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31.
Objective: This study examined the relationship between internalization of negative weight‐based stereotypes and indices of eating behaviors and emotional well‐being in a sample of overweight and obese women. Research Method and Procedures: The sample was comprised of 1013 women who belonged to a national, non‐profit weight loss organization. Participants completed an on‐line battery of self‐report questionnaires measuring frequency of weight stigmatization and coping responses to deal with bias and symptoms of depression and self‐esteem, attitudes about weight and obesity, and binge eating behaviors. In addition, participants were asked to list the most common weight‐based stereotypes and whether they believed them to be true or false. Results: Participants who believed that weight‐based stereotypes were true reported more frequent binge eating and refusal to diet in response to stigma experiences compared with those who reported stereotypes to be false. The degree to which participants believed stereotypes to be true or false was not related to types or amount of stigma experiences reported, self‐esteem, depression, or attitudes toward obese persons. In addition, engaging in weight loss strategies as a response to bias was not predicted by stereotype beliefs or by actual stigma experiences, regardless of the amount or types of stigma reported. Discussion: These findings suggest that obese individuals who internalize negative weight‐based stereotypes may be particularly vulnerable to the negative impact of stigma on eating behaviors and also challenge the notion that stigma may motivate obese individuals to engage in efforts to lose weight. This study highlights a new area of research that warrants attention to better understand weight stigma and its potential consequences for health.  相似文献   
32.
Objective: Eating in the absence of hunger (EAH) may be a genetically influenced phenotype of overweight children, but evidence is limited. This research evaluated the heritability (h2) of EAH and its association with overweight among Hispanic children 5 to 18 years old. Genetic and environmental associations of EAH with overweight, fat mass, and key hormonal regulators of food intake were also evaluated. Research Methods and Procedures: A family design was used to study 801 children from 300 Hispanic families. Weighed food intakes were used to measure EAH after an ad libitum dinner providing 50% of estimated energy needs. Fasting ghrelin, amylin, insulin, and leptin were measured by immunoassays. Measured heights, weights, and fat mass (using DXA) were obtained. Total energy expenditure (TEE) was measured by room respiration calorimetry. Results: On average, children consumed 41% of TEE at the dinner meal, followed by an additional 19% of TEE in the absence of hunger. Overweight children consumed 6.5% more energy at dinner (p < 0.001) and 14% more energy in the absence of hunger (p < 0.001) than non‐overweight children. Significant heritabilities were seen for EAH (h2 = 0.51) and dinner intake (h2 = 0.52) and for fasting levels of ghrelin (h2 = 0.67), amylin (h2 = 0.37), insulin (h2 = 0.37), and leptin (h2 = 0.34). Genetic correlations were seen between eating behavior and fasting hormones, suggesting common underlying genes affecting their expression. Discussion: This research provides new evidence that overweight Hispanic children exhibit elevated levels of hyperphagic eating behaviors that are influenced by genetic endowment.  相似文献   
33.
Objective: The objective was to investigate whether calcium intake is independently associated with body fat in peripubertal girls. Research Methods and Procedures: A total of 45 healthy premenarcheal girls (initially 10.5 ± 0.6 years of age) completed a 2‐year prospective observational study. Percent body fat and trunk fat (by DXA), height, weight, maturational stage, and eating attitudes (children's Eating Attitudes Test [EAT]) were measured at baseline and at 1 and 2 years. Physical activity (by questionnaire) and calcium intake (by calcium‐specific food frequency questionnaire and 3‐day food records) were assessed at 6‐month intervals. Results: Girls with 2‐year mean calcium intake below and above the median had similar age, height, lean mass, and maturational stage at baseline, but girls below the median had significantly higher baseline percentage body fat (29.3 ± 10.3% vs. 22.0 ± 6.8%, p < 0.01) and trunk fat (24.2 ± 10.6% vs. 15.8 ± 6.8%, p < 0.01). However, differences were no longer significant when covariates (most notably children's EAT dieting score) were considered. Regression analysis revealed that dieting score was a consistent positive predictor of percentage body and trunk fat at all cross‐sectional time‐points, accounting for >20% of the variance, but did not predict 2‐year change in percentage fat. Calcium intake did not enter longitudinal regression equations for 2‐year change in percentage fat. Discussion: In this group of girls, an inverse cross‐sectional association between calcium intake and body fat appeared to result from avoidance of foods high in calcium by girls who were concerned about their body weight or shape. Calcium intake was not associated with change in fat over time.  相似文献   
34.
Objective: The objective was to test the hypothesis that, in women, the association between obesity and impairment in psychosocial functioning is mediated by levels of weight and shape concerns and/or binge‐eating frequency. Research Methods and Procedures: Self‐report measures of eating disorder psychopathology, mental health functioning, subjective quality of life in the psychological and social domains, and days “out‐of‐role” associated with any (physical or mental) health problem, were completed by a community sample of women classified as obese (BMI ≥30 kg/m2, n = 639) or non‐obese (BMI <30 kg/m2, n = 4253). For each of the dependent measures, regression models were used to test the hypothesis of mediation by comparing the strength of the relationship between independent and dependent variables with and without inclusion of the putative mediator in the regression model. Results: On each measure, the conditions for perfect mediation were satisfied when weight or shape concerns acted as the putative mediator, indicating that there was no association between obesity and functional impairment after controlling for weight or shape concerns. In contrast, associations between obesity and impairment in psychosocial functioning remained highly significant when binge‐eating frequency was the putative mediator. Discussion: The findings suggest that in women, weight and shape concerns are an important mediator of the relationship between obesity and impairment in psychosocial functioning, whereas binge eating may not be of primary importance. A greater focus on body acceptance in obesity treatment may be indicated.  相似文献   
35.
Objective: To assess whether parental overweight status and disinhibited overeating are predictive of daughters’ accelerated weight gain and disinhibited overeating. Research Methods and Procedures: Participants were part of a longitudinal study of girls (N = 197) and their parents. Measured height and weight were used to calculate BMI [weight (kilograms)/height (meters)2]. Parents’ disinhibited eating behavior was assessed using the Eating Inventory. Girls’ disinhibited eating was assessed using a behavioral protocol to measure eating in the absence of hunger. Girls were classified based on parental overweight at study entry into four groups: neither, mother only, father only, or both parents overweight. Results: Girls with both parents overweight had the most rapid increases in BMI from 5 to 13 years of age; BMI increased most slowly among the neither parent overweight group, with intermediate increases in BMI among mother only and father only overweight groups. Daughters with both parents overweight at study entry were eight times more likely to be overweight at age 13, controlling for daughters’ weight at age 5. Girls with both parents overweight had higher levels of disinhibited eating across all ages than all other groups. Although girls in all parental weight status groups showed increases in disinhibited eating over time, girls with both parents overweight had larger increases in disinhibited eating over time compared with all other groups. Discussion: Girls growing up in families differing in parental overweight had divergent developmental trajectories for BMI and disinhibited overeating. Findings reveal the need to focus prevention efforts on overweight parents of young children.  相似文献   
36.
Objective: The aim was to investigate the association between breakfast consumption and long‐term weight gain in an adult male population. Research Methods and Procedures: We evaluated prospective data on 20,064 U.S men, 46 to 81 years of age, who participated in the Health Professionals Follow‐up Study. Data on body weight, dietary factors, and lifestyle variables were obtained by validated questionnaires. We examined weight gain during 10 years of follow‐up. Results: Overall, 5857 men had a weight gain of 5 kg or greater during 10 years of follow‐up. Breakfast consumption was inversely associated with the risk of 5‐kg weight gain after adjustment for age [hazard ratio (HR) = 0.77 (95% confidence interval [CI], 0.72 to 0.82)], and this association was independent of lifestyle and BMI at baseline [HR = 0.87 (95% CI, 0.82 to 0.93)]. Fiber and nutrient intakes partially explained the association between breakfast consumption and weight gain. The inverse association between breakfast consumption and weight gain was more pronounced in men with a baseline BMI of 25 kg/m2 or lower [multivariate HR = 0.78 (95% CI, 0.70 to 0.87)] than in men who were overweight at baseline [HR = 0.92 (95% CI, 0.85 to 1.00)]. Furthermore, we observed that an increasing number of eating occasions in addition to three standard meals was associated with a higher risk of 5‐kg weight gain [HR = 1.15 (95% CI, 1.06 to 1.25, for ≥2 vs. 0 additional eating occasions)]. Discussion: These findings suggest that the consumption of breakfast may modestly contribute to the prevention of weight gain as compared with skipping breakfast in middle‐aged and older men.  相似文献   
37.
Osteoporosis is an important public health problem worldwide. Among the countries with a very high population risk of fractures, there are those with the highest level of economic development. Osteoporotic fractures are the main cause of disability among elderly people, and the resultant disabilities require particularly large financial support associated not only with the direct treatment of the fracture but also with the necessity for long-term rehabilitation and care for the disabled person. Many well-established factors can have impact on bone mass and fracture risk. Recently, it has been hypothesized that working during nighttime which leads to endocrine disorders may have an indirect impact on bone physiology among night shift workers. Therefore, it can be presumed that the night shift work may contribute to the etiology of osteoporosis. The aim of our work was to make a review of the epidemiological evidence on the association between night shift work and bone mineral density or fracture risk as well as to discuss the potential biological mechanisms linking the work under this system with the development of osteoporosis. We have identified only four studies investigating the association between system of work and bone mineral density or fracture risk among workers. The findings of three out of four studies support the hypothesis. None of the studies has investigated a potential relationship between night shift work and bone turnover markers. Given that there have been no epidemiological studies in European countries that would concern working populations and the noticeable difference in the risk of osteoporosis between communities, further studies are warranted to elucidate the problem. It is presumed that further in-depth studies will not only identify the underlying factors of the disease but also contribute to developing guidelines for policy makers and employers for primary prevention of osteoporosis in workplace.  相似文献   
38.
Two approaches to determine the fraction (μ) of mitochondrial respiration sustained during illumination by measuring CO2 gas exchange are compared. In single leaves, the respiration rate in the light (`day respiration' rate Rd) is determined as the ordinate of the intersection point of A–ci curves at various photon flux densities and compared with the CO2 evolution rate in darkness (`night respiration' rate Rn). Alternatively, using leaves with varying values of CO2 compensation concentration (Γ), intracellular resistance (ri) and Rn, an average number for μ can be derived from the linear regression between Γ and the product riċRn. Both methods also result in a number c* for that intercellular CO2 concentration at which net CO2 uptake rate is equal to –Rd. c* is an approximate value of the photocompensation point Γ* (Γ in the absence of mitochondrial respiration), which is related to the CO2/O2 specificity factor of Rubisco Sc/o. The presuppositions and limitations for application of both approaches are discussed. In leaves of Nicotiana tabacum, at 22 °C, single leaf measurements resulted in mean values of μ = 0.71 and c* = 34 μmol mol−1. At the photosynthetically active photon flux density of 960 μmol quanta m−2 s−1, nearly the same numbers were derived from the linear relationship between Γ and riċRn. c* and Rd determined by single leaf measurements varied between 31 and 41 μmol mol−1 and between 0.37 and 1.22 μmol m−2 s−1, respectively. A highly significant negative correlation between c* and Rd was found. From the regression equation we obtained estimates for Γ* (39 μmol mol−1), Sc/o (96.5 mol mol−1) and the mesophyll CO2 transfer resistance (7.0 mol−1 m2 s). This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
39.
Aims: To evaluate food choice and eating difficulty experienced by older Greek edentate patients. Subjects: Three samples of patients seeking provision of replacement dentures were studied. A primary study of urban mainland U1 (n=54) and island rural R1 samples (n=84) was followed by a mainland urban U2 sample (n=119) in the Secondary study. Setting: Greek dental clinics. Intervention: Semi‐structured interviews (SSI) were employed, using both open and closed questions. Design: The primary study used SSI to identify eating difficulty experienced by two culturally different Greek groups. The secondary study established patterns of difficulty for comparisons between an urban Greek population and northern European urban studies. Main Outcome Measures: The prevalence of eating difficulty, the degree of difficulty eating specified foods and the exclusion of foods because difficult. Results: Most patients expressed difficulty eating at least one type of food, a high percentage of these patients were willing to eat foods found difficult, while others use particular methods of food preparation that make food easier to eat. Chicken illustrated the importance of specifying the method of cooking when questioning eating difficulties. Roast meats provided insight into the more difficult end of the food range. Raw vegetables were rated difficult. Apples and oranges were also food of particular interest. Conclusions: The semi‐structured interview method provides a succesful method to identify eating difficulty and food choices by older Greek complete denture wearers. Differences, probably largely cultural, were identified between Greek island rural and mainland urban communities. Greek food choices differed favourably from an English sample, strikingly in that Greek patients report continuing to eat difficult foods despite difficulty eating them. This may be relevant to health data on Greek populations that show better mortality statistics despite adverse factors such as high prevalence of smoking.  相似文献   
40.
In many plant species, including chrysanthemum, a strong positive correlation between internode length and DIF [difference between day (DT) and night (NT) temperature] has been observed. However, Langton and Cockshull (1997. Scientia Horticulturae 69: 229-237) reported no such relationship and showed that absolute DT and NT explained internode length rather than DIF. To investigate these conflicting results and to clarify the validity of the DIF concept, cut chrysanthemums (Chrysanthemum 'Reagan Improved') were grown in growth chambers at all 16 combinations of four DT and four NT (16, 20, 24 and 28 degrees C) with a 12 h day length. Length of internode 10, number of internodes and stem length were measured on days 5, 10, 17, 22 and 27 after starting the temperature treatments. Internode length on day 10 showed a positive linear relationship with DIF (R2 = 0.64). However, when internodes had reached their final length in all treatments (day 27), a much stronger positive linear relation was observed (R2 = 0.81). A model to predict final internode length was developed based on the absolute DT and NT responses: both responses were optimum curves and no significant interaction between DT and NT occurred [final internode length (mm) = -32.23 + 3.56DT + 1.08NT - 0.0687DT2 - 0.0371NT2; R2 = 0.91, where TD is day temperature and TN is night temperature]. It is shown that DIF can predict final internode length only within a temperature range where effects of DT and NT are equal in magnitude and opposite in sign (18-24 degrees C). Internode appearance rate, as well as stem length formed during the experiment, showed an optimum response to DT.  相似文献   
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