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排序方式: 共有2289条查询结果,搜索用时 15 毫秒
101.
Leah C. Stevenson India Bohanna Jan A. Robertson Alan R. Clough 《Drug and alcohol review》2013,32(6):627-630
102.
In this study 10 commercial top selling cigarette brands in Spain have been machine smoked and the mainstream smoke has been analyzed. Multifunctional analysis has been satisfactorily employed to correlate the effect of the main design features of the cigarettes including amount of tobacco, filter size or paper weight with the amount of smoked tobacco and with the ratio CO2/CO. The composition of the vapor phase and that of the particulate matter have been analyzed. The particulate matter retained in the filter of the cigarettes has also been analyzed showing a distinct behavior of the compounds condensed in the cigarette filters and in the traps, related to their retention time. A general trend for the relative yield of some compounds in the different brands have been identified and confirmed by multifunctional analysis. Nevertheless, there are some noticeable compounds that behave differently in the different brands. 相似文献
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Gen‐Huan Yang Yan‐Chuan Li Zhan‐Qi Wang Bao Liu Wei Ye Leng Ni Rong Zeng Shi‐Ying Miao Lin‐Fang Wang Chang‐Wei Liu 《Journal of pineal research》2014,57(4):451-458
Vascular restenosis after the interventional angioplasty remains the main obstacle to a favorable long‐term patency. Many researches suggest cigarette smoking is one of the most important causes of restenosis. This study was designed to investigate whether melatonin could protect against the cigarette smoke‐induced restenosis in rat carotid arteries after balloon injury. Three groups of male rats (normal condition, cigarette smoke exposed, cigarette smoke exposed, and melatonin injected) were used in this study. An established balloon‐induced carotid artery injury was performed, and the carotid arteries were harvested from these three groups 14 days later. The ratio of intima to media, the infiltration of inflammatory cells, the expression of inflammatory cytokines (NF‐κB, IL‐1β, IL‐6, TNF‐α, MCP‐1), adhesion molecules (ICAM‐1, VCAM‐1), and eNOS were measured. The results showed that cigarette smoke exposure aggravated the stenosis of the lumen, promoted the infiltration of inflammatory cells and induced the expression of the inflammatory cytokines and adhesion molecules after the balloon‐induced carotid artery injury. Moreover, cigarette smoke exposure can inhibit the expression of eNOS. Particularly, we surprised that melatonin could minimize this effect caused by cigarette smoke. These results suggested that melatonin could prevent the cigarette smoke‐induced restenosis in rat carotid arteries after balloon injury and the mechanism of its protective effect may be the inhibition of the inflammatory reaction. This also implies melatonin has the potential therapeutic applicability in prevention of restenosis after the vascular angioplasty in smokers. 相似文献
106.
《Toxicology mechanisms and methods》2013,23(4):320-333
AbstractTotal particulate matter (TPM) and the gas–vapor phase (GVP) of mainstream smoke from the Reference Cigarette 3R4F were assayed in the cytokinesis-block in vitro micronucleus (MN) assay and the in vitro chromosome aberration (CA) assay, both using V79-4 Chinese hamster lung fibroblasts exposed for up to 24?h. The Metafer image analysis platform was adapted resulting in a fully automated evaluation system of the MN assay for the detection, identification and reporting of cells with micronuclei together with the determination of the cytokinesis-block proliferation index (CBPI) to quantify the treatment-related cytotoxicity. In the CA assay, the same platform was used to identify, map and retrieve metaphases for a subsequent CA evaluation by a trained evaluator. In both the assays, TPM and GVP provoked a significant genotoxic effect: up to 6-fold more micronucleated target cells than in the negative control and up to 10-fold increases in aberrant metaphases. Data variability was lower in the automated version of the MN assay than in the non-automated. It can be estimated that two test substances that differ in their genotoxicity by approximately 30% can statistically be distinguished in the automated MN and CA assays. Time savings, based on man hours, due to the automation were approximately 70% in the MN and 25% in the CA assays. The turn-around time of the evaluation phase could be shortened by 35 and 50%, respectively. Although only cigarette smoke-derived test material has been applied, the technical improvements should be of value for other test substances. 相似文献
107.
Background. The reason for the substantial geographic variation in the prevalence of childhood asthma is not known. Objective. To investigate the association between exposure to cigarette smoking in the home and childhood asthma at the state-level, toward improving current understanding of geographic variation in childhood asthma rates. Methods. Data were drawn from the National Children's Health Survey (NCHS, 2003), a representative sample (n = 102, 000) of youth 0 to 17 years of age in the United States. Household smoking and asthma in children were reported by parents. Air quality for each state was obtained from Environmental Protection Act (EPA) reports, and state-level poverty reports were obtained from the US Department of Agriculture. Results. Household smoking was associated with a statistically significant increase in risk of asthma among children at the state level (p = 0.026). This association did not appear to be influenced by outdoor air quality at the state level or socioeconomic position. Conclusions. These results are the first to show a link between cigarette smoking in the home and childhood asthma at a state-level in the United States. 相似文献
108.
Objective: The effects of low-level environmental tobacco smoke (ETS) exposure, on asthma control, lung function and inflammatory biomarkers in children with asthma have not been well studied. The objective of the study was to assess ETS exposure in school-age children with asthma whose parents either deny smoking or only smoke outside the home, and to assess the impact of low-level ETS exposure on asthma control, spirometry and inflammatory biomarkers. Methods: Forty patients age 8–18 years with well-controlled, mild-to-moderate persistent asthma treated with either inhaled corticosteroids (ICS) or montelukast were enrolled. Subjects completed an age-appropriate Asthma Control Test and a smoke exposure questionnaire, and exhaled nitric oxide (FeNO), spirometry, urinary cotinine and leukotriene E4 (LTE4) were measured. ETS-exposed and unexposed groups were compared. Results: Only one parent reported smoking in the home, yet 28 (70%) subjects had urinary cotinine levels ≥1?ng/ml, suggesting ETS exposure. Seven subjects (18%) had FeNO levels >25parts per billion, six of whom were in the ETS-exposed group. In the ICS-treated subjects, but not in the montelukast-treated subjects, ETS exposure was associated with higher urinary LTE4, p?=?0.04, but had no effect on asthma control, forced expiratory volume in 1?s or FeNO. Conclusions: A majority of school-age children with persistent asthma may be exposed to ETS, as measured by urinary cotinine, even if their parents insist they don’t smoke in the home. Urinary LTE4 was higher in the ETS-exposed children treated with ICS, but not in children treated with montelukast. 相似文献
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Michelle Sims Susannah Tomkins Ken Judge Gordon Taylor Martin J Jarvis Anna Gilmore 《Addiction (Abingdon, England)》2010,105(3):543-553
Aims To explore trends in and predictors of second‐hand smoke (SHS) exposure in children. To identify whether inequalities in SHS exposure are changing over time. Design Repeated cross‐sectional study with data from eight annual surveys conducted over an 11‐year period from 1996 to 2006. Setting England. Participants Nationally representative samples of children aged 4–15 years living in private households. Measurements Saliva cotinine (4–15‐year‐olds), current smoking status (8–15‐year‐olds), smoking status of parents and carers, smoking in the home, socio‐demographic variables. Findings The most important predictors of SHS exposure were modifiable factors—whether people smoke in the house on most days, whether the parents smoke and whether the children are looked after by carers who smoke. Children from more deprived households were more exposed and this remained the case even after parental smoking status has been controlled for. Exposure over time has fallen markedly among children (59% decline over 11 years in geometric mean cotinine), with the most marked decline observed in the period immediately preceding smoke‐free legislation. Declines in exposure have generally been greater in children most exposed at the outset. For example, in children whose parents both smoke, median cotinine declined annually by 0.115 ng/ml compared with 0.019 ng/ml where neither parent smokes (P < 0.05). Conclusions In the 11 years leading up to smoke‐free legislation in England, the overall level of SHS exposure in children as well as absolute inequalities in exposure have been declining. Further efforts to encourage parents and carers to quit and to avoid smoking in the home would benefit child health. 相似文献