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排序方式: 共有863条查询结果,搜索用时 390 毫秒
1.
The purpose of this study is to identify the local availability and trends in local availability of imaging technology and interpretation services in rural hospitals in the northwestern United States during the period between 1991 to 1994. Another objective is to describe hospital and community factors associated with the diffusion of image production and interpretation services. The information for this study was gathered through telephone surveys of rural hospital administrators in eight northwestern states in 1991 and 1994. The availability of magnetic resonance imaging (MRI) equipment, computed tomography (CT) scanners, ultrasonography equipment, and dedicated mammography equipment increased between 1991 and 1994. The increases in MRI units were primarily in mobile equipment, while ultrasonography and mammography equipment increases were primarily fixed hospital-based units. In 1994, image interpretation in the rural hospitals was provided by both primary care and radiology physicians. Forty-six (11.5%) of the rural hospitals had no on-site radiology services and only 73 (18%) had daily radiology services. Between 1991 and 1994, 12 hospitals gained at least once-a-week radiology services, but 24 lost all radiology services. Teleradiology availability more than doubled during the three years. Radiology technology has diffused widely into rural communities in this region of the United States at differing rates for large and small hospitals. Radiologists are available to these hospitals only 46 percent of the days each year, with more days of availability in the larger hospitals and fewer days in the smaller hospitals. Teleradiology capability is increasing more rapidly in the larger hospitals that have radiologists more readily available. 相似文献
2.
Anulus fibrosus in bulging intervertebral disks 总被引:1,自引:0,他引:1
In this investigation the association of radial tears of the anulus fibrosus and bulging of the intervertebral disk was studied. An index of disk bulging was measured in sagittal anatomic sections in 149 lumbar disks from 31 cadavers. The indexes of disk bulging were correlated with stages of disk development and the presence of an annular tear. The largest disk-bulging indexes were always associated with radial tears of the anulus. Eighty-four percent of the disks with radial tears had disk-bulging indexes greater than 2.5 mm. Most normal adult disks had an index of less than 2.5 mm. The results challenge the concept that the anulus fibrosus is intact in bulging disks, although ruptured in herniated disks. 相似文献
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DNA binding and heteromerization of the Drosophila transcription factor chorion factor 1/ultraspiracle.
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Christianson SW Greiner DL Deluca D Leif J Phillips NE Hayes SM Hayashi S Joliat MJ Lyons BL Shultz LD 《Journal of autoimmunity》2002,18(2):119-130
Defects in the gene that encodes SHP-1 protein tyrosine phosphatase result in multiple hematopoietic abnormalities and generalized autoimmunity in viable motheaten (me(v)) mice. These mice also exhibit early thymic involution and abnormalities in T cell development. Here, we describe the use of fetal thymic organ culture (FTOC) and bone marrow adoptive transfer to study the effects of SHP-1 deficiency on thymocyte development. Chimeric FTOC established with normal bone marrow placed onto deoxyguanosine-treated fetal thymic lobes or onto scid fetal thymic lobes generated T cells. Bone marrow from SHP-1-deficient me(v)/ me(v) mice generated decreased numbers of T cells in chimeric FTOC established using deoxyguanosine-treated thymi but generated normal numbers in chimeric FTOC established using scid thymi. However, scid fetal thymi seeded with me(v)/ me(v) bone marrow also exhibited morphological abnormalities and contained elevated numbers of macrophages. Addition of IL-7 to me(v)/ me(v) bone marrow-seeded scid FTOC led to increased cell numbers, particularly of macrophages. Intrathymic injection of IL-7 partially restored the ability of progenitor cells in me(v)/ me(v) bone marrow to populate the thymus of adoptive recipients. We conclude that abnormal T cell development in me(v)/ me(v) mice may in part be due to defects in the ability of bone marrow-derived accessory cells to provide bioavailable IL-7 to developing thymocytes. 相似文献
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Cytomegalovirus infection in infancy: virological and immunological studies 总被引:1,自引:2,他引:1
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R C Gehrz K M Linner W R Christianson A E Ohm H H Balfour 《Clinical and experimental immunology》1982,47(1):27-33
Immunological and virological studies on 18 infants with cytomegalovirus (CMV) infection were performed. Eleven of these infants were studied on multiple occasions over a period of 1 year. The patients were divided into three clinical groups based on the probable time of infection and the resulting variation in clinical presentation. General parameters of cell-mediated immunity as determined by E-rosette formation and lymphocyte proliferative responses to mitogens and antigens were found to be normal. Quantitation of CMV excretion in urine, CMV-specific immunofluorescent (IF) and complement-fixing (CF) antibody titres and CMV-specific cell-mediated immune responses were done on all patients at approximately monthly intervals. Throughout the study period all patients continued to excrete CMV despite the presence of high antibody titres to the virus. CMV-specific lymphocyte proliferative responses were absent or diminished in 15 of the 18 patients. The immunological and virological status of all patients was similar regardless of the clinical manifestation of infection. 相似文献
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