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A technique for transperineal high-dose-rate (HDR) prostate brachytherapy and needle biopsy in a standard 1.5 T MRI scanner is demonstrated. In each of eight procedures (in four patients with intermediate to high risk localized prostate cancer), four MRI-guided transperineal prostate biopsies were obtained followed by placement of 14-15 hollow transperineal catheters for HDR brachytherapy. Mean needle-placement accuracy was 2.1 mm, 95% of needle-placement errors were less than 4.0 mm, and the maximum needle-placement error was 4.4 mm. In addition to guiding the placement of biopsy needles and brachytherapy catheters, MR images were also used for brachytherapy treatment planning and optimization. Because 1.5 T MR images are directly acquired during the interventional procedure, dependence on deformable registration is reduced and online image quality is maximized.  相似文献   
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OBJECTIVE: The indications for aortic root replacement in acute type A dissection are unclear. We reviewed the immediate and long-term outcome of consecutive patients in a series in which a low-threshold policy of composite aortic root replacement had evolved. METHODS: From a prospectively compiled aortic surgery database, we identified 162 patients who had either supracoronary interposition grafting, Group A (n=89), or composite root replacement, Group B (n=73) for acute type A dissection. Patients receiving total arch replacements were excluded. Operative and clinical details were analyzed and patient survival was compared to an age and gender matched census cohort. Need for reoperation on the proximal or distal aorta was also noted. Follow-up totaled 795.5 patient-years. RESULTS: Hospital mortality rates were identical in both groups (12.3%: 11 deaths in group A; 9 in group B). Chronic pulmonary disease, diabetes, malperfusion, hemodynamic compromise and aortic root dilatation were independent risk factors for hospital death. Actuarial survival estimates at 1, 5 and 10 years were 79% (71-88%), 64% (53-75%), and 55% (41-68%) for group A, and 79% (70-86%), 73% (62-83%), and 65% (52-78%) for group B (P=0.48). Age and operative patency of the ascending false lumen were independent risk factors for death after hospital discharge. Proximal aortic reoperation was required for four patients in group A and none in group B (P=0.085). CONCLUSION: A strategy of replacement rather than repair of the dissected aortic root for specific indications in type A dissection yielded high survival and low proximal reoperation rates. These results support an aggressive policy of composite root replacement in acute type A dissection.  相似文献   
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Urgent operation for acute transverse aortic arch dissection   总被引:1,自引:0,他引:1  
Surgical intervention is generally accepted for acute type A dissection, but little is published regarding therapy for acute dissection of the transverse portion of the aortic arch, though involved in approximately 15% of cases. Often, surgical treatment is withheld if aortography suggests a primary tear in the aortic arch. Similarly, resection is limited to the ascending aorta despite intimal tears within the transverse portion of the arch. This work reports a 9-year experience with a policy of emergency resection for all acute aortic dissections involving the aortic arch. Intensive "antiimpulse" therapy is instituted and aortic angiograms are obtained. Type A dissections are resected under moderate hypothermia and, if the primary tear extends into the arch or is not found in the ascending aorta, the arch is explored during a brief period of deep hypothermia and circulatory arrest. If necessary, the arch is replaced during circulatory arrest, the patient's head is packed in ice, steroids are administered, and a barbiturate coma is induced. If arch replacement is anticipated preoperatively, surface cooling is also employed. Sixteen acute (up to 14 days) and three subacute (15 to 28 days) transverse arch dissections were treated in this manner between May 1979 and May 1988, with four (21%) hospital deaths (25%, acute; 0%, subacute). Mortality was related to left main coronary dissection with extensive myocardial infarction in two of our four cases, a third death was related to persistent seizures in a renal transplant patient requiring hemodialysis who had lupus cerebritis, and the fourth resulted from rupture of the descending aorta 15 days after arch replacement.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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The aim of the present study was to compare the efficacy and the tolerability of three different antibiotic regimens for the treatment of acute otitis media in paediatric patients. 75 children, age range 6 months-6 years, divided into three groups, were involved in the study, each group consisting of 25 randomly assigned children (Group 1, amoxicillin 40 mg/kg tid per os for 10 days; Group 2, cefuroxime axetil 30 mg/kg bid per os for 10 days; ceftriaxone 50 mg/kg single-dose i.m.). No statistically significant difference was noted in the clinical efficacy among the different groups. Although amoxicillin is the drug of choice in paediatric otitis media, single dose ceftriaxone might be considered as an interesting alternative regimen when ease of administration and cost of therapy are considered.  相似文献   
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To evaluate the association of HLA types with Turkish patients with Graves' disease, HLA typing, clinical findings, and thyroid antibodies were correlated. The HLA types, clinical findings (ophthalmopathy and age at onset), and thyroid stimulating hormone (TSH) receptor (TRAb) and antithyroid microsomal antibodies (MAb) were analyzed. Seventy Turkish patients with Graves' disease and 306 control subjects were assessed. Serological HLA typing was performed in HLA A, B, C, DR, and DQ loci. There was a significantly increased prevalence of HLA B8, B49, DR3, DR4, and DR10 in Graves' disease. The association of Graves' disease with HLA DR3 was found to be less strong than previously described. The HLA DR4 antigen may contribute to the predisposition of Graves' disease in Turkey. The results suggest that HLA B7, B13, DR7, DQw2, and DQw3 may confer a protective effect for Graves' disease in Turkey. Patients carrying HLA B12, B18, and B44 haplotypes had a tendency to develop the disease at a later age. The difference from the other studies may be the result of the selection of the controls; in part, of the variability in serological typing reagents; and, also, of the rather weak HLA associations with the disease.This study was presented in part at the Annual Meeting of the National Endocrinology and Diabetes Association, Bursa, Turkey, May 25–28, 1992.  相似文献   
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A functional analysis of tumor-infiltrating lymphocytes (TILs) from renal cell carcinoma (RCC) and malignant melanoma was performed. TILs were expanded in recombinant interleukin-2 (50 U/ml) in Iscoves medium. Phenotypic and functional (cytolytic vs regulatory) analyses were carried out with the fresh and expanded TIL populations after 4 weeks in culture. Only one TIL population from an RCC case (out of six cases studied) was CD8+ and demonstrated MHC class I-restricted tumor-specific cytotoxicity against the autologous RCC target. TIL populations from the other five cases became predominantly CD4+ and they neither killed the respective autologous tumor cells nor killed the NK-sensitive target K-562 cells. When studied for other functions, two CD4+ TIL populations were found to suppress the lymphokine-activated killer cell response by peripheral blood lymphocytes (PBL) in coculture. Of these two, a TIL population from an RCC case (MJ TIL) was used to study the cellular and molecular mechanisms of suppression. The MJ TIL synthesized a supernatant factor that blocked activation of resting PBL as measured by the induction of high-affinity IL-2 receptor (IL-2R) when stimulated by phytohemagglutinin but did not down-regulate the fully expressed IL-2R on activated T cells. The suppression of high-affinity IL-2R induction on T cells did not result from tumor necrosis factor-alpha and beta or from transforming growth factor-beta as these cytokines were not detected in the cell-free supernatant from the MJ TIL culture. The supernatant factor also suppressed IL-2-mediated enhancement of cytotoxicity by natural killer (NK) cells without demonstrating direct toxic effect on the NK cells. Thus, when TIL are used for adoptive immunocytotherapy, it may be useful to fully characterize them functionally, in vitro.  相似文献   
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