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41.
OBJECTIVE: Issues concerning the training and certification of surgical specialists have taken on great significance in the last decade. A realistic computer-assisted, tissue-based simulator developed for use in the training of cardiac surgical residents in the conduct of a variety of cardiac surgical procedures in a low-volume cardiothoracic surgery unit of a typical developing country is described. The simulator can also be used to demonstrate the function of technology specific to cardiac surgical procedures in a way that previously has only been possible via the conduct of a procedure on a live animal or human being. METHODS: A porcine heart in a novel simulated operating theatre environment with real-time simulated haemodynamic monitoring and coronary blood flow, in arrested and beating-heart modes, is used as a training tool for surgical residents. RESULTS: Standard and beating-heart coronary arterial bypass, aortic valve replacement, aortic homograft replacement and pulmonary autograft procedures can be simulated with high degrees of realism and with the superimposition of adverse clinical scenarios requiring valid decision making and clinical judgments to be made by the trainees. CONCLUSIONS: The cardiac surgical simulation preparation described here would appear to be able to contribute positively to the training of residents in low-volume centres, as well as having the potential for application in other settings as a training tool or clinical skills assessment or accreditation device. Collaboration with larger centres is recommended in order to accurately assess the utility of this preparation as an adjunctive cardiothoracic surgical training aid.  相似文献   
42.
43.
Postoperative radiation therapy in the management of lung cancer   总被引:1,自引:0,他引:1  
Postoperative radiation therapy for lung cancer is still controversial. In a 9-year period, 69 patients with non-oat-cell carcinoma of the lung (16% stage I, 26% stage II, and 58% stage III) received such therapy. The radiation dose was less than 5,000 cGy in 42 patients, 5,000-5,900 cGy in 16, and 6,000 cGy or more in 11; follow-up ranged from 24 to 64 months. Actuarial survival at 2 and 4 years was 50% and 16%, respectively, for squamous cell carcinoma, and 40% and 26% for adenocarcinoma. The 5-year survival for stages I, II, and III cancer was 29%, 17%, and 19%, respectively. Histologic findings and type of surgery did not affect survival, but the radiation dose apparently did. The 3-year survival for patients who received less than 6,000 cGy was 35%, compared with 73% for patients who received higher doses. In eight patients, treatment failed within the irradiated volume: all had received doses of less than 6,000 cGy, and the volume in three was judged to be inadequate.  相似文献   
44.
The ureteral access set was used 43 times during an 18-month period between 1984 and 1985. Stones lodged throughout the ureter and in the renal pelvis were extracted with a success rate of 51 per cent. Of the upper tract strictures 92 per cent were dilated successfully. Filling defects were diagnosed in 88 per cent of the cases. Foreign bodies were retrieved, Double-J stents were placed and biopsies were successful in each case. Ureteral perforation in 28 per cent of the cases was caused by the dilator in 8 of 12 (19 per cent over-all). The technique and short-term results are discussed. Long-term followup data are not yet available.  相似文献   
45.
Resection of a Wilms' tumor that extends into the vena cava or right atrium results in excellent survival when combined with adjuvant therapy. Preoperative identification of the presence of intravascular tumor thrombus and the level of vascular involvement is essential. It facilitates safe surgical resection, with cardiopulmonary bypass immediately available for retrohepatic and atrial tumors. Six patients with intracaval or intracardiac tumor thrombus were treated over a 5-year period with no perioperative deaths. Preoperative chemotherapy was useful in two patients with extensive tumors and pulmonary metastases. Our results using an integrated management plan suggest that an aggressive surgical approach is justified for this extensive variant of Wilms' tumor.  相似文献   
46.
Recognition of thalidomide defects.   总被引:4,自引:0,他引:4       下载免费PDF全文
  相似文献   
47.
A 12-year-old girl is described who developed rectal bleeding 5 months after being diagnosed as having a Coombs-positive hemolytic anemia. Colonoscopy showed that the rectal bleeding was due to ulcerative proctitis. This is the first case report of Coombs-positive hemolytic anemia preceding the onset of ulcerative proctitis in a child.  相似文献   
48.
49.
Weight at baseline and posttreatment was measured for 1096 participants in a smoking relapse prevention trial: 42.1% maintained their weight, 42.5% gained more than 1 kg and 15.4% lost more than 1 kg during the eight-week treatment program. Abstainers (n = 383) gained more than four times the weight gained by relapsers (n = 713) (Abstainers: 1.6 kg, Relapsers: 0.4 kg, p less than .0001). In order to examine the anorexic properties of nicotine gum. Abstainers were classified into nicotine gum user and non-user categories. Users gained significantly less weight than non-users although the difference was small (Users: 1.1 kg, Non-users: 1.8 kg, p less than .004). A dose-response relationship was observed between number of cigarettes smoked per day at baseline and weight gain. Higher cigarette consumption was associated with increased weight gain in both gum user (p less than .004), and non-user groups (p less than .02). There was no significant difference in weight gain between Abstainers who later relapsed at 6 months and those who maintained abstinence (p less than .29). Although the impact of nicotine gum on weight gain was small, this apparent property of the substance may be useful in encouraging cessation among smokers who perceive weight gain as a potential stumbling block to success.  相似文献   
50.
Nocturnal nasogastric feeding (NGF) supplementation is an effective means of supplying calories to children with chronic diseases which may impair caloric and nutritional intake. Herein, we describe our experience with 18 patients who were taught NGF. They were divided into two groups: one group was instructed in the hospital which is the typical situation, whereas the second group was instructed at home. No complications were associated with NGF taught either at home or in the hospital. Our experience, therefore, indicates that nocturnal NGF can be successfully taught at home.  相似文献   
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