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M Perske 《Canadian Metallurgical Quarterly》1993,46(4):408-9; author reply 410-1
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Periodontal disease seems to be more prevalent in smokers than in nonsmokers. Studies have reported both increases and decreases in gingival blood flow due to smoking. Smoking does not increase the presence of the periodontopathogens Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis and Bacteroides intermedius. Both the chemotaxis and the phagocytic capacity of the polymorphonuclear leukocytes (PMNs) harvested from smokers are lower than with those harvested from nonsmokers. Furthermore, smokers have lower IgA, IgG, IgM, and suppressor CD8 lymphocytes levels than nonsmokers. These differences between smokers and nonsmokers should be taken into account by clinicians during periodontal examinations, therapy, and the healing process.  相似文献   

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Examined the effects of nicotine administration and cigarette smoking on human performance to clarify the role of such effects in controlling smoking. The results of 101 studies (129 experiments) published in scientific journals from 1970 to 1993 were reviewed. In nonabstinent smokers and nonsmokers, nicotine enhanced finger tapping and motor responses in tests of attention; cognitive functioning was not reliably enhanced. It is unlikely that these limited performance-enhancing effects of nicotine play an important role in the initiation of cigarette smoking. In contrast, data from abstinent smokers support the conclusion that nicotine deprivation functions to maintain smoking in nicotine-dependent persons, in part, because nicotine can reverse withdrawal-induced deficits in several areas of performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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Chronic ingestion of ethanol produces a variety of effects on female reproductive function, depending on the dose and the exposure time but the mechanism of alcohol-induced ovarian failure has been little studied. Also the effects of chronic ethanol consumption on the oocyte quality in relation to morphological alterations and PGE synthesis by the oocyte cumulus complexes (OCCs) have not been described. In this study, immature female mice were treated with 10% ethanol in drinking water for 30 days. Then they were induced to superovulate, and at 14, 16 and 20 h post-hCG the quality of the ovarian and oviductal oocytes and PGE production by OCC was determined. At 14 h post-hCG, the percentage of oviductal immature oocytes was increased in the ethanol-treated females (P < 0.05). At 16 h post-hCG, the percent of oviductal activated oocytes was higher in the treated females (P < 0.05), and the ovarian immature oocytes were decreased as compared to the control females (P < 0.05). At 20 h post-hCG, the ethanol-treated females had higher percents of activated oocytes in the oviducts and in the ovaries (P < 0.05) with respect to the controls. PGE synthesis by OCCs, assessed by RIA, was decreased in the treated female mice (P < 0.001). In summary, moderate chronic ethanol treatment in immature female mice can produce morphologic abnormalities in the oocytes (high parthenogenetic activated rates) and altered PGE production in the OCCs.  相似文献   

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BACKGROUND: A systematic quantitative review of the evidence relating parental smoking to the prevalence of asthma and respiratory symptoms was conducted amongst school age children. METHODS: Sixty relevant studies were identified after consideration of 1593 articles selected by electronic search of the Embase and Medline databases using keywords relevant to passive smoking in children. The search was completed in April 1997 and identified 25 studies of asthma, 41 of wheeze, 34 of chronic cough, seven of chronic phlegm and six of breathlessness which were included in a quantitative overview. RESULTS: The pooled odds ratios for either parent smoking were 1.21 (95% CI 1.10 to 1.34) for asthma, 1.24 (95% CI 1.17 to 1.31) for wheeze, 1.40 (95% CI 1.27 to 1.53) for cough, 1.35 (95% CI 1.13 to 1.62) for phlegm, and 1.31 (95% CI 1.08 to 1.59) for breathlessness. Adjustment for confounding had little effect. Evidence of heterogeneity between studies appeared largely explicable by publication bias with a superfluity of small studies with large odds ratios. However, excluding these had little effect on the pooled odds ratios. The prevalence of all symptoms increased with the number of parents who smoked. While maternal smoking had a greater effect than paternal smoking, the effect of father only was clearly significant. CONCLUSIONS: The relationship between parental smoking and respiratory symptoms seems very likely to be causal given statistical significance, robustness to adjustment for confounding factors, consistency of the findings in different countries, and evidence of dose response. The raised risk in households where the father, but not the mother, smoked argues for a postnatal effect.  相似文献   

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Presents alternative conclusions for meta-analyses by D. W. Johnson et al (see record 1981-05387-001) that emphasize interactions between reward systems and situational variables. It is proposed that the effectiveness of a particular reward system in stimulating productivity and achievement will depend on situational variables; no single reward system will always be better than another. The vulnerabilities of meta-analyses are discussed. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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This study was designed to investigate the acute effects of environmental tobacco smoke (ETS) in children with mild asthma during rest and exercise. We studied 13 children [8 males, 5 females; mean age 10 (range 8-13) yr; mean forced expired volume in 1 s (FEV1) 93% (range 82-108%) of predicted] with exercise-induced bronchoconstriction [46 +/- 4% (SE) fall in FEV1 after exercise during cold air breathing]. Children were exposed to ETS (20 ppm carbon monoxide) or ambient air (AA) for 1 h. During the first 54 min of exposure, children were at rest, and during the last 6 min they exercised on a bicycle ergometer (2 W/kg body wt). Spirometry was performed before and during exposure and after exercise. Respiratory symptoms were recorded before and after exposures. In seven children the experiments with AA and ETS were done in duplicate. FEV1 between 5 and 54 min of exposure at rest decreased by 3.2 +/- 0.8% (SE) during AA and by 7.2 +/- 2.3% during ETS exposure compared with preexposure values; the difference between AA and ETS was statistically significant (P = 0.04). The drop in FEV1 was achieved within 5 min and did not change with ongoing exposure. Analysis of individual data revealed that the mean changes during ETS were mainly effected by three children with a significant fall and one child with a significant improvement in FEV1 (P < 0.05). Maximum postexercise fall of FEV1 was 25 +/- 4% after AA and 24 +/- 3% after ETS, which did not differ significantly. Upper and lower respiratory tract symptoms were not significantly different between exposures.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

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BACKGROUND: Several epidemiological studies have suggested an association of passive smoking with coronary heart disease (CHD). However, few studies have taken account of exposure to passive smoking in the workplace. Additionally, several studies have been unable to control for the full range of potential confounding factors. We examined prospectively the relationship of passive smoking with risk of CHD in a cohort of women. METHODS AND RESULTS: The study was carried out in an ongoing prospective cohort of US female nurses, in whom we assessed exposure to passive smoking at home and at work as well as duration of years spent living with someone who smoked regularly. We studied 32046 women 36 to 61 years of age in 1982 who had never smoked and were free of diagnosed CHD, stroke, and cancer. During 10 years of follow-up (1982 to 1992), 152 incident cases of CHD (127 nonfatal myocardial infarction and 25 fatal CHD) occurred. Compared with women not exposed to passive smoking, the relative risks of total CHD-adjusted for a broad range of cardiovascular risk factors-were 1.58 (95% CI, 0.93 to 2.68) among those reporting occasional exposure and 1.91 (95% CI, 1.11 to 3.28) among women reporting regular exposure to passive smoking at home or work. There was no relation apparent between duration of living with a smoker and risk of CHD. CONCLUSIONS: Despite the fact that exposure to passive smoking was assessed by self-report and only at baseline (as well as other limitations), these data suggest that regular exposure to passive smoking at home or work increases the risk of CHD among nonsmoking women.  相似文献   

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This article provides a comprehensive review of the research on smoking and body weight. The relationships between smoking and body weight are evaluated in 70 cross-sectional and longitudinal investigations. The mechanisms responsible for differences in body weight are discussed, the weight-related issues that promote smoking behavior are reviewed, methods for reducing postcessation weight gain are summarized, and future research directions are proposed. A proposed working research model for studying the relationship between smoking, energy balance, and weight gain is offered. It is concluded that smoking and body weight relationships are closely related and pose significant challenges for smoking researchers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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OBJECTIVES: This study tested the hypothesis that women who deliver small-for-gestational-age infants are more often exposed to passive smoking at home or at work. METHODS: Among a 1-year cohort of nulliparous women in the city of Malm?, Sweden 872 (87.7%) women completed a questionnaire during their first prenatal visit. The study was carried out among women whose pregnancies resulted in a singleton live birth (n = 826), 6.7% of infants were classified as small for their gestational age. RESULTS: Passive smoking in early pregnancy was shown to double a woman's risk of delivering a small-for-gestational-age infant, independent of potential confounding factors such as age, height, weight, nationality, educational level, and the mother's own active smoking (odds ratio [OR] = 2.7). A stratified analysis indicated interactional effects of maternal smoking and passive smoking on relative small-for-gestational-age risk. CONCLUSIONS: Based on an attributable risk estimate, a considerable reduction in the incidence of small-for-gestational-age births could be reached if pregnant women were not exposed to passive smoking.  相似文献   

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BACKGROUND: Although smoking cessation is desirable from a public health perspective, its consequences with respect to health care costs are still debated. Smokers have more disease than nonsmokers, but nonsmokers live longer and can incur more health costs at advanced ages. We analyzed health care costs for smokers and nonsmokers and estimated the economic consequences of smoking cessation. METHODS: We used three life tables to examine the effect of smoking on health care costs - one for a mixed population of smokers and nonsmokers, one for a population of smokers, and one for a population of nonsmokers. We also used a dynamic method to estimate the effects of smoking cessation on health care costs over time. RESULTS: Health care costs for smokers at a given age are as much as 40 percent higher than those for nonsmokers, but in a population in which no one smoked the costs would be 7 percent higher among men and 4 percent higher among women than the costs in the current mixed population of smokers and nonsmokers. If all smokers quit, health care costs would be lower at first, but after 15 years they would become higher than at present. In the long term, complete smoking cessation would produce a net increase in health care costs, but it could still be seen as economically favorable under reasonable assumptions of discount rate and evaluation period. CONCLUSIONS: If people stopped smoking, there would be a savings in health care costs, but only in the short term. Eventually, smoking cessation would lead to increased health care costs.  相似文献   

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Objective: This study evaluated the reach, initial effectiveness, and potential moderators and mediators of results of a smoking reduction program. Design: A generally representative sample of 320 adult smokers from an HMO, scheduled for outpatient surgery or a diagnostic procedure, were randomized to enhanced usual care or a theory-based smoking reduction intervention that combined telephone counseling and tailored newsletters. Main Outcome Measures: Self-reported number of cigarettes smoked and carbon monoxide levels. Results: The intervention enrolled 30% of known eligible smokers and produced reductions of 3 cigarettes per day greater than enhanced usual care. Intervention participants were significantly more likely than control participants to achieve at least a 50% reduction in self-reported number of cigarettes using complete cases, imputation analyses, and intent-to-treat procedures. Similar patterns were seen for carbon monoxide results but were significant only in complete case analyses. The intervention was generally robust across patient characteristics (e.g., education, ethnicity, health literacy, and dependence) and phone counselors. Conclusion: Initial results suggest that this program has potential to reach and assist smokers who may not participate in cessation programs. Additional research is indicated to enhance intervention effects, assess maintenance, and evaluate public health impact. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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Women who smoke and breast-feed pose an unknown threat to their infants' health. In this pilot study, relationships between ingestion of nicotine in breast milk and physiologic effects in the infant were investigated. Infant physiologic effects measured were temperature, pulse, respiration, systolic blood pressure, and oxygen saturation. Five smoking and five nonsmoking mother-infant pairs were studied. Breast milk was analyzed for nicotine using gas chromatography. Breast milk from smoking mothers contained a mean of 33.1 ng/mL of nicotine while the breast milk from nonsmoking mothers contained a mean of less than 6.45 ng/mL of nicotine. Infant physiologic measures were taken before and 20 min after breast-feeding. After breast-feeding, infants of smoking mothers had a significant change in respirations and oxygen saturation while infants of nonsmoking mothers had a significant change in pulse only. Results provide a scientific basis for counseling smoking, breast-feeding mothers.  相似文献   

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Angiotensin converting enzyme (ACE) and leucine aminopeptidase (LAP) regulate fetally and maternally generated peptides in the placenta. In this study, ACE-like activity was found to be decreased and LAP-like activity increased with increasing days of gestation in rat placental tissues forming the fetal:maternal interface. Membrane-associated ACE-like and LAP-like activities in the placenta of smokers were also found to be significantly higher than their respective activities in placenta of nonsmokers. Our collective findings suggest that gestational and environmentally-induced changes in placental peptidase activities may account for variable peptide hormone and/or therapeutic peptide metabolism in the placenta.  相似文献   

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