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排序方式: 共有1170条查询结果,搜索用时 15 毫秒
1.
Virginia Hill Rice Thomas N. Templin Janet K. Harden Elizabeth S. Jenuwine Ibrahim Abdulhamid Adnan Hammad 《The Journal of adolescent health》2019,64(3):333-339
Purpose
The purpose of this study was to determine the prevalence of respiratory and/or physical fitness health problems in adolescent (ages 18–21) water pipe (WP) smokers (with or without cigarette smoking), cigarette-only smokers, and nonsmokers.Methods
A comparative four-group study design was used to recruit a non–probability sample of 153 WP smokers only, 103 cigarette smokers only, and 102 cigarette+WP smokers along with 296 nonsmokers. Our hypothesis was that youth who smoked WPs and/or cigarettes would report more respiratory problems and/or poorer physical fitness than those who did not smoke.Results
The results showed that coughs were significantly associated with smoking in all three of the smoking groups (p < .05). Cigarette-only smokers reported the most adverse outcomes with more wheezing, difficulty breathing, and less ability to exercise without shortness of breath. A dose-response analysis showed similar patterns of adverse health effects for both WP and cigarette smokers. The combined use of both products was not appreciably worse than smoking one product alone. This could be due to cigarette+WP smokers' reporting using less of the respective products when only one product was smoked.Conclusions
Even during the adolescent years, WP and/or cigarette smoking youth experienced reportable negative health effects. 相似文献2.
《Clinical lung cancer》2020,21(6):e551-e559
BackgroundMetformin is the first option in managing type 2 diabetes mellitus (DM) and has pleotropic effects. We studied the incidence of lung cancer in patients who received metformin therapy.Patients and MethodsThis study was retrospectively designed and based on the Korean National Health Insurance Service–National Health Screening Cohort to determine whether metformin reduces lung cancer risk in the diabetic population. At baseline, all participants were 40 to 69 years old and were categorized into 3 groups: metformin nonrecipients with DM, metformin recipients with DM, and the nondiabetic group.ResultsA total of 336,168 individuals were included in the final analysis (314,291 nondiabetic individuals, 8806 metformin recipients, and 13,071 metformin nonrecipients). The study median follow-up period was 12.86 years. The estimated cumulative lung cancer incidence of metformin nonrecipients, metformin recipients, and the nondiabetic group was 1.80%, 1.97%, and 1.24% in men and 1.87%, 0.61%, and 0.41% in women, respectively (P < .05). Compared to metformin nonrecipients, the hazard ratios (95% confidence intervals) for lung cancer incidence of metformin recipients and the nondiabetic group were 1.287 (0.979-1.691) and 0.835 (0.684-1.019) in men and 0.664 (0.374-1.177) and 0.553 (0.359-0.890) in women, respectively. The hazard ratios (95% confidence intervals) were statistically significant in male ever smokers (0.784 [0.627-0.979]) and female nonsmokers (0.498 [0.320-0.774]) after stratification according to smoking status.ConclusionMetformin therapy did not reduce lung cancer incidence in the diabetic population. However, individuals without DM were at a lower risk of lung cancer, especially in male ever smokers and female nonsmokers. 相似文献
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We provide evidence for the causal relationship between unemployment insurance (UI) and individuals’ smoking behavior using the 1995–2011 Current Population Survey-Tobacco Use Supplement data. Our identification relies on the exploitation of the exogenous variations of the maximum UI weekly benefits across states and over years. Instead of focusing on all unemployed people, we concentrate on those who are eligible for UI benefits. We find that when the maximum UI weekly benefit level increases by $100, smoking cessation increases by approximately 2.9 percentage points among the UI-eligible unemployed. The results are robust to various model specifications. We also explore the mechanism and find suggestive evidence that the increase in the maximum UI weekly benefit leads to a decrease in the probability of over-work of the respective spouse. Moreover, the unemployed who are less educated are more responsive to the increasing UI benefits. 相似文献
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Joint effect of glutathione S‐transferase genotypes and cigarette smoking on idiopathic male infertility 下载免费PDF全文
S. L. Yarosh E. V. Kokhtenko M. I. Churnosov M. A. Solodilova A. V. Polonikov 《Andrologia》2015,47(9):980-986
Inconsistent results of association studies investigated the role of glutathione S–transferase genes in idiopathic male infertility may be explained by ethnical differences in gene–gene and gene–environment interactions. In this study, we investigated a joint contribution of GSTM1, GSTT1 and GSTP1 gene polymorphisms and cigarette smoking to the risk of idiopathic infertility in Russian men. DNA samples from 203 infertile and 227 fertile men were genotyped by a multiplex polymerase chain reaction (GSTM1 and GSTT1 deletions) and PCR‐restriction fragment length polymorphism (GSTP1 I105V) methods. The GSTP1 genotype 105IV was associated with increased risk of male infertility (OR = 1.50 95% CI 1.02–2.20 P = 0.04). Genotype combinations GSTP1 105II/GSTT1 del (G1), GSTM1 del/GSTT1 del (G2) and GSTM1 + /GSTT1 del (G3) were associated with decreased risk of male infertility (P ≤ 0.003), whereas a genotype combination GSTP1 105IV/GSTT1 + (G4) was associated with increased disease risk (P = 0.001). The genotype combinations G3 and G4 showed a significant association with infertility in smokers; however, nonsmokers carriers did show the disease risk. In conclusion, GSTM1, GSTT1 and GSTP1 genes are collectively involved in the development of idiopathic male infertility and their phenotypic effects on the disease risk are potentiated by cigarette smoking. 相似文献
8.
OBJECTIVE: It has been suggested that oxidative stress plays a role in the pathogenesis of chronic obstructive pulmonary disease (COPD), though this role has yet to be fully elucidated. The purpose of this study was to further evaluate this role as concomitantly expressed in the saliva and broncho-alveolar lavage (BAL/'lavage'). DESIGN: Forty consenting patients (mean age 62+/-13-year-old), with/without COPD and/or smoking habit, participated in the study. The following antioxidant profile was examined both in saliva and lavage of the patients: total antioxidant status (TAS), uric acid (UA), peroxidase and super oxide dismutase (SOD). Total protein (TP) and albumin (Alb) were also evaluated in both saliva and lavage while amylase was measured only in saliva. RESULTS: Increase of TAS (by 100%) and of SOD activity levels (by 60%) in the lavage of COPD patients indicated oxidative stress. The salivary UA in COPD patients was 125% higher (p = 0.05) while the peroxidase was 20% higher. Another novel finding was that levels of salivary antioxidants in smoking versus non-smoking COPD patients were lower by 25-48% (for all four: TAS, UA, peroxidase and SOD) while the albumin was significantly reduced by 60% (p = 0.018). CONCLUSION: Oxidative-stress-related changes demonstrated both in the lavage and saliva of the COPD and/or smoking patient indicate cumulative effects of both, also emphasizing the pathogenetic role of free radicals in COPD. Salivary analysis, which is less invasive and much easier to perform as compared with lavage analysis, is suggested as a new and effective diagnostic tool in COPD patients. 相似文献
9.
《Archives of oral biology》2014,59(2):142-148
ObjectiveAldehydes and reactive nitrogen species (RNS) are important chemically active agents in cigarette smoke (CS). Salivary lactate dehydrogenase (LDH) originates predominantly from oral epithelium and was identified as an oral state marker. Its activity in saliva decreases after CS exposure. The aims of the current study were to identify the specific damaging agents in CS responsible for this activity reduction and to understand the mechanisms participating in CS oxidative damage to the salivary enzymes.MethodsPurified and salivary LDH samples were exposed to different levels of CS, pure acrolein, acetaldehyde, peroxynitrite and RNS donors. Each response of the isolated agent to the exposure was examined by a spectrophotometric enzyme activity assay and a Western blot.ResultsCS exposure caused a 34% reduction in LDH activity. Isolated treatment with unsaturated-aldehydes (acrolein, 10 μmol) caused a 61% reduction, while saturated-aldehydes (acetaldehyde, 200 μmol), peroxynitrite (200 μM) and RNS donor (SIN-1, 2 mM) caused no substantial effect. All five LDH isoenzymes reacted similarly. The carbonyl immunoblotting assay revealed a fourfold increase in carbonyl content when treated with CS and a sevenfold increase when treated with acrolein.Conclusionα,β-Unsaturated-aldehydes were identified as the main CS ingredient responsible for salivary LDH activity diminution. The effect of saturated-aldehydes and RNS donors was negligible. Unsaturated-aldehydes are capable of introducing carbonyl group into proteins, causing their dysfunction. This provides a molecular explanation for a decrease in LDH enzymatic activity in saliva. 相似文献
10.
目的:探讨香烟提取物(CSE)能否引起小鼠C2C12成肌细胞衰老,并研究成肌细胞衰老与组蛋白去乙酰化酶2(HDAC2)的关系。方法:培养C2C12细胞株,分化为成熟成肌细胞,观察CSE干预对成肌细胞衰老和HDAC2表达的影响,采用real-time PCR和Western blot方法分别检测HDAC2 mRNA和蛋白的表达;β-半乳糖苷酶染色检测衰老细胞的百分率。结果:MTT法测定最佳CSE浓度与干预时间分别为60 m L/L和24 h。CSE干预后β-半乳糖苷酶染色阳性细胞数增加,同时伴有HDAC2 mRNA和蛋白表达的减少。四溴苯三唑(TBB)在促进HDAC2 mRNA和蛋白表达的同时,β-半乳糖苷酶染色阳性细胞数减少;用HDAC2的特异性阻滞剂丙戊酸抑制HDAC2 mRNA和蛋白的表达时,β-半乳糖苷酶染色阳性细胞数增加。结论:香烟提取物可通过减少小鼠C2C12成肌细胞HDAC2的表达促进细胞老化。 相似文献