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1.
SIRPA KAUNISTO PANU VÄLIMÄKI RAINE KORTET JANI KOSKIMÄKI SAULI HÄRKÖNEN ARJA KAITALA SAULI LAAKSONEN LAURA HÄRKÖNEN HANNU YLÖNEN 《Biological journal of the Linnean Society. Linnean Society of London》2012,106(2):275-286
The deer ked (Lipoptena cervi) is an ectoparasitic fly on cervids that has expanded its distribution rapidly in Northern Europe. However, the regulating biotic factors such as predation remain unknown. The host‐independent pupal stage of the fly lasts for several months. Blackish pupae are visible against snow, especially on the bedding sites of hosts, and are thus exposed to predators. To evaluate the role of predation on the invasion dynamics and evolution of L. cervi, we monitored pupal predation on artificial bedding sites in three geographical areas in Finland during winter. We explored: (1) possible predators; (2) magnitude of predation; and (3) whether predation risk is affected by host‐derived cues. We demonstrate that pupae are predated by a number of tit species. Any reddish brown snow discoloration on bedding sites, indicating heavy infestation of the host, serves as an exploitable cue for avian predators, thereby increasing the risk of pupal predation. The ability of tits to use this host‐derived cue seems to be dependent on the prevalence of L. cervi and the period of invasion history, which suggests that it may be a learned behavioural response. Predation by tits may potentially affect the L. cervi population dynamics locally. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 106 , 275–286. 相似文献
2.
Daniela Moralli David YL Chan Andrew Jefferson Emanuela V Volpi Zoia L Monaco 《BMC cell biology》2009,10(1):18-11
Background
Human artificial chromosomes (HAC) are small functional extrachromosomal elements, which segregate correctly during each cell division. In human cells, they are mitotically stable, however when the HAC are transferred to murine cells they show an increased and variable rate of loss. In some cell lines the HAC are lost over a short period of time, while in others the HAC become stable without acquiring murine DNA. 相似文献3.
M. A. Usacheva T. V. Nasedkina A. Yu. Ikonnikova A. V. Kulikov A. V. Chudinov Yu. P. Lysov E. V. Bondarenko P. A. Slominskii N. A. Shamalov I. M. Shetova S. A. Limborskaya A. S. Zasedatelev V. I. Skvortsova 《Molecular Biology》2012,46(2):192-199
The allele and genotype frequencies of 14 SNPs of renin-angiotensin (REN, AGT, AGTR1, AGTR2, BKR2, and ADRB2) and hemostasis (FGB, F2, F5, F7, ITGB3, SERPINE1, MTHFR) system genes, as well as of the ACE insertion-deletion polymorphism, were analyzed in patients with ischemic stroke and in healthy controls matched by age, sex, and ethnicity. Genotyping was performed through the amplification of the selected gene sequences and subsequent hybridization of the labeled fragments with SNP-specific DNA probes on the biochip. There were no significant differences in the allele frequencies of individual genes between the groups of stroke patients and healthy donors. The contribution of the renin-angiotensin and hemostasis system genes to the genetic susceptibility to ischemic stroke in Russians from central Russia was also assessed using the MDR (Multifactor Dimensionality Reduction) approach. The genotype combination FGB G/- x ACE I/- x MTHFR C/- x SERPINE1 5G/5G, the frequency of which was significantly higher in patients with stroke than in healthy controls, was associated with an increased risk of ischemic stroke (P = 0.03, OR = 2.4, 95%CI 1.1?C5.3). 相似文献
4.
Investigation of the influence of divalent metal cations on the induction of plasminogen catalytic activity by monoclonal
antibody IV-Ic showed that the presence of metal cations in the reaction medium changes the induction by slowing down or accelerating
the process. Ions of Zn2+, Mn2+, and Cu2+ completely inhibit activation. Ions of Co2+ and Ni2+ decrease the rate of the first and second phases of the reaction more than 2 times. Ca2+ ions do not have any effect on the activation rate. Ions of Mg2+, Ba2+, and Sr2+ increase the rate of the first phase of the reaction by 1.5, 2.0, and 2.0 times and the rate of the second phase by 2.0,
3.8, and 4.7 times, correspondingly. Sr2+ ions have the strongest stimulating effect on plasminogen activation by monoclonal antibody IV-Ic. Investigation of the dose
dependent effect of Sr2+ on the rate of plasminogen activation by monoclonal antibody IV-Ic showed stimulating effect of Sr2+ at concentrations from 0.1 to 1.0 mM with half maximum at 0.6 mM. However, Sr2+ ions do not affect amidolytic activity of plasmin and activation of plasminogen by streptokinase. Sr2+ ions also do not affect monoclonal antibody IV-Ic binding to plasminogen. The effect of Sr2+ is specific and mediated by the IV-Ic component. The presence of metal cations affects conformational changes in the process
of active site formation. Metal cations also affect structure of the plasminogen molecule active site in the complex with
monoclonal antibody IV-Ic and enzyme-substrate interaction. The effect of α2-antiplasmin on the induction of plasminogen catalytic activity by monoclonal antibody IV-Ic in range of concentrations from
5 to 30 nM has been studied. α2-Antiplasmin at concentration 30 nM almost completely inhibits induction of plasminogen catalytic activity by monoclonal antibody
IV-Ic at the ratio plasminogen/α2-antiplasmin of 3:1. This can be explained by competition of α2-antiplasmin and monoclonal antibody IV-Ic for the lysine-binding sites of plasminogen and inhibition of the active center
in activated complex plasminogen*—mAB IV-Ic. Divalent metal cations and α2-antiplasmin are important factors in induction of plasminogen catalytic activity by monoclonal antibody IV-Ic.
Published in Russian in Biokhimiya, 2006, Vol. 71, No. 6, pp. 778–785. 相似文献
5.
Cyanine dye-protein interactions: looking for fluorescent probes for amyloid structures 总被引:1,自引:0,他引:1
Volkova KD Kovalska VB Balanda AO Vermeij RJ Subramaniam V Slominskii YL Yarmoluk SM 《Journal of biochemical and biophysical methods》2007,70(5):727-733
We ascertained the ability to detect fibrillar beta-lactoglobulin (BLG) of a series of mono-, tri-, penta-, and heptamethinecyanines based on benzothiazole and benzimidazole heterocycles, and of benzothiazole squaraine. Fluorescence properties of these cyanine dyes were measured in the unbound state and in the presence of monomeric and fibrillar BLG and compared with those for the commercially available benzothiazole dye Thioflavin T. The correlation between the chemical nature of the dye molecules and the ability of dyes to bind aggregated proteins was established. We found that meso-substituted cyanines with amino substituents in heterocycle in contrast to the corresponding unsubstituted dyes have a binding preference to fibrillar BLG and a noticeable fluorescence response in the presence of the aggregated protein. For the squaraines and benzimidazole penthamethinecyanines studied, fluorescence emission increased both in the presence of native and fibrillar protein. The trimethinecyanines T-49 and SH-516 exhibit specifically increased fluorescence in the presence of fibrillar BLG. These dyes demonstrated the same or higher emission intensity and selectivity to aggregated BLG as Thioflavin T, and are proposed for application in selective fluorescent detection of aggregated proteins. 相似文献
6.
Marina V. Kuperman Svitlana V. Chernii Mykhaylo Yu. Losytskyy Dmytro V. Kryvorotenko Nadiya O. Derevyanko Yurii L. Slominskii Vladyslava B. Kovalska Sergiy M. Yarmoluk 《Analytical biochemistry》2015
The effect of various N,N′-substituents in the molecule of benzothiazole trimethine cyanine dye on its ability to sense the amyloid aggregates of protein was studied. The dyes are low fluorescent when free and in the presence of monomeric proteins, but their emission intensity sharply increases in complexes with aggregated insulin and lysozyme, with the fluorescence quantum yield reaching up to 0.42. 相似文献
7.
A genic male sterile Chinese cabbage, Brassica campestris L. ssp. chinensis Makino, was examined using cytological and cytochemical methods to characterize the process of pollen abortion in this plant.
Thick sections of both fertile and sterile anthers at different developmental stages were stained using Toluidine Blue O,
Periodic Acid-Schiff’s (PAS) reaction and Sudan Black B to detect cytochemical changes that may occur in the distribution
of insoluble polysaccharide and lipid storage bodies. Pollen abortion in sterile anthers occurs at an early stage of microspore
development. During early microspore development, reductions in the number of starch grains in the connective tissue of fertile
anthers coincide with the accumulation of starch grains in cells of the anther wall. In the late microspore stage, a large
vacuole forms in the microspore, and tapetal cells synthesize and accumulate lipid droplets. The cellular organization of
tapetal cells in sterile anthers appears similar to that in fertile anthers, except for the absence of lipid droplets in cells
of sterile anthers and diffusely labeled tapetal polysaccharides, suggesting defects in nutrient storage.
Supported by National Natural Science Foundation of CHINA (30170060) 相似文献
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9.
采用80%丙酮提取物的水萃取部位,利用凝胶、MCI、反相碳18、及 Toyopearl Butyl-650C 柱色谱进行分离纯化得到7个黄酮和3个苯乙醇苷类化合物。根据化合物的波谱数据分析鉴定为槲皮素(1)、槲皮苷(2)、异懈皮苷(3)、芦丁(4)、异牡荆素(5)、牡荆素(6)、木犀草素-7-O-α-L-鼠李糖(1→6)-β-D-葡萄糖苷(7)、2-phenethylβ-D-glucoside(8)、icariside D1(9)、2-苯乙基-D-芸香甙(10)。其中化合物1-3、5-6、8-10为首次从本属植物中分离得到。 相似文献
10.
Lavanya Balakrishnan Raja Sekhar Nirujogi Sartaj Ahmad Mitali Bhattacharjee Srikanth S Manda Santosh Renuse Dhanashree S Kelkar Yashwanth Subbannayya Rajesh Raju Renu Goel Joji Kurian Thomas Navjyot Kaur Mukesh Dhillon Shantal Gupta Tankala Ramesh Jois Vivek Vasdev YL Ramachandra Nandini A Sahasrabuddhe TS Keshava Prasad Sujatha Mohan Harsha Gowda Subramanian Shankar Akhilesh Pandey 《Clinical proteomics》2014,11(1):6