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91.
92.
S. Y. Wong E. M. Lau W. W. Lau† & H. S. Lynn 《Journal of human nutrition and dietetics》2004,17(4):359-364
To determine the feasibility of increasing the calcium, protein and calorie intake of osteoporotic fracture patients by repeated dietary counselling delivered by a dietitian, a randomized controlled trial was conducted. Among 189 patients presenting with osteoporotic fractures to an Orthopaedics and Traumatology Department of a large regional hospital, 98 patients were randomized to the intervention group and 91 were randomized to the control group (with usual care). Intervention group received three sessions of dietary counselling with tailored made recommendations over a period of 4 months, while the control group only received dietary assessment and pamphlets on the prevention of osteoporosis. Almost all subjects in both intervention and control groups had calcium intake below the recommended level of 1000 mg at baseline. Half and 60% of subjects in both groups had total energy and protein intake below recommended levels respectively. The mean weights of control and intervention groups at baseline were 51.5 and 50.9 kg respectively, while the body mass index (BMI) were 22.6 (kg m(-2)) and 22.6 (kg m(-2)) respectively. After dietary intervention, significant increase of intake was seen in calcium intake (P = 0.0095 by t-test) in the intervention group. No significant increase was seen in protein or calorie intake. No significant change was observed in the body weight or BMI although there was a positive trend in the intervention group for all these parameters. We concluded that there was general malnutrition in Chinese elderly who presented with osteoporotic fractures. Dietary calcium could be increased by repeated professional dietary counselling. Future studies with longer duration and more objective clinical outcomes will be helpful to further demonstrate the long-term effects of dietary intervention on osteoporosis and other chronic diseases. 相似文献
93.
Anne K. Wong 《Journal canadien d'anesthésie》2004,51(5):455-464
PURPOSE: With the advent of competency-based curriculum, technology such as full scale computer simulators have acquired an increasingly important role in anesthesia both in training and evaluation. This article reviews the current role of full scale computer simulators in teaching and evaluation in anesthesia. SOURCE: This review draws from existing anesthesia and medical education literature in order to examine and assess the current role of full scale computer simulators in anesthesia education today. PRINCIPAL FINDINGS: The last decade has witnessed a major increase in the use of full scale computer simulators in anesthesia. Many applications have been found for these simulators including teaching and training, evaluation and research. Despite the increasing use and application of full scale computers in anesthesia in the area of teaching and training, definitive studies evaluating its cost effectiveness, its efficacy compared to traditional training methods or its impact on patient outcome are still pending. Although there is some preliminary evidence of reliability and validity in using the simulator to evaluate clinical competence, development in this area has not progressed enough to justify its use in formal, summative evaluation of competence in anesthesia at this time. CONCLUSIONS: As technology acquires an increasingly important role in medical education, full scale computer simulators represent an exciting potential in anesthesia. However, the full potential and role of simulators in anesthesia is still in development and will require a dovetailing of clinical theory and practice with current research in medical education. 相似文献
94.
Wong Merng Koon 《中华创伤骨科杂志》2006,8(10):944-948
Objective Intra-articular fractures of the distal radius in young adults comprise a distinet fracture pattern that is diffficuh to manage and associated with a high frequency of post-traumatic arthritis.Restoration of articular congruency and alignment should improve the outcome.Methods In this study we prospectively re- viewed the results of 21 consecutive cases of dorsally displaced intra-articular distal radius fractures which were treated with internal fixation after failing to achieve articular congruency with closed reduction.Results 3 patients were lost to follow-up.For the rest of 18 patients,follow-up time ranges from 18 to 75 weeks the fractures had healed with highly satisfactory radiographic and functional results.The final volar tilt averaged 4.9°;radial inclination 23.9°;radial length 14mm;and articular incongruity,0.1 mm.Wrist motion at final follow-up examination aver- aged flexion 62°,extension 60°,radial deviation 16°,ulnar deviation 27°,pronation 77°and supination 74°.Grip strength averaged 83% of the uninjured side.The overall outcome of 18 patients(94.4%)had a good or excellent result according to the system of Gartland and Werley and 18 patients(72.2%)had a good result according to the modified system of Green and O'Brien at the most recent evaluation.The only complication in this series was a superficial pin tract infection,which was rapidly resolved with removal of pins at 5th week of external fixation. Conclusion Thus restoration of articular congruency and alignment is possible with minimal complication using modern non-angular stable methods of internal fixation. 相似文献
95.
Blue rubber bleb nevus syndrome (BRBNS), which consists of cutaneous and visceral hemangiomas, is a rare disease. Complications such as gastrointestinal (GI) bleeding, anemia and coagulopathy have been documented. We report a patient with BRBNS who presented with acute paraparesis in addition to GI bleeding and coagulopathy. 相似文献
96.
97.
Long-term effects of physiologic concentrations of dexamethasone on human bone-derived cells 总被引:2,自引:0,他引:2
M M Wong L G Rao H Ly L Hamilton J Tong W Sturtridge R McBroom J E Aubin T M Murray 《Journal of bone and mineral research》1990,5(8):803-813
Bone cells derived from human trabecular explants display osteoblastic features. We examined the modulation of alkaline phosphatase activity and cAMP production as the result of exposing trabecular explants to physiologic concentrations of dexamethasone for 4 weeks during cellular outgrowth and subculture. Cells treated with dexamethasone were observed to grow generally more slowly than control cells. Cells appeared larger and more polygonal, and staining for alkaline phosphatase was more intense in the dexamethasone-exposed cultures. There was a progressive increase in cellular PTH responsiveness with increasing duration of exposure of cells to dexamethasone. Cells grown for 6 weeks in 3 x 10(-8) M dexamethasone had a 10-fold increase in PTH-stimulated cyclic AMP accumulation. Dexamethasone-treated cells also had a significantly increased alkaline phosphatase activity. 1,25-(OH)2D3-stimulated alkaline phosphatase activity was increased approximately 20-fold. cAMP responses were significantly increased to PTH (21.7-fold), PGE1 (2.67-fold), and forskolin (4.81-fold), but not to cholera toxin. Dexamethasone-treated cells also had a mean decrease in 1,25-(OH)2D3-stimulated osteocalcin production to 26.2% of control values (p less than 0.001). Hydrocortisone treatment gave rise to similar effects but of smaller magnitude than those of dexamethasone. Testosterone did not have a significant effect on alkaline phosphatase activity or cAMP production. Skin fibroblasts showed a significant enhancement of alkaline phosphatase activity in response to dexamethasone, but of a much smaller magnitude than in bone cells. The phenotypic changes induced by long-term culture in dexamethasone are consistent with the promotion of a more differentiated osteoblastic phenotype. 相似文献
98.
对三年生番荔枝(Ancnona squamosa L.)实生树的开花生物学和人工授粉进行了研究并发现;番荔枝的花有两荔异熟现象,人工授粉能提高座果率,简便而有效的方法是用毛笔直接从树上花药自然裂开的花上聚花粉并立即授在花药没裂开的花上,授粉后两周的座果率达87.9%,授 在花药裂开的花上,座果率为5.3%,与对照照座果率4.4%没有区别,说明花药裂开柱头容受性完全消失,花药裂开时间与品种特有关,目前,广东栽培的番荔枝分为花药早上裂开和傍开两种类型,这两种类型的不同品种之间授粉也能提高座果率,授粉后两周的座果率为83.3%。说明花裂开关12h柱头容受性仍完全正常。 相似文献
99.
100.
The efficacy and toxicity of the siderophore desferrithiocin (DFT), which has shown potential application in iron chelation therapy, were assessed in vivo and in vitro. DFT was evaluated in vivo in two ways: firstly, by measuring the effect of a single dose of DFT (10-100 mg/kg) on 59Fe excretion in iron-loaded rats labelled with 59Fe; and secondly, by examining the effect of the daily oral administration for 2 weeks of DFT (10-25 mg/kg/d) on the growing rat. DFT and its ferric complex, ferrithiocin (FT), were assessed in vitro from their effects on transferrin and iron uptake and mobilization from rat hepatocytes in culture using transferrin doubly labelled with 125I and 59Fe. Both oral and subcutaneous DFT were highly effective in promoting iron excretion in vivo, but showed evidence of toxicity after oral administration for 2 weeks at 25 mg/kg/d. In addition, DFT was much more effective than desferrioxamine or pyridoxal isonicotinyl hydrazone in reducing hepatocyte iron in vitro. However, FT was cytotoxic, causing membrane disruption and release of intracellular aspartate aminotransferase. It was concluded that DFT should not be considered for chronic iron chelation therapy without extensive further evaluation. 相似文献