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排序方式: 共有10000条查询结果,搜索用时 29 毫秒
941.
A Moberg Wing K Wing K Tholin R Sj?str?m B Sandstr?m G Hallmans 《European journal of clinical nutrition》1992,46(8):585-595
Exposure to cadmium via the diet is known to depend to a large extent on the intake of cereal grains, particularly the high-fibre fractions of wheat. Subjects with low iron status absorb more cadmium than those with better iron status. The purpose of the present study was to determine to what extent cadmium accumulation in human placenta is affected by the intake of grain fibre and maternal iron status during pregnancy. Thirty-nine pregnant women participated in the study. In each trimester the women were requested to complete a dietary history and to allow blood samples to be taken for haemoglobin, serum ferritin and serum thiocyanate determinations, the latter as a marker for smoking. At delivery the whole placenta was taken for the determination of the cadmium concentration. The 32 women who had serum thiocyanate levels less than 70 mumol/l, who had completed at least one dietary history and from whom a blood sample was obtained in the third trimester, were included in the final statistical analyses. In the group of women who consumed less than the median intake of grain fibre and had more than 15 micrograms ferritin/l serum in the third trimester, the placenta cadmium concentration was nearly half that in the placentae of women who had consumed more grain fibre or had lower iron status in late pregnancy. 相似文献
942.
943.
C R Eisendrath 《Transplantation proceedings》1992,24(5):2212-2214
944.
Fractures of the distal humerus. 总被引:4,自引:0,他引:4
We present a rational approach to the classification and surgical management of intraarticular fractures of the distal humerus. The fractures are classified on the basis of the surgical anatomy of the distal humerus, which is divided into two skeletal columns held together by the trochlea. The basic surgical aim is to restore all three elements with sufficient stability to permit functional movement. The surgical tactics are presented in detail. 相似文献
945.
LUMBOVERTEBRAL SYNDROME AFTER EXTRADURAL BLOOD PATCH 总被引:2,自引:1,他引:1
We describe a patient who developed an immobilizing lumbovertebralsyndrome after an extradural blood patch and who was hospitalizedwith a. suspected extradural abscess. An infectious aetiologyof the persistent backache could be excluded and the patientrecovered with analgesics and physiotherapy. The probable aetiologyis discussed. 相似文献
946.
947.
948.
949.
Maria A. Giovino Robert J. Hawley Matt W. Dickerson Roseann Glaser Deborah H. Meshulam Robert Ardtsini Margaret D. Rosa Rod L. Monroy 《Xenotransplantation》1997,4(2):112-119
Abstract: Establishment of mixed bone marrow chimerism in pig-to-primate transplantation, as a means of inducing specific immune tolerance, will require that both immune and nonimmune barriers be overcome. As a preliminary step in evaluating nonimmune barriers in this system, we have developed an in vitro model of engraftment in which long-term culture of porcine bone marrow-derived hematopoietic cells is supported on preformed primate bone marrow stromal layers. In the absence of cytokine supplementation, primate stromal cells were unable to support long-term porcine hematopoiesis in these cultures. Supplementation with porcine Steel Factor was required for long-term maintenance of hematopoietic progenitor cell content and total hematopoietic activity. Addition of porcine IL-3, in combination with porcine Steel Factor, increased long-term progenitor cell content and hematopoietic activity on primate stroma to levels comparable to that obtained in cultures on porcine stroma. The combination of porcine GM-CSF and Steel Factor increased progenitor cell content and hematopoietic activity early in the cultures, but had little effect in long-term cultures. The Steel Factor and IL-3 combination was species-specific in its action in these cultures, as the corresponding human cytokines were unable to effectively support long-term porcine hematopoiesis. Likewise, the combination of porcine cytokines had only minimal effects on long-term bone marrow culture of primate CD34+ cells I on primate stroma. 相似文献
950.
F. M. RAAPHORST R. LANGLOIS VAN DEN BERGH J. L. M. WAAIJER J. M. VOSSEN & M. J. D. VAN TOL 《Scandinavian journal of immunology》1997,46(3):292-297
Fetal B lymphocytes in mice and humans use a limited number of the available VH gene segments. Mouse fetal B cells primarily utilize 3' VH elements, suggesting that the localization of these elements determines their rearrangement frequency. The previously reported non-random usage of human VH genes has been more difficult to explain. In this study the authors analysed the expression of the most proximal 3' human VH element (VH 6) using a monoclonal antibody (JE-6). VH 6 expression was assessed in various B cell differentiation stages from fetal liver, bone marrow and spleen at 12–20 weeks of gestation. The authors demonstrate that the level of VH 6 expression does not exceed a stochastic usage frequency. This suggests that the localization of VH 6 does not significantly promote its expression during human fetal life, and that other factors must affect the usage of VH genes during human fetal development. 相似文献