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排序方式: 共有622条查询结果,搜索用时 225 毫秒
101.
Challis MJ Gaston P Wilson K Jull GA Crawford R 《The Journal of bone and joint surgery. British volume》2006,88(3):411-415
The aim of this randomised, controlled in vivo study in an ovine model was to investigate the effect of cyclic pneumatic pressure on fracture healing. We performed a transverse osteotomy of the right radius in 37 sheep. They were randomised to a control group or a treatment group where they received cyclic loading of the osteotomy by the application of a pressure cuff around the muscles of the proximal forelimb. Sheep from both groups were killed at four or six weeks. Radiography, ultrasonography, biomechanical testing and histomorphometry were used to assess the differences between the groups. The area of periosteal callus, peak torsional strength, fracture stiffness, energy absorbed over the first 10 degrees of torsion and histomorphometric analysis all showed that the osteotomies treated with the cyclic pneumatic pressure at four weeks were not significantly different from the control osteotomies at six weeks. 相似文献
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A case of cavernous hemangioma of the bladder is presented and its endoscopic appearance is illustrated. A scan utilizing technetium-99-labeled albumin has been found valuable in determining the extent of the lesion. 相似文献
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The GMC's publication The New Doctor ( GMC 1997 ) outlines an approach for the education of Pre-registration House Officers using designated educational supervisors. In order to establish appropriate means of training consultants to undertake this role, the Centre for Postgraduate and Continuing Medical Education at the Queens Medical Centre, Nottingham undertook a needs analysis. This consisted of a series of individual interviews with directors of postgraduate education in the mid-Trent region, four focus groups with consultants, and two dissemination workshops. The findings from the research have led to the development of a modular educational programme, based on the perceived needs and optimum structure indicated by the participants in the research process. 相似文献
108.
Expression of extracellular matrix metalloproteinase inducer in human placenta and fetal membranes at term labor 总被引:4,自引:0,他引:4
Li W Alfaidy N Challis JR 《The Journal of clinical endocrinology and metabolism》2004,89(6):2897-2904
Matrix metalloproteinases (MMPs) are the main mediators of extracellular matrix (ECM) degradation during human parturition. However, the mechanisms involved in regulation of MMP production during parturition remain poorly understood. Recently, an extracellular matrix metalloproteinase inducer (EMMPRIN) has been shown to play a key role, as a local regulator, in stimulating MMP production in cancer systems. Whether EMMPRIN is expressed and stimulates MMP production in human placenta and fetal membranes is presently unknown. In this study, we investigated the expression of EMMPRIN at the levels of mRNA and protein in human term placenta and fetal membranes with or without labor. Western blot analysis showed that EMMPRIN protein was detected in term placenta and fetal membranes at two molecular masses of 40 and 65 kDa (glycosylated protein) and one of approximately 30 kDa (nonglycosylated protein). The ratio of 65 kDa EMMPRIN to total EMMPRIN significantly increased (P < 0.05) in term labor chorio-decidua and amnion compared with nonlabor chorio-decidua and amnion. Immunohistochemical analysis revealed that EMMPRIN was expressed in placental syncytiotrophoblast, amniotic epithelial cells, trophoblast cells of chorion laeve, and decidua parietalis. EMMPRIN was also detected at the mRNA level using RT-PCR in cultured placental syncytiotrophoblast, amniotic epithelial cells, and chorionic trophoblast cells. We conclude that human placenta and fetal membranes express EMMPRIN, with the potential to stimulate MMP production, thereby facilitating fetal membrane rupture and leading to detachment of the placenta and fetal membranes from the maternal uterus at the time of parturition. 相似文献
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Mei Yin Wong Katrina A. Andrews Benjamin G. Challis Soo‐Mi Park Carlo L. Acerini Eamonn R. Maher Ruth T. Casey 《Clinical endocrinology》2019,90(4):499-505
The succinate dehydrogenase (SDH) enzyme complex functions as a key enzyme coupling the oxidation of succinate to fumarate in the citric acid cycle. Inactivation of this enzyme complex results in the cellular accumulation of the oncometabolite succinate, which is postulated to be a key driver in tumorigenesis. Succinate accumulation inhibits 2‐oxoglutarate‐dependent dioxygenases, including DNA and histone demethylase enzymes and hypoxic gene response regulators. Biallelic inactivation (typically resulting from one inherited and one somatic event) at one of the four genes encoding the SDH complex (SDHA/B/C/D) is the most common cause for SDH deficient (dSDH) tumours. Germline mutations in the SDHx genes predispose to a spectrum of tumours including phaeochromocytoma and paraganglioma (PPGL), wild type gastrointestinal stromal tumours (wtGIST) and, less commonly, renal cell carcinoma and pituitary tumours. Furthermore, mutations in the SDHx genes, particularly SDHB, predispose to a higher risk of malignant PPGL, which is associated with a 5‐year mortality of 50%. There is general agreement that biochemical and imaging surveillance should be offered to asymptomatic carriers of SDHx gene mutations in the expectation that this will reduce the morbidity and mortality associated with dSDH tumours. However, there is no consensus on when and how surveillance should be performed in children and young adults. Here, we address the question: “What age should clinical, biochemical and radiological surveillance for PPGL be initiated in paediatric SDHx mutation carriers?”. 相似文献