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41.
汕头卫生检疫局空港处对汕头航空口岸—宗入境二级货包的监测过程及对有关运输工作人员作了放射知识问卷调查。从中发现。运输单位货物存放设施落后。有关工作人员放射卫生知识欠缺,对放射污染可能造成的危害缺乏正确的认识。为此,笔者提出了自己的看法,以期对放射监测工作的进一步完善提供参考。  相似文献   
42.
The application of Doppler-tipped guide wires to measure blood flow velocity in coronary and peripheral arteries has been described previously as a valuable means of functional assessment in interventional cardiological procedures. In animal studies intravascular Doppler has been used in the cerebrovascular system, and this appears to be an important field of application for this new technique. We used intravascular haemodynamic monitoring by the Doppler guide wire during neuroendovascular procedures in patients with different cerebrovascular diseases and evaluated the clinical feasibility of the method. We found it a safe technique which complements morphological angiographic information with valuable functional data. Further studies may be expected to demonstrate the relation of flow parameters to clinical outcome. Received: 16 January 1996 Accepted: 30 January 1996  相似文献   
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44.
For certain genetic conditions DNA testing identifies carriers and determines the risk status of foetuses, thus helping parents to make more informed prenatal decisions. Data, collected from three genetic centres in England and Wales from August 1986 to July 1990, are used to describe trends in demand for DNA testing, the impact of DNA tests on carrier risk assessment, and the use of DNA tests in relation to pregnancy outcome. Altogether the data include 23,388 subjects and 681 pregnancies in 8738 families divided into five cohorts by year of entry and referral. The most frequent gene disorders referred to the genetic centres are currently being tested or will soon be tested. For these disorders the initial high level of activity has declined and may have reached steady state. Demand for DNA services is high for cystic fibrosis and Duchenne muscular dystrophy, intermediate for Huntington's disease, and low for adult polycystic kidney disease, phenylketonuria and tuberous sclerosis. Based on these findings we suggest that demand for DNA tests will be high in serious, untreatable and slow progressing conditions with early onset; intermediate for conditions affecting intellect and neurological integrity with later onset; and low for treatable, late-onset conditions, or those for which there is evidence of heterogeneity, and variable penetrance. It would be helpful to assess the extent to which this view of demand is confirmed when the new disorders being DNA tested are considered and for the pattern of activity of DNA testing for some types of cancer. Since no DNA centre could offer a fully comprehensive testing service, it is recommended that a structure is created to audit overall activity, assist in policy formulation, and influence supraregional service organisation, in order that the spread of DNA services be planned as effectively as possible. This structure would facilitate monitoring of the evolution of contract specifications agreed by commissioners and providers on a regional basis.  相似文献   
45.
Summary In order to investigate possible effects of smoking and drinking on the metabolism of toluence in occupational settings, 206 toluene-exposed men (mean age: 31.4 years) in shoemaking, painting, or surface-coating workshops together with 246 nonexposed control men (36.8 years) were studied for the time-weighted average intensities of exposure to toluene, hippuric acid concentration in shift-end urine samples, and the two social habits of smoking and drinking. The mean daily consumptions of cigarettes and ethanol were about 20 pieces and 10 g among smokers and drinkers, respectively. The geometric mean toluene concentration among the exposed subjects was about 20 ppm, with a maximum of 521 ppm. Regression analysis after classification of the subjects by smoking and drinking clearly demonstrated that the two social habits, when combined, markedly reduce the hippuric acid level in the urine of workers exposed to was a significant association between smoking and drinking habits, which hindered separate evaluation of the effects of the two habits on toluene metabolism. Comparison of the present results with the findings reported in the literature, however, suggested that the observed effects may be attributable to smoking rather than to drinking habits.  相似文献   
46.
脊髓手术中体感诱发电位监测的临床研究   总被引:3,自引:0,他引:3  
报告30例脊髓手术中体感诱发电位(SEP)连续监测的临床研究结果。SEP记录包括脊髓SEP(SSEP)和皮层SEP(SCEP)。麻醉药物对SEP有一定程度影响,SCEP相对较大。认为,至少术中SEP潜伏期延长不超过8%和波幅降低不超过50%,不会引起术后并发症,超过该范围由于病例较少,尚不能肯定与预后的关系,需进一步探讨。  相似文献   
47.
[目的 ]分析中药车前草中的无机盐成分 .[方法 ]利用正丁醇萃取、乙醇沉淀去杂质、聚酰胺柱层析及大孔吸附树脂柱层析等方法进行分离和提纯 .[结果 ]从车前草中分离得到 1种无机物 ,鉴定为氯化钾 .  相似文献   
48.
医院洁净手术室智能监控系统的设计与实现   总被引:1,自引:0,他引:1  
随着信息技术和自动化技术的发展,实现手术室的智能监控有助于提高工作效率和确保手术安全进行.本文简要介绍了"医院洁净手术室智能监控系统"的设计理念及其相关功能,给出了系统的硬件配置和软件实现.  相似文献   
49.
A recent series of randomized prospective clinical trials that compared rate control with rhythm control in patients with atrial fibrillation (AF) found no significant difference in primary outcome between the two strategies. However, these trials lacked clear criteria for defining "successful" rate or rhythm control. Various measures have been used to gauge the success of antiarrhythmic drug therapy, including time to first recurrence of AF, any AF recurrence, AF burden, and a reduction in symptoms. Determining the success of antiarrhythmic therapy can be relatively straightforward by using how patients feel during therapy as a key endpoint. Most patients are satisfied with a major reduction in symptomatic AF episodes and can live comfortably with occasional episodes of AF. For those who are bothered by even infrequent, brief AF episodes, a treatment regimen that eliminates nearly all AF recurrences is required, although often hard to achieve. Catheter ablation may be necessary to achieve a successful outcome in these patients. Suppression of AF in a patient at high risk of stroke does not, however, remove the need for concomitant warfarin therapy. The endpoints of ventricular rate control are not clear, and the recently published rhythm versus rate control trials lacked standard criteria for judging acceptable rate control. One relatively simple method is to try and achieve a 24-hour heart rate that mimics expected normal sinus rhythm. It is important to achieve good rate control to minimize symptoms and the risk of tachycardia-mediated cardiomyopathy.  相似文献   
50.
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