排序方式: 共有42条查询结果,搜索用时 15 毫秒
1.
AV Shevchenko IG Budzanivska TP Shevchenko VP Polischuk D Spaar 《Archives Of Phytopathology And Plant Protection》2013,46(2):139-146
The work was focused on the investigation of possible dependencies between the development of viral infection in plants and the presence of high heavy metal concentrations in soil. Field experiments have been conducted in order to study the development of systemic tobacco mosaic virus (TMV) infection in Lycopersicon esculentum L. cv. Miliana plants under effect of separate salts of heavy metals Cu, Zn and Pb deposited in soil. As it is shown, simultaneous effect of viral infection and heavy metals in tenfold maximum permissible concentration leads to decrease of total chlorophyll content in experiment plants mainly due to the degradation of chlorophyll a. The reduction of chlorophyll concentration under the combined influence of both stress factors was more serious comparing to the separate effect of every single factor. Plants' treatment with toxic concentrations of lead and zinc leaded to slight delay in the development of systemic TMV infection together with more than twofold increase of virus content in plants that may be an evidence of synergism between these heavy metal's and virus' effects. Contrary, copper although decreased total chlorophyll content but showed protective properties and significantly reduced amount of virus in plants. 相似文献
2.
Zheng Ma Yalin Bian Xuping Shentu Xiaoping Yu 《Applied microbiology and biotechnology》2013,97(9):4055-4064
1,3-propanediol (1,3-PDO) is one of the most important industrial chemicals due to its highly desired properties and its wide applications as a key component of the emerging polymer industry. Biotechnology route has been one of the most interesting methods for 1,3-PDO production, whereas, the dha genes were essential to 1,3-PDO biosynthesis. In this study, we cloned and placed the dha cassettes under the control of a glyceraldehyde 3-phosphate dehydrogenase gene promoter pGAP and homologous ZrFPS1 gene promoter pZrfps1; these two promoters were further integrated into the chromosome of Z. rouxii JL2011 to generate recombinant strain JL2011-GZ and JL2011-ZZ, respectively. The results showed that the two strains could produce 1,3-PDO from glucose with a final yield of 6.9 and 10.3 g/l, respectively. The engineered strain JL2011-ZZ showed a 2.3- and 1.5-fold increase in the specific activities and final concentration of 1,3-PDO, respectively, with respect to JL2011-GZ. Batch fermentation with aerobic/micro-aerobic combined strategy of JL2011-ZZ resulted a titer of 17.1 g/l and a yield from glucose of 8.6 %. These results demonstrated that JL2011-ZZ would be a potential strain for 1,3-PDO production from glucose. 相似文献
3.
We describe an efficient method for partial complementary shape matching for use in rigid protein-protein docking. The local shape features of a protein are represented using boolean data structures called Context Shapes. The relative orientations of the receptor and ligand surfaces are searched using precalculated lookup tables. Energetic quantities are derived from shape complementarity and buried surface area computations, using efficient boolean operations. Preliminary results indicate that our context shapes approach outperforms state-of-the-art geometric shape-based rigid-docking algorithms. 相似文献
4.
Zheng Ma Jinxiu Liu Xiaozhen Lin Xuping Shentu Yalin Bian Xiaoping Yu 《Folia microbiologica》2014,59(2):93-97
Toyocamycin exhibits effective biological activities for use against plant pathogenic fungi thanks to its structural similarity to nucleoside. It has been recognized as a promising agricultural antibiotic utilized in controlling the occurrence of plant diseases. In our previous study, a strain that was isolated was identified and designated as Streptomyces diastatochromogenes whose major secondary metabolite was toyocamycin, but the production was largely limited. Protoplast transformation is a useful technique in the improvement of streptomycete. In this study, we optimized some key factors necessary for protoplast formation, regeneration, and transformation of S. diastatochromogenes. When mycelium was cultivated in CP medium with 1 % glycine, harvested at 48 h old, and then treated with 3 mg lysozyme/mL in P buffer for 1 h, the greatest regeneration frequency (42.5 %) of protoplasts was obtained. By using 1?×?109/mL protoplasts with polyethylene glycol 1000 at a concentration of 30 % (w/v), the best performance of protoplast transformation efficiency was 4.8?×?103/μg DNA transformants. 相似文献
5.
In some clinical development programs, there are potential biomarkers with promising but uncertain predictive effect, while the probability of success in the overall population cannot be readily dismissed. It is risky to focus only on the overall population, or just the biomarker subpopulation. In 2009, Chen and Beckman proposed a Bayesian decision framework to optimize the type I error rate (alpha) allocation in a Phase III clinical study with possible predictive subset effect. The utilization of internal data in this framework is of particular interest because it provides an opportunity to mitigate the potential risk of misspecified study assumptions using an auto-adaptive strategy. In this paper, we examine this auto-adaptive strategy in detail through extensive numerical case studies and provide guidance on the appropriate use of partial current trial (internal) data in this data-driven optimization framework. We show that internal data can be used to inform the alpha allocation to hypothesis testing in the overall population and the subgroup. The resulting adaptive testing strategy is robust with respect to the uncertainty in the predictive subgroup effect and biomarker prevalence. 相似文献
6.
Background
We conducted this meta-analysis to compare the outcomes of coaxial microincision cataract surgery (C-MICS) and standard coaxial small incision cataract surgery (C-SICS).Methods
The outcomes of randomized controlled trials (RCTs) reporting C-MICS and C-SICS were collected from PubMed, Web of Science, and The Cochrane Library in May 2015. The final meta-analysis was conducted on the following intraoperative and postoperative outcomes: ultrasound time (UST), effective phacoemulsification time (EPT), balanced salt solution use (BSS use), cumulative dissipated energy (CDE), mean surgery time, endothelial cell loss percentage (ECL%), best corrected visual acuity (BCVA), increased central corneal thickness (CCT), laser flare photometry values and surgically induced astigmatism (SIA).Results
A total of 15 RCTs, involving 1136 eyes, were included in the final meta-analysis. No significant between-group differences were detected in EPT, BSS use, CDE, BCVA, laser flare photometry values or increased CCT. However, the C-MICS group showed less SIA (at postoperative day 7: p<0.01; at postoperative day 30 or more: p<0.01) and greater ECL% (at postoperative day 60 or more: p<0.01), whereas the C-SICS group required a shorter UST (p<0.01).Conclusions
The present meta-analysis suggested that the C-MICS technique was more advantageous than C-SICS in terms of SIA, but C-MICS required a longer UST and induced a higher ECL%. Further studies should be done to confirm our results. 相似文献7.
Kaiming Guo Wenting Huang Kun Chen Pengkai Huang Wenshuo Peng Ruiqing Shi Tao He Mulan Zhang Hao Wang Jian Hu Xinshi Wang Yangping Shentu Huiqin Xu Li Lin 《Aging cell》2023,22(9):e13937
Alzheimer's disease (AD) is characterized with senile plaques formed by Aβ deposition, and neurofibrillary tangles composed of hyperphosphorylated tau protein, which ultimately lead to cognitive impairment. Despite the heavy economic and life burdens faced by the patients with AD, effective treatments are still lacking. Previous studies have reported the neuroprotective effects of FGF10 in CNS diseases, but its role in AD remains unclear. In this study, we demonstrated that FGF10 levels were reduced in the serum of AD patients, as well as in the brains of 3xTg-AD mice and APPswe-transfected HT22 cells, suggesting a close relationship between FGF10 and AD. Further investigations revealed that intranasal delivery of FGF10 improved cognitive functions in 3xTg-AD mice. Additionally, FGF10 treatment reduced tau hyperphosphorylation and neuronal apoptosis, thereby mitigating neuronal cell damage and synaptic deficits in the cortex and hippocampus of 3xTg-AD mice, as well as APPswe-transfected HT22 cells. Furthermore, we evaluated the therapeutic potential of FGF10 gene delivery for treating AD symptoms and pathologies. Tail vein delivery of the FGF10 gene using AAV9 improved cognitive and neuronal functions in 3xTg-AD mice. Similarly, endogenous FGF10 overexpression ameliorated tau hyperphosphorylation and neuronal apoptosis in the cortex and hippocampus of 3xTg-AD mice. Importantly, we confirmed that the FGFR2/PI3K/AKT signaling pathway was activated following intranasal FGF10 delivery and AAV9-mediated FGF10 gene delivery in 3xTg-AD mice and APPswe-transfected HT22 cells. Knockdown of FGFR2 attenuated the protective effect of FGF10. Collectively, these findings suggest that intranasal delivery of FGF10 and AAV9-mediated FGF10 gene delivery could be a promising disease-modifying therapy for AD. 相似文献
8.
9.
A highly conserved nuclear gene for low-level phylogenetics: elongation factor-1 alpha recovers morphology-based tree for heliothine moths 总被引:6,自引:2,他引:6
Cho S; Mitchell A; Regier JC; Mitter C; Poole RW; Friedlander TP; Zhao S 《Molecular biology and evolution》1995,12(4):650-656
Molecular systematists need increased access to nuclear genes. Highly
conserved, low copy number protein-encoding nuclear genes have attractive
features for phylogenetic inference but have heretofore been applied mostly
to very ancient divergences. By virtue of their synonymous substitutions,
such genes should contain a wealth of information about lower-level
taxonomic relationships as well, with the advantage that amino acid
conservatism makes both alignment and primer definition straightforward. We
tested this postulate for the elongation factor-1 alpha (EF-1 alpha) gene
in the noctuid moth subfamily Heliothinae, which has probably diversified
since the middle Tertiary. We sequenced 1,240 bp in 18 taxa representing
heliothine groupings strongly supported by previous morphological and
allozyme studies. The single most parsimonious gene tree and the
neighbor-joining tree for all nucleotides show almost complete concordance
with the morphological tree. Homoplasy and pairwise divergence levels are
low, transition/transversion ratios are high, and phylogenetic information
is spread evenly across gene regions. The EF-1 alpha gene and presumably
other highly conserved genes hold much promise for phylogenetics of
Tertiary age eukaryote groups.
相似文献