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31.
转 Bt基因抗虫棉对棉大卷叶螟抗性的研究   总被引:7,自引:0,他引:7  
:转Bt基因抗虫棉对棉铃虫有很好的抗性,对棉大卷叶螟(SyleptaderogataFabricius)的抗性未见报道。作者研究表明,棉大卷叶螟在棉田为聚集分布型,低龄幼虫有集中为害习性;抗虫棉对其有很好的抗性,平均虫株率为2.2%,较常规棉中棉所12降低96.6%;百株虫量为133.8头,较常规棉降低88.4%。  相似文献   
32.
AIM: To investigate the differentiation from adult rat and human bone marrow mesenchymal stem cells (BMMSCs) into neuron with musk polypeptide (Mu-P).METHODS: Adult rat and human BMMSCs were induced with Mu-P.Neuron-specific enolase (NSE),neurofilament (NF),Nestin,glial fibrillary acidic protein (GFAP) were detected by immunohistochemistry.RESULTS: Simple methods with Mu-P induced adult rat and human BMMSCs exhibiting a neuronal phenotype,expressing Nestin at 3 hours to 5 hours,and expressing NE and NF at 5 hours to 7 days.But the neuron-like cells didn't express the glial astrocyte marker GFAP.CONCLUSION: Adult rat and human BMMSCs can be induced to differentiate into neurons with Mu-P.  相似文献   
33.
淡紫拟青霉几丁质酶对南方根结线虫的影响   总被引:11,自引:0,他引:11  
研究表明淡紫拟青霉产生的几丁质酶能显著增加南方根结线虫卵的孵化率。线虫卵用酶液浸泡后,其孵化率与酶的纯度呈正相关。经DEAE-22和SephcrylS-300两步纯化的几丁质酶处理卵2天和4天,分别使卵的孵化率增加222.3%和242.6%。淡紫拟青霉几丁质酶对南方根结线虫幼虫有一定的致死作用,纯化后酶液浸泡2天,卵中孵出的幼虫存活率下降53.5%。  相似文献   
34.
金顶侧耳与黄白侧耳性亲和特性的研究   总被引:4,自引:1,他引:4  
研究了金顶侧耳 (Pleurotuscitrinipileatus)与黄白侧耳 (Pleurotuscornucopiae)的性亲和性及其杂交菌株的特性 ,结果表明 :金顶侧耳与黄白侧耳相互亲和 ;获得的 2株杂交菌株CC - 1、CC - 2的生长最适宜温度分别为 2 3 38~ 2 4 6 2℃、 2 3 6 1~ 2 4 19℃ ,而其亲本金顶侧耳 (0 5 79)和黄白侧耳 (MH0 0 30 1)交配型基准株的最适宜生长温度分别为 2 4 0 3~2 6 37℃、 2 4 2 7~ 2 6 33℃ ,杂交菌株的最适宜生长温度均低于亲本菌株  相似文献   
35.
基于GIS的祁连山森林景观格局分析   总被引:24,自引:2,他引:24  
在地理信息系统软件ArcGIS环境下 ,将祁连山区DEM图和坡向图分别同植被图叠加 ,分析研究区各景观组分在空间的分布特征 ;用定量分析景观结构和景观格局程序Fragstats计算景观和各景观组分的相关指数 ,分析其连通性、完整性、破碎化程度及聚集程度。结果表明 :研究区各景观组分分布受海拔高度和坡向的影响非常明显。各景观组分的完整性、连通性和破碎化程度也很不均衡。草地是研究区面积最大、连通性和完整性最好的景观组分 ;青海云杉林呈斑块状或带状分布在阴坡和半阴坡 ,形状最为不规则 ,平均斑块面积小且距离近 ,易受干扰而发生重大变化 ;宜林地和祁连圆柏林相对于农田、疏林地有较强的扩张特征 ;而杨类阔叶林各斑块间相隔距离大 ,斑块之间的邻接性差 ,破碎化程度最为严重。  相似文献   
36.
AIM: To study effects of urokinase-type plasminogen activator (uPA) signal transduction on expression of matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of matrix metalloproteinase-3 (TIMP-3) in giant cell tumor of bone (GCT). METHODS: Expression of uPAR, MMP-2 and TIMP-3 in GCT tissue was detected by immunohistochemistry. Phosphorylation level of mitogen-activated protein kinase (p44) in uPA/uPAR signal pathway in cultured GCT cells was detected by immunoprecipitation. The expression of MMP-2 and TIMP-3 in cultured cells after treatment with uPA-ATF or anti-uPAR antibody was also detected by Western blotting. RESULTS: 1) Urokinase-type plasminogen activator receptor (uPAR) was positive on the cell membrane and in cytoplasm of some mononuclear stromal cells (MSCs) and multinucleated giant cells (MGCs); 2) MMP-2 was positive in the cytoplasm and on the cell membrane of almost all of MSCs and some of MGCs. The polar distribution of MMP-2 in the cytoplasm of MGCs was especially obvious; 3) The expression of TIMP-3 of some MSCs and MGCs in GCT was much lower than MMP-2. The positive signal also showed a prominent polarity; 4) After treatment with uPA-ATF, the phosphorylation level of p44 in GCT cultured cells was much higher than the control. Addition of anti-uPAR antibody in the cells remarkably down-regulated the phosphorylation level of p44 as compared with the control group, suggesting that uPA-ATF participates cell signal transduction and this reaction can be inhibited by anti-uPAR antibody; 5) uPA-ATF cell signal pathway up-regulated expression of MMP-2 and TIMP-3, while anti-uPAR antibody down-regulated the expression of MMP-2 and TIMP-3. CONCLUSION: These results demonstrate for the first time that uPA-ATF directly regulates the expression of MMP-2 and TIMP-3 by signal transduction pathway, and the over-expression of MMP-2 and TIMP-3 may play an important role in local osteolysis of GCT.  相似文献   
37.
AIM: To investigate the relationship between p21WAF1gene polymorphisms and protein expression in breast carcinoma. METHODS: Polymerase chain reaction single-strand conformation polymorphisms technique (PCR-SSCP) and immunohistochemical assay of S-P immunostaining technique were used to study polymorphisms of p21WAF1 and protein expression respectively on the specimen of paraffin-embedded tissues in 100 cases of breast carcinomas and 40 benign breast diseases as control. RESULTS: Two p21WAF1 gene polymorphisms were found in 18% (18/100) of breast carcinomas and 5% (2/40) of control samples. The difference between the two groups was statistically significant (χ2=3.94, P<0.05). The positive immunohistochemical reaction of p21WAF1 protein were found in 50% (50/100) of breast carcinomas and 12.5% (5/40) of control samples. The difference between the two groups was statistically significant (χ2=16.84, P<0.01). The positive immunohistochemical reaction of p21WAF1 protein were found in 100% (18/18) of breast carcinomas with p21WAF1 gene polymorphisms and 39% (32/82) of no p21WAF1 gene polymorphisms. The difference between two groups was statistically significant (χ2=21.95, P<0.01). The p21WAF1 gene polymorphisms were correlated with the protein expression in breast carcinomas (r=0.576, P<0.01). CONCLUSION: p21WAF1 gene polymorphisms may create the different copies of mRNA and may make relevant protein molecules.  相似文献   
38.
AIM: The goal of this study was to compare different methods for tumor antigen preparation, to observe the induction of tumor-specific cytotoxic T lymphocytes in rats by dendritic cells (DCs) pulsed with different tumor antigens. METHODS: The precursors of dendritic cells were isolated from bone marrow of rats, stimulated in vitro with recombinent rat granulocyte-macrophage colony-stimulating factor (rrGM-CSF) and interleukin-4 (rrIL-4). Then rat DCs were pulsed with C6 tumor cell antigens prepared with different methods: freeze-thaw, boiling or total protein extracted from ultrasonic crushed tumor cell. Subsequently primed DCs were cocultured with T lymphocytes isolated from spleen to induce CTL. Lymphocyte chemoattractant factor from DCs and cytokine IFN-γ release were determined by ELISA, the cytotoxicity of CTL was assayed by JAM test. RESULTS: DCs pulsed with boiled tumor cell in vitro induced an enhanced ability of T-cell proliferation and cytotoxic T lymphocyte activity.CONCLUSION: Our results demonstrated that DCs primed with boiled tumor cell may represent a method for inducing immune responses against the entire repertoire of tumor antigens of malignancies.  相似文献   
39.
禽流感病毒夹心ELISA快速检测方法的研究   总被引:21,自引:1,他引:21  
以禽流感病毒(AIV)湖北分离株(H9N2亚型)提纯物为免疫原,制备出鸡抗AIV和兔抗AIV抗体,经用琼脂扩散法测得效价分别为1:32和1:16。以纯化的鸡抗AIVIgG为包被抗体,兔抗AIVIgG为第二抗体,建立了检测AIV抗原的夹心ELISA法。结果表明,鸡抗AIVIgG的最佳包被浓度为1μg/mL,兔抗AIV IgG的最适工作浓度为5μg/mL;对已知的阳性样品,用夹心ELISA法测得的病毒滴度比血球凝集滴度高16倍以上,且能检出其它亚型的禽流感病毒;与新城疫病毒、传染性支气管炎病毒、减蛋综合征病毒、传染性喉气管炎病毒、传染性法氏囊病病毒、鸡痘病毒、马立克氏病病毒等无交叉反应,说明本方法有很高的特异性及敏感性。对14个鸡场送检的、患有呼吸道疾病或有腹膜炎、眼炎、产蛋下降、怀疑为禽流感感染的病鸡进行了检测,结果有7个鸡场为阳性。本方法的建立为禽流感病鸡群的临床检验提供了一种方便、敏感、快速的检测方法。  相似文献   
40.
采用Ficoll密度梯度离心,提取第 19期(孵化 72h)性腺中的PGCs,对其应用不同的冷冻保护液和不同的平衡方法进行冷冻保存,并于复苏后进行体外培养。复苏后的PGCS用台盼蓝染色检测其存活率,结果发现:从第 19期性腺中获取的PGCs在同一种冷冻保护液下,采用不同的平衡方法进行冷冻,对PGCs的存活率有显著影响(P<0.05)或极显著影响(P<0.01);平衡方法相同,在不同冷冻保护液之间存在显著(P<0.05)或极显著 (P<0.01)差异。PGCs经体外培养 24h后再进行冷冻保存,复苏后其存活率、体外培养存活时间均极显著(P<0.01)短于分离后直接冷冻的PGCs。  相似文献   
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