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41.
宁夏甜菜丛根病的研究   总被引:1,自引:0,他引:1  
发生在宁夏甜菜上的一种病毒病的病株叶丛主要表现为黄化、焦桔和叶脉黄化坏死。从其分离的病毒粒子呈杆状,宽约20nm,长度为65—110nm、270—300nm和390—420nm,能侵染甜菜、菠菜、昆诺阿藜、苋色藜、番杏,与甜菜坏死黄脉病毒(BNYVV)抗血清呈阳性反应。综上所述,认为该病害是由BNYVV引起的。  相似文献   
42.
Almost all infectious diseases are initiated at mucosal surfaces, yet intramuscular or subcutaneous vaccination usually provides only minimal protection at sites of infection owing to suboptimal activation of the mucosal immune system. The neonatal Fc receptor (FcRn) mediates the transport of IgG across polarized epithelial cells lining mucosal surfaces. We mimicked this process by fusing a model antigen, herpes simplex virus type-2 (HSV-2) glycoprotein gD, to an IgG Fc fragment. Intranasal immunization, together with the adjuvant CpG, completely protected wild-type, but not FcRn knockout, mice after intravaginal challenge with virulent HSV-2 186. This immunization strategy induced efficient mucosal and systemic antibody, B- and T-cell immune responses, with stable protection for at least 6 months after vaccination in most of the immunized animals. The FcRn-IgG transcellular transport pathway may provide a general delivery route for subunit vaccines against many mucosal pathogens.  相似文献   
43.
初产母猪断奶后能否正常发情对养猪生产影响重大,也是初产母猪被淘汰的主要原因。本研究以乏情和发情初产母猪为研究对象,首次利用RNA-seq技术对其下丘脑-垂体-卵巢轴中的基因间长链非编码RNAs(long intergenic noncoding RNAs,lincRNAs)进行筛选比较,得到lincRNAs的表达图谱,并对其特征和功能进行了初步分析。结果显示,在乏情和发情初产母猪下丘脑–垂体–卵巢轴中鉴定得到3519个lincRNAs,以发情组为对照共有17个lincRNAs存在差异表达,其中12个表达上调,5个表达下调(FC≥2,P<0.05)。选择4个差异表达的lincRNAs经qRT-PCR验证,其表达水平与测序结果基本一致。对这17个差异表达的lincRNAs进行GO分析、KEGG通路分析及lincRNA-mRNA共表达网络分析,发现这些lincRNAs主要与猪卵母细胞减数分裂成熟、卵巢细胞分化及颗粒细胞凋亡等生殖活动相关。本研究结果丰富了猪lincRNAs数据资源,为进一步深入研究初产母猪的生殖机能提供了理论依据。  相似文献   
44.
用菠菜甜菜碱醛脱氢酶 ( BADH)免疫巴比西 ( BALB/c)小鼠 ,将其脾细胞与骨髓瘤细胞 SP2 /O-Ag1 4融合 ,在 1 92孔中 ,有约 1 4 %孔生长的杂交瘤细胞 ,用间接酶联免疫方法 ( ELISA)检测表现为阳性。选择其中 2 G3和 2 D10 细胞系 ,用有限稀释法进行克隆化培养 ,约 2 0 %克隆化细胞为强阳性。选择其中 2 G3- H3细胞株注射到 BALB/c小鼠腹腔中诱导腹水 ,腹水的单抗效价为 1∶ 1 0 3。应用 BADH单抗检查了大麦、水稻、高粱、小麦幼苗的叶片和根的粗提物 ,均呈阳性反应 ,表明 BADH除在光合组织中存在外 ,在非光合组织中也可能存在。讨论了非光合组织 BADH的意义  相似文献   
45.
Sorghum, a C4 model plant, has been studied to develop an understanding of the molecular mechanism of resistance to stress. The auxin-response genes, auxin/indole-3-acetic acid (Aux/IAA), auxin-response factor (ARF), Gretchen Hagen3 (GH3), small auxin-up RNAs, and lateral organ boundaries (LBD), are involved in growth/development and stress/defense responses in Arabidopsis and rice, but they have not been studied in sorghum. In the present paper, the chromosome distribution, gene duplication, promoters, intron/exon, and phylogenic relationships of Aux/IAA, ARF, GH3, and LBD genes in sorghum are presented. Furthermore, real-time PCR analysis demonstrated these genes are differently expressed in leaf/root of sorghum and indicated the expression profile of these gene families under IAA, brassinosteroid (BR), salt, and drought treatments. The SbGH3 and SbLBD genes, expressed in low level under natural condition, were highly induced by salt and drought stress consistent with their products being involved in both abiotic stresses. Three genes, SbIAA1, SbGH3-13, and SbLBD32, were highly induced under all the four treatments, IAA, BR, salt, and drought. The analysis provided new evidence for role of auxin in stress response, implied there are cross talk between auxin, BR and abiotic stress signaling pathways.  相似文献   
46.
我们从1983年9月至1985年1月,将草鱼尾鳍组织细胞在体外培养17个月,传代100次,确立为建立的细胞系(established cell lioe),命名为GCCF-2。    相似文献   
47.
Potato virus Y (PVY) is an important pathogen of potato (Solanum tuberosum). Although the PBS1–RPS5 immune system is well documented in Arabidopsis thaliana, it has not been reported in potato. In Arabidopsis, the bacterial effector AvrPphB cleaves AtPBS1 to trigger an immune response. Here, we show that the AvrPphB-triggered immune response is mediated by StPBS1, a close homologue of AtPBS1 in potato. However, downstream signalling of StPBS1 was mediated by unknown resistance (R) proteins other than potato orthologues of AtRPS5 and HvPBR1, which is important for HvPBS1 signalling in barley. Immune signalling of StPBS1 is mediated by the AvrPphB C-terminal cleavage domain and an STKPQ motif, in contrast to AtPBS1-mediated immunity in which both AvrPphB cleavage fragments and an SEMPH motif are essential. The cleavage sequence of AvrPphB in StPBS1 was replaced with that of the PVY NIa-Pro protease to obtain StPBS1NIa. StPBS1NIa overexpression potato displayed stronger immunity to PVY infection than did the StPBS1 transgenic lines. StPBS1NIa was cleaved at the expected target site by NIa-Pro protease from PVY. Thus, we characterized the function of StPBS1 in potato immunity and provide a biotechnology control method for PVY via transformation of decoy-engineered StPBS1NIa.  相似文献   
48.
Lung cancer is the leading cause of cancer death in both men and women. Tumor metastasis is an essential aspect of lung cancer progression. nm23-H1 is a metastasis suppressor gene. The molecular mechanism by which nm23-H1 suppresses the metastasis is still unclear. Here, we compared the gene expression profile of human large cell lung cancer cell line NL9980 by nm23-H1 gene silencing with that of negative control cells to comprehensively investigate nm23-H1-mediated changes in gene expression of NL9980 cells. Microarray assay revealed that expression of 733-known genes (1.9%, 733/38,500) were altered in response to nm23-H1 gene silencing, including 466 upregulated genes and 267 downregulated. real-time PCR assay of the expression changes indicated that 81.82% (45/55) of verified genes were consistent with that observed in microarray assay. The upregulated genes included MMP-1, -2, SNAI2, CXCL1, 2, 3, PAI-2, while the downregulated genes included cystatin B, TIMP-2, E-cadherin, centrin-2, all of which have been associated with tumor metastasis. Furthermore, we confirmed by Western blot that the expression of MMP-1 and -2 were significantly increased while that of cystatin B was dramatically decreased in NL9980-nm23-H1 silencing cells. The NL9980-nm23-H1 silencing cells exhibited significantly more S phase growth and invasive ability. Thus, silencing of nm23-H1 gene caused metastasis-related gene expression changes in lung cancer cells. The knockdown of nm23-H1 expression may change the lung cancer cells to a more invasive phenotype through alteration in the expression of a set of genes.  相似文献   
49.
Summary Polyurethane foam cubes were employed as carriers to immobilize Rhizopus oryzae for L(+)-lactic acid production. The immobilizing capacity reached 450 g-fresh cell/l-cube. The production rate of L(+)-lactic acid could be threefold increased by using the immobilized R. oryzae. The immobilized cells could be steadily used in repetitive fermentations for more than 10 batches.  相似文献   
50.
Apelin signaling to the family of mitogen-activated protein kinases (MAPKs), such as extracellular-regulated kinases 1/2 (ERK1/2) and p38 MAPK, through the coupling of apelin receptor (APJ) to G-protein, mediates important pathophysiological responses. Although apelin fragments have been reported to induce ERK1/2 activation through Gi-protein, the intracellular pathways by which APJ activates these MAPKs are only partially understood. Here, using stably transfected human embryonic kidney 293 (HEK293) cells overexpressing human APJ (HEK293-apelinR), we showed that apelin-13 signaling leads to ERK1/2 and p38 MAPK pathways through APJ activation. It was found in HEK293-apelinR cells that ERK1/2 activation was initiated by apelin-13 at 5 min, with the peak of activation occurring at 15 min, and a return to the basal level within 60 min. The activation of ERK1/2 appeared to be dose-dependent with a significant activation being observed at 10 nM apelin-13 and maximal activation at 100 nM. However, phosphorylated-p38 MAPK was not detected in HEK293-apelinR cells treated with apelin-13. We also shown that the apelin-13-induced ERK1/2 activation requires a coupling with pertussis toxin-sensitive G-protein, and that overexpression of dominant-negative Gi2 completely inhibits the apelin-13-induced ERK1/2 activation. In addition, treatment with apelin-13 resulted in a concentration-dependent reduction of forskolin-stimulated cAMP production. It is therefore suggested that apelin-13 activates ERK1/2 but not p38 MAPK, which involves the coupling of APJ to the Gi2 cascade. In conclusion, the ERK1/ 2, but not p38 MAPKpathway is activated by apelin-13 through coupling of human APJ to Gi2-protein, which contributes to cellular responses.  相似文献   
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