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71.
棉铃虫的取食营养特点与棉花抗虫素分布的关系 总被引:1,自引:1,他引:0
通过研究棉花8个部位对棉铃虫Helicoverpa armzgera的营养效果和其所含次生物质类萜烯和单宁的浓度及在组织中的分布,揭示了棉铃虫取食营养特点与棉花次生化学的关系。棉铃虫取食顶尖、转移蛀食蕾铃的习性,与有关器官或组织对幼虫的营养效果密切相关,而营养效果主要取决于类萜烯和单宁的含量。棉花顶尖嫩叶中单宁浓度随着棉花的生长发育呈升高的趋势;类萜烯浓度在第四真叶期、第六真叶期和现蕾初期之间出现一个明显的底谷,而此期幼虫主要为害顶尖。蕾铃外层的苞叶、花萼、花瓣和铃皮,因次生物质含量高,不利于幼虫生长,相反内部的花粉、子房和铃心,次生物质含量低,营养效果好,顶尖嫩叶则介于其间。类萜烯存在于组织的色素腺内,分布集中;单宁则散布于组织中,偏多分布于组织外层。结果证实,昆虫在寄主植物上的取食方式是昆虫对寄主体内变动的次生化学的一种适应,它使昆虫付出尽少代价获得最适营养效果。 相似文献
72.
Long Ma Qiushi Ruan Wenwen Zha Lingqiao Kong ZhengMing Sun 《Liver Transplantation》2024,14(11):2303586
Photo-assisted ion batteries demonstrate remarkable potential for portable and decentralized solar energy utilization, due to their profound capacity enhancement under irradiation accompanied by promoted discharge voltages. However, ion batteries in practice are highly compact with limited surface area for irradiation. Overcoming the size limit for irradiation is a challenge. Herein, an irradiation spillover effect in photo-assisted ion batteries is demonstrated, that is the impact of irradiation on the battery is not restrained within the irradiated area but can spillover the whole electrode. This phenomenon is a consequence of the light-induced potential difference between irradiated and unirradiated regions, leading to selective ion insertion. Irradiated regions favored H+ insertion due to light-induced proton-coupled electron transfer, while unirradiated regions preferred Zn2+ insertion. Consequently, the capacity enhancement remains unaffected by halving the irradiated area. This study overcomes the irradiation size limit for photo-assisted ion batteries and encourages highly integrated photo-assisted ion batteries for practice application. 相似文献
73.
Lie‐Feng Ma Peng‐Fei Wang Ji‐Dong Wang Xiang‐Min Tong Wei‐Guang Shan Hui Zhang Zha‐Jun Zhan 《化学与生物多样性》2017,14(8)
Three new sesquiterpenoids, salplebeones A – C ( 1 – 3 ), were isolated from the ethanol‐soluble extract of the aerial part of Salvia plebeia R. Br . Their structures were established by detailed analysis of NMR and MS spectra. Salplebeone A was an eudesmane lactone, while salplebeones B and C were rare eudesmane sesquiterpenoids, containing 12,8‐lactam groups. Antiproliferative activities of salplebeones A – C to myeloid leukemia cell lines were evaluated. 相似文献
74.
75.
Li G Alt FW Cheng HL Brush JW Goff PH Murphy MM Franco S Zhang Y Zha S 《Molecular cell》2008,31(5):631-640
Mutations in XLF/Cernunnos (XLF) cause lymphocytopenia in humans, and various studies suggest an XLF role in classical nonhomologous end joining (C-NHEJ). We now find that XLF-deficient mouse embryonic fibroblasts are ionizing radiation (IR) sensitive and severely impaired for ability to support V(D)J recombination. Yet mature lymphocyte numbers in XLF-deficient mice are only modestly decreased. Moreover, XLF-deficient pro-B lines, while IR-sensitive, perform V(D)J recombination at nearly wild-type levels. Correspondingly, XLF/p53-double-deficient mice are not markedly prone to the pro-B lymphomas that occur in previously characterized C-NHEJ/p53-deficient mice; however, like other C-NHEJ/p53-deficient mice, they still develop medulloblastomas. Despite nearly normal V(D)J recombination in developing B cells, XLF-deficient mature B cells are moderately defective for immunoglobulin heavy-chain class switch recombination. Together, our results implicate XLF as a C-NHEJ factor but also indicate that developing mouse lymphocytes harbor cell-type-specific factors/pathways that compensate for the absence of XLF function during V(D)J recombination. 相似文献
76.
Zha Renming Ling Yinghua Yang Zhenglin Zhao Fangming Zhong Bingqiang Xie Rong Sang Xianchun He Guanghua 《Molecular breeding : new strategies in plant improvement》2008,22(3):467-476
One hundred and fifty-one rice hybrids produced in two sets of half-dialell crosses and their parents (13 cytoplasmic male
sterile lines and 19 restorers) were used to predict the F1 performances of seven yield traits through the parental genetic distances (GD) based on SSR markers. The positive loci (PL)
and effect-increasing loci (IL), which were screened from SSR polymorphic loci by the F1 traits of 32 parents, together with total loci (TL), were utilized to estimate parental GD and the models were found to predict
the traits of hybrids derived from different parents, fixed parents, and different environments, respectively. The results
were as follows: (1) 550 polymorphic loci were detected from 174 SSR markers: a dendrogram based on these loci could separate
all the sterile and restorer lines used in the present study, which indicated that parental genetic diversity of F1 was large; (2) the correlations between F1 traits and parental GDs based on IL ranged from 0.61 to 0.87 with a mean of 0.76, and they were higher than those on TL or
on PL; (3) predictions based on IL for F1 traits (except grain weight per plant) derived from different environments were ideal, but worse for F1 traits derived from different parents; and (4) IL was more effective than TL and PL in predicting traits of F1 with fixed parents, and predictions for fixed restorer combinations were more effective than those for fixed sterile line
combinations. These results should facilitate molecular prediction for hybrid yield and other traits by means of both elite
sterile and restorer lines. 相似文献
77.
78.
Xingfu Zha Qingyou Xia Jun Duan Chunyun Wang Ningjia He Zhonghuai Xiang 《Insect biochemistry and molecular biology》2009,39(5-6):315-321
In many organisms, dosage compensation is needed to equalize sex-chromosome gene expression in males and females. Several genes on silkworm Z chromosome were previously detected to show a higher expression level in males and lacked dosage compensation. Whether silkworm lacks global dosage compensation still remains poorly known. Here, we analyzed male:female (M:F) ratios of expression of chromosome-wide Z-linked genes in the silkworm using microarray data. The expression levels of genes on Z chromosome in each tissue were significantly higher in males compared to females, which indicates no global dosage compensation in silkworm. Interestingly, we also found some genes with no bias (M:F ratio: 0.8–1.2) on the Z chromosome. Comparison of male-biased (M:F ratio more than 1.5) and unbiased genes indicated that the two sets of the genes have functional differences. Analysis of gene expression by sex showed that M:F ratios were, to some extent, associated with their expression levels. These results provide useful clues to further understanding roles of dosage of Z chromosome and some Z-linked sexual differences in silkworms. 相似文献
79.
80.
Bei Yan JiYe A HaiPing Hao GuangJi Wang XuanXuan Zhu WeiBin Zha LinSheng Liu EnZe Guan Ying Zhang ShengHua Gu Qing Huang YuanTing Zheng 《中国科学:生命科学英文版》2009,52(11):1081-1090
The traditional Chinese medicine concepts of “Xinxueyuzuzheng (heart blood stasis obstruction pattern)” and “Qiyinliangxuzheng (qi and yin deficiency pattern)” for myocardial ischemia rat models were constructed in the present study. Endogenous metabolites in rat plasma were analyzed using the GC/TOF-MS-based metabonomic method. Significant metabolic differences were observed between the control and two model groups, and the three groups were distinguished clearly by pattern recognition. Compared with those of the control, the levels of hydroxyproline, threonic acid, glutamine and citric acid were strikingly up- or down-regulated in model rats. The metabolites contributing most to the classification between the two “pattern” rats were identified, such as valine, serine, threonine, ornithine, hydroxyproline, lysine, 2-hydroxybutanoic acid, 3-hydroxybutanoic acid, galactofuranose and inositol. These compounds were indicated as the potential biomarkers. The results suggested that the two “patterns” are involved in dysfunction in oxidative stress, energy metabolism and amino acid metabolism. These findings also provided the substantial foundation for exploring the scientific connotation of these two “Zhengxing (pattern types)” of myocardial ischemia, and “Bianzheng (pattern identification)”. 相似文献