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1.
The objective of this 2nd phase of a 2-year study among female nurses was to provide further empirical validation of the demands-control and social support model. The association of job strain with psychological problems and the potential modifying role of social support at work were examined. A questionnaire was sent at the workplace to 1,741 nurses. The same associations were found between psychological demands, decision latitude, and a combination of the 2 with psychological distress and emotional exhaustion for current exposure and for cumulative exposure. Social support had a direct effect on these psychological symptoms but did not modify their association with job strain. Longitudinal and prospective data are needed to study the occurrence and persistence of health problems when exposure is maintained or retrieved. 相似文献
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A. Baillot M. Asselin E. Comeau A. Méziat-Burdin M.-F. Langlois 《Obesity surgery》2013,23(11):1826-1834
Background
Over 70 % of people who undergo bariatric surgery (BS) develop excess skin (ES). The physical and psychosocial consequences of ES may become a barrier to the practice of physical activity (PA), which is highly recommended to optimize the results of BS. The purpose of this study was to evaluate the impact of ES on the practice of PA in women who have undergone BS.Methods
Questionnaires administered to 26 women having undergone BS 2?±?0.2 years before (BMI?=?29.1?±?0.8 kg/m2) evaluated the impacts of ES, the practice of PA, physical self-perception, and physical exercise beliefs. We also used the 6-min walking test and muscular endurance tests to evaluate physical fitness and photographs with anatomical markers to quantify ES.Results
Of the women, 76.9 % declared mobility limitations due to ES during the practice of PA and 45.2 % stated avoiding PA because of ES which caused flapping and unwelcome stares from others. The women who stated that they avoided PA because of ES had significantly lower physical self-perception and physical fitness and reported experiencing more embarrassment during PA despite no significant difference in the magnitude of ES (p?=?0.06), BMI, daily life inconveniences, and energy expenditure compared to those women who did not avoid PA.Conclusion
Although ES after BS is a barrier to the practice of PA for some women, it does not in itself prevent the regular practice of PA. The main reason women with ES avoid PA seems to have less to do with the magnitude of ES itself and more with psychosocial inconveniences. 相似文献5.
Among the most numerous objects in the biosphere, phages show enormous diversity in morphology and genetic content. We have sequenced 7 T4-like phages and compared their genome architecture. All seven phages share a core genome with T4 that is interrupted by several hyperplastic regions (HPRs) where most of their divergence occurs. The core primarily includes homologues of essential T4 genes, such as the virion structure and DNA replication genes. In contrast, the HPRs contain mostly novel genes of unknown function and origin. A few of the HPR genes that can be assigned putative functions, such as a series of novel Internal Proteins, are implicated in phage adaptation to the host. Thus, the T4-like genome appears to be partitioned into discrete segments that fulfil different functions and behave differently in evolution. Such partitioning may be critical for these large and complex phages to maintain their flexibility, while simultaneously allowing them to conserve their highly successful virion design and mode of replication. 相似文献
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Ultrasound scan showed some degree of placenta previa in 503 patients. Of this group, 5.6% (28) had clinically significant bleeding or documented placenta previa at delivery. A scoring system based on placental localization was not successful in predicting who was at high risk for bleeding. However, the likelihood of clinically excessive bleeding did significantly increase if the placenta previa was noted after 30 weeks' gestation. The study did not find a greater incidence of small-for-gestational-age babies in women with low-lying placentas. 相似文献
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Petrella T Comeau MR Maynadié M Couillault G De Muret A Maliszewski CR Dalac S Durlach A Galibert L 《The American journal of surgical pathology》2002,26(7):852-862
In 1999, we reported seven cases of an unusual hematologic malignancy with primary cutaneous presentation that appeared as a distinct clinicopathologic entity characterized by medium-sized tumor cells with a peculiar CD3- CD4+ CD56+ CD43+ HLA-DR+ cell surface phenotype. Because the origin of tumor cells was not clear and they exhibited a nonlineage-specific phenotype, we hypothesized that such tumors likely originated from hematologic-myeloid precursor cells and were tentatively assigned the designation "agranular CD4+ CD56+ hematodermic neoplasms." In the present study we report 14 cases (seven already reported and seven additional cases) of these tumors, and simultaneously we present now a rare population of cells that we have identified in the peripheral blood of healthy volunteers treated with Flt3 ligand. These cells express all the characteristic markers of CD4+ CD56+ hematodermic neoplasms. This population appears to be related to plasmacytoid monocytes because they also expressed CD68 and bright levels of CD123. To confirm the relationship between these normal cells and CD4+ CD56+ hematodermic neoplasms, we conducted an extensive comparative phenotypic study. Results show that these two cell types are indeed related because they share many phenotypic features, including the presence of CD4, CD56, CD43, CD68, and HLA-DR and the absence of other T, B, NK, or myelomonocytic markers. More importantly, we found that the bright expression of CD123 by immunohistochemistry is a distinctive characteristic of CD4+ CD56+ hematodermic neoplasms because all (n = 14) cases expressed this marker, whereas only two specimens in a control panel comprising 30 samples of related tumors expressed comparable levels of CD123. We therefore propose that oncogenic transformation of NCAM-expressing plasmacytoid monocyte-like cells may lead to "agranular CD4+ CD56+ hematodermic neoplasm." 相似文献
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Unlike mammalian plasma pseudocholinesterases where the I50 values for dichlorvox are 100-fold higher than those for diisopropylfluorophosphate, mammalian hepatic aliesterases were inhibited to the same extent by concentrations of these two agents which did not differ more than 4-fold within species. Feline hepatic aliesterases were an exception in that dichlorvos was 100 times less potent than diisopropylfluorophosphate. 相似文献