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981.
Jang ZH Chung HC Ahn YG Kwon YK Kim JS Ryu JH Ryu do H Kim CH Hwang GS 《Molecular bioSystems》2012,8(7):2001-2009
Zebrafish (Danio rerio) is becoming a popular developmental biology model to study diseases and for drug discovery. In this study, we performed proton nuclear magnetic resonance spectroscopy ((1)H-NMR)- and gas chromatography-mass spectrometry (GC/MS)-based metabolic profiling of an alcoholic fatty liver using a zebrafish disease model. We examined metabolic differences between the control and alcoholic fatty liver groups in zebrafish to determine how metabolism in an alcoholic fatty liver is regulated. Multivariate statistical analysis showed a significant difference between the control and alcoholic fatty liver groups. The alcoholic fatty liver group showed increased excretion of isoleucine, acetate, succinate, choline, creatine, acetoacetate, 3-hydroxybutyrate (3HB), ethyl glucuronide (EtG), lactate/pyruvate ratio, fatty acids, and cholesterol, and decreased excretion of citrate, aspartate, tyrosine, glycine, glucose, alanine, betaine, and maltose. Metabolites identified in the fatty liver groups were associated with long-term alcohol consumption, which causes both oxidation-reduction (redox) changes and oxidative stress. This study suggests that global metabolite profiling in a zebrafish model can provide insights into the metabolic changes in an alcoholic fatty liver. 相似文献
982.
Persicaria thunbergii is a representative annual herb in Korean wetlands, widely inhabits not only in lentic wetlands, but also in unstable riparian
wetlands. To better understand the occupational strategy of this plant, we investigated environment, growth characteristics
before and after harsh flooding disturbance in FDA (flooding disturbed area) and NDA (non-disturbed area). Water level, fresh
soil moisture and organic matter of NDA were significantly higher than FDA. Before flooding disturbance, plant height, individual
length, number of node, individual biomass and biomass per 1 m2 were significantly higher in FDA than in NDA. After flooding disturbance, plant height, biomass per 1 m2, coverage and relative coverage were significantly lower in FDA than in NDA, yet individual length, number of node, individual
biomass and aerial seed production were not different. In FDA, creeping stems survive despite a flooding disturbance because
they are parallel with the water flow and are firmly fixed to the ground through numerous adventitious roots. Surviving creeping
stems make new shoots rapidly and P. thunbergii recovers its biomass during less than a month. Every regenerated shoots make reproductive organs. Thus, P. thunbergii can reproduce and successfully survive the next generation in the riparian habitat despite the harsh flooding disturbance
every year. 相似文献
983.
Nesibe Köse Ünal Akkemik Hasan Nüzhet Dalfes Mehmet Sinan Özeren Doğanay Tolunay 《Dendrochronologia》2012,30(4):295-301
Pinus nigra Arn. subsp. pallasiana (black pine) is one of the most widely grown tree in Turkey. It is the third most widely distributed tree species after Quercus L. and Pinus brutia Ten. Black pine grows in 20% of all forested areas in Turkey. In this dendroecological study, we identified the most important climate factors affecting radial growth of black pine in western Anatolia and classified its responses to climate. Twenty-eight site chronologies developed by different researchers were used in the analysis. Response functions were calculated for each chronology to identify the effect of climate on radial growth. Hierarchical cluster analysis was used to sort response functions and to classify the chronologies into groups based on climate responses. The individual responses of these chronologies to temperature and precipitation were classified in four main groups. Climatic and phytogeographic differences were the major factors influencing the formation of clusters. The results suggest that the major limiting factor is drought caused by low precipitation, especially in May, in almost all sites. The drought effect is much stronger in the transition region to the steppe, Central Anatolia and Mediterranean Regions than the Black Sea Region. Black pine trees respond positively to higher temperature at the beginning of growing season in almost all areas except in transition region to the steppe. 相似文献
984.
985.
Aspergillus fumigatus causes a wide range of diseases that include mycotoxicosis, allergic reactions and systematic diseases (invasive aspergillosis) with high mortality rates. In recent years, considerable progress in the genome sequencing of this fungus has been made by an international consortium, which includes the Wellcome Trust Sanger Institute (UK) and the Institute for Genome Research (USA). A tenfold whole genome shotgun sequence assembly of A. fumigatus has been made publicly available. In this study, it was attempted to identify the genes related to the phospholipid biosynthesis from the A. fumigatus genome by a gene prediction program (GlimmerM) and to reconstruct the metabolic pathway for phospholipids of A. fumigatus. Fifteen genes related to phospholipid pathway were identified in the A. fumigatus genomic sequence. The open reading frames predicted by GlimmerM showed a high amino acid sequence similarity with the other fungal phospholipid biosynthetic genes and well‐conserved functional domains. The obtained results also demonstrated that the reconstructed pathway of A. fumigatus in phospholipid biosynthesis was very similar to that of other fungi such as Saccharomyces cerevisiae, Schizosaccharomyces pombe, Candida albicans, and Neurospora crassa. Therefore it is postulated that the antifungal drugs targeted for the biosynthesis of phospholipids could also be effective against A. fumigatus. 相似文献
986.
Young Sun Ro Sang Do Shin Kyoung Jun Song Joo Yeong Kim Eui Jung Lee Yu Jin Lee Ki Ok Ahn Ki Jeong Hong Cardiac Arrest Pursuit Trial with Unique Registry Epidemiologic Surveillance investigators 《PloS one》2016,11(4)
BackgroundThis study aimed to determine the risk of diabetes mellitus (DM) on incidence of out-of-hospital cardiac arrest (OHCA) and to investigate whether difference in effects of DM between therapeutic methods was observed.MethodsThis study was a case-control study using the Cardiac Arrest Pursuit Trial with Unique Registration and Epidemiologic Surveillance (CAPTURES) project database and 2013 Korean Community Health Survey (CHS). Cases were defined as EMS-treated adult (18 year old and older) OHCA patients with presumed cardiac etiology collected at 27 emergency departments from January to December 2014. OHCA patients whose arrest occurred at nursing homes or clinics and cases with unknown information on DM were excluded. Four controls were matched to one case with strata including age, gender, and county from the Korean CHS database. Multivariable conditional logistic regression analysis was conducted to estimate the risk of DM and treatment modality on incidence of OHCA.ResultsTotal 1,386 OHCA patients and 5,544 community-based controls were analyzed. A total of 370 (26.7%) among cases and 860 (15.5%) among controls were diagnosed with DM. DM was associated with increasing risk of OHCA (AOR: 1.92 (1.65–2.24)). By DM treatment modality comparing with non-DM group, AOR (95% CI) was the highest in non-pharmacotherapy only group (4.65 (2.00–10.84)), followed by no treatment group (4.17 (2.91–5.96)), insulin group (2.69 (1.82–3.96)), and oral hypoglycemic agent group (1.55 (1.31–1.85)).ConclusionDM increased the risk of OHCA, which was the highest in the non-pharmacotherapy group and decreased in magnitude with pharmacotherapy. 相似文献
987.
The aim of this research was to study when and how the stationary process of gait begins when walking starts from upright posture. The subject initially stood up on a large force plate, then walked. Three conditions of speed (slow, normal, fast) were examined. Five subjects participated in the experiment. A total of 105 trials were performed. The results show that, at the end of the first step, the progression velocity of the center of gravity is not significantly different from the mean progression velocity of gait during the second step of gait and that the time necessary to reach steady state gait from initial posture phase is constant. Furthermore, the frequency of the first step, when compared to published values of the steady state gait frequency, is not significantly different from these frequencies.
It can be concluded that the aim of the gait initiation process is to place the subject in steady-state gait within the first step, in an invariant time which is dependent only on the body segment parameters of each subject. 相似文献
988.
The increasing prevalence of social networks provides researchers greater opportunities to evaluate and assess changes in public opinion and public sentiment towards issues of social consequence. Using trend and sentiment analysis is one method whereby researchers can identify changes in public perception that can be used to enhance the development of a social consciousness towards a specific public interest. The following study assessed Relative search volume (RSV) patterns for global warming (GW) and Climate change (CC) to determine public knowledge and awareness of these terms. In conjunction with this, the researchers looked at the sentiment connected to these terms in social media networks. It was found that there was a relationship between the awareness of the information and the amount of publicity generated around the terminology. Furthermore, the primary driver for the increase in awareness was an increase in publicity in either a positive or a negative light. Sentiment analysis further confirmed that the primary emotive connections to the words were derived from the original context in which the word was framed. Thus having awareness or knowledge of a topic is strongly related to its public exposure in the media, and the emotional context of this relationship is dependent on the context in which the relationship was originally established. This has value in fields like conservation, law enforcement, or other fields where the practice can and often does have two very strong emotive responses based on the context of the problems being examined. 相似文献
989.
990.
Sonia Do Carmo Jean-Claude Forest Yves Giguère André Masse Julie Lafond Eric Rassart 《Reproductive biology and endocrinology : RB&E》2009,7(1):92