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951.
Liu Y Wang M Xue M Li Y Li X Ruan J Liu K 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2008,873(1):41-50
The structural elucidation of metabolites of penehyclidine in rats, a novel anti-cholinergic drug, by the method of liquid chromatography-electrospray ionization mass spectrometry, gas chromatography-mass spectrometry with electron impact ion source and stable isotope ion cluster was described. Identification and elucidation of the phase I and phase II metabolites were performed by comparing the daughter ion pairs of stable isotope cluster, changes of the protonated molecular masses, full scan MS(n) spectra and retention times with those of the parent drug, penehyclidine and penehyclidine deuterium-labeled. Penehyclidine was easily biotransformed by the pathways of oxidative, hydroxylated, methoxylated and phase II conjugated reactions to form several metabolites that retained the some features of the parent molecules. Twelve metabolites (penehyclidine monoxide, hydroxypenehyclidine, penehyclidine dioxide, hydroxypenehyclidine monoxide, dihydroxypenehyclidine, dihydroxypenehyclidine (position isomer), dihydroxypenehyclidine monoxide, trihydroxypenehyclidine, methoxypenehyclidine dioxide, dimethoxypenehyclidine, trihydroxymethoxypenehyclidine and glucuronide conjugated hydroxypenehyclidine) were identified. The results from electrospray ion and electron impact ion data with the stable isotope cluster showed the qualitative differences in the mass spectral patterns, suggesting that these technologies should be used in parallel to ensure comprehensive metabolites detection and characterization. The described method has wide applicability to rapidly screen and provide structural information of metabolites. 相似文献
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955.
Effects of Irrigation and Nitrogen on the Performance of Aerobic Rice in Northern China 总被引:1,自引:0,他引:1
Chang-Ying Xue Xiao-Guang Yang B.A.M. Bouman Wei Deng Qiu-Ping Zhang Jie Yang Wei-Xiong Yan Tian-Yi Zhang A-Ji Rouzi Hua-Qi Wang Pu Wang 《植物学报(英文版)》2008,50(12):1589-1600
Aerobic rice is a new production system in which specially-developed varieties are grown under non-flooded, non-puddled, and non-saturated soil conditions. In 2003-2004, irrigation x Nitrogen experiments were carried out near Beijing using variety HD297. Water treatments included four irrigation levels, and Nitrogen treatments included different fertilizer N application rates and different numbers of N splits. The highest yields were 4460 kg/ha with 688 mm of total (rain plus irrigation) water input in 2003 and 6 026 kg/ha with 705 mm of water input in 2004. Because of the quite even distribution of rainfall in both years, the four irrigation treatments did not result in large differences of soil water conditions. There were few significant effects of irrigation on biomass accumulation, but yield increased with the total amount of water applied. High yields coincided with high harvest index and high percentages of grain filling. The application of fertilizer N either reduced biomass and yield or kept it at the same level as 0 N and consistently reduced the percentage grain filling and 1 000-grain weight. With the highest water application, five splits of N gave higher yield than three splits, whereas three splits gave higher yield than five splits with lower water applications. 相似文献
956.
Zhang Y Zhang X Xia H Xue Y Wang J Tian B Wei Z Lu C 《Acta biochimica et biophysica Sinica》2008,40(6):533-538
Cassettes harboring luciferase reporter driven by Bombyx mori cytoplasmic actin gene promoter (A3) (671 bp) and B. mori nuclear polyhedrosis virus immediate-early promoter (IE-1) (580 bp) were transferred to the bacmid AcΔEGT to generate the recombinant Autographa californica nuclear polyhedrosis viruses, AcNPVA3Luc and AcNPVIELuc, respectively. Recombinant baculoviruses were injected into the hemocoele of newly ecdysed 5th instar larvae. The activities of the A3 and IE-1 promoters in various tissues were measured by luciferase activity assay and normalized by the copy number of recombinant virus. Results showed that the activity of the A3 promoter was approximately 10-fold higher than the IE-1 promoter. The promoter activities of A3 and IE-1 were highest in the silk gland, followed by fat body, middle gut, Malpighian tubule, and hemocyte. In silk gland, activity of the two promoters was highest in posterior silk gland, followed by middle and anterior silk glands. The difference in promoter activities reflects the growth speed of tissue in silkworm larvae. The activity of the A3 promoter remained unchanged and was not inhibited significantly by viral factors at least 3–4 d post injection of rAcNPV. 相似文献
957.
目的:研究霉酚酸酯体外对细胞生长抑制率、细胞凋亡以及对细胞黏附率的影响.方法:以霉酚酸酯在0.1μg/ml-100μg/ml,24-72h内作用于肝癌细胞,MTT法检测肿瘤细胞的生长抑制率,流式细胞仪检测细胞周期,Hoeehst33258荧光染色观察细胞凋亡的形态变化,细胞黏附实验检测细胞黏附率的影响.结果:霉酚酸酯显著的抑制了肿瘤细胞的增长,并显著的抑制其黏附率,在浓度为100μg/ml作用72小时时生长抑制率达78.8%,黏附率降低至42.1%,Hoechst33258染色实验发现随浓度增大细胞凋亡的发生增多,核固缩、核碎裂的现象发生越明显.流式细胞仪检测,细胞周期阻滞于GO/G1期,减少增殖细胞在S期的分布.结论:霉酚酸酯对肝癌细胞HepG-2的增长具有明显的抑制作用. 相似文献
958.
Calcineurin B-like interacting protein kinase OsCIPK23 functions in pollination and drought stress responses in rice (Oryza sativa L.) 总被引:2,自引:0,他引:2
Wenqiang Yang Zhaosheng Kong Edith Omo-Ikerodah Wenying Xu Qun Li Yongbiao Xue 《遗传学报》2008,35(9):531-43, S1-2
Droughtis very harmful to grain yield due to its adverse effect on reproduction,especially on pollination proeess in rice.However,the molecular basis of such an effect still remains largely unknown.Here,wereport the role of amember of CBL(Calcineurin B-Like)Interacting Protein Kinase(CIPK)family,OsCIPK23,in pollination and stress responses in dee.Molecular analyses revealed that it is mainly expressed in pistil and anther but up-regulated by pollination,as well as by treatments of various abiotic stresses and phytohormones.RNA interference-mediated suppression of OsCIPK23 expression significantly reduced seed set and conferred a hypersensitive response to drought stress,indicating its possible roles in pollination and drought stress.In consistent,overexpression of OsCIPK23 induced the expression of seVeral drought tolerance related genes.Taken together,these results indicate that OsCIPK23 is a multistress induced gene and likely mediatesa signaling pathway commonly shared by both pollination and drought stress responses in rice. 相似文献
959.
Identification of quantitative trait loci for four morphologic traits under water stress in rice (Oryza sativa L.) 总被引:1,自引:0,他引:1
Bing Yue Weiya Xue Lijun Luo Yongzhong Xing 《遗传学报》2008,35(9):569-575
Late season drought coinciding with the rice booting to heading stage affects the development of plant height,panicle exsertion,and flag leaf size,and causes significant yield loss.In this study,a recombinant inbred line population derived from a cross between paddy and upland cultivars was used for data collection of the morphologic traits under well water and drought stress conditions.bought stress was applied at the stage of panicle initiation in the field in 2002 and at the booting stage in PVC pipes in 2003.The data from stress con ditions and their ratios(tait measured under stress condition/trait measured under well water condition)or differences(trait measured under stress condition minus trait measured under well water condition)were used for OTL analysis.Totally,17 and 36 QTLs for these traits were identified in 2002 and 2003,respectively,which explained a range of 2.58%-29.82%Of the phenotypic variation.Among them,six QTLs were commonly identified in the two years,suggesting that the drought stress in the two years was different.The genetic basis of these traits will provide useful information for improving rice late season drought resistance,and their application as indirect indices in rice late season drought resistance screening was also discussed. 相似文献
960.
The present paper reports case study results of the risk assessment of transgenic Bt cotton on a non-target pest, cotton aphid, Aphis gossypii. Several types of techniques, i.e., electrical penetration graph (EPG), light and electron microscopy, bioassays and chemical analysis, were applied to investigate physical and chemical leaf factors of 2 transgenic Bt cotton lines (GK12 and GK19) and their pa-rental non-Bt cotton line (Simian3) associated with searching and feeding behaviors of cotton aphids on leaves or leaf extracts of cotton plants. EPG results showed that there were some differences among behaviors of cotton aphids on 2 Bt cotton and 1 non-Bt cotton lines. Cotton aphids performed similarly to leaf surface extracts from 3 cotton lines; and leaf surface chemicals, mainly volatiles and waxes, were almost identical in the components and concentrations among the cotton lines. However, three cotton lines were quite different from each other in the densities of certain kinds of covering trichomes. Therefore, the relationships between the physical characteristics and the searching behaviors of cotton aphids on the three cotton lines were constructed as the regression equations. Glandular trichomes and covering trichomes with 5 branches influenced the cotton aphids' searching behaviors effectively; and other trichomes with other branches affected aphids in varying ways. These results demonstrated that leaf surface physical factors of transgenic Bt cotton lines different from their parental non-Bt line could affect the penetration behaviors of non-target cotton aphids. Cotton aphids penetrate and feed more easily on two Bt cotton lines than on the non-Bt cotton line. 相似文献