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991.
992.
Central areolar choroidal dystrophy (CACD) is a rare inherited retinal disease which causes progressive profound loss of vision in patients during their 4th decade. We have identified a Northern Irish family with 19 affected individuals in three living generations. We have performed a total genome search and established linkage of CACD in this family to chromosome 17p (multipoint Zmax = 5.65 at D17S938). The genes for phosphatidylinositol transfer protein (PITPN), retinal guanylate cyclase (GUC2D), beta-arrestin 2 (ARRB2), pigment epithelium-derived factor (PEDF) and recoverin (RCV1) map to this region and are candidate genes for retinal disease. Analysis of the coding region of the PITPN gene failed to reveal any mutation in this family.   相似文献   
993.
994.
Intracranial compliance in infants: evaluation with Doppler US   总被引:2,自引:0,他引:2  
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Uterine adnexal torsion: sonographic findings   总被引:5,自引:0,他引:5  
Acute torsion of the uterine adnexal structures (ovary and fallopian tube) is a recognized surgical emergency, but rarely has the diagnosis been made preoperatively on the basis of imaging studies. This report describes 16 cases in which the diagnosis was suggested preoperatively on the basis of sonography and subsequently confirmed at surgery. In all of the patients studied, a pelvic or pelvoabdominal mass was present on sonography. These masses had a sonographic texture ranging from cystic to solid, depending on the presence and extent of internal hemorrhage and/or stromal edema. In the majority of patients (13 of 16), adnexal torsion was associated with a preexisting cystic adnexal mass. Eight of these had thin internal septae. The severity of symptoms was variable and did not correlate directly with the sonographic features of the pelvic mass. Consideration of this entity in the proper clinical setting and with the typical sonographic findings will facilitate prospective recognition of adnexal torsion, thereby improving the chances for salvage of the involved adnexal structures.  相似文献   
998.
近红外光谱技术监测单肺通气时大脑氧合及血供的变化梁朝阳赵凤瑞酒古熏左焕宗作者单位:100029北京中日友好医院胸外科(梁朝阳、赵凤瑞、酒古熏),神经外科(左焕宗)从1995年9月1日至1996年3月31日,我们应用近年来发展的近红外光谱技术,利用含氧...  相似文献   
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CD34, which was first detected in hemopoietic and lymphopoietic progenitors, is a heavily glycosylated Type I transmembrane protein that does not share any significant similarity with other transmembrane proteins. Its functions are still unknown. Several monoclonal antibodies were raised against CD34, and at least 4 different epitopes could be recognized. CD34 expression is confined to a few cell lines, to 1-4% of adult bone marrow mononuclear cells (including marrow-repopulating cells, all multipotent and committed myeloid progenitors, B and T lymphoid precursors, osteoclast precursors, and most likely the precursors for stromal cells), and to less than 1% of peripheral blood mononuclear cells. In non-lymphohemopoietic tissues its expression is confined to endothelial cells and to some cells of the skin. In malignancies, CD34 expression is not fully elucidated. Immature hemolymphopoietic malignancies (namely acute leukemias) and the blast cells of chronic myeloid leukemia are frequently positive. Chronic lymphoproliferative disorders and lymphomas are negative. Among other tumors, only vascular derived tumors are positive. Clinical applications of CD34+ cells include autologous transplantation of putative CD34+ stem cells isolated by positive selection from the bone marrow, and transplantation of autologous peripheral blood stem cells, using the proportion and number of CD34+ cells as a guideline for the harvesting procedure.  相似文献   
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