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Background: The lack of depth perception and spatial orientation in video vision are the drawbacks of laparoscopic surgery. The advent of a three-dimensional camera system enables surgeons to regain binocular vision and may be advantageous in complex laparoscopic procedures. Methods: We prospectively studied two groups of surgeons (with and without experiences in laparoscopic surgery) who performed a designated standardized laparoscopic task using a two-dimensional camera system (Olympus OTV-S4) vs a three-dimensional camera system (Baxter-V. Mueller VS7700) and compared their time performances. Results: The results suggested that only experience in laparoscopic surgery had significant effect on individual's performance. We could not demonstrate any superiority of the 3D system over the 2D system. However, two-thirds of the surgeons commented that the depth perception did improve. Conclusions: With further refinement of the technology, the 3D system may improve its potential in laparoscopic surgery.  相似文献   
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Lamivudine treatment in patients with chronic hepatitis B virus (HBV) infection may improve clinical state and suppress viral replication before liver transplantation. Emergence of lamivudine-resistant YMDD mutant is common. We report the results of liver transplantation in 16 patients with pretransplantation YMDD mutants after receiving lamivudine treatment for a median of 738 days (range, 400-1799 days). Adefovir dipivoxil (10 mg daily) was added on to lamivudine for a median of 20 days (range, 8-271 days) before (n = 11) or at (n = 5) liver transplantation, and the combination was continued indefinitely thereafter. Eight patients received additional intravenous hepatitis B immune globulin (HBIG) for a median of 24 months. Fifteen patients with known pre-adefovir HBV DNA levels had a median titer of 14,200 x 10(3) copies/mL (2 x 10(3) to 4,690,000 x 10(3) copies/mL), and 14 had HBV DNA >10(5) copies/mL. All but 1 patient remained positive for HBV DNA (by quantitative polymerase chain reaction [qPCR]) at the time of liver transplantation, and the titer was greater than10(5) copies/mL in 8 patients. The median follow-up after liver transplantation was 21.1 (range, 4.4-68.9) months. One patient (6%) died of an unrelated cause 12.2 months after transplantation, and 15 patients (94%) were alive with the original graft. All patients cleared HBV DNA and had no detectable HBV DNA by qPCR at the latest follow-up. Fourteen patients had cleared hepatitis B surface antigen (HBsAg), but 2 patients who received only adefovir dipivoxil and lamivudine without HBIG remained HBsAg positive after 7.7 and 9.5 months. Serum HBV DNA, however, was negative, and there was no biochemical or histological evidence of recurrence. Adefovir dipivoxil was well tolerated with no significant renal toxicity. In conclusion, a combination of add-on adefovir dipivoxil plus lamivudine therapy provides effective prophylaxis in patients with pretransplantation YMDD mutant that may be actively replicating. The cost effectiveness of additional passive immunoprophylaxis remains to be defined.  相似文献   
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OBJECTIVE: To justify the application of medialization thyroplasty in Chinese patients with symptomatic cancer-related unilateral vocal fold paralysis (UVFP). STUDY DESIGN AND SETTING: Retrospective chart review from February 2000 to March 2006. RESULTS: Eighty-seven Chinese patients undergoing medialization thyroplasty for UVFP were included; there were no significant differences between the cancer-related and benign groups in terms of the speech and swallowing rehabilitation outcome and the perioperative complication rate (P > 0.05). The median survival time of cancer-related UVFP patients from the date of medialization to death was 129 days. Age more than 65 years was identified as the only factor for a shorter survival period after medialization (P = 0.040). CONCLUSION: Medialization thyroplasty restores satisfactory speech and swallowing and has a low perioperative complication rate in Chinese patients with cancer-related UVFP. Postmedialization survival period was also reasonable. SIGNIFICANCE: Medialization thyroplasty is a justifiable treatment option for cancer-related UVFP.  相似文献   
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STUDY OBJECTIVES--To investigate the effects of passive exposure to tobacco smoke and gas cooking at home on respiratory symptoms and lung function of non-smoking women. SETTING--Evidence on the effects of passive smoking and exposure to nitrogen dioxide from gas cooking on the respiratory health of adults is limited and variable. Over 97% of women in Singapore do not smoke, and a principal source of indoor air pollution for housewives is passive smoking and gas cooking. DESIGN--This was a cross sectional (prevalence) study of a population based sample of 2868 adults aged 20 to 74 years in Singapore. A structured questionnaire administered by trained interviewers was used to collect data on passive smoking, gas cooking, respiratory symptoms, and other relevant variables. Passive smoking was defined as exposure to cigarette smoke from one or more members of the household who had ever smoked. Gas cooking was defined in terms of the weekly frequency of gas cooking, as well as the frequency with which the respondent's kitchen was filled with heavy cooking fumes (rarely, occasionally, often). Forced expiratory volume in one second (FEV1) was measured by using a portable Micro-spirometer. Multivariate analyses were used to estimate relative odds of association for respiratory symptoms and FEV1 effect, with adjustment for potential confounding variables. PARTICIPANTS--Of a total of 1438 women in the sample, 1282 women who had never smoked provided questionnaire data and 1008 women provided acceptable readings of FEV1 for analysis. MAIN RESULTS--Passive smoking was significantly associated with greater relative odds of usual or chronic cough and phlegm, wheezing, and breathlessness on exertion, as well as lower FEV1. Greater relative odds of respiratory symptoms were also associated with the weekly frequency of gas cooking, although these results were statistically insignificant. Chronic cough and phlegm and breathlessness on exertion, however, were significantly associated with the frequency with which the kitchen was filled with heavy cooking fumes. A lower FEV1 was found in women who cooked frequently (more than thrice a week). CONCLUSION--Domestic exposure to cigarette smoke and gas cooking is associated with increased risks of respiratory symptoms and impairment of lung function in non-smoking women in Singapore.  相似文献   
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进一步研究了抗三尖杉酯碱的HL-60细胞(HR20)抗细胞凋亡的机制及该抗性和抗药性的关系。结果表明,环孢菌素A(CsA)20,10μg·ml ̄(-1)诱导HL-60细胞发生凋亡,而阻断HR20细胞于G_1期,就不能诱导细胞发生凋亡。低浓度的CsA明显增加柔红霉素在HR20细胞内的积聚,其逆转抗药性作用与阻断细胞周期运行无关。CsA10μg·ml ̄(-1)处理HR20细胞,可引起50kDa的蛋白质高度磷酸化。结果提示:环孢菌素A阻断抗三尖杉酯碱的HL-60细胞于G_1期,而诱导敏感的HL-60细胞发生凋亡,其阻断作用与抗药性无关  相似文献   
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A neonate with severe respiratory distress due to a benign mediastinal teratoma (MT) is reported. Despite early and easy surgical excision of the tumor, the child died due to poor cardiac function. Only ten cases of MT in neonates have been reported in the literature so far. While the tumor has been known to interfere with lung development in utero, postnatal myocardial dysfunction due to poor heart development has not been previously documented. Accepted: 22 September 1997  相似文献   
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