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121.
SMV感染供试品种种子传毒率最高为29.60%,最低1.04%。SMV弱毒株系的传毒率高于其强毒株系。大豆品种营养生长的V_4时期以前感染SMV种子传毒率最高,花期感染种传率显著下降。供试品种中,有初花期感病种子即不传毒;有盛花期感病仍有很低的种传率;亦有结荚初期感病还有很低种传率的品种。SMV流行的收获种子传毒率高低主要取决于大豆营养生长和花期田间病株率的高低。根据品种间早期感染SMV的最高种传率不同、花期感染种传率显著下降的特性,建立了SMV田间流行的种子传毒率预测模型。 相似文献
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Chronic Helicobacter pylori Infection Does Not Significantly Alter the Microbiota of the Murine Stomach 总被引:1,自引:0,他引:1 下载免费PDF全文
Mai Ping Tan Maria Kaparakis Maja Galic John Pedersen Martin Pearse Odilia L. C. Wijburg Peter H. Janssen Richard A. Strugnell 《Applied microbiology》2007,73(3):1010-1013
We examined the impact of Helicobacter pylori infection on the murine gastric microbiota by culture and terminal-restriction fragment length polymorphism and found that neither acute nor chronic H. pylori infection substantially affected the gastric microbial composition. Interestingly, the total H. pylori burden detected by real-time PCR was significantly higher than that revealed by viable counts, suggesting that the antigenic load sustaining H. pylori-induced gastritis could be considerably higher than previously believed. 相似文献
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Bing Xu Shaolin Wang Yan Jiang Linlin Yang Ping Li Caixia Xie 《Animal biotechnology》2013,24(4):217-225
Grass carp, Ctenopharyngodon idellus (Valenciennes, 1844), is an economically important species widely cultured in the world, but its genome research resources are largely lacking. The objectives of this study were to construct normalized cDNA libraries for efficient EST analysis, to generate ESTs from these libraries, and to identify EST-related molecular markers such as microsatellites and single nucleotide polymorphisms (SNPs) for genetic analysis of this species. A total of 6,269 ESTs were generated representing 4,815 unique sequences, from which 105 putative microsatellites and 5,228 SNPs were identified. These genome resources provide the material basis for future genetic and functional analyses in this species. 相似文献
126.
Xiaolian Gu Ping Zhuang Feng Zhao Xiaotao Shi Xiaorong Huang Guangpeng Feng Tao Zhang Jianyi Liu Longzhen Zhang Boyd Kynard 《Environmental Biology of Fishes》2017,100(1):27-33
Experiments were conducted in artificial stream tanks with juvenile Chinese sturgeon, Acipenser sinensis, captured in the Yangtze Estuary to test two null hypotheses (1) juveniles have no preference for white or black substrates, and (2) white or black substrate color has no effect on juvenile feeding efficiency on the barcheek goby,Rhinogobius giurinus, a dark-colored prey of wild juveniles. Juveniles strongly preferred white substrate. However, in feeding tests, feeding efficiency by juveniles was similar on white or black substrates. Thus, substrate color had no effect on feeding efficiency. Results suggest the innate preference for white substrate is not a visual adaptation for capturing prey on a contrasting background, but is an adaptation predisposing juveniles to seek light-colored sandy substrate where forage abundance is greatest. 相似文献
127.
Min Lu Bin Liu Hui Xiong Fang Wu Chunhong Hu Ping Liu 《Journal of cellular and molecular medicine》2019,23(4):2431-2441
Despite initial dramatic efficacy of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (EGFR‐TKIs) in EGFR‐mutant lung cancer patients, subsequent emergence of acquired resistance is almost inevitable. Resveratrol and its derivatives have been found to exert some effects on EGFR‐TKI resistance in non‐small cell lung cancer (NSCLC), but the underlying mechanisms remain unclear. We screened several NSCLC cell lines with gefitinib resistance by MTT assay and analysed the miR‐345/miR‐498 expression levels. NSCLC cells were pre‐treated with a resveratrol derivative, trans‐3,5,4‐trimethoxystilbene (TMS) and subsequently challenged with gefitinib treatment. The changes in apoptosis and miR‐345/miR‐498 expression were analysed by flow cytometry and q‐PCR respectively. The functions of miR‐345/miR‐498 were verified by CCK‐8 assay, cell cycle analysis, dual‐luciferase reporter gene assay and immunoblotting analysis. Our results showed that the expression of miR‐345 and miR‐498 significantly decreased in gefitinib resistant NSCLC cells. TMS pre‐treatment significantly upregulated the expression of miR‐345 and miR‐498 increasing the sensitivity of NSCLC cells to gefitinib and inducing apoptosis. MiR‐345 and miR‐498 were verified to inhibit proliferation by cell cycle arrest and regulate the MAPK/c‐Fos and AKT/Bcl‐2 signalling pathways by directly targeting MAPK1 and PIK3R1 respectively. The combination of TMS and gefitinib promoted apoptosis also by miR‐345 and miR‐498 targeting the MAPK/c‐Fos and AKT/Bcl‐2 signalling pathways. Our study demonstrated that TMS reduced gefitinib resistance in NSCLCs via suppression of the MAPK/Akt/Bcl‐2 pathway by upregulation of miR‐345/498. These findings would lay the theoretical basis for the future study of TMS for the treatment of EGFR‐TKI resistance in NSCLCs. 相似文献
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129.
Phosphorylation on tyrosine-15 of p34(Cdc2) by ErbB2 inhibits p34(Cdc2) activation and is involved in resistance to taxol-induced apoptosis 总被引:4,自引:0,他引:4
Tan M Jing T Lan KH Neal CL Li P Lee S Fang D Nagata Y Liu J Arlinghaus R Hung MC Yu D 《Molecular cell》2002,9(5):993-1004
ErbB2 overexpression confers resistance to taxol-induced apoptosis by inhibiting p34(Cdc2) activation. One mechanism is via ErbB2-mediated upregulation of p21(Cip1), which inhibits Cdc2. Here, we report that the inhibitory phosphorylation on Cdc2 tyrosine (Y)15 (Cdc2-Y15-p) is elevated in ErbB2-overexpressing breast cancer cells and primary tumors. ErbB2 binds to and colocalizes with cyclin B-Cdc2 complexes and phosphorylates Cdc2-Y15. The ErbB2 kinase domain is sufficient to directly phosphorylate Cdc2-Y15. Increased Cdc2-Y15-p in ErbB2-overexpressing cells corresponds with delayed M phase entry. Expressing a nonphosphorylatable mutant of Cdc2 renders cells more sensitive to taxol-induced apoptosis. Thus, ErbB2 membrane RTK can confer resistance to taxol-induced apoptosis by directly phosphorylating Cdc2. 相似文献
130.
SPOP Promotes Nanog Destruction to Suppress Stem Cell Traits and Prostate Cancer Progression 总被引:1,自引:0,他引:1