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61.
Summary Among 701 Copenhagen plumbers we examined the lung function of 23 never smokers, who had removed asbestos insulation and intermittently been exposed to high levels of asbestos for about 25 years without being exposed to welding fume. The plumbers had significantly lower TLC, MEF25, MEF50, closing volume and closing capacity in comparison to 23 never smoking electricians without asbestos exposure. There was no reduction in TLCO. Pulmonary clearance of aerosolized 99mTc-DTPA was normal indicating that the asbestos had not induced increases in pulmonary epithelial permeability. However, in 11 of the 23 plumbers the 99m-Tc-DTPA ventilation scintigrams had a slightly irregular and spotty appearance, which together with the results of the lung function tests are suggestive of small airways' dysfunction. None of the subjects had symptoms or clinical signs of lung disease.  相似文献   
62.
Several areas related to the use of telescopes in low vision are reviewed. These include: contrast sensitivity function; eccentric viewing through a telescope; field of view; telescope used in reverse; and IOL-spectacle lens telescopic systems. Experimental data are included to support selected clinical observations routinely made by low vision clinicians.  相似文献   
63.
本研究主要对El Tor型霍乱弧菌(Vibrio cholerae biotvpe eltor,EVC)L型的某些生物学特性如生化反应、抗生素敏感性及超微结构等进行了探讨.研究发现EVC不稳定L型的生化性状与EVC流行株的非常相似,而稳定L型则变化很大.抗生素敏感性试验显示EVC稳定L型对某些作用于细胞壁的抗生素的敏感性减弱,而对大多数作用于蛋白质合成的抗生素的敏感性增强.与流行株相比,EVC稳定L型和不稳定L型的超微结构的改变很明显.此外,本文还讨论了产生这些改变的可能机制.  相似文献   
64.
目的 比较他汀类药物和阿司匹林联合用药与单用阿司匹林对急性冠脉综合征患者血脂、高敏C反应蛋白及纤维蛋白原的影响。方法 所有患者均在急性冠脉综合征发病后72h内开始接受药物治疗,他汀组(40例)应用他汀类药物加阿司匹林治疗8周,对照组(16例)单用阿司匹林治疗,观察两组总胆固醇、低密度脂蛋白胆固醇、高敏C反应蛋白和纤维蛋白原水平的变化。结果 治疗8周后,他汀组各指标显著降低,面对照组仅高敏C反应蛋白水平显著下降。他汀类药物降低高敏C反应蛋白、纤维蛋白原的程度与其降脂作用无关。结论 他汀类药物与阿司匹林联合用药降低高敏C反应蛋白和纤维蛋白原的作用可能优于单用阿司匹林,并与其抗炎作用有关。  相似文献   
65.
氨基酸负荷对梗阻肾的肾功能和肾储备功能的影响   总被引:1,自引:0,他引:1  
为寻求预测梗阻肾肾功能的新方法,用氨基酸负荷(AL)对25例双肾积水患者进行肾储备功能测定,并对负荷前后肾小球滤过率(GFR)、有效肾血浆流量(ERPF)、肌酐清除率(Ccr)、滤过分数(FF)、GFR百分比上升率(%GFR)进行比较性研究,以求预测肾功能恢复的客观指标。结果表明:AL能提高GFR、ERPF值,通过Ccr对比研究,进一步表明GFR增值能反映肾储备功能的变化,增值越高恢复越快,反之亦然。结果认为:肾储备功能的测定可预测肾功能恢复情况,并对肾积水疾病的手术方式选择有一定的指导作用  相似文献   
66.
Forty patients agreed to participate in a study to compare whether fentanyl or alfentanil used as analgesic is associated with quicker recovery following anaesthesia for outpatient arthroscopy procedure. Psychomotor tests including choice reaction time (CRT), perceptive accuracy test (PAT) and finger tapping test (FTT) were done prior to induction of anaesthesia with propofol (2–3 mg–kg-1). Patients were then divided into two groups: Group F (fentanyl) received 0.1 mg fentanyl prior to start of surgery and thereafter 0.05 mg every 30 min during the procedure. Group A (alfentanil) received 0.5 mg alfentanil prior to the onset of surgery and 0.25 mg every 15 min thereafter. Anaesthesia was then maintained using isoflurane (0.5–2%) in oxygen and air (Fio2 0.33) during spontaneous respiration with a face mask in a Bain's system. Psychomotor tests were repeated every 45 min postoperatively. Clinical recovery, visual analogue pain intensity score (VAS) and time to discharge home were also assessed by a nurse blind to the method used. Patients in Group A returned to baseline values on the FTT after 90 min while those in Group F did not return to baseline values until 135 min after the end of the operation. Clinical recovery and time to discharge home ("home ready") were also significantly longer in Group F. There was no difference in recovery as seen in the PAT and CRT between the groups. Also, there was no difference in the incidence of side effects and the pain intensity (VAS) scores were similar in the two groups at all time periods. We conclude that recovery following alfentanil is quicker compared to fentanyl when anaesthesia is based on isoflurane.  相似文献   
67.
比较69例冠心病患者多巴酚丁胺负荷99mTc甲氧基异丁基异腈(MIBI)心肌断层显像与82例运动试验99mTcMIBI心肌断层显像的结果,以探讨它们对冠心病的诊断价值。结果表明:以冠状动脉造影结果为标准,多巴酚丁胺负荷诊断冠心病的敏感性和特异性分别为912%和800%,运动试验分别为894%和829%。多巴酚丁胺负荷检出冠状动脉病变的敏感性和特异性:左前降支为781%和913%,回旋支为667%和982%,右冠状动脉为100%和837%;运动试验分别为783%和911%,600%和968%,909%和850%,差异均无显著性(P>005)。提示两者结果相近,对于不能进行运动试验的病人,多巴酚丁胺试验是一种有价值的诊断冠心病的方法。  相似文献   
68.
The pre-operative risk of paediatric liver transplantation candidates (n=41) was assessed in a prospective study by means of clinical symptoms, conventional static and liver blood flow dependent dynamic liver function tests. Nine patients died during the 365-day waiting period. The data were subjected as covariates to a survival analysis in the Cox proportional hazards model. There was a significant relationsship between the results of mono-ethylglycinexylidide (MEGX) formation and ICG test and the 365-day survival rate. In the stepwise analysis, none of the remaining parameters improved the predictive ability when added to the dynamic liver function test results. The assessment of post-transplantation liver function was studied in 27 patients during the first 28 postoperative-day period. In addition, liver function was studied in a cross-sectional study 1–7 years after successful liver transplantation in children with complete or partial rehabilitation. In the early postoperative period severe organ damage was indicated by both static and dynamic liver function tests. In the later course after transplantation no deterioration of liver function measured with MEGX formation was to be observed. These findings demonstrate the usefulness of dynamic liver function tests in the pre- and post-transplant assessment of liver function.  相似文献   
69.
人大肠癌细胞体外常温及温热环境中药物敏感性试验   总被引:1,自引:0,他引:1  
用MTT比色法对20例大肠癌患者术后标本在常温及温热环境中进行体外药物敏感性试验,结果显示,某些药物在温热环境中,对癌细胞的杀伤作用有显著提高,此项试验为临床温热化疗法提供了理论依据。  相似文献   
70.
Summary. To investigate the ability of various lung-function tests to demonstrate dilatation of peripheral airways, ten asthmatics inhaled increasing doses of a f2-agonist by two different and controlled techniques. Low inspiratory flow with a long post-inspi-ratory pause favoured peripheral deposition, and a high inspiratory flow with a short post-inspiratory pause favoured central deposition of drug in the airways. Ordinary spirometry, maximum expiratory flow rates after breathing air as well as a helium-oxygen mixture, a single breath N2-test and resistance of the respiratory system were obtained before and after each of five terbutaline doses with both inhalation techniques. By using a double-dummy technique, the study could be performed double blinded. Effects were compared at doses giving equal effects on PEF, assumed to represent equal deposition of bronchodilator and effects on central airways. At such ‘iso A PEF doses’, particularly FVC and the slope of phase III of the N2-test improved more following the slow inhalation technique. It is concluded that changes in those tests reflect dilatation in peripheral airways in asthmatics.,  相似文献   
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