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排序方式: 共有9045条查询结果,搜索用时 15 毫秒
991.
Nutritional Risk in Emergency‐2017: A New Simplified Proposal for a Nutrition Screening Tool 下载免费PDF全文
992.
Essau CA 《Psychosomatics》2007,48(6):502-509
The author examined the course of somatoform disorders in non-referred adolescents. Somatoform disorders were coded from DSM-IV criteria, using the computerized Munich (Germany) version of the Composite International Diagnostic Interview. About 35.9% of the adolescents with somatoform disorders at the index investigation continued to have the same disorders at the follow-up investigation: 26.7% had anxiety, 17.1% had depression, 22% had substance-use disorders, and 53.7% had no psychiatric disorders. Factors related to the chronicity of somatoform disorders included gender, comorbid depressive disorders, parental psychiatric disorders, and negative life events. Somatoform disorders showed a heterogeneous pattern of course. 相似文献
993.
Fibrin has been long used as an effective scaffolding material to grow a variety of cells and tissue constructs. It has been utilized mainly as a hydrogel in varying concentrations to provide an environment in which suspended cells work to rearrange the fibers and lay down their own extracellular matrix. For these fibrin hydrogels to be useful in many tissue-engineering applications, the gels must be cultured for long periods of time in order to increase their mechanical strength to the levels of native tissues. High concentrations of fibrinogen increase the mechanical strength of fibrin hydrogels, but at the same time reduce the ability of cells within the scaffold to spread and survive. We present a method to create a microporous, nanofibriliar fibrin scaffold that has controllable pore size, porosity, and microstructure for applications in tissue engineering. Fibrin has numerous advantages as a scaffolding material as it is normally used by the body as temporary scaffolding for tissue regeneration and healing, and can be autologously sourced. We present here a scaffolding process which enhances the mechanical properties of the fibrin hydrogel by forming it surrounding poly(methyl-methacrylate) beads, then removing the beads with acetone to form an interconnected microporous network. The acetone serves the dual purpose of precipitating and fixing the fibrinogen-based scaffolds as well as adding strength to the network during polymer bead removal. Effects of fibrinogen concentration and time in acetone were examined as well as polymerization with thrombin. A natural crosslinker, genipin, was also used to add strength to the scaffolds, producing a Young's modulus of up to 184+/-5 kPa after 36 h of reaction. Using these methods we were able to produce microporous fibrin scaffolds that support cell growth and have mechanical properties similar to many native tissues. 相似文献
994.
Mantovani A Garlanda C Locati M Rodriguez TV Feo SG Savino B Vecchi A 《Autoimmunity reviews》2007,7(1):8-11
Tuning is a key aspect of inflammatory reaction essential in homeostasis and pathology. An emerging mechanism for negative regulation of proinflammatory cytokines is based on non-signaling IL-1/TLR receptors and chemokine receptors competing with signaling receptors for ligand binding and sustaining ligand internalization and degradation. Biological activities of IL-1R/TLR receptors are under control of membrane-bound binding molecules lacking the signaling domain, soluble receptor antagonists, and intracellular signaling inhibitors. The chemokine system includes at least three 'silent' receptors with distinct specificity and tissue distribution. D6 is the best characterized representative member of this class of negative regulators, binds most inflammatory, but not homeostatic, CC chemokines and shuttles in a ligand-independent way from the plasma membrane to endocytic compartments where chemokines are targeted to degradation. In vitro and in vivo evidence, including results with gene targeted mice, is consistent with the view that these non-signaling receptors for proinflammatory cytokines possess unique functional and structural features which make them ideally adapted to act as a decoy and scavenger receptors, with a non redundant role in dampening tissue inflammation and tuning draining lymph nodes reactivity. 相似文献
995.
Ho CY Tang NL Yeung AK Lau AK Hui J Lo AW 《Journal of molecular medicine (Berlin, Germany)》2007,85(4):351-360
Defects in the multimeric enzyme, UDP-N-acetylglucosamine:lysosomal enzyme N-acetylglucosamine-1-phosphotransferase (GNPT), result in the diseases of mucolipidosis (ML). This enzyme generates the mannose 6-phosphate residues on newly synthesized lysosomal enzymes for the efficient receptor-mediated transport to lysosomes. The enzyme contains alpha/beta and gamma subunits. Mutations in the alpha/beta subunit result in the classical ML II and IIIA, while defects in the gamma subunit results in the clinically milder ML IIIC. I-cells, a distinct histological feature characterized by the presence of abnormal cytoplasmic vacuoles, are detected in many cell types, most noticeably, in ML II patients. In this study, we investigated the interactions of the alpha/beta and gamma subunits in the pathogenesis of I-cells. We noted low and deranged alpha/beta subunit expressions in human mucolipidosis cell lines. Unexpectedly, high gamma subunit expressions were also observed. In normal mouse fibroblasts, when alpha/beta subunit was suppressed, abnormal cytoplasmic vacuoles were induced, and up-regulation of the gamma subunit was also observed. On the other hand, suppressing the gamma subunit resulted in biphasic responses of the alpha/beta subunit, while abnormal cytoplasmic vacuoles were not formed, regardless of the expression levels of the alpha/beta subunit. Our data suggest reciprocal feedback mechanisms between alpha/beta and the gamma subunits. A fine balance of the expressions of these subunits may play an important role in the formation of I-cells in this group of lysosomal storage disorders. 相似文献
996.
Cecilia Buccheri Alessandra Casuccio Santo Giammanco Marco Giammanco Maurizio La Guardia Caterina Mammina 《BMC health services research》2007,7(1):45
Background
Food hygiene in hospital poses peculiar problems, particularly given the presence of patients who could be more vulnerable than healthy subjects to microbiological and nutritional risks. Moreover, in nosocomial outbreaks of infectious intestinal disease, the mortality risk has been proved to be significantly higher than the community outbreaks and highest for foodborne outbreaks. On the other hand, the common involvement in the role of food handlers of nurses or domestic staff, not specifically trained about food hygiene and HACCP, may represent a further cause of concern. 相似文献997.
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999.
Bianchi FT Reisen CA Zea MC Poppen PJ Shedlin MG Penha MM 《Culture, health & sexuality》2007,9(5):505-518
Key informant interviews, in-depth interviews and focus groups were conducted to examine ways in which social context influenced the behavior of Brazilian, Colombian and Dominican men who have sex with men. First, we investigated how the social context in the home country affected motivation for migration. Findings suggest that Latino men who have sex with men frequently reported coming to the USA to escape homo-negativity and to achieve greater sexual freedom. The study also examined how the social context encountered in the early years after migration shaped sexual behavior and risk. A majority of the participants reported easy access to sex partners and frequent sexual encounters. The anonymity of living in a gay epicentre such as New York City, often without social connections from the past, was experienced as liberating and conducive to sexual exploration. Moreover, sex in public venues, such as parks and sex cabins, was readily available to those who do not speak English. The tendency to engage in high levels of sexual activity during the early period after arrival in New York City was particularly evident among younger men. Implications for future programme development are discussed alongside prevention efforts targeting migrants during this critical period. 相似文献
1000.