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61.
记述采自河南省蚱科二新种,即鸡公山蚱Tetrix jigongshanensis sp. nov.和突背蚱Tetrix glochinota sp. nov..鸡公山蚱近似于凹额蚱Tetrix cavifrontalis Liang, 1998, 主要区别为:1)头顶前缘平直;2)侧面观,头顶与额面隆起呈钝角形;3)侧面观,额面隆在侧单眼前直,不凹陷;4)侧观,前胸背板上缘呈弧形;5)前胸背板前缘钝角形突出;6)后突到达后足股节中部;7)后翅略不到达后突顶端;8)中足股节明显宽于前翅宽.突背蚱近似于仿蚱Tetrix simulans(B.-Bienko, 1929)及云龙蚱Tetrix yunlongensis Zheng et Mao, 2002, 其与二者的区别为:1)头顶前缘平直;2)侧面观,背板上缘前半部球形突出,后半段平直;3)后突到达后足股节顶端.其区别于前者为:1)侧面观,额面隆起在侧单眼前凹陷;2)中足股节宽于前翅等宽.其区别于后者为头顶宽为一眼宽的1.7倍.模式标本保存于陕西师范大学动物研究所昆虫标本室. 相似文献
62.
Jing Guo Tomer Fishman Yao Wang Alessio Miatto Wendy Wuyts Licheng Zheng Heming Wang Hiroki Tanikawa 《Journal of Industrial Ecology》2021,25(1):162-175
Construction materials are considerable forces of global environmental impacts, but their dynamics vis‐à‐vis urban development are poorly documented, in part because their long lifespans require elusive and sometimes nonexistent decade‐long high‐resolution data. This study analyzes the construction material flow and stock trends that shaped and were shaped by the development, decline, and renewal of the Tiexi district of Shenyang, a microcosm of China's urban transformations since the early 20th century. Chronicling building‐by‐building the material flows and stock accumulations involved in the buildup of this area, we shed light on the physical resource context of its socioeconomic history. We find that 42 million tonnes of construction materials were needed to develop the Tiexi district from 1910 to 2018, and 18 million tonnes of material outflows were generated by end‐of‐life building demolition. However, over 55% of inflows and 93% of outflows occurred since 2002 during a complete redevelopment of the district. Only small portions of end‐of‐life materials could have been reused or recycled because of temporal and typological mismatches of supply and demand and technical limitations. Our analysis reveals a dramatic decrease in median building lifetimes to as low as 6 years in the early 21st century. These findings contribute to the discussion of long‐term environmental efficiency and sustainability of societal development through construction and reflect on the challenges of urban renewal processes not only in China but also in other developing and developed countries that lost (or may lose) their traditional economic base and restructure their urban forms. This article met the requirements for a Silver/Silver JIE data openness badge described at http://jie.click/badges . 相似文献
63.
Hailan Yao Kechun Zhou Dong Yan† Mingtao Li‡ Yizheng Wang† 《Journal of neurochemistry》2009,108(4):909-919
Chronic loss of intracellular K+ can induce neuronal apoptosis in pathological conditions. However, the mechanism by which the K+ channels are regulated in this process remains largely unknown. Here, we report that the increased membrane expression of Kv2.1 proteins in cortical neurons deprived of serum, a condition known to induce K+ loss, promotes neuronal apoptosis. The increase in I K current density and apoptosis in the neurons deprived of serum were inhibited by a dominant negative form of Kv2.1 and MK801, an antagonist to NMDA receptors. The membrane level of Kv2.1 and its interaction with SNAP25 were increased, whereas the Kv2.1 phosphorylation was inhibited in the neurons deprived of serum. Botulinum neurotoxin, an agent known to prevent formation of soluble N -ethylmaleimide-sensitive factor attachment protein receptor complex, suppressed the increase in I K current density. Together, these results suggest that NMDA receptor-dependent Kv2.1 membrane translocation is regulated by a soluble N -ethylmaleimide-sensitive factor attachment protein receptor-dependent vesicular trafficking mechanism and is responsible for neuronal cell death induced by chronic loss of K+ . 相似文献
64.
脉冲电场对真皮成纤维细胞生长和膜流动性的影响 总被引:19,自引:0,他引:19
采用MTT比色分析法检测脉冲电场(f=50Hz,t=20μs,Epp=1V/m),对真皮成纤维细胞增殖的影响,结果表明,电场作用1分钟和5分钟,均产生促进细胞增殖的效果(P<0.05和P<0.001),而较长时间(t≥10分钟)的电场作用则显著抑制细胞的正常增殖(P<0.001)。 采用荧光偏振法研究了脉冲电场对真皮成纤维细胞膜流动性的影响。结果表明,电场作用5分钟后即刻引起膜流动性的显著增加。而电场作用45分钟后,需经过一段时间的温育(30 分钟),才表现出膜流动性的降低。说明不同作用时间的电场可以造成膜流动性的增加或降低,而且对膜流动性的影响是可逆的。我们认为,脉冲电场所引起的膜流动性改变是细胞分裂能力发生变化的原因之一。 相似文献
65.
Zhang W Yue B Wang X Zhang X Xie Z Liu N Fu W Yuan Y Chen D Fu D Zhao B Yin Y Yan X Wang X Zhang R Liu J Li M Tang Y Hou R Zhang Z 《Molecular biology reports》2011,38(7):4257-4264
In order to investigate the mitochondrial genome of Panthera tigris amoyensis, two South China tigers (P25 and P27) were analyzed following 15 cymt-specific primer sets. The entire mtDNA sequence was found to be 16,957 bp and 17,001 bp long for P25 and P27 respectively, and this difference in length between P25 and P27 occurred in the number of tandem repeats in the RS-3 segment of the control region. The structural characteristics of complete P. t. amoyensis mitochondrial genomes were also highly similar to those of P. uncia. Additionally, the rate of point mutation was only 0.3% and a total of 59 variable sites between P25 and P27 were found. Out of the 59 variable sites, 6 were located in 6 different tRNA genes, 6 in the 2 rRNA genes, 7 in non-coding regions (one located between tRNA-Asn and tRNA-Tyr and six in the D-loop), and 40 in 10 protein-coding genes. COI held the largest amount of variable sites (9 sites) and Cytb contained the highest variable rate (0.7%) in the complete sequences. Moreover, out of the 40 variable sites located in 10 protein-coding genes, 12 sites were nonsynonymous. 相似文献
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A novel approach was developed for predicting the structural classes of proteins based on their sequences. It was assumed that proteins belonging to the same structural class must bear some sort of similar texture on the images generated by the cellular automaton evolving rule [Wolfram, S., 1984. Cellular automation as models of complexity. Nature 311, 419-424]. Based on this, two geometric invariant moment factors derived from the image functions were used as the pseudo amino acid components [Chou, K.C., 2001. Prediction of protein cellular attributes using pseudo amino acid composition. Proteins: Struct., Funct., Genet. (Erratum: ibid., 2001, vol. 44, 60) 43, 246-255] to formulate the protein samples for statistical prediction. The success rates thus obtained on a previously constructed benchmark dataset are quite promising, implying that the cellular automaton image can help to reveal some inherent and subtle features deeply hidden in a pile of long and complicated amino acid sequences. 相似文献
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70.
Arabidopsis Elongator subunit 2 positively contributes to resistance to the necrotrophic fungal pathogens Botrytis cinerea and Alternaria brassicicola 下载免费PDF全文