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Objective: Studies on weight change and mortality have yielded inconclusive results. This 10‐year prospective study was undertaken to improve understanding of factors affecting weight change. Research Methods and Procedures: The subjects were 1143 men, aged 36 to 88 years (mean, 53.3 years) at entry. A questionnaire was filled in at entry and at the end of the follow‐up with queries on weight, height, weight at the age of 20, physician‐diagnosed diseases, smoking, alcohol use, dietary habits, leisure physical activity, occupation, present occupational activity, living conditions (living alone or cohabiting), and former athletic status. Further information on morbidity was obtained from selected national registers. Factors predicting weight change during the study were identified by stepwise linear multiple regression analysis. Results: The mean 10‐year weight change was 0.8 (range, ?29 to +24) kg. Age at entry (β‐coefficient, ?0.17, SE 0.02), weight at entry (β, ?0.03, SE 0.01), diabetes at entry (β, ?3.55, SE 1.02), diabetes diagnosed after entry (β, ?3.94, SE 0.96), malignant cancer (β, ?1.60, SE 0.70), being a smoker (β, ?1.59, SE 0.48), and increased physical activity (β, ?1.27, SE 0.54) were significantly (p < 0.05) associated with weight loss in the final model. The model explained 13% of the variance of weight change. Discussion: The results emphasize the complexity of weight change. Some factors associated with weight change are apparently negatively, and some positively, associated with health. This could explain the equivocal findings on weight change and mortality in the literature.  相似文献   
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There are four main ideas in relapse prevention. First, relapse is a gradual process with distinct stages. The goal of treatment is to help individuals recognize the early stages, in which the chances of success are greatest. Second, recovery is a process of personal growth with developmental milestones. Each stage of recovery has its own risks of relapse. Third, the main tools of relapse prevention are cognitive therapy and mind-body relaxation, which are used to develop healthy coping skills. Fourth, most relapses can be explained in terms of a few basic rules. Educating clients in these rules can help them focus on what is important: 1) change your life (recovery involves creating a new life where it is easier to not use); 2) be completely honest; 3) ask for help; 4) practice self-care; and 5) don’t bend the rules.  相似文献   
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Eutrophication resulting from nutrient enrichment decreases water quality and harms ecosystem structure and function, and its degree is significantly affected by land use in the catchment. Quantifying the relationship between eutrophication and land use can help effectively manage land use to improve water quality. Previous studies principally utilized land use quantity as an indicator to link water quality parameters, but these studies lacked insight into the impact of land use intensity. Taking the upper catchment of Miyun Reservoir as a case study, we developed a method of aggregating land use quantity and intensity to build a new land use indicator and tested its explanatory power on water quality. Six nutrient concentrations from 52 sub-watersheds covering the whole catchment were used to characterize the spatial distribution of eutrophication. Based on spatial techniques, empirical conversion coefficients, remote sensing data, and socio-economic statistical data, land use intensity was measured and mapped visually. The new land use indicator was calculated and linked to nutrient concentrations by Pearson correlation coefficients. Results demonstrated that our new indicator incorporating intensity information can quantify the different nutrient-exporting abilities of different land use areas. Compared to traditional indicators that only incorporate land use quantity, most Pearson correlation coefficients between the new indicator and water nutrient concentrations increased. This new information enhanced the explanatory power of land use on water nutrient concentrations, and so will be able to help us understand the impact of land use on water quality and guide decision making for better land use management.  相似文献   
5.
Water scarcity is a widespread problem in many parts of the world. Most previous methods of water scarcity assessment only considered water quantity, and ignored water quality. In addition, the environmental flow requirement (EFR) was commonly not explicitly considered in the assessment. In this study, we developed an approach to assess water scarcity by considering both water quantity and quality, while at the same time explicitly considering EFR. We applied this quantity–quality-EFR (QQE) approach for the Huangqihai River Basin in Inner Mongolia, China. We found that to keep the river ecosystem health at a “good” level (i.e., suitable for swimming, fishing, and aquaculture), 26% of the total blue water resources should be allocated to meet the EFR. When such a “good” level is maintained, the quantity- and quality-based water scarcity indicators were 1.3 and 14.2, respectively; both were above the threshold of 1.0. The QQE water scarcity indicator thus can be expressed as 1.3(26%)|14.2, indicating that the basin was suffering from scarcity problems related to both water quantity and water quality for a given rate of EFR. The current water consumption has resulted in degradation of the basin's river ecosystems, and the EFR cannot be met in 3 months of a year. To reverse this situation, future policies should aim to reduce water use and pollution discharge, meet the EFR for maintaining healthy river ecosystems, and substantially improve pollution treatment.  相似文献   
6.
The Steven–Johnson syndrome (SJS) is characterized by a sudden onset of mucous membrane erosion (predominantly oral mucosa, lips, and conjunctivae) with widespread blistering of the skin involving up to 10% of the body surface area. It is almost always a drug-related reaction, although it can be caused by infections and immunizations. A 33-year-old man with recent diagnosis of HIV infection developed antiretroviral treatment (ART)-associated SJS. Physical activity and sleep parameters were recorded by wrist actigraphy in four different consecutive scenarios: baseline assessment, first ART regimen, hospitalization, and second ART regimen. Significant differences were observed in physical activity patterns between the four phases. No differences in sleep parameters were found. To our knowledge, this is the first study recording physical activity changes and sleep during a SJS reaction.  相似文献   
7.
Light and dark phase training may influences rodents’ physiologic parameters because these animals have nocturnal habits. Thus, we verify the effects of the training in different photoperiods on metabolism and corporal composition of rats. Eighteen rats were divided into three groups – G1: non-trained; G2: trained in the light phase; G3: trained in the dark phase. Rats were allowed to swim for 60 min, five times per week during six weeks. Trained animals presented a smaller weight gain and fat percentage in carcass. Rats of G3 increased gastrocnemius relative weight. The adipocyte diameter of G3 rats was smaller than the other groups. The levels of the total cholesterol, low-density proteins, and triacylglycerols were decreased in animals of G2 while the glycemia was increased. Training in light phase provided more alterations in the blood biochemical profile while the training in the dark increased the gastrocnemius weight and decreased the diameter of the adipocyte.  相似文献   
8.
Trichomes are an important physical resistance mechanism of plants, as they reduce insect herbivore movement, feeding, and digestion. However, we know little about how trichomes influence herbivore distributions and populations. We conducted laboratory and field experiments to evaluate the preferences of Platyprepia virginalis (Boisduval) (Lepidoptera: Arctiidae) caterpillars to natural and manipulated densities of trichomes on their primary food, Lupinus arboreus Sims (Fabaceae). We then conducted field surveys to determine whether variation in trichome density among lupine bushes affected caterpillar spatial distribution on the landscape. Platyprepia virginalis caterpillars preferred lupine leaves with fewer trichomes in choice and no‐choice experiments. In the field, caterpillar feeding damage was found more often on leaves with fewer trichomes. These preferences scaled up to the level of bushes in the landscape such that more caterpillars were found on bushes with lower trichome densities than on bushes with higher trichome densities. This is one of few studies to show the potential for trichome density to influence herbivore population size and distribution in a natural system at a landscape level. The results are consistent with trichomes functioning as a resistance mechanism with consequences for herbivore choice, performance, and distribution.  相似文献   
9.
Changes in chromatin structure regulate gene expression and genome maintenance. Molecules that bind to the nucleosome, the complex of DNA and histone proteins, are key modulators of chromatin structure. Previous work indicated that cholesterol, a ubiquitous cellular lipid, may bind to chromatin in vivo, suggesting a potential function for lipids in modulating chromatin architecture. However, the molecular mechanisms of cholesterol's action on chromatin structure have remained unclear. Here, we explored the biophysical impact of cholesterol on nucleosome and chromatin fibers reconstituted in vitro and characterized in silico the cholesterol binding to the nucleosome. Our findings support that cholesterol assists 10 and 30 nm chromatin formation and induces folding of long chromatin fibers as a result of direct interaction of the cholesterol to six nucleosomal binding sites.  相似文献   
10.
Obesity causes serious medical complications and impairs quality of life. Moreover, in older persons, obesity can exacerbate the age‐related decline in physical function and lead to frailty. However, appropriate treatment for obesity in older persons is controversial because of the reduction in relative health risks associated with increasing body mass index and the concern that weight loss could have potential harmful effects in the older population. This joint position statement from the American Society for Nutrition and NAASO, The Obesity Society reviews the clinical issues related to obesity in older persons and provides health professionals with appropriate weight‐management guidelines for obese older patients. The current data show that weight‐loss therapy improves physical function, quality of life, and the medical complications associated with obesity in older persons. Therefore, weight‐loss therapy that minimizes muscle and bone losses is recommended for older persons who are obese and who have functional impairments or medical complications that can benefit from weight loss.  相似文献   
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