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91.
Jiang Li Peng Li-Li Cao Yu-Yao Thakur Kiran Hu Fei Tang Shun-Ming Wei Zhao-Jun 《Biological trace element research》2020,193(1):271-281
Biological Trace Element Research - The effects of selenium (Se) on the growth and reproduction of the Lepidoptera insect, the silkworm, Bombyx mori L were investigated. Initially, the silkworms... 相似文献
92.
93.
Wen-Jing Li Xin-Hui Chen Jia-Cheng Zeng Li-Li Duan 《Journal of biomolecular structure & dynamics》2020,38(14):4336-4343
Communicated by Ramaswamy H. Sarma 相似文献
94.
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
95.
为明确莱阳地区不同栽培模式下单植梨园、单植桃园、混植桃梨园的梨小食心虫Grapholitha molesta(Busck)发生规律,2009—2012年采用性诱芯法对以上果园梨小食心虫的发生规律进行探究并利用有效积温模型预测其发生代数。结果表明:梨小食心虫在莱阳地区一年可发生4代;第13代主要发生在桃园,发生时间为4—8月上旬,第4代主要发生在梨园,发生时间为8月中下旬或9月初,为害一直可持续到10月中旬。梨小食心虫在不同寄主上发生时间不同,除第一代发生比较整齐之外,其他世代发生时间不统一,尤其是梨园。单植梨园和单植桃园的梨小食心虫都能单独完成发育世代,但数量有差异。通过比较其差异显著性,单植桃园13代主要发生在桃园,发生时间为4—8月上旬,第4代主要发生在梨园,发生时间为8月中下旬或9月初,为害一直可持续到10月中旬。梨小食心虫在不同寄主上发生时间不同,除第一代发生比较整齐之外,其他世代发生时间不统一,尤其是梨园。单植梨园和单植桃园的梨小食心虫都能单独完成发育世代,但数量有差异。通过比较其差异显著性,单植桃园13代明显多于第4代,单植梨园第4代明显多于第13代明显多于第4代,单植梨园第4代明显多于第13代。 相似文献
96.
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
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98.
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99.