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放疗、化疗和选择性消化道净化对肠道的影响

中国临床营养杂志 2000年第3期8卷 147-150页

作者： johnlrombeauMD 王宝贵蒋朱明宾西法尼亚大学外科不详

放、化疗对骨髓造血组织和消化道上皮细胞的毒性作用,是治疗剂量的最重要限制因素.最近的研究集中在放、化疗引起小肠结构和功能变化的发病机制、临床表现和可恢复性上.另外,很多中心特别是欧洲正在应用选择性消化道净化(selective dige... 详细信息

放、化疗对骨髓造血组织和消化道上皮细胞的毒性作用,是治疗剂量的最重要限制因素.最近的研究集中在放、化疗引起小肠结构和功能变化的发病机制、临床表现和可恢复性上.另外,很多中心特别是欧洲正在应用选择性消化道净化(selective digestive decontamination, SDD),以期降低肠内毒性物质在应急时对肠道上皮细胞的毒性作用.本文综述放、化疗和选择性消化道净化剂,对肠道结构和功能变化的影响,以引起临床研究的重视.应用特殊的营养素和药物,防止或减轻上述情况对肠道功能损害将由其他同道讨论.

关键词：消化道化疗净化放疗骨髓造血组织肠道上皮细胞毒性作用治疗剂量发病机制功能变化小肠结构临床表现毒性物质多中心

Optimization of specific cell-peptide interactions at the bio-material interface via regulation of nonspecific biofouling interactions

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Science China Chemistry 2020年第2期63卷 143-144页

作者： john l.Brash Department of Chemical Engineering School of Biomedical EngineeringMcMaster University

Materials that interact with biological systems in a wellcontrolled,predictable manner are highly sought after for numerous biomedical and biotechnological *** example,it is essential that devices such as stents or heart valves in the blood stream of patients do not cause thrombosis or infection,or that biosensors do not lose their function due to adverse interactions with the bio environment.A general approach to the design of biointerfaces that addresses this need has been pursued over a number of years[1].It has two elements:(1)prevention of non-specific interfacial interactions,and(2)promotion of specific biointeractions required for the intended functioning of the *** practice this means preventing all interactions except for the desired one(s).With respect to the first point it should be appreciated that biological species such as proteins and cells have a natural affinity for the interfacial ***,the realization of a surface that eliminates the adsorption/adhesion of these species is extremely *** of PEO/PEG,other hydrophilic polymers(PVP,PHEMA),and zwitterionic polymers[2]to the surface is the most common strategy to achieve“bio-resistance”.Regarding the second point,the surface must be designed so that it interacts selectively and exclusively with the component(s)(proteins,cells)that will give the desired *** this purpose,“ligands”that bind these specific components are incorporated into the surface[3].

关键词： desired interfacial realization

Ionic conductivity anomaly in soil cover——Exploration of blind mineralization beneath regolith cover

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Science China Earth Sciences 2010年第5期53卷 649-656页

作者： KEElING john l. Primary Industries and Resources South Australia (PIRSA)

This paper briefly describes the formation of ionic conductivity anomalies in soil cover, and the characteristics of ionic composition that forms conductivity anomalies, based on the theory of geoelectrochemical halo. Based on some practical results of soluble ions in soil cover and soil conductivity derived from a number of mining areas of both China and overseas, here we present the correlation of a conductivity anomaly with the ionic composition and establish a model for the formation of conductivity anomalies in soil cover. The results indicate that the formation of a conductivity anomaly is not a simple transformation of a secondary geochemical anomaly. A conductivity anomaly is formed as the result of electrochemical and chemical processes, by transformation of orebody into various ionic haloes through four physicochemical processes: 1) dissolution of the orebody, 2) migration of dissolved matter, 3) conversion of matter near the surface, and 4) the formation of ionic conductivity anomalies. The conductivity anomaly, as a physical parameter, essentially represents the integration of various geochemical compositions and is controlled by a set of particular ionic groups.

关键词： ionic conductivity regolith mineralisation exploration

Synthesis of liSm_(0.01)Mn_(1.99)O_4 by molten salt technique

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Journal of Rare Earths 2010年第2期28卷 255-259页

作者： M Helan l john Berchmans Department of Chemistry Jamal Mohamed College (Autonomous) Electropyrometallurgy Division Central Electrochemical Research Institute

Samarium substituted lithium manganese oxide powders were successfully prepared by molten-salt synthesis(MSS) using eutectic mixture of liCl,SmCl3.6H2O and MnO2 salt at 700 °*** synthesis was carried out in open *** crystalline powders were characterized for their phase identification using X-ray diffraction(XRD) *** physico-chemical properties of the samarium substituted lithium manganese oxide powders were investigated by thermal analysis(TGA/DTA),FT-IR spectroscopy,EDAX,electron par...

关键词： liSm0.01Mn1.99O4 molten salt synthesis cathode materials rare earth ion

Mechanisms, prevention and clinical implications of nonsteroidal anti-inflammatory drug-enteropathy

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World Journal of Gastroenterology 2013年第12期19卷 1861-1876页

作者： john l Wallace Farncombe Family Digestive Health Research Institute McMaster University Inflammation Research Network University of Calgary

This article reviews the latest developments in understanding the pathogenesis, detection and treatment of small intestinal damage and bleeding caused by nonsteroidal anti-inflammatory drugs (NSAIDs). With improvements in the detection of NSAID-induced damage in the small intestine, it is now clear that this injury and the associated bleeding occurs more frequently than that occurring in the stomach and duodenum, and can also be regarded as more dangerous. However, there are no proven-effective therapies for NSAID-enteropathy, and detection remains a challenge, particularly because of the poor correlation between tissue injury and symptoms. Moreover, recent studies suggest that commonly used drugs for protecting the upper gastrointestinal tract (i.e., proton pump inhibitors) can significantly worsen NSAID-induced damage in the small intestine. The pathogenesis of NSAID-enteropathy is complex, but studies in animal models are shedding light on the key factors that contribute to ulceration and bleeding, and are providing clues to the development of effective therapies and prevention strategies. Novel NSAIDs that do not cause small intestinal damage in animal models offer hope for a solution to this serious adverse effect of one of the most widely used classes of drugs.

关键词： Anti-inflammatory Ulcer Prostaglandin Non-steroidal Bleeding Intestinal Bile Enterohepatic Bacteria Hydrogen sulfide Aspirin Hemorrhage

Configuration-Sensitive Molecular Sensing on Doped Graphene Sheets

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Nano Research 2010年第7期3卷 472-480页

作者： john Russell Petr Král Department of Chemistry University of Illinois at ChicagoChicagoIL 60607USA

We show by molecular dynamics simulations that configuration-sensitive molecular spectroscopy can be realized on optimally doped graphene sheets vibrated by an oscillatory electric *** selectivity of the spectroscopy is achieved by maximizing Coulombic binding between the detected molecule and a specific nest,formed for this molecule on the graphene sheet by substituting selected carbon atoms with boron and nitrogen *** can detect binding of different isomers to the nest from the frequency shifts of selected vibrational modes of the combined *** an illustrative example,we simulate detection of hexanitrostilbene enantiomers in chiral nests formed on graphene.

关键词： Molecular sensing enantiomer graphene functionalization molecular dynamics

Integration of the Coupled Orbit-Attitude Dynamics Using Modified Chebyshev-Picard Iteration Methods

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Computer Modeling in Engineering & Sciences 2016年第2期111卷 129-146页

作者： Xiaoli Bai john l.Junkins Rutgers The State University of New JerseyPiscatawayNJU.S.A Texas A&M College StationTXU.S.A

This paper presents Modified Chebyshev-Picard Iteration(MCPI)methods for long-term integration of the coupled orbit and attitude *** most orbit predictions for operational satellites have assumed that the attitude dynamics is decoupled from the orbit dynamics,the fully coupled dynamics is required for the solutions of uncontrolled space debris and space objects with high area-to-mass ratio,for which cross sectional area is constantly changing leading to significant change on the solar radiation pressure and atmospheric *** is a set of methods for solution of initial value problems and boundary value *** methods refine an orthogonal function approximation of long-time-interval segments of state trajectories iteratively by fusing Chebyshev polynomials with the classical Picard iteration and have been applied to multiple challenging aerospace *** the studies on integrating a torque-free rigid body rotation and a long-term integration of the coupled orbit-attitude dynamics through the effect of solar radiation pressure,MCPI methods are shown to achieve several times speedup over the Runge-Kutta 7(8)methods with several orders of magnitudes of better *** methods are further optimized by integrating the decoupled dynamics at the beginning of the iteration and coupling the full dynamics when the attitude solutions and orbit solutions are converging during the *** approach of decoupling and then coupling during iterations provides a unique and promising perspective on the way to warm start the solution process for the longterm integration of the coupled orbit-attitude ***,an attractive feature of MCPI in maintaining the unity constraint for the integration of quaternions within machine accuracy is illustrated to be very appealing.

关键词： Orbit propagation orbit-attitude dynamics Modified Chebyshev-Picard Iteration(MCPI)Methods

ANAlYSIS OF COMPOSITE lAMINATE BEAMS USING COUPlING CROSS-SECTION FINITE ElEMENT METHOD

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Applied Mathematics and Mechanics(English Edition) 2006年第12期27卷 1709-1718页

作者：姜文光 john l.Henshall School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004Hebei ProvinceP. R. China Department of Aerospace Engineering University of BristolBS8 1TRUK Department of Mechanical Engineering and Manufacturing Engineering Nottingham Trent UniversityNottinghamNG1 4BUUK

Beams and plates manufactured from laminates of composite materials have distinct advantages in a significant number of applications. However, the anisotropy arising from these materials adds a significant degree of complexity, and thus time, to the stress and deformation analyses of such components, even using numerical approaches such as finite elements. The analysis of composite laminate beams subjected to uniform extension, bending, and/or twisting loads was performed by a novel implementation of the usual finite element method. Due to the symmetric features of the deformations, only a thin slice of the beam to be analysed needs to be modelled. Conventional threedimensional solid finite elements were used for the structural discretization. The accurate deformation relationships were formulated and implemented through the coupling of nodal translational degrees of freedom in the numerical analysis. A sample solution for a rectangular composite laminate beam is presented to show the validity and accuracy of the proposed method.

关键词： composite material beam coupling equation finite element method extension bending torsion

Effects of hydraulic retention time, temperature, and effluent recycling on efficiency of anaerobic filter in treating rural domestic wastewater

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Water Science and Engineering 2014年第2期7卷 168-182页

作者： john leju Celestino lADU Xi-wu lü School of Energy and Environment Southeast University College of Natural Resources and Environmental Studies University of Juba

With rural population expansion and improvement of the socio-economic standard of living, treatment of rural domestic wastewater has rapidly become a major aspect of environmental concern. Selection of a suitable method for treatment of rural domestic wastewater depends on its efficiency, simplicity, and cost-effectiveness. This study investigated the effects of hydraulic retention time （HRT）, temperature, and effluent recycling on the treatment efficiency of an anaerobic filter （AF） reactor. The first round of experimental operations was run for three months with HRTs of one, two, and three days, temperatures of 18℃, 21℃, and 24℃, and no effluent recycling. The second round of experimental operations was conducted for another three months with HRTs of three and four days; temperatures of 30.67℃, 30.57℃, and 26.91 ℃ ; and three effluent recycling ratios of 1：1, 1：2, and 2：1. The first round of operations showed removal rates of 32% to 44% for COD, 30% to 35% for TN, 32% to 36% for NH4-N, 19% to 23% for NO3-N, and 12% to 22% for TE In the second round of operations, the removal rates varied from 75% to 81% for COD, 35% to 41% for TN, 31% to 39% for NH4-N, 30% to 34% for NO3-N, and 41% to 48% for TP. The average gas production rates were 6.72 l/d and 7.26 l/d for the first and second rounds of operations, respectively. The gas production rate increased in the second round of operations as a result of applied effluent recycling. The best removal efficiency was obtained for an optimum HRT of three days, a temperature of 30℃, and an effluent recycling ratio of 2：1. The results show that the removal efficiency of the AF reactor was affected by HRT, temperature, and effluent recycling.

关键词： anaerobic filter (AF) rural domestic wastewater hydraulic retention time (HRT) effluent recycling experimental operation