首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到16条相似文献,搜索用时 15 毫秒
1.
The present investigation examined the relationships between anxiety sensitivity and motivation to quit smoking, barriers to smoking cessation, and reasons for quitting smoking among 329 adult daily smokers (160 females; M (age) = 26.08 years, SD = 10.92). As expected, after covarying for the theoretically relevant variables of negative affectivity, gender, Axis I psychopathology, nonclinical panic attack history, number of cigarettes smoked per day, and current levels of alcohol consumption, we found that anxiety sensitivity was significantly incrementally related to level of motivation to quit smoking as well as current barriers to quitting smoking. Partially consistent with the hypotheses, after accounting for the variance explained by other theoretically relevant variables, we found that anxiety sensitivity was significantly associated with self-control reasons for quitting smoking (intrinsic factors) as well as immediate reinforcement and social influence reasons for quitting (extrinsic factors). Results are discussed in relation to better understanding the role of anxiety sensitivity in psychological processes associated with smoking cessation.  相似文献   

2.
Objective: To investigate differences in different aspects of social participation and social capital among baseline daily smokers that had remained daily smokers, become intermittent smokers, or stopped smoking at one year follow up.

Design/setting/participants/measurements: 12 507 individuals, aged 45–69 years, interviewed at baseline between 1992 and 1994 and at a one year follow up were investigated in this longitudinal study. The three groups of baseline daily smokers were compared to the reference population (baseline intermittent smokers and non-smokers) according to different aspects of social participation and social capital. A multivariate logistic regression model was used to assess differences in different aspects of social participation and social capital.

Results: The baseline daily smokers that remained daily smokers at the one year follow up had significantly increased odds ratios of non-participation in study circles in other places than at work, meeting of organisations other than unions, theatre/cinema, arts exhibition, church, sports events, large gatherings of relatives, and private parties compared to the reference population. The baseline daily smokers that had become intermittent smokers at the one year follow up had significantly increased odds ratios of non-participation in church services. The baseline daily smokers that had stopped smoking had increased odds ratios of non-participation in having attended a meeting of organisations other than labour unions during the past year, having been to a theatre or cinema, and of having visited an arts exhibition during the past year. All three categories of baseline daily smokers had significantly decreased odds ratios of non-participation in night club/entertainment.

Conclusions: The baseline daily smokers that had remained daily smokers at the one year follow up had particularly high rates of non-participation compared to the reference population in both activities specifically related to social capital, such as other study circles, meetings of organisations other than labour unions, and church attendance and cultural activities such as theatre/cinema and arts exhibition, although significantly lower participation in cultural activities and meetings of other organisations was also observed among daily smokers that had stopped smoking. All three baseline daily smoker groups had higher rates of having visited a night club during the past year.

  相似文献   

3.
4.
California Tobacco Survey respondents were asked the intensity of their cigarette smoking 1 year previously and at the time of the survey. Respondents reported a generally lower smoking intensity at survey time compared with 1 year previously. Multivariable statistical models on the change in smoking intensity in the past year were fitted to assess the effects of low-tar cigarette use, a quit attempt in the past year, smoking intensity 1 year previously, and demographic variables (age, education, income, and race). The most important predictor of change in intensity was the intensity 1 year previously. The next most important predictor was whether a quit attempt had been made in the previous year. The demographic variables also were found to have a significant effect, although their effects were of smaller magnitude. Low-tar cigarette use was not a significant predictor of change in intensity in multivariable analysis. The effect of a quit attempt on the reduction in intensity of smoking suggests that periods of cessation may reduce the intensity of smoking and the level of addiction for several months following relapse. Consequently, it may be important to control for cessation activity in studies comparing exposures from conventional tobacco products to exposures from new products that purport to offer lower harm.  相似文献   

5.
6.
OBJECTIVE: To estimate health expectancy--that is, the average lifetime in good health--among never smokers, ex-smokers, and smokers in Denmark. DESIGN: A method suggested by Peto and colleagues in 1992 for estimating smoking attributable mortality rates was used to construct a life table for never smokers. This life table and relative risks for death for ex-smokers and smokers versus never smokers were used to estimate life tables for ex-smokers and smokers. Life tables and prevalence rates of health status were combined and health expectancy was calculated by Sullivan's method. SETTING: The Danish adult population. MAIN OUTCOME MEASURES: The expected lifetime in self rated good health or without longstanding illness for never smokers and smokers. RESULTS: The expected lifetime of a 20 year old man who will never begin to smoke is 56.7 years, 48.7 (95% confidence interval (CI), 46.8 to 50.7) years of which are expected to be in self rated good health. The corresponding figures for a man who smokes heavily are 49.5 years, 36.5 (95% CI 35.0 to 38.1 ) years of which are in self rated good health. A 20 year old woman who will never begin to smoke can expect to live a further 60.9 years, with 46.4 (95% CI 44.9 to 47.8) years in self rated good health; if she is a lifelong heavy smoker, her expected lifetime is reduced to 53.8 years, 33.8 (95% CI 31.7 to 35.9) years of which are in self rated good health. Health expectancy based on long standing illness is reduced for smokers when compared with never smokers. CONCLUSIONS: Smoking reduces the expected lifetime in good health and increases the expected lifetime in poor health.  相似文献   

7.
The study investigated the effects of reducing daily herbage allowance (DHA) from 15.0 to 11.8 kg dry matter per cow (>3.5 cm post grazing sward height) to a spring-calved herd during early lactation on the composition, rennet coagulability and heat stability characteristics of milk during early lactation (EL, 29–70 days in milk, DIM), mid lactation (ML, 78–183 DIM), and late lactation (LL, 205–267 DIM). Samples of milk were taken at approximate 10 d intervals during EL and at 1–3 week intervals during ML and LL. Reducing DHA led to reductions in milk yield, milk solids yield, and concentrations of protein (∼0.22%, w/w) and casein (0.13%, w/w) during EL. Otherwise, it had little effect on milk composition or on the selected processing characteristics in ML, LL or overall lactation. Stage of lactation resulted in comparatively large changes in most compositional parameters, rennet gelation and heat stability.  相似文献   

8.

Objectives

To establish the effect of preoperative smoking cessation on the risk of postoperative complications, and to identify the effect of the timing of preoperative cessation.

Data sources

The Cochrane Library Database, PsycINFO, EMBASE, Medline, and CINAHL databases were searched, using the terms: “smoking”, “smoking‐cessation”, “tobacco‐use”, “tobacco‐abstinence”, “cigarett$”, “complication$”, “postoperative‐complication$”, “preoperative”, “perioperative” and “surg$”. Further articles were obtained from reference lists. The search was limited to articles on adults, written in English and published up to November 2005.

Study selection

Prospective cohort designs exploring the effects of preoperative smoking cessation on postoperative complications were included. Two reviewers independently scanned abstracts of relevant articles to determine eligibility. Lack of agreement was resolved through discussion and consensus. Twelve studies met the inclusion criteria.

Data extraction

Methodological quality was assessed by both reviewers, exploring validation of smoking status, clear definition of the period of smoking cessation, control for confounding variables and length of follow‐up.

Data synthesis

Only four of the studies specified the exact period of smoking cessation, with six studies specifying the length of the follow‐up period. Five studies revealed a lower risk or incidence of postoperative complications in past smokers than current smokers or reported that there was no significant difference between past smokers and non‐smokers.

Conclusions

Longer periods of smoking cessation appear to be more effective in reducing the incidence/risk of postoperative complications; there was no increased risk in postoperative complications from short term cessation. An optimal period of preoperative smoking cessation could not be identified from the available evidence.  相似文献   

9.
An experiment was conducted to determine the effects of different milking frequencies on entire lactation production performance in Holstein cows. One hundred twenty Holstein cows were assigned to 3 milking treatments (35 multiparous and 5 primiparous cows in each): 1) milking 6 times daily for the entire lactation (6×); 2) milking 6 times daily for the first 90 d in milk (DIM) and switching to 3 times daily milking afterward (6×-3×); and 3) milking 3 times daily for the entire lactation (3×). Milk yield was recorded every other day during the first 60 DIM and on 2 consecutive days per week subsequently. Cows were weighed and scored for their body condition immediately after parturition and monthly afterward. Blood and milk samples were taken from each cow on 30, 60, 90, 120, 150, 210, and 270 DIM, with an additional blood sampling on 15 DIM. Milk and fat corrected milk yield was greater for 6× and 6×-3× cows than for 3× cows (36.82, 37.32, and 36.1, 36.75 versus 34.56, 35.33 kg/d, respectively) during the experimental period. Milk fat and lactose percentage were not different among treatments, but milk protein was lower in 6× cows than in 6×-3× and 3× cows. Blood glucose concentration was higher and blood nonesterified fatty acids and β-hydroxybutyrate concentration were lower in 3× cows than in 6× and 6×-3× cows during early lactation. Dry matter intake was greater in 6× cows than in 6×-3× and 3× cows (23.05, 22.58, and 22.45 kg/d, respectively). The 3× cows began to gain weight earlier than the 6× and 6×-3× cows, but there was no difference among groups for BW change regarding the entire experimental period. These results indicate that increasing milking frequency to 6 times daily increases milk yield only during early lactation and that there are no advantages of milking 6 times daily compared with 3 times daily during the mid and late lactation periods. Given the results of this study and the economical aspects of production, milking 6 times daily until 90 DIM and subsequently switching to milking 3 times daily is preferred.  相似文献   

10.
OBJECTIVE: To monitor the effect of a novel nicotine delivery device that may produce fewer carcinogens (Eclipse) on cigarette smoking, carbon monoxide and nicotine concentrations, and motivation to give up smoking. The smoker's own brand of cigarette and a nicotine replacement product (Nicotrol inhaler) were used as comparisons. DESIGN: After baseline data were recorded, smokers were randomised to either Eclipse or inhaler for two weeks and then switched to the other product for another two weeks. Thereafter a second baseline was obtained. SETTING AND PARTICIPANTS: Fifty smokers were included and data are reported for the 40 with complete data sets. The smokers were not trying to quit but were interested in trying a new product to reduce their risk. They visited a smoking clinic 10 times during the six week period of the trial. INTERVENTION: No counselling to aid reduction by Eclipse or inhaler was given. MAIN OUTCOME MEASURES: At each visit smoking status and carbon monoxide concentrations were recorded. In half of the visits withdrawal symptoms, attitudes towards smoking, heart rate, and blood nicotine concentrations were also recorded. RESULTS: Eclipse use decreased the number of cigarettes smoked per day (cpd) from 19.1 cpd at baseline to 2.1 cpd (p < 0.001), but increased carbon monoxide concentrations in parts per million (ppm) from 21.0 ppm to 33.0 ppm (p < 0.001). A similar decrease in cigarettes smoked per day was seen with the Nicotrol inhaler, from 19.1 cpd to 4.8 cpd (p < 0.001), but carbon monoxide decreased from 21.0 ppm to 12.7 ppm (p < 0.001). The blood nicotine concentration remained fairly stable with Eclipse, increasing slightly from 16.8 ng/ml to 18.0 ng/ml, while for the inhaler a significant drop was noted, from 16.8 ng/ml to 12. 2 ng/ml (p < 0.002). Craving and withdrawal did not increase with Eclipse. Few significant adverse events occurred with Eclipse. CONCLUSIONS: Eclipse can dramatically decrease cigarette consumption without causing withdrawal symptoms or decreases in nicotine concentrations or motivation to quit altogether. Unlike the inhaler, Eclipse produces an increase in carbon monoxide concentration. Thus Eclipse may not be a safer cigarette.  相似文献   

11.
Scope : Decreasing postprandial glycaemic excursions may have a beneficial effect on inflammatory and oxidative stress profiles. In this study, we investigated the impact of carbohydrate digestibility modulation per se, as a means of reducing the glycaemic response, on metabolic and inflammatory responses in subjects with metabolic risk factors. Methods and results : Twenty healthy subjects with metabolic risk consumed a cereal product either high in Slowly Digestible Starch (HSDS) or low in SDS (LSDS) at breakfast daily for 3 weeks, in a cross‐over design. Following each 3‐week session, postprandial glycaemia, insulinaemia, the lipid profile, inflammation and oxidative stress markers were assessed and compared to those induced by ingestion of a glucose solution (as a reference). The 2‐h glycaemic and insulinaemic responses were significantly lower following the HSDS breakfast compared with the LSDS breakfast or glucose. No significant differences between the products were observed in terms of the lipid profile, C‐reactive protein, IL‐6 and tumour necrosis factor alpha. We observed a slight increase in fasting lipid peroxidation markers, including an increase in plasma malondialdehyde (MDA) and a decrease in whole blood glutathione (GSH), without significant alteration of urinary F2‐isoprostanes or plasma glutathione peroxidase (GPx) activity. Conclusion : Consumption of HSDS products for 3 weeks significantly altered both postprandial glycaemia and insulinaemia, but was not sufficient to modify the inflammatory profile. Consumption of both cereal products was associated with a slightly higher fasting oxidative stress profile.  相似文献   

12.
Commercially slaughtered and dressed beef carcass sides (n=30) were followed through a standard commercial chill unit fitted with a new "Jasca" air humidification system adjusted to provide intermittent water spraying of carcass sides (spray cycle 2 min on, 1 min off) for 15 h. Immediately after dressing, and after 24h in the chill unit, the surface water activity, and the weight of each side was measured, and 5 cm2 samples were recovered from four locations, i.e. rump, flank, brisket and neck on the surface of each side. These samples, and similar samples from control sides (n=30) processed in a standard commercial chill unit, were subjected to microbiological examination by direct and resuscitation counts on plate count agar (PCA), MacConkey agar (MAC) and violet red bile glucose agar (VRBGA). No significant differences were observed between bacterial numbers on test and control samples on each of the above agars, at each sample point/occasion. Comparison of direct and resuscitation counts suggested the presence of substantial numbers of injured cells, at both stages (pre- and post-chill), on test and control sides. After 24 h in chill units, test sides exhibited an average weight loss of 1.36% (+/-0.36%), which is significantly less (P<0.001) than the average weight loss (1.55%+/-0.24%) from control sides. These results suggest that the Jasca spray-chilling system can limit carcass shrinkage (on average by 0.19%) without significantly increasing the surface populations of selected bacterial groups.  相似文献   

13.
14.
It has been speculated that body weight and concern about body weight are important factors in initiation of tobacco use among adolescents, particularly females. An examination of studies that have explored these relationships can provide important information on possible underlying mechanisms that could be used for prevention interventions. This review summarizes recent studies examining weight concerns and youth smoking, with a focus on gender differences. These studies were integrated with the few studies that have examined the relationship between actual body weight and smoking among adolescents. A total of 55 primary research articles met inclusion criteria for the review. Of these, 19 studies assessed the relationship between body weight and smoking, and 50 studies addressed weight concerns and smoking. Some evidence indicated a positive relationship between smoking and body weight among adolescents, although not all studies found a positive association. In terms of the relationship between weight concerns and adolescent smoking, the amount of evidence supporting a positive association differed depending on the dimension of weight concern considered, with the strongest evidence for dieting behaviors. For dieting behaviors, disordered eating symptoms, and some aspects of general weight concerns, the positive relationship with smoking was more consistent among female adolescents than among male adolescents. Possible explanations for these findings are discussed, and priorities for future research are identified.  相似文献   

15.
The use of edible coating has proved a valuable tool in improving the efficiency of osmotic dehydration (OD) of plant material. In this study the impact of edible coating with or without an anti-microbial agent (A–M) on microbial growth was investigated. Potato cylinders (15 × 57 mm — D × L) were used as a model plant material. Calcium alginate (CA) coating was applied with or without incorporation of potassium sorbate (PS), at 0.3% of sample weight (before coating). OD took place for 3 h in stirred jars using sucrose solution at 50 °Brix and 40 °C. Microbial growth (Aerobic Plate Count — APC) was monitored both during OD (3 h) and during refrigerated storage at 5 °C (14 days). During OD, a significant reduction of the initial microbial load (ML) in the control (non-coated) treatment was observed, possibly due to a microbial “wash-out” effect. Both coating treatments resulted in a marginal decrease of initial ML in the OD product, suggesting some kind of protection against this effect. During refrigerated storage, the use of coating resulted in reaching the growth plateau several days earlier, which lead to significant reduction of maximum ML, compared to the control treatment. Besides this benefit, coating with A–M helped extend the lag phase and postpone time to reach maximum load by almost 4 days, compared to the simple coating treatment. These results can support further work on the use of more effective types and concentrations of preferably natural anti-microbials to achieve satisfactory stabilization of osmo-dehydrated/refrigerated products, without a negative impact on their minimal processing profile.

Industrial relevance

Osmotic dehydration is a very potent processing tool that has been studied extensively in terms of mass transfer phenomena. Yet, microbial studies in this area are rather scarce; thus industrial applications are very difficult to proceed, due to lack of microbial stabilization data. This is especially crucial in the case of combined, minimal processing methods, such as osmotic dehydration and refrigeration. This work is using edible coating (which is known to promote dehydration efficiency) to incorporate a common anti-microbial agent, in an effort to establish an effective series of hurdles leading to microbial stabilization of osmo-dehydrated, refrigerated products.  相似文献   

16.
The present study investigated production responses and ruminal fermentation characteristics of lactating dairy cows when supplemented with N-acetyl-l-Met (NALM) as a source of rumen-protected Met in metabolizable protein (MP)-deficient (MPD) or MP-adequate diet (MPA). Eight lactating dairy cows (53 ± 10.4 d in milk, average ± standard deviation) were blocked by parity and days in milk, and the experiment was performed in a replicated 4 × 4 Latin square design. Within each square, cows were randomly assigned to a sequence of 4 diets during each of the four 21-d periods (14 d of treatment adaptation and 7 d of data collection and sampling). A 2 × 2 factorial arrangement was used; MPD or MPA was combined without or with NALM: MPD without NALM, MPD with NALM (MPD+NALM), MPA without NALM, and MPA with NALM (MPA+NALM). A NALM product was supplemented in the MPD+NALM and the MPA+NALM at 30 g/cow per d. Supplementation of NALM did not affect dry matter intake (DMI) and milk yield regardless of MP concentration. In addition, supplementing NALM resulted in a similar milk true protein concentration and yield. In contrast, NALM supplementation increased milk fat concentration and yield and 3.5% fat-corrected milk yield and tended to increase energy-corrected milk yield regardless of MP difference. Additionally, trends were observed for increased 3.5% fat-corrected milk yield/DMI and energy-corrected milk yield/DMI, and the positive effects were greater under the MPA than the MPD diet, resulting in trends toward interactions between MP and NALM. Dietary treatments had similar effects on ruminal fermentation characteristics and microbial protein yield. Plasma concentration of Met increased under the MPD but not the MPA diet, leading to an MP × NALM interaction. Overall results in the current study suggest that NALM exerted a minor influence on ruminal metabolism, but increased milk fat concentration, resulting in increases in milk fat yield and feed efficiency. Yet, potential effects of NALM on intermediary metabolism between the gastrointestinal tract, the liver, and the mammary gland need to be explored to understand utilization efficiency for production of dairy cows.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号