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31.
Three hundred and sixteen healthy Icelandic men and women were examined for the effect of the cholesteryl ester transfer protein (CETP) I405V polymorphism on plasma triglycerides, HDL cholesterol (HDLC) and apoAI concentration. Genotyping was performed using an allele specific oligomelting assay and the frequency of the V allele was 0.31 (95 CI for men 0.23–0.33 and for women 0.29–0.39). In women no significant difference was associated with the V405 genotype for any plasma lipid trait. However, men who were homozygous for the V405 allele had 9% higher apoAI and 14% higher HDLC levels (p < 0.05) than those homozygous for the common 1405 allele. The genotype effect was seen only in the non-smokers (p = 0.07 and <0.05, respectively), and in those consuming alcohol (p < 0.05 for both). Analysis of interaction between the environmental, life-style factors and genotype in men for the traits of HDLC and apoAI showed statistically significant interaction of the genotype only with alcohol consumption. The non-smoking men who reported alcohol consumption and who were homozygous for the CETP V405 allele had 16% higher plasma apoAI concentration than those who carried the 1405 allele, and up to 20% higher apoAI level than smokers. On the basis of prospective studies carried out on the Icelandic population, non-smoking, alcohol-consuming men who are homozygous for the V405 allele could have from 32% to 40% lower risk of having a heart attack. 相似文献
32.
R. Bendayan G. Kennedy R. C. Frecker E. M. Sellers 《European journal of clinical pharmacology》1993,44(1):51-55
Summary The efficacy of cimetidine as a treatment that could reduce smoking in heavily dependent smokers has been determined. In a randomised, double-blind, double-crossover experiment, 43 heavy smokers were divided into two groups, one receiving cimetidine 400 mg orally three times a day, and the other receiving placebo for two weeks followed by the alternative treatment (placebo or cimetidine).No significant difference in the mean alveolar carbon monoxide, nicotine or cotinine levels was found between the two treatment groups compared to baseline. Since the alveolar carbon monoxide level reflects the intensity of smoking behaviour, the results suggest that no change in smoking behaviour occurred in the subjects.Contrary to our previous findings that cimetidine decreased the total body clearance of nicotine by 30% in a population of non-smokers, in the heavily dependent smokers, cimetidine did not appear to alter nicotine elimination. One possible explanation for the discrepancy is that tobacco smoking is known to induce nicotine metabolism and the induction might have offset any effect of cimetidine on nicotine elimination.Cimetidine does not appear to be a useful treatment leading to a reduction or cessation of cigarette smoking. 相似文献
33.
Tibor P. Palfai 《Cognitive therapy and research》2002,26(3):317-333
This study examined the association between smoking outcome expectancy accessibility and smoking behavior. Daily smokers completed a smoking expectancy accessibility task in which they made timed judgments to a series of positive consequences of smoking either after 6 hr deprivation or within 10 min of smoking. Participants then completed a questionnaire battery that contained assessments of smoking behavior and smoking outcome expectancies. Results of hierarchical regression analyses showed that expectancy accessibility was associated with the number of cigarettes smoked per day even when controlling for corresponding questionnaire measures of smoking expectancies. Moreover, smoking expectancy accessibility predicted urge to smoke ratings following exposure to a smoking cue after controlling for the effects of deprivation. Findings suggest that smoking expectancy accessibility may play a central role in smoking behavior and that individual differences in this attribute may be assessed directly through reaction time assessment. 相似文献
34.
35.
香烟烟雾吸入对大鼠局灶性脑缺血后梗死灶的影响 总被引:1,自引:1,他引:0
目的 观察香烟烟雾吸入对大鼠局灶性脑缺血后梗死灶的影响,探讨其机制。方法 建立吸烟大鼠模型。用TTC染色法测定梗死灶体积,检测大鼠局灶性脑缺血后神经功能缺陷评分及梗死灶体积占同侧半球百分比。结果 除戒烟组外各吸烟组大鼠神经功能缺陷评分及梗死灶体积与对照组相比显著增加,吸烟4周、8周及12周依次增加。戒烟组神经功能评分及梗死体积明显低于吸烟4周组,与对照组无显著差别。结论 吸烟可加重大鼠局灶性脑缺血后脑组织损害,且随着吸烟时间增加而加重,戒烟可使这种脑损害得到一定程度的恢复。 相似文献
36.
Case-control study of silicosis, silica exposure, and lung cancer in white South African gold miners 总被引:3,自引:0,他引:3
A case-control study was undertaken to assess the association between lung cancer and silicosis or silica dust exposure in white South African gold miners. Cases and controls were identified from deaths reported to the Gold Miners Provident Fund for the period January, 1979-October, 1983. Two controls were matched to each case by year of birth (+/- 2 years) and by smoking (+/- 5 cigarettes or equivalents per day) assessed 10 years (+/- 2 years) prior to death. One hundred thirty-three matched triplets were identified. The results showed no overall association between lung cancer and radiological silicosis (OR = 1.08, p = 0.92). Autopsy data indicated no overall associations between lung cancer and silicosis of the lung parenchyma (OR = 1.49, p = 0.11), the pleura (OR = 0.72, p = 0.30), or the hilar glands (OR = 0.85, p = 0.72). A trend toward increased severity of silicosis of the parenchyma was evident; however, this was not statistically significant (p = 0.08). Odds ratios for lung cancer and silicosis were higher at lower levels of cumulative silica dust exposure (ORs = 2.43, 1.72, 1.35 and 0.62 for lung cancer and autopsy silicosis of the parenchyma for the lowest, second, third, and highest quartiles of dust exposure, respectively; all p greater than 0.05). Cases did not differ from controls for total silica dust exposure, length of exposure, weighted average intensity of exposure, or number of shifts at high dust (all p greater than 0.20). The data do not support the hypothesis of a carcinogenic role for silica dust and no statistically significant associations were found between lung cancer and silicosis.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
37.
38.
被动吸烟与婴幼儿呼吸系统疾病及生长发育关系的研究 总被引:3,自引:0,他引:3
张海英 《中国煤炭工业医学杂志》2003,6(5):405-406
目的 探讨被动吸烟对婴幼儿乎吸系统疾病发病及对生长发育的影响。方法 将我院保健科负责保健的0~3岁的婴幼儿400名,以家长是否吸烟分为被动吸烟组和对照组,每组200名,定期询问患病史,同时翻身高、体重对其进行评价,追踪观察,经统计学处理后进行分析。结果 婴幼儿乎吸系统疾病的发病与被动吸烟密切相关,被动吸烟影响婴幼儿的生长发育,与国内外的相关报道基本一致。结论 被动吸烟对婴幼儿健康速成严重损害,如不加以保护,有演变为严重社会问题的危险。 相似文献
39.
本文以1975-1984年为时段,对云南锡业公司所属六个单位工人进行了吸烟情况的调查分析。结果表明,吸烟者的肺癌发病率是非吸烟者的3.65倍。吸烟者的SMR为29.41;非吸烟者为8.42。无论吸烟程度如何,其发病、死亡都是有井下史者高于无井下史者。吸烟与职业性因素的复合作用是:吸烟+井下>单纯井下>单纯吸烟>非吸烟无井下史者。 相似文献
40.
Eight male habitual smokers smoked two cigarettes over a 20-min period following a 12-h period of abstinence. Antecubital venipuncture was performed immediately before, immediately after, and 55 min and 2 h after smoking had ceased. At these times, the mean values (+/- SD) of collagen-induced platelet aggregation were 45 +/- 5, 68 +/- 5, 59 +/- 6 and 52 +/- 5 chart units, respectively, while the corresponding values for the mean platelet aggregate ratio were 0.91 +/- 0.01, 0.82 +/- 0.03, 0.87 +/- 0.02 and 0.90 +/- 0.02, respectively. Mean collagen-induced platelet aggregation was significantly (P less than 0.005) higher immediately after, and 55 min and 2 h after smoking. The mean platelet aggregate ratio was significantly (P less than 0.001) lower immediately after and 55 min after smoking. Correlation coefficients between the concentration of nicotine in each of the 24 plasma samples obtained after smoking and the corresponding values of collagen-induced platelet aggregation and the platelet aggregate ratio were 0.41 (P less than 0.05) and -0.50 (P less than 0.02), respectively. It is concluded that when habitual smokers abstain from smoking overnight, a 20-min period of cigarette smoking may enhance platelet aggregability for as long as 2 h. 相似文献