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SUMMARY A case congenital dislocation of both knees and dislocation of the left hip in an infant whose mother had a chronic amniotic fluid leakage after mid-trimester amniocentesis. 相似文献
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Context Residents in all disciplines serve as clinical teachers for medical students. Since the 1970s, there has been increasing evidence to demonstrate that residents wish to teach and that they respond positively to formal teacher training. Effective resident‐as‐teacher (RaT) programmes have resulted in improved resident teaching skills. Current evidence, however, is not clear about the specific features of an effective RaT programme. Objectives This study was performed in order to investigate the effectiveness of RaT programmes on resident teaching abilities and to identify the features that ensure success. Methods of assessment used to ascertain the effectiveness of RaT programmes are also explored. Methods The literature search covered the period between 1971 and 2008. Articles focusing on improving resident teaching skills were included. Each study was reviewed by two reviewers and data were collected using a standard abstraction summary sheet. Study outcomes were graded according to a modified Kirkpatrick's model of educational outcomes. Results Twenty‐nine studies met review inclusion criteria. Interventions included workshops, seminars, lectures and teaching retreats. Twenty‐six studies used a pre‐ and post‐intervention outcome comparison method. Subjective outcome measures included resident self‐evaluation of teaching skills or evaluation by medical students, peers and faculty members. Objective outcome measures included written tests, evaluation of teaching performance by independent raters and utilisation of objective structured teaching examinations. One study objectively measured learning outcomes at the level of medical students, utilising the results of an objective structured clinical examination. Overall resident satisfaction with RaT programmes was high. Participants reported positive changes in attitudes towards teaching. Participant knowledge of educational principles improved. Study methodologies allowed for significant risks of bias. Conclusions More rigorous study designs and the use of objective outcome measures are needed to ascertain the true effectiveness of RaT programmes. Future research should focus on determining the impact of RaT programmes on learning achievement at the level of medical students. 相似文献
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高效液相色谱法测定右旋儿茶素血浆浓度及药代动力学参数 总被引:1,自引:0,他引:1
本文建立了体液中右旋儿茶素的RP-HPLC测定方法。采用C_(18)键合相硅胶为填料的固相提取柱进行样品预处理,右旋儿茶素的提取回收率为79.8%.应用二极管阵列检测器对色谱峰纯度进行鉴定。该法精密度好,方法回收率近100%,日内、日间的变异系数为2.4~5.6%,血浓69.6~1160 ng/ml范围内呈线性关系,r=0.9993。家兔静注右旋儿茶素18mg/kg,其药代动力学过程符合二室模型,分布相半衰期为0.129 h,消除相半衰期为1.19h。 相似文献
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Growth hormone effects on hypertrophic scar formation: a randomized controlled trial of 62 burned children 总被引:3,自引:0,他引:3
Gisele V. de Oliveira MD ; Arthur P. Sanford MD ; Kevin D. Murphy MD ; Hermes M. de Oliveira MD ; Judy P. Wilkins RGN ; Xiaowu Wu MD ; Hal K. Hawkins MD PhD ; Gregory Kitten PhD ; David L. Chinkes PhD ; Robert E. Barrow PhD ; David N. Herndon MD 《Wound repair and regeneration》2004,12(4):404-411
The hypercatabolism after massive pediatric burns has been effectively treated with recombinant human growth hormone, an anabolic agent that stimulates protein synthesis and abrogates growth arrest. While experimental studies have shown increased potential for fibrosis induced by growth hormone therapy, adverse effects on human scars have not been investigated. Our aim was to evaluate hypertrophic scar formation in 62 patients randomized to receive injections of 0.05 mg/kg/day of recombinant human growth hormone or placebo, from discharge until 1 year after burn. Scar scales were used to evaluate scar-severity at discharge, 6, 9, 12, and 18-24 months after burn, by three observers blinded to treatment. Computer-assisted planimetry allowed quantification of percentage of hypertrophic scar formation. Types I and III collagens were localized and quantified in scars and normal skin of patients from both groups, using immunohistochemistry with confocal laser microscopy analysis. Insulin-like growth factor-1 blood levels helped assess compliance. Statistical analysis showed that scar hypertrophy significantly increased from 6 to 12 months after injury in both groups, while decreasing at 18-24 months postburn. Types I and III collagens were statistically increased in the reticular layer of scars from both groups when compared to paired normal skin. Insulin-like growth factor-1 was significantly increased in the recombinant human growth factor-treated group. No differences were seen when recombinant human growth factor and control groups were compared using the scar scales, planimetry, or immunohistochemistry. We concluded that recombinant human growth hormone therapy did not adversely affect scar formation and should not contraindicate the administration of recombinant human growth hormone as a therapeutic approach to severely burned children. 相似文献
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石杉碱甲类似物的研究II.N-甲基吡啶酮石杉碱甲类似物的合成 总被引:4,自引:1,他引:3
石杉碱甲(1)是从中草药石杉属植物千层塔(Lycopodium serratum Thunb.)中分得的一种高效可逆的乙酰胆碱酯酶抑制剂,临床试验证实它对早老性痴呆症有显著疗效。本文报道N-甲基吡啶酮石杉碱甲类似物2和3的合成。2-甲氧基-5-甲氧羰基-11-亚甲基-5,9-甲撑环辛-7-烯并吡啶(9)在乙腈中用三甲基氯硅烷和碘化钠选择性脱保护以定量的产率得吡啶酮10,再用甲醇钠和碘甲烷甲基化得N-甲基吡啶酮11,11经碱性水解,Curtius重排和氨基的脱保护得N-甲基吡啶酮石杉碱甲类似物2。通过类似的途径从中间体2-甲氧基-5-甲氧羰基-7-甲基-11-酮-5,9-甲撑环辛-7-烯并吡啶(14)合成了类似物3。类似物2和3的乙酰胆碱酯酶抑制活性均低于天然石杉碱甲。 相似文献
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Recombinant human growth hormone accelerates wound healing in children with large cutaneous burns. 总被引:9,自引:1,他引:8
OBJECTIVE: Two forms of recombinant growth hormone that accelerate the healing of skin graft donor sites in severely burned children were evaluated. SUMMARY BACKGROUND DATA: Growth hormone has been shown to reduce wound healing times in burned pediatric patients. Through genetic engineering, several different forms have been synthesized; however, not all are marketed currently. Two forms of growth hormone were used in these studies, Protropin (Genentech, Inc., San Francisco, CA), a commercially available product that possesses a N-terminal methionine residue not found in the second form Nutropin (Genentech, Inc., San Francisco, CA), which, as yet, is not commercially available. Through the use of recombinant human growth hormone, rapid wound healing may reduce the hypermetabolic period, the risk of infection, and accelerate the healing of donor sites used for grafting onto burned areas. The two structurally different forms of growth hormone were tested for their efficacy in healing donor sites in severely burned children. METHODS: Forty-six children, with a > 40% total body surface area and > 20% total body surface area full-thickness burn were entered in a double-blind, randomized study to receive rhGH within 8 days of injury. Twenty received (0.2 mg/kg/day) Nutropin or placebo by subcutaneous or intramuscular injection beginning on the morning of the initial excision. Eighteen patients who failed the entry criteria for receiving Nutropin received Protropin therapeutically (0.2 mg/kg/day). Donor sites were harvested at 0.006 to 0.010 inches in depth and dressed with Scarlet Red impregnated fine mesh gauze (Sherwood Medical, St. Louis, MO). The initial donor site healing time, in days, was reached when the gauze could be removed without any trauma to the healed site. RESULTS: Donor sites in patients receiving Nutropin (n = 20) or Protropin (n = 18) healed at 6.8 +/- 1.5 and 6.0 +/- 1.5 (mean +/- SD) days, respectively, whereas those receiving placebo (n = 26) had a first donor site healing time of 8.5 +/- 2.3 days. Both groups receiving rhGH showed a significant reduction in donor site healing time compared with placebo at p < 0.01. When subgroups were compared, no difference in healing times could be shown with regards to age or time of admission after injury. CONCLUSION: Our results indicate that both forms of rhGH are effective in reducing donor site healing time compared with placebo and suggest that accelerating wound healing is of clinical benefit because the patients' own skin becomes rapidly available for harvest and autografting. With this increase in the rate of wound healing, the total length of hospital stay can be reduced by more than 25%. 相似文献
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P A Barrow 《Epidemiology and infection》1992,109(3):361-369