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BACKGROUND: Since screening for antibody to hepatitis C virus (HCV) was introduced in 1990, posttransfusion hepatitis has been reduced to nearly background levels. This has led to reconsideration of the value of testing donated blood for elevated alanine aminotransferase (ALT). The contribution of ALT testing in detecting seronegative infection was evaluated by the performance of polymerase chain reaction (PCR) for hepatitis B virus (HBV) or HCV in plasma from ALT-elevated blood units. STUDY DESIGN AND METHODS: Testing was performed on 375 units of plasma, derived from an equivalent of 47,500 blood donations, with a highly sensitive hemi-nested PCR procedure. Using a triplet of primers directed at the conserved regions of HBV DNA and 5'-noncoding regions of HCV RNA, the hemi-nested PCR assay can reliably amplify 10 viral molecules to levels detectable in ethidium bromide-stained agarose gels. Pools of plasma from groups of four donors were screened with hemi-nested PCR. For any reactive pools, the plasma from individual donors was retested twice on different aliquots. RESULTS: Two of 375 units, both with midrange ALT elevation, were repeatedly reactive in hemi-nested PCR (one each for HBV DNA and HCV RNA). However, samples from the two suspect donors tested 9 and 5 months later revealed no seroconversion, elevated ALT, or viral genomes in hemi-nested PCR. CONCLUSION: The lack of confirmed HBV or HCV infection in this study representing an estimated 47,500 voluntary blood donations suggests that routine ALT testing for further prevention of posttransfusion hepatitis after exclusion of HBV- and/or HCV-seropositive blood may be superfluous.  相似文献   
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Open-ended interviews with 107 patients documented specific patient expectations of radiologic procedures during which there was no direct radiologist-patient interaction. Patient expectations could be classified into those related to the facility and those related to interactions with radiology staff. Among facility-related expectations, waiting time far outweighed all other concerns. Interpersonal skills were the predominant expectation of radiology staff. The role of the radiologist in fulfilling patient expectations was less clear. Only 10% of unprompted patients cited the radiologist as a factor in their expectations. When patients were specifically prompted to discuss the radiologist's role, communication skills, accuracy of interpretation, and interpersonal skills were the predominant concerns.  相似文献   
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Myocardial tagging in polar coordinates with use of striped tags   总被引:1,自引:0,他引:1  
Bolster  BD  Jr; McVeigh  ER; Zerhouni  EA 《Radiology》1990,177(3):769-772
Regional deformation abnormalities in the heart wall provide a good indicator of ischemia. Myocardial tagging with magnetic resonance imaging is a new method of assessing heart wall motion during contraction. Current methods of myocardial tagging either do not provide two-dimensional information or lack a coordinate system well adapted to the morphology of the heart. In this article, the authors describe a new tagging method that provides a true polar coordinate system, with both radial and angular dimensions. This is accomplished with use of a section-selective version of spatially modulated magnetization resulting in striped tags (STAGs). These STAG planes are placed in the myocardium in a star pattern so that they intersect on the long axis of the heart and stripes appear through the width of the heart wall. In the short-axis view during contraction, rotation around the long axis yields angular information such as shear and twist, while separation of the stripes within the myocardium permits measurement of radial thickening. Therefore, this method provides a coordinate system for calculating two-dimensional strain that is adapted to the morphology of the left ventricle.  相似文献   
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Malignant melanoma (MM) is a highly aggressive neoplasm with a growing worldwide incidence. It is not uncommon that the disease is already metastatic at the time of the first diagnosis. Regional lymph nodes and skin are the first and most common metastatic sites, followed by distant visceral sites (lungs, liver, and central nervous system) and bone. In this clinical setting, fine-needle aspiration (FNA) often represents the first diagnostic approach. FNA is a useful tool to obtain a rapid and accurate diagnosis, in conjunction with ancillary techniques and molecular analysis, as recommended by recent guidelines. The aim of this review was to describe the cytomorphology, immunocytochemical tools, and molecular tools used for the diagnosis of MM metastases on FNA.  相似文献   
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Data are reported from a larger study of perceptions of locus of control and value of pressure ulcer prevention to show the position of orthopaedic nurse control beliefs, their departmental knowledge level, and their value of pressure ulcer prevention relative to that of staff in other specialties. The survey population consisted of trained and assistant nursing staff in both hospital and community settings of a rural Health Service Trust. Overall results showed that key personnel, such as sisters, were significantly associated with prevalence, in that the more they believed they controlled pressure sore prevention, rather than the patient, the higher the prevalence. This has been explained using locus of control typology. The more it was thought that fate controls pressure sore prevention, the lower the departmental prevalence. Further, beliefs about specific conditions (e.g. pressure ulcer prevention) may be less important than generalized beliefs about control in terms of reducing prevalence.It is suggested that the study is replicated and refined, and that the value of pressure sore prevention needs raising. Certain types of attitudes amongst staff may be unhelpful in a broader range of conditions and outcomes. There may be a need to change control expectations of groups of personnel in order to protect patients.  相似文献   
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Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mainly invades the respiratory system, but may also cause various cardiovascular complications. We report a rare case of myocarditis associated with SARS-CoV-2 infection. A 61-year-old man was admitted to the hospital with a positive nucleic acid test for SARS-CoV-2. A sudden increase in troponin level (up to .144 ng/mL) was observed on the 8th day after admission. He developed symptoms of heart failure and progressed rapidly to cardiogenic shock. Echocardiography on the same day showed reduced left ventricular ejection fraction, reduced cardiac output, and segmental ventricular wall motion abnormalities. Takotsubo cardiomyopathy associated with SARS-CoV-2 infection was considered based on the typical echocardiography findings. We immediately started veno-arterial extracorporeal membrane oxygenation (VA-ECMO) treatment. The patient was successfully withdrawn from VA-ECMO after 8 days following recovery of ejection fraction to 65% and all indicators qualifying the withdrawal criteria. Echocardiography plays an important role in dynamic monitoring of cardiac changes in such cases and can help determine the timing of extracorporeal membrane oxygenation treatment and withdrawal.  相似文献   
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