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51.
Relationship of knee joint proprioception to pain and disability in individuals with knee osteoarthritis. 总被引:7,自引:0,他引:7
Kim L Bennell Rana S Hinman Ben R Metcalf Kay M Crossley Rachelle Buchbinder Michael Smith Geoffrey McColl 《Journal of orthopaedic research》2003,21(5):792-797
Proprioception plays an integral role in neuromotor control of the knee joint and deficits in knee joint proprioception are well documented in individuals with knee osteoarthritis (OA). However, the functional relevance of these deficits is not clear. This cross-sectional study evaluated the relationship between knee joint proprioception and pain and disability in a large cohort of individuals with knee OA. Two hundred and twenty participants (145 F, 75 M) with symptomatic knee OA were recruited from the community. Five non-weight bearing active tests with ipsilateral limb matching responses were performed at 20 degrees and 40 degrees flexion to measure knee joint position sense. Pain and disability were assessed by self-reported questionnaires and objective measures of balance and gait. Results showed little association between knee joint position sense variables and measures of pain and disability (r values <0.24, most p>0.05). When comparing participants with the worst and best joint position sense, no significant differences in pain and disability could be found (p>0.05). While our study design does not allow causality to be established, these results suggest that deficits in joint position sense may be due to factors other than pain and that deficits are not large enough to impact upon disability. 相似文献
52.
Jingxin Tianming Gang Geoffrey Ashley Lei Stephen T.C. 《Computerized medical imaging and graphics》2007,31(8):656-664
The human brain cortex is a highly convoluted sheet. Mapping of the cortical surface into a canonical coordinate space is an important tool for the study of the structure and function of the brain. Here, we present a technique based on least-square conformal mapping with spring energy for the mapping of the cortical surface. This method aims to reduce the metric and area distortion while maintaining the conformal map and computation efficiency. We demonstrate through numerical results that this method effectively controls metric and area distortion, and is computational efficient. This technique is particularly useful for fast visualization of the brain cortex. 相似文献
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Joseph Michaels th MD ; Michael Dobryansky MD ; Robert D.. Galiano MD ; Kirit A.. Bhatt MD ; Russell Ashinoff MD ; Daniel J. Ceradini MD ; Geoffrey C.. Gurtner MD 《Wound repair and regeneration》2005,13(5):506-512
The prevention of new blood vessel growth is an increasingly attractive strategy to limit tumor growth. However, it remains unclear whether anti-angiogenesis approaches will impair wound healing, a process thought to be angiogenesis dependent. Results of previous studies differ as to whether angiogenesis inhibitors delay wound healing. We evaluated whether endostatin at tumor-inhibiting doses delayed excisional wound closure. C57/BL6J mice were treated with endostatin or phosphate-buffered solution 3 days prior to the creation of two full-thickness wounds on the dorsum. Endostatin was administered daily until wound closure was complete. A third group received endostatin, but also had daily topical vascular endothelial growth factor applied locally to the wound. Wound area was measured daily and the wounds were analyzed for granulation tissue formation, epithelial gap, and wound vascularity. Endostatin-treated mice showed a significant delay in wound healing. Granulation tissue formation and wound vascularity were significantly decreased, but reepithelialization was not effected. Topical vascular endothelial growth factor application to wounds in endostatin-treated mice resulted in increased granulation tissue formation, increased wound vascularity, and wound closure approaching that of control mice. This study shows that the angiogenesis inhibitor endostatin delays wound healing and that topical vascular endothelial growth factor is effective in counteracting this effect. 相似文献
55.
Stacie E. Perlman M.D. Randolph B. Reinhold M.D. Geoffrey S. Nadzam M.D. 《Surgery for obesity and related diseases》2007,3(4):428-433
BACKGROUND: Little is known about the level of knowledge and comfort with bariatric surgery among family practice physicians. METHODS: Surveys were sent to all family practitioners in Connecticut querying the practice type and knowledge of bariatric surgery. The results were analyzed for the prevalence of opinion. RESULTS: Of 620 surveys sent out, 129 (21%) were completed. Of the 129 respondents, 73% were men, aged 31-79 years, and 92% were board certified, with an average of 19 years' experience. The average body mass index of respondents was 26 kg/m2 (range 16-40). Only 4% of respondents had a body mass index >30 kg/m2. Physicians reported a patient obesity rate of 43%. Of the 129 respondents, 88% believed obesity was difficult to control with diet and exercise alone. Only 6% thought obesity was best controlled surgically. Also, 85% of respondents had referred a patient for gastric bypass, although only 57% were comfortable explaining the procedure. The most common reason for refusal to refer was fear of complications and death. Additionally, 55% correctly listed a body mass index of 40 kg/m2 as qualifying for bariatric surgery without comorbidities; 48% identified the mortality rate of surgery as <1%, with 4% of respondents reporting >10%; and 84% were familiar with gastric bypass, 66% with LapBand, 33% with vertical banded gastroplasty, and 5% with duodenal switch. The respondents believed that nausea was the most common side effect, followed by anemia and fatigue. Finally, 53% believed bowel obstruction was common. CONCLUSIONS: The results of our study have shown that misconceptions about bariatric surgery exist in the family practice community despite the increasing frequency of these procedures. Educational programs need to be designed to assist family practitioners in treating and referring obese patients. 相似文献
56.
Mano J. Thubrikar Michel R. Labrosse Kenton J. Zehr Francis Robicsek Geoffrey G. Gong Brett L. Fowler 《European journal of cardio-thoracic surgery》2005,28(6):850-855
Objective: Valve-sparing surgery can be used in patients with dilated aortic roots and aortic insufficiency (AI) but has not become a common practice, in part because the spared valve may be incompetent. Our goal was to study how the dimensions of the aortic root and leaflets have changed in such patients. Methods: Fourteen patients with dilated aortic root and AI were examined by transesophageal echocardiography. The annulus diameter, sinotubular junction (STJ) diameter, sinus height, leaflet free-edge length, and leaflet height were measured. Correlations among these dimensions and with the AI grades were explored. Measurements were also made in 19 normal human aortic valves from silicone molds. Results: There was no evident change in the average diameter of the annulus between the normal valves and those in the dilated aortic roots. The STJ diameter was obviously increased in the dilated aortic roots; the aortic sinuses also appeared to be taller and the leaflets larger than normal. The leaflet free-edge length, the leaflet height, and the sinus height were found to increase with the dilated STJ diameter. The degree of AI was not found to correlate well with any of the dimensions measured. Conclusions: The dimensions of the leaflets may change parallel to aortic root dilatation with AI. Therefore, during valve sparing, it may be necessary to correct both the dilatation of the root and the leaflet free-edge length to achieve a competent valve. 相似文献
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A patient with Type I hypoplastic patterned amelogenesis imperfecta, subtype D, presented for prosthodontic evaluation. This article describes the developmental and pathophysiological background of this disease. A clinical report describing the diagnosis, treatment planning, and dental rehabilitation of the patient is reviewed. 相似文献
59.
Summary The MCF-7 cell S9 fraction and whole MCF-7 cells can mediate one-electron-redox cycling of doxorubicin, giving rise to concomitant oxidation of reduced nicotinamide adenine dinucleotide phosphate (NADPH), formation of a drug semiquinone free radical, consumption of molecular oxygen and formation of superoxide anions and hydroxyl radicals. Doxorubicin redox cycling was consistent with DNA strand breakage and cell kill in MCF-7 cells. In contrast, no evidence for redox cycling was found for mitoxantrone (MIT), CI941 or ametantrone (AMET) in MCF-7 cells. Despite the absence of redox cycling, the CI941, MIT, and AMET concentrations resulting in 50% mortality (LC50; 1.5×10–10, 5.2×10–9 and 1.2×10–6
m, respectively) of MCF-7 cells were lower than that of DOX (3.0×10–6
m). Furthermore, the higher cytotoxicity of MIT and CI941 as compared with AMET or DOX was associated with greater efficiency in inducing DNA strand breakage in MCF-7 cells as determined by alkaline elution. Sine MIT and CI941 proved to be the most potent DNA-damaging and cytotoxic agents in this study, the ability of DOX to undergo redox cycling does not appear to confer increased cytotoxic potential on this agent. The present study revealed several important aspects with regards to the structural modification of anthraquinone antitumour agents. Firstly, the C1 and C4 postitioning of the hydroxyethylamino side chains on MIT, CI941 and AMET is associated with a lack of flavin reductase-mediated activation of these agents. Secondly, the possession of a C5 or C8 aromatic hydroxyl group appears to be intimately involved in the enhanced DNA strand breakage and cytotoxic potency of MIT and CI941, since AMET does not possess these groups. These findings indicate that future development of quinone antitumour agents should concentrate on compounds that do not undergo redox cycling but do possess aromatic hydroxyl groups, since the latter appear to be responsible for the enhanced cytotoxicity of MIT and CI941.Abbreviations DOX
doxorubicin
- MIT
mitoxantrone
- AMET
ametantrone
- SOD
superoxide dismutase
- DMPO
5,5-dimethyl-1-pyrroline-N-oxide
- ESR
electron spin resonance
- SSF
strand scission factor
This work was funded by the Cancer Research Campaign (UK) 相似文献
60.