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31.
Comparison of video trainer and virtual reality training
systems on acquisition of laparoscopic skills 总被引:11,自引:5,他引:6
Hamilton EC Scott DJ Fleming JB Rege RV Laycock R Bergen PC Tesfay ST Jones DB 《Surgical endoscopy》2002,16(3):406-411
Training on a video trainer or computer-based minimally invasive surgery trainer leads to improved benchtop laparoscopic skill. Recently, improved operative performance from practice on a video trainer was reported. The purpose of this study was three fold: (a) to compare psychomotor skill improvement after training on a virtual reality (VR) system with that after training on a video-trainer, (VT) (b) to evaluate whether skills learned on the one training system are transferable to the other, and (c) to evaluate whether VR or VT training improves operative performance. For the study, 50 junior surgery residents completed baseline skill testing on both the VR and VT systems. These subjects then were randomized to either a VR or VT structured training group. After practice, the subjects were tested again on their VR and VT skills. To assess the effect of practice on operative performance, all second-year residents (n = 19) were evaluated on their operative performance during a laparoscopic cholecystectomy before and after skill training. Data are expressed as percentage of improvement in mean score/time. Analysis was performed by Student's paired t-test. The VR training group showed improvement of 54% on the VR posttest, as compared with 55% improvement by the VT group. The VR training group improved more on the VT posttest tasks (36%) than the VT training group improved on the VR posttest tasks (17%) (p <0.05). Operative performance improved only in the VR training group (p <0.05). Psychomotor skills improve after training on both VR and VT, and skills may be transferable. Furthermore, training on a minimally invasive surgery trainer, virtual reality system may improve operative performance during laparoscopic cholecystectomy. 相似文献
32.
Honorati Masanja Joanna Armstrong Schellenberg Hassan M Mshinda Meera Shekar Joseph KL Mugyabuso Godwin D Ndossi Don de Savigny 《BMC health services research》2006,6(1):142
Background
Efficient delivery strategies for health interventions are essential for high and sustainable coverage. We report impact of a change in programmatic delivery strategy from routine delivery through the Expanded Programme on Immunization (EPI+) approach to twice-yearly mass distribution campaigns on coverage of vitamin A supplementation in Tanzania 相似文献33.
NRM Buist AP Prince KL Huntington JM Tuerck DD Waggoner 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(S407):75-77
A new amino acid mixture for incorporation into medical foods for the treatment of hyperphenylalaninemia has been tested in a regular clinic. The mix is designed to be as unobtrusive as possible, consistent with good nutrition. After more than 1 year of trial as a beverage, we have shown that it is safe and well tolerated but that plasma phenylalanine is no better controlled than with some other products. The mix can be incorporated into a large number of different foods without affecting the taste. Occult monitoring of the quantity of medical foods purchased compared with the amounts reported to be consumed in diet histories provides an excellent way to monitor dietary compliance. 相似文献
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Insufficiency fractures in the supraacetabular region were identified in five women, aged 55-83 years. Factors contributing to the diminished resistance of their bones included postmenopausal osteoporosis, steroid therapy, radiation therapy, and rheumatoid arthritis. The supraacetabular fractures were seen on routine radiographs as hazy bands of sclerosis located immediately above and parallel to the acetabular roof. All five patients had additional fractures in the spine or pelvis. Supraacetabular insufficiency fractures may be an unsuspected cause of hip pain, especially in older women. 相似文献
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39.
Asmuth DM Busch MP Laycock ME Mohr BA Kalish LA van der Horst CM;Viral Activation Transfusion Study 《Antiviral research》2004,63(2):123-131
Chronic infection with either hepatitis B (HBV) or hepatitis C virus (HCV) is frequently present in patients seropositive for human immunodeficiency virus (HIV) because of shared routes of transmission. With the advent of highly active antiretroviral therapy (HAART) regimens capable of controlling HIV replication and dramatically prolonging the survival of HIV-infected patients, the impact of co-morbid infections such as HBV and HCV has come into focus. Several studies have monitored HBV or HCV viral loads following initiation of HAART, with disparate results. The effects of HAART on hepatitis B and C plasma viral loads (n = 9 and 32, respectively) and on liver enzyme levels were studied in a large cohort of prospectively studied subjects with advanced stage HIV disease. Comparing the mean pre- and post-HAART levels, there was an estimated increase of (a) 1.40 log(10) from 4.83 to 6.24 log(10) for HBV plasma viral load (P = 0.07), (b) 0.74 log(10) from 6.38 to 7.12 log(10) for HCV plasma viral load (P = 0.001), and (c) 19.4 U/L from 37.4 to 56.8 U/L for serum alanine aminotransferase (P < 0.001). While the number of subjects co-infected with HIV and HBV was limited, these data collected in a population of advanced stage HIV-infected patients raises questions regarding the interactions of these viruses with each other and the host immune system and has implications regarding the order in which antiviral therapies are initiated. 相似文献
40.
BACKGROUND: Studies examining the outcomes of surgery for gastroesophageal reflux disease (GERD) have consisted primarily of case series. We sought to assess trends in both utilization and outcomes of antireflux surgery from a national perspective. METHODS: Using ICD-9 codes, we identified all antireflux procedures (N = 24,208) performed on adults from 1990 to 1997 in hospitals participating in the Nationwide Inpatient Sample, the largest all-payer inpatient care database in the United States. Using sampling weights and U.S. Census data, we then calculated the national population-based rate of antireflux surgery for each year and examined secular trends in utilization, in-hospital mortality, splenectomy (a technical complication), and length of hospital stay. Using a coding algorithm, we also assessed trends in the proportion of procedures performed via the laparoscopic, open abdominal, and thoracic approaches. RESULTS: From 1990 to 1997, the population-based annual rate of antireflux surgery increased from 4.4 to 12.0 per 100,000 adults. A substantial increase in utilization was observed from 1993 to 1995, but annual rates before and after this period were relatively stable. Between 1990 and 1997, in-hospital surgical mortality decreased from 1.2% to 0.5% (p = 0.002), splenectomy rates decreased from 3.9% to 1.5% (p <0.001), and median length of stay decreased from 7 to 2 days (p <0.01). The proportion of antireflux procedures performed laparoscopically increased from 0.5% to 64% (p <0.001), and the proportion of procedures performed using a thoracic approach decreased from 12% to 1% (p <0.001). CONCLUSIONS: With the dissemination of the laparoscopic approach, the population-based rate of antireflux surgery has more than doubled. At the same time, operative mortality and splenectomy risks have diminished. 相似文献