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41.
Cai M Langer EM Gill JG Satpathy AT Albring JC Wumesh KC Murphy TL Murphy KM 《Blood》2012,120(2):335-346
Myeloid ecotropic viral integration site 1 (Meis1) forms a heterodimer with Pbx1 that augments Hox-dependent gene expression and is associated with leukemogenesis and HSC self-renewal. Here we identified 2 independent actions of Meis1 in hematopoietic development: one regulating cellular proliferation and the other involved in megakaryocyte lineage development. First, we found that endogenous Mesp1 indirectly induces Meis1 and Meis2 in endothelial cells derived from embryonic stem cells. Overexpression of Meis1 and Meis2 greatly enhanced the formation of hematopoietic colonies from embryonic stem cells, with the exception of erythroid colonies, by maintaining hematopoietic progenitor cells in a state of proliferation. Second, overexpression of Meis1 repressed the development of early erythroid progenitors, acting in vivo at the megakaryocyte-erythroid progenitor stage to skew development away from erythroid generation and toward megakaryocyte development. This previously unrecognized action of Meis1 may explain the embryonic lethality observed in Meis1(-/-) mice that arises from failure of lymphatic-venous separation and can result as a consequence of defective platelet generation. These results show that Meis1 exerts 2 independent functions, with its role in proliferation of hematopoietic progenitors acting earlier in development from its influence on the fate choice at the megakaryocyte-erythroid progenitor between megakaryocytic and erythroid development. 相似文献
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Kobayashi H; Montgomery KT; Bohlander SK; Adra CN; Lim BL; Kucherlapati RS; Donis-Keller H; Holt MS; Le Beau MM; Rowley JD 《Blood》1994,84(10):3473-3482
Translocations and deletions of the short arm of chromosome 12 [t(12p) and del(12p)] are common recurring abnormalities in a broad spectrum of hematologic malignant diseases. We studied 20 patients and one cell line whose cells contained 12p13 translocations and/or 12p deletions using fluorescence in situ hybridization (FISH) with phage, plasmid, and cosmid probes that we previously mapped and ordered on 12p12-13. FISH analysis showed that the 12p13 translocation breakpoints were clustered between two cosmids, D12S133 and D12S142, in 11 of 12 patients and in one cell line. FISH analysis of 11 patients with deletions demonstrated that the deletions were interstitial rather than terminal and that the distal part of 12p12, including the GDI-D4 gene and D12S54 marker, was deleted in all 11 patients. Moreover, FISH analysis showed that cells from 3 of these patients contained both a del(12p) and a 12p13 translocation and that the affected regions of these rearrangements appeared to overlap. We identified three yeast artificial chromosome (YAC) clones that span all the 12p13 translocation breakpoints mapped between D12S133 and D12S142. They have inserts of human DNA between 1.39 and 1.67 Mb. Because the region between D12S133 and D12S142 also represents the telomeric border of the smallest commonly deleted region of 12p, we also studied patients with a del(12p) using these YACs. The smallest YAC, 964c10, was deleted in 8 of 9 patients studied. In the other patient, the YAC labeled the del(12p) chromosome more weakly than the normal chromosome 12, suggesting that a part of the YAC was deleted. Thus, most 12p13 translocation breakpoints were clustered within the sequences contained in the 1.39 Mb YAC and this YAC appears to include the telomeric border of the smallest commonly deleted region. Whether the same gene is involved in both the translocations and deletions is presently unknown. 相似文献
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目的 汉化癌症患者同伴支持量表,并检验其信效度。方法 通过正译、回译、文化调试和预调查对原量表进行汉化,形成中文版癌症患者同伴支持量表。于2021年3月—6月选取长沙市2所三级甲等医院的128例青年癌症患者进行问卷调查,分析量表的信效度;2021年7月—2022年3月选取该2所医院招募的241例患者进行问卷调查,用于验证性因子分析。结果 中文版癌症患者同伴支持量表包括3个维度、11个条目。量表水平的内容效度指数为0.948,条目水平的内容效度指数为0.714~1.000。探索性因子分析提取出3个公因子,各条目因子载荷为0.535~0.872,累计方差贡献率为69.64%,方程拟合良好。量表总的Cronbach’s α系数为0.923,折半信度为0.860。验证性因子分析结果 显示,模型拟合度良好。结论 中文版癌症患者同伴支持量表的信效度良好,适用于青年癌症患者同伴支持感的评估。 相似文献
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目的:目前临床进行隧道法舌根射频治疗时,其作用参数的设置仍缺乏统一的标准,故通过计算机三维重建射频损伤区域,分析猪舌根射频损伤体积与射频能量、时间的关系,从中得出应用舌根隧道法射频治疗的最佳作用能级和作用时间。
方法:实验于2006-06/2007-05在上海交通大学耳鼻喉科研究所完成。将36只实验用猪以射频作用能级1,2,3,4,5,6随机分成6组,每组6头猪,各个猪舌的作用时间分别设置为2,5,10,15,20,25s。用Coblation射频发生仪及Reflex55刀头进行猪舌根射频操作。射频作用后的舌根组织行连续冰冻切片,苏木精-伊红染色后,进行序列组织切片的全貌二维图像采集,对拟重建的结构进行边界提取和图像分割。将提取分割图像导入Image-Pro Solution图像处理软件,利用3D Constructor插件进行三维重建,并根据设定参数进行体积计算。用SPSS10.0统计学软件对所测数据进行统计学分析。
结果:①作用能级固定时,舌根组织射频损伤体积随时间延长而增大,符合Logarithmic回归曲线。②作用时间固定时,舌根组织射频损伤体积随能级增大而增大,符合直线回归。③射频损伤体积随能量增大而增加亦符合Logarithmic回归曲线。④Coblation射频治疗系统在能级6时,在作用10s之前,损伤体积随作用时间增加而迅速增加,其后变化趋势平缓,超过20s后损伤体积无显著增加。
结论:①舌根区域射频治疗时,舌根组织射频损伤体积与时间或能量呈Logarithmic曲线相关,与能级呈直线相关。②Coblation射频治疗系统在能级6时,最佳作用时间范围为10-20s。 相似文献
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Bernard SK Yeoh David McD Taylor Simone E Taylor 《Emergency medicine Australasia : EMA》2009,21(3):178-183
Objective: We aimed to evaluate a multifaceted education initiative designed to reduce the prophylactic use of metoclopramide. Methods: This was a pre‐ and post‐intervention trial undertaken in a single ED. All ED doctors and nurses were targeted. The intervention comprised a specifically designed, 19‐slide ‘e‐learning module’, accessible via the ED intranet, supplemented by in‐service training and a range of reminder techniques (posters, emails and drug room flyers). The primary end‐point was the proportion of patients administered metoclopramide prophylactically with their initial morphine dose. Data were collected on random samples of patients who received morphine, using explicit medical chart review. Results: Both pre‐ and post‐intervention periods were of 3 month duration. The charts of 146 cases were reviewed in each period. In the post‐intervention period: ? The proportion of patients administered metoclopramide prophylactically decreased from 22.6% to 4.1% (difference 18.5% [95% CI 10.3–26.7], P < 0.001) ? The proportion of patients administered metoclopramide appropriately (for known morphine sensitivity, established nausea and rescue anti‐emesis) rose marginally from 28.8% to 32.9% (difference 4.1% [95% CI ?7.2–15.4], P = 0.53) ? There was a 12.7% decrease in the number of ampoules of metoclopramide issued to the ED without a concurrent rise in the issue of other anti‐emetic drugs Conclusion: The education initiative resulted in a significant improvement in the evidence‐based use of metoclopramide. 相似文献
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An integrated review of the correlation between critical thinking ability and clinical decision‐making in nursing 下载免费PDF全文