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排序方式: 共有10000条查询结果,搜索用时 281 毫秒
941.
Daniel Duran Xue Zeng Sheng Chih Jin Jungmin Choi Carol Nelson-Williams Bogdan Yatsula Jonathan Gaillard Charuta Gavankar Furey Qiongshi Lu Andrew T. Timberlake Weilai Dong Michelle A. Sorscher Erin Loring Jennifer Klein August Allocco Ava Hunt Sierra Conine Jason K. Karimy Kristopher T. Kahle 《Neuron》2019,101(3):429-443.e4
942.
Shiyue Cheng Zhi Li Junju He Shujun Fu Yumei Duan Qin Zhou Yuanliang Yan Xiaoyu Liu Liyu Liu Chang Feng Lu Zhang Jiang He Yuezhen Deng Lun-Quan Sun 《生物化学与生物物理学报:疾病的分子基础》2019,1865(6):1201-1213
Viral noncoding RNAs (Epstein–Barr virus-encoded RNAs, EBERs) are believed to play a critical role in the progression of lymphoma and nasopharyngeal carcinoma (NPC). However, the accurate mechanisms accounting for their oncogenic function have not been elucidated, especially in terms of interaction between tumor cells and mesenchymal cells. Here, we report that, in addition to NPC cells, EBERs are also found in endothelial cells in Epstein–Barr virus (EBV)-infected NPC parenchymal tissues, which implicates NPC-derived extracellular vesicles (EVs) in transmitting EBERs to endothelial cells. In support of this hypothesis, we first ascertained if EBERs could be transferred to endothelial cells via EVs isolated from NPC culture supernatant. Then, we clarified that EVs-derived EBERs could promote angiogenesis through stimulation of VCAM-1 expression. Finally, we explored the involvement of EBER recognition by TLR3 and RIG-I in NPC angiogenesis. Our observations collectively illustrate the significance and mechanism of EVs-derived EBERs in angiogenesis and underlie the interaction mechanisms between EBV-infected NPC cells and the tumor microenvironment. 相似文献
943.
944.
Caihong Yu Dong Ai Ronghua Lin Shenhang Cheng 《Archives of insect biochemistry and physiology》2019,100(4)
The purpose of this study was to evaluate the effects of three toxic β‐glucosides, phlorizin, santonin, and amygdalin, on carbohydrate metabolism in the cotton bollworm, Helicoverpa armigera (Hübner), when diets mixed with β‐glucosides were fed to third‐instar larvae. The growth of the larvae was significantly inhibited by exposure to santonin after 96 hr but not obviously affected by phlorizin and amygdalin. The midgut trehalase activities were only 51.7%, 32%, and 42.5% of that of the control after treatment with phlorizin, santonin and amygdalin at 2 mg/ml, respectively. In the hemolymph and fat body, the amount of trehalose decreased in all cases. However, the effects of santonin on the alteration of the glycogen and glucose levels as well as the activities of glycogen phosphorylase, were different than those of the other two β‐glucosides. It appears that the three β‐glucosides have different influences on the carbohydrate metabolism of cotton bollworm. 相似文献
945.
946.
947.
Yan-Hui Wang Hao-Yang Wu Dávid Rédei Qiang Xie Yan Chen Ping-Ping Chen Zhuo-Er Dong Kai Dang Jakob Damgaard Pavel Štys Yan-Zhuo Wu Jiu-Yang Luo Xiao-Ya Sun Viktor Hartung Stefan M. Kuechler Yang Liu Hua-Xi Liu Wen-Jun Bu 《Cladistics : the international journal of the Willi Hennig Society》2019,35(1):42-66
The phylogeny of true bugs (Hemiptera: Heteroptera), one of the most diverse insect groups in terms of morphology and ecology, has been the focus of attention for decades with respect to several deep nodes between the suborders of Hemiptera and the infraorders of Heteroptera. Here, we assembled a phylogenomic data set of 53 taxa and 3102 orthologous genes to investigate the phylogeny of Hemiptera–Heteroptera, and both concatenation and coalescent methods were used. A binode-control approach for data filtering was introduced to reduce the incongruence between different genes, which can improve the performance of phylogenetic reconstruction. Both hypotheses (Coleorrhyncha + Heteroptera) and (Coleorrhyncha + Auchenorrhyncha) received support from various analyses, in which the former is more consistent with the morphological evidence. Based on a divergence time estimation performed on genes with a strong phylogenetic signal, the origin of true bugs was dated to 290–268 Ma in the Permian, the time in Earth's history with the highest concentration of atmospheric oxygen. During this time interval, at least 1007 apomorphic amino acids were retained in the common ancestor of the extant true bugs. These molecular apomorphies are located in 553 orthologous genes, which suggests the common ancestor of the extant true bugs may have experienced large-scale evolution at the genome level. 相似文献
948.
The avian circadian rhythm pacemaker is composed of the retina, pineal gland and suprachiasmatic nucleus. As an intact input-pacemaker-output system, each of these structures is linked within a neuroendocrine loop to influence downstream processes and peripheral oscillations. While our previous study found that monochromatic light affected the circadian rhythms of clock genes in the chick retina, the effect of the pineal gland on the response of the retinal circadian clock under monochromatic light still remains unclear. In this study, a total of 144 chicks, including sham-operated and pinealectomized groups, were exposed to white, red, green or blue light. After 2 weeks of light illumination, the circadian expression of six core clock genes (cClock, cBmal1, cCry1, cCry2, cPer2 and cPer3), melanopsin (cOpn4-1, cOpn4-2), Arylalkylamine N-acetyltransferase (cAanat) and melatonin was examined in the retina. The cBmal1, cCry1, cPer2, cPer3, cOpn4-1, cOpn4-2 and cAanat genes as well as melatonin had circadian rhythmic expression in both the sham-operated and pinealectomized groups under different monochromatic lights, while cClock and cCry2 had arrhythmic 24 h profiles in all of the light-treated groups. After pinealectomy, the rhythmicity of the clock genes, melanopsins, cAanat and melatonin in the chick retina did not change, especially the mesors, amplitudes and phases of cBmal1, cOpn4-1, cOpn4-2, cAanat and melatonin. Compared to the white light group, however, green light increased the mRNA expression of the positive-regulating clock genes cBmal1, cAanat, cOpn4-1 and cOpn4-2 as well as the melatonin content in pinealectomized chicks, whereas red light decreased their expression. These results suggest that the chick retina is a relatively independent circadian oscillator from the pineal gland, whose circadian rhythmicity (including photoreception, molecular clock and melatonin output) is not altered after pinealectomization. Moreover, green light increases ocular cAanat expression and melatonin synthesis by accelerating the expression of melanopsin and positive-regulating clock genes cBmal1 and cClock. 相似文献
949.
Xianjun Sun Yubao Lv Junjun Wang HuiQin Cheng Jianhua Huang Yijie Du Jingcheng Dong 《Journal of cellular biochemistry》2019,120(10):18128-18141
Clinical application of oxaliplatin, a platinum-based chemotherapeutic agent, in cancer, especially colorectal cancer, is widely used. However, oxaliplatin-induced peripheral neurotoxicity (OIPN) has a high incidence, and to date, there have been few detailed studies on pathogenesis and treatment mechanisms. The present study was performed by using a proteomic approach to explore protein expression profiling of rats treated with oxaliplatin by multiplex isobaric tags for relative and absolute quantification labeling and two-dimensional liquid chromatography-tandem mass spectrometry. There were 74 proteins that showed different expression in sciatic nerve between control rats and OIPN model rats, with 53 upregulated proteins and 21 downregulated proteins detected in OIPN groups compared with control groups. On the basis of Gene Ontology clustering, these proteins were associated with biological processes (eg, muscle contraction, muscle system process, and skeletal muscle contraction), cellular component (eg, myofibril, contractile fiber, and contractile fiber part) and molecular function (structural constituent of muscle, hydro-lyase activity, and calcium ion binding). On the basis of Kyoto Encyclopedia of Genes and Genomes pathway database, these proteins were associated with African trypanosomiasis, malaria, nitrogen metabolism, etc. Real-time polymerase chain reaction, Western blot as well as immunohistochemistry analysis was performed to examine the expression of partially differential protein. In conclusion, our study establishes a protein expression profile of oxaliplatin-induced rats and mechanisms leading to OIPN development, and will be useful for developing novel diagnostic biomarkers and aiding in the prevention and control of OIPN. 相似文献
950.