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991.
BACKGROUND: Hepatitis C is the major cause of posttransfusion hepatitis. Blood components that are positive for antibody to hepatitis C virus (anti-HCV) can transmit posttransfusion hepatitis. STUDY DESIGN AND METHODS: To investigate the effect on posttransfusion hepatitis of screening blood donors with a second-generation test for anti-HCV, 249 transfusion recipients who underwent cardiovascular surgery were prospectively followed. Six recipients who were positive for anti-HCV before transfusion and 51 subjects with incomplete follow-up were excluded from this study. RESULTS: Eleven (13.8%) of 80 subjects who received unscreened blood had two successive serum alanine aminotransferase levels > 90 U per L. Seven (8.8% of total) developed anti-HCV and HCV RNA and two (2.5% of total) developed IgM antibody to cytomegalovirus (IgM anti-CMV). By contrast, 3 (2.7%) of the 112 subjects who received anti-HCV-screened blood had two successive serum alanine aminotransferase levels > 90 U per L. None of these three developed anti-HCV and HCV RNA, but two (1.8% of total) showed the development of IgM anti-CMV. The study shows that screening for anti- HCV in blood donors with a second-generation test almost abrogated posttransfusion viral hepatitis C. CONCLUSION: After anti-HCV screening, other body fluid-transmitted viruses such as CMV may become important in posttransfusion hepatitis.  相似文献   
992.
Ninety-nine consecutive patients with acute leukemia in first complete remission under age 50 (median age 27 years; age range 1 to 47 years) with a histocompatible sibling donor were treated with fractionated total body irradiation (1,320 cGy) and high-dose etoposide (60 mg/kg) followed by allogeneic bone marrow transplantation. Sixty-one patients were diagnosed with acute myelogenous leukemia (AML), 34 patients with acute lymphoblastic leukemia (ALL), 3 patients with biphenotypic acute leukemia, and 1 patient with acute undifferentiated leukemia. Thirty of the 34 patients with ALL had at least one of the following high-risk factors: age greater than 30, white blood cell count at presentation > 25,000/microL, extramedullary disease, certain chromosomal translocations, or the need for greater than 4 weeks of induction chemotherapy to achieve first complete remission. Cumulative probabilities of disease-free survival and relapse at 3 years were 61% and 12%, respectively, for the 61 patients with AML and 64% and 12%, respectively, for the 34 patients with ALL. By stepwise Cox regression analysis, significant prognostic variables for patients with acute myelogenous leukemia were the presence of acute graft-versus-host disease and increasing age, whereas for patients with acute lymphoblastic leukemia, significant variables were age and the development of cytomegalovirus-associated interstitial pneumonia. Complications related to graft-versus-host disease and relapse of leukemia were the major causes of death.  相似文献   
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994.
Chronic wounds remain a significant medical and financial burden in hospitals of today. A major factor in the transition from an acute to a chronic wound is its bacterial bioburden. Developments in molecular techniques have shown that chronic wounds remain colonised by many species of bacteria and that the bacteria within these chronic wounds exist in two forms. Treatments of chronic wounds have maintained a challenging field and significant ongoing research is being conducted. With the development of an in vitro wound model, we applied topical negative pressure (TNP) dressings to a spectrum of common bacterial biofilms found in chronic wounds and studied the synergistic efficacy between the application of TNP and silver‐impregnated foam against these biofilms. This synergistic response was seen within the laboratory strains of staphylococcal biofilms over a 3‐day treatment period but lost following the 5 days of treatment. However, combining topical pressure dressings and silver foam lead to a synergistic inactivation in Pseudomonas species over both 3‐day and 5‐day treatments.  相似文献   
995.
The design of medical devices is a complex and crucial process to ensure patient safety. It has been shown that improperly designed devices lead to errors and associated accidents and costs. A key element for a successful design is incorporating the views of the primary and secondary stakeholders early in the development process. They provide insights into current practice and point out specific issues with the current processes and equipment in use. This work presents how information from a user-study conducted in the early stages of the RAFS (Robot Assisted Fracture Surgery) project informed the subsequent development and testing of the system. The user needs were captured using qualitative methods and converted to operational, functional, and non-functional requirements based on the methods derived from product design and development. This work presents how the requirements inform a new workflow for intra-articular joint fracture reduction using a robotic system. It is also shown how the various elements of the system are developed to explicitly address one or more of the requirements identified, and how intermediate verification tests are conducted to ensure conformity. Finally, a validation test in the form of a cadaveric trial confirms the ability of the designed system to satisfy the aims set by the original research question and the needs of the users.  相似文献   
996.
997.
Despite decades of clinical data verifying the success of therapeutic approaches to human pituitary tumors, a significant number of tumors progress and can be life-threatening. The development of better therapeutic strategies for pituitary tumors is complicated by the relative scarcity of human pituitary material for basic experimentation. Human pituitary tissue was used to derive cell cultures, and a cell line, hPIT-1. Molecular and functional analyses were used to further characterize the cells as human pituitary explants in vitro. Functional analyses of the cell cultures indicated that the cells were tumorigenic and of human folliculostellate origin. hPit-1 cells revealed numerous abnormalities of ploidy. Molecular analyses indicated the absence of expression of the following pituitary hormones or hormone subunits by this culture: growth hormone, prolactin, ACTH, FSHbeta, LHbeta, THbeta, and p-glycoprotein. By contrast, the cells expressed uniformly high levels of human follistatin mRNA. Finally, the cells are moderately tumorigenic in immune-deficient mice. Although the precise molecular genetic mechanisms for tumorigenesis in the established cell culture are unknown, the cells serve as a future resource in the study of pituitary tumor initiation, progression, and response to therapy.  相似文献   
998.
Goals of work To assess complementary and alternative medicine (CAM) therapies being utilized by cancer patients during treatment and communication about CAM usage between the patient and physician.Patients and methods Newly diagnosed cancer patients receiving chemotherapy or radiation therapy were recruited to complete a CAM survey within 2 weeks after the termination of treatment. Patients were queried on which CAM modalities they utilized and whether or not they were discussed with either their oncologist or primary care physician.Main results Of the patients surveyed, 91% reported using at least one form of CAM. The most widely used forms of CAM were prayer, relaxation and exercise. CAM users tended to be women chemotherapy patients with at least a high school education. Of the patients using CAM, 57% discussed the use of at least one of these therapies with their oncologist or primary care physician. The most frequent CAM modalities discussed with at least one physician were diets, massage, and herbal medicine.Conclusions An overwhelming proportion of cancer patients are using CAM, particularly prayer, relaxation, and exercise. However, patients may not discuss the use of CAMs at all or fully with their physician; if they do, it is most likely to be their oncologist, but not about the most frequently used CAMs. Future research needs to assess effective ways for oncologists to gather information about CAM usage by patients during allopathic treatment and discern ways these therapies may enhance or interfere with traditional cancer treatments.  相似文献   
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1000.
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