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Evidence-based management of gastrointestinal diseases

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Gastroenterology Report 2015年第1期3卷 1-2页

作者： j.thomas Lamont Division of Gastroenterology Beth Israel Deaconess Medical CenterHarvard Medical SchoolDA-501330 Brookline AvenueBostonMA 02215USA

This special issue of Gastroenterology Report is directed at“Evidence-based management of gastrointestinal(GI)diseases”.Gastroenterologists are now using a range of diagnostic tests and therapies that were largely unavailable twenty years *** is a fast-moving field,with innovations being developed at a rapid *** in this issue are authoritative reviews on how to manage a wide variety of conditions that affect the GI and biliary tracts using both established and emerging technologies,with emphasis on evidence to support the best practices and to achieve the best possible outcomes for our patients;for example,much has changed as regards our diagnostic accuracy in celiac disease.

关键词： diseases gastrointestinal patients

The six-question Gastroesophageal Reflux Disease Questionnaire(GerdQ)cannot accurately quantify reflux and reflux-associated symptoms frequency

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Gastroenterology Report 2022年第1期10卷 683-684页

作者： thomas j.Hurr South Australian Reflux Research Unit AdelaideSouth AustraliaAustralia

The aim of this commentary is to demonstrate,using two examples,that the six-question Gastroesophageal Reflux Disease Questionnaire(GerdQ)cannot accurately quantify reflux and reflux-associated symptoms(RRAS)frequency... 详细信息

关键词： symptoms oesophageal Gerd

High Oxygen Nanocomposite Barrier Films Based on Xylan and Nanocrystalline Cellulose

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Nano-Micro Letters 2010年第4期2卷 235-241页

作者： Amit Saxena thomas j.Elder jeffrey Kenvin Arthur j.Ragauskas School of Chemistry and Biochemistry Georgia Institute of Technology USDA-Forest Service Southern Research Station Micromeritics Instrument Corporation

The goal of this work is to produce nanocomposite film with low oxygen permeability by casting an aqueous solution containing xylan,sorbitol and nanocrystalline *** morphology of the resulting nanocomposite films was examined by scanning electron microscopy and atomic force microscopy which showed that control films containing xylan and sorbitol had a more open structure as compared to xylan-sorbitol films containing sulfonated nanocrystalline *** average pore diameter,bulk density,porosity and tortuosity factor measurements of control xylan films and nanocomposite xylan films were examined by mercury intrusion porosimetry *** films reinforced with nanocrystalline cellulose were denser and exhibited higher tortuosity factor than the control xylan *** xylan films had average pore diameter,bulk density,porosity and tortuosity factor of 0.1730 μm,0.6165 g/ml,53.0161% and 1.258,respectively as compared to xylan films reinforced with 50% nanocrystalline cellulose with average pore diameter of 0.0581 μm,bulk density of 1.1513 g/ml,porosity of 22.8906% and tortuosity factor of *** transmission rate tests demonstrated that films prepared with xylan,sorbitol and 5%,10%,25% and 50% sulfonated nanocrystalline cellulose exhibited a significantly reduced oxygen permeability of 1.1387,1.0933,0.8986 and 0.1799 cm^3×μm/m^2×d×k Pa respectively with respect to films prepared solely from xylan and sorbitol with a oxygen permeability of 189.1665 cm^3×μm/m^2×d×k *** properties suggested these nanocomposite films have promising barrier properties.

关键词： Nanocomposites Xylan Nanocrystalline cellulose Oxygen barrier

Isotretinoin for the treatment of nonobstructive azoospermia: a pilot study

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Asian journal of Andrology 2021年第5期23卷 537-540页

作者： john K Amory Charles H Muller thomas j Walsh Department of Medicine University of WashingtonSeattleWA 98195USA Department of Urology University of WashingtonSeattleWA 98195USA

The treatment of men with infertility from azoospermia is *** some men with severe oligozoospermia improve sperm output during treatment with isotretinoin,we treated nine men with azoospermia with isotretinoin to determine if azoospermic men would also respond to isotretinoin *** of these men who had a previous negative testicular sperm extraction(TESE)was found to have an area of sperm production on a postisotretinoin testicular *** man achieved a pregnancy and a live birth of a healthy,term daughter after in vitro fertilization coupled with intracytoplasmic sperm injection(IVF/ICSI).A second subject had a positive TESE after treatment as *** study of isotretinoin therapy in men with azoospermia undergoing testicular sperm harvesting procedures is warranted.

关键词： treatment injection pregnancy

Can inhibition of telomerase increase pancreatic cancer cell's susceptibility to chemotherapeutic reagents?

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Hepatobiliary & Pancreatic Diseases International 2002年第1期1卷 155-160页

作者： thomas j.Ⅲ Fahey Department of Surgery Cornell University Medical College New York NY USA

Objectives: To clarify the inhibition of pancreatic can-cer cells by interference with the hTR component of thetelomerase reverse transcriptase enzymatic complexand evaluate susceptibility of antisense hTR pancreaticcancer cells to chemotherapeutic ***: A 593 bp of full length hTR cDNA was sub-cloned into a mammalian expression vector pcDNA3.1(-) in antisense orientation to construct an antisensehTR expression plasmid. The plasmids were introducedinto Pancl cells, a human pancreatic carcinoma cellline, by lipofectin, and G418-resistant stable trans-formants were expanded. Resulting stable clones werescreened for the presence of hTR insert by PCR withT7 and BGH reverse primers located on the flanks ofthe multiclonal site of pcDNA3.1 vector. Cell growth rate,hTR expression, telomerase activity, and anchorage-in-dependent growth property were analyzed. Finally, sus-ceptibility of antisense hTR cells to chemotherapeuticreagents was ***: Significant downregulation of endogenous hTRwas evident in the antisense-hTR transformed cells,and telomerase activity was markedly decreased com-pared to control cells in standard TRAP assays. Fur-thermore, the proliferation and the anchorage-inde-pendent growth ability in antisense-hTR expressingcells were significantly decreased compared with thecontrol parental cells. However, no crisis or senescencephenomena was observed. Antisense hTR appears toincrease Pancl cell's susceptibility to chemotherapeuticreagent cDDP, but not to differentiation reagent DM-SO, COX2 inhibitor sulinbac, NS-398, curcumin, andchemotherapeutic reagent adriamycin(ADM).Conclusions: These data indicate that hTR is probablya critical component of human telomerase activity andthat downregulation of the RNA component of humantelomerase is an effective target for anticancer strategyand antisense hTR can increase Pancl cell's susceptibilityto cDDP.

关键词： Telomerase hTR Antisense Pancreatic carcinoma cellline chemotherapeutic reagents

Multiscale Domain Decomposition Methods for Elliptic Problems with High Aspect Ratios

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Acta Mathematicae Applicatae Sinica 2002年第1期18卷 63-76页

作者： jφrgAarnes thomas Y.Hou Department of Mathematics University of BergenJohs.Brunsgt.125008 BergenNorwayApplied Mathematics217-50CaltechPasadenaCA 91125

In this paper we study some nonoverlapping domain decomposition methods for solving a class of elliptic problems arising from composite materials and flows in porous media which contain many spatial scales. Our preconditioner differs from traditional domain decomposition preconditioners by using a coarse solver which is adaptive to small scale heterogeneous features. While the convergence rate of traditional domain decomposition algorithms using coarse solvers based on linear or polynomial interpolations may deteriorate in the presence of rapid small scale oscillations or high aspect ratios, our preconditioner is applicable to multiple-scale problems without restrictive assumptions and seems to have a convergence rate nearly independent of the aspect ratio within the substructures. A rigorous convergence analysis based on the Schwarz framework is carried out, and we demonstrate the efficiency and robustness of the proposed preconditioner through numerical experiments which include problems with multiple-scale coefficients, as well problems with continuous scales.

关键词： Multiscale elliptic problems Domain decomposition Schwarz methods Porous media

Recent Increased Warming of the Alaskan Marine Arctic Due to Midlatitude Linkages

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Advances in Atmospheric Sciences 2018年第1期35卷 75-84页

作者： james E.OVERLAND Muyin WANG thomas j.BALLINGER NOAA/Pacific Marine Environmental Laboratory Seattle WA 98115USA joint Institute for the Study of Atmosphere and Oceans University of Washington Seattle WA 98115USA Department of Geography Texas State UniversitySan Marcos TX 78666USA

Alaskan Arctic waters have participated in hemispheric-wide Arctic warming over the last two decades at over two times the rate of global warming. During 2008–13, this relative warming occurred only north of the Bering Strait and the atmospheric Arctic front that forms a north–south thermal barrier. This front separates the southeastern Bering Sea temperatures from Arctic air masses. Model projections show that future temperatures in the Chukchi and Beaufort seas continue to warm at a rate greater than the global rate, reaching a change of +4℃ by 2040 relative to the 1981–2010 mean. Offshore at 74°N, climate models project the open water duration season to increase from a current average of three months to five months by 2040. These rates are occasionally enhanced by midlatitude connections. Beginning in August 2014, additional Arctic warming was initiated due to increased SST anomalies in the North Pacific and associated shifts to southerly winds over Alaska, especially in winter 2015–16. While global warming and equatorial teleconnections are implicated in North Pacific SSTs, the ending of the 2014–16 North Pacific warm event demonstrates the importance of internal, chaotic atmospheric natural variability on weather conditions in any given year. Impacts from global warming on Alaskan Arctic temperature increases and sea-ice and snow loss, with occasional North Pacific support, are projected to continue to propagate through the marine ecosystem in the foreseeable future. The ecological and societal consequences of such changes show a radical departure from the current Arctic environment.

关键词： Alaska North Pacific Arctic warm advection polar vortex

Particle flow simulations with homogenised lattice Boltzmann methods

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Particuology 2017年第5期15卷 1-13页

作者： Mathias j. Krause Fabian Klemens thomas Henn Robin Trunk Hermann Nirschl Institute for Applied and Numerical Mathematics Karlsruhe Institute of Technology 76021 Karlsruhe Germany Institute for Mechanical Process Engineering and Mechanics Karlsruhe Institute of Technology 76021 Karlsruhe Germany

An alternative approach to simulating arbitrarily shaped particles submersed in viscous fluid in two dimensions is proposed, obtained by adapting the velocity parameter of the equilibrium distribution function of a standard lattice Boltzmann method （LBM）. Comparisons of exemplifying simulations to results in the literature validate the approach as well as the convergence analysis. Pressure fluctuations occurring in Ladd＇s approach are greatly reduced. In comparison with the immersed boundary method, this approach does not require cost intensive interpolations. The parallel efficiency of LBM is retained. An intrinsic momentum transfer is observed during particle-particle collisions. To demonstrate the capa- bilities of the approach, sedimentation of particles of several shapes is simulated despite omitting an explicit particle collision model.

关键词： Particulate flow simulationsArbitrarily shaped particlesLattice Boltzmann methodsValidationSedimentation processes

Microbial roles equivalent to geological agents of high temperature and pressure in deep Earth

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Science China Earth Sciences 2016年第11期59卷 2098-2104页

作者： XIE ShuCheng LIU Deng QIU Xuan HUANG XianYu thomas j.ALGEO State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences Laboratory of Critical Zone Evolution School of Earth Sciences China University of Geosciences State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Department of Geology University of Cincinnati

Microbes not only show sensitive responses to environmental changes but also play important roles in geochemical and geophysical systems. It is well known that microbes have caused major changes in surface environments and biogeochemical cycles through Earth history. Microbial processes can also induce the synthesis of certain minerals under Earth-surface conditions that previously were believed to form only under high temperatures and pressures in the deep Earth. For example, microbes can promote the conversion of smectite to illite, synthesis of authigenic plagioclase, precipitation of dolomite, and biotransformation of geolipids. These effects of microbes are due to their large surface/volume ratios, enzyme production, and abundant functional groups. Microbial catalyzation of chemical reactions proceeds through reaction-specific enzymes, a decrease in Gibbs' s free energy, and/or break through the dynamics reaction thresholds via their metabolisms and physiology. Microbes can lower the surface free energy of mineral nuclei via biophysical adsorption due to their large surface/volume ratios and abundant functional groups. The mineral precipitation and transformation processes induced by microbes are functionally equivalent to geological processes operating at high temperatures and pressures in the deep Earth, suggesting that microbial processes can serve as analogs to deep abiotic processes that are difficult to observe.

关键词： Geobiology Microbial functional groups Illitization Plagioclase Dolomite Geolipids