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991.
Zhuqin Zhang Zhiguo Zhao Bing Liu Dongguo Li Dandan Zhang Houzao Chen Depei Liu 《Quantitative Biology.》2013,1(2):140-5
The concept of “systems biology” is raised by Hood in 1999. It means studying all components with a systematic view. Systems biomedicine is the application of systems biology in medicine. It studies all components in a whole system and aims to reveal the patho-physiologic mechanisms of disease. In recent years, with the development of both theory and technology, systems biomedicine has become feasible and popular. In this review, we will talk about applications of some methods of omics in systems biomedicine, including genomics, metabolomics (proteomics, lipidomics, glycomics), and epigenomics. We will particularly talk about microbiomics and omics for common diseases, two fields which are developed rapidly recently. We also give some bioinformatics related methods and databases which are used in the field of systems biomedicine. At last, some examples that illustrate the whole biological system will be given, and development for systems biomedicine in China and the prospect for systems biomedicine will be talked about. 相似文献
992.
【目的】ABC(ATP-binding cassette)转运蛋白是一类重要的跨膜蛋白超家族,某些ABC转运蛋白基因在一些害虫的抗药性品系中表达显著提高。本研究旨在克隆禾谷缢管蚜 Rhopalosiphum padi ABC转运蛋白基因RhpaABCG9,RhpaABCG20和RhpaABCG23 cDNA全序列,分析这3个基因在该虫不同发育阶段和不同抗药性品系中的表达模式,为阐明ABC转运蛋白在禾谷缢管蚜抗药性中的作用和其他生理功能,以及深入分析该虫抗药性机理奠定基础。【方法】采用RT-PCR与RACE技术,克隆了基因cDNA全序列;利用实时荧光定量PCR技术,研究这3个基因在禾谷缢管蚜不同生长发育阶段和不同抗药性品系中的表达变化。【结果】获得了RhpaABCG9,RhpaABCG20和RhpaABCG23 3个基因cDNA全序列,其开放阅读框长度分别为2 103,2 436 和2 082 bp,分别编码700, 811和693个氨基酸。结构分析表明,3个蛋白均具有ABC转运蛋白家族典型的结构特征;系统进化分析结果显示,3个蛋白氨基酸序列分别与豌豆蚜Acyrthosiphon pisum各对应氨基酸的序列一致性最高。实时荧光定量PCR分析结果表明,这3个基因在禾谷缢管蚜不同发育时期均不同程度表达。RhpaABCG20在各个发育时期的表达变化差异不显著;RhpaABCG9表达量在4龄若蚜最高,在1龄若蚜最低;RhpaABCG23 表达量在3龄若蚜最高,1龄若蚜最低,其他阶段差异不显著。禾谷缢管蚜异丙威抗性品系中,RhpaABCG20表达量显著高于敏感品系,而RhpaABCG9和RhpaABCG23表达量均低于敏感品系,但差异不显著;禾谷缢管蚜吡虫啉抗性品系中,RhpaABCG20和RhpaABCG23表达量显著高于敏感品系,而RhpaABCG9表达上调不显著。【结论】RhpaABCG9,RhpaABCG20和RhpaABCG23基因可能参与禾谷缢管蚜体内农药的运输,并与禾谷缢管蚜的抗药性具有一定的关系。本研究结果为进一步深入分析禾谷缢管蚜的抗药性机制,以及该虫的抗药性治理与综合防治奠定了基础。 相似文献
993.
<正>自18世纪瑞典博物学家林奈奠定了植物科学命名的基础之后,国际上通用以拉丁语命名的植物学名(scientific name)作为学术交流的标准。除学名之外,植物的其他任何名称(包括所有非拉丁语名称)都叫作俗名(vernacular name)。在同一种语言的俗名中,又分普通名和别名(王锦秀和汤彦承,2005)。普通名是使用该语言的共同体普遍接受的名称,通常是综合性、权威性的植物志或植物名录中用作分类群正式名称的单一名称;而别名是普通名之外的其他所有俗名的统称,其应用常常存在局限性。 相似文献
994.
A species of the genus Dichocarpum (Ranunculaceae), Dlobatipetalum, is described as new from southeastern Yunnan Province, China. The morphological differences between it and its ally, Dmalipoense, are given. 相似文献
995.
996.
997.
Bing Liu Zhaohui Wan Baowei Sheng Yong Lin Tian Fu Qingdi Zeng Congcong Qi 《BMC pulmonary medicine》2017,17(1):214
Background
Previous studies show that overexpression of EMMPRIN involved in the malignant biological behavior of tumors. This investigation was to disclose the expression status of EMMPRIN in non-small cell lung cancer (NSCLC) and its clinical value for the diagnosis of NSCLC.Methods
The expression of EMMPRIN was examined using immunohistochemistry and enzyme-linked immunosorbent assay. The clinical value of EMMPRIN was evaluated by drawing a receiver operating characteristic (ROC) curve.Results
NSCLC tissues and serum exhibited higher expression levels of EMMPRIN than the normal control (p?<?0.05), and the expression of the EMMPRIN was significantly associated with lymphatic invasion and advanced stage of NSCLC (p?<?0.05). ROC curve suggested that the threshold level of serum EMMPRIN for distinguishing NSCLC from control group was 80.3 pg/mL, and displayed a sensitivity of 97.22% and a specificity of 95%. And higher EMMPRIN expression in serum and tissues appeared to be risk factors for NSCLC development (risk ratio =1.56 and 1.1).Conclusion
Overexpression of EMMPRIN was associated with lymphatic metastasis and advanced stage of NSCLC and test of serum EMMPRIN contributes to the NSCLC diagnosis.998.
Spinal cord injury (SCI) often leads to substantial disability due to loss of motor function and sensation below the lesion. Neural stem cells (NSCs) are a promising strategy for SCI repair. However, NSCs rarely differentiate into neurons; they mostly differentiate into astrocytes because of the adverse microenvironment present after SCI. We have shown that myelin-associated inhibitors (MAIs) inhibited neuronal differentiation of NSCs. Given that MAIs activate epidermal growth factor receptor (EGFR) signaling, we used a collagen scaffold-tethered anti-EGFR antibody to attenuate the inhibitory effects of MAIs and create a neuronal differentiation microenvironment for SCI repair. The collagen scaffold modified with anti-EGFR antibody prevented the inhibition of NSC neuronal differentiation by myelin. After transplantation into completely transected SCI animals, the scaffold-linked antibodies induced production of nascent neurons from endogenous and transplanted NSCs, which rebuilt the neuronal relay by forming connections with each other or host neurons to transmit electrophysiological signals and promote functional recovery. Thus, a scaffold-based strategy for rebuilding the neuronal differentiation microenvironment could be useful for SCI repair. 相似文献
999.
The effects of frozen storage (0–120 day) on the secondary structure and molecular chain conformation of hydrated gluten were investigated using Fourier transform infrared spectroscopy (FTIR) and atomic force microscopy (AFM). After frozen storage, no changes were observed in the secondary structure of the 60% hydrated gluten; spectra were consistent with a tight ordered structure with many interchain hydrogen bond interactions. For the dehydrated gluten, more complex changes took place: during frozen storage for up to 60 days, there were distinctive changes in the low-frequency region of the amide I band (1618–1633 cm?1) which were attributed to changes in the β-sheet structure. However, with the increase of frozen storage from 60 to 120 days, a band near 1614 cm?1 replaced that at 1659 cm?1 illustrate that the formation of protein aggregates during the long-time frozen storage, which along with the establishment of new intermolecular non-covalent bonds within the protein molecule or between two neighboring molecules. AFM images showed that the gluten chain formed a fibril-like branched network, and this network was weakened with increasing frozen storage time. 相似文献
1000.
本实验研究了3个向日葵品种在生长周期内茎、叶及茎叶混合样的水分、蛋白质和总黄酮含量的动态变化.结果表明:向日葵不同品种、不同生长期以及同一品种的不同部位的水分、蛋白质、总黄酮含量均存在差异.水分含量整体呈现下降趋势,且茎>茎叶混合>叶;蛋白质含量为叶>茎叶混合样>茎,其中高秆食用葵叶片中蛋白质含量为8.10g/100g... 相似文献