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61.
Our purpose was to ascertain whether alcohol abuse is a risk factor for the development of hepatocellular carcinoma in urban southern Africa blacks and, if so, to relate alcohol consumption to other possible risk factors such as persistent hepatitis-B-virus infection, smoking, male sex, in this subpopulation. A prospective, hospital-based, case-control format involving 101 patients with hepatocellular carcinoma and 101 controls was used. The mean age of the patients was 53.7 +/- 1.85 years and the male:female ratio 3.2:1. An increased risk was found, but only in urban men over the age of 40 years who habitually drank more than 80 g of ethanol daily. The risk remained after adjusting for chronic hepatitis-B infection, smoking, and sex (odds ratio 4.4, 95% confidence interval 1.3 to 16.6; p = 0.003). Smoking proved not to be a risk factor, either alone or in concert with alcohol consumption. Hepatitis-B infection was confirmed as a major risk in younger men and in women, but in urban men over the age of 40 years alcohol abuse was a greater risk. Current hepatitis-B infection and alcohol abuse were additive risks.  相似文献   
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Candida albicans vertebral osteomyelitis is rare. Three cases are presented. Without antifungal treatment, they developed spinal collapse and neurological deterioration within 3–6 months from the onset of symptoms. There was a delay of 4.5 and 7.5 months between the onset of symptoms and surgery. All patients were managed with surgical debridement and reconstruction and 12-week fluconazole treatment. The neurological deficits resolved completely. The infection has not recurred clinically or radiologically at 5–6 years follow-up. Although rare, Candida should be suspected as a causative pathogen in cases of spinal osteomyelitis. Without treatment the disease is progressive. As soon as osteomyelitis is suspected, investigations with MRI and percutaneous biopsy should be performed followed by medical therapy. This may prevent the need for surgery. However, if vertebral collapse and spinal cord compression occurs, surgical debridement, fusion and stabilisation combined with antifungal medications can successfully eradicate the infection and resolve the neurological deficits.  相似文献   
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BACKGROUND AND PURPOSE: Helical tomotherapy can eliminate the need for junction lines. The goal of this study is to evaluate tomotherapy in the delivery of CSA radiation and measurement of plan quality using physical parameters in comparing conventional (CSA-RT) and helical tomotherapy (CSA-TOMO) plans. PATIENTS AND METHODS: CSA-TOMO and CSA-RT plans were created for dosimetric comparison. Integral dose values were calculated. The ratios D50% (dose received by 50% of the organ at risk's volume) and D10% (dose received by 10% of the organ at risk's volume) were calculated representing large volumes and small volumes of organs at risk receiving significant dose. RESULTS: When considering D50% and D10%, CSA-TOMO has a dosimetric advantage over CSA-RT for most organs at risk. The body integral dose was higher for the CSA-TOMO plan by approximately 6.5%. CONCLUSIONS: Tomotherapy is a feasible alternative for treatment of CSA. Analysis shows that tomotherapy improves dose ratios over conventional radiation for most organs at risk. The impact of a small increase in whole body integral dose is unknown. Long-term follow-up will be needed to answer this question as others have argued of the possibility of increased risk of secondary malignancies due to delivery of radiotherapy with IMRT.  相似文献   
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BACKGROUND AND OBJECTIVES: Inguinal hernia repair is one of the most frequently performed pediatric surgical operations. Several pediatric laparoscopic inguinal hernia repair techniques have been introduced. But debate is unresolved regarding the feasibility of laparoscopy for treating pediatric inguinal hernias. METHODS: A retrospective cohort study enrolled 33 patients who underwent congenital inguinal hernia repair by either the new laparoscopic flip-flap technique or conventional open repair. Patients were divided into 2 groups according to the type of surgery: Group A included those who underwent the new laparoscopic technique, and Group B included those who underwent conventional open repair. RESULTS: Group A comprised 15 patients (mean age, 39 months), and group B comprised 18 (mean age, 44 months). Mean operative time was 47.5 minutes for Group A versus 27.5 minutes for Group B. Intraoperative complications for Group A included 1 case (7%) of vas deferens injury, and 3 cases (20%) in which the flaps were torn during suturing. In Group B, no intraoperative complications were encountered. In both groups, the mean postoperative hospital stay was 5.5 hours. Postoperative follow-up of 3 months revealed recurrence in 4 patients in Group A (27%), while there were no recurrences in Group B. CONCLUSION: Our preliminary experience shows unsatisfactory outcomes with laparoscopic flip-flap hernia repair in children. In spite of advancement in the application of laparoscopy in pediatric surgery, conventional open hernia repair is still the gold standard for children, in our experience. Future studies with more numbers and longterm follow-up should be conducted.  相似文献   
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The inducible co-stimulatory molecule (ICOS) has been shown to play a critical role in T-cell activation and differentiation, and the regulation of alloimmune responses in vivo. Using an MHC class II mismatched model of CD4(+) T-cell-mediated rejection, we found that treatment of mice with DST and ICOS-B7h blockade induced long-term skin allograft survival and donor-specific transplantation tolerance. ICOS blockade, either during antigen priming or during the effector phase, previously shown to alter the outcome of the immune response, had a similar effect on graft survival. DST and anti-B7h mAb reduced the frequency of IFN-gamma-producing allospecific cells but did not produce deviation to a T(H)2 phenotype. In an adoptive transfer model using ABM TCR transgenic mice directly reactive to I-A(bm12), DST and anti-B7h mAb reduced the number of allospecific CD4(+) T cells and increased CD4(+) T-cell apoptosis. These data demonstrate that DST and anti-B7h mAb induces transplantation tolerance to MHC class II mismatched skin grafts by a reduction of the alloreactive clone size that is, at least in part, dependent on apoptosis of host alloantigen-specific CD4(+) T cells.  相似文献   
67.
Over the past decade the practice of acute resuscitation and its monitoring have undergone significant changes. Utilization of noninvasive mechanical ventilation, goal-directed therapy, restricted fluid volume, blood transfusion and minimally invasive technology for monitoring tissue oxygenation have changed the practice of acute resuscitation. Early diagnosis and definitive treatment of the underlying cause of shock remains the mainstay for survival after successful resuscitation. Patient-centered outcome end-points, in addition to survival, are being utilized to appraise the effectiveness of treatment. Application of medical ethics to the ever changing practice of acute resuscitation has also become a societal expectation.  相似文献   
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The overlooked, retained double J stent   总被引:2,自引:0,他引:2  
A series of 4 patients with long overlooked, retained ureteral stents is presented to illustrate the variable, unpredictable, and at times, hazardous course of such patients. These cases are cited to re-emphasize the need for careful documentation, observation, and follow-up of patients in whom stents are placed.  相似文献   
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