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Karen E. Hauer Calvin L. Chou Kevin H. Souza Duncan Henry Helen Loeser Christian Burke 《Teaching and learning in medicine》2013,25(4):284-290
Background: Optimal methods of preparing students for high-stakes standardized patient (SP) examinations are unknown. Purposes: The purpose is to compare the impact of two formats of a formative SP examination (Web-based vs. in-person) on scores on a subsequent high-stakes SP examination and to compare students' satisfaction with each formative examination format. Methods: Clustered randomized trial comparing a Web-based module versus in-person formative SP examination. We compared scores on a subsequent high-stakes SP examination and satisfaction. Results: Scores on the subsequent high-stakes SP examination did not differ between the two formative formats but were higher after the formative assessment than without (p < .001). Satisfaction was higher with the in-person than Web-based formative assessment format (4.00 vs. 3.62 on a 5-point scale, p = .01). Conclusions: Two formats of a formative SP examination led to equivalent improvement in scores on a subsequent high-stakes examination. Students preferred an in-person formative examination to online but were satisfied with both. 相似文献
74.
Wang F Wera G Knoblich GO Chou LB 《Foot & ankle international / American Orthopaedic Foot and Ankle Society [and] Swiss Foot and Ankle Society》2002,23(5):406-410
The risks of thromboembolism following operative treatment of ankle fractures are deep vein thrombosis (DVT) and pulmonary embolism (PE). These are potentially life-threatening complications. Many orthopedic surgeons fail to appreciate the potential complications of thromboembolic events because of their rare and delayed occurrence in foot and ankle operations. The purpose of this report is to describe the potential for DVT and PE following ankle operations. We present three cases in which patients who underwent operative treatment of ankle fractures subsequently developed PE. We also review the literature on the prevalence of thrombosis, risk factors, methods of prophylaxis, and use of prophylaxis in surgical procedures of the lower extremity. 相似文献
75.
BACKGROUND/AIM: Uremic patients are at an increased risk of being affected by tuberculosis (TB). Periodical tuberculin skin tests were suggested to detect TB-infected patients. These were replaced by chest radiographs in endemic areas like Taiwan. However, almost 50% of the TB incidence in dialysis patients was extrapulmonary. In this study, we tried to investigate the value of tuberculin tests in dialysis patients in endemic areas. METHODS: The patients were recruited from our dialysis unit. Purified protein derivative (PPD) and control tests with antigens for Candida and toxoid were performed using the Mantoux method. PPD with >10-mm induration will be considered positive. Skin anergy meant that the indurations of all antigens were less than 5 mm. A follow-up was done 12 months after the tests. RESULTS: A total of 177 patients were evaluated. Anergy was found in 40 patients (22.6%). A positive predictor of anergy was age >45 years (p = 0.03), while a negative predictor was prealbumin >20 mg/dl (p = 0.04). Fifty-three patients (30%) had positive PPD tests. Seven of the positive PPD patients (13.2%) developed active TB during the following years. Among the 40 patients with skin anergy, 6 (15%) were found to have active TB. Of the 48 patients (21.1%) with indurations of the PPD tests between 5 and 10 mm, none was found to have active TB. CONCLUSION: Although anergy will influence the sensitivity of PPD tests, these tests in combination with anergy tests could help to establish the diagnosis of TB in uremic patients, even in TB-endemic areas. 相似文献
76.
A Boening J Scheewe K Heine J Hedderich D Regensburger H-H Kramer J Cremer 《European journal of cardio-thoracic surgery》2002,22(2):167-173
OBJECTIVE: Review of the results of surgical correction of atrioventricular septal defects (AVSD), identification of risk factors for mortality and failure of left AV valve repair and determination of the impact of cleft closure on postoperative AV valve function. METHODS: Between 1975 and 1995, 121 consecutive patients (55 males, 66 females) underwent surgery for biventricular correction of AVSD with a median age of 1.2 years and a median weight of 7.6 kg. Sixty-five patients had a complete AVSD, 17 patients an intermediate type, and 39 patients a partial AVSD. The left AV valve (MV) cleft was closed in 53 patients (43.8%). The mean follow-up time is 7.2+/-4.6 years. RESULTS: Actuarial survival of the whole group after 1 year was 80%, after 10 and 20 years 78 and 65%, respectively. There were 18 early deaths (7-day mortality, 10.7%; 30-day mortality, 14.9%) and eight late deaths. In a univariate analysis, risk factors for early or late death were diagnosis of complete AVSD (P=0.006), no cleft closure (P=0.024), postoperative complications (P<0.0001), age <1.2 years (P=0.017), weight <7.6 kg (P=0.002), PA/Ao pressure ratio >0.7 (P<0.0001), and ECC time >110 min (P=0.002). In the multivariate analysis, postoperative complications (P=0.003) and PA/Ao pressure ratio >0.7 (P=0.001) had parallel effects on the postoperative risk for mortality. Moderate or severe MV regurgitation was present in six patients (6.0%) in the first evaluation after discharge and in 20 patients (20.4%) in the most recent postoperative control. There were 25 reoperations in 17 patients, of which 15 had to be performed for MV regurgitation and two for MV stenosis. Freedom from reoperation was 91% at 1 year, 79% at 10 years, and 76% at 15 and 20 years. We could not identify a statistically significant risk factor for reoperation. CONCLUSIONS: In patients with AVSD of various morphologies closure of the left AV valve cleft significantly improves outcome without affecting the need for reoperation. Risk factors for early and late death (multivariate analysis) were a pulmonary/aortic pressure ratio >0.7 and the occurrence of any complication after surgery. The concept of an early surgical AVSD correction before an increase in pulmonary vascular resistance and AV valve deformations occur would represent a better surgical option than a late correction as done in our series. Early correction allows for reduction of early mortality, superior long-term survival rates and a high freedom from subsequent valve degeneration. 相似文献
77.
The authors have shown that exogenous nitric oxide (NO) protects innervated skeletal muscle against reperfusion injury. This study further evaluated the effects of exogenous NO donor on denervated skeletal muscle. Forty-eight denervated rat cremaster muscles underwent 3 hr of ischemia, followed by 90 min of reperfusion, and received systemic infusion of 100 nmol/min s-nitroso-n-acetylcysteine (SNAC) or an equal amount of phosphate-buffered saline (PBS). Results showed that the average diameter in 10 to 20 microm arterioles was between 107 percent and 123 percent of baseline in the SNAC group, and between 55 percent and 84 percent in the PBS group during 90 min of reperfusion. These values in 21 to 40 microm and 41 to 70 microm arteries were between 100 percent and 110 percent in the SNAC group, and between 70 percent and 90 percent in the PBS group from 20 to 90 min of reperfusion. Compared to the PBS group, the SNAC group had a statistically significantly greater vessel diameter in both 10 to 20 microm (p<0.001) and 21 to 40 microm arterioles (p<0.01) during 90 min of reperfusion, and in 41 to 70 microm arteries (p<0.02) from 20 to 90 min of reperfusion. The overall blood flow of the muscle in the SNAC group increased from 37 percent of baseline at 10 min to 108 percent at 40 min of reperfusion, and remained above baseline thereafter. In contrast, this value in the PBS group was only between 27 percent and 68 percent of baseline during 90 min of reperfusion. The blood flow was statistically significantly (p<0.03) greater in the SNAC group than in the PBS group from 40 to 90 min of reperfusion. Among the conclusions were: (1) NO donor SNAC improves the microcirculation of denervated skeletal muscle during early reperfusion; and (2) this protection against reperfusion injury is independent of innervation in skeletal muscle. 相似文献
78.
儿童颈椎间盘钙化的诊断和治疗 总被引:2,自引:0,他引:2
目的 探讨儿童颈椎间盘钙化诊断和治疗的有效方法。方法 回顾性分析13例儿童的颈椎间盘钙化,其中上感后颈痛5例,外伤后偶然发现2例,突发颈部疼痛3例,突发斜颈3例。所有患者均经颈椎正、侧位X片证实。伴有疼痛症状应用非甾体抗炎镇痛药类药物,对于颈部症状较重则予预围外固定或短暂牵引后颈围外固定3-4周。结果 13例患儿共发现14个椎间隙的颈椎间盘钙化。经对症处理后临床症状均消失,所有的钙化均于5个月内完全消失。结论 儿童颈椎间盘钙化是一良性自限性疾病,正确认识其病理生理过程,可避免不必要的手术创伤。 相似文献
79.
BACKGROUND: Endoscopic thoracic sympathectomy or sympathicotomy of the lower part of the stellate ganglion is an efficient method for the treatment of craniofacial hyperhidrosis, but postoperative compensatory sweating may be troublesome in some patients. Needlescopic thoracic sympathetic block by clipping may achieve a similar effect as well as providing a possible reverse operation for patients who suffer from intolerable postoperative compensatory sweating. METHODS: Between January 1998 and June 2000, we collected a total of 28 patients with craniofacial hyperhidrosis. There were 15 men and 13 women with a mean age of 39.2 years (ranges, 19-50). All patients were placed under single-lumen intubated anesthesia in a semisitting position. Two ports were needed. We used a 2-mm 0 degrees thoracoscope and endo clips to perform a sympathetic block by clipping the lower third of the stellate ganglion at the second intercostal space. RESULTS: The operation was usually accomplished within 20 min (ranges, 15-30). All patients were discharged within 4 h after the operation. There were no surgical complications or surgical mortality cases. All patients achieved improvement of craniofacial hyperhidrosis without recurrent symptoms after a mean of 25.3 months (range, 12-41) of follow-up. Twenty-five patients (85.7%) developed compensatory sweating of the trunk and lower limbs. One of these patients could not tolerate this postoperative sweating; he therefore underwent a reverse operation and obtained improvement of the compensatory sweating 18 days after removal of the endo clips. CONCLUSION: Needlescopic thoracic sympathetic block by clipping is a safe and effective method for the treatment of craniofacial hyperhidrosis; compensatory sweating may be improved after a reverse operation and removal of the endo clips. 相似文献
80.
S.-S. Wang N.-K. Chou S.-C. Huang C.-H. Wang Y.-S. Chen W.-J. Ko 《Transplantation proceedings》2010,42(3):938-939