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41.
Acoustic rhinometry is one method to evaluate nasal geometry by an acoustic reflection technique. The aim of this study was to investigate the changes in acoustic rhinometry after nasal provocation in patients with exclusively perennial allergic rhinitis. In 19 patients, acoustic rhinometry and active anterior rhinomanometry were performed before and after nasal provocation test. There was a statistically significant nasal flow reduction measured by active anterior rhinomanometry after nasal provocation (p < 0.05) and a median symptom score of four points, both indicating a positive response to nasal provocation. On the other hand, there was no statistically significant change in the values of acoustic rhinometry after nasal provocation (p > 0.05). In patients with exclusively perennial allergic rhinitis, acoustic rhinometry does not seem to significantly change after nasal provocation. In contrast, active anterior rhinomanometry values decreased significantly after nasal provocation. The presented results indicate that acoustic rhinometry does not seem to be a diagnostic method superior to active anterior rhinomanometry in this context.  相似文献   
42.
While there is a burgeoning body of research linking smoking during pregnancy to problem behaviour in offspring, a major criticism of this work has been the crude measurement of exposure in these studies (e.g. retrospective, self-reported only) that could lead to biased estimates. To address this issue, we used a pregnancy cohort with repeated prospective measures of exposure as well as biological assays to generate estimates of exposure patterns using a range of modelling techniques. In this paper we report on the analytical approaches we have developed, including patterns of exposure over time and best-estimate approaches that combine self-report and cotinine measures, and compare their predictive value in relation to different dimensions of fetal growth as a first step towards examining the utility of greater precision of exposure measurement.
Surprisingly, in this sample the more complex assessments of exposure, including biological measures, generally did not perform better than simple indicators of exposure based on repeated self-report measures, with one exception: a combined self-report cotinine 'best estimate' of third trimester exposure was uniquely associated with lower brain : body ratio. Further study is needed using more sophisticated cotinine assays and testing prediction of a range of outcomes to ascertain whether these findings represent true differences or are specific to the sample, methods and outcomes used. Such research will inform the development of guidelines for adequate exposure characterisation in developmental studies.  相似文献   
43.
目的 观察初诊高血压病患者心理、个性和行为特征对控烟效果的影响.方法 对84例初诊高血压病吸烟患者行控烟治疗,连续3个月后评价控烟效果,并采用A型行为问卷、艾森克个性问卷(EPQ)及症状自评量表(SCL-90)对其进行测评.结果 控烟效果佳者38例,占45.24%;控烟效果差者46例,占54.76%.前者A型行为问卷、EPQ问卷(除外内外向性维度)评分均显著优于后者(P<0.05,P<0.01);SCL-90除偏执、阴性项目外,其余项目评分均显著优于后者(P<0.05,P<0.01).结论 A型行为类型、神经质和精神病性人格特征及负性情绪是影响控烟效果的重要因素,对此类患者实施控烟的同时予以针对性心理干预可望获得事半功倍的效果.  相似文献   
44.
Smoking delays the healing process and increases morbidity associated with many common musculoskeletal disorders, including long bone fracture. In the current study, a murine model of tibial fracture healing was used to test the hypothesis that smoking delays chondrogenesis after fracture. Mice were divided into two groups, a nonsmoking control group and a group exposed to cigarette smoke for 1 month prior to surgical tibial fracture. Mice were euthanized at 7, 14, and 28 days after surgery. The outcomes measured were immunohistochemical staining for type II collagen protein expression as a marker of cartilage matrix and proliferating cell nuclear antigen (PCNA) staining to measure proliferation at the site of injury. Toluidine blue staining and histomorphometry were used to quantify areas of cartilaginous and noncartilaginous fracture callus. Radiographs were analyzed for evidence of remodeling after injury. At day 7 after injury, mice exposed to cigarette smoke had a smaller fracture callus with less cartilage matrix compared to controls. Proliferation was present at high levels in both groups at this time point, but proliferating cells had a more immature morphology in the smoking group. At day 14, chondrogenesis was more active in smokers compared to controls, while a higher percentage of bone was present in the control animals. At day 28, X-ray analysis revealed a larger fracture callus remaining in the smoking animals. Together, these findings show that the chondrogenic phase of tibial fracture healing is delayed by smoking. This study represents, to our knowledge, the first analysis of molecular and cellular mechanisms of healing in a smoking mouse fracture model.  相似文献   
45.
同济医科大学控烟活动及效果评价   总被引:1,自引:0,他引:1  
我校自1993年开展控烟工作,1995年9月开始创办无吸烟大学校园,采取了卫生宣教和行政干预等综合措施,并进行了效果评价。高强度干预措施实施前期(1995年3月)和中期(1996年10月)相比,男医学生和男女学生平均吸烟率分别从16.3%和11.4%下降到9.6%和5.94%;男教工和男女教工平均吸烟率分别从28.6%和13.8%下降到13.9%和8.86%。  相似文献   
46.
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   
47.
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   
48.
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   
49.
目的 探讨主动吸入药物烟对大鼠NO的影响。方法 制备大鼠主动吸烟模型 ,采用硝酸还原酶法测定各组大鼠血清、肺、心肌及脑组织的NO含量。结果 非药物烟组大鼠血清、肺、心肌及脑组织中NO含量明显低于非给烟对照组 ,药物烟高、中剂量组NO含量明显高于非药物烟组 ,接近非给烟对照组。结论 吸烟对大鼠血液、肺、心肌及脑组织有不同程度的损伤作用 ,使NO含量降低 ;药物烟具有一定的保护和防止NO含量降低的作用。  相似文献   
50.
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   
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