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排序方式: 共有896条查询结果,搜索用时 15 毫秒
101.
BACKGROUND: Reduced bone mineral density in patients with inflammatory bowel disease is thought to be due to disturbances in calcium homeostasis or the effects of corticosteroid treatment. AIMS: To assess the prevalence and mechanism of reduced bone mineral density in 79 patients with inflammatory bowel disease (44 with Crohn's disease, 35 with ulcerative colitis) who did not have significant risk factors for low bone densities. METHODS: Dual x ray absorptiometry was used to measure bone mineral density and serum and urinary markers of osteoblast (alkaline phosphatase, procollagen 1 carboxy terminal peptide and osteocalcin) and osteoclast (pyridinoline, deoxypyridinoline, and type 1 collagen carboxy terminal peptide) activities to assess bone turnover. RESULTS: There was a high prevalence of low bone mineral density (prevalence of T scores < -1.0 from 51%-77%; T scores < -2.5 (osteoporosis) from 17%-28%) with hips being more often affected than vertebrae (p < 0.001). Reduced bone mineral density did not relate to concurrent or past corticosteroid intake, or type, site, or severity of disease. Whereas calcium homeostasis was normal, bone markers showed increased bone resorption without a compensatory increase in bone formation. CONCLUSIONS: The greater prevalence of reduced hip bone mineral density, as opposed to vertebral, mineral density and the pattern of a selective increase in bone resorption contrasts with that found in other known causes of metabolic bone disease. 相似文献
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103.
Vivian I Binnie Siobhan McHugh William Jenkins William Borland Lorna M Macpherson 《BMC oral health》2007,7(1):5
Background
Tobacco use continues to be a global public health problem. Helping patients to quit is part of the preventive role of all health professionals. There is now increasing interest in the role that the dental team can play in helping their patients to quit smoking. The aim of this study was to determine the feasibility of undertaking a randomised controlled smoking cessation intervention, utilising dental hygienists to deliver tobacco cessation advice to a cohort of periodontal patients. 相似文献104.
A major factor in the ability of the placenta to avoid allograft rejection is the differential expression of MHC class I antigens on its surface. Using monoclonal antibodies and the electron microscopic immunogold technique, we have demonstrated that only the pregnancy-associated (Pa) antigen, which carries a broadly shared antigenic determinant, is expressed on the placental surface in the rat, whereas the allele-specific classical transplantation antigens are not. Both types of antigens are, however, present in the cytoplasm of the basal trophoblast but completely absent from the labyrinthine trophoblast. 相似文献
105.
Ann Macpherson 《Early child development and care》1993,86(1):61-77
This paper looks at issues which affect partnership between parents and professionals in Education. Such issues relate both to the variety of terminology used, which relates to the clarity with which “partnership” is conceived, and to the different professional groups who may see themselves as stakeholders in “partnership.” 相似文献
106.
J. Melrose A. Hall C. Macpherson C. R. Bellenger P. Ghosh 《Archives of orthopaedic and trauma surgery》1995,114(3):145-152
Chemonucleolysis is a therapeutic procedure whereby a degradative enzyme is injected intradiscally to reduce disc height/width by depolymerisation of extracellular matrix components. This process is considered to diminish disc pressure on inflamed nerve roots, resulting in the alleviation of sciatic pain. In the present study two krill (Euphasia superba) enzyme preparations, a proteinase and an esterase preparation, were evaluated for their potential as chemonucleolytic agents. Initially, their ability to degrade several protein (azocoll, casein, proteoglycans, PGs) and peptide (CBZ-arg-4-nitroanilide, CBZ-lys-thiobenzyl ester) substrates was assessed in vitro. The krill proteinase preparation rapidly converted azocoll, casein and PGs to small peptides. Furthermore, when this degradative enzyme preparation was evaluated in vivo, a relatively low intradiscal dose (0.54 mg/disc) was found to reduce intervertebral disc widths in beagles to 48% ± 10.5% (mean ± SEM) of their pre-injection values within 2 weeks of administration. Moreover, the discs injected with this proteinase had reconstituted up to 80% ± 9% (mean ± SEM) of their pre-injection widths at the termination of the experiment (32 weeks). These data suggest that the krill protease preparation has potential as a chemonucleolytic agent which would allow disc matrix reconstitution. Conversely, the krill esterase preparation also degraded PGs, but into relatively large fragments. This limited digestion of PGs indicates that the krill esterase would be a less effective chemonucleolytic agent than the corresponding proteinase. 相似文献
107.
Urvashi Surti Lori Hoffner Marta Kolthoff Jeanette Dunn Jennifer Hunt Lynn Sniezek Trevor Macpherson 《International journal of gynecological pathology》2006,25(4):366-372
We present a case of a dichorionic/diamniotic twin pregnancy in which one twin presented with ultrasound findings suggestive of molar changes in the placenta. The placenta of twin A seemed to be grossly enlarged and cystic, and twin A was small for gestation. After an inevitable abortion, a detailed histological and genetic evaluation was performed on the fetus and placenta from twin A, including traditional cytogenetic techniques, microsatellite marker analysis, fluorescent in situ hybridization, and p57 immunostaining. It was determined that twin A was a chimera with a biparental XX cell line and an androgenetic XY cell line. The 2 cell lines were present in both the placenta and the fetus. The patient later developed and was treated for persistent gestational trophoblastic disease, which has been shown to have an increased risk after an androgenetic conception. Cases of mosaicism or chimerism involving an androgenetic cell line may be difficult to diagnose histologically but are critical to identify because of the increased risk for persistent gestational trophoblastic disease. Therefore, we emphasize the importance of using multiple molecular, cytogenetic, and immunohistochemical techniques when diagnosing cases involving such unusual placental abnormalities. To our knowledge, this is the first reported case of persistent gestational disease after a fetal chimera. 相似文献
108.
109.
Changes in a postural strategy with inter-paw distance 总被引:1,自引:0,他引:1
110.