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Stereological study of the effects of vitamin E on testis structure in rats treated with para-nonylphenol

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Asian journal of Andrology 2009年第4期11卷 508-516页

作者： m Soleimani m.hranjani A Noorafshan hr momeni mH Abnosi m mahmoodi m Anvari Sm Hoseini Biology Department Arak University Arak 38156 Iran Anatomy Department Shiraz University of Medical Sciences Shiraz 71348 Iran Anatomy Department Research and Clinical Center for Infertility Shahid Sadoughi University of Medical Sciences Yazd 89195-999 Iran

This study was organized to see whether vitamin E, as a strong antioxidant, could affect the abnormalities of testis structure caused by para-nonylphenol （p-Np） during its development. A total of 32 female Wistar rats after mating were divided into four groups （n = 8）： control, vitamin E （100 mg kg^-1 per day）, p-Np （250 mg kg^-1 per day） and p-Np ＋ vitamin E. The rats were treated from the seventh day of pregnancy till the twenty-first day. After weaning, the male pups were divided into the same groups and were treated orally for 90 days. Finally, the right testis was fixed, processed, stained and studied using stereological methods. The weight and volume of testis, volume of seminiferous tubules and its diameter, thickness of the basement membrane, height of the germinal epithelium, total number of types A and B spermatogonia, spermatocyte, spermatid and Sertoli cells were significantly reduced in p-Np group when compared with other groups. Co-administration of vitamin E and p-Np compensated for the adverse effects of p-Np on the above parameters. In addition, treatment with only vitamin E caused a significant increase in diameter, basement membrane thickness and height of germinal epithelium, number of spermatogonia and spermatocytes. Co-administration of vitamin E with p-Np could prevent the adverse effects ofp-Np on the testis structure during its development.

关键词： development para-nonylphenol stereology testis vitamin E

ENERGY ESTImATES FOR DELAY DIFFUSION-REACTION EQUATIONS

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journal of Computational mathematics 2008年第4期26卷 536-553页

作者： j.A.Ferreira p.m.daSilva CmUC-Departamento Departamento

In this paper we consider nonlinear delay diffusion-reaction equations with initial and Dirichlet boundary conditions. The behaviour and the stability of the solution of such initial boundary value problems （IBVps） are studied using the energy method. Simple numerical methods are considered for the computation of numerical approximations to the solution of the nonlinear IBVps. Using the discrete energy method we study the stability and convergence of the numerical approximations. Numerical experiments are carried out to illustrate our theoretical results.

关键词： Delay diffusion reaction equation Energy method Stability Convergence.

Can a polymorphism in the thalassemia gene and a heterozygote CFTR mutation cause acute pancreatitis?

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World journal of Clinical Cases 2014年第3期2卷 62-66页

作者： j-matthias L?hr Stephan Haas Gastrocentrum Karolinska Institutet and University Hospital Division of molecular Gastroenterology Department of Medicine Ⅱ Medical Faculty Mannheim University of Heidelberg

The case of a 32-year-old black woman of African descent who suffered from repeated episodes of acute pancreatitis, initially triggered when flying on airplanes, is reported. She did not drink alcohol or smoke. Genetic analysis was negative for cationic trypsinogen, serine protease inhibitor Kazal type 1 and chymotrypsin C. However, hemoglobin F was elevated. Sequencing of the thalassemia gene revealed a novel alteration in the 5' region indicative of a functional abnormality of the molecule. Sequencing the cystic fibrosis transmembrane conductance regulator(CFTR) gene revealed a heterozygote sequence variant. The combination of a hemoglobin gene mutation known for thalassemia in conjunction with the hitherto undescribed CFTR mutation is suggested to pave the road for initial and repetitive pancreatitis attacks. This will be discussed.

关键词： Acute pancreatitis Hypoxia Flying Thalassemia Hemoglobin Cystic fibrosis transmembrane conductance regulator Hereditary persistence of fetal hemoglobin

COmpOSITION AND RHEOLOGY OF pOLYAmIDE-6 OBTAINED BY USING BI-AND TRI-FUNCTIONAL COUpLING AGENTS

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Chinese journal of polymer Science 2013年第1期31卷 58-70页

作者： j.j.m. Slot E. van Ruymbeke p.A.m. Steeman materials Science Centre DSM Research Department of mathematics and Computer Science Eindhoven University of Technology

A statistical approach is developed, based on a monte Carlo method, in order to determine the statistical composition of a polyamide-6 sample composed of caprolactam （an AB-type monomer） and of a di-acid （A2 type） or a tri- acid （A3 type） as coupling agents. For this composition, the linear theological behavior of these systems is predicted using a tube-based theory. This allows us to show that while coupling agents of type A2 can be seen as flow improver, the effect of branching agents of type A3, depending on the synthesis recipe and the conversion level, can lead either to an increase or to a decrease of the viscosity. By adding specific amount of these agents, we also show that it is possible to obtain materials with the same zero-shear viscosity but with different shear thinning behavior. Furthermore, the polydispersity of linear samples of the same average number molecular weight, mn, is discussed in function of the amount of A2 monomers they contain. Ranging from 2 to 1.5, this difference in polydispersity is expected to have a significant influence on the processing behavior of such materials.

关键词： polyamide-6 Random branching Statistical composition Rheology monte Carlo Tube theory.

pOLYmERIC SURFACTANT STRUCTURE

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Chinese journal of polymer Science 2001年第2期19卷 135-145页

作者： p.m.Saville j.W.White Research School of Chemistry The Australian National University Canberra ACT 0200 AustraliaResearch School of Chemistry The Australian National University Canberra ACT 0200 Australia

polymeric surfactants are amongst the most widespread of all polymers. In nature, proteins and polysaccharidescause self organization as a result of this surfactancy; in industry, polymeric surfactants play key roles in the food, explosivesand surface coatings sectors. The generation of useful nano- and micro-structures in films and emulsions as a result ofpolymer amphiphilicity and the application of mechanical stress is discussed. The use of X-ray and neutron small anglescattering and reflectivity to measure these structures and their dynamic properties will be described. New results on linear and dendritic polymer surfactants are presented.

关键词： polymeric Surfactant Structure X-ray Neutron Reflectivity Film

REITERATED HOmOGENIZATION OF DEGENERATE NONLINEAR ELLIpTIC EQUATIONS

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Chinese Annals of mathematics,Series B 2002年第3期23卷 325-334页

作者： j.BYSTRm j.ENGSTRm p.WALL Dedicated to the memory of jacques-Louis Lions Dedicated to the memory of Jacques-Louis LionsDedicated to the memory of Jacques-Louis Lions

The authors study homogenization of some nonlinear partial differential equations of the form -div (?(hx, h2x,Duh)) =f, where a is periodic in the first two arguments and monotone in the third. In particular the case where a satisfies degenerated structure conditions is studied. It is proved that uh converges weakly in W01,1 (?) to the unique solution of a limit problem as h ? '. moreover, explicit expressions for the limit problem are obtained.

关键词： Homogenization Reiterated monotone Degenerated

ON THE UNIQUENESS OF THE WEAK SOLUTIONS OF A QUASILINEAR HYpERBOLIC SYSTEm WITH A SINGULAR SOURCE TERm

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Chinese Annals of mathematics,Series B 2002年第3期23卷 317-324页

作者： j.p.DIAS m.FIGUEIRA Dedicated to the memory of jacques-Louis Lions Dedicated to the memory of Jacques-Louis Lions

This paper is a continuation of the authors' previous paper [1]. In this paper the authors prove, assuming additional conditions on the initial data, some results about the existence and uniqueness of the entropy weak... 详细信息

关键词： Cauchy problem Weak solution Quasilinear hyperbolic system

Arctic sea-ice extent: No record minimum in 2023 or recent years

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 52-55页

作者： Ola m.johannessen Tor I.Olaussen Nansen Scientific Society BergenNorway Nansen Environmental and Remote Sensing Center BergenNorway

Arctic sea-ice extent reaches its minimum each year in September. On 11 September 2023 the minimum was 4.969 million square kilometers(***^(2)). This was not a record low, which occurred in 2012, when the minimum was 4.175 ***^(2), 0.794 ***^(2) less than the minimum in 2023. However, the ice extent had decreased by 0.432 ***^(2) compared with 2022. Nevertheless, the summer melting in 2023 was remarkably less than expected when considering the strong heat waves in the atmosphere and ocean, with record temperatures set around the world. In general, there is a high correlation between the long-term decrease in sea-ice extent and the increasing CO_(2) in the atmosphere, where the increase of CO_(2) in recent decades explains about 80% of the decrease in sea ice in September, while the remainder is caused by natural variability.

关键词： Sea ice Arctic minimum ice Climate

Temporal dynamics of neonatal hypoxic-ischemic encephalopathy injuries on magnetic resonance imaging

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Neural Regeneration Research 2025年第11期20卷 3144-3150页

作者： Holly Flyger Samantha j.Holdsworth Alistair j.Gunn Laura Bennet Hamid Abbasi mātai medical Research Institute Tairāwhiti GisborneNew Zealand Department of Anatomy&medical Imaging Faculty of Medical and Health SciencesThe University of AucklandAucklandNew Zealand Center for Brain Research The University of AucklandAucklandNew Zealand Auckland Bioengineering Institute The University of AucklandAucklandNew Zealand

moderate to severe perinatal hypoxic-ischemic encephalopathy occurs in~1 to 3/1000 live births in high-income countries and is associated with a significant risk of death or neurodevelopmental *** assessment is important to help identify highrisk infants,to help families,and to support appropriate interventions.A wide range of monitoring tools is available to assess changes over time,including urine and blood biomarkers,neurological examination,and *** present,magnetic resonance imaging is unique as although it is expensive and not suited to monitoring the early evolution of hypoxic-ischemic encephalopathy by a week of life it can provide direct insight into the anatomical changes in the brain after hypoxic-ischemic encephalopathy and so offers strong prognostic information on the long-term outcome after hypoxic-ischemic *** review investigated the temporal dynamics of neonatal hypoxic-ischemic encephalopathy injuries,with a particular emphasis on exploring the correlation between the prognostic implications of magnetic resonance imaging scans in the first week of life and their relationship to long-term outcome prediction,particularly for infants treated with therapeutic hypothermia.A comprehensive literature search,from 2016 to 2024,identified 20 pertinent *** review highlights that while the optimal timing of magnetic resonance imaging scans is not clear,overall,it suggests that magnetic resonance imaging within the first week of life provides strong prognostic *** challenges limit the timing consistency,particularly the need for intensive care and clinical ***,although most reports examined the prognostic value of scans taken between 4 and 10 days after birth,there is evidence from small numbers of cases that,at times,brain injury may continue to evolve for weeks after *** suggests that in the future it will be important to explore a wider range of times after hypo

关键词： magnetic resonance imaging neonatal hypoxic-ischemic encephalopathy neurodevelopmental outcomes prognostic biomarkers in neuroimaging scan timing therapeutic hypothermia