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21.
目的 比较他汀类药物和阿司匹林联合用药与单用阿司匹林对急性冠脉综合征患者血脂、高敏C反应蛋白及纤维蛋白原的影响。方法 所有患者均在急性冠脉综合征发病后72h内开始接受药物治疗,他汀组(40例)应用他汀类药物加阿司匹林治疗8周,对照组(16例)单用阿司匹林治疗,观察两组总胆固醇、低密度脂蛋白胆固醇、高敏C反应蛋白和纤维蛋白原水平的变化。结果 治疗8周后,他汀组各指标显著降低,面对照组仅高敏C反应蛋白水平显著下降。他汀类药物降低高敏C反应蛋白、纤维蛋白原的程度与其降脂作用无关。结论 他汀类药物与阿司匹林联合用药降低高敏C反应蛋白和纤维蛋白原的作用可能优于单用阿司匹林,并与其抗炎作用有关。  相似文献   
22.
During an exposure monitoring study, 78 saw maintenance tradesmen were randomly assigned to be interviewed about their exposures using one of two questionnaire formats: open-ended and partly prompted questions about five categories of materials; and detailed prompting about 75 agents. The more open-ended questionnaire elicited fewer exposure responses overall, but more responses about agents not included on the detailed questionnaire. Composite materials and trade name products were more frequently cited as exposures than individual metals or compounds. Validity of responses was ascertained using air measurements (individual metals) or observations of the employees (composite materials). Sums of sensitivities and specificities were very low (near 1.0) for most of the metals for both types of questionnaire. For composite materials, validity improved substantially. Sensitivities with the partly prompted format (0.44–0.85) were always lower than with detailed prompting (0.80–1.00). Specificities were usually, but not always, higher with partial prompting (0.66–0.92) than with detailed prompting (0.18–0.86). Selection of questionnaire format for an epidemiologic study would depend on the likely prevalence of exposure in controls and the effects of trade-offs in sensitivity and specificity.  相似文献   
23.
Coeliac disease has been associated with a variety of neurological conditions, most frequently cerebellar ataxia and peripheral neuropathy. To date, chorea has not been associated with coeliac disease. We present the case histories of 4 individuals with coeliac disease and chorea (4 women, average age of onset of chorea 61 years). Unexpectedly, most of these patients showed a notable improvement in their motor symptoms after the introduction of a gluten-free diet.  相似文献   
24.
A diurnal rhythm of sensitivity to exogenous melatonin was defined in adult male Turkish hamsters, Mesocricetus brandti. Melatonin was administered daily by subcutaneous injections (15 micrograms in 0.1 ml 10% ethanolic saline) for 10 weeks in animals exposed to 16 L:8 D. As in golden and Djungarian hamsters, two periods of melatonin sensitivity were identified. The first, in late afternoon, persisted for 6 hr, from 7 hr to 1 hr before lights off. The second period was briefer, of only 2 hr duration in the late night, terminating at the time of lights on. Melatonin injections given during these sensitive periods promoted testicular regression in most animals; melatonin administered at other times of the day was without effect on testicular function in most animals of these groups. Gonadal regression induced by properly timed melatonin injections was rapid, in many groups nearly complete in 6 to 7 weeks. The results are discussed in relation to the function of pineal melatonin in photoperiodic time measurement in hamsters.  相似文献   
25.
目的探讨3H-TdR掺入法在进行SMMC-7721系细胞肿瘤药敏试验实验时的最佳实验条件.方法确定出3H-TdR掺入法药敏实验时的最适细胞浓度、最适实验药物浓度、3H-TdR掺入最适时间;在最适条件下采用3H-TdR掺入法测定肝癌SMMC-7721细胞株对临床常用的9种抗癌药物的敏感性.结果应用3H-TdR掺入法检测肝癌SMMC-7721细胞株药敏试验的最适实验细胞浓度为1×104个/孔,最适试验药物浓度为1×PPC,3H-TdR最适掺入时间为收集细胞前8 h;肝癌SMMC-7721细胞株对DDP、ADM、5-FU、CPT高度敏感,对MTX、VP-16、MMC、NVB低度敏感,对PYM不敏感.结论 3H-TdR掺入法可用于肿瘤药物敏感性测定并确定出它的最适实验条件.  相似文献   
26.
Patch testing was carried out in 851 atopic patients; 181 atopic dermatitis (AD) patients were additionally tested with 50% dilutions of the test substances. The occurrence of allergic and irritant reactions was frequent, being 57% and 33% for AD patients aged 28-41 years and 19-27 years, respectively. Among age-matched allergic rhinitis (AR)/allergic conjunctivitis (AC) or asthma (A) patients, the number of allergic reactions varied from 25 to 30%, and for irritant reactions was 24%. In all groups, nickel, fragrance-mix, balsam of Peru and neomycin were the commonest allergens. Contact allergy to ingredients of topical medicaments was common among AD patients and patients with severe and long-lasting dermatitis were most frequently sensitized. However, sensitivity to multiple substances was not common among those patients. The number of irritant reactions was considerable, but 50% dilution of the test substances did not solve the problem.  相似文献   
27.
血清瘦素水平的影响因素及相关性分析   总被引:7,自引:3,他引:4  
目的探讨血清瘦素水平的影响因素及相关性分析.方法从2003年3~8月门诊体验人群中随机抽取标本150人,并排除糖尿病及高血压,测定FBS、血脂水平、血清瘦素水平(LEP)、胰岛素水平(INS),瘦素、胰岛素测定均采用放射免疫方法.胰岛素敏感性以敏感指数(IAI)评价.结果血清瘦素水平女性明显高于男性;相关分析显示血清瘦素水平与性别(SEX)、年龄(AGE)、体重指数(BMI)、INS显著正相关(r分别为0.429,0.329,0.249,0.322,P<0.05);与LOGIAI显著负相关(r=0.322,P<0.05),与TC,TG无明显相关;在调整年龄、BMI后,多远逐步回归分析显示血清瘦素水平仍与INS,LOGIAI显著相关.结论血清瘦素水平与TC,TG均无相关,提示高脂血症患者血清瘦素水平与正常人群比较无明显改变;血清瘦素水平与LOGIAI负相关,高瘦素水平人群胰岛素敏感性降低、存在胰岛素抵抗,提示瘦素-胰岛素轴的存在,瘦素是胰岛素抵抗的一个独立危险因素.肥胖患者存在高瘦素血症、瘦素抵抗.如果能弄清瘦素、胰岛素抵抗、肥胖之间的相互作用关系及因果关系,可能对瘦素抵抗、胰岛素抵抗相关痰病的防治有一定的意义.  相似文献   
28.
A more sensitive or higher concentration of rabbit brain thromboplastin does not result in greater accuracy and precision of results in oral anticoagulant therapy and is unable to mimic the PIVKA sensitivity of human brain. In terms of International Normalized Ratios the British Comparative Thromboplastin and Manchester Comparative Reagent (both now discontinued) and the Manchester Reagent had the poorest sensitivity to factor VII of all the reagents studied. It is not possible accurately to calibrate rabbit brain against human brain thromboplastin in the upper therapeutic range and beyond.  相似文献   
29.
The glucose clamp technique is currently regarded as the standard test for measuring insulin sensitivity against which other methods are compared but is unsuitable for routine screening of patients outside a hospital base. There is thus a need for a simpler test to measure insulin sensitivity. We have therefore compared the glucose disappearance rate KITT in the first 15 min of the insulin tolerance test (ITT) with the M and M/I values derived from the standard euglycaemic clamp in nine normal subjects and eight subjects with Type 2 (non-insulin dependent) diabetes mellitus and coexisting obesity. All subjects underwent the ITT and euglycaemic clamp in random order. Nine subjects later had a repeat ITT to determine the reproducibility of the test. In the ITT, 0.1 U kg-1 body weight, human Actrapid insulin was given as an IV bolus and simultaneous arterialized and venous blood samples were obtained every minute for 15 min. The first order rate constant for the disappearance of glucose KITT over the period 3-15 min was taken as a measure of insulin sensitivity. The euglycaemic clamp was performed with an insulin infusion of 50 mU kg-1 h-1 for 120 min and a variable rate glucose infusion to maintain blood glucose concentration at 0.5 mmol l-1 below fasting level to minimize the effect of endogenous insulin secretion. The ratio of the mean rate of glucose infused (M, mumol kg-1 min-1) to the plasma insulin over the last 30 min of the clamp was taken as a measure of tissue sensitivity to insulin (M/I) assuming endogenous glucose output was suppressed.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
30.
Colour discrimination and visual contrast perception were investigated in 18 patients with Huntington's disease (HD) and in 18 age- and sex-matched healthy volunteers using the Farnsworth-Munsell 100 Hue test (FM) and stationary contrast targets. The mean total error score (MTES) and the partial scores for the “red-green” and the “blue-yellow” axes in the FM of the patients with HD were significantly elevated as compared to controls (MTES in HD: 113.0 ± 90.8; MTES in controls: 19.2 ± 8.8). The spatial contrast sensitivity in HD patients was normal. The colour perception dysfunction indicates that the visual system is affected in HD. The visual disorder may be related to an imbalance of certain neurotransmitters in the visual system of HD patients. Possible anatomical sites of the dysfunction responsible for colour discrimination abnormalities could be the retinal cone system and/or impaired parvocellular central visual pathways in HD.  相似文献   
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