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Many medical schools still use oral examinations for the evaluation of clinical competence of students in their clerkship, although it has been proven that orals have poor reliability. This study investigates the feasibility and reliability of multiple oral examinations. Students in the last week of their Internal Medicine clerkship in an outpatient clinic were given several patient-based oral examinations. The student's performance was rated on a list of items reflecting clinical competence. A global judgement of the student's performance was also given. The results indicate that it is possible to increase the number of orals and the number of examiners in the day-to-day practice of an outpatient clinic moderately. The reliability when using a number of orals is better than the reliability of the common single oral examination. The reliability using global judgements appeared to be better than the reliability of averaged item scores.  相似文献   
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Background Preliminary data have shown encouraging results of a single intratumoral radiopharmaceutical injection that enables both sentinel node biopsy and probe-guided excision of the primary tumor in patients with nonpalpable breast cancer. The aim of the study was to evaluate this approach in a large group of patients. Methods Lymphoscintigraphy was performed in 368 patients with nonpalpable breast cancer after intratumoral injection of 99mTc-nanocolloid (.2 mL, 123 MBq, 3.3 mCi) guided by ultrasound or stereotaxis. The sentinel node was pursued with the aid of vital blue dye (1.0 mL, intratumoral) and a gamma ray detection probe. In case of breast-conserving surgery, the probe was used to guide the excision. Results At least one sentinel node could be identified intraoperatively in 357 patients (97%), of whom 69 had involved nodes (19%). Age over 60 years was associated with less frequent nonaxillary lymphatic drainage and absence of internal mammary chain dissemination. Tumor-free margins were obtained in 262 (89%) of the 293 patients who underwent segmental excision. Re-excision of the primary tumor bed was performed in six patients (2%). During a median follow-up of 22 months, one breast recurrence and one axillary recurrence were observed. Conclusions Lymphatic mapping and probe-guided tumor excision of nonpalpable breast cancer by intralesional administration of a single dose of 99mTc-nanocolloid and blue dye resulted in 97% identification of the sentinel node and in tumor-free margins in 89% of the patients who underwent breast-conserving surgery. Longer follow-up is needed to substantiate the accuracy and safety of this technique.  相似文献   
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OBJECTIVE: The aim of this study was to evaluate the incidence of postoperative deep vein thrombosis (DVT) in Chinese patients who underwent laparoscopic resection of rectal or sigmoid cancer in the absence of thromboprophylaxis. METHODS: Patients with adenocarcinoma of the sigmoid colon or rectum scheduled for laparoscopic resection were recruited. Neither chemoprophylaxis nor mechanical methods against DVT were employed. They were scheduled to have routine duplex ultrasound of both lower limbs perioperatively. RESULTS: In a 12-month period, 50 patients were recruited. Postoperative DVT occurred in 19 (38%) patients. None needed anticoagulation. Complete resolution of the thrombus was noted in 10 (53%) patients 12 weeks after operation, and in six patients 36 weeks after operation. Female sex was identified as being associated with a higher incidence of DVT. Age, smoking, preoperative neoadjuvant chemoirradiation, preoperative metastasis, duration of operation, conversion and postoperative complications did not appear to be risk factors for DVT. CONCLUSION: The incidence of asymptomatic calf vein DVT is relatively high after laparoscopic resection for rectosigmoid cancers in the Chinese population. However, complete resolution occurred without the use of anticoagulant therapy in the majority of cases. It is thus difficult to advocate the routine use of anticoagulant prophylaxis.  相似文献   
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宋淑军  Pagel  CN  Pike  RN  Mackie  EJ 《中国骨质疏松杂志》2008,14(1):20-22
目的 通过凝血酶对成骨细胞的增殖及分化作用的研究来探讨受体介导的凝血酶的功能.方法 原代成骨细胞分别取自于蛋白酶激活受体(protease-activated receptor,PAR)-1敲除鼠和野生对照鼠的头颅骨.并利用凝血酶,人工合成的PAR-1或PAR-4特异性激活短肽对细胞进行处理,通过对5.溴-2-脱氧尿嘧啶的嵌入及细胞碱性磷酸酶活性的测定探讨PAR-1或PAR-4激活对细胞增殖和分化的影响.结果 在野生鼠成骨细胞,凝血酶及PAR-1激活肽均能促进的细胞增殖和降低碱性磷酸酶的活性,但PAR-4激活肽却无这些作用.然而在PAR-1 敲除鼠的成骨细胞无论是凝血酶还是PAR-4激活肽均不能改变细胞的增殖及碱性磷酸酶的活性.结论 本研究结果 表明凝血酶促进成骨细胞增殖及抑制其分化是通过PAR-1介导的.其他凝血酶受体并不具有此作用.  相似文献   
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Acute appendicitis: CT and US correlation in 100 patients   总被引:18,自引:1,他引:18  
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