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961.
962.
本研究利用生物信息学分析了日本血吸虫(Schistosoma japonicum,sj)Glycogen synthase kinase 3(GSK3)蛋白,并对其中一个GSK3蛋白的编码cDNA进行了克隆和原核表达,制备了特异性的多克隆抗体.同时,还初步评估了重组蛋白的免疫保护效果.生物信息学分析表明在日本血吸虫数据库存在两种GSK3蛋白,且其中一个SjGSK3在日本血吸虫不同发育时期均有转录.Western blot结果表明本研究制备的抗体能特异性识别日本血吸虫SjGSK3重组蛋白,表明该重组蛋白具有良好的免疫原性.动物实验表明免疫SjGSK3重组蛋白的动物与佐剂对照组比较分别获得了平均10.6%减虫率和40.5%肝脏减卵率. 相似文献
963.
鹅副粘病毒感染鸡试验 总被引:7,自引:0,他引:7
本室分离的鹅副粘病毒是一侏对鹅具有料强致病毒,它也能实验感染雏鸡,且雏鸡感染后发病率均为100%,死亡率50%以上。人工感染的鸡其症状和病理变化均与鹅自然发病的病变相类似。从感染途径看,注射接触(混养)均能感染发病,并且在感染发病及死亡时间上也与鹅感染情况相似,因此该病毒感染鹅同时又能实验感染雏鸡,而且传播之迅速,危害之严重必须引起养禽户的重视。 相似文献
964.
965.
AIM: To evaluate how ST14/MT-SP1 overexpression alters invasiveness of colorectal cancer cells.METHODS: Human full length ST14/MT-SP1 gene was transiently transfected into colorectal cancer (RKO) cell lines.The expression products were purified by chromatography on Ni2+-affinity resin column and analyzed for gelatinase activity by gelatin zymography.Cell invasion and migration were determined by ECM invasion assay in vitro.RNA was isolated from stable ST14-transfected RKO cells and a cDNA microarray was utilized to detect the change in expression of MMPs and TIMPs.Real-time quantitative PCR was used to validate the change of expression.RESULTS: The full length ST14/MT-SP1 was transfected and expressed in RKO cells.The expressed protein showed a gelatinase activity.In addition,invasiveness of RKO was significantly enhanced by ST14/MT-SP1 overexpression (P<0.01).Blockage of ST14/MT-SP1 resulted in a decrease in the invasiveness of SW480 and SW620 (P<0.01).Furthermore,MT2-MMP (MMP-15) expression was significantly up-regulated (2.5-fold change) and TIMP2 down-regulated (0.35-fold change) by ST14/MT-SP1 overexpression in RKO.CONCLUSION: ST14/MT-SP1 overexpression results in an increase in invasiveness of colorectal cancer RKO cells.Increased invasiveness is due to an increase in the gelatinase activity of ST14/MT-SP1 and a change in up-regulated MT2-MMP and down-regulated TIMP-2 expression.Therefore,ST14/MT-SP1 overexpression enhances invasiveness of colorectal cancer cells. 相似文献
966.
ZHOU Hui-ru 《农业科学与技术》2008,9(2)
The main morphological characteristics, producing area and growth characteristics of sixteen new varieties of Chinese white poplar (Populus to-mentoso Carr. ) are reported, aiming at providing referernce for breeding and extension of new varieties. 相似文献
967.
968.
The method "Material Flow Analysis (MFA)" is one of the effective tools to study law and quantification of material flow between economic system and ecological system. On the national level, economy-wide material flow analysis has been published for a number of countries. However, published studies on the regional or local level are still very limited and a standardized method does not exist yet. On the basis of framework of Material Flow Analysis proposed by Eurostat, the paper collected related data and analyzed material input and output for the Chengyang district in Qingdao. The results showed that DMI (Direct Material Input) and TMR (Total Material Requirement) in absolute number increased about 3.6 and 3.9 times, respectively from 1995 to 2004. Fossil fuel and mineral contributed to about 50.3%-76.3% of DMI. Imports of material increased about 5.0 times and became the most important Contributor to DMI, which showed that local economic growth was highly dependent on resources from other regions and countries. DPO (Domestic Processed Output) and TDO (Total Domestic Output) represent slow increasing trend, and DPO contributed to 22.2%-58.1% of TDO, suggesting local hidden flows were of obvious effect on TDO. The biggest component of DPO is CO2, approximately accounting for 90% of DPO. The material productivity increased 57.7% in last decade, reflecting improvement of efficiency of resources utilization in some extent. However, compared to developed countries and regions, material productivity of Chengyang district was relatively low. Therefore, in order to promote the sustainability, it is essential to develop circular economy and enhance materials productivity. 相似文献
969.
WANG Hong-yan WU Xiao-yan ZHANG Xu-yan XING Yong-mei ZHOU Ya-bin JIA Ji-hui TIAN Yong-jie 《园艺学报》2008,24(8):1510-1513
AIM: To observe the immune property of cervical carcinoma and antitumour effect of heat-killed lactobacilli adhered to HeLa cells. METHODS: Flow cytometry was used to analyze the expression of immune molecules on HeLa cells after adhered with heat-killed lactobacilli. MTT was used to analyze the cytotoxity of lymphocytes on cervical carcinoma cells. RESULTS: Adherence of heat-killed lactobacilli to HeLa cells did not affect the expression of MHC-I molecules (P>0.05), but enhanced the expression of CD80, CD86 significantly (P<0.05) in HeLa cells. Adherence of heat-killed lactobacilli to HeLa cells also enhanced the cytotoxity of NK cells. Compared to control, the cytotoxity of CTL to HeLa carcinoma cells was significantly enhanced by the adherence of heat-killed lactobacilli to HeLa cells (P<0.05). CONCLUSION: Heat-killed lactobacilli strengthen the antitumor effect on HeLa cells. 相似文献
970.