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31.
Factors influencing family physicians to enter rural practice: Does rural or urban background make a difference?
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The activation of phospholipase A2 is believed to have an important role in the inflammatory process owing to its induction of eicosanoids, platelet activating factor, and other mediators. Soluble phospholipase A2 has been associated with exudates in different inflammatory conditions. In this review the general physiology and control of this enzyme and, in particular, the most recent findings on human synovial fluid phospholipase A2s are discussed. 相似文献
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阴茎勃起神经再生模型和机制的研究 总被引:1,自引:0,他引:1
探明神经性勃起功能障碍(NED)的分子生物学机制以期对该类疾病进行神经调控干预,是男科学研究的当务之急。本文回顾了急性神经损伤、前列腺癌、糖尿病和帕金森病所致的NED的研究进展。通过利用大鼠阴茎勃起神经的盆腔大神经节(MPG),在体外构建一个三维培养体系来研究各种生长因子和细胞信号通路对神经再生的影响。体外结果表明脑源性神经生长因子(BDNF)通过JAK/STAT信号通路可显著促进NED的恢复,并在体内证实了该效应。因此,通过调控JAK/STAT信号通路来达到神经调控干预措施预防治疗神经性勃起功能障碍成为可能。 相似文献
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J Chhabra Y-Z Li H Alkhouri A E Blake Q Ge C L Armour J M Hughes 《The European respiratory journal》2007,29(5):861-870
Degranulating mast cells are increased in the airway smooth muscle (ASM) of asthmatics, where they may influence ASM function. The aim of the present study was to determine whether histamine and tryptase modulate ASM cell granulocyte-macrophage colony-stimulating factor (GM-CSF) and RANTES (regulated on activation, normal T-cell expressed and secreted) release and also to examine which receptors are involved in this release. Confluent, quiescent ASM cells from asthmatic and nonasthmatic donors were treated with histamine (1 microM-100 microM) with and without histamine receptor antagonist pre-treatment, or the protease-activated receptor (PAR)-2 agonists tryptase (0.5-5 nM) and SLIGKV (100 and 400 microM). The cells were then stimulated with interleukin (IL)-1beta and/or tumour necrosis factor (TNF)-alpha (10 ng.mL(-1)) or left unstimulated for 24 h. Release of GM-CSF and RANTES was determined by ELISA and prostaglandin (PG)E(2) measured by enzyme immunoassay. Neither histamine nor tryptase induced ASM GM-CSF or RANTES secretion. However, histamine increased IL-1beta-induced GM-CSF release and markedly reduced TNF-alpha-induced RANTES release by both asthmatic and nonasthmatic cells to a similar extent, but did not modulate PGE(2) release. All changes involved activation of the histamine H1 receptor as they were partially or fully blocked by chlorpheniramine, but not ranitidine. Tryptase, via its proteolytic activity, also potentiated GM-CSF, but not RANTES, release from asthmatic and nonasthmatic ASM cells induced by both cytokines. PAR-2 involvement in the tryptase potentiation was unlikely because SLIGKV had no effect. In conclusion, mast cells, through histamine and tryptase, may locally modulate airway smooth muscle-induced inflammation in asthma. 相似文献
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Adam J. Singer MD Steve A. McClain MD Alexander Romanov DVM Jean Rooney BS Tom Zimmerman DVM 《Academic emergency medicine》2007,14(12):1125-1129
Objectives Cutaneous burns are dynamic injuries with a central zone of necrosis surrounded by a zone of ischemia. Conversion of this ischemic zone to full necrosis over the days following injury is due in part to highly reactive oxygen radicals. Curcumin is a component of the Oriental spice turmeric that has been shown to have antioxidant and antiapoptotic properties. The authors hypothesized that treatment of burns with curcumin would reduce the conversion of the ischemic zone to full necrosis. Methods This was a randomized controlled experiment. Twenty Sprague‐Dawley rats were used. Two burns were created on each animal's dorsum using a brass comb with four rectangular prongs preheated in boiling water and applied for 30 seconds, resulting in four rectangular 10 × 20–mm full‐thickness burns separated by three 5 × 20–mm unburned interspaces (zone of ischemia). Animals were randomized to curcumin or vehicle by oral gavage 30 minutes before injury and at 24, 48, and 72 hours after injury. Wounds were observed at one, two, and three days after injury for visual evidence of necrosis in the unburned interspaces. Full‐thickness biopsy specimens from the interspaces were evaluated with hematoxylin and eosin staining seven days after injury for evidence of necrosis. The percentage of interspaces that progressed to necrosis was compared with chi‐square tests. Results Forty comb burns with 120 unburned interspaces were created, evenly distributed between curcumin and vehicle alone. The percentage of interspaces that progressed to full‐thickness necrosis at one, two, three, and seven days after injury in the curcumin and vehicle groups were 30% versus 63% (p = 0.003), 30% versus 70% (p < 0.001), 63% versus 95% (p = 0.02), and 63% versus 95% (p = 0.02), respectively. Conclusions Pretreatment of rats with oral curcumin followed by once‐daily oral treatment for three days reduced the percentage of unburned skin interspaces that progressed to full necrosis. 相似文献
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Government reform of the NHS in the UK has sought to increase the involvement of doctors (clinicians) in hospital management. Using frameworks from the psychological contract and organisational misbehaviour literatures, this paper examines the processes involved when clinicians assume management roles. This literature seeks to explain breaches to expectations regarding prior agreements with management and subsequent actions of 'getting even' as a result of breaches to the employment relationship. A qualitative methodology using interviews was undertaken, which identified two distinct groups of clinician-manager. Investors actively pursued a management opportunity as an alternative to clinical medicine, whilst reluctants tended to assume a management role to protect particular specialities from outside influence or from those they thought would be inappropriate clinician-managers. Investors and reluctants often had very little prior experience of management and managers and had problems reconciling their dual clinician-management role. Poor relationships with hospital managers who often had no understanding of their dual responsibilities led to tensions and conflict, which questions continued developments in this important area of UK health policy. Suggestions for improving this process are outlined. 相似文献
39.
John Walls Dr Nick Pidgeon Andrew Weyman Tom Horlick-Jones 《Health, risk & society》2004,6(2):133-150
The binary opposition of trusting or not trusting is inadequate to understand the often ambiguous and contradictory ideas people possess about risk regulators, particularly when knowledge and experience of such institutions is limited. The paper reports qualitative and quantitative data from a major study of public perceptions (n?=?30 focus groups) of UK risk regulators. We compare the complex and widely different ‘trust profiles’ of two regulatory organisations which are institutionally related (the Health and Safety Executive and the Railways Inspectorate) but very separate in the minds of our participants. The paper develops the notion of critical trust to interrogate the various ways in which people make sense of such organisations, as well as discussing the modes of reasoning that people deploy. The paper argues that views of participants are the outcome of a reconciliation of diverse perceptions concerning the role of the organisation, structural factors and the nature of the regulated risk. 相似文献
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