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61.
目的 :研究体外制备的糖基化产物引起肾脏的自由基损伤。方法 :给正常大鼠静脉注射体外制备的糖基化血清蛋白 (GSP) 2个月 ,观察 GSP对肾脏自由基代谢的影响。结果 :GSP处理的大鼠肾脏糖基化终末产物 (AGE)浓度和 NBT染色强度明显高于对照组。与对照组比较 ,接受 GSP的大鼠肾脏超氧化物歧化酶 (SOD)和过氧化氢酶 (CAT)活性明显降低 ,尿液脂质过氧化物 (MDA)水平显著升高。结论 :外源性 GSP可引起正常大鼠肾脏自由基代谢紊乱 ,糖基化产物的致病作用部分是由氧化应激损伤引起的  相似文献   
62.
目的探讨经肺热稀释技术对不同原因急性肺损伤(ALI)血管外肺水(EVLW)测定的准确性。方法18只杂种犬随机分为正常组、外源性急性肺损伤组和内源性急性肺损伤组,每组6只,通过静脉注射油酸制备外源性ALI模型,气管内注入十六烷磺基丁二酸钠盐制备内源性ALI模型,然后分别向肺内灌注一定量的生理盐水,采用经肺热稀释法在灌注的前后测定EVLW,观察灌注前后EVLW变化与所灌注生理盐水量之间相关性。结果正常肺组织EVLW含量为(254.5±413.0)ml,肺泡灌注前后EVLW的变化与实际肺泡灌注生理盐水量之间具有良好的相关性(r=0.986,P〈0.01);外源性ALI组EVLW含量为(483.3±11.5)ml,与正常组比较差异有统计学意义(P〈0.01),ALI组肺泡灌注前后EVLW的变化与实际肺泡灌注生理盐水量之间也具有良好的相关性(r=0.978,P〈0.01)。内源性ALI组EVLW含量为(526.2±12.9)ml,与正常组比较差异有统计学意义(P〈0.01)。肺内源性ALI组肺泡灌注前后EVLW的变化与实际肺泡灌注生理盐水量之间具有较好的相关性(r=0.890,P〈0.01),但不如外源性ALI组相关性高。结论经肺热稀释技术对EVLW的监测具有良好的准确性,但不同原因导致的EVLW增加的监测准确性不同。  相似文献   
63.
目的 优选雷公藤涂膜剂基质的组成和配比。方法 采用正交试验法,以外观质量、成膜时间为指标,确定基质中不同辅料的最佳配比。结果 以聚乙烯醇-124、CMC-Na、甘油比例为4∶1∶2制得的涂膜剂最稳定。结论 优选得到的配方设计合理,制备工艺简单,质量可控,可以为工业生产提供理论基础。  相似文献   
64.
目的总结胸腺扩大切除术治疗重症肌无力(myasthenia gravis,MG)的外科治疗经验,探讨MG外科治疗效果。方法回顾性分析我院1996年6月至2017年10月期间527例行胸腺扩大切除术的MG患者临床病例资料,其中男242例,女285例;年龄5~77岁,平均(52.6±13.7)岁。病程12天~18年。合并甲状腺功能亢进症22例,纯红细胞再生障碍性贫血7例,甲状腺机能减退症、肠激惹症、风湿性关节炎、强直性脊柱炎和血小板减少综合征各1例。改良OssermanⅠ型272例,Ⅱa型72例,Ⅱb型78例,Ⅲ型81例,Ⅳ型24例。所有患者肌疲劳试验、新斯的明试验阳性,胸部CT检查明确诊断。总结围手术期相关资料及术后随访情况。结果围手术期死亡3例,均为胸腺瘤合并MG,其中OssermanⅢ型MG 2例、Ⅳ型MG 1例。术后肌无力危象15例,其中OssermanⅡb型2例、Ⅲ型11例、Ⅳ型2例,气管切开7例。血浆置换70例,并发低渗综合征、下肢静脉血栓各2例。术后病理诊断胸腺增生293例(55.60%)、胸腺瘤207例(39.28%)、胸腺囊肿24例(4.55%)和胸腺萎缩3例(0.57%)。随访378例,平均随访(85.9±58.5)月;MG完全缓解、部分缓解、无变化和恶化患者分别为135例(35.71%)、192例(50.79%)、41例(10.85%)和10例(2.65%)。完全缓解率OssermanⅠ>Ⅱa>Ⅳ>Ⅱb>Ⅲ型,恶化率OssermanⅢ>Ⅳ>Ⅰ型。OssermanⅠ型外科治疗无效18例,术前病程>5~10年;恶化1例,为应用电视胸腔镜胸腺切除的眼肌型MG患者,遗留胸腺左叶未切除,6年后发展为重度全身型,再次手术切除遗留的左叶胸腺,证实左叶胸腺代偿性肥大增生。恶化患者中死亡6例,均为胸腺瘤合并MG,其中OssermanⅢ型5例、Ⅳ型1例;死亡原因为肌无力危象3例,快速停服溴吡斯的明3个月后突发呼吸骤停猝死2例,胆碱能危象1例。结论规范的胸腺扩大切除是治疗MG的有效方法,眼肌型MG尽早手术可有效降低其全身性转化风险。OssermanⅡb型以上MG易发生肌无力危象,围手术期采取综合处理措施有助于降低MG相关风险。重症术后远期可反复发生肌无力危象,须规律用药,并采取MG综合治疗措施。  相似文献   
65.
Coronavirus disease (COVID-19) was declared a pandemic by the World Health Organization on 11 March 2020 because of its rapid worldwide spread. In the operating room, as part of hospital outbreak response measures, anesthesiologists are required to have heightened precautions and tailor anesthetic practices to individual patients. In particular, by minimizing the many aerosol-generating procedures performed during general anesthesia, anesthesiologists can reduce exposure to patients’ respiratory secretions and the risk of perioperative viral transmission to healthcare workers and other patients. To avoid any airway manipulation, regional anesthesia should be considered whenever surgery is planned for a suspect or confirmed COVID-19 patient or any patient who poses an infection risk. Regional anesthesia has benefits of preservation of respiratory function, avoidance of aerosolization and hence viral transmission. This article explores the practical considerations and recommended measures for performing regional anesthesia in this group of patients, focusing on control measures geared towards ensuring patient and staff safety, equipment protection, and infection prevention. By doing so, we hope to address an issue that may have downstream implications in the way we practice infection control in anesthesia, with particular relevance to this new era of emerging infectious diseases and novel pathogens. The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is not the first, and certainly will not be the last novel virus that will lead to worldwide outbreaks. Having a well thought out regional anesthesia plan to manage these patients in this new normal will ensure the best possible outcome for both the patient and the perioperative management team.  相似文献   
66.
中医证素辨证研究概况   总被引:5,自引:0,他引:5  
朱文锋教授经过32年的深入研究,创立了"证素辨证"新体系。随着证素辨证这一新型辨证方法的提出,关于证素的相关研究就迅速成为中医学基础与临床研究的一大热点。证素辨证具有良好的临床和科研的兼容性、坚实的理论基础和日益丰富的应用经验,其未来前景不可限量。  相似文献   
67.
C/EBP is a sequence-specific DNA-binding protein.In order to identify its distribu-tion,localization and function,immunocytochemical technique(ABC method)was done usinganti-C/EBP polypeptide antibodies 1103~#,425~# in liver specimens from 20 normal adult,5neonatal,6 patients with hepatitis,25 patients with liver cirrhosis,80 patients with hepatocellu-lar carcinoma(40 cases were associated with surrounding nontumorous tissues)and 26 patientswith cholangiocarcinoma(15 cases were associated with surrounding nontumorous tissues).Theresults showed that C/EBP was diffusely distributed in nuclei and cytoplasm of differentiated liv-er cells and very low or undetectable in liver cancer cells.The expression of C/EBP was in pro-portion to differentiated degree of tumor cells,and was obviously weaker than that in surround-ing nontumorous tissues.C/EBP positive staining has also been found in regenerating epithelialcells of bile ductules.The results suggested that C/EBP might play an important role in estab-lishing and maintaining the differentiation of liver cells and might exert an inhibiting effect againsttransformation of liver cells and proliferation of neoplastic tissue.  相似文献   
68.
Objective To establish the measurement of IgA1 O-glycan-specific antiglycan autoantibodies in patients with IgA nephropathy (IgAN), and evaluate their role in the development and progression of IgAN. Methods In the IgAN regular follow-up cohort of Peking University Institute of Nephrology from January 2006 to December 2015, 170 patients drawn by stratified randomization were enrolled in this study. Enzyme-linked immunosorbent assay (ELISA) was used to determine the levels of plasma galactose-deficient IgA1 (Gd-IgA1) and antiglycan autoantibody (IgG and IgA1). The correlation between antiglycan autoantibodies and clinicopathological parameters was analyzed by linear correlation and multiple linear regression analysis. The receiver operating characteristic curve (ROC) was used to evaluate the value of plasma anti glycide antibodies in the diagnosis of IgAN. Results IgG and IgA1 antiglycan autoantibodies that specifically recognized Fab-hinge region (Fab-HR) antigens could be detected in both IgAN and healthy control group. Agglutinin inhibition test showed that the specific antigen epitope was N-acetylgalactosamine (GalNAc) residue exposed to galactose deficiency in IgA1 hinged region. There was no significant difference in the absolute levels of plasma IgG antiglycan autoantibodies between IgAN and healthy controls (P=0.963). After adjustment of the plasma level of IgG, the normalized antiglycan autoantibody (ln[IgG antiglycan antibody/IgG]) in patients with IgAN was significantly higher than that in healthy controls (0.58±0.31 vs 0.37±0.11, P﹤0.01). The normalized level of IgG antiglycan autoantibody in IgAN patients was positively correlated with 24 h urine protein level during renal biopsy (Spearman r=0.183, P﹤0.05), and was also significantly correlated with 24 h urinary protein level after adjusting for baseline clinical and pathological factors (β=0.713, 95%CI 0.323-1.102, P﹤0.01). The area under ROC curve (AUC) of normalized IgG antiglycan autoantibody in the diagnosis of IgAN was 0.764 (95% CI 0.682-0.845, P﹤0.05). Using the cut-off value of 0.396, the sensitivity and specificity of normalized IgG antiglycan autoantibody for IgAN were 0.729 and 0.700 respectively. There was no significant difference in the absolute or normalized levels of IgA1 antiglycan autoantibodies between IgAN patients and healthy controls. Conclusions Gd-IgA1-specific antiglycan autoantibodies can be detected both in IgAN patients and healthy controls. They are elevated in some patients with IgAN and possibly involved in the development of IgAN.  相似文献   
69.
Zhou J  Meng R  Sui X  Meng L  Jia J  Yang B 《Haematologica》2005,90(9):1277-1279
We studied the effects of varying and steady-state concentrations of arsenic trioxide (As2O3) on apoptosis and differentiation of several cell lines in vitro. We also studied the same effects of fluctuating vs constant concentrations of As2O3 in vivo in patients treated with daily 3-hour fast infusions or daily slow, continuous infusions. Intracellular concentrations of arsenic and apoptosis rate were higher whereas differentiation was reduced in cells exposed to constant concentrations of As2O3.  相似文献   
70.
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