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901.
This study aimed to investigate the beneficial role of Millettia ferruginea extract (MF) in preventing cisplatin (Cisp) induced nephrotoxicity in rats. A total of 55 metabolites were identified using LC-MS analysis. The in vivo results indicated that MF pretreatment for 4 weeks (20 mg/kg b.w.) remarkably attenuated the altered renal biomarkers by decreasing the levels of plasma creatinine, urea, and uric acid when compared to the Cisp-group. The nephroprotective capacity of MF was further strengthened by histopathological observations, where Cisp + MF treated rats showed lower number of inflammatory cells and tubular degenerative changes than the Cisp-group. The harmful effects of cisplatin on renal oxidative stress indicators (MDA, SOD, CAT, and GPx), were restored by the treatment of MF. In addition, the reduction of inflammatory markers (IL-6 and TNF-α), associated with alleviating DNA fragmentation, highlighted the preventive effect of MF in kidney tissue. Additionally, MF components presented lower binding energies when docked into the active site of TNF-α and IL-6. The present findings concluded that M. ferruginea extract exhibited nephroprotective potential, which may be attributed to its antioxidant and anti-inflammatory properties. Further work is recommended to confirm the current results, explore the involved mechanism of action, and determine the therapeutic doses and time.  相似文献   
902.
基于朗伯-比尔定律与互补色原理,利用QQ截图读取色块RGB三原色组成的功能,获得不同亚甲基蓝浓度色阶对应的红色和绿色信号,设计了亚甲基蓝测定的简易紫外-可见分光光度法实验方案。该方案包括标准色阶制作、颜色信号读取、标准曲线绘制,以及待测样品测试等。通过学生实验,获得了满意的可靠性。该实验方案尤其适用于线上教学或缺少分光光度计的线下教学。  相似文献   
903.
This study analyzed the electrical properties of a multiple‐cells using the electric cell‐substrate impedance sensing, a scalable three‐dimensional electrode array and an equivalent circuit model (ECM). The experimental results validated the accuracy and validity of the extraction method for the ECM. The ECM simulation results using the electrical properties extracted by measuring 52 HeLa cells successfully forecasted the impedance magnitudes and phases for 15, 29, 78, and 98 HeLa cells. Comparing the ECM simulations and measurements, the maximum average errors in magnitude and phase were 3.06 % and 4.67 %, suggesting the number of HeLa cells can be classified by their electrical properties.  相似文献   
904.
A new Reverse Monte Carlo (RMC) package “fullrmc” for atomic or rigid body and molecular, amorphous, or crystalline materials is presented. fullrmc main purpose is to provide a fully modular, fast and flexible software, thoroughly documented, complex molecules enabled, written in a modern programming language (python, cython, C and C++ when performance is needed) and complying to modern programming practices. fullrmc approach in solving an atomic or molecular structure is different from existing RMC algorithms and software. In a nutshell, traditional RMC methods and software randomly adjust atom positions until the whole system has the greatest consistency with a set of experimental data. In contrast, fullrmc applies smart moves endorsed with reinforcement machine learning to groups of atoms. While fullrmc allows running traditional RMC modeling, the uniqueness of this approach resides in its ability to customize grouping atoms in any convenient way with no additional programming efforts and to apply smart and more physically meaningful moves to the defined groups of atoms. In addition, fullrmc provides a unique way with almost no additional computational cost to recur a group's selection, allowing the system to go out of local minimas by refining a group's position or exploring through and beyond not allowed positions and energy barriers the unrestricted three dimensional space around a group. © 2016 Wiley Periodicals, Inc.  相似文献   
905.
Poly(4‐methyl‐1‐pentene) (PMP) membranes were modified through isothermal annealing to investigate the change of their crystalline structure and rigid and mobile amorphous fractions (RAF and MAF), assuming a three‐phase model, affected the gas transport behavior. The crystalline structure was characterized by wide‐angle X‐ray diffraction (WAXD) and small‐angle X‐ray scattering (SAXS) techniques, and the free volume properties were analyzed by positron annihilation lifetime spectroscopy. Compared with the pristine membrane, the annealed membranes show higher crystallinity; the crystals undergo partial structural change from form III to form I. The lamellar crystal thickness, rigid amorphous fraction thickness, and long period in the lamellar stacks increase with crystallinity. The annealed PMP membranes exhibit higher permeability due to the increase in larger size free volumes in MAF and higher selectivity due to the increase in smaller size free volumes in RAF, respectively. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 2368–2376  相似文献   
906.
上世纪80年代以后进行的1∶20万水系沉积物扫面,个别元素分析质量不稳定,达不到设计要求,如镉、钴、铜、镧.利用大型分析仪器为手段,建立了稀有、稀散、稀土和铂族元素的测试方法,分析数据符合地球化学填图的要求,为地质找矿工作新的突破做出贡献.  相似文献   
907.
小组合作学习作为一种主动学习模式被引入到化学化工专业英语课程教学活动中,在具体教学实践中往往存在诸如分组随意、参与度低、分工不明确、缺乏有效评价、流于形式等诸多问题。对采用小组合作学习的班级进行问卷调查并分析统计结果,在此基础上提出合理分组、细致分工、适当指导、及时评价等解决方案,以期对小组合作学习实践教学活动提供相应的理论依据和实践基础。  相似文献   
908.
描述理想的低温等离子体中电磁波传播的模型是一个椭圆双曲混合型方程.证明了该方程闭Dirichlet问题弱解的存在唯一性.该结果关于区域的几何结构要求较少.由于这里所讨论的方程的奇异性与Keldysh方程的奇异性有相似性质,而后者的奇异性比Tricomi方程更强,因此关于其正则性的研究是很有意义的.作者给出了一个内正则性结果.  相似文献   
909.
This paper reveals the formation of annular lamellar body (ALB) in the ganglion of leech by means of in situ fixation and the lanthanum nitrate tracer technique. This formation involves both wrapping and internalization of the gap junctions between glial processes themselves, as well as between neuron and glial process. The results indicate that there is probably an active process of internalization of membrane structures involving gap junctions between neuron and glial cell in the central nervous system in leech. The functions of ALB are discussed.  相似文献   
910.
The high-level expression of recombinant gene products in the gramnegative bacteriumEscherichia coli often results in the misfolding of the protein of interest and its subsequent degradation by cellular proteases or its deposition into biologically inactive aggregates known as inclusion bodies. It has recently become clear that in vivo protein folding is an energy-dependent process mediated by two classes of folding modulators. Molecular chaperones, such as the DnaK-DnaJ-GrpE and GroEL-GroES systems, suppress off-pathway aggregation reactions and facilitate proper folding through ATP-coordinated cycles of binding and release of folding intermediates. On the other hand, folding catalysts (foldases) accelerate rate-limiting steps along the protein folding pathway such as thecis/trans isomerization of peptidyl-prolyl bonds and the formation and reshuffling of disulfide bridges. Manipulating the cytoplasmic folding environment by increasing the intracellular concentration of all or specific folding modulators, or by inactivating genes encoding these proteins, holds great promise in facilitating the production and purification of heterologous proteins. Purified folding modulators and artificial systems that mimic their mode of action have also proven useful in improving the in vitro refolding yields of chemically denatured polypeptides. This review examines the usefulness and limitations of molecular chaperones and folding catalysts in both in vivo and in vitro folding processes.  相似文献   
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