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971.
972.
973.
Toward feasible, valid, and reliable video-based assessments of technical surgical skills in the operating room 总被引:1,自引:0,他引:1
OBJECTIVE: To determine the feasibility, validity, inter-rater, and intertest reliability of 4 previously published video-based rating scales, for technical skills assessment on a benchmark laparoscopic procedure. SUMMARY BACKGROUND DATA: Assessment of technical skills is crucial to the demonstration and maintenance of competent healthcare practitioners. Traditional assessment methods are prone to subjectivity through a lack of proven validity and reliability. METHODS: Nineteen surgeons (6 novice and 13 experienced) performed a median of 2 laparoscopic cholecystectomies each (range 1-5) on 53 patients within 2 Academic Surgical Departments. All patients had a diagnosis of biliary colic. Surgical technical skills were rated posthoc in a blinded manner by 2 experienced observers on 4 video-based rating scales. The different scales used had been developed to assess generic or procedure-specific technical skills in a global manner, or on a procedure-specific checklist. RESULTS: Six of 53 procedures were excluded on the basis of intraoperative difficulty. Of the remaining 47 procedures, 14 were performed by 6 novice surgeons and 33 by the 13 experienced surgeons. There were statistically significant differences between performance of the 2 groups on the generic global rating scale (median 24 vs. 27, P = 0.031), though not on procedural or checklist-based scales. All scales demonstrated inter-rater reliability (alpha = 0.58-0.76), though only the global rating scales exhibited intertest reliability (alpha = 0.72). CONCLUSIONS: Video-based technical skills evaluation in the operating room is feasible, valid and reliable. Global rating scales hold promise for summative assessment, though further work is necessary to elucidate the value of procedural rating scales. 相似文献
974.
Effect of left ventricular scar size, location, and transmurality on left ventricular remodeling with healed myocardial infarction 总被引:5,自引:0,他引:5
Orn S Manhenke C Anand IS Squire I Nagel E Edvardsen T Dickstein K 《The American journal of cardiology》2007,99(8):1109-1114
Studies of patients with acute myocardial infarction (MI) suggest that anterior transmural infarcts are associated with greater left ventricular (LV) remodeling compared with nontransmural nonanterior infarctions. It is unclear whether this relation also exists in long-term survivors of MI. Cardiac magnetic resonance imaging was used to explore the relation between myocardial scar size, localization, transmurality, and degree of long-term LV remodeling in patients with healed MI. Subjects were recruited from a registry of patients with healed MI who participated in the OPTIMAAL trial. Cardiac magnetic resonance imaging was performed to assess LV mass, volumes, LV ejection fraction, and myocardial scarring, adjusting for myocardial ischemia. Fifty-seven patients (mean age 69 +/- 10 years mean ejection fraction 49 +/- 13%) were studied 4.4 +/- 0.4 years after MI. Anterior scar was found in 19 patients and nonanterior scar in 33, whereas 5 patients did not show myocardial scar. Transmural scar was evident in 36 patients. In the 52 patients with scar, average total scar size was 13 +/- 8% of total LV mass. There was a strong linear relation between scar size and LV end-diastolic volume index (r = 0.81, p <0.0001), end-systolic volume index (r = 0.86, p <0.0001), and LV ejection fraction (r = -0.74, p <0.0001). In multivariate analysis, scar size was the strongest independent predictor of ejection fraction and LV volumes independently of scar localization and transmurality. In conclusion, in the studied cohort, there was a linear relation between scar size and ejection fraction and LV volumes. This relation was independent of scar location and transmurality. 相似文献
975.
Paraná R Paiva T Leite MR Oliveira FN Kali N Lobato C Dantas T Neto JT 《The American journal of tropical medicine and hygiene》2007,76(1):165-169
Clinical and epidemiologic studies on the hepatitis C virus (HCV) in the western Brazilian Amazon region are scarce. However, reports of clinical cases of hepatitis or pathologies associated to the HCV infection are frequent. In the state of Acre, there have been no studies on the population with the greatest exposure to parenteral transmission of virus infection. The objective of this study was to determine the prevalence of HCV infection among health care workers (HCWs) in this region. Of 2,338 HCWs, 646 were randomly selected for this study. The presence of antibody to HCV was determined. If these persons were antibody positive, they were tested for HCV RNA and the viral genotype was determined. The seroprevalence of antibody to HCV was 4.8% (31 of 646), and 3.7% (24 of 646) of those tested had detectable HCV RNA. Among these 24 viremic cases, HCV genotype 1 was most common (n = 16), followed by genotypes 3 (n = 6), 2 (n = 1), and an unidentified genotype. Infection with HCV (identified by a polymerase chain reaction) was more frequent among those with lower educational levels and lower incomes, those who lived for a longer period in the city of Rio Branco, those who reported intravenous use of vitamin complexes, those with a history of dental treatment, those with alcoholism, and women with history of caesarian parturition. The high prevalence of patients with HCV observed among HCWs in the city of Rio Branco and risk factors indicate the need for prevention and control programs, in addition to assistance programs, because this region is also hyperendemic for hepatitis B virus and hepatitis D virus. 相似文献
976.
Dorn T Kuhn U Bungartz G Stiller S Bauer M Ellwart J Peters T Scharffetter-Kochanek K Semmrich M Laschinger M Holzmann B Klinkert WE Straten PT Køllgaard T Sixt M Brakebusch C 《Blood》2007,109(6):2346-2355
RhoH is a small GTPase expressed only in the hematopoietic system. With the use of mice with targeted disruption of the RhoH gene, we demonstrated that RhoH is crucial for thymocyte maturation during DN3 to DN4 transition and during positive selection. Furthermore, the differentiation and expansion of DN3 and DN4 thymocytes in vitro were severely impaired. These defects corresponded to defective TCR signaling. Although RhoH is not required for TCR-induced activation of ZAP70 and ZAP70-mediated activation of p38, it is crucial for the tyrosine phosphorylation of LAT, PLCgamma1, and Vav1 and for the activation of Erk and calcium influx. These data suggest that RhoH is important for pre-TCR and TCR signaling because it allows the efficient interaction of ZAP70 with the LAT signalosome, thus regulating thymocyte development. 相似文献
977.
Falhammar H Filipsson H Holmdahl G Janson PO Nordenskjöld A Hagenfeldt K Thorén M 《The Journal of clinical endocrinology and metabolism》2007,92(1):110-116
CONTEXT: The chronic, often supraphysiological glucocorticoid doses used in congenital adrenal hyperplasia (CAH) might increase morbidity in cardiovascular disease and diabetes. OBJECTIVE: Our aim was to assess risk factors for cardiovascular disease and diabetes in CAH women. SUBJECTS, METHODS, AND DESIGN: We compared 61 women, 18-63 yr, with CAH due to 21-hydroxylase deficiency with 61 age- and sex- matched controls. Twenty-seven were younger than 30 yr, and 34 were 30 yr or older. Anthropometry, fat and lean mass measured by dual-energy x-ray absorptiometry, serum lipids, insulin, and adrenocortical steroids were studied. MAIN OUTCOME MEASURE: Body composition and cardiovascular risk factors were the main outcome measures. RESULTS: Younger patients and controls had similar waist to hip ratio, lean and fat mass, and insulin. Older patients had higher waist to hip ratio, lean mass, and insulin than controls. Fat mass was similar to controls but higher than in younger patients. Lipid profiles were slightly more favorable in older patients than controls. Gestational diabetes was more common in patients (21% of pregnancies vs. 0, P < 0.026). Few older patients had hypertension, cardiovascular disease, or diabetes. Despite moderate glucocorticoid doses, most patients had suppressed androgens. CONCLUSIONS: No clear evidence of unfavorable cardiovascular risk factors were found. Increased fat mass and higher insulin levels were, however, found in patients older than 30 yr. High frequency of gestational diabetes is a risk marker for future diabetes. Lifelong follow-up, lifestyle modifications, and attempts to adjust and reduce the glucocorticoid doses seem important. 相似文献
978.
Falhammar H Filipsson H Holmdahl G Janson PO Nordenskjöld A Hagenfeldt K Thorén M 《The Journal of clinical endocrinology and metabolism》2007,92(12):4643-4649
CONTEXT: Patients with classical congenital adrenal hyperplasia (CAH) receive lifelong, often supraphysiological, glucocorticoid therapy. Pharmacological doses of glucocorticoids are an established risk factor for osteoporosis. OBJECTIVE: Our objective was to evaluate bone mineral density (BMD), fracture prevalence, and markers of bone metabolism in adult females with CAH. DESIGN: This was a cross-sectional observational study. SETTING: Tertiary care referral centers were used in this study. PARTICIPANTS: We studied 61 women, aged 18-63 yr, with genetically verified CAH due to 21-hydroxylase deficiency. They were patients with salt wasting (n = 27), simple virilizing (n = 28), and nonclassical 21-hydroxylase deficiency (n = 6). A total of 61 age-matched women were controls. MAIN OUTCOME MEASURES: History of fractures was recorded. Total body, lumbar spine, and femoral neck BMD were measured by dual-energy x-ray absorptiometry. The World Health Organization criteria for osteopenia and osteoporosis were used. Serum marker of bone resorption, beta-C telopeptide was studied. RESULTS: The mean glucocorticoid dose in hydrocortisone equivalents was 16.9 +/- 0.9 mg/m2. Patients had lower BMD than controls at all measured sites (P < 0.001). In patients younger than 30 yr old, 48% were osteopenic vs. 12% in controls (P < 0.009). In patients 30 yr or older, 73% were osteopenic or osteoporotic vs. 21% in controls (P < 0.001). BMD was similar in the two classical forms and had no obvious relationship to genotypes. beta-C-telopeptide was decreased in older patients. More fractures were reported in patients than controls (P < 0.001). The number of vertebrae and wrist fractures almost reached significance (P = 0.058). CONCLUSIONS: Women with CAH have low BMD and increased fracture risk. BMD should be monitored, adequate prophylaxis and treatment instituted, and glucocorticoid doses optimized from puberty. 相似文献
979.
Medical observation, compared with parathyroidectomy, for asymptomatic primary hyperparathyroidism: a prospective, randomized trial 总被引:4,自引:0,他引:4
Bollerslev J Jansson S Mollerup CL Nordenström J Lundgren E Tørring O Varhaug JE Baranowski M Aanderud S Franco C Freyschuss B Isaksen GA Ueland T Rosen T 《The Journal of clinical endocrinology and metabolism》2007,92(5):1687-1692
CONTEXT: The clinical presentation of primary hyperparathyroidism (pHPT) has changed during the last half century, and the diagnosis is now more often made by chance in patients with no specific symptoms. OBJECTIVE: The present study is a randomized, controlled trial that investigates the effects of parathyroidectomy or medical observation in mild asymptomatic pHPT on morbidity and quality of life (QoL). DESIGN/SETTING/PATIENTS: A total of 191 patients (26 men) with asymptomatic pHPT [mean age 64.2 +/- 7.4 (sd) yr] were recruited in the study and randomized to medical observation (serum calcium level 2.69 +/- 0.08 mmol/liter) or surgery (2.70 +/- 0.08 mmol/liter). We here report baseline and 1 (n = 119) and 2 yr data (n = 99) on those who had completed the follow-up visits by the end of the inclusion period. RESULTS: At baseline, the patients had significantly lower QoL (SF-36) and more psychological symptoms, compared with age- and sex-matched healthy subjects. The two groups were similar at baseline, and no clinically significant changes in these parameters were seen during the observation time. Calcium and PTH normalized after surgery. The areal bone mineral density increased in the group randomized to operation, whereas the bone mineral density remained stable in the medical observation group. No change in kidney function (creatinine) or blood pressure was observed longitudinally or between the groups. CONCLUSIONS: Asymptomatic patients with mild pHPT have decreased QoL and more psychological symptoms than normal controls. No benefit of operative treatment, compared with medical observation, was found on these measures so far. 相似文献
980.