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31.
Ohmefentanyl stereoisomers induce changes of CREB phosphorylation in hippocampus of mice in conditioned place preference paradigm 总被引:4,自引:0,他引:4
The present study was designed to determine the changes of phosphorylation of cAMP-response element binding protein(CREB)in hippocampus induced by ohmefentanyl stereoisomers(F9202 and F9204) in conditioned place preference(CPP)paradigm.The results showed that mice receiving F9202 and F9204 displayed obvious CPP.They could all significantly stimulate CREB phosphorylation and maintained for a long time without affecting total CREB protein levels.The effect of F9204 was similar to morphine which effect was more potent and longer than F9202.We also examined the effects of ketamine,a noncompetitive N-mthyl-D-asartate receptor(NR)antagonist,on morphine-,F9202-and F9204-induced CPP and phosphorylation of CREB in hippocampus.Ketamine could suppress not only the place preference but also the phosphorylation of CREB produced by morphine,F9202 and F9204.These findings suggest that alterations in the phosphorylation of CREB be relevant to opiates signaling and the development of opiates dependence.NR antagonists may interfere with opiates dependence and may have potential therapeutic implications. 相似文献
32.
Dengue infection is a major cause of morbidity in tropical and subtropical regions, bringing nearly 40% of the world population at risk and causing more than 20,000 deaths per year. But there is neither a vaccine for dengue disease nor antivirai drugs to treat the infection. In recent years, dengue infection has been particularly prevalent in India, Southeast Asia, Brazil, and Guangdong Province, China. In this article, we present a brief summary of the biological characteristics of dengue virus and associated flaviviruses, and outline the prowess on studies of vaccines and drugs based on potential targets of the dengue virus. 相似文献
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不同植物生长调节剂对中华猕猴桃扦插生根的影响 总被引:4,自引:0,他引:4
以中华猕猴桃"桂海4号"为试材,采用500mg·L-1、1000mg·L-1、1500mg·L-1三种不同浓度的吲哚丁酸、萘乙酸、和ABT生根粉处理插条,进行了猕猴桃扦插试验。结果表明:吲哚丁酸1500mg·L-1的扦插生根率极显著高于萘乙酸和ABT生根粉的各个处理,显著高于吲哚丁酸1000mg·L-1;吲哚丁酸对根数和根长的促进作用优于萘乙酸和ABT生根粉,ABT生根粉对于根粗的促进作用却较其它两者强;主成分分析结果表明,吲哚丁酸1500mg·L-1处理的插条生长情况最好。 相似文献
36.
miR-124-1 is a tumour suppressor microRNA (miR). Epigenetic deregulation of miRs is implicated in carcinogenesis. Promoter DNA methylation and histone modification of miR-124-1 was studied in 5 normal marrow controls, 4 lymphoma, 8 multiple myeloma (MM) cell lines, 230 diagnostic primary samples of acute myeloid leukaemia (AML), acute lymphoblastic leukaemia (ALL), chronic myeloid leukaemia (CML), chronic lymphocytic leukaemia (CLL), MM, and non-Hodgkin's lymphoma (NHL), and 53 MM samples at stable disease or relapse. Promoter of miR-124-1 was unmethylated in normal controls but homozygously methylated in 4 of 4 lymphoma and 4 of 8 myeloma cell lines. Treatment of 5-Aza-2'-deoxycytidine led to miR-124-1 demethylation and re-expression of mature miR-124, which also associated with emergence of euchromatic trimethyl H3K4 and consequent downregulation of CDK6 in myeloma cells harboring homozygous miR-124-1 methylation. In primary samples at diagnosis, miR-124-1 methylation was absent in CML but detected in 2% each of MM at diagnosis and relapse/progression, 5% ALL, 15% AML, 14% CLL and 58.1% of NHL (p<0.001). Amongst lymphoid malignancies, miR-124-1 was preferentially methylated in NHL than MM, CLL or ALL. In primary lymphoma samples, miR-124-1 was preferentially hypermethylated in B- or NK/T-cell lymphomas and associated with reduced miR-124 expression. In conclusion, miR-124-1 was hypermethylated in a tumour-specific manner, with a heterochromatic histone configuration. Hypomethylation led to partial restoration of euchromatic histone code and miR re-expression. Infrequent miR-124-1 methylation detected in diagnostic and relapse MM samples showed an unimportant role in MM pathogenesis, despite frequent methylation found in cell lines. Amongst haematological cancers, miR-124-1 was more frequently hypermethylated in NHL, and hence warrants further study. 相似文献
37.
Genome-wide association study identified genetic variations and candidate genes for plant architecture component traits in Chinese upland cotton 总被引:1,自引:0,他引:1
Junji Su Libei Li Chi Zhang Caixiang Wang Lijiao Gu Hantao Wang Hengling Wei Qibao Liu Long Huang Shuxun Yu 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2018,131(6):1299-1314
Key message
Thirty significant associations between 22 SNPs and five plant architecture component traits in Chinese upland cotton were identified via GWAS. Four peak SNP loci located on chromosome D03 were simultaneously associated with more plant architecture component traits. A candidate gene, Gh_D03G0922, might be responsible for plant height in upland cotton.Abstract
A compact plant architecture is increasingly required for mechanized harvesting processes in China. Therefore, cotton plant architecture is an important trait, and its components, such as plant height, fruit branch length and fruit branch angle, affect the suitability of a cultivar for mechanized harvesting. To determine the genetic basis of cotton plant architecture, a genome-wide association study (GWAS) was performed using a panel composed of 355 accessions and 93,250 single nucleotide polymorphisms (SNPs) identified using the specific-locus amplified fragment sequencing method. Thirty significant associations between 22 SNPs and five plant architecture component traits were identified via GWAS. Most importantly, four peak SNP loci located on chromosome D03 were simultaneously associated with more plant architecture component traits, and these SNPs were harbored in one linkage disequilibrium block. Furthermore, 21 candidate genes for plant architecture were predicted in a 0.95-Mb region including the four peak SNPs. One of these genes (Gh_D03G0922) was near the significant SNP D03_31584163 (8.40 kb), and its Arabidopsis homologs contain MADS-box domains that might be involved in plant growth and development. qRT-PCR showed that the expression of Gh_D03G0922 was upregulated in the apical buds and young leaves of the short and compact cotton varieties, and virus-induced gene silencing (VIGS) proved that the silenced plants exhibited increased PH. These results indicate that Gh_D03G0922 is likely the candidate gene for PH in cotton. The genetic variations and candidate genes identified in this study lay a foundation for cultivating moderately short and compact varieties in future Chinese cotton-breeding programs.38.
39.
Roegneria grandis was hybridized withR. ciliaris var.japonensis (2n = 28, SSYY),Elymus caninus (2n = 28, SSHH), andPseudoroegneria spicata (2n = 28, SSSS). Chromosome pairing was studied in parents and hybrids. It is concluded from this study that: (i)R. grandis is an allotetraploid species and contains the basic genomes S and Y: (ii) a certain degree of homoeology exists between the S and Y genomes of the species studied. 相似文献
40.
CO1在侧耳属物种快速鉴定中的应用 总被引:1,自引:0,他引:1
以侧耳属Pleurotus15个种的15个菌株为材料,根据GenBank上侧耳属细胞色素c氧化酶亚基Ⅰ基因(cytochrome c oxidase subunit 1 gene,CO1)序列信息,设计引物CO332F、CO332R,进行第一轮PCR扩增,结果显示所有菌株都能得到单一条带,根据条带大小,15个菌株可分为4组。随后针对每个种设计特异性引物,进行第二轮PCR扩增,结果显示每个菌株只有在自己特异的引物中出现目的条带。通过两轮扩增,根据扩增条带的大小和有无,即可对15个种进行快速鉴定。 相似文献