检索结果-南通市图书馆

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

MCA协效膨胀阻燃LDPE泡沫材料的研究

现代塑料加工应用 2016年第4期28卷 19-22页

作者：刘云冯钠高杨李蕾杨亮大连工业大学纺织与材料工程学院辽宁大连116034

以木质素为炭源、聚磷酸铵(APP)为酸源和气源、三聚氰胺尿酸盐(MCA)为协效阻燃剂、低密度聚乙烯(LDPE)为基体材料,采用共混塑炼-热压法制备膨胀阻燃LDPE泡沫材料,研究MCA对膨胀阻燃LDPE泡沫材料结构与性能的影响。结果表明:MCA加入使膨... 详细信息

以木质素为炭源、聚磷酸铵(APP)为酸源和气源、三聚氰胺尿酸盐(MCA)为协效阻燃剂、低密度聚乙烯(LDPE)为基体材料,采用共混塑炼-热压法制备膨胀阻燃LDPE泡沫材料,研究MCA对膨胀阻燃LDPE泡沫材料结构与性能的影响。结果表明:MCA加入使膨胀阻燃LDPE泡沫材料的刚性和模量有所提高,同时提高了膨胀阻燃发泡体系的阻燃效率。当APP与MCA的质量比为6∶5时,极限氧指提高到28.1%,垂直燃烧达到FV-0级,无滴落现象,700℃残炭量提高到32.3%,燃烧后炭层结构光滑致密。

关键词：低密度聚乙烯三聚胺氰尿酸盐木质素聚磷酸铵泡沫材料阻燃性

马铃薯转录因子StFBH3对非生物逆境胁迫的响应分析

在线全文

学校读者我要写书评

暂无评论

作物学报 2025年第1期51卷 247-259页

作者：宋倩娜宋慧洋李京昊段永红梅超冯瑞云山西农业大学农学院山西太谷030801 山西省农业科学院作物科学研究所山西太原030031

bHLH (basic helix-loop-helix)作为植物界第二大类转录因子,在植物应对环境胁迫响应中起着重要的调控作用。探究马铃薯(Solanum tuberosum L.) bHLH家族基因功能将为马铃薯改良和育种提供一定的理论依据。本研究克隆了马铃薯StFBH3基因... 详细信息

bHLH (basic helix-loop-helix)作为植物界第二大类转录因子,在植物应对环境胁迫响应中起着重要的调控作用。探究马铃薯(Solanum tuberosum L.) bHLH家族基因功能将为马铃薯改良和育种提供一定的理论依据。本研究克隆了马铃薯StFBH3基因(Gene ID:102582309),利用qPCR技术分析了不同逆境胁迫下StFBH3基因表达模式,结果表明, StFBH3基因在马铃薯根和叶中的表达量较高,且该基因的表达受渗透、高盐和脱落酸(abscisic acid, ABA)诱导;以过表达StFBH3基因的马铃薯试管苗为材料,在分别含有不同浓度甘露醇(mannitol)、naCl和ABA的MS培养基中,过表达StFBH3马铃薯株系的叶绿素含量显著高于野生型,根长显著长于野生型。在干旱和高盐处理下,土壤栽培的过表达马铃薯株系较野生型表现较强的耐受性,叶片相对含水量、叶绿素含量和过氧化物歧化酶(SOD)活性显著高于野生型。qPCR分析发现,干旱和盐胁迫处理下相关基因(KAT1)的表达量在过表达马铃薯株系中较野生型显著降低。以上结果表明, StFBH3基因可能在马铃薯对渗透、干旱和高盐等胁迫响应中起正向调控作用。本研究也为StFBH3基因在马铃薯中的生物学功能深入理解提供一定的参考依据。

关键词：马铃薯 StFBH3 转录因子逆境胁迫

维普期刊数据库博看期刊

同方期刊数据库

Synergistic effects of particulate matter(PM_10) and SO_2 on human non-small cell lung cancer A549 via ROS-mediated NF-κB activation

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2015年第5期27卷 146-153页

作者： yang yun Rui Gao Huifeng Yue Guangke Li na Zhu nan Sang College of Environment and Resource Research Center of Environment and Health Shanxi University

Since a real atmospheric scenario usually represents a system involving multiple pollutants, air pollution studies typically focused on describing adverse effects associated with exposure to individual pollutants cannot reflect actual health risk. Particulate matter（PM10） and sulfur dioxide（SO2） are two major pollutants derived from coal combustion processes and co-existing in coal-smoke air pollution, but their potentially synergistic toxicity remains elusive thus far. In this study, we investigated the cytotoxic responses of PM10 and SO2, singly and in binary mixtures, using human non-small cell lung cancer A549 cells, followed by clarifying the possible mechanisms for their interaction. The results indicated that the concomitant treatment of PM10 and SO2 at low concentrations led to synergistic injury in terms of cell survival and apoptosis occurrence, while PM10 and SO2 alone at the same concentrations did not cause damage to the cells. Also, radical oxygen species（ROS） production followed by nuclear factor kappa B（NF-κB） activation was involved in the above synergistic cytotoxicity, which was confirmed by the repression of the actions by an ROS inhibitor（naC）. This implies that assessment of health risk should consider the interactions between ambient PM and gaseous copollutants.

关键词： PM10 SO2 Synergistic toxicity ROS NF-κB

Soy Isoflavone and Its Effect to Regulate Hypothalamus and Peripheral Orexigenic Gene Expression in Ovariectomized Rats Fed on A High-Fat Diet

在线全文

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 2010年第1期23卷 68-75页

作者： yun-BO ZHANG yang ZHANG LI-na LI XIN-YU ZHAO XIAO-LIN na Department of Environmental Hygiene Department of Environmental Hygiene Toxicology Nutrition and Food Hygiene College of Public Health Harbin Medical University Harbin 150086 Heilongjiang China

Objective To explore the effect of soy isoflavone on obesity in the light of hypothalamus and peripheral orexigenic gene regulation. Methods Fifty-four female rats were randomly assigned to 6 groups： one sham-operated group （SHAM）, one ovariectomized （OVX） control group, three OVX groups fed with 400 ppm （L-SI）, 1 200 ppm （M-SI） and 3 600 ppm （H-SI） isoflavone respectively, and one OVX group receiving 0.45 ppm diethylstilbestrol （EC）. All rats were allowed to take high-fat diet for 4 weeks. Some neuropeptides were measured by RT-PCR. These neuropeptides included NPY, pro-opiomelanocortin （POMC）, cocaine and amphetamine regulated transcript （CART）, orexin, melanin-concentrating hormone （MCH）, ting hormone precursor （P-MCH）, ghrelin, and leptin. Results Compared with the OVX control group, the body weight and food intake in the H-S1 group were reduced significantly and there was a significant dose-dependent manner in the 3 isoflavone groups. The results of RT-PCR showed that the NPY level in the 3 isoflavone groups was significantly increased and the POMC/CART gene expression decreased significantly in rats＇ hypothalamus compared with that in the OVX control group. However, the expression of orexin, MCH and P-MCH had no change. The peripheral grelin mRna expression was higher in the 3 isoflavone groups, while leptin gene expression in the fat was not consistent. Conclusions This research showed that isoflavone could prevent obesity induced by high-fat diet and ovariectomy through regulating hypothalamus and peripheral orexigenic gene expressions associated with food intake.

关键词： Isoflavone Hypothalamus Orexigenic gene express Obesity

Two New Iridoid Glucosides from Clerodendrum serratum

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2000年第3期11卷 231-234页

作者： Hui yang Bei JIANG Zhi na yun Pin GUO Han Dong SUN Laboratory of Phytochemistry Kunming Institute of BotanyThe Chinese Academy of SciencesKunming 650204 Chemistry Department of the College of Life Science and Chemistry Yunnan UniversityKunming 650091 Chemistry Group Kunming Medical CollegeKunming 650031

Two new iridoid glucosides, serratoside A and serratoside B, were isolated from the aerial parts of Clerodendrum serratum var. amplexifolium Moldenke. Their structures were elucidated by spectral and chemical methods.

关键词： Clerodendrum serratum Verbenaceae iridoid glucoside serratoside A serratoside B

Fabrication of Intracranial Vascular Nitinol Alloy Stents with Improved Mechanical Property and Endothelialization Function

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2022年第12期35卷 2069-2081页

作者： yangyang Yan na Li Feng Guo Anhua Wu Wei Jin Rui yang yun Bai Xing Zhang Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China College of Life Science and Engineering Shenyang UniversityShenyang 110044China Department of Neurosurgery The First Affi liated Hospital of China Medical UniversityShenyang 110001China

Intracranial vascular stenting has been widely used for ischemic ***,there are complication risks with stent implantation,such as poor wall apposition,stent migration,thromboembolism and stent restenosis,due to the mismatched radial force and conformability of the stents."Therefore,a novel intracranial vascular nitinol stent was fabricated in order to improve mechanical property and endothelialization *** bending moment of the stents was calculated to be 0.346 N mm,which shows improved *** radial force of the stents evaluated by the flat plate test was0.0112 N/mm,within the range of the commercially available stent force(0.0065-0.0116 N/mm).Furthermore,the TyrIle-Gly-Ser-Arg(YIGSR)peptide derived from laminin was grafted onto the stent surfaces to promote endothelialization on vascular stents evaluated by the proliferation,adhesion and migration of human umbilical vein endothelial cells in *** nitinol stents with improved mechanical property and endothelialization function are expected to reduce the recurrence risk of ischemic stroke after implantation.

关键词： Nitinol stents Conformability Radial force Endothelialization Intracranial stenosis treatment

Optimal time for mesenchymal stem cell transplantation in rats with myocardial infarction

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第8期9卷 630-637页

作者： Chen-yang JIANG Chun GUI Ai-na HE Xin-yang HU Jie CHEN yun JIANG Jian-an WANG Department of Cardiology Sir Run Run Shaw Hospital School of Medicine Zhejiang University Hangzhou 310016 China Department of Cardiology the Second Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310009 China Department of Cardiology the First Affiliated Hospital Zhejiang Chinese Medical University Hangzhou 310006 China

Background:Bone marrow mesenchymal stem cell (MSC) transplantation is a promising strategy in the treatment of myocardial infarction (MI). However, the time for transplanting cells remains controversial. The aim of this study was to find an optimal time point for cell transplantation. Methods: MSCs were isolated and cultured from Sprague-Dawley (SD) rats. MI model was set up in SD rats by permanent ligation of left anterior descending coronary artery. MSCs were directly injected into the infarct border zone at 1 h, 1 week and 2 weeks after MI, respectively. Sham-operated and MI control groups received equal volume of phosphate buffered saline (PBS). At 4 weeks after MI, cardiac function was assessed by echocardiography; vessel density was analyzed on hematoxylin-eosin stained slides by light microscopy; the apoptosis of cardiomyocytes was evaluated by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay; the expressions of proteins were analyzed by Western blot. Results: MSC transplantation improved cardiac function, reduced the apoptosis of cardiomyocytes and increased vessel density. These benefits were more obvious in 1-week group than in 1-h and 2-week groups. There are more obvious in-creases in the ratio of bcl-2/bax and the expression of vascular endothelial growth factor (VEGF) and more obvious decreases in the expression of cleaved-caspase-3 in 1-week group than those in other two groups. Conclusion: MSC transplantation was beneficial for the recovery of cardiac function. MSC transplantation at 1 week post-MI exerted the best effects on increases of cardiac function, anti-apoptosis and angiogenesis.

关键词： Mesenchymal stem cells (MSCs) Transplantation Myocardial infarction (MI) Apoptosis

An Explicit Counter-example for the Shephard Problem of Convex Bodies in R^n

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2015年第12期31卷 1941-1950页

作者： yun Wei XIA Chun na ZENG School of Mathematics and Statistics Southwest University College of Mathematics Science Chongqing Normal University

Comparing the volume of the projection body of a double cone and that of the projection body of a ball,we give an explicit counter-example for the Shephard problem of convex bodies in R^n（n≥3）and an affirmative ans... 详细信息

关键词： The Shephard problem projection bodies double cone

Effects of arsenic on seed germination and physiological activities of wheat seedlings

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2007年第6期19卷 725-732页

作者： LI Chun-xi FENG Shu-li SHAO yun JIANG Li-na LU Xu-yang HOU Xiao-li College of Life Sciences Henan Normal University Xinxiang 453007 China

The effects of arsenic （As） were investigated on seed germination, root and shoot length and their biomass and some other factors to elucidate the toxicity of As. The results showed low concentrations of As （0-1 mg/kg） stimulated seed germination and the growth of root and shoot, however, these factors all decreased gradually at high concentrations of As （5-20 mg/kg）. The contents of O2^-, MDA, soluble protein and peroxidase （POD） activity all increased with increasing As concentrations. Soluble sugar content, ascorbate peroxidase （APX）, and superoxide dismutase （SOD） activities decreased at low concentrations of As, and increased at high concentrations of As. While acetylsalicylic acid （ASA） and chlorophyll contents, catalase （CAT） activity displayed increasing trend when the concentrations of As was lower than 1 mg/kg, and then decreasing trend. By polyacrylamide gel electrophoresis （PAGE）, As induced the expression of POD isozymes of wheat seedlings. As induced the expression of CAT isozymes but inhibited the expression of SOD isozymes of wheat seedlings at concentrations lower than 1 mg/kg. However, As inhibited the expression of CAT isozymes but induced the expression of SOD isozymes at concentrations higher than 5 mg/kg. The results indicated As could exert harmfulness in the early development stage of wheat at inappropriate concentrations.

关键词： arsenic wheat germination physiological activities