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植物干旱胁迫响应机制研究进展 被引量:57
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作者 王凯悦 陈芳泉 黄五星 《中国农业科技导报》 CAS CSCD 北大核心 2019年第2期19-25,共7页
干旱是限制植物生长的重要因素,会诱导植物产生渗透失衡、膜系统损伤、呼吸与光合速率降低等不良反应,不仅妨碍植物各阶段的生长代谢,还影响农作物的高质高产。在与外部环境的互作过程中,植物会产生干旱响应,如通过根系和叶片结构、代... 干旱是限制植物生长的重要因素,会诱导植物产生渗透失衡、膜系统损伤、呼吸与光合速率降低等不良反应,不仅妨碍植物各阶段的生长代谢,还影响农作物的高质高产。在与外部环境的互作过程中,植物会产生干旱响应,如通过根系和叶片结构、代谢物质成分的改变以及抗旱基因的表达来抵御干旱胁迫。从表型水平、生理水平和分子水平阐述了植物干旱胁迫响应的研究进展。其中,植物表型水平的干旱胁迫响应主要体现在根系和叶片的结构改变,而植物生理水平的干旱胁迫响应主要体现在光合作用、渗透调节代谢、抗氧化代谢和激素物质等方面,详细阐述了植物干旱胁迫响应的分子机制及参与其中的调节基因和功能基因,对研究中存在的问题进行了讨论,展望了植物干旱胁迫响应的研究前景。 展开更多
关键词 干旱 表型 生理 分子 基因工程
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Hydrogen Peroxide in Plants:a Versatile Molecule of the Reactive Oxygen Species Network 被引量:54
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作者 Li-Juan Quan Bo Zhang Wei-Wei Shi Hong-Yu Li 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2008年第1期2-18,共17页
Plants often face the challenge of severe environmental conditions, which include various biotic and abiotic stresses that exert adverse effects on plant growth and development. During evolution, plants have evolved c... Plants often face the challenge of severe environmental conditions, which include various biotic and abiotic stresses that exert adverse effects on plant growth and development. During evolution, plants have evolved complex regulatory mechanisms to adapt to various environmental stressors. One of the consequences of stress is an increase in the cellular concentration of reactive oxygen species (ROS), which are subsequently converted to hydrogen peroxide (H2O2). Even under normal conditions, higher plants produce ROS during metabolic processes. Excess concentrations of ROS result in oxidative damage to or the apoptotic death of cells. Development of an antioxidant defense system in plants protects them against oxidative stress damage. These ROS and, more particularly, H2O2, play versatile roles in normal plant physiological processes and in resistance to stresses. Recently, H2O2 has been regarded as a signaling molecule and regulator of the expression of some genes in cells. This review describes various aspects of H2O2 function, generation and scavenging, gene regulation and cross-links with other physiological molecules during plant growth, development and resistance responses. 展开更多
关键词 antioxidant system gene regulation hydrogen peroxide (H2O2) reactive oxygen species (ROS) signaling molecule.
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生物色谱技术分离、鉴定和筛选中药活性成分 被引量:25
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作者 邹汉法 汪海林 《世界科学技术》 2000年第2期9-13,54,共5页
本文认为用生物色谱技术研究生命科学是一个颇具魅力的新方向,也为中药现代化研究与生产提供了全新的技术和手段,因而有着广阔美好的前景。文中介绍了这一方法的现状、发展趋势、基本原理及其发展思路和策略。
关键词 中药活性成分 生物色谱技术 分离 鉴定 筛选
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Knockdown of CD146 reduces the migration and proliferation of human endothelial cells 被引量:34
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作者 Yanyong Kang Fengcai Wang +3 位作者 Jing Feng Dongling Yang Xu Yang Xiyun Yan 《Cell Research》 SCIE CAS CSCD 2006年第3期313-318,共6页
Our previous study has demonstrated that CD 146 molecule is a biomarker on vascular endothelium, which is involved in angiogenesis and tumor growth. However the mechanism behind is not clear. Here we have for the firs... Our previous study has demonstrated that CD 146 molecule is a biomarker on vascular endothelium, which is involved in angiogenesis and tumor growth. However the mechanism behind is not clear. Here we have for the first time developed a novel CD146 blockade system using CD146 siRNA to study its function on endothelial cells. Our data showed that CD146 siRNA specifically blocked the expression of CD146 on both mRNA and protein levels, leading to the significant suppression of HUVEC proliferation, adhesion and migration. These results demonstrate that CD146 plays a key role in vascular endothelial cell activity and angiogenesis, and CD146 siRNA can be used as a new inhibitor for anti-angiogenesis therapy. 展开更多
关键词 small interfering RNA adhesion molecule CD146 vascular endothelial cell
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Growth factor receptors and related signalling pathways as targets for novel treatment strategies of hepatocellular cancer 被引量:33
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作者 Michael Hpfner Detlef Schuppan Hans Scherübl 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第1期1-14,共14页
Growth factors and their corresponding receptors are commonly overexpressed and/or dysregulated in many cancers including hepatocellular cancer (HCC). Clinical trials indicate that growth factor receptors and their ... Growth factors and their corresponding receptors are commonly overexpressed and/or dysregulated in many cancers including hepatocellular cancer (HCC). Clinical trials indicate that growth factor receptors and their related signalling pathways play important roles in HCC cancer etiology and progression, thus providing rational targets for innovative cancer therapies. A number of strategies including monoclonal antibodies, tyrosine kinase inhibitors ("small molecule inhibitors") and antisense oligonucleotides have already been evaluated for their potency to inhibit the activity and downstream signalling cascades of these receptors in HCC. First clinical trials have also shown that multi-kinase inhibition is an effective novel treatment strategy in HCC. In this respect sorafenib, an inhibitor of Raf-, VEGF- and PDGF-signalling, is the first multi-kinase inhibitor that has been approved by the FDA for the treatment of advanced HCC. Moreover, the serine-threonine kinase of mammalian target of rapamycin (mTOR) upon which the signalling of several growth factor receptors converge plays a central role in cancer cell proliferation, roTOR inhibition of HCC is currently also being studied in preclinical trials. As HCCs represent hypervascularized neoplasms, inhibition of tumour vessel formation via interfering with the VEGF/VEGFR system is another promising approach in HCC treatment. This review will summarize the current status of the various growth factor receptor-based treatment strategies and in view of the multitude of novel targeted approaches, the rationale for combination therapies for advanced HCC treatment will also be taken into account. 展开更多
关键词 Growth factor receptor Hepatocellular cancer Small molecule inhibitor Monoclonal antibody Innovative cancer treatment SORAFENIB BEVACIZUMAB ERLOTINIB
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Small molecules targeting the innate immune cGAS-STING-TBK1 signaling pathway 被引量:29
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作者 Chunyong Ding Zilan Song +2 位作者 Ancheng Shen Tingting Chen Ao Zhang 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2020年第12期2272-2298,共27页
Multiple cancer immunotherapies including chimeric antigen receptor T cell and immune checkpoint inhibitors(ICIs)have been successfully developed to treat various cancers by motivating the adaptive anti-tumor immunity... Multiple cancer immunotherapies including chimeric antigen receptor T cell and immune checkpoint inhibitors(ICIs)have been successfully developed to treat various cancers by motivating the adaptive anti-tumor immunity.Particularly,the checkpoint blockade approach has achieved great clinic success as evidenced by several U.S.Food and Drug Administration(FDA)-approved antiprogrammed death receptor 1/ligand 1 or anti-cytotoxic T lymphocyte associated protein 4 antibodies.However,the majority of cancers have low clinical response rates to these ICIs due to poor tumor immunogenicity.Indeed,the cyclic guanosine monophosphate-adenosine monophosphate synthase-stimulator of interferon genes-TANK-binding kinase 1(cGAS-STING-TBK1)axis is now appreciated as the major signaling pathway in innate immune response across different species.Aberrant signaling of this pathway has been closely linked to multiple diseases,including auto-inflammation,virus infection and cancers.In this perspective,we provide an updated review on the latest progress on the development of small molecule modulators targeting the cGAS-STING-TBK1 signaling pathway and their preclinical and clinical use as a new immune stimulatory therapy.Meanwhile,highlights on the clinical candidates,limitations and challenges,as well as future directions in this field are also discussed.Further,small molecule inhibitors targeting this signaling axis and their potential therapeutic use for various indications are discussed as well. 展开更多
关键词 mmunotherapy ANTI-TUMOR cGAS STING TBK1 Small molecule modulators
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Degradation of proteins by PROTACs and other strategies 被引量:28
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作者 Yang Wang Xueyang Jiang +2 位作者 Feng Feng Wenyuan Liu Haopeng Sun 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2020年第2期207-238,共32页
Abnormal protein expression or activities are associated with many diseases,especially cancer.Therefore,down-regulating the proteins involved in cancer cell survival proved to be an effective strategy for cancer treat... Abnormal protein expression or activities are associated with many diseases,especially cancer.Therefore,down-regulating the proteins involved in cancer cell survival proved to be an effective strategy for cancer treatment—a number of drugs based on proteolysis-targeting chimaera(PROTAC)mechanism have demonstrated clinical efficacy.Recent progress in the PROTAC strategy includes identification of the structure of the first ternary eutectic complex,extra-terminal domain-4-PROTAC-VonHippel-Lindau(BRD4-PROTAC-VHL),and PROTAC ARV-110 has entered clinical trials for the treatment of prostate cancer in 2019.These discoveries strongly proved the value of the PROTAC strategy.In this review,we summarize recent meaningful research of PROTACs,including the molecular design and optimization strategy as well as clinical application of candidate molecules.We hope to provide useful insights for rational design of PROTACs. 展开更多
关键词 PROTEIN DEGRADATION PROTAC UBIQUITIN-PROTEASOME system E3 UBIQUITIN LIGASE Target PROTEIN Heterobifunctional molecule
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脱色剂与活性染料的分子间相互作用 被引量:14
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作者 余颖 庄源益 +3 位作者 辛宝平 邹其猛 满悦芝 李莹 《南开大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第3期140-145,共6页
以聚丙烯腈(PAN)和双氰胺(DCD)为原料,合成了新型脱色剂.用IR、1 H NMR和13C NMR等方法对其结构进行了表征,探讨了脱色剂溶解度随pH 值变化的规律,研究了脱色剂对活性染料的絮凝脱色的性能.结果表明,脱... 以聚丙烯腈(PAN)和双氰胺(DCD)为原料,合成了新型脱色剂.用IR、1 H NMR和13C NMR等方法对其结构进行了表征,探讨了脱色剂溶解度随pH 值变化的规律,研究了脱色剂对活性染料的絮凝脱色的性能.结果表明,脱色剂是侧链带有多种极性基团的聚合物;它在酸性条件下溶解度较小,碱性条件下溶解度较大;脱色剂对活性染料的脱色是有效的.在絮凝脱色研究基础上,用IR分析以及平衡渗析实验探讨了脱色剂与多种染料的相互作用.实验结果表明,脱色剂的絮凝效果在酸性条件下显著.相互作用研究显示,脱色剂分子侧链的氨基与活性染料的磺酸基发生了键合作用.脱色剂与蒽醌型活性染料的结合存在特殊的温度依赖性,结合程度在25℃最大;脱色剂与活性染料分子间除了极性基团间相互作用外,还存在疏水相互作用. 展开更多
关键词 脱色剂 活性染料 相互作用 含染料废水 废水处理
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Negative Association of Circulating MicroRNA-126 with High-sensitive C-reactive Protein and Vascular Cell Adhesion Molecule-1 in Patients with Coronary Artery Disease Following Percutaneous Coronary Intervention 被引量:24
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作者 Jun-Nan Wang You-You Yan +3 位作者 Zi-Yuan Guo Ya-Juan Jiang Lu-Lu Liu Bin Liu 《Chinese Medical Journal》 SCIE CAS CSCD 2016年第23期2786-2791,共6页
Background: Percutaneous coronary intervention (PCI) causes endothelial damage, resulting in an inflammatory response with elevation of markers such as high-sensitive C-reactive protein (hs-CRP) and vascular cell... Background: Percutaneous coronary intervention (PCI) causes endothelial damage, resulting in an inflammatory response with elevation of markers such as high-sensitive C-reactive protein (hs-CRP) and vascular cell adhesion molecule-1(VCAM-1), which are associated with restenosis after PCI. Evidence suggests that microRNA-126 (miR-126) plays an important role in vascular inflammation, but its correlation with PCl-mediated inflammation has not been investigated. In this study, we investigated the effect of PCI on circulating miR-126 and inflammation markers such as hs-CRP and VCAM-1. Methods: We enrolled 130 patients with coronary artery disease (CAD) in the Second Hospital of Jilin University from October 2015 to December 2015. Among them, 82 patients with CAD, defined as at least one major epicardial vessel with 〉70% stenosis who planned to undergo PCI, were divided into acute coronary syndrome (ACS) group (46 patients) and stable angina (SA) group (36 patients). Forty-eight patients confirmed by coronary angiography without PCI were used as controls. The plasmas of all patients were collected prior to PCI and at 30 min, 24 h, and 72 h after PCI. The plasma VCAM-1 and hs-CRP were detected by enzyme-linked immunosorbent assay, and the miR-126 was evaluated by quantitative reverse transcription-polymerase chain reaction. Results: Plasma concentrations of hs-CRP and VCAM-I in patients with either ACS (n = 46) or SA (n = 36) were significantly higher than in controls (n = 48) (P 〈 0.01) prior to PCI, and increased further at 24 h and 72 h after PCI, compared with prior PCI. Moreover, VCAM-1 was positively correlated with balloon time and pressure. In contrast, the plasma concentration of miR-126 was significantly lower in patients with CAD than in controls, and further decreased with time post-PCl. A negative correlation was observed between miR-126 and hs-CRP and VCAM-1 at 72 h after PCI. Conclusion: There was a negative correlation of miR-126 with the P 展开更多
关键词 High-sensitivity C-reactive Protein MicroRNA126 Percutaneous Coronary Intervention Vascular Cell Adhesion molecule- 1
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B7-H1 expression is associated with expansion of regulatory T cells in colorectal carcinoma 被引量:25
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作者 Dong Hua Jing Sun +3 位作者 Yong Mao Lu-Jun Chen Yu-Yu Wu Xue-Guang Zhang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第9期971-978,共8页
AIM: To investigate the expression of B7-H1 in human colorectal carcinoma (CRC) to define its regulating ef- fects on T cells in tumor microenvironment.
关键词 Costimulatory molecule B7-H1 PD-1 Regu-latory T cell Colorectal carcinoma
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Label-free detection of single nanoparticles and biological molecules using microtoroid optical resonators 被引量:25
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作者 Judith Su Alexander FG Goldberg Brian M Stoltz 《Light(Science & Applications)》 SCIE EI CAS CSCD 2016年第1期863-868,共6页
Single-molecule detection is one of the fundamental challenges of modern biology.Such experiments often use labels that can be expensive,difficult to produce,and for small analytes,might perturb the molecular events b... Single-molecule detection is one of the fundamental challenges of modern biology.Such experiments often use labels that can be expensive,difficult to produce,and for small analytes,might perturb the molecular events being studied.Analyte size plays an important role in determining detectability.Here we use laser-frequency locking in the context of sensing to improve the signal-to-noise ratio of microtoroid optical resonators to the extent that single nanoparticles 2.5 nm in radius,and 15.5 kDa molecules are detected in aqueous solution,thereby bringing these detectors to the size limits needed for detecting the key macromolecules of the cell.Our results,covering several orders of magnitude of particle radius(100 nm to 2 nm),agree with the‘reactive’model prediction for the frequency shift of the resonator upon particle binding.This confirms that the main contribution of the frequency shift for the resonator upon particle binding is an increase in the effective path length due to part of the evanescent field coupling into the adsorbed particle.We anticipate that our results will enable many applications,including more sensitive medical diagnostics and fundamental studies of single receptor–ligand and protein–protein interactions in real time. 展开更多
关键词 BIOSENSING frequency locking LABEL-FREE microtoroid single molecule
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Biomonitoring for traditional herbal medicinal products using DNA metabarcoding and single molecule, real-time sequencing 被引量:23
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作者 Tianyi Xin Zhichao Xu +6 位作者 Jing Jia Christine Leon Songnian Hu Yulin Lin Subramanyam Ragupathy Jingyuan Song Steven G.Newmaster 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2018年第3期488-497,共10页
Global concerns have been paid to the potential hazard of traditional herbal medicinal products(THMPs). Substandard and counterfeit THMPs, including traditional Chinese patent medicine, health foods, dietary supplemen... Global concerns have been paid to the potential hazard of traditional herbal medicinal products(THMPs). Substandard and counterfeit THMPs, including traditional Chinese patent medicine, health foods, dietary supplements, etc. are potential threats to public health. Recent marketplace studies using DNA barcoding have determined that the current quality control methods are not sufficient for ensuring the presence of authentic herbal ingredients and detection of contaminants/adulterants. An efficient biomonitoring method for THMPs is of great needed. Herein, metabarcoding and single-molecule, realtime(SMRT) sequencing were used to detect the multiple ingredients in Jiuwei Qianghuo Wan(JWQHW), a classical herbal prescription widely used in China for the last 800 years. Reference experimental mixtures and commercial JWQHW products from the marketplace were used to confirm the method. Successful SMRT sequencing results recovered 5416 and 4342 circular-consensus sequencing(CCS) reads belonging to the ITS2 and psb A-trn H regions. The results suggest that with the combination of metabarcoding and SMRT sequencing, it is repeatable, reliable, and sensitive enough to detect species in the THMPs, and the error in SMRT sequencing did not affect the ability to identify multiple prescribed species and several adulterants/contaminants. It has the potential for becoming a valuable tool for the biomonitoring of multi-ingredient THMPs. 展开更多
关键词 Traditional herbal medic inal products(THMP) Species mixture Authentication DNA metabarcoding Single molecule real-time(SMRT) sequencing Circular-consensus sequencing(CCS)
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水稻分蘖发生机理的研究进展 被引量:24
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作者 刘杨 王强盛 +1 位作者 丁艳锋 王绍华 《中国农学通报》 CSCD 北大核心 2011年第3期1-5,共5页
分蘖是影响水稻穗数并进而影响其单产的重要农艺性状,是单子叶植物在生长发育过程中形成的一种特殊的分枝特性。水稻分蘖的发生是一个非常复杂的过程,自然条件、植株营养、植物激素、遗传等因素都会影响其发生。深入研究水稻分蘖发生机... 分蘖是影响水稻穗数并进而影响其单产的重要农艺性状,是单子叶植物在生长发育过程中形成的一种特殊的分枝特性。水稻分蘖的发生是一个非常复杂的过程,自然条件、植株营养、植物激素、遗传等因素都会影响其发生。深入研究水稻分蘖发生机理,更加有效的调控分蘖发生,将会进一步提高水稻产量,对水稻生产具有重要意义。前人对水稻分蘖的发生及调控进行了大量研究,作者从形态、环境、激素、分子等4个方面对水稻分蘖发生的机理进行综述。 展开更多
关键词 水稻 分蘖 营养 激素 分子
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Visible light-driven organic photochemical synthesis in China 被引量:22
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作者 Yiyun Chen Liang-Qiu Lu +2 位作者 Da-Gang Yu Cheng-Jian Zhu Wen-Jing Xiao 《Science China Chemistry》 SCIE EI CAS CSCD 2019年第1期24-57,共34页
In recent years, visible light-driven organic photochemical synthesis has attracted wide research interest from academic and industrial communities due to its features of green and sustainable chemistry. In this flour... In recent years, visible light-driven organic photochemical synthesis has attracted wide research interest from academic and industrial communities due to its features of green and sustainable chemistry. In this flourishing area, Chinese chemists have devoted great efforts to different aspects of synthetic chemistry. This review will summarize their representative work according to the following categories: C–H functionalization, synthesis of aromatic aza-heterocycles, asymmetric organic photochemical synthesis, transformations of small molecules and biomolecule-compatible reactions. 展开更多
关键词 visible light PHOTOCHEMICAL synthesis C–H FUNCTIONALIZATION aromatic aza-heterocycle asymmetric catalysis biomolecule-compatible reaction small molecule
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The effects of probiotics administration on the milk production,milk components and fecal bacteria microbiota of dairy cows 被引量:23
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作者 Haiyan Xu Weiqiang Huang +6 位作者 Qiangchuan Hou Lai-yu Kwok Zhihong Sun Huimin Ma Feiyan Zhao Yuan-Kun Lee Heping Zhang 《Science Bulletin》 SCIE EI CAS CSCD 2017年第11期767-774,共8页
Probiotics administration can improve host health. This study aims to determine the effects of probiotics (Lactobacillus casei Zhang and Lactobacillus plantarum P-8) administration on milk production, milk func- tio... Probiotics administration can improve host health. This study aims to determine the effects of probiotics (Lactobacillus casei Zhang and Lactobacillus plantarum P-8) administration on milk production, milk func- tional components, milk composition, and fecal microbiota of dairy cows. Variations in the fecal bacteria microbiota between treatments were assessed based on 16S rRNA profiles determined by PacBio single molecule real-time sequencing technology. The probiotics supplementation significantly increased the milk production and the contents of milk immunoglobulin C (IgG), lactoferrin (LTF), lysozyme (LYS) and lactoperoxidase (LP), while the somatic cell counts (SCC) significantly decreased (P〈0.01). However, no significant difference was found in the milk fat, protein and lactose contents (P 〉 0.05). Although the probiotics supplementation did not change the fecal bacteria richness and diversity, significantly more rumen fermentative bacteria ( Bacteroides, Roseburia, Ruminococcus, CIostridium, Coprococcus and Dorea) and beneficial bacteria (Faecalibacterium prausnitzii) were found in the probiotics treatment group. Meanwhile, some opportunistic pathogens e.g. Bacillus cereus, Cronobacter sakazakii and Alkaliphilus oremlandii, were suppressed. Additionally, we found some correlations between the milk production, milk components and fecal bacteria. To sum up, our study demonstrated the beneficial effects of probiotics application in improving the quality and quantity of cow milk production. 展开更多
关键词 Milk production Milk components Fecal bacteria Prnbintics Dairy cow PacBio single molecule real-time sequencing technology
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产超广谱β内酰胺酶49株细菌耐药基因调查 被引量:22
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作者 孙自镛 程黎明 +3 位作者 朱旭慧 李丽 张蓓 俞云松 《中华检验医学杂志》 CAS CSCD 北大核心 2006年第9期793-796,共4页
目的了解49株产超广谱 B 内酰胺酶(ESBLs)细菌的耐药基因。方法采用纸片扩散法检测产 ESBLs 细菌,通过基因扩增、序列分析、脉冲场凝胶电泳技术研究 ESBLs 基因型以及产ESBLs 细菌同源性。结果产 ESBLs 大肠埃希菌、肺炎克雷伯菌、产酸... 目的了解49株产超广谱 B 内酰胺酶(ESBLs)细菌的耐药基因。方法采用纸片扩散法检测产 ESBLs 细菌,通过基因扩增、序列分析、脉冲场凝胶电泳技术研究 ESBLs 基因型以及产ESBLs 细菌同源性。结果产 ESBLs 大肠埃希菌、肺炎克雷伯菌、产酸克雷伯菌流行率自2000年的20%,增长至2003年的40%。49株产 ESBLs 细菌中,以 CTX-M-14(n=33)亚型最常见,其他亚型包括 CTX-M-3、CTX-M-9、CTX-M-12、CTX-M-15、CTX-M-24、SHV-5a,1株细菌同时产 CTX-M-3、CTX-M-14两种 CTX-M 型 ESBLs;4株表型确证试验阳性细菌未能分型。除2株大肠埃希菌、2株肺炎克雷伯菌有亲缘性外,其他菌株间无同源性。结论产 ESBLs 细菌分离率逐年增高,以 CTX-M 型酶为主。PFGE 试验证明非流行所致。 展开更多
关键词 Β内酰胺酶类 基因型 流行病学 分子
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黄芪多糖对免疫作用的研究进展 被引量:22
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作者 李飞飞 沈建平 庄海峰 《医学综述》 2012年第8期1227-1229,共3页
黄芪为豆科多年生草本植物,药用部位为根,是一种常用的扶正中药。黄芪中的化学成分富含多糖、皂苷、氨基酸等。多糖是一类生物高分子,随着分子生物学的发展,糖类及其结合物分子具有极其重要的生物功能已逐渐被人们所认识,黄芪多糖(APS)... 黄芪为豆科多年生草本植物,药用部位为根,是一种常用的扶正中药。黄芪中的化学成分富含多糖、皂苷、氨基酸等。多糖是一类生物高分子,随着分子生物学的发展,糖类及其结合物分子具有极其重要的生物功能已逐渐被人们所认识,黄芪多糖(APS)具有免疫促进功能的研究时有报道。现就APS对免疫器官、免疫细胞及免疫分子的作用予以综述。 展开更多
关键词 黄芪多糖 免疫调节 器官 细胞 分子
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植物耐盐的分子生物学基础 被引量:14
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作者 马建华 郑海雷 《生物学杂志》 CAS CSCD 2007年第1期5-8,4,共5页
植物分子水平的耐盐研究是近年的研究热点,通过综述与耐盐有关的几种重要分子的性质和作用,总结了几种与植物耐盐有关的基因以及它们在盐分胁迫下的表达和调控。
关键词 耐盐性 分子 渗调蛋白 基因表达
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耐甲氧西林凝固酶阴性葡萄球菌产酶耐药基因分子流行病学研究 被引量:21
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作者 巴特尔 郭淑英 张亚荣 《中华医院感染学杂志》 CAS CSCD 北大核心 2005年第6期605-607,共3页
目的了解耐甲氧西林凝固酶阴性葡萄球菌(MRCNS)产酶耐药基因流行病学状况。方法我们对55 株MRCNS菌进行了TEM 1基因(编码青霉素酶)、aph(3') Ⅲ和aac(6')/aph(2")基因(编码氨基糖苷类修饰酶)、erm基因(编码红霉素甲基化酶... 目的了解耐甲氧西林凝固酶阴性葡萄球菌(MRCNS)产酶耐药基因流行病学状况。方法我们对55 株MRCNS菌进行了TEM 1基因(编码青霉素酶)、aph(3') Ⅲ和aac(6')/aph(2")基因(编码氨基糖苷类修饰酶)、erm基因(编码红霉素甲基化酶)检测。结果55 株MRCNS菌TEM 1、aph(3') Ⅲ和aac(6')/aph(2")、erm基因阳性株分别为54、43、16、45 株,阳性率分别为98 .2%、78 .2%、29 .1%、81. 8%;其中同时检出TEM -1 基因、aph(3') Ⅲ或aac(6')/aph(2")基因、erm基因39 株(70 .9%)。结论70 .9% MRCNS菌已同时携带青霉素酶、氨基糖苷类修饰酶和红霉素甲基化酶基因。 展开更多
关键词 葡萄球菌属 流行病学 分子 基因
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白内障发病机制的分子学研究进展 被引量:12
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作者 唐建 《眼科新进展》 CAS 2003年第1期52-55,共4页
通过白内障在分子学方面的研究进展 ,包括生物大分子、氧自由基、细胞骨架、膜复合体、离子与酶等在白内障发病机制中的转变与联系 。
关键词 白内障 发病机制 分子学 生物大分子 氧自由基 细胞骨架 膜复合体 离子
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