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81.
1. Airways derived from different levels of the lung exhibit a difference in the reactivity and sensitivity to agonists. We have evaluated the effect of acetylcholine and cholinergic selective (pirenzepine, gallamine and 4-dipherylacetoxymethyl piperidine [4-DAMP]) and non-selective (atropine) antagonists on bovine proximal and distal smooth muscle preparations. 2. The distal preparations are more sensitive to acetylcholine than proximal bronchi. The relaxant effect of three selective antagonists on the distal and proximal tissues was the same when the results for each drug were compared. 3. Atropine and 4-DAMP were more potent than pirenzepine and gallamine in relaxing both proximal and distal bovine smooth muscle preparations. 4. These data suggest that the muscarinic sites on the smooth muscle of bovine airways are of the M3 subtype.  相似文献   
82.
Cardiac malignant mesenchymoma is an extremely rare malignancy with poor prognosis. We report a patient presenting with a history and clinical findings typical of mitral stenosis. Transthoracic echocardiography showed a mass on the thickened posterior mitral leaflet. Transoesophageal echocardiography revealed two tumoural masses: one on the atrial side of the posterior mitral leaflet causing mitral obstruction, the other arising in the region of the right lower pulmonary vein orifice and obstructing inflow through this vein.  相似文献   
83.
本文综述本校传染病学教研室1955~1995年间所取得的科研成果。内容包括10余种传染病与寄生虫病的临床和基础研究,其中以华支睾吸虫病、恙虫病等有广东特色的传染病以及伤寒、痢疾、病毒性肝炎等影响人民健康最普遍的传染病为重点。反映了建国以来各个时期本教研室对防治这些传染病所作的贡献。所取得的成果,相当一部分通过多年来的验证,已获得广大传染病工作者所认同或列为常规,部分已获得部委级奖励。现在重温这些成果,可能起承前启后的意义。  相似文献   
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OBJECTIVES: We sought to compare the prognostic value of pharmacological stress echocardiography (SE) in diabetic and nondiabetic patients with known or suspected coronary artery disease. BACKGROUND: Although SE is a useful tool for risk stratification of patients with diabetes, it has not been established whether it retains the same prognostic information in diabetic patients compared with nondiabetic patients. METHODS: A total of 5,456 patients (749 diabetics) undergoing dipyridamole (n = 3,306) or dobutamine (n = 2,150) SE were prospectively followed up for the occurrence of hard events (death and/or nonfatal myocardial infarction). RESULTS: During a median time of 31 months, 411 deaths and 236 infarctions occurred. There were 132 events in diabetic patients and 515 in nondiabetic patients (18% vs. 11%, respectively; p < 0.0001). Moreover, 1,607 (29%) patients underwent coronary revascularization and were censored. Ischemia at SE, resting wall motion score index, and age were independent predictors of death and hard events in both diabetic and nondiabetic patients. Compared with a normal test, ischemia and scar test patterns were associated to significantly lower age-corrected five-year hard event-free survival in diabetic as well as nondiabetic patients. However, a normal test was associated with a greater than two-fold annual event rate in diabetic patients as compared with nondiabetics who were either younger (2.6% vs. 1.0%) or older (5.5% vs. 2.2%) than 65 years of age. CONCLUSIONS: Stress echocardiography is equally effective in risk stratifying diabetic and nondiabetic patients independently of age. However, the normal test result predicts a less favorable outcome in diabetic than in nondiabetic patients.  相似文献   
87.
OBJECTIVE: To evaluate the efficacy and risks of autologous 'blood patch' pleurodesis in patients with persistent air leak after pulmonary resection. METHODS: All patients operated on by a single surgeon between January 2002 and January 2004 and presenting with a persistent air leak after pulmonary resection have been treated by the autologous blood patch pleurodesis technique. Fifty millilitres of autologous blood were injected through the chest tube that was then rinsed, clamped for 30 min and then unclamped and placed back to water seal. RESULTS: We have obtained a 100% success rate in 11 patients with persistent air leak who have been treated with this technique over a 2-year period. Most air leaks (72.7%) ceased within 12 h of blood injection. No patient developed empyema, but two patients developed fever and pleural fluid grew Staphylococcus after blood pleurodesis. At 3-month follow-up, all patients were well and their lungs were expanded fully. CONCLUSIONS: In our experience a single injection of 50 ml of blood is sufficient to seal persistent air leaks in less than 48 h. Although highly effective, the autologous blood patch pleurodesis technique should not be used in patients with incomplete lung re-expansion or positive pleural fluid culture to minimize the risk of empyema.  相似文献   
88.
BACKGROUND: Advanced glycation end products (AGEs) have biological properties that may contribute to the premature cardiovascular mortality of haemodialysis patients. This study examines the hypothesis that low molecular weight forms of fluorescent AGEs (LMW fluorescence) predict mortality in haemodialysis patients. METHODS: The LMW fluorescence was measured in 85 patients treated with chronic haemodialysis and prospectively followed for 4 years. The primary outcome of all-cause mortality was assessed using Cox proportional hazards regression model. RESULTS: At the end of the follow-up period 37 (44%) patients died. The median LMW fluorescence level was 24.2 arbitrary units (range: 10.6-148.1 AU) and the receiver operator characteristic (ROC) curve cut-off for mortality was 37.0 AU. The LMW fluorescence predicted death both as a binary variable at the ROC cut-off, and as a continuous log-transformed variable when adjusted for age, albumin and C-reactive protein (CRP). Adjusted for age, albumin and CRP, the hazard ratio for mortality was 3.05 (1.41-6.60, P = 0.005) for LMW fluorescence as a binary variable and 2.71 per log unit (1.37-5.38, P = 0.004) as a continuous log-transformed variable. CONCLUSION: The low molecular weight forms of AGEs predict mortality in patients receiving chronic haemodialysis, and may be important in the mechanisms leading to atherosclerosis and inflammation in such patients.  相似文献   
89.
BACKGROUND: The use of knee ankle foot orthoses (KAFOs) to prolong independent mobility is a widely used rehabilitation strategy for children with Duchenne muscular dystrophy (DMD). AIMS: To explore views and adjustment of families with a child with Duchenne muscular dystrophy to the use of KAFOs. METHODS: interviews with families of children aged 8-18 years with DMD; questionnaires on psychiatric adjustment (SDQ for children; GHQ for parents). RESULTS: In total, 17 parents and 9 children took part. Families experienced the introduction of KAFOs as a signal for illness deterioration and a re-awakening of the feelings experienced at diagnosis. Nevertheless, the majority expressed a positive attitude and over two-thirds satisfaction with KAFOs use. High psychiatric risk was found in 2/17 children (12%; expected 10%) and 7/17 main carers (41%; expected 20-30%). CONCLUSION: Most families were satisfied with KAFOs use, and its implementation was well tolerated especially by the children. However, mental distress was high in main carers who emphasized the importance of full preparation and support in this rehabilitation technique.  相似文献   
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