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Reforms to medical education have refocused curricula on the need to produce primary care physicians through a problem-based, student-centered, community-oriented, and integrated approach to instruction. Course evaluations, originally designed for traditional lecture-based, teacher-centered curricula, provide inadequate input from students to support curriculum planning and change and to determine appropriate mixes of educational methods. At the University of Toronto Faculty of Medicine, a unique community-centered course, called "Health, Illness and the Community," developed a student-centered course evaluation to provide adequate student input to support curriculum planning and change. A 35-item evaluation was developed to obtain data to identify student concerns, student learning styles, and preferred community agency utilization. The results suggest that student-centered course evaluation can play a role in managing and identifying key relationships in integrated and systematic courses as well as establishing a method for continual improvement.  相似文献   
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Our aim was to examine the feasibility of a totally laparoscopic insertion of a bifurcated aortofemoral bypass graft in a canine model and to compare the surgical results with those in control animals undergoing standard grafting and laparoscopic-assisted bypass procedures. Using a six-port approach, we exposed and cross clamped the aorta, tunneled a bifurcated Dacron graft, and performed an end-to-end aortic anastomosis while maintaining pneumoperitoneum by means of CO2. Proximal anastomoses were performed with 4/0 double-ended continuous Prolene sutures and distal anastomoses were performed through standard groin incisions. Total operating and aortic cross-clamp times were measured as was the total blood loss for each procedure. Clinical outcome was also documented. Eight female laboratory-bred hounds underwent successful totally laparoscopic aortobifemoral bypass grafting, eight underwent open grafting, and eight underwent laparoscopic-assisted bypass. Mean operating time was 193 minutes in the animals undergoing totally laparoscopic insertion vs. 156 minutes in the open group and 180 minutes in the laparoscopic-assisted group. Aortic cross-clamping time was also significantly longer at 87 minutes vs. 43 minutes (p < 0.001)=" in=" the=" totally=" laparoscopic=" group,=" but=" blood=" loss=" was=" less.=" all=" eight=" laparotomy=" and=" laparoscopic-assisted=" dogs=" were=" still=" alive=" with=" no=" complications=" at=" 28=" days,=" whereas=" three=" of=" the=" eight=" in=" the=" totally=" laparoscopic=" group=" showed=" evidence=" of=" temporary=" paraplegia.=" this=" experimental=" study=" demonstrates=" that=" a=" totally=" laparoscopic=" approach=" can=" be=" used=" to=" insert=" a=" bifurcated=" aortofemoral=" bypass=" with=" a=" proximal=" end-to-end=" anastomosis=" but=" currently=" does=" not=" save=" time=" and=" may=" increase=" the=" risk=" of=" neurologic=">Presented at the Twentieth Annual Meeting of the Peripheral Vascular Surgery Society, New Orleans, La., June 10, 1995.  相似文献   
64.
Data from a trial of preoperative whole body disinfection in postoperative wound infection prophylaxis involving 3733 patients were used to analyse the cost of a postoperative wound infection. The overall wound infection rate was 14.73% (513/3482), 61% of which were diagnosed after hospital discharge (312 outpatient infections versus 201 inpatient infections). This highlights the prevalence of the transfer of the cost of wound infection to the community. The inpatient and outpatient costs were calculated separately for those with and without a wound infection. Operative procedures were placed into 38 different categories. 12 of these 38 categories accounted for over 90% of the total number of operations performed. Overall, infected patients cost society more than noninfected patients. The hospitalisation costs for inpatients for all categories of patients, whether infected or not, comprised over 99% of the total cost. The excess cost for the infected patients in the study was calculated as 312 915 British pounds sterling (1990 British pounds sterling) or 610 British pounds sterling per infected patient, equivalent to 1926 hospital days overall. For some operations (e.g. stripping varicose veins) an excess of 52 hospital days were associated with wound infection diagnosed after discharge from hospital. Wound infections in some operative categories were consistently more expensive to manage (e.g. excess cost/infected vascular patient = 1085 British pounds sterling) while other operative categories had less costly wound infections (e.g. excess cost/infected thyroid patient = 110 British pounds sterling).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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BACKGROUND: There are few data on the morbidity and mortality of planned elective surgery for infrarenal abdominal aortic aneurysm (AAA) as a single surgeon series. This audit is of a consecutive series of AAA operations performed by one surgeon in one district general hospital over a 13-year period. METHODS: 243 patients were operated on for AAA between 1985 and 1998. Data were collected on the majority of patients prospectively. A reliable method was devised to identify all patients. Any missing complication and mortality data were then collected retrospectively. RESULTS: 13 patients died as a result of their operation (5.3%). In patients over the age of 80 years (36), five patients died (14%) and in the 207 patients under the age of 80 years, eight died (3.8%). Cardiac deaths were the most frequent cause (38%); 82 patients had recorded complications (34%). The operative mortality rate has increased in later years, (2.2% to 7.1%), largely due to an increase in the very elderly accepted for operation (12% to 16%), and a possible increase in co-morbidity. CONCLUSIONS: An acceptable and comparable mortality rate can be achieved in a district general hospital. The complication rate is high indicating the need for very intense medical and nursing care for these patients postoperatively. There is a considerable variance in mortality rates with age and risk even in the practice of one surgeon, indicating a need to be very knowledgeable and cautious in interpreting postoperative mortality data. This is the largest single surgeon series to date in the UK.  相似文献   
67.
BACKGROUND: Whole organ extracorporeal perfusion of a genetically modified humanized (transgenic) pig liver has been proposed as a technology that may sustain patients with severe liver failure while awaiting human liver transplantation. METHODS: We report on two cases of successful extracorporeal perfusion of a transgenic pig liver in patients awaiting transplantation for fulminant hepatic failure. The pig livers used were transgenic for human CD55 (decay-accelerating factor) and human CD59. These transgenic modifications are designed to reduce or eliminate the hyperacute rejection inherent in pig-to-primate xenotransplants. We also report on the results of serial surveillance testing for presence of the porcine endogenous retrovirus (PoERV) in these two patients. RESULTS: Extracorporeal perfusion in two patients was performed for 6.5 and 10 hr, respectively, followed by the successful transplantation of a human liver and resultant healthy patients (18 and 5 months later as of this writing). The porcine livers showed evidence of synthetic and secretory function (decreasing protime and bilirubin, bile production). Serial polymerase chain reaction analysis of these patients' peripheral blood mononuclear cells has failed to show presence of PoERV DNA sequences. CONCLUSIONS: The CD55/CD59 transgenic porcine liver appears capable of safely "bridging" a patient to liver transplantation. Human PoERV infection from these livers has yet to be demonstrated.  相似文献   
68.
Combination high dose rate brachytherapy (HDRB) and external beam radiation therapy is technically and clinically feasible as definitive treatment for localized prostate cancer. We report the first large Australian experience using this technique of radiation dose escalation in 82 patients with intermediate‐ and high‐risk disease. With a median follow up of 3 years (156 weeks), complications were low and overall prostate‐specific antigen progression‐free survival was 91% using the American Society for Therapeutic Radiology and Oncology consensus definition. The delivery of hypofractionated radiation through the HDRB component shortens overall treatment time and is both biologically and logistically advantageous. As a radiation boost strategy, HDRB is easy to learn and could be introduced into most facilities with brachytherapy capability.  相似文献   
69.
Predictive testing for BRCA1 and 2 mutations: a male contribution.   总被引:1,自引:0,他引:1  
BACKGROUND: Management strategies for women carrying BRCA1 and 2 mutations are becoming clearer and predictive testing for a known family mutation is commonly undertaken. Implications for men are not as clear and they participate less frequently. PATIENTS AND METHODS: Twenty-six men from 10 extended families underwent predictive testing. Their motivation, reaction and outcome were studied. Subjects had appropriate pre- and post-test counselling. Informed consent was obtained before predictive testing for known deleterious mutations. DNA analysis followed standard procedures. RESULTS: Eighteen tested positive and eight negative. Four had adverse psychological reactions and three reneged on their commitments to impart results. The spouse of another man had an adverse psychological reaction to the disclosure of his positive result. Two, already suffering from prostate cancer, were phenocopies and paternal lineage transmission was unexpectedly determined in another. Risk was removed from 33 offspring and confirmed for 56. CONCLUSIONS: Complex themes associated with genetic testing are confirmed and the spectrum extended. Men appear to understand the importance of participating in this process. Methods of avoiding adverse reactions merit further study along with other aspects of the process.  相似文献   
70.
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