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341.
We studied the effects of cis-retinoic acid (cisRA) on the clonogenic growth of samples of leukemic cells from 35 patients with acute nonlymphocytic leukemia (ANLL). We observed significant inhibition of leukemic colony growth in 17 samples by 10(-7) to 10(-6)M cisRA. However, we found that retinoid exposure resulted in striking stimulation of clonal growth in ten samples at the same drug concentrations. With the exception of cases with promyelocytic features, there was no morphologic or functional evidence that cisRA induced the leukemic blasts to differentiate. Both inhibition and stimulation were dose-dependent and observable at pharmacologically achievable levels of cisRA. Leukemic cells with monocytic features more frequently demonstrated a stimulatory response than did those without monocytic features. Depletion of T lymphocytes and monocytes did not alter the type of growth response. Assays for cellular retinoic acid- binding protein (CRABP) were performed on five samples (two with inhibitory growth responses, two with stimulatory responses, and one with no growth) and failed to reveal detectable levels of CRABP in any case. The addition of cisRA to liquid suspensions of leukemic cells produced no significant change in the number of viable cells. We conclude that the effects of cisRA on leukemic colony growth are not cytotoxic and not mediated by T lymphocytes, monocytes, or CRABP. More importantly, cisRA appears to enhance the growth of certain human leukemia cells in vitro. Taking into account the increasing use of retinoids in clinical trials for patients with leukemia, the latter findings may represent a significant cautionary note. 相似文献
342.
Graeme Browne RN MHN PhD Andrew Cashin RN MHN NP PhD Iain Graham RN RMN PhD Warren Shaw RN MHN GC Bus. Admin 《International journal of nursing practice》2013,19(5):539-545
The population of mental health nurses is ageing and in the next few years we can expect many to retire. This paper makes an argument for the employment of undergraduate nursing students as Assistants in Nursing (AINs) in mental health settings as a strategy to encourage them to consider a career in mental health nursing. Skill mix in nursing has been debated since at least the 1980s. It appears that the use of AINs in general nursing is established and will continue. The research suggests that with the right skill mix, nursing outcomes and safety are not compromised. It seems inevitable that assistants in nursing will increasingly be part of the mental health nursing workforce; it is timely for mental health nurses to lead these changes so nursing care and the future mental health nursing workforce stay in control of nursing. 相似文献
343.
血管内皮生长因子与基质金属蛋白酶2在血管瘤不同生长过程中的表达特征 总被引:3,自引:0,他引:3
目的:观察血管内皮生长因子与基质金属蛋白酶2在血管瘤不同分期中的表达。方法:取自承德医学院附属医院1998-01/2005-12期间血管瘤手术切除的标本共60例及正常带血管皮肤手术切除标本10例,患者家属知情同意。①实验分组:根据Mulliken标准进行病理诊断并分类,所有标本共分4组。增生组22例;退化组20例;退化完成组18例。另取10例正常带血管皮肤组织作为对照组。②采用免疫组织化学S-P法对各组标本的血管内皮生长因子、基质金属蛋白酶2进行染色。③实验评估:以正常血管上皮细胞或肿瘤细胞胞浆出现棕黄色颗粒为阳性,检测各组血管内皮生长因子与基质金属蛋白酶2的表达。结果:①随着血管瘤病理时期的变化,血管内皮生长因子与基质金属蛋白酶2出现明显不同的表达。②增生组血管内皮生长因子与基质金属蛋白酶2的阳性表达率明显高于其他各组,且随着血管瘤的退化,两者的阳性表达率逐渐下降,至退化完成期时与对照组几乎无差别。③血管内皮生长因子与基质金属蛋白酶2的表达呈正相关。结论:血管内皮生长因子与基质金属蛋白酶2在血管瘤的不同分期中起重要作用,其表达水平与血管瘤的病理分期有密切关系。 相似文献
344.
345.
目的:脐血处理的关键问题是提高干细胞的回收率及实现处理过程的标准化和可重复化,实验对此进行探讨,比较干细胞分离仪与传统羟乙基淀粉手工法分离脐血的效果。方法:实验于2006-12/2007-05在广州医学院附属市一人民医院完成。①脐血来源:39份脐血采自广州医学院附属市一人命医院妇产科健康顺产新生儿脐带,产妇均知情同意。随机数字表法分为仪器分离组17份、手工分离组22份。②实验方法:仪器分离组收集脐血称质量,计算体积,在开始处理前20min缓慢加入相当于20%脐血体积的60g/L羟乙基淀粉。仪器分离组按仪器要求自动分离,分离终体积20mL。手工分离组50g离心5min,压浆板压出全部血浆以及18mL红细胞移至无菌空袋,500g离心13min,自动压浆板压出血浆,保留20mL终体积样本。③实验评估:采用全自动计数仪进行检测有核细胞(白细胞)、红细胞数量。流式细胞仪分析CD34 含量。结果:采用干细胞分离仪处理浓缩脐血,有核细胞回收率为(89.7±3.4)%,CD34 细胞回收率为(98.8±5.1)%,红细胞去除率为(55.2±16.7)%,均比手工分离组分离效果好,差异有显著性意义(P<0.05或0.01)。同时,仪器分离组有核细胞回收率、CD34 细胞回收率的标准差均明显低于手工分离组(3.4vs.15.3;5.1vs.10.3)。结论:相比传统的羟乙基淀粉手工分离法,干细胞分离仪脐血分离浓缩效果理想,且结果标准误小,数据稳定。 相似文献
346.
Fonarow GC 《岭南心血管病杂志》1999,5(2):150
标题 用肼苯达嗪做直接血管扩张或用Captoprilr抑制血管紧张素转换酶对晚期心衰病死率的影响作者 FonarowGC,etal.JAmCollCardiol,1992,19:842(英文) 研究疾病:晚期心力衰竭。目的:比较血管紧张素转换酶抑制和直接血管扩张对晚期心衰预后的影响。 设计:随机式。病人资料:117例充血性心力衰竭者,NYHAⅢ级或Ⅳ级,休息时有血液动力学异常,为心脏移植做评估。随访:(8±7)个月。治疗方案:Captopril6.25mg渐增至100mg,每日4次,或者肼苯… 相似文献
347.
We previously showed the presence of receptors for granulocyte- macrophage colony-stimulating factor (GM-CSF) on tumor tissues and tumor cell lines that are derived from the neural crest. To determine whether normal neural cells express functional GM-CSF receptors, we isolated and analyzed primary rat brain cells, including microglia, astrocytes, and oligodendrocytes. Scatchard analysis of equilibrium binding of 125I-GM-CSF to primary rat oligodendrocytes showed an average of 1,110 GM-CSF binding sites per cell, with a kd of 20 pmol/L. In six separate experiments, no specific binding was detectable on the astrocyte population. Microglia were used in competitive binding experiments with oligodendrocytes, and addition of microglia did not increase the specific binding of labeled ligand to oligodendrocytes. In dose-response assays, we measured 3H-thymidine uptake in rat oligodendrocytes, microglia and control murine 32D cells stimulated with various concentrations of GM-CSF. Over concentration ranges of 0.025 to 1000 pmol/L, cell proliferation and peak 3H-thymidine incorporation was observed at approximately 30 pmol/L for both the control cells and the oligodendrocytes. However, the microglial cells did not proliferate in response to GM-CSF. These data indicate the presence of a functional receptor for GM-CSF on primary rat oligodendrocytes, and suggest that hematopoietic growth factors such as GM-CSF may play a role in nerve cell development, function, or response to injury. 相似文献
348.
Neil Keshvani Sonia Shah Iyanuoluwa Ayodele Karen Chiswell Brooke Alhanti Larry A. Allen Stephen J. Greene Clyde W. Yancy Windy W. Alonso Harriette GC Van Spall Gregg C. Fonarow Paul A. Heidenreich Ambarish Pandey 《European journal of heart failure》2023,25(9):1544-1554
Aims
Sex differences in long-term outcomes following hospitalization for heart failure (HF) across ejection fraction (EF) subtypes are not well described. In this study, we evaluated the risk of mortality and rehospitalization among males and females across the spectrum of EF over 5 years of follow-up following an index HF hospitalization event.Methods and results
Patients hospitalized with HF between 1 January 2006 and 31 December 2014 from the American Heart Association's Get With The Guidelines-Heart Failure registry with available 5-year follow-up using Medicare Part A claims data were included. The association between sex and risk of mortality and readmission over a 5-year follow-up period for each HF subtype (HF with reduced EF [HFrEF, EF ≤40%], HF with mildly reduced EF [HFmrEF, EF 41–49%], and HF with preserved EF [HFpEF, EF >50%]) was assessed using adjusted Cox models. The effect modification by the HF subtype for the association between sex and outcomes was assessed by including multiplicative interaction terms in the models. A total of 155 670 patients (median age: 81 years, 53.4% female) were included. Over 5-year follow-up, males and females had comparably poor survival post-discharge; however, females (vs. males) had greater years of survival lost to HF compared with the median age- and sex-matched US population (HFpEF: 17.0 vs. 14.6 years; HFrEF: 17.3 vs. 15.1 years; HFmrEF: 17.7 vs. 14.6 years for age group 65-69 years). In adjusted analysis, females (vs. males) had a lower risk of 5-year mortality (adjusted hazard ratio [aHR] 0.89, 95% confidence interval [CI] 0.87–0.90, p < 0.0001), and the risk difference was most pronounced among patients with HFrEF (aHR 0.87, 95% CI 0.85–0.89; pinteraction[sex*HF subtype] = 0.04). Females (vs. males) had a higher adjusted risk of HF readmission over 5-year follow-up (aHR 1.06, 95% CI 1.04–1.08, p < 0.0001), with the risk difference most pronounced among patients with HFpEF (aHR 1.11, 95% CI 1.07–1.14; pinteraction[sex*HF subtype] = 0.001).Conclusions
While females (vs. males) had lower adjusted mortality, females experienced a significantly greater loss in survival time than the median age- and sex-matched US population and had a greater risk of rehospitalization over 5 years following HF hospitalization. 相似文献349.
Padam Raj Joshi Sagar Babu Pandey Usha Manandhar Saroj GC Gopal Sedain 《Clinical Case Reports》2022,10(4)
Astroblastoma is a rare central nervous system tumor. We reported a case of a 24‐year‐old Nepalese woman with radiological features mimicking pilocytic astrocytoma which came out to be low‐grade astroblastoma in histopathological and immunohistochemistry examination after total excision of the tumor. 相似文献