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1.
Cigarette smokers have a wide variety of tar and nicotine yields to choose from in the current market, ranging from 0.5 mg tar and less than 0.05 mg nicotine to 27 mg tar and 1.8 mg nicotine by the Federal Trade Commission (FTC) method. To understand better the relationship between FTC nicotine yields and actual nicotine uptake in smokers, we have studied nicotine uptake in 33 smokers of self-selected products representing four tar groupings: 1 mg tar (1 MG), ultra-low tar (ULT), full-flavor low tar (FFLT), and full flavor (FF) cigarettes. These cigarette categories had mean FTC nicotine yields of 0.14, 0.49, 0.67, and 1.13 mg/cigarette, respectively. The subjects smoked their usual brand of cigarette ad libitum and provided a 24-h urine sample for total nicotine uptake analysis over a period during which the number of cigarettes smoked was recorded. Nicotine uptake was determined by monitoring urinary nicotine and its metabolites, including the glucuronide conjugates. Daily nicotine uptake was 9.1±7.3 mg (range 1–21 mg) for 1 MG, 19.2±10.0 mg (range 4–42 mg) for ULT, 21.8±9.4 mg (range 13–38 mg) for FFLT, and 37.1±14.4 mg (range 21–60 mg) for FF smokers. On a per cigarette basis, yields were 0.23±0.11, 0.56±0.23, 0.60±0.18, and 1.19±0.43 mg nicotine, respectively. Although individual variability was fairly large (CVs of 0.39–0.80), means for the different groups showed that lower FTC yield smokers not only absorb less nicotine per 24-h period, but also per cigarette smoked. These data suggest that nicotine uptake is a function of individual smoking behavior within product design limits. We conclude from these data that, while FTC yield cannot precisely predict nicotine uptake for an individual smoker, it is useful in predicting and comparing actual nicotine uptake by smokers who select cigarettes with a particular FTC yield.  相似文献   
2.
为评价部分平均通过时间(MTTp)和F-V曲线形状对检查吸烟者小气道功能的临床意义,作者对116例被动和轻、重度主动吸烟者进行了常规肺通气功能、MTTp和F-V曲线形状的探讨。常规肺通气功能和F-V曲线形状用常规法测定。MTTp用“简易计算法”公式计算。结果显示凸型F-V曲线的分布随吸烟程度而上升。·V50、·V25下降及MTT45%~55%、MTT70%~80%延长在凸型与重度吸烟组一致。MTT45%~55%与MTT70%~80%延长的范围在两者都是预计值的110%~120%,表明小气道功能已有轻度障碍。因而凸型F-V曲线、MTT45%~55%及MTT70%~80%延长、·V50、·V25下降都是检查小气道功能的敏感指标。用“简易计算法”计算MTTp简便准确,宜于临床推广应用  相似文献   
3.
Background:Plasma fibrinogen is considered a biomarker of respiratory disease, owing to the relationship between plasma fibrinogen and pulmonary function established in Western populations. However, such a relationship has not yet been confirmed in an Asian population. We assessed this relationship in the general Japanese population.Methods:Totally, 3,257 men and women aged ≥40 years who participated in a community-based annual health checkup in Takahata, Japan, from 2004 to 2006, underwent spirometry, and their plasma fibrinogen levels were determined.Results:We found an inverse relationship between spirometric measures (percent predicted forced vital capacity [%FVC] and forced expiratory volume in 1s [%FEV1], and FEV1/FVC) and plasma fibrinogen levels in men, but not in women. The plasma fibrinogen levels were significantly higher in subjects with restrictive, obstructive, and mixed ventilatory disorders than in those with normal spirometry results. Multiple linear regression analysis revealed that in men, plasma fibrinogen levels were predictive for %FVC and %FEV1 (independent of age, body mass index, and cigarette smoking) but not for FEV1/FVC.Conclusions:Plasma fibrinogen was significantly associated with pulmonary function in Japanese men, and as such, plasma fibrinogen might be a potent biomarker for pulmonary dysfunction in men.  相似文献   
4.
目的 应用高分辨超声技术对原发性高血压及高血压伴吸烟患者的内皮依赖性血管舒张功能进行研究和分析。方法 采用高频超声技术 ,对 6 3例患者其中 2 2例原发性高血压 (EH) ,2 2例高血压伴吸烟患者(EH+SM) ,和 19例正常血压无吸烟史者 (NT)的血管内皮依赖性舒张功能进行测定评价 ,并测定其血浆一氧化氮 (NO) ,内皮素 (ET) ,血栓素 B2 (TXB2 )和前列腺环素 (PGI2 )等血管活性物质的浓度变化。结果 发现 EH+SM和 EH组肱动脉血流介导的血管舒张百分率 FMD%均较 NT组明显减弱 (P均 <0 .0 0 1) ,EH+SM组又较EH组明显减弱 (P=0 .0 2 3) ,而三组对硝酸甘油的反应无显著性差异 (P均 >0 .0 5 )。 EH+SM及 EH组血浆 NO,PGI2 水平均较 NT组减低 (P均 <0 .0 1) ,EH+SM组又较 EH组明显降低 (P=0 .0 2 9)。结论 高血压患者存在血管内皮依赖性舒张功能受损 ,高血压伴吸烟患者 ,内皮功能损伤进一步加重 ,高频超声是评价血管内皮依赖性舒张功能的简单、无创、可靠的方法。  相似文献   
5.

Objective

This study examined the prevalence of smoking, the rates of transitions, and predictors of transition through the three stages of smoking.

Methods

A total of 1785 high school students in Tabriz (northwest of Iran) were assessed at 2 time points with a 12-month interval in 2005 and 2006, regarding changes in smoking stages. The predictor variables were measured when the students were in the 10th grade. Logistic regression was employed to predict the different smoking stages at grade 11.

Results

The results showed that 14.3% (95% confidence interval, 12.3%-16.4%) and 2.8% (2.0%-4.0%) of the never smokers became experimenters and regular smokers, respectively, whereas 16.5% (12.4%-21.7%) of the experimenters became regular smokers. Among never smokers, participation in groups with at least one smoker (odds ratio, 1.24 (95% confidence interval, 1.05-1.47)), having smoker friends (1.85 (1.21-2.83)), and a positive attitude toward smoking (1.22 (1.02-1.46)) predicted smoking experience. Among the experimenters, those who had general risk behaviors (2.56 (1.12-5.87)) and participated in groups with at least one smoker (2.58 (1.26-5.31)) significantly progressed to becoming a regular smoker at the follow-up.

Conclusion

Prevention of smoking in adolescence should begin by focusing on the predictors of transition through smoking stages, especially participating in smoker groups.  相似文献   
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8.
106例吸烟健康老年人胸部X线分析   总被引:1,自引:1,他引:0  
本文对200名健康男性老年人的胸部X线片进行了测量分析。其中包括94名不吸烟和106名吸烟者。测量结果:吸烟组的肺长度(L)、肺宽度(W)的均值随吸烟而增高。右膈弓高(BD)随吸烟而下降。且吸烟量与肺长度(L)呈正相关,与右膈弓高(BD)呈负相关。结果表明:长期大量吸烟会导致肺体积增大,其中以肺长度(L)的增加和右膈弓高(BD)的减少最为明显。  相似文献   
9.
Rationale  Dependent smokers exhibit deficits in attentional and memory processes when smoking abstinent as compared to when satiated. While nicotine replacement therapy improves attention during abstinence, it is unclear whether this is due to the alleviation of withdrawal-related deficits or inherent beneficial effects of nicotine. Objectives  The primary aim of these studies was to test whether nicotine exerts a beneficial effect on novelty detection and whether such effects occur in nonsmokers as well as habitual smokers. Materials and methods  In two parallel, double-blind, placebo-controlled studies, 24 smokers (study 1) and 24 nonsmokers (study 2) were tested in two counterbalanced sessions: once while wearing a nicotine patch (smokers = 14 mg; nonsmokers = 7 mg) and once while wearing a placebo patch. On each day, participants performed three content-specific oddball tasks (perceptual, semantic, and emotional) that required them to press a button whenever they saw a novel target (20% of stimuli) embedded in a stream of common nontarget stimuli (80% of stimuli). Recognition memory for targets was subsequently tested. Reports of mood, smoking withdrawal, patch side effects, and blind success were collected in each session. Results  Among smokers, compared to placebo, nicotine decreased target reaction time during all oddball tasks. Among nonsmokers, nicotine increased target detection accuracy and subsequent memory recognition. Nicotine’s enhancement on each respective measure was not task-content specific in either sample. Conclusions  These data suggest that acute nicotine administration may exert direct beneficial effects on novelty detection and subsequent memory recognition in both smokers and nonsmokers. Moreover, these effects are not content-specific.  相似文献   
10.
BACKGROUND: The aim of this study was to assess the relationship between exposure to cadmium and bladder cancer risk. METHODS: We conducted a case-control study in Belgium and measured the blood levels of cadmium in 172 bladder cases and 359 population controls. The data were analyzed as tertiles after logarithmic transformation. Cut-off points were based on the levels among the controls. Logistic regression was performed to calculate odds ratios (ORs) for bladder cancer occurrence with corresponding 95% confidence intervals (95% CI). RESULTS: After adjustment for sex, age, and occupational exposure to PAHs or aromatic amines, the OR for cadmium was 8.3 (95% CI 5.0-13.8) comparing the highest to the lowest tertile (p for trend <0.001). Additional adjustment for smoking (current cigarette smoking status, years of cigarette smoking and number of cigarettes smoked per day) decreased the OR, however it remained strongly significant (OR: 5.7; 95% CI 3.3-9.9). CONCLUSION: Our study suggests that individuals with increased exposure to cadmium have an increased risk of bladder cancer. Future studies should expand on this investigation by studying a larger number of bladder cancer patients and by collecting extensive information on the lifetime occupational, residential, and environmental exposures to clarify the role of cadmium in bladder cancer.  相似文献   
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