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81.
Due to its accuracy, sensitivity and high throughput, real time quantitative PCR (RT-qPCR) has been widely used in analysing gene expression. The quality of data from such analyses is affected by the quality of reference genes used. Expression stabilities for nine candidate reference genes widely used in soybean were evaluated under different stresses in this study. Our results showed that EF1A and ACT11 were the best under salinity stress, TUB4, TUA5 and EF1A were the best under drought stress, ACT11 and UKN2 were the best under dark treatment, and EF1B and UKN2 were the best under virus infection. EF1B and UKN2 were the top two genes which can be reliably used in all of the stress conditions assessed. 相似文献
82.
Jiqiang Zhang Ziru Niu Tianhua Li Yanqiang Wu Rui Xi Yuhua Li Guanghua Li Jialin Hou 《Phyton》2020,89(1):147-166
Considering the current low level of mechanization for domestic green
onion planting and the high labor intensity of artificial planting, a 2ZYX-2 green
onion ditching and transplanting machine, which can complete ditching, ridging,
transplanting, repression, soil covering and other operations, is designed in this
study. The Central Composite test design method was carried out with the speed
of the transplanting machine, the depth of the opener and the horizontal position
of the opener as the experimental factors and with the qualification ratio of
perpendicularity, the variation coefficient of the plant spacing and the
qualification ratio of the planting depth as the test index. Through the analysis of
the model interaction and response surface, the change laws that the influence
the machine’s forward speed, the depth of the opener and the horizontal position
of the opener were studied. The regression model was optimized by
Design-Expert 8.0.6 software, and the accuracy of the predicted results was
verified by experiments. The optimal working parameters showed that the
forward speed of the machine was 0.06 m/s, the depth of the opener was 102 mm,
and the horizontal position of the opener was 29 mm. Under conditions of
optimal working parameters, the qualification rate of the verticality was 86.83%,
the coefficient of variation for the plant spacing was 2.77, and the pass rate of
planting depth was 88.26%. The research related to the thesis can provide a
reference for the mechanized planting of green onion, which is of great
significance to the cost-effectiveness of the green onion industry. 相似文献
83.
Zhang Lin Tao Ye Zhao Suya Yin Xiaoyan Chen Junmei Wang Miao Cai Yingfan Niu Qiuhong 《Plant and Soil》2020,454(1-2):395-409
Plant and Soil - [Aims] To reveal the molecular mechanism of endophytic bacteria in Verticillium wilt-resistant cottons and deeply understand the interaction between soil and plants. [Methods]... 相似文献
84.
85.
锌作为一种结构、催化和信号的成分,在许多生理过程中起着关键的作用。它也是病原微生物生长所必需的,不但参与病原微生物代谢和各种毒力因子的调控,而且是病原微生物在宿主中感染和定殖所必需的。铜绿假单胞菌侵染宿主发挥毒力时,宿主会采取营养免疫的策略来限制体内环境中游离的锌离子浓度而抑制该病原菌的感染和定殖。反过来,铜绿假单胞菌则通过自身的锌离子摄取系统克服宿主的营养免疫防御。本综述重点介绍了铜绿假单胞菌中已知的3种锌离子摄取系统(ZnuABC摄取系统、HmtA摄取系统和CntRLMN摄取系统)和锌摄取调控蛋白Zur,同时分析了其他潜在的锌离子摄取途径,并进一步阐述了铜绿假单胞菌锌离子摄取系统在其侵染宿主发挥毒力时和抵御宿主营养免疫时发挥的重要作用。系统总结铜绿假单胞菌对锌离子的摄取过程,旨在为靶向锌离子摄取系统的新型抗铜绿假单胞菌药物的开发提供指导。 相似文献
86.
Zhongyu Liu Mengyu Xie Zhiqiang Yao Yulong Niu Youquan Bu Chunfang Gao 《Molecular neurobiology》2013,47(1):325-336
Glioma is one of the most common tumors of the central nervous system, and one of its main types is astrocytoma. Microarray technology has been widely used to explore the molecular mechanism of cancer. It is universally accepted that meta-analysis considerably improves the statistical robustness of results, particularly in clinical research. To obtain the maximum reliability, we used three different meta-analyses to integrate the four microarray datasets, GSE16011, GSE4290, GSE2223, and GSE19728 (local), and defined the common differentially expressed genes (DEGs) in astrocytomas compared with normal brain tissue. Four DEGs, PCNA, CDC2, CDK2 and CCNB2, which are components of the cell cycle pathway, were chosen for Real-Time Polymerase Chain Reaction (RT-PCR) and immunohistochemistry validation. PCNA is similar to the P53 gene and has been widely implicated in various cancers including gliomas. Therefore, the expression status of PCNA in our study was considered as a reference to test our whole experimental scheme, and the results indicate that our methodology is valid. Although a few studies have reported the overexpression of the CDC2, CDK2 and CCNB2 genes in glioma cell lines, we are the first to identify the statuses of these genes in human astrocytoma tissues at the mRNA and protein levels. The results of the gene validations strongly suggested that the genes play an important role in astrocytomas and could potentially be valuable in the diagnosis and treatment of astrocytoma. 相似文献
87.
88.
Aims
Our aims were to identify the primary factors involved in soil respiration (Rs) variability and the role that spectral vegetation indices played in Rs estimation in irrigated and rainfed agroecosystems during the growing season.Methods
We employed three vegetation indices [i.e., normalized difference vegetation index (NDVI), green edge chlorophyll index (CIgreen edge) and enhanced vegetation index (EVI)] derived from the Moderate-resolution Imaging Spectroradiometer (MODIS) surface reflectance product as approximations of crop gross primary production (GPP) for Rs estimation. Different statistical models were used to analyze the dependencies of Rs on soil temperature, soil water content and plant photosynthesis, and accuracy of these models were compared in the irrigated and rainfed agroecosystems.Results
The results demonstrated that a model based only on abiotic factors (e.g., soil temperature and soil water content) failed to describe part of the growing-season variability in Rs. Residual analysis indicated that Rs was influenced by a short-term gross primary production (GPP) and a longer-term (≥3 days) accumulated GPP in the irrigated and rainfed agroecosystems. Therefore, photosynthesis dependency of Rs should be included in the Rs model to describe the growing-season dynamics of Rs. Among the three VIs, CIgreen edge showed generally better correlations with GPP at different cumulative times and canopy green leaf area index than EVI and NDVI. Adding the CIgreen edge into the model considering only soil temperature and soil water content significantly improved the simulation accuracy of Rs.Conclusions
Our results suggest that spectral vegetation index from remote sensing could be used to estimate Rs, which will be helpful for the development of a future Rs model over a large spatial scale. 相似文献89.
90.
Zhong-Wei Liu Xiao-Lin Niu Kun-Lun Chen Yu-Jie Xing Xuan Wang Chuan Qiu Deng-Feng Gao 《Biological trace element research》2013,153(1-3):220-228
The possible mechanism of adriamycin (ADR) and/or selenium (Se) deficiency-induced cardiac dysfunction, and cardioprotective effects of Se against ADR-induced cardiac toxicity were investigated in this study. Cardiac function was evaluated by plasma brain natriuretic peptide level and echocardiographic and hemodynamic parameters. Cardiac glutathione peroxidase (GPx) activity was assessed spectrophotometrically. Expression of ATP-sensitive potassium channels (KATP) subunits—SUR2A and Kir6.2—were examined by real-time PCR and Western blotting. The results showed that cardiac function and cardiac GPx activity decreased remarkably after administration of ADR or Se deficiency; more dramatic impairment of cardiac function and cardiac GPx activity were observed after co-administration of ADR and Se deficiency. Mechanically, it is novel for us to find down-regulation of KATP subunits gene expression in cardiac tissue after administration of ADR or Se deficiency, and more significant inhibition of cardiac KATP gene expression was identified after co-administration of ADR and Se deficiency. Furthermore, cardiac toxicity of ADR was found alleviated by Se supplementation, accompanied by restoring of cardiac GPx activity and cardiac KATP gene expression. These results indicate that decreased expression of cardiac KATP is involved in adriamycin and/or Se deficiency-induced cardiac dysfunction; Se deficiency exacerbates adriamycin-induced cardiac dysfunction by future inhibition of KATP expression; Se supplementation seems to protect against adriamycin-induced cardiac dysfunction via restoring KATP expression, showing potential clinical application in cancer chemotherapy. 相似文献