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Kaposi's sarcoma tumor cells preferentially express Bcl-xL.   总被引:10,自引:0,他引:10       下载免费PDF全文
Several recently identified proteins such as Bcl-2 and Bcl-x have been found to regulate programmed cell death (i.e., apoptosis). In this report, we examined the levels of expression of proteins that can either prevent apoptosis (i.e., Bcl-2 or the long form of Bcl-x, designated Bcl-x1) or promote apoptosis (i.e., Bax or the short form of Bcl-x, designated Bcl-xs) in proliferating benign and malignant endothelial cells (ECs). In normal skin with quiescent ECs, no detection by immunohistochemical staining was observed for Bcl-xL, Bcl-xs, or Bcl-2. However, in diseased skin samples that feature a prominent angiogenic response such as in psoriasis or pyogenic granulomas, the proliferating ECs markedly overexpressed Bcl-xL, with little to no Bcl-2. In an acquired-immune-deficiency-syndrome-related neoplasm, Kaposi's sarcoma, the spindle-shaped tumor cells also overexpressed Bcl-xL compared with Bcl-2. These in vivo studies were extended in vitro using cultured ECs and Kaposi's sarcoma tumor cells that were examined by flow cytometry and immunoblot analysis. Both cultured ECs and Kaposi's sarcoma tumor cells express significantly higher levels of Bcl-xL than Bcl-2. Such overexpression of cell survival gene products may contribute to prolonging the longevity of EC-derived cells in several different benign and neoplastic skin disorders that are characterized by a prominent angiogenic tissue response.  相似文献   
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SUMMARY. There are no current U.K. or international guidelines or regulations covering the production, processing and storage of haemopoietic cells such as to allow their engraftment following myeloablative therapy. This paper seeks to provide such guidelines. It enumerates how quality control and assurance can be applied to this area of transfusion medicine; procedural steps relating to bone marrow harvest on peripheral blood stem cell collection are outlined and recommended doses of nucleated cells suggested for both procedures. General specifications for identification, storage and transportation of bone marrow and peripheral blood stem cells are included and specific laboratory procedures related to the provision of haemopoietic cells for engraftment are outlined. Umbilical cord blood transplants and long-term bone marrow culture are alluded to but these are still in a research phase.  相似文献   
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We present two patients with angulated, proximal left circumflex lesions, one a chronic total occlusion and one an acute subtotal occlusion. In both cases, use of the deflectable tip Venture Catheter (Velocimed, Minneapolis, MN) facilitated guide wire passage and successful percutaneous coronary intervention (PCI) after prior attempts at guide wire passage with standard wires were unsuccessful.  相似文献   
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The purpose of this study is to evaluate the effectiveness of a shorter course of Dialectical Behavior Therapy (DBT) in enhancing treatment retention and reducing: urges to engage in non-suicidal self injury (NSSI), NSSI, suicide ideation, and subjective distress in borderline personality disorder (BPD). Twenty patients with BPD received a six-month course of Dialectical Behavior Therapy (DBT-B). DBT-B was delivered in the standard manner except for the shortened duration from one-year minimum to six months. All variables were measured at baseline, and at six months. Data were analyzed using paired t-tests. Treatment retention rate was 95%. Significant reductions were found in NSSI urges, NSSI, suicide ideation, subjective distress, depression, and hopelessness between baseline and six months. These results support the use of DBT-B in a six-month format when NSSI and suicidal behavior and ideation are the targeted behaviors. Target behaviors were reduced significantly and retention was extremely high in comparison to other interventions for this population. A large scale randomized controlled trial investigating its efficacy is warranted to determine if the results can be replicated and if improvement can be sustained.  相似文献   
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