检索结果-南通市图书馆

Advances in Bioscience and Biotechnology 2012年第7期3卷 945-950页

作者： Lucijan Mohorovic vladimir Micovic Department of Environmental Medicine University of Rijeka School of Medicine Rijeka Croatia

The tested hypothesis points out that exposure to environmental toxic substances originating from coal or other fossil fuels burning is the most decisive for the impacts of the metabolic synergy of nitrogen oxides as oxidants that cause hemoglobin oxidation to methemoglobin, and sulphur dioxide metabolites as inhibitors of antioxidants, in the bloodstream throughout the period of pregnancy. The main difference between the present three-stage hypothesis and other hypotheses is the assertion that, in the pathogenesis of early and late complicated pregnancy, methemoglobin takes on an important role. Methemoglobin by itself and from heme, redox-active ferric iron as a product of methemoglobin catabolism, has prooxidant properties and causes important structural and functional changes in the vascular endothelium, such as growth arrest, senescence, morphological alterations and cell apoptosis. Our own prospective study of methemoglobin in pregnancy revealed a significant rise and correlation between the ground level of SO2 and the level of methemoglobin: >1.5 g/L (r = 0.72, p 2, NOx, NO, NO2 and others) and that is an early biomarker of the identification of women with a pregnancy risk, and having an significant role upon adverse effects on mother and fetus health.

关键词： Methemoglobinemia Mother and Fetal preeclampsia Three-Stage Disorders Environmental Oxidants Biomarker Nitrogen and Sulphur Synergy

Speed of Sound in Atmosphere of the Earth

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Acoustics 2012年第2期2卷 80-85页

作者： vladimir G. Kirtskhalia Ilia Vekua Sukhumi Institute of physics and Technology Tbilisi Georgia

It is demonstrated that contemporary conception on adiabaticity of sound in the Earth atmosphere is fair in sufficient approximation only for altitudes z ≤ 103 m. At higher altitudes adiabaticity of sound is violated and essential dependence of its speed on altitude is revealed which is related to heterogeneity of the atmosphere in gravitation field of the Earth. It became possible to reveal the factor of gravity field due to the fact that in the equation of the state of atmosphere considered to be ideal gas, the entropy s is taken into consideration and is written down as ρ = (p, s) instead of generally accepted ρ = ρ(p) which is fair only for isentropic media and is not applicable to the Earth. Such approach enabled to determine that apart from adiabatic mechanism of generation of sound wave there exists isobaric one and exactly this mechanism leads to dependence of sound speed on altitude which is the same as dependence on density.

关键词： Speed of Sound Atmosphere Compressibility Incompressibility

Common and small molecules as the ultimate regulatory and effector mediators of antigen-specific transplantation reactions

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Transplantation 2013年第4期3卷 54-61页

作者： vladimir Holan Magdalena Krulova Department of Transplantation Immunology Institute of Experimental MedicineAcademy of Sciences of the Czech Republic142 20 Prague 4Czech Republic Faculty of Science Charles University128 44 Prague 2Czech Republic

In spite of intensive research, the molecular basis of allograft and xenograft rejection still remains not fully understood. The acute rejection of an allograft is associated with the intragraft Th1 cytokine response, while tolerance of an allograft or xenograft rejection is accompanied by a higher production of the Th2 cytokines interleukin(IL)-4 and IL-10. Nevertheless, these cytokines are not the final regulatory and effector molecules mediating transplantation reactions. Data indicate that the functioning of common molecules with enzymatic activities, such are inducible nitric oxide synthase(i NOS), arginase, heme oxygenase-1(HO-1) or indoleamine-2,3-dioxygenase(IDO), the bioavailability of their substrates(L-arginine, tryptophan, heme) and the cytotoxic and regulatory actions of their small gaseous products(NO, CO) can be the ultimate mechanisms responsible for effector or regulatory reactions. Using models of transplantation immunity and tolerance we show that T cell receptor-mediated recognition of allogeneic or xenogeneic antigens as well as the balance between immunity/tolerance induces distinct cytokine production profiles. The ratio between Th1 and Th2 cytokines efficiently regulates the expression of genes for common enzymes, such as i NOS, arginase, HO-1 and IDO. These enzymes may compete for substrates, such as L-arginine or tryptophan, and the final product of their activity are small molecules(NO, CO) displaying effector or regulatory functions of the immune system. Thus, it is suggested that in spite of the high immunological specificity of transplatation reaction, the ultimate players in regulatory and effector functions could be small and common molecules.

关键词： Immunoregulation Graft rejection Tolerance Th1/Th2 balance Macrophages Nitric oxide Arginase

The Effects of Nanodiamonds at the Action of Colored Metal Ions on the Skin of Guinea pigs

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Biomaterials and Nanobiotechnology 2016年第4期7卷 214-224页

作者： Ekaterina Yu. Vasilyeva Victor I. prokhorenkov Alexey p. puzyr vladimir S. Bondar Krasnoyarsk State Medical University Named prof. V.F. Voyno-Yasenetsky Krasnoyarsk Russia Institute of Biophysics SB RAS Krasnoyarsk Russia

The protective effect of modified nanodiamonds (MND) under the action of cobalt and nickel ions on the skin of Guinea pigs was shown. At the action of chromium ions on the skin of animals, the protective effect of MND was not found. The differences are related to different adsorption properties of MND to the investigated colored metal ions. It is shown in vitro that MND can adsorb ions of cobalt and nickel and don’t bind ions of chromium from aqueous medium. The perspectives using of MND as a new drug for the prevention allergic dermatitis caused by action of bivalent ions of metals are discussed.

关键词： Nanodiamonds Allergic Contact Dermatitis Colored Metal Ions Clinical-Morphological Study

Nitrosative stress in human spermatozoa causes cell death characterized by induction of mitochondrial permeability transition-driven necrosis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2018年第6期20卷 600-607页

作者： pamela Uribe Maria E Cabrillana Miguel W Forn Favi/m Treulen Rodrigo Boguen vladimir Isachenko Evgenia Isachenko Ratil S inchez Juana V Villegas Center of Reproductive Biotechnology-Scientific and Technological Bioresource Nucleus（CEBIOR-BIOREN） University of La FronteraTemuco 4811230Chile Center of Excellence in Translational Medicine University of La FronteraTemuco 4810296Chile Department of Internal Medicine Faculty of MedicineUniversity of La FronteraTemuco 4781218Chile %aboratory of Andrology Research of Mendoza（LIAM）Institute of Histology and Embriology of Mendoza（IHEM）Histology and Embryology Area Department of Morphology and PhysiologySchool of MedicineNational University of Cuyo and CCT-MendozaCONICETMendoza 5500Argentin SResearch Institute（CIUDA） Medicine FacultyAcencagua UniversityMendoza 5500Argentina Research Group for Reproductive Medicine Cologne UniversityCologne 50937Germany Department of preclinical Sciences Faculty of MedicineUniversity of La FrenteraTemuco 4781218Chile.

peroxynitrite is a highly reactive nitrogen species and a potent inducer of apoptosis and necrosis in somatic cells. peroxynitrite-induced nitrosative stress has emerged as a major cause of impaired sperm function; however, its ability to trigger cell death has not been described in human spermatozoa. The objective here was to characterize biochemical and morphological features of cell death induced by peroxynitrite-mediated nitrosative stress in human spermatozoa. For this, spermatozoa were incubated with and without （untreated control） 3-morpholinosydnonimine （SIN-l）, in order to generate peroxynitrite. Sperm viability, mitochondrial permeability transition （MpT）, externalization of phosphatidylserine, DNA oxidation and fragmentation, caspase activation, tyrosine nitration, and sperm ultrastructure were analyzed. The results showed that at 24 h of incubation with SIN-l, the sperm viability was significantly reduced compared to untreated control （p〈 0.001）. Furthermore, the MpT was induced （p〈 0.01） and increment in DNA oxidation （p 〈 0.01）, DNA fragmentation （p 〈 0.01）, tyrosine nitration （p 〈 0.0001） and ultrastructural damage were observed when compared to untreated control. Caspase activation was not evidenced, and although phosphatidylserine externalization increased compared to untreated control （p 〈 0.001）, this process was observed in 〈10% of the cells and the gradual loss of viability was not characterized by an important increase in this parameter. In conclusion, peroxynitrite-mediated nitrosative stress induces the regulated variant of cell death known as MpT-driven necrosis in human spermatozoa. This study provides a new insight into the pathophysiology of nitrosative stress in human spermatozoa and opens up a new focus for developing specific therapeutic strategies to better preserve sperm viability or to avoid cell death.

关键词： necrosis nitrosative stress oxidative stress peroxynitrite sperm cell death

A positron source using an axially oriented crystal associated to a granular amorphous converter

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese physics C 2012年第9期36卷 871-878页

作者：徐成海 Robert Chehab peter Sievers Xavier Artru Michel Chevallier Olivier Dadoun 裴国玺 vladimir M.Strakhovenko Alessandro Variola Institute of High Energy physics Chinese Academy of Sciences Laboratoire de l'Accélérateur Linéaire IN2P3/CNRS et Université de Paris-SudBP 34-91898Orsay cedexFrance Institut de physique Nucléaire de Lyon IN2P3/CNRS et Université Lyon 169622 VilleurbanneFrance CERN CH-1211Genéve 23Switzerland Budker Institute of Nuclear physics Av.Lavrentyeva11630090 NovosibirskRussia

A non-conventional positron source using the intense y radiation from an axially oriented monocrys- tal which materializes into e^＋e^- pairs in a granular amorphous converter is described. The enhancement of photon radiation by multi-GeV electrons crossing a tungsten crystal along its 〈111〉 axis is reported. The resulting enhancement of pair production in an amorphous converter placed 2 meters downstream, is also re- ported. Sweeping off the charged particles from the crystal by a bending magnet upstream of the converter allows a significant reduction of the deposited energy density. Substituting a granular target made of small spheres for the usual compact one, makes the energy dissipation easier. The deposited energy and correspond- ing heating are analyzed and solutions for cooling are proposed. The configurations studied here for this kind of positron source allow its consideration for unpolarized positrons for the ILC.

关键词： channeling effect crystal positron source ILC

Characterization of pigeon paramyxoviruses (Newcastle disease virus) Isolated in Kazakhstan in 2005

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Virologica Sinica 2012年第2期27卷 93-99页

作者： Andrey Bogoyavlenskiy vladimir Berezin Alexey prilipov Eugeniy Usachev Ilya Korotetskiy Irina Zaitceva Aydyn Kydyrmanov Marat Sayatov Institute of Microbiology & Virology Almaty 050010 Kazakhstan D.I. Ivanovsky Institute of Virology Russian Academy of medical sciences Moscow 123098 Russia

Isolates of Newcastle disease virus (NDV) from deceased wild and domestic pigeons in Kazakhstan were obtained from the Almaty region during 2005 and were genotypically analyzed by using reverse transcription polymerase chain reaction (RT-pCR) with primers specific to the viral fusion (F) protein gene. part of the amplified F protein DNA product (nucleotide sequence 47-422) and the deduced amino acid sequences were compared phylogenetically with those from strains previously reported in other geographic regions. phylogenetic analysis indicated that the Kazakhstanian pigeon paramyxovirus type 1 (ppMV-1) isolates belong to genotype VI or 4bii. To our knowledge, this is the first reported VI isolates that possess the sequences of 112 GKRQKR116* F117 within the F0 protein. The information is fundamental to improving the efficiency of control strategies and vaccine development for NDV.

关键词： Newcastle disease virus paramyxovirus phylogenetic characterization pigeon

Generalization of Abelian Gauge Symmetry, Dark Matter and Cosmological Expansion

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Journal of Modern physics 2014年第1期5卷 34-43页

作者： Nikolay p. Tretyakov Alexandre Ya. Terletsky vladimir N. Lukash Maximo A. Agüero Astro Space Centre of Lebedev physics Institute Moscow Russia Department of Applied Mathematics State Social University of Russia Moscow Russia Department of Experimental physics Peoples’ Friendship University of Russia Moscow Russia Facultad de Ciencias Universidad Autonoma del Estado de Mexico Toluca Mexico

A commutative generalization of the U(1) gauge symmetry group is proposed. The two-parametric family of two-connected abelian Lie groups is obtained. The necessity of existence of so-called imaginary charges and electromagnetic fields with negative energy density (dark photons) is derived. The possibilities when the overall Lagrangian represents a sum or difference of two identical Lagrangians for the visible and hidden sectors (i.e. copies of unbroken U(1)) are ruled out by the extended symmetry. The distinction between the two types of fields resides in the fact that for one of them current and electromagnetic kinetic terms in Lagrangians are identical in sign, whereas for another type these terms are opposite in sign. As a consequence, and in contrast to the common case, like imaginary charges attract and unlike charges repel. Some cosmological issues of the proposed hypothesis are discussed. particles carrying imaginary charges are proposed as one of the components of dark matter. Such a matter would be imaginarily charged on a large scale for the reason that dark atoms carry non-compensated charges. It leads to important predictions for matter distribution, interaction and other physical properties being different from what is observed in dominant dark matter component in the standard model. These effects of imaginary charges depend on their density and could be distinguished in future observations. Dark electromagnetic fields can play crucial dynamical role in the very early universe as they may dominate in the past and violate weak energy condition which provides physical grounds for bouncing cosmological scenarios pouring a light on the problem of origin of the expanding matter flow.

关键词： Cosmology of Theories beyond the SM Cosmic Singularity Dark Energy Theory Dark Matter Theory

The Detection of partial Albinism at Three Species of Bats (Mammalia: Chiroptera) in European part of Russia

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Animal Sciences 2014年第5期4卷 291-296页

作者： Dmitriy G. Smirnov vladimir p. Vekhnik Nailya M. Kurmaeva Farid Z. Baishev Department of Zoology and Ecology Penza State University Penza Russia Zhiguli preserve p/o Bakhilova Polyana Samara Region Russia

The first time for the territory of European Russia describes the cases of catching bats with signs of albinism. This article describes the detection of three species of bats with partial albinism in European part of Russia. There are four animal units of Eptesicus serotinus turcomanus that are stored in penza State University. They were procured in Astrahan region in 1992 and in 1996. One more animal was found in Volgograd region in 2004. All these animals have white spots of different size and shape on their abdominal part of body. In 2012 it was caught a young female of pipistrellus nathusii in Samarskaya Luka (Samara region) and in 2013 the scientists found a mature female of Myotis mystacinus. Both animals had a light-colored fur, red eyes and with almost white ears. Moreover, they had pale-pink noses and extremities.

关键词： partial Albinism Eptesicus serotinus pipistrellus nathusii Myotis mystacinus

Catalytic Activity of Nanodiamonds in Azocoupling Reaction

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Biomaterials and Nanobiotechnology 2014年第3期5卷 173-178页

作者： Nikita O. Ronzhin Alexey p. puzyr Andrey E. Burov vladimir S. Bondar Institute of Biophysics SB RAS Krasnoyarsk Russia Special Design-Technology Bureau “Nauka” SB RAS Krasnoyarsk Russia

The catalytic efficiency of modified nanodiamonds (MND) in reactions of interaction between organic compounds was demonstrated on the example of azocoupling reaction (hydrogen peroxide-4-aminoantipyrine-phenol). It was found that catalytic action of MND was caused by redox active metal ions of Fe and Cu located on the MND surface. The neutralization of the ions significantly decreased catalytic properties of MND.

关键词： Diamond Nanoparticles Catalytic Activity Metal Ions Organic Reaction