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Studies of associations between perioperative blood transfusions and later recurrence of solid tumors have yielded conflicting results. A previous analysis of transfused patients suggested that recurrence was associated with transfusion of whole blood as opposed to red blood cell concentrates. Additional analyses were performed on patients with cancers of the colon, rectum, cervix, and prostate to determine if patients receiving whole blood, red blood cells only, or no transfusions had differing outcomes. Patients receiving 1 unit or more of whole blood had uniformly poor outcomes compared with nontransfused patients (p less than 0.001). In contrast, patients receiving only red blood cells had progressively worse recurrence and death rates with increasing numbers of transfusion, suggesting the presence of a dose-effect relationship. Employing multivariate techniques, blood transfusion of less than or equal to 3 units that included any whole blood were independently and significantly associated with earlier recurrence (p = 0.003) and death due to cancer (p = 0.02). Transfusions of less than or equal to 3 units of blood comprised solely of red blood cell concentrates were associated with no greater risk of recurrence than that seen in patients receiving no transfusion (p = 0.50). These results provide a potential explanation for the disparate results reported in studies of blood transfusion and cancer outcome. The marked difference in outcome seen between patients receiving a few units of red blood cells and comparable patients receiving even one unit of whole blood are consistent with the hypothesis that transfusion of stored blood plasma causes earlier tumor recurrence in some instances. Strategies for reducing these risks might include avoidance of whole blood transfusions when only 1-3 units are required, more conservative transfusion practice, use of autologous blood transfusions, and perhaps, use of red blood cells washed free of plasma and white cell debris. Clinical trials to test these hypotheses are urgently needed.  相似文献   
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Hip arthroplasty is a common orthopaedic procedure with proven long-term success and reliable results. A wide range of associated conditions may affect the outcome of the arthroplasty and the surgeon has to keep these in mind when planning the surgery. In this article, such situations are discussed and recommendations are drawn from the evidence available in literature.  相似文献   
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Naresh Agarwal  Rajnish Monga  A S Puri 《Indian journal of gastroenterology》2003,22(6):238; author reply 238-238; author reply 239
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We report the case of an 8-year-old boy with a parotid mass diagnosed to be a leiomyosarcoma. Considering the unresectable extent of the mass, the patient was subjected to radiotherapy. The patient developed distant metastasis following the course of radiotherapy and was put on chemotherapy. The child was lost to further follow up. To our knowledge, this is the first reported case in the English-language literature of such an entity in the pediatric age group.  相似文献   
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The L4 filtration membrane was used at our laboratory on 30 semen specimens (19 from suspected subfertile patients and 11 from fertile donors) to assess changes in semen quality after routine sperm washing and swim up versus filtration through the L4 membrane. Of these 30 samples 17 (11 suspected subfertile patients and 6 fertile donors) were chosen to evaluate differences in sperm fertilizing ability between the 2 sperm preparation methods. Liquified specimens were analyzed on a Cell Soft semen analyzer. Semen specimens were divided equally, and 1 aliquot was processed by sperm washing and the swim up technique and the other by filtration. In all subjects the results of semen analysis and the hamster-egg penetration test showed significant improvement in sperm quality and fertilizing ability after filtration through the L4 membrane. Sperm motility was 58% after the swim up technique compared to 79% after filtration (p less than 0.0001) and velocity was 47 mu. per second after the swim up method compared to 52 mu. per second after filtration (p less than 0.048). Penetration rate and penetration index also showed a significant increase after filtration over values for the swim up method. Our results demonstrate that sperm filtration through the L4 membrane provides results superior to those of the traditional swim up technique. Due to significant savings in time associated with its use the L4 membrane can be used during sperm processing for intrauterine insemination and in vitro fertilization procedures.  相似文献   
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