期刊文献+
共找到22篇文章
< 1 2 >
每页显示 20 50 100
Prognositic value of anoikis and tumor immune microenvironment-related gene in the treatment of osteosarcoma 被引量:1
1
作者 WANG Dong DENG Qing +7 位作者 PENG Yi TONG Zhaochen LI Zixin HUANG Liping ZENG Jin LI Jinsong MIAO Jinglei CHEN Shijie 《中南大学学报(医学版)》 CAS CSCD 北大核心 2024年第5期758-774,共17页
Objective:Osteosarcoma is a highly aggressive primary malignant bone tumor commonly seen in children and adolescents,with a poor prognosis.Anchorage-dependent cell death(anoikis)has been proven to be indispensable in ... Objective:Osteosarcoma is a highly aggressive primary malignant bone tumor commonly seen in children and adolescents,with a poor prognosis.Anchorage-dependent cell death(anoikis)has been proven to be indispensable in tumor metastasis,regulating the migration and adhesion of tumor cells at the primary site.However,as a type of programmed cell death,anoikis is rarely studied in osteosarcoma,especially in the tumor immune microenvironment.This study aims to clarify prognostic value of anoikis and tumor immune microenvironment-related gene in the treatment of osteosarcoma.Methods:Anoikis-related genes(ANRGs)were obtained from GeneCards.Clinical information and ANRGs expression profiles of osteosarcoma patients were sourced from the therapeutically applicable research to generate effective therapies and Gene Expression Omnibus(GEO)databases.ANRGs highly associated with tumor immune microenvironment were identified by the estimate package and the weighted gene coexpression network analysis(WGCNA)algorithm.Machine learning algorithms were performed to construct long-term survival predictive strategy,each sample was divided into high-risk and low-risk subgroups,which was further verified in the GEO cohort.Finally,based on single-cell RNA-seq from the GEO database,analysis was done on the function of signature genes in the osteosarcoma tumor microenvironment.Results:A total of 51 hub ANRGs closely associated with the tumor microenvironment were identified,from which 3 genes(MERTK,BNIP3,S100A8)were selected to construct the prognostic model.Significant differences in immune cell activation and immune-related signaling pathways were observed between the high-risk and low-risk groups based on tumor microenvironment analysis(all P<0.05).Additionally,characteristic genes within the osteosarcoma microenvironment were identified in regulation of intercellular crosstalk through the GAS6-MERTK signaling pathway.Conclusion:The prognostic model based on ANRGs and tumor microenvironment demonstrate good predictive power and provide more personalized treatment options for patients with osteosarcoma. 展开更多
关键词 ANOIKIS tumor immune microenvironment BIOINFORMATICS PROGNOSIS OSTEOSARCOMA
在线阅读 下载PDF
Modulation Effects of the 3D Strain Microenvironment on Characteristics of Mesenchymal Stem Cell-Derived Exosomes
2
作者 Yufei Ma Wenting Yu Feng Xu 《医用生物力学》 EI CAS CSCD 北大核心 2019年第A01期128-129,共2页
It is necessary to investigate the characteristics of Mesenchymal stem cells(MSCs)derived exosomes,and especially their application in tissue regeneration.Previous studies have shown that inflammatory stimulation enha... It is necessary to investigate the characteristics of Mesenchymal stem cells(MSCs)derived exosomes,and especially their application in tissue regeneration.Previous studies have shown that inflammatory stimulation enhanced the secretion of MSC-derived exosomes with stronger anti-inflammatory protein,cytokine profiles,and functional RNA via altering COX2/PGE2 pathway.Recently,accumulating evidence has also revealed that biophysical cues(especially biomechanical cues)in cell microenvironment have significant effects not only on cells but also on their exosomes.It has been reported that applying bi-axial strain to MSCs induces formation of a stiffer cytoskeleton through mTORC2 signaling,which biases against adipogenic differentiation and toward osteoblastogenesis.At the same time,For example,dimensionality,composition and stiffness of the extracellular matrix(ECM)has been proved to affect the size and composition of exosomes secreted by cancer cells.However,the effects of biomechanical cues in the three-dimensional(3D)microenvironment on stem cell-derived exosomes remains to be unveiled.Therefore,it is important to understand the roles of 3D cell mechanical microenvironment in regulating the characteristics of stem cell-derived exosomes and develop more efficient approaches to enhance their functions.This study aimed to explore the changes in characteristics of exosomes secreted by MSCs in periodontium in response to the matrix strain in 3D.Periodontal ligament stem cells(PDLSCs)were cultured in a 3D strain microenvironment engineered with microscale magnetically stretched collagen hydrogels.The morphology,particle distribution,marker protein expression of PDLSC-derived exosomes were analyzed.Then the pro-osteogenic property of exosomes was evaluated by assessing cell viability,proliferation,migration and osteogenic differentiation of target cells,for instance human bone marrow mesenchymal stem cells(hBMSCs).Detailed characterizations revealed that PDLSC-derived exosomes in the 3D strain mi-croenvironment were with similar morphology,particle distribution and surface markers.Notably,Exosomes secreted by PDLSCs in strain microenvironment were more endocytosed by hBMSCs and were more potent in improving proliferation and migration of hBMSCs,comparing with PDLSCs in non-strain environment.Alizarin red staining and molecular biology experiments confirmed that treatment of exosomes secreted by PDLSCs under mechanical stimulation led to a significant increase in osteogenic differentiation of hBMSCs in vitro.Meanwhile,in vivo study also indicated that PDLSC-derived exosomes obtained from the 3D strain microenvironment could obviously promote new bone formation.Our findings revealed that mechanical cues profoundly affected the characteristics of PDLSC-derived exosomes,especially for their bio-activity,providing a foundation for using the 3D mechanical microenvironment to enhance the osteo-inductive functions of stem cell-derived exosomes in cell-free therapy for bone regeneration. 展开更多
关键词 Modulation Effects the 3D STRAIN microenvironment CHARACTERISTICS Mesenchymal Stem Cell-Derived EXOSOMES
在线阅读 下载PDF
Engineering of Cell Spatiotemporal Mechanical Microenvironment
3
作者 Feng Xu 《医用生物力学》 EI CAS CSCD 北大核心 2019年第A01期34-34,共1页
Cells in vivo are in a three-dimensional(3D)complicated microenvironment composed of various biological,physical and chemical cues.Although it is well accepted that biological and chemical cues can significantly influ... Cells in vivo are in a three-dimensional(3D)complicated microenvironment composed of various biological,physical and chemical cues.Although it is well accepted that biological and chemical cues can significantly influence cell functions,more and more evidence has also shown that physical cues are also vital.Using today’s micro and nanoscale technologies,creating synthetic but native-like conditions are the prerequisites for understanding cell behaviors.Most research has been carried out on artificial two-dimensional(2D)substrates.However,recent studies showed that cells respond and behave differently in these 2D settings compared to in 3D intricate microenvironment.Therefore,innovative 3D in vitro cellular models with precisely patterned multiple types of cells are needed for re-creating distinct niches and in vitro cell modeling under well-defined and reproducible conditions.In this talk,I will present the 3D nano and microscale tissue engineering methods we are developing for engineering cell spatiotemporal mechanical microenvironment. 展开更多
关键词 ENGINEERING CELL SPATIOTEMPORAL MECHANICAL microenvironment
在线阅读 下载PDF
Construction of microenvironmental biointerfaces
4
作者 Kaiyong Cai,Yan Hu,Zhong Luo(Key Laboratory of Biorheological Science and Technology,Ministry of Education,College of Bioengineering,Chongqing University,Chongqing 400044,China) 《医用生物力学》 EI CAS CSCD 2010年第S1期52-53,共2页
Biomaterial acts as artificial extracellular matrix for providing a provisional three-dimensional (3D) microenvironments to interact biophysically and/or biochemically with cells to regulate cell behaviors,such as cel... Biomaterial acts as artificial extracellular matrix for providing a provisional three-dimensional (3D) microenvironments to interact biophysically and/or biochemically with cells to regulate cell behaviors,such as cell adhesion,migration,prolifera- 展开更多
关键词 CELL GENE Construction of microenvironmental biointerfaces
在线阅读 下载PDF
Microenvironmental biomaterials
5
作者 Kaiyong Cai Yan Hu Zhong Luo 《医用生物力学》 EI CAS CSCD 2009年第S1期49-49,共1页
Biomaterials play essential role in regenerative medicine and tissue engineering,which providing a provisional three-dimensional(3D)microenvironments to interact biophysically and/or biochemically with cells to guide ... Biomaterials play essential role in regenerative medicine and tissue engineering,which providing a provisional three-dimensional(3D)microenvironments to interact biophysically and/or biochemically with cells to guide cellular performance[1].It thus spatially and temporally regulates complex cellular process of tissue formation,function and regeneration. 展开更多
关键词 GENE microenvironmental biomaterials
在线阅读 下载PDF
PD-1、VISTA表达与子宫内膜癌微环境中Th1/Th2、Th17/Treg、Th22失衡的相关性研究
6
作者 柴静 张家弘 李梦雪 《实用妇产科杂志》 北大核心 2025年第7期574-579,共6页
目的:研究组织程序性死亡受体-1(PD-1)、含V结构域抑制T细胞活化的免疫球蛋白(VISTA)表达与子宫内膜癌(EC)微环境中辅助性T淋巴细胞(Th)1/Th2、Th17/调节性T细胞(Treg)、Th22失衡的相关性。方法:选择2020年3月1日至2023年6月30日于唐山... 目的:研究组织程序性死亡受体-1(PD-1)、含V结构域抑制T细胞活化的免疫球蛋白(VISTA)表达与子宫内膜癌(EC)微环境中辅助性T淋巴细胞(Th)1/Th2、Th17/调节性T细胞(Treg)、Th22失衡的相关性。方法:选择2020年3月1日至2023年6月30日于唐山市妇幼保健院收治的94例EC患者(EC组)、94例子宫内膜不典型增生患者(AH组)及94例无EC、AH等子宫和子宫内膜相关疾病人群(对照组),比较各组组织中PD-1、VISTA的表达及子宫内膜微环境中Th1/Th2、Th17/Treg、Th22水平,应用Pearson分析组织PD-1、VISTA表达与EC微环境中Th1/Th2、Th17/Treg、Th22失衡的相关性,并比较不同病理特征患者组织PD-1、VISTA阳性表达情况。结果:(1)EC组、AH组中PD-1、VISTA的表达高于对照组,且EC组高于AH组,差异均有统计学意义(P<0.05);EC组、AH组子宫内膜微环境中的Th1/Th2、Th17/Treg表达低于对照组,Th22的表达高于对照组,且EC组Th1/Th2、Th17/Treg表达低于AH组,Th22表达高于AH组,以上差异均有统计学意义(P<0.05)。(2)对照组PD-1、VISTA的表达与微环境中Th1/Th2、Th17/Treg、Th22均无相关性(P>0.05);AH组和EC组中PD-1、VISTA的表达均与微环境中Th1/Th2、Th17/Treg呈负相关(r<0,P<0.05),与Th22呈正相关(r>0,P<0.05)。(3)EC患者中,PD-1的表达与其临床分期、浸润深度、淋巴结转移有关(P<0.05);VISTA的表达与其临床分期、淋巴结转移有关(P<0.05)。结论:EC组织中PD-1、VISTA呈高表达,与肿瘤微环境中Th1/Th2、Th17/Treg、Th22失衡及EC侵袭性密切相关,PD-1、VISTA免疫检查点双抑制策略或能为EC治疗提供一个新思路。 展开更多
关键词 程序性死亡受体-1 含V结构域抑制T细胞活化的免疫球蛋白 子宫内膜癌 辅助性T淋巴细胞 调节性T细胞 微环境免疫失衡 相关性
在线阅读 下载PDF
牯牛降常绿阔叶林群落结构、谱系结构及其影响因子
7
作者 朱林 张昊楠 +3 位作者 洪欣 陈达伟 秦卫华 周守标 《生态与农村环境学报》 北大核心 2025年第3期358-366,共9页
植物群落的群落结构、谱系结构既取决于非生物环境因子的空间异质性,又受群落内生物间相互作用的影响,但不同影响因子之间的相对重要性仍需进一步探讨。本研究以西黄山山脉牯牛降南北坡常绿阔叶林群落为对象,使用全站仪建立2个1 hm^(2)... 植物群落的群落结构、谱系结构既取决于非生物环境因子的空间异质性,又受群落内生物间相互作用的影响,但不同影响因子之间的相对重要性仍需进一步探讨。本研究以西黄山山脉牯牛降南北坡常绿阔叶林群落为对象,使用全站仪建立2个1 hm^(2)固定样地,对所有乔木个体(胸径≥1cm)进行空间定位并确定海拔、坡度等微生境变量,并结合单木竞争模型获取邻域竞争指数变量。通过拟合广义线性混合效应模型和一般线性模型,将两组变量(微生境效应、邻域竞争效应)中的多个因子作为解释变量,分析在局域尺度上南北坡森林群落结构和谱系结构差异。结果显示:(1)在该区域内,南北坡的环境差异对植物群落结构和谱系结构有一定影响,北坡群落的物种多样性更丰富且亲缘度更近。(2)植物群落结构和谱系结构受生境过滤和邻域竞争的共同影响,两者共同驱动群落物种β多样性的形成。(3)环境因子和邻域竞争因子对群落结构、谱系结构的影响随着生活史阶段的变化而变化。树木在生长初期主要受邻域效应的影响,在生长后期主要受微生境因子的影响,这表明它们的资源获取策略以及对邻域竞争效应和环境因素的响应也在发生变化。本研究结果可为本区域生物多样性的维持机制研究提供科学参考。 展开更多
关键词 谱系结构 微生境因子 邻域效应 广义线性混合效应模型
在线阅读 下载PDF
二维无机材料调控病损皮肤组织再生的研究进展
8
作者 肖晓琳 王玉祥 +2 位作者 谷佩洋 朱圳荣 孙勇 《无机材料学报》 北大核心 2025年第8期860-870,共11页
二维无机材料作为一类具有单原子层或多原子层的无机超薄纳米片,呈现出高比表面积、高导电性和/或高光热转换效率等特点。这些独特的理化特性赋予其促凝血、抗菌、抗炎和抗氧化等生物效应。近年来,鉴于降解和代谢问题,该类材料被应用于... 二维无机材料作为一类具有单原子层或多原子层的无机超薄纳米片,呈现出高比表面积、高导电性和/或高光热转换效率等特点。这些独特的理化特性赋予其促凝血、抗菌、抗炎和抗氧化等生物效应。近年来,鉴于降解和代谢问题,该类材料被应用于调控病损皮肤组织,如全层皮肤缺损、烧烫伤及糖尿病创面等,展现出加速伤口愈合、减轻感染及改善炎症微环境的显著效果。本文围绕二维无机材料的特有结构和生物效应,系统性阐述了其在伤口愈合中的应用及相关作用机制,并展望了二维无机材料在皮肤修复领域面临的挑战和前景。 展开更多
关键词 二维无机材料 皮肤修复 微环境调节 综述
在线阅读 下载PDF
利用实时监测和运动轨迹分析方法评估西南地区农村居民PM_(2.5)暴露
9
作者 钟国梁 符楠 +5 位作者 王平书 杨明 王金泽 沈国锋 林楠 杜伟 《生态毒理学报》 北大核心 2025年第4期204-213,共10页
PM_(2.5)暴露对全球人类健康构成严重威胁,且这一问题正日益受到关注。然而,PM_(2.5)暴露评估方法的准确性尚未得到充分验证,这为居民健康风险评估带来了不确定性。本研究利用实时PM_(2.5)监测仪和详细的活动轨迹调查,量化了云南省玉溪... PM_(2.5)暴露对全球人类健康构成严重威胁,且这一问题正日益受到关注。然而,PM_(2.5)暴露评估方法的准确性尚未得到充分验证,这为居民健康风险评估带来了不确定性。本研究利用实时PM_(2.5)监测仪和详细的活动轨迹调查,量化了云南省玉溪市农村地区47户家庭居民的真实PM_(2.5)暴露情况。研究还通过对比分析时间加权法和时间分配法的评估准确性,探讨了各微环境对居民PM_(2.5)暴露的浓度贡献、暴露时间占比和暴露强度。结果表明,由于无法实时捕捉环境污染的动态变化,时间加权法显著低估了居民PM_(2.5)暴露水平,而时间分配法结合了居民24 h的活动轨迹和实时PM_(2.5)浓度数据,通过考虑居民在各个微环境中的停留时间和对应的实时浓度提供更准确的健康风险评估依据。厨房/室外(K/O)、客厅/室外(L/O)和卧室/室外(B/O)的PM_(2.5)浓度比值分别为1.4±0.4、1.3±0.5和1.2±0.6,均大于1,表明农村居民家庭的PM_(2.5)污染主要由室内源贡献。烹饪活动导致午餐和晚餐时间的个人暴露达到峰值,显著增加了全天的个人PM_(2.5)暴露。卧室是居民PM_(2.5)暴露的主要来源,贡献率达38.0%,同时也是暴露时间最长的微环境,占比40.3%。虽然个体居民在厨房的暴露时间较短,但暴露强度最大(1.4±1.1),提示短期的高强度PM_(2.5)暴露对健康风险的潜在影响不容忽视。厨房暴露贡献和暴露强度呈现显著的性别差异,女性在厨房暴露时间更长,尤其是老年女性,这表明烹饪活动是导致PM_(2.5)暴露水平升高的重要因素。本研究为评估居民PM_(2.5)暴露提供了新的视角,并为制定减少居民PM_(2.5)暴露的干预策略提供科学依据。 展开更多
关键词 室内空气污染 农村居民PM_(2.5)暴露 实时监测 时间分配法 微环境暴露贡献
在线阅读 下载PDF
A Prognostic Model Based on Colony Stimulating Factors-related Genes in Triple-negative Breast Cancer
10
作者 GUO Yu-Xuan WANG Zhi-Yu +7 位作者 XIAO Pei-Yao ZHENG Chan-Juan FU Shu-Jun HE Guang-Chun LONG Jun WANG Jie DENG Xi-Yun WANG Yi-An 《生物化学与生物物理进展》 SCIE CAS CSCD 北大核心 2024年第10期2741-2756,共16页
Objective Triple-negative breast cancer(TNBC)is the breast cancer subtype with the worst prognosis,and lacks effective therapeutic targets.Colony stimulating factors(CSFs)are cytokines that can regulate the production... Objective Triple-negative breast cancer(TNBC)is the breast cancer subtype with the worst prognosis,and lacks effective therapeutic targets.Colony stimulating factors(CSFs)are cytokines that can regulate the production of blood cells and stimulate the growth and development of immune cells,playing an important role in the malignant progression of TNBC.This article aims to construct a novel prognostic model based on the expression of colony stimulating factors-related genes(CRGs),and analyze the sensitivity of TNBC patients to immunotherapy and drug therapy.Methods We downloaded CRGs from public databases and screened for differentially expressed CRGs between normal and TNBC tissues in the TCGA-BRCA database.Through LASSO Cox regression analysis,we constructed a prognostic model and stratified TNBC patients into high-risk and low-risk groups based on the colony stimulating factors-related genes risk score(CRRS).We further analyzed the correlation between CRRS and patient prognosis,clinical features,tumor microenvironment(TME)in both high-risk and low-risk groups,and evaluated the relationship between CRRS and sensitivity to immunotherapy and drug therapy.Results We identified 842 differentially expressed CRGs in breast cancer tissues of TNBC patients and selected 13 CRGs for constructing the prognostic model.Kaplan-Meier survival curves,time-dependent receiver operating characteristic curves,and other analyses confirmed that TNBC patients with high CRRS had shorter overall survival,and the predictive ability of CRRS prognostic model was further validated using the GEO dataset.Nomogram combining clinical features confirmed that CRRS was an independent factor for the prognosis of TNBC patients.Moreover,patients in the high-risk group had lower levels of immune infiltration in the TME and were sensitive to chemotherapeutic drugs such as 5-fluorouracil,ipatasertib,and paclitaxel.Conclusion We have developed a CRRS-based prognostic model composed of 13 differentially expressed CRGs,which may serve as a useful tool for predicting the prognosis of TNBC patients and guiding clinical treatment.Moreover,the key genes within this model may represent potential molecular targets for future therapies of TNBC. 展开更多
关键词 triple-negative breast cancer colony stimulating factors prognostic model tumor microenvironment drug sensitivity
在线阅读 下载PDF
植物光自养微繁殖技术的发展及应用 被引量:1
11
作者 韩孟鑫 张梦阳 +3 位作者 荣俊博 李艳露 王英平 雷秀娟 《特产研究》 2024年第3期168-173,共6页
植物光自养微繁殖技术以CO_(2)作为碳源,通过对影响试管苗生长发育的环境因子来调控优质种苗的快速生产,是组织培养的创新发展技术,可克服传统组培苗生根质量差、移栽成活率低等问题。本文系统综述了国内外光自养微繁殖技术的产生和发展... 植物光自养微繁殖技术以CO_(2)作为碳源,通过对影响试管苗生长发育的环境因子来调控优质种苗的快速生产,是组织培养的创新发展技术,可克服传统组培苗生根质量差、移栽成活率低等问题。本文系统综述了国内外光自养微繁殖技术的产生和发展,重点介绍微环境因子的调控以及监控系统的开发应用,并对该技术的未来发展提出展望,以期为我国药用植物种苗产业的发展和植物分子育种提供理论和方法基础。 展开更多
关键词 光自养微繁殖 微环境调控 监控系统应用
在线阅读 下载PDF
计算解析异常代谢对乳腺癌微环境重塑的调控机制 被引量:3
12
作者 万羽鑫 朱欣雨 +3 位作者 赵宇 孙娜 江天彤妃 徐娟 《遗传》 CAS CSCD 北大核心 2024年第10期871-885,共15页
肿瘤微环境(tumor microenvironment,TME)中T细胞亚群的组成和肿瘤特异的T细胞互作促进了乳腺癌异质性的形成。此外,肿瘤的异常代谢通常与T细胞的抗肿瘤免疫功能失调关联密切,识别影响免疫细胞互作的关键代谢基因能够为乳腺癌治疗提供... 肿瘤微环境(tumor microenvironment,TME)中T细胞亚群的组成和肿瘤特异的T细胞互作促进了乳腺癌异质性的形成。此外,肿瘤的异常代谢通常与T细胞的抗肿瘤免疫功能失调关联密切,识别影响免疫细胞互作的关键代谢基因能够为乳腺癌治疗提供潜在靶点。本研究利用乳腺癌单细胞转录组数据,重点研究了乳腺癌发展过程中肿瘤特异性T细胞亚群及其互作子网,进一步评估肿瘤特异性激活的T细胞亚群的代谢通路活性。结果显示,肠促胰岛素的合成、分泌和失活的代谢通路以及果糖分解代谢通路显著影响了多个T细胞亚群的互作。整合肿瘤中T细胞显著上调以及影响互作的代谢通路,依此筛选出核心T细胞互作相关的异常代谢基因,并进一步构建乳腺癌风险评估模型。利用异常代谢显著相关预后基因表达谱与药物IC50值预测靶向药物,最终获得潜在靶向药物GSK-J4、PX-12等。本研究整合分析乳腺癌微环境中T细胞互作的重塑与代谢通路异常在癌症恶性进展中的作用,为新型乳腺癌抗癌疗法提供线索。 展开更多
关键词 乳腺癌 微环境重塑 异常代谢 T细胞互作
在线阅读 下载PDF
β-胡萝卜素和α-生育酚协同抗氧化作用的微环境效应 被引量:7
13
作者 李兆陇 马兰萍 +1 位作者 刘有成 刘中立 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 1997年第11期1814-1819,共6页
分别用水溶性和脂溶性的偶氮引发剂2,2'-偶氮二(2-眯基丙烷)二盐酸盐(AAPH)和连二次硝酸二叔丁酯(DBHN)引发亚油酸的过氧化,用氧气吸收法研究了β-胡萝卜素(β-C)和α-生育酚(VE)在负离子胶束十二烷基硫酸钠(SDS)、... 分别用水溶性和脂溶性的偶氮引发剂2,2'-偶氮二(2-眯基丙烷)二盐酸盐(AAPH)和连二次硝酸二叔丁酯(DBHN)引发亚油酸的过氧化,用氧气吸收法研究了β-胡萝卜素(β-C)和α-生育酚(VE)在负离子胶束十二烷基硫酸钠(SDS)、非离子胶束辛基苯基聚氧乙烯醚(TritonX-100)和正离子胶束十六烷基三甲基溴化铵(CTAB)中对亚油酸自动氧化的抗氧化和协同抗氧化作用.发现它们的抗氧化活性强烈地依赖于介质的微观环境及引发剂的亲脂性.β-C仅在SDS胶束中对DBHN引发的亚油酸过氧化有明显的抗氧化作用,但在SDS和TritonX-100中β-C可以和VE协同作用,显著加强VE对AAPH和DBHN引发的亚油酸过氧化的抑制作用.讨论了抗氧化活性与介质微环境的关系. 展开更多
关键词 微环境效应 Β-胡萝卜素 维生素E 抗氧化活性
在线阅读 下载PDF
水分胁迫对美国凌霄单叶水分利用效率的影响 被引量:9
14
作者 夏江宝 孙景宽 张光灿 《西北植物学报》 CAS CSCD 北大核心 2009年第1期154-159,共6页
利用CIRAS-2型便携式光合作用仪对水分胁迫下3年生美国凌霄(Campsis radicans L.Seen)单叶水分利用效率(WUEleaf)的日动态及其与微环境因子的关系进行了测定分析,以阐明其WUEleaf对土壤水分及光照强度的响应规律,探讨美国凌霄维持较高WU... 利用CIRAS-2型便携式光合作用仪对水分胁迫下3年生美国凌霄(Campsis radicans L.Seen)单叶水分利用效率(WUEleaf)的日动态及其与微环境因子的关系进行了测定分析,以阐明其WUEleaf对土壤水分及光照强度的响应规律,探讨美国凌霄维持较高WUEleaf所需的土壤水分和光照条件。结果表明:(1)随着水分胁迫的加重,美国凌霄WUEleaf表现为减弱趋势,但适度的水分胁迫有利于WUEleaf的提高。(2)水分胁迫下,美国凌霄WUEleaf多与空气相对湿度、大气CO2浓度呈极显著正相关,与饱和水汽压差、大气温度、叶温呈极显著负相关;微环境因子对美国凌霄WUEleaf的影响较为复杂,其中大气CO2浓度、胞间CO2浓度、叶温对其影响较大。(3)维持美国凌霄较高WUEleaf的适宜土壤含水量为10.7%~23.1%(相对含水量为39.2%~84.6%),适宜光照强度在600~1 600μmol·m-2·s-1之间。 展开更多
关键词 美国凌霄 水分胁迫 水分利用效率 微环境因子
在线阅读 下载PDF
阔叶红松林林隙近地层光照微环境异质性分析 被引量:14
15
作者 段文标 李岩 陈立新 《中国水土保持科学》 CSCD 2007年第6期82-86,共5页
以小兴安岭阔叶红松林林隙为研究对象,采用地统计学方法对林隙近地层光照的微环境异质性进行分析。结果表明:1)各月份林隙近地层平均光照水平呈单峰变化趋势,6月份林隙光照水平最高,而最大值出现在7月份;各月份林隙近地层光照变异程度... 以小兴安岭阔叶红松林林隙为研究对象,采用地统计学方法对林隙近地层光照的微环境异质性进行分析。结果表明:1)各月份林隙近地层平均光照水平呈单峰变化趋势,6月份林隙光照水平最高,而最大值出现在7月份;各月份林隙近地层光照变异程度均属于中等变异,6月份变异程度较大,5月份最小。2)各月份林隙光照空间变异程度不同,并呈单峰型变化趋势;除5月份以外,其他月份林隙光照自相关部分的空间异质性在总空间异质性中占主要部分,并表现出较强变异趋势。3)各月份林隙内光斑出现的位置一致,均位于林隙东侧,但各月份林隙内光斑强弱及分布复杂程度不同。 展开更多
关键词 阔叶红松林 林隙 光照 微环境异质性
在线阅读 下载PDF
阔叶红松林林隙土壤物理性质微环境异质性分析 被引量:11
16
作者 李岩 段文标 陈立新 《中国水土保持科学》 CSCD 2007年第3期52-58,共7页
以小兴安岭阔叶红松林林隙为研究对象,采用地统计学方法对林隙0-20 cm和20-40 cm土层土壤物理性质的微环境异质性进行分析。结果表明:阔叶红松林林隙表层土壤含水量、饱和持水量、毛管持水量和孔隙度均大于下层,但土壤密度相反;表层土... 以小兴安岭阔叶红松林林隙为研究对象,采用地统计学方法对林隙0-20 cm和20-40 cm土层土壤物理性质的微环境异质性进行分析。结果表明:阔叶红松林林隙表层土壤含水量、饱和持水量、毛管持水量和孔隙度均大于下层,但土壤密度相反;表层土壤物理性质有相对高的极差和变异系数。土壤物理性质总空间异质性程度和由空间自相关引起的异质性均为表层土壤高于下层。土壤含水量表现出明显各向异性,土壤孔隙度趋近于各向同性,其他3个物理因子随空间距离增大而表现出各向异性。表层土壤物理性质在空间自相关范围内变异函数相互影响较小。不同层次土壤物理性质空间分布均以中低等级斑块为主,相对较高等级的斑块仅分布在0-20 cm土层中,并位于林隙中心以北的范围内。 展开更多
关键词 阔叶红松林 林隙 土壤物理性质 微环境异质性
在线阅读 下载PDF
微环境气调对冰温贮藏下蓝莓果实品质及挥发性成分的影响 被引量:9
17
作者 薛友林 于弘弢 +2 位作者 张鹏 贾晓昱 李江阔 《食品工业科技》 CAS 北大核心 2021年第18期334-341,共8页
为了明确不同气体微环境对冰温贮藏蓝莓品质和挥发性成分的影响,以‘莱克西’蓝莓为试材,研究不同的气体微环境在冰温贮藏(-0.5±0.3℃)0~80 d期间果实品质和挥发性成分的变化。结果表明,在贮藏期间,3种不同的气调环节中,O_(2)变化... 为了明确不同气体微环境对冰温贮藏蓝莓品质和挥发性成分的影响,以‘莱克西’蓝莓为试材,研究不同的气体微环境在冰温贮藏(-0.5±0.3℃)0~80 d期间果实品质和挥发性成分的变化。结果表明,在贮藏期间,3种不同的气调环节中,O_(2)变化范围分别为15.4%~18.2%、13.1%~15.9%和6.1%~13.4%,CO_(2)变化范围分别为2.2%~4.5%、4.5%~8.8%和8.8%~14.8%。与对照相比,微环境气体调控延缓了蓝莓果实的营养物质(VC、花色苷和可滴定酸)和硬度的下降,保持了较低的腐烂率和较高的果霜覆盖指数,还能够抑制醛类物质生成,促进萜类物质的生成。其中,O_(2)含量维持在6.1%~13.4%,CO_(2)含量维持在8.8%~14.8%的气体微环境对蓝莓贮藏的效果最佳,有利于蓝莓果实的长期贮藏。 展开更多
关键词 蓝莓 微环境气调 果实品质 挥发性成分
在线阅读 下载PDF
白桦不同方向功能叶片对微环境因子的光合响应 被引量:6
18
作者 王爱民 祖元刚 《沈阳农业大学学报》 CAS CSCD 2004年第3期220-222,共3页
研究了白桦(Betulaplatyphylla)不同方向功能叶片(东向和南向)以净光合速率(Pn)为主要特征的光合作用日进程响应及净光合速率对环境因子的强度响应。结果表明,白桦的净光合速率与光合有效辐射(PAR)极显著相关(P<0.01),与气温(Ta)显... 研究了白桦(Betulaplatyphylla)不同方向功能叶片(东向和南向)以净光合速率(Pn)为主要特征的光合作用日进程响应及净光合速率对环境因子的强度响应。结果表明,白桦的净光合速率与光合有效辐射(PAR)极显著相关(P<0.01),与气温(Ta)显著相关(P<0.05),而与大气相对湿度(RH)不相关。并首次提出了植物功能叶片“微环境”的概念。 展开更多
关键词 白桦 微环境因子 光合响应 东向叶片 南向叶片
在线阅读 下载PDF
免疫细胞在糖尿病大血管病变中的作用 被引量:8
19
作者 杨婵 杨嫱妃 +3 位作者 谢子妍 鄢然 蔡雪琴 谢春光 《中国比较医学杂志》 CAS 北大核心 2019年第3期98-102,共5页
糖尿病大血管病变呈低度炎症状态,免疫炎症反应引发的持续性血管损伤是其病理基础。免疫细胞失衡导致大血管区域免疫炎症微环境紊乱是免疫炎性中心反应,但其确切病理机制尚未明确,故笔者通过综述以巨噬细胞、淋巴细胞、树突状细胞、肥... 糖尿病大血管病变呈低度炎症状态,免疫炎症反应引发的持续性血管损伤是其病理基础。免疫细胞失衡导致大血管区域免疫炎症微环境紊乱是免疫炎性中心反应,但其确切病理机制尚未明确,故笔者通过综述以巨噬细胞、淋巴细胞、树突状细胞、肥大细胞等免疫细胞与糖尿病大血管病变的相关性,简要分析免疫细胞在糖尿病大血管病变发生发展中可能的机制。 展开更多
关键词 糖尿病大血管病变 免疫细胞 综述 免疫炎症反应 大血管区域免疫炎症 微环境紊乱
在线阅读 下载PDF
Combretastatin A-1 phosphate, a microtubulin inhibitor, induces hepatocellular carcinoma cells and tumor-associated macrophage apoptosis by uncoupling tubulin and p-AKT
20
《中国药理学通报》 CAS CSCD 北大核心 2015年第B11期234-234,共1页
Combretastatin A-1 phosphate (CA1P) is a tubulin polymerization inhibitor that binds to the colchicine- binding site of tubulin and shows potential anti-tumor activity to acute myelocytic leukemia as reported. We de... Combretastatin A-1 phosphate (CA1P) is a tubulin polymerization inhibitor that binds to the colchicine- binding site of tubulin and shows potential anti-tumor activity to acute myelocytic leukemia as reported. We demon- strated that CA1P also showed an outstanding anti-cancer effect on hepatocellular carcinoma (HCC) in vivo and in vitro. As determined by DCFH-DA dye and Western blot, CA1P induced ROS accumulation and apoptosis in HepG2 cells with the down-regulation of Mcl-1. Additonal western blot and immunofluorescence assays further indi- cated that CA1P inhibited Wnt/β-catenin pathway through GSK-3β activition with an increasing of Mcl phosphoryl- ation and subsequent degradation mediated by tubulin-dynactin p l50-AKT signaling pathway axis. Apoptosis of HepG2 cells induced by CA1P was reversed by the GSK-3β inhibitor ( CHIR-99021 ). Furthermore, determined by immunohistochemistry of an orthotopic HCC tumor model, CA1P showed a significantly effect on tumor associated macrophage (TAM) apoptosis in vitro and eliminated TAM in tumor microenviroment in vivo, while the infiltration of Treg cells and expression of TGF-β were also altered. Adoptive transfer of macrophages reinstated tumor growth treated by CA1P. These results indicated that CA1P presented potent potential on the regulation of hepatocellular carcinoma cells and TAMs, and also revealed a novel anti-HCC mechanism of CA1P, which acted on both cancer cells and tumor microenvironment. The findings would be beneficial for exploring new application of anti-microtubu- lar drugs on oncotherapy. 展开更多
关键词 COMBRETASTATIN A-1 PHOSPHATE hepatocellular carcinoma wnt/β-catenin TUMOR associated macro-phage TUMOR microenvironment anti-microtubular drug
在线阅读 下载PDF
上一页 1 2 下一页 到第
使用帮助 返回顶部