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曲鹏  张鸿  张正洪  方秀斌 《解剖科学进展》2006,12(3):215-218,i0004
目的探讨外源性神经生长因子(NGF)和降钙素基因相关肽(CGRP)对局灶性脑缺血再灌注后大鼠顶叶皮质神经元CHOP蛋白表达的影响及其作用机制。方法用线栓法制备大鼠大脑中动脉阻塞(MCAO)模型,应用免疫组织化学方法,免疫印迹法(W estern B lotting)测定CHOP蛋白表达;M etamoph图像分析系统对结果进行分析。结果假手术组大鼠顶叶皮质未见CHOP蛋白表达;缺血组CHOP蛋白在缺血再灌注后12 h明显表达,24 h达高峰,72 h显著下降,缺血组较假手术组CHOP蛋白表达显著增加(P<0.01);NGF组和CGRP组CHOP蛋白表达分别弱于缺血组(P<0.01);NGF和CGRP合用组CHOP蛋白表达明显弱于缺血组(P<0.01),也分别弱于NGF组和CGRP组(P<0.01)。结论NGF和CGRP能分别下调局灶性脑缺血再灌注大鼠顶叶皮质CHOP蛋白表达,联合应用则作用更强,二者对保护脑缺血神经元可能有协同作用。  相似文献   
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目的探讨促红细胞生成素(EPO)能否通过减轻内质网应激相关蛋白葡萄糖调节蛋白78(GRP78)和C/EBP同源蛋白(CHOP)的表达以及减轻横纹肌溶解致急性肾损伤。方法将SD大鼠随机分为4组:对照组(control,n=6)、单纯EPO组(EPO,n=18)、急性肾损伤组(AKI,n=18)和EPO干预组(AKI+EPO,n=18),EPO组、AKI组和AKI+EPO组又分为3个亚组,即1,6和24 h组(均为n=6)。在各自的时间点留取标本,检测血中尿素氮、肌酐和肌红蛋白水平;HE染色法观察肾脏病理;免疫组化观察GRP78和CHOP蛋白表达,实时荧光定量PCR检测GRP78和CHOP mRNA的表达。结果与对照组比较,AKI和AKI+EPO组大鼠尿素氮、肌酐和肌红蛋白水平升高,GRP78和CHOP蛋白及mRNA表达水平均显著上调(P0.05);AKI组肾脏结构出现损伤;与AKI组比较,AKI+EPO组6和24 h血肌酐水平,GRP78、CHOP蛋白和mRNA表达水平较同期均下降(P0.05)。结论 EPO可以通过影响横纹肌溶解致大鼠急性肾损伤时内质网应激相关蛋白的表达,发挥肾脏保护作用,其机制可能与调节未折叠蛋白反应有关。  相似文献   
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目的 观察以CEM (卡铂 +VP 16 +马法兰 )为预处理方案的自体外周血造血干细胞移植治疗晚期神经母细胞瘤患儿的毒性和疗效。方法 研究经大剂量放、化疗及手术治疗达完全缓解的IV期神经母细胞瘤患儿 6例 ,采用CEM预处理方案 (卡铂每日 4 2 5mg/m2 共 4d ,VP 16每日 338mg/m2 共 4d ,马法兰每日 70mg/m2 共 3d)的自体外周血造血干细胞移植 ,并依据Bearman标准对预处理毒性进行评价 ,对其造血重建、并发症及预后进行观察。结果 预处理后髓外毒性除 1例为I级肝损害外 ,主要表现在口腔粘膜 (I级 6例 )和胃肠道 (I级 5例 ,II级 1例 )损害。白细胞于移植后 3± 0 .5d达到 0 ,移植后 33± 3.1d稳定于 1× 10 9/L以上。除 1例患儿移植后 11个月颅内转移外 ,余 5例患儿均健康存活。随诊时间分别为 8、10、2 3、36及 4 8个月。结论 以CEM为预处理方案的自体外周血造血干细胞移植可以安全、有效的治疗IV期神经母细胞瘤。  相似文献   
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Objective: Magnesium sulphate is the preferred anticonvulsant used to prevent the development of fits in severe pre-eclampsia; we aim to compare between three different protocols of postpartum magnesium sulphate in the effectiveness of preventing the development of fits in severe pre-eclampsia.

Methods: Double-blind randomized controlled pilot trial, done in Cairo university hospital, Cairo, Egypt during 2013–2014, on 240 women with severe pre-eclampsia. Magnesium sulphate intravenous infusion was given in the postpartum period to all the patients, women were randomly allocated to group I (Single loading dose only), group II (12?h abbreviated protocol) or group III (24?h standard protocol) (n?=?80 in each group).

Results: There were no significant difference between the three groups as regards the incidence of eclampsia, elevated liver enzymes and low platelets syndrome, maternal ICU admission and; however The incidence of flushing was significantly higher in group III than group II and I (24 [30%] versus 12 [15%] versus 4 [5%]; p?<?0.001) respectively.

Conclusion: The pilot study demonstrates that the single-loading dose of postpartum magnesium sulphate is a promising alternative to the standard and the abbreviated protocol in preventing eclampsia; however, a large clinical trial is necessary to prove this.  相似文献   
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Cancer chemotherapy with the application of several drugs is studied. The negative and inhibiting effect of the tumour on normal cells is taken into account. Under certain hypotheses, we determine the optimal regimen that minimizes the tumour burden at the end of a fixed period of therapy while maintaining several normal cell populations above prescribed levels. More precisely, it is demonstrated that the optimal drug administration corresponds to the strategy of intensive chemotherapy.  相似文献   
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Allogeneic hematopoietic stem cell transplantation (alloHCT) is offered increasingly to elderly patients with hematologic malignancies. However, outcome data in those who are 70 years or older are limited, and no standard conditioning regimen has been established for this population. In this retrospective study we evaluated the outcome of 53 consecutive patients aged 70 years and older who underwent alloHCT with melphalan-based reduced-intensity conditioning (RIC) at City of Hope. Engraftment was prompt, with median time to neutrophil engraftment of 15 days. More than 95% of patients achieved complete donor chimerism within 6 weeks from HCT, consistent with the “semiablative” nature of this regimen. With a median follow-up of 31.1 months, the 2-year overall survival (OS), progression-free survival (PFS), and nonrelapse mortality (NRM) were 68.9%, 63.8%, and 17.0%, respectively. Cumulative incidence of relapse at 1 and 2 years was 17.0% and 19.3%, respectively. One hundred–day cumulative incidence of grades II to IV acute graft-versus-host disease was 37.7% (grades III to IV, 18.9%), and 2-year cumulative incidence of chronic graft-versus-host disease was 61.9% (extensive, 45.9%). The only significant predictor for poor OS was high/very high disease risk index. Transplant-related complications and morbidities observed here did not differ from the commonly expected in younger patients treated with RIC. In conclusion, alloHCT with a melphalan-based conditioning regimen is associated with acceptable toxicities and NRM, lower incidence of relapse, and favorable OS and PFS in patients aged 70 years or older.  相似文献   
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BEAM (carmustine [bis-chloroethylnitrosourea (BCNU)]-etoposide-cytarabine-melphalan) chemotherapy is the standard conditioning regimen for autologous stem cell transplantation (ASCT) in lymphomas. Owing to BCNU shortages, many centers switched to fotemustine-substituted BEAM (FEAM), lacking proof of equivalence. We conducted a retrospective cohort study in 18 Italian centers to compare the safety and efficacy of BEAM and FEAM regimens for ASCT in lymphomas performed from 2008 to 2015. We enrolled 1038 patients (BEAM =?607, FEAM =?431), of which 27% had Hodgkin lymphoma (HL), 14% indolent non-Hodgkin lymphoma (NHL), and 59% aggressive NHL. Baseline characteristics including age, sex, stage, B-symptoms, extranodal involvement, previous treatments, response before ASCT, and overall conditioning intensity were well balanced between BEAM and FEAM; notable exceptions were median ASCT year (BEAM?=?2011 versus FEAM?=?2013, P?<?.001), Sorror score ≥3 (BEAM?=?15% versus FEAM?=?10%, P?=?.017), and radiotherapy use (BEAM?=?18% versus FEAM?=?10%, P?<?.001). FEAM conditioning resulted in higher rates of gastrointestinal and infectious toxicities, including severe oral mucositis grade ≥3 (BEAM?=?31% versus FEAM?=?44%, P?<?.001), and sepsis from Gram-negative bacteria (mean isolates/patient: BEAM?=?.1 versus FEAM?=?.19, P?<?.001). Response status at day 100 post-ASCT (overall response: BEAM?=?91% versus FEAM?=?88%, P?=?.42), 2-year overall survival (83.9%; 95% confidence interval [CI], 81.5% to 86.1%) and progression-free survival (70.3%; 95% CI, 67.4% to 73.1%) were not different in the two groups. Mortality from infection was higher in the FEAM group (subhazard ratio, 1.99; 95% CI, 1.02 to 3.88; P?=?.04). BEAM and FEAM do not appear different in terms of survival and disease control. However, due to concerns of higher toxicity, fotemustine substitution in BEAM does not seem justified, if not for easier supply.  相似文献   
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