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YANG Shi-bin XIAO Long-bin XU Feng-feng WU Wen-hui LI Shou-zhi LI Ming-zhe 《园艺学报》2012,28(7):1224-1229
AIM: To evaluate the relationship between epithelial cell adhesion molecule (EPCAM)/cluster of differentiation 44 (CD44)/cluster of differentiation 24 (CD24) expression and the clinicopathological characteristics/prognosis in 95 gastric cancer patients. METHODS: The expression levels of EPCAM, CD44 and CD24 were detected using the two-step method of immunohistochemistry in 95 gastric cancer patients who underwent surgical excision and were pathologically diagnosed as gastric cancer. RESULTS: There were 56 EPCAM-positive patients (58.95%), 41 CD44-positive patients (43.16%) and 56 CD24-positive patients (58.95%). Thirty patients were both EPCAM and CD44 positive (31.58%), 45 patients were both EPCAM and CD24 positive (47.37%), 32 patients were both CD44 and CD24 positive (33.68%), and 25 patients were EPCAM, CD44 and CD24 positive (26.32%). EPCAM expression was correlated with age, depth of tumor infiltration and WHO histological classification. CD44 expression was correlated with BORRMANN and WHO histological classification as well as CEA value. CD24 expression was correlated with the depth of infiltration, location of the tumor, WHO histological classification and viscera invasion. All positive expression of EPCAM, CD44 and CD24 was correlated with the depth of infiltration, location of the tumor and WHO histological classification (P<0.05). The difference of survival rate between EPCAM positive group and negative group was observed, and the CD44 positive group and negative group had the same result (P<0.05 and P<0.01, respectively). The difference of survival rate between EPCAM+CD44+CD24+ group and EPCAM-CD44-CD24- group was statistically significant (P<0.05). The difference of survival rate between EPCAM-CD44+CD24+ group and EPCAM-CD44-CD24- group was also significant (P<0.05). CONCLUSION: The positive rates of EPCAM, CD44 and CD24 expression are high in gastric cancer tissues and these 3 proteins can be used as primary screening targets. 相似文献
174.
大草蛉在我国分布广泛,能捕食多种农作物害虫。本试验首先研究了大草蛉一龄幼虫对桃蚜、大草蛉二龄幼虫对桃蚜和夹竹桃蚜的捕食功能反应。三个反应的最大捕食量Namax分别为144.93、303.03和151.51(头),瞬时攻击率a分别为0.7428、0.8654和0.6644。大草蛉一龄幼虫有较强的种内干扰反应,随着捕食者密度的增加,捕食作用率(E)依次为0.2025、0.1185、0.0866、0.0694和0.0584;对桃蚜的捕食作用率(E)与自身密度(P)的函数关系式为E=0.2025P-0.7727。在桃蚜和夹竹桃蚜的混合种群中,大草蛉二龄幼虫对桃蚜的选择效应大于夹竹桃蚜。 相似文献
175.
二化螟是我国水稻的重要钻蛀性害虫,常年发生危害严重,给水稻生产带来巨大产量损失。寄生蜂是二化螟重要的生态调节因子和生物防控天敌资源,对田间二化螟的种群数量具有明显的自然控制作用。本文主要就二化螟寄生蜂多样性及其影响因素、二化螟卵寄生蜂和幼虫寄生蜂生态控害功能及优势种利用、二化螟幼虫越冬滞育期间寄生蜂对越冬幼虫种群基数的控制和寄生蜂生态控害功能的评估等方面的研究与应用进行综述,并探讨寄生蜂对二化螟生态控害功能的评估,尝试提出二化螟寄生蜂生态控害功能研究应在越冬代重视二化螟盘绒茧蜂、稻螟小腹茧蜂和中华钝唇姬蜂对越冬滞育幼虫的生态控害潜力、非越冬世代则重点发掘稻螟赤眼蜂、螟黄赤眼蜂和玉米螟赤眼蜂等卵期优势寄生蜂以降低田间二化螟卵的孵化率、减轻二化螟幼虫为害率,以期为提升寄生蜂的生态控害功能提供参考。 相似文献
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为制备非肌肉肌球蛋白Ⅱ型重链A(NMHC-II A)的单克隆抗体(MAb),本研究将编码NMHC-Ⅱ A羧基端1 651~1 960氨基酸的表达重组质粒转化到大肠杆菌感受态细胞Rosseta中诱导表达,重组蛋白纯化后免疫BALB/c小鼠,分离小鼠脾细胞与SP2/0骨髓瘤细胞用PEG 4000介导融合。ELISA方法检测筛选阳性杂交瘤细胞,制备腹水并纯化MAb,以间接免疫荧光和免疫沉淀方法鉴定MAb的特异性,western blot检测MAb靶位点区域。结果表明,通过筛选得到1株稳定分泌抗体的杂交瘤细胞系,其抗体亚型为IgG1,细胞培养上清和腹水效价分别为1∶2 560和1∶1.0×106;该MAb能够特异性结合相应抗原,并结合Marc-145细胞;western blot结果显示该抗体与NMHC-Ⅱ A的1 812~1 894氨基酸位点结合。该抗体的制备为研究NMHC-Ⅱ A在猪繁殖与呼吸综合征病毒感染细胞中的作用奠定了基础。 相似文献
178.
GU Qing-fang YU Jie-zhong GUO Min-fang WEI Wen-yue XIAO Bao-guo ZHANG Guang-xian MA Cun-gen 《园艺学报》2019,35(12):2227-2234
AIM: To explore the neuroprotective effect of novel Rho kinase inhibitor FSD-C10 on Alzheimer disease (AD) model of APP/PS1 double transgenic (Tg) mice. METHODS: Male APP/PS1 Tg mice (n=20) at 8 months of age were randomly divided into 2 groups:model group and FSD-C10 treatment group. The mice were treated with normal saline or FSD-C10 (25 mg·kg-1·d-1) by intraperitoneal injection, once daily for 2 months. Age-and sex-matched wild-type (WT) mice without treatment were used as the control. The Morris water maze (MWM) test and SMART 3.0 behavioral record system were applied to examine and analyze the spatial cognitive function of the mice. The protein levels and distribution of Aβ, p-tau and synapse-associated proteins such as synaptophysin, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) and postsynaptic density protein 95 (PSD-95) were determined by immunofluorescence staining. The protein levels of phosphorylated amyloid precursor protein at Thr668[p-APP(Thr668)], beta-site APP-cleaving enzyme 1 (BACE1) and synapse-associated proteins in the brain were analyzed by Western blot. RESULTS: Compared with model group, FSD-C10 treatment significantly improved the cognitive function of the APP/PS1 Tg mice, accompanied by reduced Aβ deposition and p-tau level, increased protein level of p-APP (Thr668) in the central nervous system, decreased expression of BACE1, and increased expression of synapse-associated proteins in the brain of the mice (P<0.05). CONCLUSION: FSD-C10 has neuroprotective potential in the APP/PS1 Tg mice. The mechanism may be related to enhancing the non-amyloidogenic APP cleavage pathway, reducing the production of Aβ oligomers, the deposition of senile plaques and the amount of tau protein, up-regulating synapse-associated proteins, and increasing synaptic plasticity. 相似文献
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随着我国养殖业的迅猛发展,各种疾病的发生和危害日益加重,特别是病毒性疫病,已成为传染病的主体。对于病毒性疾病的治疗仍然缺乏有效的药物,且大多数尚无效果可靠的疫苗,再加上新发和再发病不断出现,使得病毒病危害尤为突出,急待寻找提高机体免疫、抵抗病毒感染的替代药物。干扰素(IFN)作为一种细胞因子具有广谱抗病毒、抗肿瘤和免疫调节活性,还可以促进机体免疫反应,提高机体抗病毒感染能力,使病毒在机体存活和复制的几率降到最低。目前发现Ⅰ型、Ⅱ型和Ⅲ型3种类型的IFN,利用3种类型的IFN的抗病毒和调节免疫的功能,研究抑制病毒复制的新型生物制剂,成为人们关注和研究的热点,为病毒性疫病,特别是新发或突发的重大疫病防控提供参考。 相似文献