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281.
小麦抗蚜品种(系)或材料的抗性遗传测定及筛选   总被引:16,自引:1,他引:15  
测定了部分小麦品种(系)或材料的丁布(DIMBOA)含量及几个和抗蚜性有关的物理性状(叶、叶毛长度和密度,蜡质含量),同时对这些品种(系)或材料进行抗麦长管蚜(Macrosiophum avenae(F.))鉴定,统计其累计蚜量。结果表明,丁布含量及各物理性状与累计蚜量均成负相关关系,通过多目标综合决策分析,认为1粒小麦(Triticum monococcum)和材料98-10-9是比较好的抗性种质资源,生产上广泛推广的千斤早是感蚜的品种。  相似文献   
282.
The development of different generations of BCR-ABL1 tyrosine kinase inhibitors (TKIs) has led to the high overall survival of chronic myeloid leukemia (CML) patients. However, there are CML patients who show resistance to TKI therapy and are prone to progress to more advanced phases of the disease. So, implementing an alternative approach for targeting TKIs insensitive cells would be of the essence. Dihydroorotate dehydrogenase (DHODH) is an enzyme in the de novo pyrimidine biosynthesis pathway that is located in the inner membrane of mitochondria. Here, we found that CML cells are vulnerable to DHODH inhibition mediated by Meds433, a new and potent DHODH inhibitor recently developed by our group. Meds433 significantly activates the apoptotic pathway and leads to the reduction of amino acids and induction of huge metabolic stress in CML CD34+ cells. Altogether, our study shows that DHODH inhibition is a promising approach for targeting CML stem/progenitor cells and may help more patients discontinue the therapy.Subject terms: Cancer metabolism, Apoptosis  相似文献   
283.
D Xu  B Zhang  G Liang  J Ping  H Kou  X Li  J Xiong  D Hu  L Chen  J Magdalou  H Wang 《PloS one》2012,7(9):e44497
Epidemiological investigations have shown that fetuses with intrauterine growth retardation (IUGR) are susceptible to adult metabolic syndrome. Clinical investigations and experiments have demonstrated that caffeine is a definite inducer of IUGR, as children who ingest caffeine-containing food or drinks are highly susceptible to adult obesity and hypertension. Our goals for this study were to investigate the effect of prenatal caffeine ingestion on the functional development of the fetal hippocampus and the hypothalamic-pituitary-adrenal (HPA) axis and to clarify an intrauterine HPA axis-associated neuroendocrine alteration induced by caffeine. Pregnant Wistar rats were intragastrically administered 20, 60, and 180 mg/kg·d caffeine from gestational days 11-20. The results show that prenatal caffeine ingestion significantly decreased the expression of fetal hypothalamus corticotrophin-releasing hormone. The fetal adrenal cortex changed into slight and the expression of fetal adrenal steroid acute regulatory protein (StAR) and cholesterol side-chain cleavage enzyme (P450scc), as well as the level of fetal adrenal endogenous corticosterone (CORT), were all significantly decreased after caffeine treatment. Moreover, caffeine ingestion significantly increased the levels of maternal and fetal blood CORT and decreased the expression of placental 11β-hydroxysteroid dehydrogenase-2 (11β-HSD-2). Additionally, both in vivo and in vitro studies show that caffeine can downregulate the expression of fetal hippocampal 11β-HSD-2, promote the expression of 11β-hydroxysteroid dehydrogenase 1 and glucocorticoid receptor (GR), and enhance DNA methylation within the hippocampal 11β-HSD-2 promoter. These results suggest that prenatal caffeine ingestion inhibits the development of the fetal HPA axis, which may be associated with the fetal overexposure to maternal glucocorticoid and activated glucocorticoid metabolism in the fetal hippocampus. These results will be beneficial in elucidating the developmental toxicity of caffeine and in exploring the fetal origin of adult HPA axis dysfunction and metabolic syndrome susceptibility for offspring with IUGR induced by caffeine.  相似文献   
284.
羊草无性系植物种群觅养生长格局与资源分配的研究   总被引:34,自引:3,他引:34       下载免费PDF全文
本文按照理论种群生态学的研究方法,从生长参数的形态功能变化和发育参数的时间变化入手,系统地研究了羊草无性系植物种群觅养生长格局与资源分配的基本规律。研究结果表明,羊草无性系种群适合于用ψ=0.5、μ=1.0、Tr=7和Ts=2的分配函数模型描述其觅养生长格局与资源分配。文中建立了大小—制约分配模型,并用此模型预测了与觅养生长格局有关的资源分配。这一研究深刻地揭示了较为动物种群搜索途径复杂得多的无性系植物种群的觅养行为。  相似文献   
285.
红莲型水稻细胞质雄性不育花粉总蛋白质初步比较分析   总被引:4,自引:0,他引:4  
采用固相pH梯度/SDS-PAGE双向电泳对红莲型细胞质雄性不育水稻的不育系(YTA)和保持系(YTB)二核期花粉总蛋白质进行了分离,通过银染显色,获得了分辨率和重复性较好的双向电泳图谱。用PDQuest2DE软件可识别约1500个蛋白质点,其中差异表达的蛋白质点数为120。将其中15个差异点采用基质辅助激光解析电离飞行时间质谱(matrix assisted laser desorption/ionizaton time of flight mass spectrometry,MALDI-TOF-MS)进行了肽质指纹图分析,通过采用Mascot软件对MSDB数据库查询,其中7个蛋白质点得到了鉴定。YTA相对于YTB有部分参与物质和能量代谢的蛋白质缺失或表达量降低,这些蛋白质分别是水稻线粒体H -转运ATPase(H -ATPase)α链、盐诱导型膜联蛋白、线粒体NAD -依赖型苹果酶和磷酸核糖焦磷酸合成酶等。这些蛋白质的表达下调或缺失可能与线粒体提供能量不足而导致的花粉不能正常发育有关。线粒体电压依赖性阴离子通道(VDAC)这一重要蛋白质在YTA中的上调表达有可能与花粉败育过程中细胞的程序性死亡相关。  相似文献   
286.
在室内人工光源照射条件下, 探究150 μmol∙m-2·s-1光强下不同比例的红蓝光对拟南芥(Arabidopsis thaliana)生长发育的影响。以哥伦比亚(Columbia-0)野生型拟南芥为研究对象, 采用荧光粉激发型LED作为植物生长光源, 以SrSiAlN3为红色基底, 调节荧光粉添加量获得不同红蓝光谱, 考察不同光照条件下拟南芥萌发率、根长、株高、叶绿素含量和相对电导率等参数的变化规律。结果表明, 在荧光粉激发型LED光照调节下的拟南芥具有更高的萌发率、根长、株高、叶绿素含量和相对电导率, 且在红蓝光质比为2:1时萌发率(95.63%)和叶绿素含量(26.7)最高; 在红蓝光质比为4:5时根长(4.19 cm)较长; 在红蓝光质比为4:1时株高(15.5 cm)较高; 在红蓝光质比为4:5时相对电导率(40.5 S·m-1)较大。研究结果表明相对平衡的光质(红蓝光质比为4:1)有利于拟南芥生长发育, 且减少蓝光比例对根系生长及叶绿素积累有一定的促进作用。研究表明不同光谱对模式植物拟南芥的生长发育有较明显的影响, 改变光谱组成可以对植物的生长发育起不同程度的调控作用。  相似文献   
287.
Acute myeloid leukaemia (AML) is a highly heterogeneous haematologic malignancy with poor prognosis. We previously showed synergistic antileukaemic interaction between exportin 1 (XPO1) inhibitor KPT‐330 (Selinexor) and Bcl‐2 inhibitor venetoclax (ABT‐199) in preclinical models of AML, which was partially meditated by Mcl‐1, although the full mechanism of action remains unknown. In this study, using real‐time RT‐PCR and Western blot analysis, we show that inhibition of XPO1 via KPT‐330 or KPT‐8602 (Eltanexor) decreases the mRNA and protein levels of c‐Myc, CHK1, WEE1, RAD51 and RRM2. KPT‐330 and KPT‐8602 induce DNA damage, as determined by alkaline comet assay. In addition, we demonstrate that venetoclax enhances KPT‐330‐ and KPT‐8602‐induced DNA damage, likely through inhibition of DNA damage repair. This study provides new insight into the molecular mechanism underlying the synergistic antileukaemic activity between venetoclax and XPO1 inhibitors against AML. Our data support the clinical evaluation of this promising combination therapy for the treatment of AML.  相似文献   
288.
Zhang  Hao  Jiang  Changhua  Wang  Rui  Zhang  Long  Gai  Ruonan  Peng  Siyuan  Zhang  Yi  Mao  Chanjuan  Lou  Yuxia  Mo  Jianbin  Feng  Shucheng  Ming  Feng 《Plant molecular biology》2021,106(6):569-587
Plant Molecular Biology - Our results provide insights into heat response mechanisms among Clematis species. Overexpressing CvHSFA2 enhanced the heat resistance of yeast and silencing NbHSFA2...  相似文献   
289.
290.
Pancreatic ductal adenocarcinoma (PDA) responds poorly to treatment. Efforts have been exerted to prolong the survival time of PDA, but the 5-year survival rates remain disappointing. Understanding the molecular mechanisms of PDA development is significant. MEK/ERK pathway signaling has been proven to be important in PDA. lncRNA–mRNA networks have become a vital part of molecular mechanisms in the MEK/ERK pathway. Herein, weighted gene coexpression network analysis was used to investigate the coexpressed lncRNA–mRNA networks in the MEK/ERK pathway based on GSE45765. Differently expressed long noncoding RNA (lncRNA) and messenger RNA (mRNA) were found and 10 modules were identified based on coexpression profiles. Gene ontology and Kyoto Encyclopedia of Genes and Genomes were then performed to analyze the coexpressed lncRNA and mRNA in different modules. PDA cells and tissues were used to validate the analysis results. Finally, we found that NONHSAT185150.1 and B4GALT6 were negatively correlated with MEK1/2. By analyzing GSE45765, the genome-wide profiles of lncRNA–mRNA network after MEK1/2 was established, which might aid the development of drug-targeting MEK1/2 and the investigation of diagnostic markers.  相似文献   
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