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31.
目的:选用人脐静脉内皮EA.hy926细胞株作为研究对象,观察二甲基亚砜溶解的香烟尘粒(DSP)对人脐静脉内皮EA.hy926细胞生长的影响。方法:以(1、2、4、8)mL/L剂量DSP作量效实验,小剂量DSP(2mL/L)作时效实验,采用MTT比色法和96孔板细胞蛋白测定方法来评价DSP对该细胞株增殖和活性的影响。透射电镜(TEM)观察不同处理因素作用后细胞超微结构变化。结果:DSP能抑制人脐静脉内皮EA.hy926细胞增殖(P<0.05),且对该细胞株具有明显毒性,它能减少细胞蛋白合成(P<0.05)、增加细胞死亡(主要为坏死),作用呈剂量和时间依赖。结论:DSP能损伤血管内皮细胞(VEC)。 相似文献
32.
Seventy-seven smoker clinic clients who managed at least 2 weeks of smoking abstinence while chewing 2 mg nicotine gum reported the degree to which the gum reduced their craving for cigarettes, their daily gum consumption and the extent of urges to smoke despite the gum. Greatest relief from craving by the gum was reported by smokers with higher pre-abstinence expired-air carbon monoxide (CO) concentrations and higher stimulant and dependent scores on a smoking motivation questionaire but not greater usual daily cigarette consumption. Gum consumption correlated positively with expired-air CO, usual daily cigarette consumption, and stimulant and dependent smoking scores. Despite the gum, urges to smoke and difficulty not smoking were reported and the severity of these was associated with indulgent, stimulant and dependent smoking scores but not CO or usual daily cigarette consumption. The results are discussed in terms of the possible role of pharmacological and non-pharmacological factors in craving. 相似文献
33.
Twenty-two volunteers who smoked more than 20 cigarettes with "high" nicotine yields (0.8 to 1.2 mg) per day participated in an 8-week study designed to test the hypothesis that smoking cigarettes with a constant level of nicotine but reduced deliveries of tar, carbon monoxide, and hydrogen cyanide leads to a decrease in smoke absorption. All subjects smoked their usual high-nicotine brand for the first 3 weeks (P1), and the absorption of smoke constituents was determined from levels of thiocyanate and cotinine in saliva and serum, levels of carbon monoxide in expired air, and levels of carboxyhemoglobin in the blood. During the final 5 weeks (P2), the treatment group (16 subjects) switched to the "light" version of their usual brands (similar yields of nicotine but with reduced yields of tar, carbon monoxide, and hydrogen cyanide); the control group (6 subjects) smoked their usual brands for the duration of the study. Average levels of cotinine for the subjects who switched during P2 were not significantly different from those of the control group as was expected. Slight reductions were noted in average expired-air carbon monoxide levels, blood carboxyhemoglobin, and saliva thiocyanate, but these reductions were smaller than anticipated based on brand characteristics. The results suggest that the ratio of smoke constituents is different when individuals, rather than machines, smoke cigarettes. Yields determined under subject-defined conditions are necessary in order to properly evaluate the role of nicotine in the design of "less-hazardous" cigarettes. 相似文献
34.
《Health & place》2021
We estimated the discriminatory power of area of residence (census tract) on the prevalence of main risk factors for chronic diseases. Results, based on a sample of 21,007 participants from the 2011–2012 National Health Survey of Spain, show a differential influence of the geosocial environment on the four health risk factors. Accounting for census tracts substantially increases the discriminatory power regarding at-risk alcohol consumption, unbalanced diet, and leisure-time sedentarism but not tobacco consumption. However, the socioeconomic characteristics of the tracts played a minor role. Further research on the specific geosocial contextual variables explaining variability in these risk factors is necessary. 相似文献
35.
目的探讨石家庄市居民慢性阻塞性肺疾病检出情况及影响因素。方法2021年9—12月采用整群随机抽样方法抽取石家庄市3个社区,对抽中社区的所有居民进行问卷调查和肺功能检查。利用描述流行病学方法分析社区人群慢性阻塞性肺疾病患病现状。应用单、多因素方法分析影响慢性阻塞性肺疾病发生的危险因素。结果共2348名居民完成问卷调查和肺功能检查,其中男1205人,占51.32%,女1143人,占48.68%,年龄31~76岁。共有146例检出慢性阻塞性肺疾病,检出率为6.22%,其中轻度69例,占47.26%,中度54例,占36.99%,重度23例,占15.75%,未检出极重度者。检出来的症状分布中,以咳嗽及咳痰的比例较高,分别为52.05%(76例)和49.32%(72例)。多因素Logistic回归分析结果显示年龄≥40岁(OR=1.705、1.936)、男性(OR=3.404)、居住在农村(OR=2.469)、偶尔或经常吸烟(OR=1.592、1.800)、有职业粉尘接触史(OR=2.179)、有哮喘家族史(OR=3.164)、有慢性阻塞性肺疾病家族史(OR=5.170)、有呼吸道反复感染史(OR=3.414)是石家庄市居民慢性阻塞性肺病患病的影响因素。结论石家庄市居民的慢性阻塞性肺疾病患病情况不容乐观,且危险因素众多。重点针对中老年、吸烟、农村、有各种相关家族史的男性高危人群开展早期筛查和采取针对性干预措施,有助于对居民慢性阻塞性肺疾病进行防控。 相似文献
36.
目的:调查农村居民吸烟情况及其危险因素。方法:通过整群抽样方法调查了12696名15岁以上农村居民的吸烟情况,同时收集其他相关信息。利用SAS软件包对这些资料进行卡方检验及logistic回归等分析。结果:观察烟者占3.12%,男性现吸烟率(61.68%)明显高于女性(3.37%)人群总戒烟率为11.78%,其中因“患病”而戒烟者占72.14%,经Loistic回归分析,发现性别、年龄、低文化程度、婚史、家庭成员有吸烟者均为吸烟行为的影响因素,结论:那些离异、文化程度低、年龄小于45岁的男性为吸烟行为的高危人群。 相似文献
37.
目的为了研究吸烟对健康人体的危害.方法采用观测人体甲襞微循环的方法,检测了急、慢性吸烟对微循环的影响.结果吸烟组受试者的甲襞微循环的管袢形态、血液流态、管周状态和总积分值均有异常改变,与对照组比较有显著差异(P<0.01).结论提示吸烟可造成组织缺氧、血粘度增高,引起机体微循环明显障碍. 相似文献
38.
吸烟与女性乳腺癌关系的Meta分析 总被引:4,自引:0,他引:4
目的 探讨吸烟与乳腺癌关系。方法 采用Meta分析的方法,对我国学 者在公开发表的8篇有关吸烟与乳腺癌关系的病例对照研究文献进行综合定量分析。根据资料一致性检验,采用随机效应模型(D-L法)计算合并比值法(OR)及其95%的可信区间(95%CI)。结果 吸烟与乳腺癌之间总的合并OR为1.56,其中95%CI1.09-2.24,按主动吸烟和被动吸烟与乳腺癌关系合并的OR值及95%CI分别为1.67(0.45-6.22)和1.65(1.10-2.30),但主动吸烟与乳腺癌的联系无统计学意义(P>0.05)。结论 吸烟是乳腺癌的危险因素。 相似文献
39.
兴义地区97例健康吸烟者的血流变学及甲襞微循环的变化 总被引:2,自引:0,他引:2
目的 探讨不同烟龄、吸烟量的吸烟者的血流变学及甲襞微循环的变化及意义。方法 随机选择97例不同烟龄、吸烟量的吸烟者,年龄23-52岁,不吸烟者37例,年龄21-54岁,均为健康体检者。进行全血粘度、血浆比粘度、红细胞压积(HCT)及甲襞微循环的各项积分值(形态、流态、袢周状态、总积分)的统计分析。结果 不同烟龄、吸烟量的吸烟者在全血粘度、血浆比粘度及甲襞微循环的各项积分值与不吸烟者有显著性差异(P<0.05或P<0.01)。结论 吸烟者的血流变学及甲襞微循环有显著性改变,尤其是通过甲襞微循环表现得更为突出。 相似文献
40.
BackgroundNon-union is a significant complication of fracture fixation surgery, and can negatively impact a patient’s quality of life. Low intensity pulsed ultrasound (LIPUS) has been used to treat delayed or non-unions previously in the literature. The aim of this study was to determine the success rate of LIPUS treatment in patients with chronic fracture non-unions, and to establish the effect of systemic or local factors on its success.MethodsThis was a retrospective, observational study which included all patients undergoing LIPUS treatment in a single institution. Patients deemed suitable for LIPUS underwent treatment for a period of 6 months from initiation. They were followed up with sequential radiographs to assess union at intervals of 6 weeks, 3 months, 6 months and 1 year. LIPUS treatment was considered to be successful when patients achieved clinical and radiological union, without the need for revision surgery.ResultsA total of 46 patients were included in the study; 8 were lost to follow – up, leaving 38 patients for the final analysis. The mean age of patients was 47.03 ± 19.7 with a male to female ratio of 1.2:1. Union was achieved in 57.89%; the rest underwent revision surgery. There was no significant association between outcomes after LIPUS treatment and patients’ age, gender, smoking status or type of non-union. Patients with a small inter-fragment bone gap were more likely to have a successful outcome after LIPUS (p = 0.041). Time to treatment did not have a statistically significant impact on outcomes after LIPUS. Interestingly, all 6 patients with diabetes in the study managed to achieve union after LIPUS.ConclusionsThis study demonstrates that LIPUS is not successful in a large proportion of patients with established fracture non-unions. However, it does represent a low risk treatment modality as an alternative to revision surgery, especially for patients with diabetes who have a small inter – fragment bone gap. More research in the form of large randomised controlled trials needs to be carried out to further assess the role of LIPUS in the treatment of non-unions. 相似文献