检索结果-南通市图书馆

World Journal of gastroenterology 2003年第12期9卷 2681-2685页

作者： Andreas geier Carsten gartung christoph g.dietrich Hermann E.Wasmuth Patrick Reinartz Siegfried Matern Department of Intemal Medicine Ⅲ University of Technology (RWTH) AachenAachenGermany Nuclear Medicine University of Technology (RWTH) AachenAachenGermany Department of Internal Medicine Ⅲ University of Technology (RWTH) AachenAachenGermany

AIM: To investigate the systemic availability of budesonide in a patient with Child A drrhosis due to autoimmune hepatitis (AIH) and primary hepatocellular carcinoma, who developed serious side ***: Serum levels of budesonide, 6β-OH-budesonide and 16α-OH-prednisolon were measured by HPLC/MS/MS;portosysternic shunt-index (SI) was determined by 99mTc nuclear imaging. All values were compared with a matched control patient without side ***: Serum levels of budesonide were 13-fold increased in the index patient. The ratio between serum levels of the metabolites 6β-OH-budesonide and 16α-OH-prednisolone, respectively, and serum levels of budesonide was diminished (1.0 vs. 4.0 for 6β-OH-budesonide, 4.2 vs.10.7 for 16α-OH-prednisolone). Both patients had portosystemic SI (5.7% and 3.1%) within the range of healthy ***: Serum levels of budesonide vary up to 13-fold in AIH patients with Child A cirrhosis in the absence of relevant portosysternic shunting. Reduced hepatic metabolism, as indicated by reduced metabolite-to-drug ratio, rather than portosystemic shunting may explain systemic side effects of this drug in cirrhosis.

关键词：布地缩松副作用肝硬化慢性自身免疫性肝炎门静脉吻合术丙型肝炎合并症

Multiple sclerosis drug repurposing for neuroregeneration

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2024年第3期19卷 507-508页

作者： Peter göttle Michael dietrich Patrick Küry Department of Neurology Medical FacultyHeinrich-Heine UniversityDüsseldorfGermany

Multiple sclerosis(MS)is an autoimmune disorder of the central nervous system(CNS)and is primarily characterized by immune cell infiltration leading to relapses followed by remission phases and a disease course turning progressive over time with neurodegenerative processes taking over(Amin and Hersh,2023).Of note,beyond relapse-associated worsening early in disease progression independent of relapse activity may arise independently of relapse activity and can occur in all ***-mediated damage of myelin sheaths and the subsequent loss of mature oligodendrocytes are resulting in impaired axonal integrity,neurodegeneration and accounts for irreversible neuronal damage(Kuhlmann et al.,2023).The current landscape of available disease-modifying therapies comprises mainly immunomodulatory drugs that effectively diminish relapses and slow down progression at the onset form of the disease,namely relapsing MS(RMS).In this regard,a number of drugs have been approved as disease-modifying therapies for MS by US Food and Drug Administration and European Medicines Agencies(Box 1).

关键词： drugs impaired irreversible

Occult celiac disease prevents penetrance of hemochromatosis

在线全文

学校读者我要写书评

暂无评论

World Journal of gastroenterology 2005年第21期11卷 3323-3326页

作者： Andreas geier Carsten gartung Igor Theurl guenter Weiss Frank Lammert christoph g.dietrich Ralf Weiskirchen Heinz Zoller Benita Hermanns Siegfried Matern Department of Internal Medicine Ⅲ Aachen University (RWTH) AachenGermany Department of Internal Medicine University of Innsbruck InnsbruckAustria Department of Clinical Chemistry and Pathobiochemistry Aachen University(RWTH) AachenGermany Department of Pathology Aachen University (RWTH) AachenGermany Department of Internal Medicine Ⅲ Aachen University(RWTH) Aachen Germany

AIM: To report a patient with C282Y homozygocity, depleted body iron and intestinal atrophy caused by celiac disease (CD) who experienced resolution of the enteropathy with subsequent normalization of iron metabolism upon glutenfree ***: To obtain information on the tissue distribution and quantitative expression of proteins involved in duodenal iron trafficking, we determined the expression of divalent-metal transporter 1 (DMT1), ferroportin 1 (FP1) and transferrin receptor (TfR1) by means of immunohistochemistry and real-time PCR in duodenal biopsies of this ***: Whereas in hereditary hemochromatosis patients without CD, DMT1 expression was up-regulated leading to excessive uptake of iron, we identified a significant reduction in protein and mRNA expression of DMT1 as acompensatory mechanism in this patient with HH and ***: Occult CD may compensate tot increased DMT1 expression in a specific subset of individuals withhomozygous C282Y mutations in the hemochromatosis(HFE) gene, thus contributing to the low penetrance of HH.

关键词：腹腔疾病血色沉着病外显率疾病预防 C282Y 肠萎缩

Energy enhancement of laser-driven ions by radiation reaction and Breit-Wheeler pair production in the ultra-relativistic transparency regime

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

High Power Laser Science and Engineering 2024年第1期12卷 60-73页

作者： Shikha Bhadoria Mattias Marklund christoph H.Keitel Max-Planck-Institut für Kernphysik HeidelbergGermany Department of Physics University of GothenburgGöteborgSweden

The impact of radiation reaction and Breit±Wheeler pair production on the acceleration of fully ionized carbon ions driven by an intense linearly polarized laser pulse has been investigated in the ultra-relativistic transparency *** initial expectations, the radiation reaction and pair production at ultra-high laser intensities are found to enhance the energy gained by the ions. The electrons lose most of their transverse momentum, and the additionally produced pair plasma of Breit±Wheeler electrons and positrons co-streams in the forward direction as opposed to the existing electrons streaming at an angle above zero degree. We discuss how these observations could be explained by the changes in the phase velocity of the Buneman instability, which is known to aid ion acceleration in the breakout afterburner regime, by tapping the free energy in the relative electron and ion streams. We present evidence that these non-classical effects can further improve the highest carbon ion energies in this transparency regime.

关键词： ion acceleration quantum electrodynamic effects

Implementation and validation of a bonded particle model to predict rheological properties of viscoelastic materials

在线全文

学校读者我要写书评

暂无评论

Particuology 2024年第6期89卷 198-210页

作者： Michael Mascara Arno Mayrhofer Stefan Radl christoph Kloss Institute of Process and Particle Engineering Graz University of TechnologyInffeldgasse 13Graz8010Austria DCS Computing gmbH Industriezeile 35Linz4020Austria

This work focuses on implementing a particle-based method able to characterize viscoelastic materials whose rheological properties,such as storage modulus g′and loss modulus g″,are *** is based on the bonded particle model,with the elastic constitutive relation here substituted with a viscoelastic one to capture time-scale *** Burgers model,vastly used in literature to model viscoelastic systems,is discretized and *** test case used for calibration comprises of a cubic lattice,sheared with a periodic motion,to mimic the effect of a shear *** appropriate filtering of the stress response,the rheological properties are obtained,highlighting the effect of the lattice geometry,as well as the particle size,on the accuracy of the ***,the Burgers parameters are calibrated by analytically fitting the experimental dataset,showing the limitation of the Burgers *** micro-contact parameters are obtained from the macro parameters through appropriate *** completing a frequency sweep,the simulated g′and g″show a relatively large error,around 25%for g’for *** this reason,a more robust model,namely the generalized Maxwell model,has been *** calibration procedure is performed in the same fashion as for the Burgers ***,the tangential micro-contact parameters are scaled *** normal *** scaling parameter,calledα,is calibrated by minimizing the root mean square error between simulation and experimental data,giving errors below 10%in both g′and g″for a large ***,a full ring plate-plate rheometer setup is simulated,and the simulation is compared with the given experimental dataset,again finding a good agreement.

关键词： DEM Rheology Numerical modeling Viscoelasticity

Recycled graphite for more sustainable lithium-ion batteries

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Carbon Energy 2024年第5期6卷 15-24页

作者： Mayokun Olutogun Anna Vanderbruggen christoph Frey Martin Rudolph Dominic Bresser Stefano Passerini Helmholtz Institute Ulm(HIU) Ulm germany Karlsruhe Institute of Technology(KIT) KarlsruheGermany Helmholtz Zentrum Dresden-Rossendorf(HZDR) Helmholtz Institute Freiberg for Resource Technology(HIF)FreibergGermany Prographite gmbH UntergriesbachGermany Chemistry Department Sapienza University of RomeRomeItaly

The demand for lithium-ion batteries(LIBs)is driven largely by their use in electric vehicles,which is projected to increase dramatically in the *** great success,however,urgently calls for the efficient recycling of LIBs at the end of their ***,we describe a froth flotation-based process to recycle graphite—the predominant active material for the negative electrode—from spent LIBs and investigate its reuse in newly assembled *** has been found that the structure and morphology of the recycled graphite are essentially unchanged compared to pristine commercial anode-grade graphite,and despite some minor impurities from the recycling process,the recycled graphite provides a remarkable reversible specific capacity of more than 350 mAh g^(−1).Even more importantly,newly assembled graphite‖NMC532 cells show excellent cycling stability with a capacity retention of 80%after 1000 cycles,that is,comparable to the performance of reference full cells comprising pristine commercial graphite.

关键词： anode graphite lithium-ion battery recycling sustainability

Towards engineering a portable platform for laparoscopic pre-training in virtual reality with haptic feedback

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

虚拟现实与智能硬件（中英文） 2024年第2期6卷 83-99页

作者： Hans-georg ENKLER Wolfgang KUNERT Stefan PFEFFER Kai-Jonas BOCK Steffen AXT Jonas JOHANNINK christoph REICH Furtwangen University 78120 FurtwangenGermany University Hospital and Faculty of Medicine Tuebingen 72076 TuebingenGermany

Background Laparoscopic surgery is a surgical technique in which special instruments are inserted through small incision holes inside the *** some time,efforts have been made to improve surgical pre training through practical exercises on abstracted and reduced *** The authors strive for a portable,easy to use and cost-effective Virtual Reality-based(VR)laparoscopic pre-training platform and therefore address the question of how such a system has to be designed to achieve the quality of today's gold standard using real tissue *** VR controllers are limited regarding haptic *** haptic feedback is necessary or at least beneficial for laparoscopic surgery training,the platform to be developed consists of a newly designed prototype laparoscopic VR controller with haptic feedback,a commercially available head-mounted display,a VR environment for simulating a laparoscopic surgery,and a training *** To take full advantage of benefits such as repeatability and cost-effectiveness of VR-based training,the system shall not require a tissue sample for haptic *** is currently calculated and visually displayed to the user in the VR *** the prototype controller,a first axis was provided with perceptible feedback for test *** of the prototype VR controllers can be combined to simulate a typical both-handed use case,e.g.,laparoscopic suturing.A Unity based VR prototype allows the execution of simple standard *** The first prototype enables full operation of a virtual laparoscopic instrument in *** addition,the simulation can compute simple interaction *** challenges lie in a realistic real-time tissue simulation and calculation of forces for the haptic *** weaknesses were identified in the first hardware prototype,which will be improved in subsequent *** degrees of freedom of the controller are to be provided with haptic *** make forces t

关键词： Laparoscopic surgery Training Virtual reality Controller Haptic feedback Kinesthetic skills

Challenges and opportunities in the production of magnesium parts by directed energy deposition processes

在线全文

学校读者我要写书评

暂无评论

Journal of Magnesium and Alloys 2024年第5期12卷 1663-1686页

作者： gürel Cama Ali günen Iskenderun Technical University Faculty of Engineering and Natural SciencesDepartment of Mechanical Engineering31200˙Iskenderun-HatayTurkey Iskenderun Technical University Faculty of Engineering and Natural SciencesDepartment of Metallurgy and Materials Engineering31200 Iskenderun-HatayTurkey

Mg-alloys have gained considerable attention in recent years for their outstanding properties such as lightweight,high specific strength,and corrosion resistance,making them attractive for applications in medical,aerospace,automotive,and other transport ***,their widespread application is hindered by their low formability at room temperature due to limited slip *** Mg-alloys have low mechanical properties due to the presence of casting defects such as porosity and anisotropy in addition to the high *** casting methods benefit from established process optimization techniques for these problems,additive manufacturing methods are increasingly replacing casting methods in Mg alloys as they provide more precise control over the microstructure and allow specific grain orientations,potentially enabling easier optimization of anisotropy properties in certain *** metal additive manufacturing(MAM)technology also results in some manufacturing defects such as inhomogeneous microstructural evolution and porosity and additively manufactured Mg alloy parts exhibit lower properties than the wrought parts,they in general exhibit superior properties than the cast ***,MAM is a promising technique to produce Mg alloy *** energy deposition processes,particularly wire arc directed energy deposition(WA-DED),have emerged as an advantageous additive manufacturing(AM)technique for metallic materials including magnesium alloys,offering advantages such as high deposition rates,improved material efficiency,and reduced production costs compared to subtractive ***,the inherent challenges associated with magnesium,such as its high reactivity and susceptibility to oxidation,pose unique hurdles in the application of this *** review paper delves into the progress made in the application of DED technology to Mg-alloys,its challenges,and ***,the predominant imperfections,notably inhomo

关键词： Additive manufacturing DED processes Arc-DED Wire arc additive manufacturing(WAAM) 3-D printing High deposition rate

Recent research in mechanical properties of geopolymer-based ultrahigh-performance concrete:A review

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第2期32卷 67-88页

作者： g.Murali Division of Research&Innovation Uttaranchal UniversityDehradun 248007India

Due to the growing need for sustainable and ultra-high-strength construction materials,scientists have created an innovative ultra-high-performance concrete called geopolymer based ultra-highperformance concrete(gUHPC).Besides,in the last few decades,there have been a lot of explosions and ballistic attacks around the world,which have killed many civilians and fighters in border *** this context,this article reviews the fresh state and mechanical properties of ***,the ingredients of gUHPC and fresh properties such as setting time and flowability are briefly ***,the review of compressive strength,flexure strength,tensile strength and modulus of elasticity of fibrous ***,the blast and projectile impact resistance performance was ***,the microstructural characteristics were reviewed using the scanning electron microscope and X-ray Powder *** review outcome reveals that the mechanical properties were increased when 30%silica fume was added to a higher dose of steel fibre to improve the microstructure of *** is hypothesized that the brittleness of gUHPC was mitigated by adding 1.5%steel fibre reinforcement,which played a role in the decrease of contact explosion cratering and *** the need for cement in gUHPC was a key factor in the review,indicating a promising potential for lowering carbon ***,gUHPC research is still in its early stages,so more study is required before its full potential can be utilized.

关键词： Mechanical properties Blast Projectile impact Fibre geopolymer Silica fume Alkaline activators

Non-alcoholic fatty liver disease and COVID-19: Harmless companions or disease intensifier?

在线全文

学校读者我要写书评

暂无评论

World Journal of gastroenterology 2023年第2期29卷 367-377页

作者： christoph g.dietrich Andreas geier Uta Merle gastro-Praxis Wiesbaden Leberzentrum WiesbadenWiesbaden 65189Germany Division of Hepatology Department of Medicine IIUniversity Hospital WuerzburgWuerzburg 97080Germany Department of gastroenterology and Hepatology University Hospital HeidelbergHeidelberg 69120Germany

The pandemics of coronavirus disease 2019(COVID-19)and non-alcoholic fatty liver disease(NAFLD)*** liver function tests are frequent in COVID-19 and may influence liver damage in NAFLD,while preexisting liver damage from NAFLD may influence the course of ***,the prognostic relevance of this interaction,though,is *** is a risk factor for the presence of NAFLD as well as a severe course of *** studies reveal conflicting results regarding the influence of NAFLD presence on COVID-19 illness *** molecular similarities of cytokine pathways in both diseases,including postacute sequelae of COVID-19,suggest common pathways for chronic low-activity *** review will summarize existing data regarding the interaction of both diseases and discuss possible mechanisms of the influence of one disease on the other.

关键词： COVID-19 Postacute sequelae of COVID-19 Non-alcoholic fatty liver disease Non-alcoholic steatohepatitis Inflammation Fatty liver