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991.
本文报告用2BS细胞分离戊型肝炎病毒(HEV)感染成功的猴肝脏标本中的HEV的初步结果,将2BS细胞长成致密单层,接种已知含有HEV的肝悬液,盲传至第4代,发现在第27天细胞出现了轻微的细胞病变(CPE),随着进一步的传代,细胞病变时间逐渐提前。至第7代时,在第17天就可见到CPE,CPE的主要特征是细胞间隙变宽,透明度降低和轻度细胞破坏,无大片细胞溶解和脱落现象。免疫电镜检查在第5代和第6代细胞培养液中见到很少的27—34nm的病毒颗粒。将第4代至第7代的细胞悬液20ml接种了3只恒河猴,有2只猴在24天和26天出现了典型的ALT升高,待这3只猴恢复正常后一年,再次接种以上细胞悬液20ml,3只猴全部发生了ALT升高,并在胆汁中检查到27—34nm的病毒颗粒,我们初步推测2BS适应的这株病毒很可能是戊型肝炎病毒。  相似文献   
992.
To search for more microbial resources for screening environment-friendly antifoulants, we investigated the phylogenetic diversity and antifouling potentials of culturable fungi in mangrove sediments from Techeng Isle, China. A total of 176 isolates belonging to 57 fungal taxa were recovered and identified. The high levels of diversity and abundance of mangrove fungi from Techeng Isle were in accordance with previous studies on fungi from other mangrove ecosystems. Fifteen of the 176 isolates demonstrated high divergence (87–93%) from the known fungal taxa in GenBank. Moreover, 26 isolates recorded in mangrove ecosystems for the first time. These results suggested that mangrove sediments from Techeng Isle harbored some new fungal communities compared with other mangrove ecosystems. The antifouling activity of 57 representative isolates (belonging to 57 different fungal taxa) was tested against three marine bacteria (Loktanella hongkongensis, Micrococcus luteus and Pseudoalteromonas piscida) and two marine macrofoulers (bryozoan Bugula neritina and barnacle Balanus amphitrite). Approximately 40% of the tested isolates displayed distinct antifouling activity. Furthermore, 17 fungal isolates were found to display strong or a wide spectrum of antifouling activity in this study, suggesting that these isolates deserve further study as potential sources of novel antifouling metabolites. To our knowledge, this is the first report on the investigation of the phylogenetic diversity and antifouling potential of culturable fungi in mangrove sediments from Techeng Isle, China. These results contribute to our knowledge of mangrove fungi and further increases the pool of fungi available for natural bioactive product screening.  相似文献   
993.
Microfluidic arrays of living cells have raised a lot of interests recently due to their potential for high throughput screening of cell-based assays. This report presents a microfluidic cell array with individually addressable chambers controlled by pneumatic valves for cell culture and treatment. There are two modes for the cell array to be operated. In the first mode, different groups of cells are directed into designated chambers for culturing and observation. We demonstrate the delivery and culture of enhanced green fluorescent protein (EGFP) expressing and nonfluorescent Chinese hamster ovary (CHO) cells into specific chambers in the array. In the second mode, the chambers are first seeded with the same cell type and different reagents are delivered to specific chambers for cell treatment. We treat cells in designated chambers with Calcein AM and CellTrace calcein red-orange AM to demonstrate the principle. We envision that this microfluidic cell array technology will pave the way to automated high-throughput screening of biomolecules and drugs based on observing cellular phenotypes and responses.  相似文献   
994.
We developed an RNA-silencing vector, pSilent-Dual1 (pSD1), with a convergent dual promoter system that provides a high-throughput platform for functional genomics research in filamentous fungi. In the pSD1 system, the target gene was designed to be transcribed as a chimeric RNA with enhanced green fluorescent protein (eGFP) RNA. This enabled us to efficiently screen the resulting transformants using GFP fluorescence as an indicator of gene silencing. A model study with the eGFP gene showed that pSD1-based vectors induced gene silencing via the RNAi pathway with slightly lower efficiency than did hairpin eGFP RNA-expressing vectors. To demonstrate the applicability of the pSD1 system for elucidating gene function in the rice-blast fungus Magnaporthe oryzae , 37 calcium signalling-related genes that include almost all known calcium-signalling proteins in the genome were targeted for gene silencing by the vector. Phenotypic analyses of the silenced transformants showed that at least 26, 35 and 15 of the 37 genes examined were involved in hyphal growth, sporulation and pathogenicity, respectively, in M. oryzae. These included several novel findings such as that Pmc1 -, Spf1 - and Neo1 -like Ca2+ pumps, calreticulin and calpactin heavy chain were essential for fungal pathogenicity.  相似文献   
995.
将构建好的可表达GST融合蛋白的重组病毒AcMNPV-OCC^--GST-6xHis-Etp28感染Sf9细胞,一定时间后取感染了病毒的细胞裂解物上清液进行SDS-PAGE分析,结果显示53kDa的融合蛋白(GST-6xHis-Etp28)呈不溶状态。在原有裂解液的基础上,加固体十二烷基肌氨酸钠致终浓度1.5%,并将Triton X-100的比例由1%提高到2%。SDS-PAGE结果显示至少有1/  相似文献   
996.
BIIB021 is a novel, orally available inhibitor of heat shock protein 90 (Hsp90) that is currently in phase I/II clinical trials. BIIB021 induces the apoptosis of various types of tumor cells in vitro and in vivo. The aim of this study is to investigate the effect of BIIB021 on the radiosensitivity of esophageal squamous cell carcinoma (ESCC). The results indicated that BIIB021 exhibited strong antitumor activity in ESCC cell lines, either as a single agent or in combination with radiation. BIIB021 significantly downregulated radioresistant proteins including EGFR, Akt, Raf-1 of ESCC cell lines, increased apoptotic cells and enhanced G2 arrest that is more radiosensitive cell cycle phase. These results suggest that this synthetic Hsp90 inhibitor simultaneously affects multiple pathways involved in tumor development and progression in the ESCC setting and may represent a better strategy for the treatment of ESCC patients, either as a monotherapy or a radiosensitizer.  相似文献   
997.
对国人颅骨径的测量已不少见,但多为依据骨骼人类学性别特征进行性别鉴定、或未经性别鉴定的材料,而对已知生前性别者的测量并不甚多,为了积累国人体质材料,并为人类学、解剖学及法医学等研究提供参考依据,我们按《人体骨骼测量方法》(吴汝康等,1965)和《人体测量手册》(邵象清,1985)等所列标准为主要依据,对青岛出土、已知性别(据墓碑记载)、多为汉族、较完整的312例(男154,女158)成人颅骨进行了十四项径的直线测量,对所测数据进行了统计学处理和性别差异检验。现将主要结果列于上页表。  相似文献   
998.
稀土元素对生物机体剂量效应机理的研究   总被引:3,自引:0,他引:3  
综述了稀土元素对生物机体剂量效应的机理,从稀土对细胞质膜、细胞周期及细胞凋亡、CaM水平调节的作用到对蛋白质、DNA的影响等不同层次和水平进行了探讨,以期为稀土在生物学领域的进一步广泛应用奠定理论基础.  相似文献   
999.
双歧杆菌及其WPG对S180荷瘤小鼠免疫调节和抑瘤的作用研究   总被引:12,自引:3,他引:12  
目的 通过观察双歧杆菌及其细胞壁肽多糖(Cell Wall Preparation,whole peptidoglycon,WPG)对S180荷瘤小鼠抑瘤作用及在体内外对IL-6和TNF-α生态的影响,探讨双歧杆菌及其WOG的免疫调节和抑瘤作用机制。方法 采用经驯化而具有一定耐氧能力的两歧双歧杆菌C149株及其WPG腹腔免疫S180荷瘤小鼠,应用放射免疫检测小鼠外周血中的IL-6和TNF-α的含量,同时在体外观察小鼠腹腔巨噬细胞产生IL-6和TNF-α的影响。结果 双歧杆菌及其WPG在体内外对IL-6和TNF-α的生成有明显的促进作用,对S180荷瘤小鼠均有明显抑瘤作用。结论 双歧杆菌及其WPG可能通过刺激小鼠的巨噬细胞产生一些免疫活性因子而间接发挥抑瘤作用。  相似文献   
1000.
为了克隆被孢霉不饱和脂肪酸生物合成途径的相关酶基因,构建了基于λgt10的被孢霉cDNA文库。cDNA文库库容量为2×10.6pfu。以已克隆的被孢霉△9脂肪酸脱饱和酶保守区cDNA为探针对被孢霉cDNA文库进行筛选。经过两轮筛选获得1个阳性克隆,其插入片段长度大于16kb。  相似文献   
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