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991.
Luszczki JJ Trojnar MK Trojnar MP Kimber-Trojnar Z Szostakiewicz B Zadrozniak A Borowicz KK Czuczwar SJ 《Canadian journal of physiology and pharmacology》2008,86(3):113-121
To assess the effect of 3 calcium channel antagonists (amlodipine, diltiazem, and verapamil) on the anticonvulsant action of topiramate (a new generation antiepileptic drug) in the mouse maximal electroshock seizure (MES) model. Amlodipine (20 mg/kg) significantly enhanced the anticonvulsant activity of topiramate in the MES test in mice, reducing its ED50 value from 54.83 to 33.10 mg/kg (p < 0.05). Similarly, diltiazem (5 and 10 mg/kg) markedly potentiated the antiseizure action of topiramate against MES, lowering its ED50 value from 54.83 to 32.48 mg/kg (p < 0.05) and 28.68 mg/kg (p < 0.01), respectively. In contrast, lower doses of amlodipine (5 and 10 mg/kg) and diltiazem (2.5 mg/kg) and all doses of verapamil (5, 10, and 20 mg/kg) had no significant impact on the antiseizure action of topiramate. Pharmacokinetic verification of the interaction of topiramate with amlodipine and diltiazem revealed that neither amlodipine nor diltiazem affected total brain topiramate concentration in experimental animals, and thus, the observed interactions were concluded to be pharmacodynamic in nature. The favorable combinations of topiramate with amlodipine or diltiazem deserve more attention from a clinical viewpoint because the enhanced antiseizure action of topiramate was not associated with any pharmacokinetic changes in total brain topiramate concentration. 相似文献
992.
Background
A smoker’s risk of diseases and death from smoking is closely related to his/her smoking duration. But little is known about the average length of smoking and the association between smoking duration and socio-economic status (SES) among Chinese smokers.Methods
A sample of male ever smokers (N = 2,637) aged 18+ years was drawn from the 2006 China Health and Nutrition Survey to examine the average length of smoking and socioeconomic differentials in smoking duration. Kaplan-Meier analysis was used to obtain median smoking duration. Log-logistic regression models were employed to estimate the relative duration of smoking, adjusted for demographic characteristics, smoking history, and health status.Results
Results showed that Chinese male ever smokers aged 18 years and older had a median duration of smoking of 58 years (95% CI: 56–61). Male ever smokers with a lower status job (i.e. farmers, manual and skilled workers, service workers, and office staff) had a significantly longer duration of smoking than those with a professional or administrative job after adjusted for demographic characteristics, smoking history, and health status. Individuals who earned the lowest income and who had no education or were being illiterate smoked for 11% and 14% longer, respectively, relative to those who had the highest income or who had college or above education.Conclusion
The findings demonstrated the problem of long smoking duration and a pattern of social disparities in smoking duration among Chinese male smokers. Social disparities in smoking behavior may exacerbate the already existing social inequalities in health. Thus, policies and interventions to promote smoking cessation should pay more attention to disadvantaged social groups. 相似文献993.
Kim HY Kim YA Kang S Lee HS Rhie HG Ahn HJ Nam HW Lee SE 《The Korean journal of parasitology》2008,46(3):199-201
Toxoplasma gondii is an obligate intracellular zoonotic protozoan with a worldwide distribution. It infects humans as well as a broad spectrum of vertebrate hosts. Cats and wild felidae play crucial roles in the epidemiology of toxoplasmosis. This study was performed to survey the prevalence of T. gondii infection among stray cats in the Gyeonggi-do, Republic of Korea. A total of 174 stray cat blood samples were collected from Gwacheon-si (n=20), Bucheon-si (82), and Yangju-si (72). Positive sera for T. gondii were identified in 14 samples (8.1%) exclusively via the latex agglutination test, 28 (16.1%) via ELISA, and 23 (13.2%) via PCR analysis. The overall infection rate of female stray cats (29.2%) presented as higher than that of male cats (24.0%). This study suggests that T. gondii is widespread in the stray cat population of Gyeonggi-do, Korea. It is urgently needed to control urban stray cat population and to reduce the risk of zoonotic transmission of toxoplasmosis to other animal hosts and humans. 相似文献
994.
Sa Peng Na Feng Meili Guo Yuehua Chen Qinghua Guo 《Biochemical Systematics and Ecology》2008,36(7):531-538
Genetic diversity of 23 populations of Carthamus tinctorius L. and two populations of Carthamus lanatus L. in China was investigated using Sequence-related Amplified Polymorphism (SRAP). All populations could be uniquely distinguished by 30 primer combinations with 483 bands and 274 polymorphic bands which generated 57% of polymorphic ratio. Unweighed pair-group method of with arithmetical averages (UPGMA) cluster analysis enabled construction of a dendrogram for estimating genetic distances among different populations. The extreme variation was observed when No. 4 cultivated and No. 13 wild population of C. lanatus were grouped at GS = 0.58, and separated from 23 populations of C. tinctorius at GS = 0.10. The result suggested that the cultivated and wild populations of C. lanatus had close relationship with each other and far relationship with C. tinctorius. Dendrogram also revealed a large genetic variation in 23 C. tinctorius populations; different primer combinations allowed them distinctly distinguished one from others with relatively low genetic similarity. Furthermore, five typical representative fragments in C. lanatus were obtained by four most informative primer combinations, which provided a possibility to distinguish C. lanatus from the C. tinctorius evidently. 相似文献
995.
Arthur Askeyev Oleg Askeyev Nur Yanybaev Igor Askeyev Sergey Monakhov Saša Marić Kees Hulsman 《Environmental Biology of Fishes》2017,100(5):585-596
Studies on assemblages of freshwater fishes along elevational gradients of rivers are lacking, even in Europe. In this paper we have explored the entire range of elevational gradients existing in the European part of Russia. We analyzed how fish biodiversity (species richness, abundance, diversity indices) at 435 river sites differed by elevation. The impact of elevation on the distribution of freshwater fish species was analyzed using regression and ordination methods. For the first time for a large area of Eastern Europe, optimum points and niche breadth for fish species along altitude gradients were estimated. Our analyses showed: (1) species richness and Shannon index decreased in the upper part of the gradient; fish abundance showed a unimodal response to elevation; highest numbers were found at elevations between 250 and 500 m; (2) ordination analysis demonstrated an upstream-downstream gradient of the fish assemblages; (3) regression analysis showed significant preferences for elevation by 19 species, all of which were monotonic; (4) optimum and niche breadth (tolerance) were highly variable between species; only five species (brown trout, grayling, common minnow, bullhead and stone loach) were encountered at elevations above 650 m; and (5) in our region, the habitat of grayling was higher in the mountains, and its abundance (numbers) at extreme elevations was greater, than brown trout. These results show how fish assemblages differ with elevation. Our findings identify the data that can be used for regional environmental monitoring of the state of small rivers and for aquatic conservation. 相似文献
996.
Genetic diversity and phylogenetic origin of brown trout Salmo trutta populations in eastern Balkans
Jan Kohout Alena Šedivá Apostolos Apostolou Tihomir Stefanov Saša Marić Muhammet Gaffaroğlu Vlastimil Šlechta 《Biologia》2013,68(6):1229-1237
The study focuses on the phylogenetic origin and genetic diversity of brown trout in the eastern part of the Balkan Peninsula. It further aims to reveal the impact of human-mediated transfers and stocking with non-indigenous trout on the populations in this area. For these purposes, mtDNA control region and microsatellite variation of 204 individuals from 16 populations were analysed. The results indicate that mtDNA haplotypes from the lower Danube basin and southern Black Sea basins differ substantially from a subclade of the Danubian lineage consisting of haplotypes found so far in the most of the Danube basin and in the Caspian and Aral Sea basins. Considering also the results of demographic analyses, this study evidences a complex evolutionary history of brown trout in the southern and western parts of the Black Sea basin. In the Aegean Sea basin, a high frequency of the central haplotype of Adriatic mtDNA lineage has been found. The other Adriatic lineage haplotypes found in this basin differ from the central haplotype by one mutational step only, indicating a recent evolution of the Adriatic lineage in the Aegean Sea basin. Substantial genetic differentiation among populations and basins was revealed. The hybridization with Atlantic brown trout was indicated in both sea basins, but especially in the Danube basin. Compared to other European regions, it can be inferred that the introgression of exogenous brown trout in the eastern Balkan populations is rather low. 相似文献
997.
Nucleosome remodeling by the human SWI/SNF complex requires transient global disruption of histone-DNA interactions 下载免费PDF全文
Aoyagi S Narlikar G Zheng C Sif S Kingston RE Hayes JJ 《Molecular and cellular biology》2002,22(11):3653-3662
We utilized a site-specific cross-linking technique to investigate the mechanism of nucleosome remodeling by hSWI/SNF. We found that a single cross-link between H2B and DNA virtually eliminates the accumulation of stably remodeled species as measured by restriction enzyme accessibility assays. However, cross-linking the histone octamer to nucleosomal DNA does not inhibit remodeling as monitored by DNase I digestion assays. Importantly, we found that the restriction enzyme-accessible species can be efficiently cross-linked after remodeling and that the accessible state does not require continued ATP hydrolysis. These results imply that the generation of stable remodeled states requires at least transient disruption of histone-DNA interactions throughout the nucleosome, while hSWI/SNF-catalyzed disruption of just local histone-DNA interactions yields less-stable remodeled states that still display an altered DNase I cleavage pattern. The implications of these results for models of the mechanism of SWI/SNF-catalyzed nucleosome remodeling are discussed. 相似文献
998.
对在大冷山自然保护区药用苔藓植物进行野外调查、样本采集,形态分类和鉴定,系统分析了其分布特征和药效功能.结果表明,该区域共有药用苔藓植物14科16属17种,其中包括3种苔类,14种藓类植物.17种药用苔藓植物中具有治疗烫伤或烧伤等功效的有4种,具有清热解毒治疗炎症作用的有7种,具有止血功效的有4种,对淋巴细胞白血病和神... 相似文献
999.
Jianghua Wang Dong Jiang Henghui Zhang Sa Lv Huiying Rao Ran Fei Lai Wei Professor 《Proteomics》2009,9(6):1672-1682
Hepatitis B virus (HBV) infection is a worldwide health problem and may develop to liver fibrosis, cirrhosis, and even hepatocellular carcinoma. To investigate the global proteome responses of liver‐derived cells to HBV infection and IFNα treatment, 2‐DE and MS‐based analysis were performed to compare the proteome changes between HBV stably transfected cell line HepG2.2.15 and its parental cell line HepG2, as well as HepG2.2.15 before and after IFNα treatment (5000 IU/mL for 72 h). Compared to HepG2, 12 of 18 down‐regulated and 27 of 32 up‐regulated proteins were identified in HepG2.2.15. After IFNα treatment, 6 of 7 down‐regulated and 11 of 14 up‐regulated proteins were identified. Differentially expressed proteins caused by HBV infection were involved with cytoskeletal matrix, heat shock stress, kinases/signal transduction, protease/proteasome components, etc. Prohibitin showed a dose‐dependent up‐regulation during IFNα treatment and might play a potent role in anti‐HBV activities of IFNα by enhancing the crossbinding p53 expression to achieve the apoptosis of HBV infected liver cells. Down‐regulation of interferon‐stimulated gene 15 (ISG15) in HepG2.2.15 and recovery by IFNα suggested its relationship with IFNα's anti‐HBV effect. 相似文献
1000.
In this study, 28 simple sequence repeat (SSR) primer sets were used to analyze the genetic diversity, population structure, and genetic relationships among 37 accessions of foxtail millet from Korea, China and Pakistan. A total of 298 alleles were detected with an average allele number of 10.6 per locus among 37 foxtail millet accessions. The number of alleles per locus ranged from 2 (b226) to 20 (b236). Of the 298 alleles, 138 alleles (46.3%) were rare (frequency < 0.05), 152 alleles (51.0%) were detected at an intermediate frequency (range, 0.05?C0.50), and eight alleles (2.7%) were abundant (frequency > 0.50), respectively. The average gene diversity values were 0.652, 0.692, and 0.491 and polymorphic information content values were 0.621, 0.653, and 0.438, for accessions from Korea, China, and Pakistan, respectively. The accessions from China showed higher SSR diversity than those from Korea and Pakistan. A phylogenetic tree constructed using the un-weighted pair group methods with arithmetic mean algorithm revealed three major groups of accessions that were not congruent with geographical distribution patterns with a few exceptions. The lack of correlation between the accession clusters and their geographic location indicates that the diffusion of foxtail millet from China to Korea might have occurred through multiple routes. Our results provide support for the origin and diffusion route of foxtail millet in East Asia. This SSR-based assessment of genetic diversity, genetic relationships, and population structure among genetic resources of foxtail millet landraces will be valuable to foxtail millet breeding and genetic conservation programs in Korea. 相似文献