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991.
N. P. Dem’yanchuk R. V. Oblap N. B. Novak M. D. Mel’nichuk 《Cytology and Genetics》2008,42(4):263-266
Studies of the genetic structure of the internal noncoding transcribed spacer region 2 (ITS2) of the ribosomal DNA of five entomophage species of the genus Trichogramma, i.e., T. pintoi Voeg., T. evanescens Westw., T. dendrolimi Mats., T. cacoeciae Meyer, and T. semblidis Auriv., are performed. A PCR analysis with subsequent determination of the nucleotide sequence of the ITS2 regions made it possible to identify essential inter-species differences. The data may be used for the identification of the species T. pintoi, T. dendrolini, and T. semblidis. 相似文献
992.
Yeh JL Liou SF Chang YP Lin SW Liu TS Wu BN Chen IJ Wu JR 《Journal of biomedical science》2008,15(3):375-389
The purpose of this study was to determine the efficacy and the possible mechanism of action of the synthesized drug isoeugenodilol
(a new third-generation β-adrenoceptor blocker) on the growth factor-induced proliferation of cultured rat vascular smooth
muscle cells (VSMCs) and neointimal formation in a rat carotid arterial balloon injury model. Isoeugenodilol significantly
inhibited 10% FBS, 20 ng/ml PDGF-BB, and 20 ng/ml vascular endothelial growth factor (VEGF)-induced proliferation. In accordance
with these findings, isoeugenodilol revealed blocking of the FBS-inducible progression through the G0/G1 to the S phase of the cell cycle in synchronized cells. Neointimal formation, measured 14 days after injury, was reduced
by the oral administration of isoeugenodilol (10 mg/kg/day). In an in vitro assay, isoeugenodilol inhibited the migration
of VSMCs stimulated by PDGF-BB. These findings indicate that isoeugenodilol shows an inhibitory potency on neointimal formation
due to inhibition of both migration and proliferation of VSMCs. In addition, isoeugenodilol in concentration-dependent manner
decreased the levels of phosphorylated ERK1/2 in both VSMCs and balloon-injured carotid arteries. The levels of phosphorylated
MEK1/2 and Pyk2 as well as intracellular Ca2+ and reactive oxygen species (ROS) were in concentration-dependent manner reduced by isoeugenodilol. Taken together, these
results indicate that isoeugenodilol may suppress mitogen-stimulated proliferation and migration partially through inhibiting
cellular ROS and calcium, and hence, through activation of the Pyk2-ERK1/2 signal pathway. This suggests that isoeugenodilol
has potential for the prevention of atherosclerosis and restenosis. 相似文献
993.
N. P. Chernobrovkina O. S. Dorofeeva M. K. Il’inova E. V. Robonen A. G. Vereshchagin 《Russian Journal of Plant Physiology》2008,55(3):365-371
The effect of boron availability on the content of fatty acids (FA) in the total lipids of needles was investigated in two-year-old seedlings of Scots pine (Pinus sylvestris L.). The study was conducted in the forest nursery on the soil deficient in boron. Various rates of boric acid (0.01, 0.03, 0.1, 0.3, 1, 3, and 10 g/m2) were applied to soil three times throughout the growth period. When pine seedlings were supplied with extra boron, the lipid content of the seedling needles declined. The optimal boron supply elevated the content of saturated FA in total needle lipids mostly at the expense of palmitic acid, with a corresponding decline in the level of unsaturated FA and unsaturation index of FA owing to trienoic FA (mainly linolenic and hexadecatrienoic acids). At the same time, the level of monoenoic and to a lesser degree dienoic acids increased. When boron supply of the seedlings was not optimal, the content of unsaturated and low-molecular FA increased. 相似文献
994.
Odabaş S Sayar F Güven G Yanikkaya-Demirel G Pişkin E 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2008,861(1):74-80
The aim of this study is to develop magnetically loaded nanosorbents carrying specific monoclonal antibodies (namely CD105 and CD73) for separation of mesenchymal stem cells from cell suspensions. Super-paramagnetic magnetite (Fe3O4) nanoparticles were produced and then coated with a polymer layer containing carboxylic acid functional groups (average diameter: 153 nm and polydispersity index: 0.229). In order to obtain the nanosorbents, the monoclonal antibodies were immobilized via these functional groups with quite high coupling efficiencies up to 80%. These nanosorbents and also a commercially available one (i.e., microbeads carrying CD105 antibodies from Miltenyi Biotec., Germany) were used for separation of CD105+ and CD73+ mesenchymal stem cells from model cell suspension composed of peripheral blood (97.6%), human bone marrow cells (1.2%) and fibroblastic cells (1.2%). The initial concentrations of the CD105+ and CD73+ cells in this suspension were measured as 5.86% and 6.56%, respectively. A flow-through separation system and a very simple homemade batch separator unit were used. We were able to increase the concentration of CD105+ cells up to about 86% in the flow-through separation system with the nanosorbents produced in this study, which was even significantly better than the commercial one. The separation efficiencies were also very high, especially for the CD73+ cells (reached to about 64%) with the very simple and inexpensive homemade batch unit. 相似文献
995.
996.
997.
Construction of an integrated consensus map of the apple genome based on four mapping populations 总被引:2,自引:0,他引:2
A. N’Diaye W. E. Van de Weg L. P. Kodde B. Koller F. Dunemann M. Thiermann S. Tartarini F. Gennari C. E. Durel 《Tree Genetics & Genomes》2008,4(4):727-743
An integrated consensus genetic map for apple was constructed on the basis of segregation data from four genetically connected crosses (C1?=?Discovery × TN10-8, C2?=?Fiesta × Discovery, C3?=?Discovery × Prima, C4?=?Durello di Forli × Fiesta) with a total of 676 individuals using CarthaGene® software. First, integrated female–male maps were built for each population using common female–male simple sequence repeat markers (SSRs). Then, common SSRs over populations were used for the consensus map integration. The integrated consensus map consists of 1,046 markers, of which 159 are SSR markers, distributed over 17 linkage groups reflecting the basic chromosome number of apple. The total length of the integrated consensus map was 1,032 cM with a mean distance between adjacent loci of 1.1 cM. Markers were proportionally distributed over the 17 linkage groups (χ 2?=?16.53, df?=?16, p?=?0.41). A non-uniform marker distribution was observed within all of the linkage groups (LGs). Clustering of markers at the same position (within a 1-cM window) was observed throughout LGs and consisted predominantly of only two to three linked markers. The four integrated female–male maps showed a very good colinearity in marker order for their common markers, except for only two (CH01h01, CH05g03) and three (CH05a02z, NZ02b01, Lap-1) markers on LG17 and LG15, respectively. This integrated consensus map provides a framework for performing quantitative trait locus (QTL) detection in a multi-population design and evaluating the genetic background effect on QTL expression. 相似文献
998.
Schmid H O'Callaghan P Nash MP Lin W LeGrice IJ Smaill BH Young AA Hunter PJ 《Biomechanics and modeling in mechanobiology》2008,7(3):161-173
The passive material properties of myocardium play a major role in diastolic performance of the heart. In particular, the shear behaviour is thought to play an important mechanical role due to the laminar architecture of myocardium. We have previously compared a number of myocardial constitutive relations with the aim to extract their suitability for inverse material parameter estimation. The previous study assumed a homogeneous deformation. In the present study we relaxed the homogeneous assumption by implementing these laws into a finite element environment in order to obtain more realistic measures for the suitability of these laws in both their ability to fit a given set of experimental data, as well as their stability in the finite element environment. In particular, we examined five constitutive laws and compare them on the basis of (i) "goodness of fit": how well they fit a set of six shear deformation tests, (ii) "determinability": how well determined the objective function is at the optimal parameter fit, and (iii) "variability": how well determined the material parameters are over the range of experiments. Furthermore, we compared the FE results with those from the previous study.It was found that the same material law as in the previous study, the orthotropic Fung-type "Costa-Law", was the most suitable for inverse material parameter estimation for myocardium in simple shear. 相似文献
999.
V. N. Zinov’eva I. N. Iezhitsa A. A. Spasov 《Biochemistry (Moscow) Supplemental Series B: Biomedical Chemistry》2008,2(2):133-147
Mechanisms of magnesium homeostasis intensively studied over the last 10–15 years by means of pathophysiological and molecular genetic approaches have been considered. Impairments of magnesium homeostasis causes the development of magnesium-deficient states, which have been found in many common diseases (diabetes mellitus, cardiovascular diseases, chronic fatigue syndrome, alcoholism, psychiatric and neurologic diseases, etc.), stress condition, effects of some environmental factors as well as therapy with some drugs. Special attention is paid to familial hypomagnesemias caused by genetic defects of magnesium transport systems. The review considers clinical and biochemical characteristics of twelve familial disorders including mechanisms of their development. Deeper understanding of mechanisms of regulation of magnesium homeostasis will results in the development of new approaches in diagnostics, prophylaxis and treatment of magnesium-deficient conditions. 相似文献
1000.
T. N. Borodina L. D. Rumsh S. M. Kunizhev G. B. Sukhorukov G. N. Vorozhtsov B. M. Feldman A. V. Rusanova T. V. Vasil’eva S. M. Strukova E. A. Markvicheva 《Biochemistry (Moscow) Supplemental Series B: Biomedical Chemistry》2008,2(2):176-182
The microcapsules with entrapped herbal water-soluble extracts of plantain Plantago major and calendula Calendula officinalis L. (PCE) were prepared by layer-by-layer (LbL)-adsorption of carrageenan and oligochitosan onto CaCO3 microparticles with their subsequent dissolving after the treatment of EDTA. Entrapment of PCE was performed by using adsorption and co-precipitation techniques. The co-precipitation provided better entrapment of PCE into the carbonate matrix compared to adsorption. In vitro release kinetics (AGJ) was studied using artificial gastric juice. Using the model of acetate ulcer in rats it has been demonstrated that PCE released from the microcapsules accelerates gastric tissue repair. 相似文献