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Travelling Waves for a Density Dependent Diffusion Nagumo Equation over the Real Line

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Communications in Theoretical Physics 2012年第7期58卷 5-11页

作者： robert A. Van Gorder Department of mathematics University of Central FloridaP.O.Box 161364OrlandoFL 32816-1364USA

We consider the density dependent diffusion Nagumo equation, where the diffusion coefficient is a simple power function. This equation is used in modelling electrical pulse propagation in nerve axons and in population genetics (amongst other areas). In the present paper, the δ-expansion method is applied to a travelling wave reduction of the problem, so that we may obtain globally valid perturbation solutions (in the sense that the perturbation solutions are valid over the entire infinite domain, not just locally; hence the results are a generalization of the local solutions considered recently in the literature). The resulting boundary value problem is solved on the real line subject to conditions at z →±∞. Whenever a perturbative method is applied, it is important to discuss the accuracy and convergence properties of the resulting perturbation expansions. We compare our results with those of two different numerical methods (designed for initial and boundary value problems, respectively) and deduce that the perturbation expansions agree with the numerical results after a reasonable number of iterations. Finally, we are able to discuss the influence of the wave speed c and the asymptotic concentration value α on the obtained solutions. Upon recasting the density dependent diffusion Nagumo equation as a two-dimensional dynamical system, we are also able to discuss the influence of the nonlinear density dependence (which is governed by a power-law parameter m) on oscillations of the travelling wave solutions.

关键词： density dependent diffusion equation nonlinear partial differential equation perturbation method δ-expansion method

mycophenolate mofetil for drug-induced vanishing bile duct syndrome

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World Journal of Gastroenterology 2007年第45期13卷 6087-6089页

作者： S Simona Jakab A Brian West Dennis m meighan robert S Brown Jr William B Hale Section of Gastroenterology Norwalk Hospital Norwalk CT 06856United States Department of Pathology New York UniversityNew York NY United States Center for Liver Disease and Transplantation New York-Presbyterian Hospital Columbia University College of Physicians and Surgeons New York NY United States

Amoxicillin/clavulanate is associated with liver injury, mostly of a cholestatic pattern. While outcomes are usually benign, progression to cirrhosis and death has been reported. The role of immunosuppressive therapy for patients with a protracted course is unclear. We report the case of an elderly patient who developed prolonged cholestasis secondary to amoxicillin/clavulanate. Vanishing bile duct syndrome was confirmed by sequential liver biopsies. The patient responded to prednisone treatment, but could not be weaned off corticosteroids, even when azathioprine was added. Complete withdrawal of both prednisone and azathioprine was possible by using mycophenolate mofetil, an inosine monophosphate dehydrogenase inhibitor. Sustained remission has been maintained for more than 3 years with low-dose mycophenolate mofetil.

关键词： Amoxicillin and clavulanate Drug-inducedcholestasis Ductopenia mycophenolate mofetil Vanishingbile duct syndrome

Inhibition of sperm motility does not affect live-dead separation of bull sperm by glass beads

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Asian Journal of Andrology 2001年第3期3卷 193-198页

作者： robert H.Foote Department of Animal Science Cornell University Ithaca NY 14853-4801 USA

Aim: This study was designed to explore factors which influence binding of dead versus live sperm to glass ***: multiple semen collections from bulls were used to explore selective filtration of bull sperm as influencedby nonlethal inhibition of sperm motility with fluoride, killing of sperm by quick-freezing, alteration of the glass sur-face with silicone, and different intervals of sexual rest between semen collections. Results: A comparison of glassspheres 100, 200 and 390μm in diameter indicated that 200 μm spheres were optimal for selective filtration. Quantita-tive separation of live from dead sperm was demonstrated with a correlation between the percentage of motile sperm andretention of sperm by the filter of r = -0.87 (P mol/L NaFl did not alter the proportion ofsperm retained by the filter despite inhibiting sperm motility during filtration, an inhibition which was reversible. Pro-portions of live-dead sperm, based upon eosin staining, were unaffected by fluoride. Coating the glass spheres with sil-icone greatly reduced selective filtration. Dead sperm adherence to glass was reduced and resistance to NaFl inhibitionwas increased by daily ejaculation versus one-week intervals of sexual rest. Conclusion; These studies indicate thatthe adherence of sperm to glass is primarily due to some form of physico-chemical change accompanying death of thesperm cell independent of active sperm motility. This attraction between the sperm plasma membrane and glass is modi-fied by the age of the ejaculated sperm. This information is useful in evaluating different clinical procedures used forsperm separation. (Asian J Androl 2001 Sep; 3: 193-198)

关键词： sperm motility glass spere filters silicone fluorides inhibition

Current surgical treatments for Parkinson's disease and potential therapeutic targets

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Neural Regeneration Research 2018年第8期13卷 1342-1345页

作者： Darrin J.Lee robert F.Dallapiazza Philippe De Vloo Andres m.Lozano Division of Neurosurgery Toronto Western Hospital Department of Surgery University of Toronto

Currently, the most common surgical treatment for Parkinson＇s disease is deep brain stimulation（DBS）. This treatment strategy is typically reserved for bradykinesia, rigidity and tremor in patients who no longer respond to medication in a predictable manner or who suffer medication-induced dyskinesias. In addition to DBS, ablative procedures like radiofrequency, radiosurgery and focused ultrasound are also utilized for select tremor symptoms. In this review, we discuss evolving surgical techniques, targets, and emerging technology. In addition, we evaluate potential paradigm shifts in treatment, including gene therapy, immunotherapy and cell transplantation. While these new techniques and treatment options are still in their infancy, advances in Parkinson＇s disease treatment are rapidly expanding.

关键词： Parkinson's disease deep brain stimulation pallidotomy thalamotomy focused ultrasound gene therapy immunotherapy cell transplantation

Autoimmune gastritis:Pathologist's viewpoint

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World Journal of Gastroenterology 2015年第42期21卷 12179-12189页

作者： Irene Coati matteo Fassan Fabio Farinati David Y Graham robert m Genta massimo Rugge Department of medicine (DImED) Surgical Pathology Unit University of Padua Department of Surgery Oncology and Gastroenterology Gastroenterology Unit University of Padua Department of medicine Veterans Administration Hospital Baylor College of Medicine Houston miraca Life Sciences Research Institute Departments of Pathology and medicine VA North Texas Health Care System and University of Texas Southwestern Medical Center Dallas

Western countries are seeing a constant decline in the incidence of Helicobacter pylori-associated gastritis, coupled with a rising epidemiological and clinical impact of autoimmune gastritis. This latter gastropathy is due to autoimmune aggression targeting parietal cells through a complex interaction of auto-antibodies against the parietal cell proton pump and intrinsic factor, and sensitized T cells. Given the specific target of this aggression, autoimmune gastritis is typically restricted to the gastric corpus-fundus mucosa. In advanced cases, the oxyntic epithelia are replaced by atrophic(and metaplastic) mucosa, creating the phenotypic background in which both gastric neuroendocrine tumors and(intestinal-type) adenocarcinomas may develop. Despite improvements in our understanding of the phenotypic changes or cascades occurring in this autoimmune setting, no reliable biomarkers are available for identifying patients at higher risk of developing a gastric neoplasm. The standardization of autoimmune gastritis histology reports and classifications in diagnostic practice is a prerequisite for implementing definitive secondary prevention strategies based on multidisciplinary diagnostic approaches integratingendoscopy, serology, histology and molecular profiling.

关键词： Autoimmune gastritis metaplasia Carcinoids Operati

Corrigendum to“Back-analysing rock mass modulus from monitoring data of two tunnels in Sydney,Australia”[J Rock mech Geotech Eng 5(2017)877e891]

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Journal of Rock mechanics and Geotechnical Engineering 2018年第1期10卷 195-196页

作者： robert Bertuzzi Pells Sullivan meynink North RydeNSW 2113Australia School of Civil and Environmental Engineering University of New South WalesKensingtonNSW 2052Australia

The recent paper by Bertuzzi(2017)published in Journal of Rock mechanics and Geotechnical Engineering(JRmGE)included the correlation of rock mass deformation modulus,m,with the Q-value as presented in the first part of Barton(1995).This is reproduced here as Eq.(1):m=10Q1/3(1)The unconfined compressive strength(UCS)normalised Q-value,Qc,was introduced in later pages of the article by Barton(1995)to improve the correlation of rock mass quality and seismic *** Qc value is obtained by normalising to nominal hard rock compression strength value of 100 mPa as given in Eq.(2):

关键词： The recent paper by Bertuzzi(2017)published

Resolution of acute gastroenteritis symptoms in children and adults treated with a novel polyphenol-based prebiotic

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World Journal of Gastroenterology 2014年第34期20卷 12301-12307页

作者： Telma Noguera robert Wotring Chris R melville Kara Hargraves Jochen Kumm John m morton Instituto Centroamericano de Investigación Clínica Managua 050-008-4Nicaragua Greenteaspoon Inc StanfordCA 94305United States Department of Biology Stanford UniversityStanfordCA 94305United States Bariatric and minimally Invasive Surgery Stanford School of MedicineStanfordCA 94305United States

AIm: To test efficacy and durability of a polyphenol-based prebiotic treatment for acute gastroenteritis in a 300 patient double-blinded clinical study.

关键词： Prebiotic Gastroenteritis Diarrhea Rotavirus Infant mortality Dehydration Heartburn Polyphenol Aliva Greenteaspoon

Dietary manipulation and testosterone replacement therapy may explain changes in body composition after spinal cord injury: A retrospective case report

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World Journal of Clinical Cases 2019年第17期7卷 2427-2437页

作者： Ashraf S Gorgey robert m Lester mina P Ghatas Sakita N Sistrun Timothy Lavis Spinal Cord Injury and Disorders Service Hunter Holmes McGuire VAMCRichmondVA 23249United States Department of Physical medicine and Rehabilitation Virginia Commonwealth UniversityRichmondVA 23249United States Bionutrition Service Center for Clinical and Translational ResearchVirginia Commonwealth UniversityRichmondVA 23249United States

BACKGROUND Reduced level of physical activity,high-fat diet and skeletal muscle atrophy are key factors that are likely to contribute to deleterious changes in body composition and metabolic following spinal cord injury (SCI).Reduced caloric intake with lowering percentage macronutrients of fat and increasing protein intake may likely to improve body composition parameters and decrease ectopic adiposity after *** To highlight the effects of dietary manipulation and testosterone replacement therapy (TRT) on body composition after SCI mETHODS A 31-year-old male with T5 SCI was administered transdermal TRT daily for 16 *** intake and percentage macronutrients were analyzed using dietary *** resonance imaging and dual-energy x-ray absorptiometry were used to measure changes in body *** Caloric intake and fat percentage were reduced by 445 kcal/d and 6.5%,*** body weight decreased by 8%,body fat decreased by 29%,and lean mass increased by 7%.Thigh subcutaneous adipose tissue cross-sectional area was reduced by 31%.CONCLUSION manipulation of caloric intake,fat percentage,and protein percentage may have influenced body composition after SCI.

关键词： Spinal cord injury Diet High-protein Low-fat Nutrients Basal metabolic rate Case report

Higher incidence of steroid-induced ocular hypertension in keratoconus

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Eye and Vision 2016年第1期3卷 29-36页

作者： Anastasios John Kanellopoulos Emerson m.Cruz robert Edward T.Ang George Asimellis Laservision.gr Clinical and Research Eye Institute 17 Tsocha StreetAthens Postal Code:11521Greece NYU medical School New YorkNYUSA Asian Eye Institute MakatiPhilippines

Background:To compare intraocular pressure(IOP)changes following topical dexamethasone administration for 1 month in keratoconic versus normal ***:This is a retrospective,single-center,non-randomized case series evaluation of 350 *** groups were formed:normal/control Group A(n_(A)=73),eyes that underwent excimer laser photorefractive keratectomy;and keratoconic(KCN)Group B(n_(B)=277),eyes that were subjected to partial laser photorefractive keratectomy combined with collagen cross-linking(The Athens Protocol).All eyes received the same post-operative regimen of topical dexamethasone 0.1%for at least 1 *** applanation tonometry IOP readings and central corneal thickness(CCT)measurements were *** with induced ocular hypertension(OHT,defined as post-operative IOP higher than 21 mmHg),were identified and correlated to refractive procedure,gender,and corneal ***:At 4 weeks postoperatively,OHT was noted on 27.4%(20/73 eyes)in Group A,and 43.7%(121/277 eyes)in KCN Group B,(pmonths post-operatively(following 5-months of discontinuing topical dexamethasone treatment and commencing treatment of IOP-lowering medications),OHT rate was 1.8%in Group A and 3.9%in the KCN Group ***:This study demonstrates a potentially significant pre-disposition of keratoconic eyes to the development of steroid-induced OHT.

关键词： Keratoconus Intraocular pressure Corticosteroid induced ocular hypertension IOP spike Corneal collagen cross-linking CXL The Athens protocol Topography-guided Photorefractive keratectomy Dexamethasone topical ophthalmic solution