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Using a quantitative immunoautoradiographic technique with simultaneously exposed internal standards, antigenic sites on A1, A1B, A2 and A2B erythrocytes were quantitated. The binding of purified radioiodinated rabbit anti-A antibodies was studied by the direct incubation technique. 61 normal individuals and 44 patients suffering from leukaemia and other haematological disorders such as polycythaemia vera (PV) and aplastic anaemia (Apl.A) were investigated. Among the normal volunteers, antigenic sites gradually increased up to 3 months of life, later on they were comparable with the values of adults. A reduction of more than 50% in the antigenic sites was observed in all cases of Apl.A. 50-70% of patients with various forms of leukaemia had a decrease in antigenicity. 1 patient suffering from acute unclassified leukaemia showed two populations of red cells. This case differed from natural O/A1 chimerism where A1 erythrocytes had normal antigenicity while in the patient, A1 antigens were depressed. 2 patients (1 with acute lymphoblastic leukaemia, 1 with Apl.A) who were investigated after allogenic bone marrow transplantation had a marked decrease in antigenic sites. Reasons for A antigenic variations in haematological disorders are discussed.  相似文献   
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Chronic alcohol administration leads to hepatic membrane alterations which, at least in part, are due to lipid peroxidation and may contribute to the toxicity of ethanol at the level of the hepatocyte. Because changes in testicular function also occur after chronic administration of ethanol to rats, we evaluated testicular mitochondria for evidence of alcohol-associated peroxidation injury which might contribute to the gonadal injury that occurs with prolonged use of the drug. Lipid peroxidation was assessed through measurement of diene conjugates, polyenoic fatty acid composition, malonaldehyde formation, and testicular reduced glutathione levels. Compared to isocalorically matched dextrimaltose-fed controls (ISO), rats fed alcohol (ETOH) for 50 days had a decreased content of polyenoic acids and a compensatory increase in saturated fatty acids [ETOH, 50.69 +/- 0.65% (by wt); ISO, 52.93 +/- 0.72 (mean +/- SE); P less than 0.01]. This decrease in polyunsaturated fatty acid content was accompanied by an increase in diene conjugates in testicular mitochondria (ETOH, 0.455 +/- 0.053 OD units at 233 nm/mg lipid; ISO, 0.382 +/- 0.045; P less than 0.05). An increase in malonaldehyde formation also was observed in the alcohol-fed rats compared to the control level (ETOH, 21.39 +/- 1.67 nmol/mg protein; ISO, 17.50 +/- 1.39; P less than 0.05) as well as a decrease in glutathione content (ETOH, 1218 +/- 89 micrograms GSH/testes; ISO, 1638 +/- 89; P less than 0.05). Taken together, these findings support the concept that lipid peroxidation may be an important mechanism responsible, at least in part, for the toxic effect of ethanol on the testes.  相似文献   
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BACKGROUND: After total knee arthroplasty, patients regularly suffer from severe pain. It is unclear whether epidural or systemic pain therapy is superior in terms of postoperative pain relief, patients' comfort and side effects. A new therapeutic approach, intraarticular opioids, has been suggested with the detection of opioid receptors in inflamed tissue. This method has proven suitable for clinical use in small operations (e.g. knee arthroscopy). In this study, we compared epidural analgesia and intraarticular application of morphine plus "on-demand" intravenous analgesia to "on-demand" intravenous analgesia alone. METHODS: Thirty-seven patients, scheduled for total knee arthroplasty, were randomly assigned to three treatment groups: in group 1 (EPI) patients received bolus doses of morphine via an epidural catheter; in group 2 (IA) an intraarticular bolus of 1 mg of morphine was applied at the end of the operation with subsequent use of a patient-controlled analgesia (PCA) pump; group 3 (Control), in which only PCA was provided, served as control for both analgesic procedures. Main outcome measures included visual analogue pain scales, total morphine consumption, and stress hormones. RESULTS: No statistically significant differences in visual analogue pain scales could be detected between the three groups. Application of intraarticular morphine did not reduce the amount of analgesics required for postoperative analgesia as compared to intravenous analgesia alone. Application of epidural morphine significantly suppressed beta-endorphine release, but did not significantly influence other stress hormones as compared to the control group. CONCLUSION: Epidural and intravenous analgesia after total knee arthroplasty are equivalent methods of pain relief. In major orthopaedic procedures, application of intraarticular morphine does not reduce analgesic requirements.  相似文献   
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Recently, there has been considerable interest and debate over the application of minimally invasive surgical approaches to primary total hip arthroplasty. The 2-incision technique employs intermuscular and internervous planes to gain access to the hip joint while minimizing the disruption of muscles and tendons. Through the anterior incision, the femoral neck is osteotomized and the head removed, followed by preparation and cementless reconstruction of the acetabulum. The posterior incision permits femoral preparation and reconstruction with a cementless stem. The potential benefits of this technique include decreased perioperative blood loss and pain, more rapid recovery of hip function and return to normal activity, a reduced length of hospital stay, and cosmetically appealing small scars. Other essential considerations include appropriate patient selection, adherence to surgical principles, and familiarity with specialized instruments and implants.  相似文献   
57.

Background and Objectives:

We examined 1-year functional and oncologic outcomes for robotic-assisted laparoscopic prostatectomy (RALP) from a single surgeon entering practice directly from fellowship training.

Methods:

We prospectively analyzed the first 100 RALPs performed by one fellowship-trained robotic surgeon. Data included resident involvement during the procedure, perioperative data, and surgical complications (scored using the Clavien grading system). Health-related quality of life (HRQOL) data were captured using the EPIC questionnaire at baseline (prior to surgery) and at 1-year follow-up.

Results:

Eighty-two patients (82%) had hospital stays of 2 days or less without any postoperative complications, urethral catheter removal was within 14 days of surgery, and none required readmission to the hospital. The overall positive margin rate was 21% (19% for patients with T2 disease). Clavien grades 1 through 4 complication rates, respectively, were 4%, 10%, 1%, and 1%. There were no deaths, reoperations, or bladder neck contractures. One patient (1%) required a blood transfusion within the 90-day perioperative period. At 1-year follow-up, 78% of patients reported wearing no pads; 41.3% of patients with baseline and 1-year follow-up data reported having intercourse.

Conclusions:

We provide baseline data pertaining to the morbidity, oncologic efficacy, continence results, and potency outcomes of new surgeons performing RALP.  相似文献   
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目的 报告成功实施腹腔镜迷你胃旁路术治疗单纯性肥胖并2型糖尿病病人1例。方法 第二军医大学附属长海医院微创外科于2007年11月对1例伴有2型糖尿病的单纯性肥胖症病人行腹腔镜迷你胃旁路术。结果 病人手术顺利,手术时间135min,术中出血20mL。术后30d内无手术并发症,随访30d,体重下降15kg,体重指数(BMI)减少4.9。术后第8天停用一切降糖药物,各项糖尿病检查指标均正常。结论 腹腔镜迷你胃旁路术是相对安全、简单的术式,近期减重效果良好,对2型糖尿病具有很好的治疗效果。  相似文献   
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