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991.

Background

Social integration predicts morbidity and mortality, but its relationships with specific health behaviors that could explain this relationship, such as physical activity, have not been established. Additionally, studies associating social integration with health have not distinguished between sources of social contact (family vs. friends), which could be differentially related to health.

Purpose

The purpose of this study was to examine the association between social integration and physical activity and to explore differences in family and friend social integration.

Method

Data came from the 2001 wave of the National Health Interview Survey. Adult participants (N?=?33,326) indicated levels of social integration by reporting whether they had seen and/or called friends and/or family in the past 2 weeks and also reported their weekly minutes of physical activity. Logistic regression was used to determine odds of meeting physical activity (PA) guidelines (≥150 min/week) and odds of inactivity (0 min/week) based on levels of social integration.

Results

Greater integration predicted higher odds of meeting PA guidelines and lower odds of inactivity after controlling for sociodemographic variables. This association was stronger and dose-dependent for integration with friends, whereas moderate family contact predicted greater activity than high levels of family contact.

Conclusion

Those who are more socially integrated, particularly with friends rather than family, are also more physically active, which could partially explain the link between social integration and morbidity and mortality. Future studies examining this association should distinguish between sources of integration and explore why and how contact with friends vs. family is differentially associated with health behaviors.  相似文献   
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Livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) of the clonal complex (CC) 398 became primarily known as colonizers of livestock animals. In the past few years, they have been increasingly introduced into hospitals with subsequent emergence of human infections. However, the (re-)adaptation to the human host is only incompletely understood. This study aimed to assess virulence properties of LA-MRSA CC398 by functional modeling of infection and colonization processes. A selection of 15 human LA-MRSA CC398 isolates and 11 pig-colonizing isolates were characterized regarding their virulence capacities and compared with human isolates of hospital-acquired (HA)-MRSA (CC5, CC22 and CC45) and community-associated (CA)-MRSA (CC8, CC30 and CC80) clonal lineages. Our investigations demonstrated that LA-MRSA CC398 adhered less efficient to human cells and human/bovine plasma fibronectin than CA-MRSA and HA-MRSA isolates. In contrast, the LA-MRSA CC398 isolates revealed a high cytotoxic potential comparable to certain CA-MRSA. Comparing the most prevalent LA-MRSA CC398 spa types (t011, t034, t108), isolates associated with spa t108 showed an increased adhesive and invasive potential paired with an increased ability to evade phagocytosis. The results underline both the pathogenic potential of LA-MRSA in general and the heterogeneity within the CC398 clade regarding the virulence characteristics of CC398 subpopulations. Assuming an ongoing (re-)adaptation to the human host combined with a huge reservoir of LA-MRSA CC398 in livestock and constant zoonotic transmission, the LA-MRSA CC398 lineage has the potential to pose a serious threat to human health.  相似文献   
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Neuroendocrine differentiation of tumor tissue has been recognized as an important prerequisite for new targeted therapies. To evaluate the suitability of colorectal cancer (CRC) tissue for these treatment approaches and to find a possible link to pretherapeutic conditions of other targeted strategies, we compared neuroendocrine differentiation and KRAS/NRAS/BRAF/PIK3CA/TP53 mutational status in primary and metastatic CRC. Immunohistochemical expression analysis of neuroendocrine markers chromogranin A and synaptophysin was performed on archival CRC tissue, comprising 116 primary tumors, 258 lymph node metastases and 72 distant metastases from 115 patients. All CRC samples but 30 distant metastases were subjected to mutation analysis of KRAS, NRAS, BRAF, PIK3CA, and TP53. Neuroendocrine marker expression was found significantly less frequently in lymph node metastases compared to primary tumors and distant metastases (20%, 31%, 28%, respectively, P = 0.044). KRAS mutation rates increased significantly from primary tumors to lymph node metastases and distant metastases within the neuroendocrine negative CRC group (44%, 53%, 64%, respectively, P = 0.042). Neuroendocrine differentiation was significantly less concordant than KRAS/NRAS/BRAF/PIK3CA/TP53 mutational status in primary tumor/lymph node metastases pairs (65% versus 88%-99%; P < 0.0001) and primary tumor/distant metastases pairs (64% versus 83%-100%; P = 0.027 and P < 0.0001, respectively). According to these data, therapeutic targeting of neuroendocrine tumor cells can be considered only for a subset of CRC patients and biopsies from the metastatic site should be used to guide therapy. A possible importance of lacking neuroendocrine differentiation for progression of KRAS mutant CRC should be further investigated.  相似文献   
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Objective

The main objective was to gain a deeper understanding of how medical students perceive and experience learning from gynecological teaching women (GTW) instead of physicians in their first pelvic examination. A second aim was to describe how the women experience their roles as GTW.

Methods

Data were collected from individual interviews with 24 medical students from a medical school in Sweden and with 5 GTW. Discourse analysis was performed to acquire a deeper understanding of the informants’ experiences and to understand social interactions.

Results

Five themes revealed in the medical students’ experiences: “Hoping that anxiety will be replaced with security,” “Meeting as equals creates a sense of calm,” “Succeeding creates a sense of security for the future,” “Wanting but not having the opportunity to learn more,” and “Feeling relieved and grateful.” One theme revealed in the GTW experiences: “Hoping to relate in a trustworthy way.”

Conclusion

To replace physicians with GTW may facilitate the learning process and may also help medical students improve their communicative skills. Using GTW will hopefully further improve students’ basic medical examination techniques and physician–patient relationships.

Practice implications

Since GTW seems to increase self-confidence and skills of medical students performing their first pelvic examination we recommend that the use of GTW is considered in the training of medical students.  相似文献   
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