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51.
很久以来都认为遗传成分参与2型糖尿病(T2DM)的发病,但是有关遗传学上的发现一直进展缓慢,这是由于遗传成分的复杂性。有关糖尿病相关的各种表型的研究的大量资料提示,所谓的“T2DM”可能是许多疾病的统称,由于它们具有通常相互重叠的多种基本发病机制。因此,对曾抱有期望的T2DM的遗传学基础的寻求已经证明是很艰难的。  相似文献   
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Delfino  DV; Patrene  KD; Lu  J; Deleo  A; Deleo  R; Herberman  RB; Boggs  SS 《Blood》1996,87(6):2394-2400
Natural killer (NK) cells develop from the nonadherent cell component of NK long-term bone marrow (BM) cultures (NK-LTBMC). Because these nonadherent cells are depleted of mature NK cells and T cells, but appear to enriched for NK precursors, they were used as a starting population to begin to define the NK precursors that function in NK- LTBMC. As the stromal cell component of NK-LTBMC has been shown to support interleukin (IL)-2-induced, CD44 dependent, NK cell development from nonadherent NK precursors, NK-LTBMC stroma was used in a limiting dilution assay (LDA) to quantitate the precursors. NK-LTBMC in 96-well plates were irradiated (20 Gy) to kill hematopoietic cells (including the NK precursors), seeded with limiting dilutions of the cells to be quantitated, cultured with 500 U/mL IL-2 for 13 days and assayed for development of NK activity by adding 51Cr-labeled YAC-1 cells to the wells and evaluating the release of 51Cr after 4 hours. Flow cytometric analysis, sorting, and quantitation of the nonadherent cell component of NK-LTBMC showed that NK precursors were concentrated in the CD44neg/dim subset that comprised 10% of the "lymphoid" gated cells. When the CD44neg/dim subset was sorted from BM of mice treated with 5- fluorouracil (5-FU) day before (-1FUBM), there were about 30% T cells, but no NK-1.1+ cells. When the T cells were removed by sorting and the CD44neg/dim, alphabeta, gammadelta T-cell receptorneg (TCR-) subpopulation was seeded onto irradiated stroma with IL-2, they proliferated, developed NK activity, became NK-1.1+ and CD44bright and remained alphabeta, gammadelta TCR-. The frequency of NK precursors in this population as estimated from the LDA was about 1/500.  相似文献   
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H-kininogen (HK), a major factor involved in contact-phase activation, was recently immunolocalized on the external surface of human neutrophils. Experiments were, therefore, designed to consider the question of whether the complete assembly of contact factors occurs on the outer surface of the neutrophil membrane. By immunolocalization techniques, and using specific antibodies directed against the various contact factors, we now demonstrate that plasma prekallikrein (PK), factor XI (FXI), and factor XII (FXII) are present on the exterior face of the human neutrophil. Failure to localize HK, PK, or FXI by monoclonal antibodies directed to their reciprocal binding sites, and displacement of PK/FXI by peptide HK31, which mimics the relevant binding site(s) of HK, suggested that prekallikrein and FXI are anchored to the neutrophil membrane through attachment to the kininogen molecule. Probing of the kinin moiety by a specific antibody showed that kininogen molecules bound to the neutrophil cell membrane contain the kinin sequence, which can be released by plasma kallikrein or by tissue kallikrein. Our results led us to the novel conclusion that neutrophils provide a circulating platform for the components of the contact-phase system.  相似文献   
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Kiel  KD; Rademacker  AW 《Radiology》1996,198(1):279
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Allelic loss of the short arm of chromosome 1 has been observed frequently in oligodendroglioma (60-80%). We evaluated 177 oligodendroglial tumor samples and defined a consensus region of deletion of approximately 630 kb. This region contains a single gene, SHREW1, which encodes a novel transmembrane protein in adherens junctions. Whereas a mutation was not detected in the coding region of the SHREW1 gene in oligodendrogliomas, restoration of SHREW1 expression resulted in suppression of cell adhesion and migration. Thus, SHREW1 inactivation may play a role in the development of oligodendroglial tumors.  相似文献   
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