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排序方式: 共有734条查询结果,搜索用时 46 毫秒
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We investigated the structure and seasonality of the proximity network in a group of polygynous western black crested gibbons (Nomascus concolor) using social network analysis. The spatial proximity changed seasonally and was affected by temperature and rainfall. Preferred proximity association was not distributed randomly among individuals. Kinship was one explanation for the social structure, as offspring preferred to maintain close proximity with their mothers. The proximity of infants to mothers decreased with age, and independent offspring had lower proximity to mothers than dependent ones. We found that the adult male had different proximity relationships with two different adult females. The frequency of proximity between the male and the infant-carrying female was significantly higher than that between the male and the female who had immigrated carrying one offspring of uncertain paternity into the group. Infanticide avoidance and/or predation protection for dependent infants might explain the proximity relationship differences. Temperature influenced group proximity association, with individual proximity increasing in the cold months and decreasing in the hot months. Group proximity decreased in months with higher anthropogenic disturbance. 相似文献
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Guoxing Zheng Changying Jiang Yulin Li Dandan Yang Youcai Ma Bing Zhang Xuan Li Pei Zhang Xiaoyu Hu Xueqiang Zhao Jie Du Xin Lin 《蛋白质与细胞》2019,(2):104-119
Arrhythmogenic right ventricular dysplasia/cardiomyopathy(ARVD/C)is a genetic cardiac muscle disease that accounts for approximately 30%sudden cardiac death in young adults.The Ser358Leu mutation of transmembrane protein 43(TMEM43)was commonly identified in the patients of highly lethal and fully penetrant ARVD subtype,ARVD5.Here,we generated TMEM43 S358L mouse to explore the underlying mechanism.This mouse strain showed the classic patholo.gies of ARVD patients,including structural abnormalities and cardiac fibrofatty.TMEM43 S358L mutation led to hyper-activated nuclear factor kB(NFkB)activation in heart tissues and primary cardiomy.ocyte cells.Importantly,this hyper activation of NF-κB directly drove the expression of pro-fibrotic gene,transforming growth factor beta(TGFβ),and enhanced downstream signal,indicating that TMEM43 S358L mutation up-regulates NF-κB-TGFβ signal cascade during ARVD cardiac fibrosis.Our study partially reveals the regulatory mechanism of ARVD development. 相似文献
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Shuting Yu ZhiYong Sun Xiuzhu Wang Tiantian Ju Changhao Wang Yingqi Liu Zhezhe Qu KuiWu Liu Zhongting Mei Na Li Meixi Lu Fan Wu Min Huang Xiaochen Pang Yingqiong Jia Ying Li Yaozhi Zhang Shunkang Dou Jianhao Jiang Xin Li Baofeng Yang Weijie Du 《中国科学:生命科学英文版》2023,(12):2786-2804
Ischemic heart failure(HF) remains a leading cause of morbidity and mortality. Maintaining homeostasis of cardiac function and preventing cardiac remodeling deterioration are critical to halting HF progression. Methyltransferase-like protein 13(Mettl13) has been shown to regulate protein translation efficiency by acting as a protein lysine methyltransferase, but its role in cardiac pathology remains unexplored. This study aims to characterize the roles and mechanisms of Mettl13 in cardiac contra... 相似文献
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Jie Tang Yi-Cheng Ma Yuan-Li Chen Rui-Qiu Yang Heng-Chen Liu Xin Wang Baosen Ni Cheng-Gang Zou Ke-Qin Zhang 《中国科学:生命科学英文版》2023,(3):439-452
The maintenance of proteostasis is essential for cellular and organism healthspan. How proteostasis collapse influences reproductive span remains largely unclear. In Caenorhabditis elegans, excess accumulation of vitellogenins, the major components in yolk proteins, is crucial for the development of the embryo and occurs throughout the whole body during the aging process.Here, we show that vitellogenin accumulation leads to reproduction cessation. Excess vitellogenin is accumulated in the intest... 相似文献
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Xinxin Wang Xin Ma Gaobo Wei Weirui Ma Zhen Zhang Xuepeng Chen Lei Gao Zhenbo Liu Yue Yuan Lizhi Yi Jun Wang Toshinobu Tokumoto Junjiu Huang Dahua Chen Jian Zhang Jiang Liu 《基因组蛋白质组与生物信息学报(英文版)》2021,19(1):48-63
DNA methylation is a prevalent epigenetic modification in vertebrates, and it has been shown to be involved the regulation of gene expression and embryo development. However, it remains unclear how DNA methylation regulates sexual development, especially in species without sex chromosomes. To determine this, we utilized zebrafish to investigate DNA methylation reprogramming during juvenile germ cell development and adult female-to-male sex transition.We reveal that primordial germ cells(PGCs) undergo significant DNA methylation reprogramming during germ cell development, and the methylome of PGCs is reset to an oocyte/ovary-like pattern at 9 days post fertilization(9 dpf). When DNA methyltransferase(DNMT) activity in juveniles was blocked after 9 dpf, the zebrafish developed into females. We also show that Tet3 is involved in PGC development. Notably, we find that DNA methylome reprogramming during adult zebrafish sex transition is similar to the reprogramming during the sex differentiation from 9 dpf PGCs to sperm. Furthermore, inhibiting DNMT activity can prevent the female-to-male sex transition, suggesting that methylation reprogramming is required for zebrafish sex transition. In summary, DNA methylation plays important roles in zebrafish germ cell development and sexual plasticity. 相似文献
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Bioactive constituents from gum guggul (Commiphora wightii) 总被引:2,自引:0,他引:2
Zhu N Rafi MM DiPaola RS Xin J Chin CK Badmaev V Ghai G Rosen RT Ho CT 《Phytochemistry》2001,56(7):723-727
Bioactivity-directed fractionation and purification afforded cytotoxic components of Commiphora wightii. The exudates of C. wightii were extracted with EtOAc and the extract was subjected to repeated column chromatography. A fraction showing cytotoxic activity was characterized as a mixture of two ferulates with an unusual skeleton by spectral and chemical methods, including by NMR, GC-MS and chemical derivatization. This fraction also showed moderate scavenging effect against 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals. 相似文献
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