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161.
Gye Won Kim Sung Youl Hong Soon Cheon Shin Sung Hee Lee Won Bae Kim 《Archives of pharmacal research》1987,10(1):18-24
Mouse monoclonal antibodies to Hepatitis B surface antigen(HBsAg) were prepared and their functional capabilities tested by the method of solid phase enzyme linked immuno sorbent assay(ELISA). HBsAg binding studies indicated that one monoclonal antibody 6E-1-1 bound more HBsAg at a faster rate than the other monoclonal antibodies. Also, for the binding inhibition studies with the selected monoclonal antibody 6E-1-1, one monoclonal antibody 8D-3-6 didn’t exhibit binding inhibition for HBsAg. Then, a simultaneous ELISA method was developed for the immunodiagnosis of HBsAg. Different combinations of two monoclonal antibodies as solid phase and horseradish peroxidase(HRPO) labeled phase were studied. The combination of monoclonal antibody of higher affinity constant (6E-1-1) immobilized in a solid phase and monoclonal antibody of lower affinity constant (8D-3-6) as a HRPO labeled phase was more sensitive when two monoclonal antibodies of different affinity constants for HBsAg were prepared. 相似文献
162.
A new tetrahydrofuran lignan, named henricine ( 1), was isolated from the stems of SCHISANDRA HENRYI. High resolution COSY spectrum was used in the structural elucidation. 相似文献
163.
溃疡性结肠炎(UC)是一种临床常见的消化系统疾病,致病机制尚不明确,病情复杂多变,迁延难愈,治疗周期漫长,且无特效药。目前,UC的治疗多采用皮质类固醇、氨基水杨酸及生物制剂等西医手段,短时间起效快,疗效确切。但随着用药时间的延长,部分患者会出现耐药性和加剧病情发展,导致结肠癌的发生。有研究发现,氧化应激是UC重要的致病因素之一,影响着UC的发生、发展。氧化应激是机体内氧化产物与抗氧化系统不平衡的一种应激状态,丙二醛(MDA)、活性氧(ROS)、一氧化氮(NO)等氧化产物的过表达或者超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽(GSH)抗氧化酶的不足都会导致氧化应激的发生。值得注意的是,中医药作为我国独有的医学特色,运用中医药治疗UC疾病已经取得显著的成效。研究表明,中医药一方面通过抑制代谢产物的堆积,有效抑制UC发生,另一方面,通过提高抗氧化系统,达到拮抗UC发展的治疗效果。因此,以中医药调节氧化平衡状态作为诊疗思路,可能是未来治疗UC疾病的新手段、新方向。基于上述研究,该文总结了氧化应激关键致病蛋白与UC发生、发展的作用机制,归纳了中药有效成分、单味中药、中药复方、针灸调控氧化应激上下游靶点蛋白,减轻肠黏膜病理损害,降低结肠损伤指数,以及丰富肠道菌群,增加结肠长度,改善UC临床症状,以期为扩大中医药治疗UC疾病的应用范围,提供可靠的科学理论依据。 相似文献
164.
Priyanka Sharma Guojun Wu Deeptha Kumaraswamy Natalie Burchat Hong Ye Yongjia Gong Liping Zhao Yan Y. Lam Harini Sampath 《Nutrients》2021,13(2)
7,8-Dihydroxyflavone (DHF) is a naturally occurring flavonoid that has been reported to protect against a variety of pathologies. Chronic administration of DHF prevents high-fat diet (HFD)-induced obesity in female, but not male, mice. However, the mechanisms underlying this sexual dimorphism have not been elucidated. We have discovered that oral DHF supplementation significantly attenuates fat mass, hepatic lipid accumulation, and adipose tissue inflammation in female mice. In contrast, male mice were not protected from adiposity, and had a paradoxical worsening of hepatic lipid accumulation and adipose tissue inflammation upon DHF supplementation. Consistent with these sexually dimorphic effects on body weight and metabolic health, 7,8-DHF induced early and stable remodeling of the female intestinal microbiome. DHF supplementation significantly increased gut microbial diversity, and suppressed potentially detrimental bacteria, particularly Desulfovibrionaceae, which are pro-inflammatory and positively associated with obesity and inflammation. Changes in the female gut microbiome preceded alterations in body weights, and in silico analyses indicated that these early microbial changes were highly predictive of subsequent weight gain in female mice. While some alterations in the intestinal microbiome were also observed in male DHF-supplemented mice, these changes were distinct from those in females and, importantly, were not predictive of subsequent body weight changes in male animals. The temporality of microbial changes preceding alterations in body weight in female mice suggests a role for the gut microbiome in mediating the sexually dimorphic effects of DHF on body weight. Given the significant clinical interest in this flavonoid across a wide range of pathologies, further elucidation of these sexually dimorphic effects will aid the development of effective clinical therapies. 相似文献
165.
Xin-Ran Liu Na Zhu Yun-Tao Hao Xiao-Chen Yu Zhen Li Rui-Xue Mao Rui Liu Jia-Wei Kang Jia-Ni Hu Yong Li 《Nutrients》2021,13(3)
Radiation therapy is widely used in the treatment of tumor diseases, but it can also cause serious damage to the body, so it is necessary to find effective nutritional supplements. The main purpose of this study is to evaluate the protective effect of whey hydrolysate peptides (WHPs) against 60Coγ radiation damage in mice and explore the mechanism. BALB/c mice were given WHPs by oral gavage administration for 14 days. Then, some mice underwent a 30-day survival test after 8 Gy radiation, and other mice received 3.5 Gy radiation to analyze the changes in body weight, hematology and bone marrow DNA after three and 14 days. In addition, through further analysis of the level of oxidative stress and intestinal barrier function, the possible mechanism of the radioprotective effect of WHPs was explored. The study found WHPs can prolong survival time, restore body weight, and increase the number of peripheral blood white blood cells and bone marrow DNA content in irradiated mice. In addition, WHPs can significantly improve the antioxidant capacity, inhibit pro-inflammatory cytokines and protect the intestinal barrier. These results indicate that WHPs have a certain radioprotective effect in mice, and the main mechanism is related to reducing oxidative damage. 相似文献
166.
Basnet Sulochana Frongillo Edward A. Nguyen Phuong Hong Moore Spencer Arabi Mandana 《Maternal and child health journal》2021,25(6):946-946
Maternal and Child Health Journal - The article “Factor Structure and Equivalence of Maternal Resources for Care in Bangladesh, Vietnam, and Ethiopia”, written by Sulochana Basnet,... 相似文献
167.
巨细胞病毒DNA早期抗原与巨细胞病毒-IgM、IgG滴度一致率的对比研究 总被引:3,自引:0,他引:3
目的 :正确认识巨细胞病毒 (CMV)DNA及CMV早期抗原 (EA)的病毒学意义及临床价值。方法 :检查 34例急性黄疸性肝炎患儿和 19例健康儿童的血白细胞CMV DNA、尿CMV DNA、血白细胞CMV EA ,并与其同时检测的CMV IgM、CMV IgG双份血清 (急性期 /恢复期 )滴度有 4倍以上升高 (IgG升高 )相比较。结果 :CMV DNA与CMV IgM及CMV IgG升高的一致率都低于 5 0 % ;CMV EA与CMV IgM的一致率为 6 6 .7% (肝炎患儿 )、6 8.4% (健康儿童 ) ,显著高于血CMV DNA( 37.7% ,P <0 .0 1)和 CMV DNA( 4 4.4% ,P <0 .0 5 )与CMV IgM的一致率 ,但CMV EA与CMV IgG升高无相关性 ;CMV DNA与CMV EA在肝炎患儿和健康儿童中的检出率无显著差异性。结论 :CMV DNA定性检查不适于做为CMV活动性感染的指标 ,而CMV EA更能反映CMV的活动性感染。联合开展CMV的多种抗原检查以及定量检查CMV 抗原和DNA可能是必要的 相似文献
168.
169.
目的 了解肾综合症出血热(HFRS)各期血清蛋白的变化特点及其与肝、肾功能的关系。方法 采用瑞士产COBAS MIRA PLUS CC全血动生化分析仪及日本产MA-4210尿液分析仪分别检测同时的空腹静脉血及晨尿。结果 150例HFRS患者217次检测血清总蛋白(T)平均为63.51g/L,白蛋白(A)为36.29g/L,球蛋白(G)为27.22g/L,A/G=1.33。其中A/G为1.49-1.0者137例(63.3%),A/G<1.0者27例(12.44%),A/G≥1.5者53例(24.42%)。结论 HFRS患者有75.58%存在着低白蛋白血症,并贯穿于各期,异常程度与病情轻重呈正相关,主要原因是肾脏损害,大量白蛋白从尿中丢失,与肝脏的合成功能关系不大。 相似文献
170.
Bio—Normalizer(BN)对体外鼠胚大脑神经细胞缺氧损伤保护作用的研究 总被引:1,自引:0,他引:1
目的:为研究Bio-Normalizer(BN)对大脑神经细胞缺氧损伤的保护作用,并探讨其机制。方法:本研究采用无血清体外细胞培养方法,培养鼠胚大脑神经细胞,将神经细胞造成缺氧损伤,在无血清培养液中加入不同剂量的BN,观察BN对缺氧损伤的保护作用。将细胞分为4组,Ⅰ组为缺氧BN浓度为0mg/ml组;Ⅱ组为缺氧BN浓度为0.1mg/ml组,Ⅲ组为缺氧BN浓度为0.5mg/ml组;Ⅳ组为非缺氧BN浓度为0mg/ml组。在倒置显微镜下观察细胞生长发育的情况,于细胞培养后的第4天收集细胞,测定生化指标,同时进时光镜和电镜病理检查。结果:缺氧0.1mgBN/ml组的神经细胞MTT及NSE活性均高于缺氧0mgBN/ml组,并有显著差别(P<0.05);形态学观察结果也显示缺氧0.1mgBN/ml组和0.5mgBN/ml组的神经细胞缺氧损伤后恢复明显好于缺氧0mgBN/ml组。结论:BN对大脑神经细胞缺氧损伤恢复具有明显的促进作用。 相似文献