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941.
Raspor Martin Motyka Václav Ninković Slavica Malbeck Jiří Dobrev Petre I. Zdravković-Korać Snežana Simonović Ana Ćosić Tatjana Cingel Aleksandar Savić Jelena Zahajská Lenka Tadić Vojin Dragićević Ivana Č. 《Journal of Plant Growth Regulation》2021,40(1):37-47
Journal of Plant Growth Regulation - Over the last years, cytokinin deficiency has been studied in a variety of plant species, using transgenic expression of cytokinin oxidase/dehydrogenase genes... 相似文献
942.
Zhuo Shen Daode Ji Zhenzhen Yi Khaled A. S. Al‐Rasheid Xiaofeng Lin 《The Journal of eukaryotic microbiology》2017,64(2):266-277
The morphology, infraciliature, and silverline system of three peritrichous ciliates, Zoothamnium bucciniiformum sp. n., Zoothamnium florens sp. n., and Zoothamnium zhanjiangense sp. n., were investigated based on both living and silver‐stained specimens. Zoothamnium bucciniiformum sp. n., collected from coastal waters (salinity 30‰) off Zhanjiang, southern China, can be distinguished by the following characters: dichotomously branched stalk, peristomial lip with medial circumferential infolding, contractile vacuole apically positioned, 32–49 silverlines between the anterior end and the aboral trochal band, 15–26 between the aboral trochal band and the scopula; two kineties in peniculus 3, not parallel to each other. Zoothamnium florens sp. n., collected from a mangrove wetland (salinity 13‰) off Zhanjiang, is characterized by its large conical zooid, tuberculate peristomial lip, asymmetrical dichotomously branched colony, 59–81 silverlines between the anterior end and the aboral trochal band and 29–36 between the aboral trochal band and the scopula. Zoothamnium zhanjiangense, collected from a mangrove wetland (salinity about 9.5‰) off Zhanjiang, differs from its congeners by the alternately branched stalk, peristomial lip with medial circumferential infolding, 40–63 silverlines from the peristomial area to the aboral trochal band and 13–24 from the aboral trochal band to the scopula. The comparison and analysis of SSU rDNA sequences also support present identifications. 相似文献
943.
Jun YJ Min JH Ji da E Yoo JH Kim JH Lee HJ Jeong B Sohn YS 《Bioorganic & medicinal chemistry letters》2008,18(24):6410-6413
A novel water soluble and biodegradable cyclotriphosphazene-paclitaxel conjugate was prepared by reacting 2'-succinyl paclitaxel with cyclotriphosphazenes bearing equimolar glycyl-L-lysine and methoxy poly(ethylene glycol) as side groups. The macromolecular conjugate was found to self-assemble in aqueous solution to form stable micelles with a mean hydrodynamic diameter of 24.7 nm and a low critical micelle concentration of 10 mg/L. The present conjugate exhibited lower than free paclitaxel but reasonably high in vitro cytotoxicity against selected human tumor cells due to their hydrolytic degradation in PBS solution. 相似文献
944.
Spatial variation of species diversity across scales in an old-growth temperate forest of China 总被引:1,自引:0,他引:1
Xugao Wang Zhanqing Hao Ji Ye Jian Zhang Buhang Li Xiaolin Yao 《Ecological Research》2008,23(4):709-717
Species richness and abundance are the two most important diversity variables. Species abundance is additive when aggregated
across spatial scale, whereas species richness is non-additive. This study analyzes the effect of spatial scale and site on
species abundance and richness in a 25-ha temperate forest plot in the Changbai Mountains, northeastern China. The result
shows that species abundance and richness are not only dependent on spatial scales, but also dependent on site. Species abundance
responds linearly to changes of spatial scale with no intersection in different sites of the study area. However, although
species richness also increases with the increase of spatial scale, there are some intersections for the different sites,
suggesting that a species-rich site does not always have a high value if the spatial scale is changed. In all, with respect
to additive variables, it is relatively easy to extrapolate them from one spatial scale to another spatial scale, as they
and the spatial scale usually form a linear relationship. In contrast, non-additive variables are difficult to extrapolate
across spatial scales, because they often respond nonlinearly to spatial scale changes. In order to extrapolate these non-additive
variables across spatial scales, it is necessary to estimate the relationships between them and spatial scales. As a result,
extrapolation of information among spatial scales may be possible, but very difficult, especially for non-additive variables.
Because the 25-ha Changbai plot is very small compared to the extent of the world temperate forests, and the vegetation is
a relatively uniform type, more such studies in other ecosystems are needed before theories and generalization about scaling
effects can be formulated. 相似文献
945.
946.
Role of Arabidopsis CHL27 protein for photosynthesis, chloroplast development and gene expression profiling 总被引:1,自引:0,他引:1
Bang WY Jeong IS Kim DW Im CH Ji C Hwang SM Kim SW Son YS Jeong J Shiina T Bahk JD 《Plant & cell physiology》2008,49(9):1350-1363
In Chl biosynthesis, aerobic Mg-protoporphyrin IX monomethyl ester (MPE) cyclase is a key enzyme involved in the synthesis of protochlorophyllide a, and its membrane-bound component is known to be encoded by homologs of CHL27 in photosynthetic bacteria, green algae and plants. Here, we report that the Arabidopsis chl27-t knock-down mutant exhibits retarded growth and chloroplast developmental defects that are caused by damage to PSII reaction centers. The mutant contains a T-DNA insertion within the CHL27 promoter that dramatically reduces the CHL27 mRNA level. chl27-t mutant plants grew slowly with a pale green appearance, suggesting that they are defective in Chl biosynthesis. Chl fluorescence analysis showed significantly low photosynthetic activity in chl27-t mutants, indicating damage in their PSII reaction centers. The chl27-t mutation also conferred severe defects in chloroplast development, including the unstacking of thylakoid membranes. Microarray analysis of the chl27-t mutant showed repression of numerous nuclear genes involved in photosynthesis, including those encoding components of light-harvesting complex I (LHCI) and LHCII, and PSI and PSII, which accounts for the defects in photosynthetic activity and chloroplast development. In addition, the microarray data also revealed the significant repression of genes such as PORA and AtFRO6 for Chl biosynthesis and iron acquisition, respectively, and, furthermore, implied that there is cross-talk in the Chl biosynthetic pathway among the PORA, AtFRO6 and CHL27 proteins. 相似文献
947.
Joon Ha Park Choong Hyun Lee In Hye Kim Ji Hyeon Ahn Jeong-Hwi Cho Bing Chun Yan Jae-Chul Lee Tae Hun Lee Jeong Yeol Seo Jun Hwi Cho Moo-Ho Won Il-Jun Kang 《Neurochemical research》2013,38(12):2640-2649
Glucose is a main energy source for normal brain functions. Glucokinase (GK) plays an important role in glucose metabolism as a glucose sensor, and GK activity is modulated by glucokinase regulatory protein (GKRP). In this study, we examined the changes of GK and GKRP immunoreactivities in the gerbil hippocampus after 5 min of transient global cerebral ischemia. In the sham-operated-group, GK and GKRP immunoreactivities were easily detected in the pyramidal neurons of the stratum pyramidale of the hippocampus. GK and GKRP immunoreactivities in the pyramidal neurons were distinctively decreased in the hippocampal CA1 region (CA), not CA2/3, 3 days after ischemia–reperfusion (I–R). Five days after I–R, GK and GKRP immunoreactivities were hardly detected in the CA1, not CA2/3, pyramidal neurons; however, at this point in time, GK and GKRP immunoreactivities were newly expressed in astrocytes, not microglia, in the ischemic CA1. In brief, GK and GKRP immunoreactivities are changed in pyramidal neurons and newly expressed in astrocytes in the ischemic CA1 after transient cerebral ischemia. These indicate that changes of GK and GKRP expression may be related to the ischemia-induced neuronal damage/death. 相似文献
948.
A divergent external loop confers antagonistic activity on floral regulators FT and TFL1 总被引:24,自引:0,他引:24
Ahn JH Miller D Winter VJ Banfield MJ Lee JH Yoo SY Henz SR Brady RL Weigel D 《The EMBO journal》2006,25(3):605-614
949.
Samad Abdul Zhang Ji Chen Da Chen Xiaowen Tucker Melvin Liang Yanna 《Journal of industrial microbiology & biotechnology》2017,44(3):353-362
Journal of Industrial Microbiology & Biotechnology - To make the process of producing sophorolipids by Candida bombicola truly sustainable, we investigated production of these biosurfactants on... 相似文献
950.
Zuoxu Fan Tao Ji Shu Wan Yaoyao Wu Yu Zhu Feng Xiao Renya Zhan 《Cancer epidemiology》2013,37(1):39-45
Objective: The relationship between smoking and the development of meningioma has been investigated in several epidemiological studies. However, the results of these studies are inconsistent. We conducted a meta-analysis in order to identify any potential association. Methods: PubMed, the Cochrane Library, and EMBASE databases were searched to identify relevant articles that investigated the risk of meningioma following cigarette smoking. Two researchers evaluated study eligibility and extracted the data independently, and disagreements were resolved by discussion. The variables used to estimate the pooled risk of smoking in meningioma development were the multivariate-adjusted risk estimates presented in the literature. Results: Seven case–control and two cohort studies were included in this meta-analysis. The pooled estimated risks associated with ever smoking for meningioma were 1.02 (95% confidence interval (CI): 0.85–1.21) in the case–control studies, 0.93 (95% CI: 0.83–1.04) in the cohort studies and 0.95 (95% CI: 0.87–1.05, P = 0.32) in all studies when the cohort and case–control data were combined. Subgroup analyses suggested that the risk estimates were 1.49 (95% CI: 1.06–2.09, P = 0.02), 0.86 (95% CI: 0.65–1.13), 0.79 (95% CI: 0.50–1.25) and 0.84 (95% CI: 0.69–1.03) for men, women, current and past smoking respectively. Sensitivity analyses restricted to studies with different adjustments for confounders yielded similar results. No evidence of publication bias was observed. Conclusion: Our meta-analysis suggests that there is no association between ever smoking and the risk of meningioma. However, a small but significant risk elevation is present among men smokers. 相似文献