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81.
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   
82.
Summary. In order to investigate fat metabolism and the regulation of lipolysis and blood fuel metabolites by insulin, nine patients with chronic obstructive pulmonary disease (COPD) with chronic hypoxaemia and seven healthy control subjects of similar age were investigated by determination of the turnover rate of free fatty acids (TOR), using 1-14C-oleic acid as a tracer, and arterial concentrations of FFA, glycerol and 3-hydroxybutyrate. The measurements were performed in the basal state and during insulin and glucose infusion, aiming at euglycaemia at insulin levels of 50 and 100 mU l-1. The subjects' ages were 64±2.7 and 66±1.1 (mean±SEM) years in the COPD and control groups, respectively. TOR was 0.73±0.06 and 0.52±0.02 mmol min-1 (P<0.05) in the basal state, 0.33±0.04 and 0.30±0.02 at an insulin level of 50 mU I-1 and 0.32±0.08 and 0.24±0.02 at an insulin level of 100 mU I-1, in the COPD and control groups, respectively. Arterial FFA concentration was 0.98±0.08 and 0.75±0.06 mmol 1-1 (P<0.05) in the basal state in the COPD and control groups, respectively. During the clamp, the decrease in FFA mirrored that in TOR. The results show that the state of lipolysis is increased in severe COPD patients with chronic hypoxaemia. Furthermore, the results suggest a reduced effect of insulin in lipolysis.  相似文献   
83.
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   
84.
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   
85.
目的:观察糖心乐(TXL)对糖尿病性心肌病(DCMP)大鼠血糖、血脂的影响。方法:SD大鼠随机分为正常对照组、模型对照组、达美康组及糖心乐大、小剂量组。将除正常对照组外的各组大鼠腹腔注射STZ建立糖尿病模型,造模后8w分别给予生理盐水、达美康、TXL大小剂量灌胃,连续4w,正常对照组不做处理。结果:与模型对照组比较,达美康组、糖心乐大、小剂量组大鼠的血糖、甘油三酯(TG)、总胆固醇(TC)显著降低(P<0.05,P<0.01),高密度脂蛋白(HDL-C)显著升高(P<0.05,P<0.01)。TXL大剂量组的降低血糖、TC,升高HDL-C作用与达美康组相当,降低TG作用优于达美康组(P<0.05)。结论:TXL可通过降低血糖、TG、TC水平,升高HDL-C水平来改善DCMP大鼠心肌的功能。  相似文献   
86.
[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   
87.
红景天苷对3T3-L1脂肪细胞糖代谢及细胞分化的影响   总被引:16,自引:0,他引:16  
目的:观察红景天苷对脂肪细胞糖代谢和细胞分化的影响,分析其改善糖代谢的可能机制.方法:检测红景天苷干预的脂肪细胞对 3H-葡萄糖的摄取,对红景天苷干预分化的细胞进行油红O染色后通过比色法分析脂肪细胞分化程度.逆转录多聚酶联反应(RT-PCR)检测脂肪细胞分化相关基因过氧化物体增殖剂活化受体-γ(PPAR-γ)、CAAT/增强子结合蛋白-α(C/EBP-α) mRNA的表达. 结果:红景天苷组葡萄糖摄取率为110.4%,明显高于正常对照组 (P<0.01);红景天苷明显抑制细胞分化及PPAR-γ、C/EBP-α mRNA表达,与对照组比较,P<0.01.结论:红景天苷促进3H-葡萄糖摄取,可抑制脂肪细胞分化,下调分化相关基因的表达.  相似文献   
88.
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   
89.
层流洁净手术室空气日常监测方法效果观察   总被引:2,自引:0,他引:2  
目的探讨层流洁净手术室空气日常监测有效方法。方法对层流洁净手术室百级、千级、万级各1间手术间,分别按《医药卫生洁净室(区)沉降菌的测试方法》GB/T16294-1996、《医药消毒卫生标准》GB/T15982-1995,在相同的温度、湿度下,共计8d,专人定时静态下,采用多点布控法(多点布控组)与常规布控法(常规布控组),分两组不同高度进行空气沉降法采样,30min后进行检测。结果多点布控与常规布控采样,细菌菌落数均未超标;无致病菌检出。多点布控组与常规布控组监测结果经t检验,有显著性差异(P<0.01)。多点布控采样效果优于常规布控组。手术区在0.8m、1.2m高度多点布控采样检测结果无细菌生长;周边区地面上采样与周边高度0.8m处采样监测结果经χ2检验,有显著性差异(P<0.05),多点布控周边区地面上采样阳性率高于周边高度0.8m采样。常规布控0.8m高度采样阳性率高于1.2m高度采样,采样监测结果经χ2检验,无显著性差异(P>0.05)。结论采用多点布控,手术区0.8 ̄1.2m高度、周边地面上采样进行空气沉降法监测是洁净手术室空气日常监测的有效方法。  相似文献   
90.
Many Australian Aboriginal bushfoods contain slowly digested carbohydrate which elicit low postprandial blood glucose and insulin responses compared to Western foods, such as wheat bread. This study has shown that incorporation of flour made from a slowly digested seed, Acacia coriacea , into wheat bread (18 g/82 g wheat flour) significantly reduces the initial rise in plasma glucose levels ( p < 0.05) and the area under the plasma glucose curve ( p < 0.005) in six healthy subjects. Insulin values were also lowered at 60 minutes ( p < 0.025) and 90 minutes ( p < 0.05). Our findings suggest that Acacia flour, when used to dilute wheat flour in the manufacture of breads, produces a very palatable food which could be useful in the diets of diabetic individuals.  相似文献   
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