysis, when P values were adjusted for clustering, non‐fit‐tested N95 respirators were significantly more protective than medical masks against CRI, but no other outcomes were significant. The rates of all outcomes were higher in the convenience no‐mask group compared to the intervention arms. There was no significant difference in outcomes between the N95 arms with and without fit testing. Rates of fit test failure were low. In a post hoc analysis adjusted for potential confounders, N95 masks and hospital level were significant, but medical masks, vaccination, handwashing and high‐risk procedures were not. Interpretation Rates of infection in the medical mask group were double that in the N95 group. A benefit of respirators is suggested but would need to be confirmed by a larger trial, as this study may have been underpowered. The finding on fit testing is specific to the type of respirator used in the study and cannot be generalized to other respirators. Trial registration Australian New Zealand Clinical Trials Registry (ANZCTR), ACTRN: ACTRN12609000257268 ( http://www.anzctr.org.au ).  相似文献   
996.
Radiation therapy can result in bone injury with the development of fractures and often can lead to delayed and nonunion of bone. There is no prevention or treatment for irradiation-induced bone injury. We irradiated the distal half of the mouse left femur to study the mechanism of irradiation-induced bone injury and found that no mesenchymal stem cells (MSCs) were detected in irradiated distal femora or nonirradiated proximal femora. The MSCs in the circulation doubled at 1 week and increased fourfold after 4 wk of irradiation. The number of MSCs in the proximal femur quickly recovered, but no recovery was observed in the distal femur. The levels of free radicals were increased threefold at 1 wk and remained at this high level for 4 wk in distal femora, whereas the levels were increased at 1 wk and returned to the basal level at 4 wk in nonirradiated proximal femur. Free radicals diffuse ipsilaterally to the proximal femur through bone medullary canal. The blood vessels in the distal femora were destroyed in angiographic images, but not in the proximal femora. The osteoclasts and osteoblasts were decreased in the distal femora after irradiation, but no changes were observed in the proximal femora. The total bone volumes were not affected in proximal and distal femora. Our data indicate that irradiation produces free radicals that adversely affect the survival of MSCs in both distal and proximal femora. Irradiation injury to the vasculatures and the microenvironment affect the niches for stem cells during the recovery period.  相似文献   
997.
目的 对国内建立的结核分枝杆菌DNA环介导恒温扩增(loop-mediated isothermal amplification, LAMP)快速检测方法进行了介绍和评价。 方法 实验菌株来源于北京结核病胸部肿瘤研究所。以结核分枝杆菌作为研究对象,设计了4 条LAMP 引物特异地识别结核分枝杆菌中 gyr B 基因的6个特殊区域。所有的菌株样本提取DNA作为模板,加入LAMP反应管后,65 ℃恒温反应60 min即可。其结果可以通过肉眼观察到的颜色变化来判断。 结果 实验共验证了79株临床和标准菌株。对于菌株的培养物,LAMP实验的灵敏度为100%,特异度为92%。 结论 结核分枝杆菌LAMP快速检测方法是一种快速、可靠的结核分枝杆菌诊断方法。  相似文献   
998.
Sildenafil, a phosphodiesterase-5 inhibitor, and simvastatin, a cholesterol lowering drug, both have therapeutic effects on PAH; however, the combination of these drugs has not been tested in the treatment of PAH. The purpose of this study was to determine whether the combination of sildenafil and simvastatin is superior to each drug alone in the prevention of MCT-induced PAH. Phosphorylated Smad levels were decreased in lung tissue in MCT-injected rats, whereas ERK protein levels were increased. This indicates a possible role for an increase in mitogenic ERK activity in addition to decreased proapoptotic Smad signaling in the MCT model of PAH. Combination sildenafil and simvastatin treatment prevented the MCT-induced increases in right ventricular systolic pressure (RVSP) and right ventricular hypertrophy (RVH), exerted an anti-proliferative effect on pulmonary artery smooth muscle cells (PASMC). Our results indicate that combination therapy with sildenafil and simvastatin attenuated the development of pulmonary hypertension more than either treatment alone.  相似文献   
999.
1000.
背景:肾移植后血管并发症采用介入治疗已成为一种安全有效的治疗方法。目的:探讨肾移植后血管并发症介入治疗的经验及价值评估。方法:回顾性分析8例肾移植后血管并发症患者介入治疗的临床资料。结果与结论:8例移植后5例肾移植肾动脉狭窄,2例假性动脉瘤,1例肾静脉血栓,均经彩色多普勒血流显像作出初步诊断,其中5例进一步行磁共振血管成像明确诊断。5例移植肾动脉狭窄行球囊扩张,分别随访6,8,20,36,40个月,1例出现再狭窄,随访血肌酐维持在130~160μmol/L之间,其余4例移植肾狭窄无复发,随访血肌酐均正常。2例假性动脉瘤患者经动脉鞘放入支架释放系统释放带膜支架后动脉瘤消失,目前常规血液透析治疗。1例肾静脉血栓形成患者,尿激酶介入溶栓治疗后血栓消失,患者发生移植肾功能延迟恢复,35d后血肌酐降至210μmol/L,此后患者血肌酐维持在200~250μmol/L。8例介入治疗临床效果说明肾移植后血管并发症治疗可选用介入治疗方法。  相似文献   
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