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41.
The Adelaide Diagnostic Learning Inventory (ADLIMS) is a measure of learning styles and learning pathologies that was designed to investigate the impact of traditional approaches to learning versus problem-based learning and to identify students whose approach to learning tasks predicted poor academic performance. In this study, some important psychometric properties of the ADLIMS were examined, including its factor structure. In this study, factor replicability across samples was argued to provide a more robust and psychologically meaningful factor solution than that which can be obtained using traditional mathematical criteria. The results of the factor analysis did not confirm the presence of the four factor solution earlier reported for the ADLIMS, but did identify three clear factors that had very high replicability. An inspection of the items comprising these three factors showed that factor 1 tapped subjective distress related to poor study habits, lack of motivation to study, and distraction from social activities. Factor 2 tapped distress arising from high achievement expectations that were hampered by superficial or disorganized study habits that did not enable the student to grasp the relationships between concepts and ideas. Factor 3 tapped positive feelings and a sense of satisfaction associated with a problem-based approach to the learning of new study material. Although the internal reliability of the ADLIMS subscales met the requirements of a measure to be used in general research such as in the investigation of correlates among groups of medical students, they did not meet the higher requirements of a measure to be used to identify or predict individuals with pathological learning styles.  相似文献   
42.
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   
43.
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   
44.
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   
45.
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   
46.
Background: Mice immunized with murine mammary carcinoma cells genetically engineered to secrete interleukin-2 (IL-2) are rendered resistant to subsequent challenge with unmodified tumor cells, and in the case of mice bearing established tumors, the rate of development of pulmonary metastases is reduced. Despite these encouraging animal results, little is known about the induction of antitumor immunity by IL-2 gene transfer in human breast cancer. Methods: Adenovirally mediated IL-2 gene transfer was performed in 12 tumor fragment cultures established from seven primary breast cancers. Autologous tumor infiltrating lymphocytes (TILs) or peripheral blood mononuclear cells (PBMCs) were cocultured with transduced tumor fragments, and changes in phenotype and cytotoxicity were measured. Results: IL-2 was never detectable in the untransduced cultures, but it peaked at 5.0—1,324.8 ng/ml in the transduced cultures. Lymphocyte counts declined in all untransduced cultures, but they increased two- to sevenfold in four transduced cultures. CD4:CD8 ratios decreased from a mean of 2.11 at baseline to 1.27 after stimulation in coculture (p=0.03). Expansion of lymphocytes expressing the natural killer cell phenotype (CD3CD56+) occurred in only one culture, but the CD3+CD56+ population increased in four of six cultures. Lymphocytes from four of 10 cocultures generated significant cytotoxicity against allogeneic breast cancer cells. Induction of cytotoxicity correlated with expansion of the CD3+CD56+ phenotype (R2=0.805, p=0.02). Conclusions: IL-2 gene expression by human breast cancer causes expansion of CD3+CD56+ cytotoxic lymphocytes. This phenotype is consistent with that of a non-major histocompatibility complex (MHC)-restricted cytokine induced killer cell population previously described. Opinions, interpretations, conclusions and recommendations are those of the author and are not necessarily endorsed by the U.S. Army. Presented at the 49th Annual Cancer Symposium of The Society of Surgical Oncology, Atlanta, Georgia, March 21–24, 1996.  相似文献   
47.
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   
48.
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   
49.
8~12岁单纯性肥胖儿童心功能研究   总被引:4,自引:0,他引:4  
利用多导生理仪,同步记录心电图、心音图、颈动脉搏动图和心阻抗微分图,测试8~12岁肥胖儿童94名,对照组儿童76名,分析比较有关心功能数据。结果显示肥胖儿童收缩压、舒张压、平均动脉压、左室射血时间和心搏出量高于对照组儿童,心输出量与对照组比较差异无显著性,心功能指数低于对照组儿童。提示肥胖儿童由于回心血量增加,血压增高,而使心脏前、后负荷加重,心肌收缩力代偿性增强,单位体表面积心输出量下降,部分心功能指标已受到影响。  相似文献   
50.
①目的 观察适量饮酒对健康成年男性的血小板聚集功能及血浆血栓素B2 (TXB2 ) ,6 酮 前列腺素F2a(6 Keto PGF2a)的影响。②方法 将 80例健康成年男性随机分成 4组 ,分别空腹饮用矿泉水、啤酒、干红葡萄酒各 2 0 0mL ,白酒 50mL加矿泉水至 2 0 0mL .于饮前及饮后 2h分别测定血小板的聚集率及解聚率 ,并采血测定血浆TXB2 ,6 Keto PGF2a.③结果 矿泉水组饮后上述指标无变化 (t=0 .0 3~ 0 .84,P >0 .0 5) ;白酒、啤酒、红葡萄酒组饮后血小板聚集率减低 (t=8.1 2~ 2 4 .39,P <0 .0 1 ) ,解聚率升高 (t=2 8.48~ 35 .2 2 ,P <0 .0 1 ) ,血浆TXB2 降低 (t=2 5 .69~ 89.83 ,P <0 .0 1 ) ,而血浆 6 Keto PGF2a升高 (t=2 1 .0 6~ 2 3 .2 9,P <0 .0 1 )。④结论 健康成年男性适量饮酒可减低其血小板聚集功能 ,降低其血浆TXB2 ,提高其血浆 6 Keto PGF2a水平  相似文献   
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