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91.
Ai  Xiaopeng  Dong  Xing  Guo  Ying  Yang  Peng  Hou  Ya  Bai  Jinrong  Zhang  Sanyin  Wang  Xiaobo 《Purinergic signalling》2021,17(2):229-240

Adenosine triphosphate (ATP) and its metabolites adenosine diphosphate, adenosine monophosphate, and adenosine in purinergic signaling pathway play important roles in many diseases. Activation of P2 receptors (P2R) channels and subsequent membrane depolarization can induce accumulation of extracellular ATP, and furtherly cause kinds of diseases, such as pain- and immune-related diseases, cardiac dysfunction, and tumorigenesis. Active ingredients of traditional Chinese herbals which exhibit superior pharmacological activities on diversified P2R channels have been considered as an alternative strategy of disease treatment. Experimental evidence of potential ingredients in Chinese herbs targeting P2R and their pharmacological activities were outlined in the study.

  相似文献   
92.
为了评估近20年来上海苏州河环境综合整治过程中鱼类多样性的变化状况, 本文于2019年6月(夏季)和9月(秋季)对苏州河13个断面的鱼类样本进行了采集, 对鱼类多样性和群落结构作了分析。结果显示, 2次采集共获得鱼类样本10,102号, 隶属于8目15科37属45种。夏季和秋季, 上游8个断面的鱼类均为36种, 下游5个断面则为12种和15种。从上游到下游, Shannon-Wiener多样性指数(H')、Margalef种类丰富度指数(D)和Simpson优势度指数(C)总体呈逐渐降低的趋势。相对重要性指数(IRI)显示, 夏秋两季上游断面共同的优势种为似鳊(Pseudobrama simoni), 下游为鲫(Carassius auratus)和泥鳅(Misgurnus anguillicaudatus)。丰度生物量曲线表明, 全河段鱼类群落结构总体上并不稳定, 特别是夏季的下游河段。Cluster聚类和非参数多维标度排序分析可明显将鱼类群落分为上游群组(I)与下游群组(II), 似鳊、泥鳅、鲫、光泽黄颡鱼(Pelteobagrus nitidus)和兴凯鱊(Acheilognathus chankaensis)等是造成群组间差异性的主要分歧种。与2001年的43种、2006年的28种相比, 本次调查的物种数出现了明显回升, 特别是下游河段。这种上游鱼类向下游迁移的趋势, 预示着下游中心城区与上游郊区河段的水质差别正在缩小, 水生态系统恢复迹象明显。本文认为, 上下游之间鱼类群落结构差异的缩小以及翘嘴鲌(Culter alburnus)、红鳍原鲌(Cultrichthys erythropterus)、棒花鱼(Abbottina rivularis)、子陵吻虾虎鱼(Rhinogobius giurinus)等在下游河段的出现, 可作为苏州河综合整治效果的重要生态标志。  相似文献   
93.
肠道菌群是人体内环境的重要组成部分,可影响机体的代谢、免疫和炎症反应,与原发性高血压的发生发展密切相关,已成为防治高血压的研究热点。中药在临床用于原发性高血压的治疗且疗效显著。研究表明中药可被肠道菌群分解代谢为易于吸收的活性物质,而这些活性物质又可通过调节肠道菌群结构及其代谢产物防治高血压。本文以肠道菌群作为切入点,通过分析肠道菌群与原发性高血压发生发展的关系和中药在调节原发性高血压肠道菌群方面的研究,总结中药通过调节肠道菌群防治原发性高血压的作用和机制,以期为中药防治高血压及药物研发提供新的研究思路。  相似文献   
94.
Russian Journal of Bioorganic Chemistry - The grape is a highly valuable food stuff owing to the presence of a number of biologically active substances, and vitamins occupy a special place among...  相似文献   
95.
In 2010–2011, experimental commercial cultivation of 14 species of hermatypic corals was carried out using the method of donor colony fragmentation. The transplants successfully survived on experimental frame installations. The coral colonies that were recovered from the fragments became attached to the frame installations in a similar way to their attachment on natural substrata. After 1 year, the size of the trans-plants was found to have increased by 275%. The newly formed artificial coral community was colonized by the damselfish Dascyllus reticulates (Pomacentridae); the species is a common coral fish species that lives on natural reefs.  相似文献   
96.
In July 2010, abnormally high water temperature (25–29°C), as well as increased biomass and phytoplankton production caused intensive development of heterotrophic bacteria and heterotrophic nanoflagellates. It was found that the abundance, biomass, and production of heterotrophic bacterioplankton, as well as the abundance and biomass of heterotrophic nanoflagellates, and the number of planktonic viruses, which were calculated on average for the reservoir under study, turned out to be higher in the years with lower water temperature (20–23°C). The virus-induced mortality of bacterioplankton in the Oka River and the Cheboksary Reservoir averaged 25.4 ± 3.4 and 22.4 ± 2.7% of the daily bacterioplankton production.  相似文献   
97.
The value of the voltage fall across the anode sheath is found as a function of the current density. Analytic solutions are obtained in a wide range of the ratio of the directed velocity of plasma electrons v 0 to their thermal velocity v T . It is shown that the voltage fall in a one-dimensional collisionless anode sheath is always negative. At the small values of v 0/v T , the obtained expression asymptotically transforms into the Langmuir formula. Generalized Bohm’s criterion for an electric discharge with allowance for the space charge density ρ(0), electric field E(0), ion velocity v i (0), and ratio v 0/v T at the plasma-sheath interface is formulated. It is shown that the minimum value of the ion velocity v i * (0) corresponds to the vanishing of the electric field at one point inside the sheath. The dependence of v i * (0) on ρ(0), E(0), and v 0/v T determines the boundary of the existence domain of stationary solutions in the sheath. Using this criterion, the maximum possible degree of contraction of the electron current at the anode is determined for a short high-current vacuum arc discharge.  相似文献   
98.
Results are presented from experimental studies of the structure of the compressed plasma of a Z-pinch produced during the implosion of a foam-wire load at the current of up to 3 MA. The foam-wire load consisted of two nested cylindrical cascades, one of which was a solid or hollow cylinder made of low-density agar-agar foam, while the other was a wire array. The wall thickness of a hollow foam cylinder was 100–200 μm. The images of the pinch and its spectrum obtained with the help of multiframe X-ray cameras and a grazing incidence spectrograph with a spatial resolution were analyzed. Data on the spatial structure of the emitting regions and the soft X-ray (SXR) spectrum of the Z-pinch in the final stage of compression of a foam-wire load were obtained. The implosion modes characterized by the formation of hot regions during implosion of such loads were revealed. The characteristic scale lengths of the hot regions were determined. It is shown that the energy distribution of SXR photons in the energy range from 80 eV to 1 keV forms the spatial structure of Z-pinch images recorded during the implosion of foam-wire loads. It is revealed that the spectral density of SXR emission in the photon energy range of 300–600 eV from hot Z-pinch regions exceeds the spectral density of radiation from the neighboring Z-pinch regions by more than one order of magnitude. Groups of lines related to the absorption and emission of radiation by atoms and multicharged ions of carbon and oxygen in the outer foam cascade of a foam-wire load were recorded for the first time by analyzing the spatial distribution of the SXR spectra of multicharged ions of the Z-pinch. The groups of absorption lines of ions (C III, O III, O IV, and O VI) corresponding to absorption of SXR photons in the Z-pinch of a tungsten wire array, which served as the inner cascade of a foam-wire load, were identified. The plasma electron temperature measured from the charge composition of carbon and oxygen ions in the outer agar-agar foam cascade was 10–40 eV. During the implosion of foam-wire loads at currents of up to 3 MA, SXR pulses (hν > 100 eV) with a duration of 10 ns and peak power of 3 TW were detected. It is shown that the temporal profile of single-peak and double-peak SXR pulses can be controlled by varying the parameters of the outer and inner cascades of the foam-wire load.  相似文献   
99.
100.
Results are presented from experiments on the formation of an internal electron transport barrier near the q = 1.5 rational surface in the T-10 tokamak. The experiments were carried out in the regime with off-axis electron cyclotron resonance (ECR) heating followed by a fast plasma current ramp-up. After suppressing sawtooth oscillations by off-axis ECR heating, an internal transport barrier began to form near the q = 1.5 rational surface. In the phase of the current ramp-up, the quality of the transport barrier improved; as a result, the plasma energy confinement time increased 2–2.5 times. The intentionally produced flattening of the profile of the safety factor q(r) insignificantly affected magnetohydrodynamic activity in the plasma column in spite of the theoretical possibility of formation of substantial m/n = 3/2 and 2/1 magnetic islands. Conditions are discussed under which the flattening of the profile of the safety factor q near low-order rational surfaces leads to the formation of either an internal transport barrier or the development of an island magnetic structure induced by tearing modes.  相似文献   
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