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991.
Somatic embryogenesis (SE) was successfully induced from mature zygotic embryos of seven families of Picea likiangensis (Franch.) Pritz after 20 weeks culture on initiation medium. Three basal media (one-half strength LM medium, one-half strength
LP medium and improved LP medium) with different concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D) and 6-benzyladenine
(6-BA) were tested but only one-half strength LM medium supplemented with 2,4-D and 6-BA was successful for the embryogenic
cultures (EC) initiation. The initiation frequencies of EC varied greatly from different families when culturing on the same
initiation medium. The highest frequency (41.3%) was induced from one of the families on one-half strength LM medium supplemented
with 3 mg L−1 2,4-D and 1.5 mg L−1 6-BA and 16.83% on average for seven families. EC were subcultured and proliferated on the same medium as the initiation
one every 10 days. 3 lines of EC induced from the same family were applied in maturation experiment. Cotyledonary somatic
embryos were observed after EC were transferred to maturation media of one-half strength LM medium containing 20-80 mg L−1 abscisic acid and 7.5% polyethylene glycol (PEG-4000). However, one-half strength LM medium supplemented with 40 mg L−1 or 60 mg L−1 ABA and 7.5% PEG gave the best maturation and the 3 lines showed different ability in maturation. Over 80% cotyledonary somatic
embryos germinated normally on DCR medium containing 0.2% activated carbon. The success on SE induction of the species has
provided an effective clonal propagation method for this important tree’s genetic improvement. 相似文献
992.
Tatiana Y Prudnikova Liudmila A Mostovich Natalia V Domanitskaya Tatiana V Pavlova Vladimir I Kashuba Eugene R Zabarovsky Elvira V Grigorieva 《Cancer cell international》2010,10(1):27
Background
D-glucuronyl C5-epimerase (GLCE) is one of the key enzymes in the biosynthesis of heparansulfate proteoglycans. Down-regulation of GLCE expression in human breast tumours suggests a possible involvement of the gene in carcinogenesis. In this study, an effect of GLCE ectopic expression on cell proliferation and viability of breast carcinoma cells MCF7 in vitro and its potential molecular mechanisms were investigated. 相似文献993.
Raf Brouns Robert Verkerk Tony Aerts Didier De Surgeloose Annick Wauters Simon Scharpé Peter P. De Deyn 《Neurochemical research》2010,35(9):1315-1322
Post-stroke inflammation may induce upregulation of the kynurenine (KYN) pathway for tryptophan (TRP) oxidation, resulting
in neuroprotective (kynurenic acid, KA) and neurotoxic metabolites (3-hydroxyanthranillic acid, 3-HAA). We investigated whether
activity of the kynurenine pathway in acute ischemic stroke is related to initial stroke severity, long-term stroke outcome
and the ischemia-induced inflammatory response. Plasma concentrations of TRP and its metabolites were measured in 149 stroke
patients at admission, at 24 h, at 72 h and at day 7 after stroke onset. We evaluated the relation between the KYN/TRP ratio,
the KA/3-HAA ratio and stroke severity, outcome and inflammatory parameters (C-reactive protein (CRP), erythrocyte sedimentation
rate (ESR) and neutrophil/lymphocyte ratio (NLR)). KYN/TRP but not KA/3-HAA correlated with the NIHSS score and with the infarct
volume. Patients with poor outcome had higher mean KYN/TRP ratios than patients with more favourable outcome. The KYN/TRP
ratio at admission correlated with CRP levels, ESR and NLR. The activity of the kynurenine pathway for tryptophan degradation
in acute ischemic stroke correlates with stroke severity and long-term stroke outcome. Tryptophan oxidation is related to
the stroke-induced inflammatory response. 相似文献
994.
Yan Li Yunshan Ning Yundan Wang Dandan Peng Yaodong Jiang Lili Zhang Min Long Jun Luo Ming Li 《BMC biotechnology》2010,10(1):84
Background
Urease B is an important virulence factor that is required for Helicobacter pylori to colonise the gastric mucosa. Mouse monoclonal antibodies (mAbs) that inhibit urease B enzymatic activity will be useful as vaccines for the prevention and treatment of H. pylori infection. Here, we produced murine mAbs against urease B that neutralize the enzyme's activity. We mapped their epitopes by phage display libraries and investigated the immunogenicity of the selected mimotopes in vivo. 相似文献995.
996.
Two amphipods, the hypogean Niphargus stygius and epigean Gammarus fossarum, were analyzed for fatty acid (FA) composition, electron transport system (ETS) activity and respiration (R) during a laboratory
fasting experiment. In agreement with ETS and R measurements (and the ETS/R ratio), the hypogean N. stygius utilized FA more slowly than the epigean G. fossarum. Inter-specific differences in the utilization of certain FA during fasting were also revealed. While N. stygius tended to preserve all of its FA during the experimental fasting period, G. fossarum showed a tendency to utilize MUFA (monounsaturated FA) and SAFA (saturated FA) and preferentially retain PUFA (polyunsaturated
FA). The significant correlations between ETS activity and composition of specific FA during fasting can be linked to R. During
the fasting, both ETS activity and respiration rate of G. fossarum decreased, however, ETS/R ratio increased. In contrast, N. stygius did not show significant changes in these parameters. This is the first report, which connects ETS activity with changes
in concentrations of specific FA during fasting. Such evolutionary adaptations of hypogean species enables them to better
survive chronically low and/or discontinuous food supplies compared to epigean species, which live in environments where food
shortages are much less frequent. 相似文献
997.
Danilo E Xavier Renata C Picão Raquel Girardello Lorena CC Fehlberg Ana C Gales 《BMC microbiology》2010,10(1):217
Background
Multi-drug efflux pumps have been increasingly recognized as a major component of resistance in P. aeruginosa. We have investigated the expression level of efflux systems among clinical isolates of P. aeruginosa, regardless of their antimicrobial susceptibility profile. 相似文献998.
999.
1000.
Bihao Cao Yaqing Lu Guoju Chen Jianjun Lei 《Plant Cell, Tissue and Organ Culture》2010,103(2):217-226
The translationally controlled tumor protein (TCTP) is an important component of the target of rapamycin (TOR) signaling pathway,
the major regulator of cell growth in animals and fungi. Despite its relevance, knowledge on plant TCTP homologs is still
limited. In the present study, the full-length BoTCTP cDNA was isolated from a cabbage (Brassica oleracea L.) cDNA library. The BoTCTP cDNA encodes a polypeptide of 168 amino acids and shared the highly conserved GTPase binding surface in all of the species
analyzed. Northern blotting analysis showed that BoTCTP was specifically expressed in the root and stem. Furthermore, the expression of BoTCTP could be obviously enhanced by stress stimuli, including high temperature and salt stresses, while no significant changes
in the BoTCTP expression were observed under ABA stress. Functional analysis of BoTCTP was performed by the silencing of BoTCTP using RNA interference (RNAi) and the BoTCTP RNAi plants exhibited reduced vegetative growth rate and decreased tolerance of the cold, high temperature, and salt stresses.
The reported results clearly suggest that the BoTCTP gene is involved in the regulation of both growth and stress response in cabbage. 相似文献