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71.
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B D Weiss 《The Journal of family practice》1988,26(3):273-280
For one year all pregnant women presenting to a family practice clinic for prenatal care were routinely tested for maternal serum alpha-fetoprotein levels (MSAFP). Unexpectedly, 14 (15.7 percent) of 89 tested patients had low MSAFP levels. All 14 pregnant women underwent appropriate diagnostic workups because of the low MSAFP level and were subsequently followed until delivery. Although the literature reports that low MSAFP levels are associated with chromosomal anomalies, none of the 14 women were delivered of infants with anomalies. Reasons for the unexpectedly high rate of abnormal MSAFP levels were investigated. Investigation revealed that normal values for MSAFP tests had been derived from testing performed on high-risk pregnant women who had an inherently higher rate of abnormal pregnancies and, apparently, a different range for normal MSAFP levels than a population of unselected family practice patients. The results of this study demonstrate that it may not be appropriate to apply diagnostic algorithms based on data derived in high-risk subspecialty clinics to unselected patients in a family practice. 相似文献
73.
Steven D Billings Shaun V Walsh Cyril Fisher Asma Nusrat Sharon W Weiss Andrew L Folpe 《Modern pathology》2004,17(2):141-149
Synovial sarcoma demonstrates epithelial differentiation, either by light microscopy (biphasic synovial sarcoma) or by immunohistochemical/ultrastructural methods only (monophasic) and poorly differentiated synovial sarcoma. Although the glands of synovial sarcoma are known to have tight junction-like structures, far less is known about junction formation in the spindled component of synovial sarcomas. Additionally, it is unknown whether the tight junctions of synovial sarcoma are normally constituted. The tight junction is a multiprotein complex consisting of numerous proteins that include ZO-1, claudin-1 and occludin. A total of 35 cases of synovial sarcoma (13 biphasic, 14 monophasic and eight poorly differentiated) were immunostained for ZO-1, claudin-1 and occludin using commercially available antibodies, heat-induced epitope retrieval and standard avidin-biotin technique. When available, corresponding electron micrographs were reviewed. For five cases, the presence of either an SYT-SSX1 (three cases) or SYT-SSX2 (two cases) gene fusion was known. Positive cases showed particulate membrane staining. The glands of biphasic synovial sarcomas expressed ZO-1 (13/13), claudin-1 (12/13) and occludin (11/13) in a manner identical to normal glandular epithelia, at the apical portion of the lateral membrane. The spindle cells of biphasic synovial sarcomas showed abnormal circumferential membranous expression of ZO-1 (12/13), claudin-1 (6/13) and occludin (3/13). Monophasic synovial sarcomas expressed ZO-1 in a circumferential pattern (13/14) but less often claudin-1 (4/14) or occludin (3/14). Poorly differentiated synovial sarcomas expressed ZO-1 (8/8) and claudin-1 (6/8) but only rarely occludin (2/8). By electron microscopy, recognizable tight junctions were seen only in glands. No correlation was seen between histologic subtype or fusion type and expression of tight junction proteins. We conclude that the glands of biphasic synovial sarcomas show well-organized, true epithelial tight junctions. In contrast, the spindled cells of all synovial sarcomas show significant abnormalities in the expression and localization of tight junction proteins, suggesting partial and/or aberrant epithelial differentiation. 相似文献
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The frequency of metaphases without a Philadelphia chromosome was determined in mitogen-stimulated cultures of peripheral blood mononuclear cells (PBMC) and purified T lymphocytes (93% CD2-positive) from a patient with chronic myelogenous leukemia (CML) for 28 years. The PBMC cultures contained few Ph-negative cells (8%), but they constituted 92% of the metaphases in T cell cultures, indicating few if any Ph-positive T cells in the patient's circulation. The results demonstrate that T cells derived from the leukemic clone may fail to replace the non-neoplastic population even when CML arises in childhood and the patient survives for many years. This raises questions concerning the normal role of the bone marrow as a source of T cells after infancy, and also whether Ph-positive lymphocytes may be at a disadvantage for growth. 相似文献
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This literature review emphasizes the importance of teacher training, teaching strategies, parental involvement, curricular concerns, administrative support, and social/cultural factors on the impact of nutrition education programs at the elementary school level. The characteristics, implementation, and effectiveness of selected elementary nutrition education programs are reviewed, and instructional methods and materials shown effective through research are identified and discussed. 相似文献