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1.
Grass carp, Ctenopharyngodon idellus (Valenciennes, 1844), is an economically important species widely cultured in the world, but its genome research resources are largely lacking. The objectives of this study were to construct normalized cDNA libraries for efficient EST analysis, to generate ESTs from these libraries, and to identify EST-related molecular markers such as microsatellites and single nucleotide polymorphisms (SNPs) for genetic analysis of this species. A total of 6,269 ESTs were generated representing 4,815 unique sequences, from which 105 putative microsatellites and 5,228 SNPs were identified. These genome resources provide the material basis for future genetic and functional analyses in this species.  相似文献   
2.
Threeextrinsicpolypeptides,whicharelocatedontheinnersurfaceofthylakoidmembrane,playessentialrolesinmaintainingthephotosyntheticevolutionofoxygen.Theyaregenerallyrecognizedasliablecomponentsofthephotosyntheticapparatus,andcanbereleasedbyavarietyofphysic…  相似文献   
3.
4.
Two samples (YC7, YC27) of Nicotiana tabacum showing leaf curling, vein swelling and enations on undersides of leaves were collected in the Fujian Province of China in 2007. Virus isolates YC7‐1 and YC7‐2 (associated with betasatellite, YC7‐2β) were detected in both samples. The complete DNA‐A sequence of YC7‐1 (FJ869907) comprised 2741 nucleotides (nt). The complete DNA‐A (FJ869908) and betasatellite (FJ869909) sequence of YC7‐2 consisted of 2754 and 1344 nt, respectively. YC7‐1 had the highest nucleotide sequence identity (97.3%) with Papaya leaf curl Guangdong virus (PaLCuGuV‐[CN:Gd2:02], AJ558122). YC7‐2 had the highest sequence identity (90.1%) with Ageratum yellow vein virus (AYVV‐TW[TW:Tai:99], AF307861) and its betasatellite (96.5%) with Ageratum yellow vein betasatellite (AYVB‐[TW:CHu:02], AJ542495). These indicate that YC7‐1 and YC7‐2 are isolates of PaLCuGuV and AYVV, respectively. Symptoms including leaf curling, vein swelling and enations on undersides of leaves were observed in N. tabacum and N. glutinosa when infected by whiteflies with sample YC7 as the viral source under greenhouse conditions. PCR results showed that these infected plants contained both YC7‐1 and YC7‐2/YC7‐2β. To our knowledge, this is the first report of PaLCuGuV and AYVV/AYVB co‐infecting N. tabacum in China.  相似文献   
5.
Lu  Beibei  Kan  Caixia  Ke  Shanlin  Xu  Haiying  Ni  Yuan  Wang  Changshun  Shi  Daning 《Plasmonics (Norwell, Mass.)》2017,12(4):1183-1191
Plasmonics - Bimetallic nanoparticles have attracted increasing interest because of their unique optical, electronic, magnetic, and catalytic properties which are different from that of their...  相似文献   
6.
The development of artificial nucleases that hydrolyze DNA or RNA is of great interest in molecular biology, biotechnology, and medicine. We now report that a magnesium(II) complex of diethylenetriamine (Mg-dien) can effectively promote the double-stranded cleavage of plasmid DNA and the dideoxynucleotide dApdA under physiological conditions of pH and temperature. Experiments performed in the presence of hydrogen peroxide, radical scavengers, or under rigorously anaerobic conditions indicate that DNA cleavage mediated by Mg-dien occurs via a hydrolytic path. Mg-dien efficiently hydrolyzes supercoiled pBR322 DNA and the pseudo-first-order rate constant at 37 degrees C and pH 8.0 is estimated to be 1.60 h(-1). The dinucleotide dApdA hydrolysis, with Mg-dien at 170 microM, shows a rate enhancement factor of ca. 5 x 10(8). 1H and 31P(1H) NMR studies show that Mg-dien effectively hydrolyzes 5'-dAMP to give deoxyadenosine and inorganic phosphate. While Mg2+ has been found at the catalytic sites of many natural nucleases, Mg-dien appears to be the first synthetic Mg2+-containing system capable of hydrolyzing dideoxynucleotides and DNA and thus may provide a simple model system to assist mechanistic studies of naturally occurring nucleases.  相似文献   
7.
氮磷肥配施对冬小麦灌浆期光合参数及产量的影响   总被引:2,自引:0,他引:2  
在西北绿洲生态条件下, 实验设4个处理, 即165(N1)和225 kg·hm-2(N2)2个氮素(纯氮)水平及105(P1)和165 kg·hm-2(P2)2个磷素(P2O5)水平, 研究了氮磷肥配施对冬小麦(Triticum aestivum)品种临抗2号光合特性及产量的影响。结果表明, 低氮(165 kg·hm-2)处理组的净光合速率(Pn)、气孔导度(Gs)及蒸腾速率(Tr)日变化均呈双峰曲线, 有光合“午休”现象; 高氮(225 kg·hm-2)处理可减弱甚至使光合“午休”现象消失; 高磷(165 kg·hm-2)和低磷(105 kg·hm-2)处理对光合特性的影响差异不显著。N2P2具有最高的群体叶面积指数(LAI)、群体光合速率(CAP)、穗粒数、亩穗数、千粒重及产量, 且与N1P1和N1P2的差异均达显著水平, 与N2P1则无显著差异。但N2P2水分利用效率(WUE)低于N2P1, 显著高于N1P1和N1P2 (N1P1高于N1P2, 但无显著差异)。氮肥对光合“午休”的影响大于磷肥, 二者互作效应差异不显著。该实验条件下, 当N、P分别为225和105 kg·hm-2时有利于提高冬小麦的光合速率及产量。  相似文献   
8.
Traumatic spinal cord injury(SCI) is a major challenge in the clinic. In this study, we sought to examine the synergistic effects of linear ordered collagen scaffold(LOCS) and human placenta-derived mesenchymal stem cells(hPMSCs) when transplanted into completely transected beagle dogs. After 36 weeks observation, we found that LOCS+hPMSCs implants promoted better hindlimb locomotor recovery than was observed in the non-treatment(control) group and LOCS group. Histological analysis showed that the regenerated tissue after treatment was well integrated with the host tissue, and dramatically reduced the volume of cystic and chondroitin sulfate proteoglycans(CSPGs) expression. Furthermore, the LOCS+hPMSCs group also showed more neuron-specific βIII-tubulin(Tuj-1)-and NeuN-positive neurons in the lesion area, as well as axonal regeneration, remyelination and synapse formation in the lesion site. Additionally, dogs in the LOCS+hPMSCs group experienced enhanced sprouting of both ascending(CGRP-positive) sensory fibers and descending(5-HT-and TH-positive) motor fibers at the lesion area. All these data together suggested that the combined treatment had beneficial effects on neuronal regeneration and functional improvement in a canine complete transection model. Therefore, LOCS+hPMSCs implantation holds a great promise for bridging the nerve defect and may be clinically useful in the near future.  相似文献   
9.
Xu B  Wang S  Jiang Y  Yang L  Li P  Xie C  Xing J  Ke Z  Li J  Gai J  Yang G  Bao B  Liu Z 《Animal biotechnology》2010,21(4):217-225
Grass carp, Ctenopharyngodon idellus (Valenciennes, 1844), is an economically important species widely cultured in the world, but its genome research resources are largely lacking. The objectives of this study were to construct normalized cDNA libraries for efficient EST analysis, to generate ESTs from these libraries, and to identify EST-related molecular markers such as microsatellites and single nucleotide polymorphisms (SNPs) for genetic analysis of this species. A total of 6,269 ESTs were generated representing 4,815 unique sequences, from which 105 putative microsatellites and 5,228 SNPs were identified. These genome resources provide the material basis for future genetic and functional analyses in this species.  相似文献   
10.

Backgrounds

Matrix metalloproteinase 2 (MMP-2) plays a crucial role in the progression of breast cancer (BC). The prognostic role of MMP-2 expression in BC patients has been widely reported, but the results were inconsistent. Thus, a meta-analysis was conducted to gain a better insight into the impact of MMP-2 expression on survival and clinicopathological features of BC patients.

Methods

Identical search strategies were used to search relevant literatures in electronic databases update to August 1, 2014. Individual hazard ratios (HRs) and odds ratios (ORs) with their 95% confidence intervals (CIs) were extracted and pooled to evaluate the strength of the association between positive MMP-2 expression and survival results and clinicopathological features of BC patients. Begg’s tests, Egger’s tests and funnel plots were used to evaluate publication bias. Heterogeneity and sensitivity analysis were also assessed. All the work was completed using STATA.

Results

Pooled HRs and 95% CIs suggested that MMP-2 expression had an unfavorable impact on both OS (HR: 1.53, 95% CI: 1.29–1.82) and DFS/RFS/DDFS (HR: 1.41, 95% CI: 1.07–1.86) in BC patients. Furthermore, MMP-2 expression was significantly associated with lymph node metastasis (positive vs negative: OR 1.91, 95% CI 1.17–3.12).

Conclusion

In conclusion, positive MMP-2 expression might be a significant predictive factor for poor prognosis in patients with BC.  相似文献   
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