检索结果-南通市图书馆

Chinese Journal of Polymer Science 2008年第5期26卷 553-559页

作者： Vladimir Zakharov ludmila echevskaya Tatiana Mikenas Mikhail Matsko Andrey Tregubov Marina Vanina Marina Nikolaeva Boreskov Institute of Catalysis Novosibirsk 630090Russia

The effect of chemical composition of highly active supported Ziegler-Natta catalysts with controlled morphology on the MWD of PE has been *** was shown the variation of transition metal compound in the MgCl_2-supported catalyst affect of MWD of PE produced in broad range:Vanadium-magnesium catalyst(VMC)produce PE with broad and bimodal MWD(M_w/M_n=14-21).MWD of PE,produced over titanium-magnesium catalyst(TMC)is narrow or medium depending on Ti content in the catalyst(M_w/M_n=3.1-4.8).The oxidation ...

关键词： Polyethylene(PE) Vanadium magnesium catalyst(VMC) Titanium magnesium catalyst(TMC) Gel permeation chromatography(GPC) Molecular weight distribution(MWD).

Application of comprehensive two-dimensional gas chromatography with masss pectrometric detection for the analysis of selected drug residues in wastewater and surface water

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2013年第1期25卷 204-212页

作者： Petr Lacina ludmila Mravcov Milada Vvrov Institute of Chemistry and Technology of Environmental Protection Faculty of ChemistryBrno University of Technology Geotest a.s.Smahova 1244/112Brno 62700Czech Republic

Pharmaceutical residues have become tightly controlled environmental contaminants in recent years, due to their increasing concentration in environmental components. This is mainly caused by their high level of production and everyday consumption. Therefore there is a need to apply new and sufficiently sensitive analytical methods, which can detect the presence of these contaminants even in very low concentrations. This study is focused on the application of a reliable analytical method for the analysis of 10 selected drug residues, mainly from the group of non-steroidal anti-inflammatory drugs （salicylic acid, acetylsalicylic acid, ctofibric acid, ibuprofen, acetaminophen, caffeine, naproxen, mefenamic acid, ketoprofen, and dicofenac）, in wastewaters and surface waters. This analytical method is based on solid phase extraction, derivatization by N-methyl-N-（trimethylsilyl）trifluoroacetamide （MSTFA） and finally analysis by comprehensive two-dimensional gas chromatography with Time-of-Flight mass spectrometric detection （GC×GC- TOF MS）. Detection limits ranged from 0.18 to 5 ng/L depending on the compound and selected matrix. The method was successfully applied for detection of the presence of selected pharmaceuticals in the Svratka River and in wastewater from the wastewater treatment plant in Brno-Modrice, Czech Republic. The concentration of pharmaceuticals varied from one to several hundreds of ng/L in surface water and from one to several tens of μg/L in wastewater.

关键词： non-steroidal anti-inflammatory drugs solid phase extraction derivatization comprehensive two-dimensional gaschromatography surface water wastewater

Breeding versus survival:proximate causes of abrupt population decline under environmental change in a desert rodent,the midday gerbil(Meriones meridianus)

在线全文

学校读者我要写书评

暂无评论

Integrative Zoology 2019年第4期14卷 366-375页

作者： Andrey TCHABOVSKY ludmila SAVINETSKAYA Elena SURKOVA Laboratory for Population Ecology A.N.Severtsov Institute of Ecology and EvolutionRussian Academy of SciencesMoscowRussia

Studying abrupt ecological shifts under gradual environmental change caused,in particular,by human activity is important for understanding the fundamental aspects and underlying mechanisms of ecological *** of the rare well-documented examples of an abrupt ecological shift is the delayed step transition of the population of a desert rodent,the midday gerbil(Meriones meridianus),from high-abundance(1994-2002)to low-abundance(2003-2017)*** was in response to landscape transformation from desert to steppe caused by the drastic reduction of livestock in the rangelands of southern Russia after the collapse of the USSR in the early *** this study,we tested whether demographic parameters were correlated with the observed abrupt downward population *** found that reproductive activity(the percentage of breeding females,the number of litters,fecundity and the number of young recruited per female)showed no trend over time and did not differ between periods of high and low *** contrast,the adult sex ratio(SR=males:females)decreased significantly with time and was as much as twice more female-biased for the low-abundance population ***,SR was not related to any reproductive parameter,including the percentage of breeding fe*** conclude that proximate reasons for an abrupt population decline in *** are not associated with the changes in breeding patterns or mate limitation caused by the Allee effect but relate to the increased mortality as a result of the desert landscape being fragmented by *** mortality is expected to be higher for males as the mobile and dispersing sex.

关键词： demography landscape change rangelands reproduction threshold population dynamics

β-Carotene-properties and production methods

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Food Quality and Safety 2018年第2期2卷 69-74页

作者： ludmila Bogacz-Radomska Joanna Harasym Department of Biotechnology and Food Analysis Faculty of Engineering and EconomicsWroclaw University of EconomicsWroclawPoland epartment of Agriculture and Forestry Engineering College of Agricultural and Forestry EngineeringUniversity of ValladolidValladolidSpain

β-Carotene belongs to a group of more than 600 compounds,jointly called as *** has numerous biological functions in the human body and because human is not able to synthesize any of them,it is necessary to supply these valuable compounds with food or ***,therefore,market demand stimulates the development of its diverse production ***β-carotene was recovered from plants by physicochemical extraction and mainly from ***β-carotene is mainly produced through chemical *** quite recently biotechnology makes a great approach towardβ-carotene production as bioactive compounds of natural origin reveal higher bioaccessibility and higher consumer trust on market.

关键词： β-carotene properties production methods

Analysis of EX5del4232ins268 and EX5del955 PAH gene mutations in Ukrainian patients with phenylketonuria

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Genes & Diseases 2017年第2期4卷 108-110页

作者： Volodymyr Pampukha Maryna Nechyporenko ludmila Livshyts Institute of Molecular Biology and Genetics of the National Academy of Sciences of Ukraine Department of Human Genomics150Zabolotnogo str.03680 KyivUkraine

Phenylketonuria(PKU)is an autosomal recessive metabolic disorder caused by deficiency of phenylalanine hydroxylase(PAH).The major molecular defects causing PKU are missense mutations of PAH *** deletions of exon 5(EX5del955 and EX5del4232ins)were first reported by the Czech study and were later found also in the Polish,Slovak,Slovenian and Italian *** observations demonstrate the existence of a common subset of this mutation predominantly among Central European populations of Slavic *** is why we suggest that EX5del1955 and EX5del4232ins268 mutations might be frequent causes of PKU in Ukrainian ***5del955 and EX5del4232ins268 mutations were analyzed in 106 unrelated PKU patients negative for PAH gene mutations on one or both alleles from our previous *** simultaneous detection of EX5del4232ins268 and EX5del955 mutations was performed by PCR amplification of mutant ***5del955 mutation was not detected in the Ukrainian *** relative alleles frequency of EX5del4232ins268 mutation in the Ukrainian PKU population was determined as 1,66%.Our findings can be the one more evidence of Central European Slavic origin of EX5del4232ins268 mutation,suggested *** finding is important for the improvement of DNA diagnosis necessary for the management of PKU patients from Ukraine.

关键词： Large deletions Mutation analysis Phenylalanine hydroxylase Phenylketonuria

Inflammatory priming of mesenchymal stem cells:Focus on growth factors enhancement

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

BIOCELL 2022年第9期46卷 2049-2052页

作者： ALEKSANDRA GORNOSTAEVA ELENA ANDREEVA ludmila BURAVKOVA Cell Physiology Laboratory Institute of Biomedical Problems of Russian Academy of SciencesMoscow123007Russia

Multipotent mesenchymal stromal cells(MSCs)are actively involved in reparation and inflammation processes,providing damaged tissue reparation and suppressing immune cell responses in *** effects are mostly due to the production of a wide range of paracrine factors,including growth factors and immunomodulatory *** induce immunosuppressive activity,MSCs are primed by inflammatory cytokines,which results in an increased production of immunomodulatory ***,stimulation of reparative properties is also *** viewpoint manuscript highlights the possibilities of inflammatory priming to increase the production of growth factors by MSCs.

关键词： Multipotent mesenchymal stromal cells Priming Growth factors

Effect of the overconsolidation ratio of soils in surface settlements due to tunneling

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Research in Cold and Arid Regions 2013年第5期5卷 637-643页

作者： ludmila Strokova Institute of Natural Resources National Research Tomsk Polytechnic University

Construction of urban tunnels requires the control of surface subsidence to minimize any disturbance to nearby buildings and services. Past study of surface subsidence has been limited to mainly empirical solutions based on field studies, and very few analytical studies have been carried out. The available analytical solutions are not sufficient to include complex ground conditions; hence, a comprehensive analytical solution coupled with numerical modeling is necessary to model the effect of surface subsidence due to tunneling. This paper presents the results of modeling of surface settlements due to tunneling using the finite element method. The effect of the overconsolidation ratio of soils expressed in terms of the co- efficient of earth pressure at rest （K0） on surface subsidence due to tunneling is investigated. It is demonstrated that surface settlements appear to be sensitive to K0 values, and for geotechnical calculations pertaining to overconsolidated sand and clay soil, K0 values of 0.6 and 0.8, respectively, are proposed.

关键词： surface settlement trough coefficient of earth pressure at rest

Ultrastructure and histochemistry of rat myocardial capillary endothelial cells in response to diabetes and hypertension

在线全文

学校读者我要写书评

暂无评论

Cell Research 2005年第7期15卷 532-538页

作者： ludmila OKRUHLICOVA,Narcis TRIBULOVA1,Peter WEISMANN,Ruzena SOTNIKOVA Institute for Heart Research Slovak Academy of Sciences 840 05 Bratislava Slovak Republic Institute for Heart Research Slovak Academy of Sciences 840 05 Bratislava Slovak Republic Medical Faculty Comenius University Bratislava Slovak Republic Institute of Experimental Pharmacology Slovak Academy of Sciences Bratislava Slovak Republic

Insufficient growth and rarefaction of capillaries, followed by endothelial dysfunction may represent one of the mostcritical mechanisms involved in heart damage. In this study we examined histochemical and ultrastructural changes inmyocardial capillary endothelium in two models of heart failure streptozotocin-induced diabetes mellitus (STZ) and NO-deficient hypertension in male Wistar rats. Diabetes was induced by a single i.v. dose of STZ (45 mg/kg) and chronic 9-week stage was analysed. To induce NO-deficient hypertension, animals were treated with inhibitor of NO synthase L-nitroarginine methylester (L-NAME) (40 mg/kg) for 4 weeks. Left ventricular tissue was processed for enzyme cata-lytic histochemistry of capillary alkaline phosphatase (AlPh), dipeptidyl peptidase IV (DPP IV), and endothelial NOsynthase/NADPH-diaphorase (NOS) and for ultrastructural analysis. In diabetic and hypertensive rats, lower/absentAlPh and DPP IV activities were found in focal micro-areas. NOS activity was significantly reduced and persisted onlylocally. Quantitative evaluation demonstrated reduction of reaction product intensity of AlPh, DPP and NOS by 49.50%,74.36%, 20.05% in diabetic and 62.93%, 82.71%, 37.65% in hypertensive rats. Subcellular alterations of endothelialcells were found in heart of both groups suggesting injury of capillary function as well as compensatory *** injury was more significant in diabetic animals, in contrast the adaptation was more evident in hypertensiveones. Concluding: both STZ-induced diabetes- and NO-deficient hypertension-related cardiomyopathy were accompa-nied by similar features of structural remodelling of cardiac capillary network manifested as angiogenesis and *** latter was however, predominant and may accelerate disappearance of capillary endothelium contributing to myo-cardial dysfunction.

关键词： rat heart diabetes NO-deficiency capillary ultrastructure histochemistry.

HIFs in hypoxic regulation of the extracellular matrix:focus on little-known player HIF-3

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

BIOCELL 2024年第5期48卷 677-692页

作者： ALEKSANDRA GORNOSTAEVA ludmila BURAVKOVA MARGARITA LOBANOVA ELENA ANDREEVA Institute of Biomedical Problems of the Russian Academy of Sciences Khoroshevskoye Shosse 76AMoscow123007Russia

The structural and associated molecules of the extracellular matrix(ECM)complex is an important component of the local milieu of cells,both for maintaining their functions and *** is a dynamic structure that is finely tuned to changes in the *** of these factors is hypoxia,which can arise in tissues due to physiological or pathological *** a result of the hypoxic effect,the properties of the ECM are significantly modified,stiffness increases,the balance between degradation and synthesis of structural proteins shifts,and the deposition of biologically active mediators’***-inducible factors(HIFs)contribute significantly to the modification of the properties of the ECM under *** the three HIF isoforms,HIF-1 is the most studied,with numerous identified target genes encoding proteins that participate in all matrisome *** less is known about HIF-2 and *** the context of the effects of hypoxia on the matrisome,HIF-3 isoform is of particular *** the first two isoforms,transiently expressed during the first hours of hypoxia,HIF-3 is activated after around 24 h of exposure to hypoxia and persists for a longer *** addition,its transcription is more pronounced under hypoxia than are HIFs 1 and ***-3,rather than the first two isoforms,is possibly responsible for the changes that occur in matrisome during prolonged hypoxic *** review attempts to summarize the available data on the involvement of HIF-3 in the matrisome modification under hypoxia.

关键词： Hypoxia Hypoxia-inducible factors Matrisome

Two mutations in the truncated Rep gene RBR domain delayed the Wheat dwarf virus infection in transgenic barley plants

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 Integrative Agriculture 2018年第11期17卷 2492-2500页

作者： Pavel Cejnar ludmila Ohnoutkova Jan Ripl Tomas Vlcko Jiban Kumar Kundu Division of Crop Protection and Plant Health Crop Research Institute Prague 16106 Czech Republic Department of Chemical Biology and Genetics Centre of the Region Hana for Biotechnological and Agricultural Research Palack~/ University Olomouc 78371 Czech Republic

Wheat dwarf virus （WDV）, an important cereal pathogen, is closely related to Maize streak virus （MSV）, a model virus of the Mastrevirus genus. Based on its similarity to known MSV resistance strategies, a truncated part of the WDV replication- associated （RepA） gene （WDVRepA215） and the WDV RepA gene with a mutated retinoblastoma-related protein （RBR） interaction domain （WDVRepA215RBRre^t） were cloned into the plPKb002 expression vector and transformed into immature embryos of spring barley cv. Golden Promise plants through Agrobacterium-mediated transformation. A detailed study of T1-generation plants infected by leafhoppers （Psammotettix alienus） fed on infection sources of variable strength was performed over a 5-week period encompassing the initial stages of virus infection. A DNA WDV TaqMan qPCR assay normalized using the DNA puroindoline-b SYBR Green qPCR assay for samples on a per week basis revealed an approximately 2-week delay in WDVRepA215RBR^mut plants to WDVRepA215 plants before significant increases in the WDV viral levels occurred. Both WDVRepA215 and WDVRepA215RBR^mut plants showed similar levels of transgenic transcripts over the screened period; however, the transgenic plants also showed increased numbers of infected plants compared to the control plants.

关键词： Wheat dwarf virus (WDV) truncated Rep gene RBR domain qPCR screening