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PURPOSE: Locally recurrent rectal cancer is associated with poor quality of life and has justified aggressive surgical and adjuvant approaches to control the disease. This study was designed to evaluate if the use of brachytherapy in association with wide surgical excision (debulking operation) can offer reasonable palliation for patients with locally recurrent rectal cancer. MATERIALS AND METHODS: Patients with biopsy-proven locally recurrent rectal cancer who were not candidates for intraoperative radiation therapy and who were previously considered as having unresectable tumors were included in the study and were followed-up from May 1981 to November 1990. All of them had undergone laparotomy and had either radical or debulking surgical resection performed. At the same time, brachytherapy was used with temporary or permanent implant of seeds of iridium-192 or iodine-125. RESULTS: Thirty patients were included. Patients ranged in age from 28 to 74 years, and 16 patients were female. No mortality was observed, and morbidity was low (small-bowel obstruction (1 patient), intestinal fistula (1 patient), and urinary fistula (1 patient). Histologic examination of the specimen showed gross residual disease in 67 percent of patients and microscopic disease in 25 percent of patients. Long-term follow-up was possible in 28 patients. Mean follow-up and local control were, respectively, 26.5 months and 37.5 percent for gross residual disease and 34 months and 66 percent for microscopic residual disease. Eighteen patients (64 percent) had locally recurrent rectal cancer under control at the time of the last follow-up, with seven patients (25 percent) having no evidence of local or distant recurrence. CONCLUSION: This is the first report of brachytherapy for locally recurrent rectal cancer. This appears to offer a therapeutic alternative to patients who are not candidates for intraoperative radiation therapy. Surgical morbidity and mortality are acceptable. Local control in 18 patients (64 percent) is comparable with intraoperative radiation therapy or more morbid surgical alternatives. Cancer-related deaths are most often related to disseminated disease, which suggests the need for systemic therapy in addition to brachytherapy.  相似文献   
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BACKGROUND Zinc is an essential trace element integral to many cellular and immune functions. Zinc deficiency is highly prevalent in patients with cirrhosis and related to disease severity.AIM To evaluate whether zinc supplementation improves clinical outcomes(disease severity and mortality) in patients with cirrhosis.METHODS This prospectively registered systematic review(PROSPERO reference: CRD42018118219) included all studies in Medline, Embase or Cochrane database with inclusion criteria of adult human studies, comparing zinc supplementation of at least 28 d with standard care or placebo in patients with cirrhosis. Mortality and clinical severity score data were extracted. Random effects meta-analyses compared mortality at 6 mo and 2 years. Risk of bias was assessed using the National Institutes of Health quality assessment tool.RESULTS Seven hundred and twelve articles were identified of which four were eligible. Zinc formulations and doses varied(elemental zinc 3.4-214 mg daily) for different intervention periods in patients with differing etiology and severity of cirrhosis. Two studies were considered to be at high risk of bias. There was no significant difference in 6-mo mortality between patients treated with zinc versus controls [risk ratio 0.98(0.90-1.05)]. Changes in severity scores were not reported in any study.CONCLUSION Zinc supplementation is not associated with reduced mortality in patients with cirrhosis. Findings are limited by the small number of eligible studies and significant heterogeneity in intervention and patient population.  相似文献   
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Norse Greenland has been seen as a classic case of maladaptation by an inflexible temperate zone society extending into the arctic and collapse driven by climate change. This paper, however, recognizes the successful arctic adaptation achieved in Norse Greenland and argues that, although climate change had impacts, the end of Norse settlement can only be truly understood as a complex socioenvironmental system that includes local and interregional interactions operating at different geographic and temporal scales and recognizes the cultural limits to adaptation of traditional ecological knowledge. This paper is not focused on a single discovery and its implications, an approach that can encourage monocausal and environmentally deterministic emphasis to explanation, but it is the product of sustained international interdisciplinary investigations in Greenland and the rest of the North Atlantic. It is based on data acquisitions, reinterpretation of established knowledge, and a somewhat different philosophical approach to the question of collapse. We argue that the Norse Greenlanders created a flexible and successful subsistence system that responded effectively to major environmental challenges but probably fell victim to a combination of conjunctures of large-scale historic processes and vulnerabilities created by their successful prior response to climate change. Their failure was an inability to anticipate an unknowable future, an inability to broaden their traditional ecological knowledge base, and a case of being too specialized, too small, and too isolated to be able to capitalize on and compete in the new protoworld system extending into the North Atlantic in the early 15th century.  相似文献   
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Streeter  RR; Presant  CA; Reinhard  E 《Blood》1977,50(3):427-432
In order to determine the prognostic significance of thrombocytosis in idiopathic sideroblastic anemia, the clinical courses of 17 patients were reviewed. Six patients (36%) had thrombocytosis, and none developed acute leukemia. Nine patients (53%) had normal platelet counts, and one developed acute leukemia. Two patients (12%) were thrombocytopenic, and one died of acute leukemia. There was little correlation between survival and platelet count. Sixty-three additional case reports of idiopathic sideroblastic anemia were collected from the literature. Analysis of those patients and the patients in the present study documented transformation to acute leukemia in 5 of 9 (56%) thrombocytopenic patients, 4 of 54 (7.4%) patients with normal platelet counts, and 0 of 17 patients with thrombocytosis (p less than 0.05). Therefore patients with idiopathic sideroblastic anemia and thrombocytosis appear to have a decreased likelihood of leukemic transformation.  相似文献   
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OBJECTIVE: To determine the incidence of urological complications of renal transplantation at one institution, and relate this to donor and recipient factors. PATIENTS AND METHODS: A consecutive series of 1535 renal transplants were audited, and a database of donor and recipient characteristics created for risk-factor analysis. An unstented Leadbetter-Politano anastomosis was the preferred method of ureteric reimplantation. RESULTS: There were 45 urinary leaks, 54 primary ureteric obstructions, nine cases of ureteric calculi, three bladder stones and 19 cases of bladder outlet obstruction at some time after transplantation. The overall incidence of urological complications was 9.2%, with that for urinary leak or primary ureteric obstruction being 6.5%. One graft was lost because of complications, and there were three deaths associated directly or indirectly with urological complications. There was no association with recipient age, cadaveric vs living-donor transplants, or cold ischaemic times before organ reimplantation, although the donor age was slightly higher in cases of urinary leak. There was no association with kidneys imported via the UK national organ-sharing scheme vs the use of local kidneys. The management of these complications is discussed. CONCLUSION: The incidence of urological complications in this series has remained essentially unchanged for 20 years. The causes of these complications and techniques for their prevention are discussed.  相似文献   
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The mechanism by which 7-ribosyl-3-deazaguanine [7R3DG, 6-amino-3-β-d-ribofuranosylimidazo[4,5-c]pyridin-4(5H)-one] exerts its antibacterial effect was examined. Escherichia coli was found to contain an enzyme that exhibited the properties of a nucleoside phosphorylase and that converted 7R3DG to 3-deazaguanine (3DG, 6-aminoimidazo[4,5-c]pyridin-4(5H)-one], but no mammalian system that was examined (Erilch ascites, rat liver and human liver) was able to convert 7R3DG to 3DG. The 3DG arising from the phosphorolysis of 7R3DG was converted to 3-deaza-GMP [3DGMP, 6-amino-l-β-D-riboluranosylimidazo [4,5-c]pyridin-4(5H)-one-5′-phosphate] by the guanine phosphoribosyltransferase present in E. coli. A strain of E. coli, resistant to 7R3DG, was found to lack this enzyme and, therefore, was unable to convert 3DG to 3DGMP.  相似文献   
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The MammoSite Radiation Therapy System (RTS) has become the most widely used brachytherapy method used in the treatment of breast cancer, due to its ease of use, short learning curve, and requirement of only one interstitial path through the breast skin. The dosimetry is simple, one source position in the middle of the MammoSite balloon catheter. The data on long-term complications, however are not available, though developing. Trials for DCIS are being developed, as well as a comparison trial to standard external beam radiation as well as other forms of accelerated partial breast irradiation (APBI).  相似文献   
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