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排序方式: 共有1421条查询结果,搜索用时 78 毫秒
31.
David G. Fuentes Rachel R. Ogden Ann Ryan-Haddad Aimee F. Strang 《American journal of pharmaceutical education》2015,79(3)
During our time in the 2013 Academic Leadership Fellows Program, we explored what it takes to achieve life balance through a framework presented in a Harvard Business Review article. In this Statement, we describe 5 different areas from the article that provide infrastructure for reflecting on how we have learned to approach life balance in academia. We also provide brief messages based on this reading and others to help academics’ pursuit of life balance. 相似文献
32.
Geoffrey M. Curtin Sandra I. Sulsky Cynthia Van Landingham Kristin M. Marano Monica J. Graves Michael W. Ogden James E. Swauger 《Regulatory toxicology and pharmacology : RTP》2014
There are no large-scale, carefully designed cohort studies that provide evidence on whether menthol cigarette use is associated with a differential risk of initiating and/or progressing to increased smoking. However, questions of whether current menthol cigarette smokers initiated smoking at a younger age or are more likely to have transitioned from non-daily to daily cigarette use compared to non-menthol smokers can be addressed using cross-sectional data from U.S. government surveys. Analyses of nationally representative samples of adult and youth smokers indicate that current menthol cigarette use is not associated with an earlier age of having initiated smoking or greater likelihood of being a daily versus non-daily smoker. Some surveys likewise provide information on cigarette type preference (menthol versus non-menthol) among youth at different stages or trajectories of smoking, based on number of days smoked during the past month and/or cigarettes smoked per day. Prevalence of menthol cigarette use does not appear to differ among new, less experienced youth smokers compared to established youth smokers. While there are limitations with regard to inferences that can be drawn from cross-sectional analyses, these data do not suggest any adverse effects for menthol cigarettes on measures of initiation and progression to increased smoking. 相似文献
33.
34.
The present study examined the experience of vaginismus in 89 sufferers and ex-sufferers using quantitative and qualitative methodologies. The results provide insights into the effects of vaginismus on the sufferers' self perception and on their relationships with important others. It is suggested that vaginismus should not be regarded as a psychosexual problem but as a psychosocial experience in which defences have been created to protect the self, and that the vaginal spasm is only one of the many effects of this defence. 相似文献
35.
Federico F. Trigo Takeshi Sakaba David Ogden Alain Marty 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(44):18138-18143
To distinguish between different models of vesicular release in brain synapses, it is necessary to know the number of vesicles of transmitter that can be released immediately at individual synapses by a high-calcium stimulus, the readily releasable pool (RRP). We used direct stimulation by calcium uncaging at identified, single-site inhibitory synapses to investigate the statistics of vesicular release and the size of the RRP. Vesicular release, detected as quantal responses in the postsynaptic neuron, showed an unexpected stochastic variation in the number of quanta from stimulus to stimulus at high intracellular calcium, with a mean of 1.9 per stimulus and a maximum of three or four. The results provide direct measurement of the RRP at single synaptic sites. They are consistent with models in which release proceeds from a small number of vesicle docking sites with an average occupancy around 0.7. 相似文献
36.
The potential use of single nucleotide polymorphism markers (SNPs) in conservation genetics is widely recognized; however, methods for discovering large numbers of SNPs typically rely on relatively expensive, genome-wide, species-specific research projects which limits their development in many taxa. Here we describe the use of high-density SNP genotyping arrays designed for cattle to discover SNPs in two antelope species. From a total of 54,001 SNP markers on the array, the analysis yielded 148 polymorphic markers in the scimitar-horned oryx and 149 in the Arabian oryx. The results represent a first step toward developing SNP marker panels for ongoing projects on each species. As high density genotyping arrays become available for an increasing number of model species, this approach has the potential to generate SNP markers, rapidly and affordably, in a broad range of species for conservation genetic research. 相似文献
37.
Peracchi M; Toschi V; Bamonti-Catena F; Lombardi L; Bareggi B; Cortelezzi A; Colombi M; Maiolo AT; Polli EE 《Blood》1987,69(6):1613-1616
To verify the clinical usefulness of extracellular cyclic nucleotide determination as a tumor marker, plasma cyclic AMP (cAMP) and cyclic GMP (cGMP) levels were measured in 70 normal subjects and 173 acute leukemia patients studied in different stages of their disease. Mean plasma cAMP levels were similar in leukemic and normal subjects, although in 48 patients in the active stage of the disease, first diagnosis, or relapse, the cAMP values were below the normal range, and most of these patients failed to respond to chemotherapy. Plasma cGMP levels were markedly elevated in untreated patients, normalized in all patients who attained complete remission, and increased promptly to pretreatment values in patients who relapsed, suggesting that their determination may be useful to monitor the patients' response to treatment. 相似文献
38.
Jane Ogden 《European eating disorders review》1995,3(4):228-241
The present study examined the cognitive and motivational consequences of dieting behaviour. Twenty-three dieters completed rating scales of mood and cognitive and motivational states three times a week and profile questionnaires at the beginning and end of a six-week period of caloric restriction. A control group of 18 non-dieters were also assessed for a comparative period. The results showed several profile differences between the two groups with the dieters reporting lower eating self-efficacy and greater body dissatisfaction at the start of the period of caloric restriction. There were some differential changes over the period of the diet, with the dieters showing increases in both depression and loss of control, a decrease in hunger and a temporary increase in the preoccupation with food compared to the non-dieters. The implications of the results are analysed in relation to both the long-term and short-term effects of caloric restraint. Their relevance to recent theories of disturbances in eating behaviour are discussed. 相似文献
39.
Carol Anne Ogden Robert Kowalewski YuFeng Peng Vivianne Montenegro Keith B. Elkon 《Autoimmunity》2013,46(4):259-264
A variety of complement components have been detected on apoptotic cells and proposed to facilitate recognition and/or ingestion by phagocytes. The triggers for complement activation remain uncertain. To determine the role of IgM in classical pathway activation and clearance of apoptotic cells in vitro and in vivo, we quantified these parameters in mice deficient in serum IgM (sIgM). Phagocytosis by bone marrow-derived macrophages of apoptotic cells incubated with serum deficient in sIgM was markedly reduced, similar to apoptotic cells incubated with C1q deficient serum in vitro. Similarly, intraperitoneal clearance of apoptotic cells and cellular C3 deposition were significantly reduced in mice deficient in sIgM compared to wild-type mice. Clearance and C3 deposition were reconstituted by addback of IgM. In mice deficient in both sIgM and C1q, addback of both serum factors was required for restoration of clearance. These findings indicate that, on a quantitative basis, sIgM is a potent factor required for intraperitoneal phagocytosis of apoptotic cells, and further demonstrate that IgM and C1q work in concert to activate complement, resulting in C3 deposition on the apoptotic cell surface and ultimately, efficient clearance of the apoptotic cell by macrophages. 相似文献
40.
David S. Freedman Jack Wang Cynthia L. Ogden John C. Thornton Zuguo Mei Richard N. Pierson 《Annals of human biology》2013,40(2):183-194
Background: Although the body mass index (BMI, kg?m?2) is widely used as a measure of adiposity, it is a measure of excess weight, rather than excess body fat. It has been suggested that skinfold thicknesses be measured among overweight children to confirm the presence of excess adiposity.Objective: The present study examined the additional information provided by skinfold thicknesses on body fatness, beyond that conveyed by BMI-for-age, among healthy 5- to 18-years old (n?=?1196).Methods and procedures: Total body dual-energy X-ray absorptiometry (DXA) provided estimates of % body fat, and the sum of two skinfolds (triceps and subscapular) was used as an indicator of the overall skinfold thickness.Results: As assessed by the multiple R2s and the residuals of various regression models, information on the skinfold sum significantly (?p?<?0.001) improved the prediction of body fatness beyond that obtained with BMI-for-age. For example, the use of the skinfold sum, in addition to BMI-for-age, increased the multiple R2s for predicting % body fat from 0.81 to 0.90 (boys), and from 0.82 to 0.89 (girls). The use of the skinfold sum also reduced the overall prediction errors (absolute value of the residuals) for % body fat by 20–30%, but these reductions varied substantially by BMI-for-age. Among overweight children, defined by a BMI-for-age ≥95th percentile, the skinfold sum reduced the predication errors for % body fat by only 7–9%.Conclusions: Although skinfold thicknesses, when used in addition to BMI-for-age, can substantially improve the estimation of body fatness, the improvement among overweight children is small. 相似文献