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81.
难治性气管异物的处理   总被引:1,自引:0,他引:1  
目的 探讨难治性气管异物的处理方法。方法 回顾 1994~ 2 0 0 3年 10年内收治的 12 5 8例气管异物中 ,10 9例难治性气管异物 (塑料笔帽、鸡骨头、图钉、钢珠、苍耳子球、玩具、带壳花生米、气门芯等 )的处理过程。患者年龄最小的为 8个月 ,最大的为 43岁。异物史最长达 12年。结果  89例难治性气管异物直接从支气管镜下取出 ,19例行气管切开 ,1例气门芯异物开胸取出。结论 在处理难治性气管异物时要做好充分的术前准备 ,正确判断和处理并发症。  相似文献   
82.
AIM: To evaluate the relationship between changes in serum transforming growth factor β1 (TGFβ1) level and curative effect of radiotherapy (RT) in patients with esophageal carcinoma.METHODS: Ninety patients with histologically confirmed esophageal carcinoma were enrolled. Serum samples for TGFβ1 analysis were obtained before and at the end of RT. An enzyme-linked immunosorbent assay was used to measure serum TGFβ1 level. Multivariate analysis was performed to investigate the relationship between disease status and changes in serum TGFβ1 level.RESULTS: Serum TGFβ1 level in patients with esophageal carcinoma before RT was significantly higher than that in healthy controls (P < 0.001). At the end of RT, serum TGFβ1 level was decreased in 67.82% (59/87) of the patients. The overall survival rate at 1,3 and 5 years was 48.28% (42/87), 19.54% (17/87)and 12.64% (11/87), respectively. Main causes of death were local failure and regional lymph node metastasis.In patients whose serum TGFβ1 level decreased after RT,the survival rate at 1, 3 and 5 years was 61.02% (36/59),28.81% (17/59) and 18.64% (11/59), respectively. The survival rate at 1 year was 17.86% (5/28) in patients whose serum TGFβ1 level increased after RT, and all died within 18 mo (P < 0.01).CONCLUSION: Serum TGFβ1 level may be a useful marker for monitoring disease status after RT in patients with esophageal carcinoma.  相似文献   
83.
本文用生物发光技术建立了定量测定绿脓杆菌(PA)对聚苯乙烯表面粘附的研究方法,同时观察了影响 PA 粘附的某些因素,比较了12株 PA 菌株对聚苯乙烯的粘附率。结果表明:在生物发光(BL)反应体系中,在萤虫素/萤虫素酶浓度给定的条件下,发光强度与 PA 释放的 ATP 量呈剂量依赖关系;在 PA 粘附体系中,其与聚苯乙烯表面的粘附随菌量的增加和粘附时间的延长而增加并受其缓冲液 pH 和菌龄的影响;不同 PA 菌株在同一条件下对聚苯乙烯的粘附率具有很大差别。  相似文献   
84.
2005~2006年江西省血吸虫病疫情监测点螺情调查结果分析   总被引:1,自引:0,他引:1  
目的分析2005~2006年江西省12个国家级血吸虫病疫情监测点螺情调查结果,掌握各监测点钉螺消长情况。方法依据《全国血吸虫病疫情监测点方案》,对各监测点钉螺孳生环境与可疑环境进行调查,比较两年的各项螺情指标。结果2006年12个监测点的有螺面积较2005年下降17.27%,但各监测点有螺面积下降幅度不相一致,有10个监测点查出有阳性钉螺分布;另外各监测点活螺密度、阳性螺密度也有较大波动。结论各监测点螺情依然严重,应加强控制钉螺的防治力度。  相似文献   
85.
心脾综合征的多普勒超声心动图诊断   总被引:1,自引:0,他引:1  
目的:探讨多普勒超声心动图对心脾综合征的诊断价值,分析其心脏伴随畸形漏诊及误诊原因,提高对心脾综合征诊断的准确率。方法:本文总结了221例心脾综合征患儿的超声检测结果,并与其心血管造影或磁共振检查结果进行对照。结果:超声心动图诊断为心脾综合征与心导管或磁共振结论符合者199例(占90.0%),诊断不符合者22例(占10.0%)。结论:多普勒超声心动图可以较准确地诊断心脾综合征,但对其心脏伴随畸形检出的准确率尚待进一步提高。  相似文献   
86.
87.
Transmural electrical dispersion determines the repolarization sequence across the ventricular wall, and plays an important role in the development of arrhythmias under pathological conditions. While it is clear that the transmural gradient of the transient outward current ( I to) underlies the dramatic difference in phase 1 repolarization across the ventricle, its contribution to the transmural action potential duration (APD) dispersion is not clear. We investigated this problem using the dynamic clamp technique in canine ventricular myocytes. The dynamic clamp allows quantitative 'insertion' of simulated conductances in real, biological cells, bridging pure computer modelling and experimental electrophysiology. 'Insertion' of an epicardial level of I to in endocardial cells produced a prominent phase 1 repolarization and a 'spike-and-dome' action potential morphology, but did not significantly affect the APD. Increasingly larger I to densities prolonged, and then dramatically shortened the endocardial APD. We also used the dynamic clamp to subtract, or 'block' the native I to in epicardial cells. Such 'blockade' eliminated the epicardial action potential notch, but had no significant effect on the APD. We conclude that I to, while being a key regulator of phase 1 repolarization, does not significantly affect the APD of canine ventricular myocytes, and that the I to gradient is not a significant contributor to the transmural APD dispersion in the canine ventricle. By allowing computer simulation on a biological background, the dynamic clamp is a new and effective tool to study the ionic basis of the electrical properties of cardiac cells.  相似文献   
88.
89.
Pesticide regulation is examined in the context of Health Canada’s Pest Management Regulatory Agency’s assessment of the chlorophenoxy herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) for turf. 2,4-D is the most common herbicide used to kill weeds in grass.The medical literature does not uniformly indicate harms from herbicides. However, the balance of epidemiological research suggests that 2,4-D can be persuasively linked to cancers, neurological impairment and reproductive problems. These may arise from 2,4-D itself, from breakdown products or dioxin contamination, or from a combination of chemicals.Regulators rely largely on toxicology, but experiments may not replicate exposures from 2,4-D application to lawns because environmental breakdown products (eg, 2,4-dichlorophenol) may not accumulate and selected herbicides are possibly less contaminated. Dioxins are bioaccumulative chemicals that may cause cancer, harm neurological development, impair reproduction, disrupt the endocrine system and alter immune function. No dioxin analyses were submitted to the Pest Management Regulatory Agency, and the principal contaminants of 2,4-D are not among the 17 congeners covered in pesticide regulation. Independent assessment of all dioxins is needed, in tissues and in the environment.The 2,4-D assessment does not approach standards for ethics, rigour or transparency in medical research. Canada needs a stronger regulator for pesticides. Potentially toxic chemicals should not be registered when more benign solutions exist, risks are not clearly quantifiable or potential risks outweigh benefits. Until landscaping pesticides are curtailed nationally, local bylaws and Quebec’s Pesticide Code are prudent measures to protect public health. Physicians have a role in public education regarding pesticides.  相似文献   
90.
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