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Heterogeneity in the regenerative abilities of central nervous system axons within species:why do some neurons regenerate better than others? 预览
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作者 William Rodemer Jianli Hu +1 位作者 Michael E.Selzer Michael I.Shifman 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第6期996-1005,共10页
Some neurons,especially in mammalian peripheral nervous system or in lower vertebrate or in vertebrate central nervous system(CNS)regenerate after axotomy,while most mammalian CNS neurons fail to regenerate.There is a... Some neurons,especially in mammalian peripheral nervous system or in lower vertebrate or in vertebrate central nervous system(CNS)regenerate after axotomy,while most mammalian CNS neurons fail to regenerate.There is an emerging consensus that neurons have different intrinsic regenerative capabilities,which theoretically could be manipulated therapeutically to improve regeneration.Population-based comparisons between"good regenerating"and"bad regenerating"neurons in the CNS and peripheral nervous system of most vertebrates yield results that are inconclusive or difficult to interpret.At least in part,this reflects the great diversity of cells in the mammalian CNS.Using mammalian nervous system imposes several methodical limitations.First,the small sizes and large numbers of neurons in the CNS make it very difficult to distinguish regenerating neurons from non-regenerating ones.Second,the lack of identifiable neurons makes it impossible to correlate biochemical changes in a neuron with axonal damage of the same neuron,and therefore,to dissect the molecular mechanisms of regeneration on the level of single neurons.This review will survey the reported responses to axon injury and the determinants of axon regeneration,emphasizing non-mammalian model organisms,which are often under-utilized,but in which the data are especially easy to interpret. 展开更多
关键词 axonal regeneration identifiable neurons intrinsic factors LAMPREY Mauthner cell Müller cell neuronal death non-mammalian model organisms spinal cord injury zebrafish
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青岛近海潮间带生物体重金属含量及评价 预览
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作者 刘阳 相杰友 张凡顺 《河北渔业》 2019年第11期32-36,共5页
研究调查了青岛近海潮间带生物体重金属含量并采用单因子污染指数法进行了污染评价。研究表明,青岛近海潮间带调查生物中重金属含量差异较大,不同生物对重金属元素富集具有偏好性,长牡蛎中Cu及Zn的含量最高,锈凹螺中Pb、As、Hg及Cr含量... 研究调查了青岛近海潮间带生物体重金属含量并采用单因子污染指数法进行了污染评价。研究表明,青岛近海潮间带调查生物中重金属含量差异较大,不同生物对重金属元素富集具有偏好性,长牡蛎中Cu及Zn的含量最高,锈凹螺中Pb、As、Hg及Cr含量最高,史氏背尖贝中Cd的含量最高;单因子污染指数发现青岛近海潮间带生物体中Cu、Pb、Zn、Cd及Cr处于正常背景水平,而Hg及As在个别站位采集的生物出现轻污染、污染或者重污染情况,尤其是As;同其他海区同物种或者近缘物种比较发现,砷的含量要高于其他海区,其他重金属含量偏低或者相近。 展开更多
关键词 青岛近海潮间带 生物体 重金属
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Fluorescence imaging of Cu(Ⅰ) in endoplasmic reticulum of live cells and tissue
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作者 Xiaowen Yan X. Chris Le 《中国科学:化学英文版》 SCIE EI CAS CSCD 2019年第7期887-888,共2页
Copper (Cu) is an essential element to living organisms. The redox activity of Cu gives rise to redox cycling reactions between Cu^2+ and Cu^+. Organisms harness this redox cap? ability for their biological functions ... Copper (Cu) is an essential element to living organisms. The redox activity of Cu gives rise to redox cycling reactions between Cu^2+ and Cu^+. Organisms harness this redox cap? ability for their biological functions by tightly regulating copper homeostasis in the processes of cellular uptake, intracellular transport, protein loading and storage [1]. 展开更多
关键词 endoplasmic reticulum Copper (Cu) LIVING ORGANISMS
Toxicity and mechanisms of action of titanium dioxide nanoparticles in living organisms
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作者 Jing Hou Luyao Wang +4 位作者 Chunjie Wang Songlin Zhang Haiqiang Liu Shiguo Li Xiangke Wang 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第1期40-53,共14页
Titanium dioxide nanoparticles(TiO2 NPs) are one of the most widely used nanomaterials in the consumer products, agriculture, and energy sectors. Their large demand and widespread applications will inevitably cause da... Titanium dioxide nanoparticles(TiO2 NPs) are one of the most widely used nanomaterials in the consumer products, agriculture, and energy sectors. Their large demand and widespread applications will inevitably cause damage to organisms and ecosystems. A better understanding of TiO2 NP toxicity in living organisms may promote risk assessment and safe use practices of these nanomaterials. This review summarizes the toxic effects of TiO2 NPs on multiple taxa of microorganisms, algae, plants, invertebrates, and vertebrates. The mechanism of TiO2 NP toxicity to organisms can be outlined in three aspects: The Reactive Oxygen Species(ROS)produced by TiO2 NPs following the induction of electron–hole pairs; cell wall damage and lipid peroxidation of the cell membrane caused by NP-cell attachment by electrostatic force owing to the large surface area of TiO2 NPs; and TiO2 NP attachment to intracellular organelles and biological macromolecules following damage to the cell membranes. 展开更多
关键词 TiO2 nanoparticles PARTICLE size EXPOSURE OXIDATIVE stress LIVING ORGANISMS
钙华生物沉积作用研究进展与展望
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作者 汪智军 殷建军 +1 位作者 蒲俊兵 袁道先 《地球科学进展》 CAS CSCD 北大核心 2019年第6期606-617,共12页
弄清钙华生物沉积作用有助于更好地理解钙华微岩相结构和地球化学特征的气候环境指示意义。总结和综述了与钙华沉积相关的生物群落、生物成因钙华微岩相结构、钙华生物沉积作用过程及其对钙华地球化学特征影响的研究进展,并展望了未来... 弄清钙华生物沉积作用有助于更好地理解钙华微岩相结构和地球化学特征的气候环境指示意义。总结和综述了与钙华沉积相关的生物群落、生物成因钙华微岩相结构、钙华生物沉积作用过程及其对钙华地球化学特征影响的研究进展,并展望了未来的研究重点。细菌、藻类和苔藓等广泛参与到钙华沉积中,形成了许多不同类型的孔隙结构、晶体结构和纹层结构。生物沉积过程主要包括:①生物生长扰动水流使得CO2逸出;②代谢作用(如光合作用)过程诱导碳酸钙沉积;③"表面控制"过程影响晶体成核及生长。生物沉积作用驱动了元素的迁移转化,对沉积水体和钙华地球化学特征具有重要影响。钙华在地球生物学研究中具有重要潜力,未来需要加强现代钙华沉积中的物理化学和生物过程相互作用机制及其各自贡献的量化研究,以便准确地解译钙华沉积记录。 展开更多
关键词 钙华 生物群落 生物成因结构 生物沉积过程 地球化学特征
生草栽培对龙眼果园土壤理化性质和微生物学性状的影响
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作者 潘介春 徐石兰 +7 位作者 丁峰 张振镜 周煜棉 王金英 徐炯志 邓英毅 程夕冉打 莫云川 《中国果树》 北大核心 2019年第6期59-64,共6页
为优选出南方龙眼果园适宜的生草品种,在‘四季蜜’龙眼果园分别在行间套种假地豆、白花三叶草、鼠茅草、阔叶丰花草和自然生草,幵以清耕为对照,研究套种不同草种对龙眼果园土壤理化性质及生物学性状的影响。结果表明:果园行间生草能提... 为优选出南方龙眼果园适宜的生草品种,在‘四季蜜’龙眼果园分别在行间套种假地豆、白花三叶草、鼠茅草、阔叶丰花草和自然生草,幵以清耕为对照,研究套种不同草种对龙眼果园土壤理化性质及生物学性状的影响。结果表明:果园行间生草能提高土壤含水量,降低土壤pH值;生草刜期,各生草处理0~15 cm土层土壤中全氮、全磷含量下降,钙、镁含量上升,15~30cm土层中的全氮含量上升,生草对土壤营养元素的影响随着土层的加深而逐渐下降;生草栽培总体来看能够提高土壤中微生物的数量;各生草处理的土壤微生物量碳、氮含量均显著高于清耕;各生草处理土壤中β-葡萄糖苷酶、氨肽酶和磷酸二脂酶活性高于清耕,阔叶丰花草处理土壤中β-葡萄糖苷酶、磷酸二脂酶活性显著高于其他草种,鼠茅草处理土壤中氨肽酶含量最高。龙眼果园生草能增加土壤中微生物数量,提高碳、氮含量和磷循环相兲酶活性,改良土壤环境,生草栽培刜期消耗土壤中矿物质元素,在生长刜期要及时给肥。综合各生草草种对土壤理化性质和生物学性状的影响,以白花三叶草为佳,适宜在南方龙眼果园推广。 展开更多
关键词 龙眼 果园生草 土壤 理化性质 生物学性状
Coastal Organisms Trapped in 99-Million-Year-Old Amber
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作者 《中国科学院院刊:英文版》 2019年第2期123-124,共2页
Most amber inclusions are organisms that lived in the forest. It is very rare to find sea life trapped in amber. However, an international research group led by Prof. WANG Bo from the Nanjing Institute of Geology and ... Most amber inclusions are organisms that lived in the forest. It is very rare to find sea life trapped in amber. However, an international research group led by Prof. WANG Bo from the Nanjing Institute of Geology and Palaeontology of the Chinese Academy of Sciences (NIGPAS) reported the first known ammonite trapped in amber in a study in PNAS published on May 13. 展开更多
关键词 ORGANISMS rare NANJING
The Most Primitive Extant Ancestor of Organisms and Discovery of Definitive Evolutionary Equations Based on Complete Genome Structures 预览
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作者 Kenji Sorimachi 《自然科学期刊(英文)》 2018年第9期338-369,共32页
Evolutionary divergence has been characterized based on morphological and molecular features using rationale based on Darwin’s theory of natural selection. However, universal rules that govern genome evolution have n... Evolutionary divergence has been characterized based on morphological and molecular features using rationale based on Darwin’s theory of natural selection. However, universal rules that govern genome evolution have not been identified. Here, a simple, innovative approach has been developed to evaluate biological evolution initiating the origin of life: whole genomes were divided into several fragments, and then differences in normalized nucleotide content between nucleotide pairs were compared. Intramolecular nucleotide differences in complete mitochondrial genomes reflect evolutionary divergence. The values of (G – C), (G – T), (G – A), (C – T), (C – A) and (T – A) reflect biological evolution, and these values except for (G – C) and (T – A) change inversely to positive from negative along biological evolution of bacterial genomes. More highly evolved organisms, such as primates and birds, seem to have greater levels of (C – T) in mitochondria. Based on nucleotide content structures, Monosiga brevicollis mitochondria may be the most primitive extant ancestor of the species examined here. The two normalized nucleotide contents are universally expressed by a linear regression line, (X – Y)/(X + Y) = a(X – Y) + b, where X and Y are nucleotide contents and (a) and (b) are constants. The value of (G + C), (G + A), (G + T), (C + A), (C + T) and (A + T) was ~0.5. Plotting (X – Y)/(X + Y) against X/Y showed a logarithmic function (X – Y)/(X + Y) = a lnX/Y + b, where (a) and (b) are constant. Nucleotide content changes are expressed by a definitive equation, (X – Y) ≈ 0.25 ln(X/Y). 展开更多
关键词 PRIMITIVE ORGANISMS EVOLUTIONARY EQUATIONS
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Introducing an antibiotic stewardship program in a pediatric center in China
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作者 Zhi-Gang Zhang Fei Chen Jian-Zhong Chen 《世界儿科杂志(英文版)》 2018年第3期274-279,共6页
Background This study aimed to investigate the eff ect of antibiotic stewardship programs (ASP) on reducing antimicrobial resistance rate, antibiotics consumption and multi-drug resistance bacterial infections in the ... Background This study aimed to investigate the eff ect of antibiotic stewardship programs (ASP) on reducing antimicrobial resistance rate, antibiotics consumption and multi-drug resistance bacterial infections in the pediatric patients. Methods This study was carried out in the Pediatric Center of a tertiary hospital of Shandong Province, China. The study duration was separated into two periods according to introduction of ASP (began from April 2011). Before intervention: from April 2009 to March 2011;after intervention: from April 2012 to March 2014. The consumption of antibiotics, defi ned daily dose (DDD), isolation of multidrug-resistant organisms (MDRO) and resistance rate of antibiotics were analyzed and compared between the two study periods. Results Total antibiotics consumption (DDDs) reduced from 56,725 in 2011 to 31,380 in 2014;antibiotic use density (AUD) reduced from 93.8 to 43.5;mean (± SD) antibiotic costs per patient (per quarter) decreased from 637 (± 29) RMB to 462 (± 49) RMB;and the mean total drug consumption (g)/DDD (DDDs) for inpatients decreased from 90.4 (± 3.3) to 56.4 (± 9.5). Multidrug-resistant microorganisms isolation reduced signifi cantly from 463 (20.0) to 216 (6.9%). Resistance rate of general spectrum antibiotics reduced remarkably after intervention. The proportion of patients colonized or infected with Carbapenems-resistantAcinetobacter baumannii was correlated with DDDs of carbapenem. Conclusions Implementation of ASP leads to reduced medical expense, decrease of improper and abuse of antibiotics, and reduced antibiotics resistance rate and MDRO isolation. Continuous eff orts to improve antibiotic use are required. 展开更多
关键词 ANTIMICROBIAL resistance Antibiotic STEWARDSHIP PROGRAM (ASP) Defined daily dose (DDD) Isolation of MULTIDRUG-RESISTANT ORGANISMS (MDRO)
The Original Organism Assemblages and Kerogen Carbon Isotopic Compositions of the Early Paleozoic Source Rocks in the Tarim Basin, China 预览
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作者 HU Guang MENG Qingqiang +5 位作者 WANG Jie Tengger XIE Xiaomin LU Longfei LUO Houyong LIU Wenhui 《地质学报:英文版》 SCIE CAS CSCD 2018年第6期2297-2309,共13页
Original organisms are the biological precursors of organic matter in source rocks.Original organisms in source rocks are informative for oil-source rock correlation and hydrocarbon potential evaluation,especially for... Original organisms are the biological precursors of organic matter in source rocks.Original organisms in source rocks are informative for oil-source rock correlation and hydrocarbon potential evaluation,especially for source rocks which have high-over level of thermal maturity.Systematic identification of original organism assemblages of the Lower Paleozoic potential source rocks and detailed carbon isotopic composition of kerogen analyses were conducted for four outcrop sections in the Tarim basin.Results indicated that the original organism assemblages of the lower part of the Lower Cambrian were composed mainly of benthic algae,whereas those of the Upper Cambrian and the Ordovician were characterized by planktonic algae.Kerogen carbon isotopic data demonstrated that the δ 13 C kerogen values of source rocks dominated by benthic algae are lower than ?34‰,whereas the δ 13 C kerogen values of source rocks dominated by planktonic algae are higher than ?30‰ in general.We tentatively suggested that the carbon species those are utilized by algae and the carbon isotopic fractionation during photosynthesis are the major controls for the δ 13 C kerogen values in the Lower Paleozoic source rocks in the Tarim basin.Correlating the δ 13 C values of oils exploited in the Tarim basin,the original organism assemblages,and δ 13 C kerogen values of source rocks,it implied that the Lower Paleozoic oils exploited in the Tarim basin should be sourced from the source rocks with original organism assemblages dominated by planktonic algae,and the hydrocarbon sourced from the Cambrian benthic algae should be of great exploration potential in future.Original organism assemblages in source rocks can provide important clues for oil-source rocks correlation,especially for the source rocks with high thermal maturity. 展开更多
关键词 Tarim basin the Lower Paleozoic source rock ORIGINAL organisms KEROGEN carbon isotopes
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Management of bacterial and fungal infections in end stage liver disease and liver transplantation:Current options and future directions 预览
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作者 Elda Righi 《世界胃肠病学杂志:英文版》 SCIE CAS 2018年第38期4311-4329,共19页
Patients with liver cirrhosis are susceptible to infections due to various mechanisms,including abnormalities of humoral and cell-mediated immunity and occurrence of bacterial translocation from the intestine.Bacteria... Patients with liver cirrhosis are susceptible to infections due to various mechanisms,including abnormalities of humoral and cell-mediated immunity and occurrence of bacterial translocation from the intestine.Bacterial infections are common and represent a reason for progression to liver failure and increased mortality.Fungal infections,mainly caused by Candida spp.,are often associated to delayed diagnosis and high mortality rates.High level of suspicion along with prompt diagnosis and treatment of infections are warranted.Bacterial and fungal infections negatively affect the outcomes of liver transplant candidates and recipients,causing disease progression among patients on the waiting list and increasing mortality,especially in the early posttransplant period.Abdominal,biliary tract,and bloodstream infections caused by Gram-negative bacteria[e.g.,Enterobacteriaceae and Pseudomonas aeruginosa(P.aeruginosa)]and Staphylococcus spp.are commonly encountered in liver transplant recipients.Due to frequent exposure to broad-spectrum antibiotics,invasive procedures,and prolonged hospitalizations,these patients are especially at risk of developing infections caused by multidrug resistant bacteria.The increase in antimicrobial resistance hampers the choice of an adequate empiric therapy and warrants the knowledge of the local microbial epidemiology and the implementation of infection control measures.The main characteristics and the management of bacterial and fungal infections in patients with liver cirrhosis and liver transplant recipients are presented. 展开更多
关键词 LIVER cirrhosis LIVER transplant RECIPIENTS BACTERIAL INFECTIONS Fungal INFECTIONS MULTIDRUG resistant organisms MANAGEMENT
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六溴环十二烷异构体的毒理效应及其在生物体内的代谢转化过程研究进展
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作者 耿金瑶 王莹莹 《环境化学》 CSCD 北大核心 2017年第12期2558-2566,共9页
六溴环十二烷(hexabromocyclododecane,HBCD)是一种溴化阻燃添加剂,在建筑、纺织、电子生产等工业中被广泛应用,造成环境污染的同时,对人体健康也存在危害,属于持久性有机污染物(POPs),引起各国学者的广泛关注.工业级的HBCD主要由(... 六溴环十二烷(hexabromocyclododecane,HBCD)是一种溴化阻燃添加剂,在建筑、纺织、电子生产等工业中被广泛应用,造成环境污染的同时,对人体健康也存在危害,属于持久性有机污染物(POPs),引起各国学者的广泛关注.工业级的HBCD主要由(±)-α-HBCD,(±)-β-HBCD和(±)-γ-HBCD构成,本文总结了近年来关于HBCD对映异构体及非对映异构体的研究,对比几种异构体的毒理效应、在不同生物体内的吸收、转化、代谢的过程及其代谢机理,发现几种异构体对不同种生物体甚至同一种生物体不同组织部位的作用均存在很大差异,提出了进一步研究的主要方向. 展开更多
关键词 六溴环十二烷 毒理效应 转化 代谢 生物体
不同类型VFA对反硝化同步脱氮除磷的影响 预览
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作者 邹海明 王艳 《化学工程》 CSCD 北大核心 2017年第10期12-16,26共6页
为探究不同类型VFA(乙酸和丙酸)对反硝化同步脱氮除磷的影响,采用厌氧/缺氧富集驯化反硝化同步脱氮除磷微生物(DPAO),利用电子扫描显微镜(SEM)观察富集后微生物特征,并通过批次实验考察2种污泥的厌氧碳吸收、磷释放和缺氧硝酸盐... 为探究不同类型VFA(乙酸和丙酸)对反硝化同步脱氮除磷的影响,采用厌氧/缺氧富集驯化反硝化同步脱氮除磷微生物(DPAO),利用电子扫描显微镜(SEM)观察富集后微生物特征,并通过批次实验考察2种污泥的厌氧碳吸收、磷释放和缺氧硝酸盐消耗、磷吸收情况。结果表明:以乙酸和丙酸为VFA富集DPAO是可行的;乙酸系统中DPAO以短杆菌为主,而丙酸系统中DPAO以球菌为主,反映了DAPO的多样性特征;乙酸系统中,厌氧碳利用效率0.14 mg/mg(COD)和释磷速率3.5 mg/(g·h)(MLSS)、缺氧氮利用效率0.9 mg/mg(N)和吸磷速率2.3 mg/(g·h)(MLSS),明显高于丙酸系统中的相应参数值0.10 mg/mg(COD),2.7 mg/(g·h)(MLSS),0.7 mg/mg(N),1.7 mg/(g·h)(MLSS);乙酸系统呈现出典型的反硝化同步脱氮除磷特征,而丙酸系统除反硝化同步脱氮除磷外,还存在异氧菌的反硝化脱氮行为。 展开更多
关键词 反硝化同步脱氮除磷 微生物 挥发性脂肪酸 碳源 电镜扫描
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较场尾海域重金属污染评价及人体暴露风险评估 预览 被引量:2
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作者 赵子科 陈春亮 +2 位作者 杨国欢 谢群 柯盛 《广东海洋大学学报》 CAS 2017年第4期61-68,共8页
于2015年11月和2016年3月调查了较场尾海域海洋环境状况,以海水水质标准、综合污染指数和潜在生态风险指数、目标危险系数来评价较场尾海域海水、沉积物及生物体重金属的污染现状和摄入健康风险。结果表明:两个航次海水均有个别重金... 于2015年11月和2016年3月调查了较场尾海域海洋环境状况,以海水水质标准、综合污染指数和潜在生态风险指数、目标危险系数来评价较场尾海域海水、沉积物及生物体重金属的污染现状和摄入健康风险。结果表明:两个航次海水均有个别重金属含量超标,其中2015年11月份航次重金属Pb、Hg超标,站位超标率分别为40%和20%,2016年3月份航次重金属Cu、Pb、Hg超标,站位超标率分别为5%、20%和5%,较场尾海域表层海水重金属浓度基本呈现由北向南逐渐递减的趋势;较场尾海域表层沉积物主要受到Cu、Pb、Cr、Hg的污染,其中5站的Cr和15站的Hg均超过海洋沉积物质量二类标准,Cu和Cr的站位超标率为16.7%,Pb和Hg的站位超标率为8.3%,站位综合污染指数以5站6.02为最大,潜在生态风险指数以15站65.14为最大;较场尾附近海域的重金属污染主要来自附近的工业厂区和燃煤电厂;较场尾海域所捕获到的鱼、虾、头足类目标危险系数之和由大到小为:鱼(0.132)>头足(0.062)>虾(0.012),均不存在人体摄入健康风险。 展开更多
关键词 重金属 海水 沉积物 生物体 风险评估
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某核电站运行前环境辐射本底调查中生物体(90)Sr的监测 被引量:1
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作者 娄海林 卢瑛 +6 位作者 文富平 徐旭涛 刘雷 涂兴明 侯术果 邵明刚 李加兴 《中国辐射卫生》 2017年第6期692-694,701共4页
目的获取某核电站运行前生物体中(90)Sr放射水平,为评价核电站运行期间对周围环境中生物的影响提供本底数据。方法依据国家相关标准规定的分析监测方法。结果陆生植物,家禽、淡水鱼,海洋生物中(90)Sr活度浓度分别为:26.8~1845.0 m... 目的获取某核电站运行前生物体中(90)Sr放射水平,为评价核电站运行期间对周围环境中生物的影响提供本底数据。方法依据国家相关标准规定的分析监测方法。结果陆生植物,家禽、淡水鱼,海洋生物中(90)Sr活度浓度分别为:26.8~1845.0 m Bq/kg,36.4~815.0 m Bq/kg,10.2~534.0 m Bq/kg。结论该核电站周围生物中(90)Sr活度浓度属于正常的本底放射性水平。 展开更多
关键词 核电站 生物体 (90)Sr放射性水平
有机抑芽剂对烤烟抑芽效果的影响 预览 被引量:2
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作者 何楷 伍优 +5 位作者 余传兴 叶征宇 孟源 黄纯杨 郑维毅 李章海 《安徽农业科学》 CAS 2017年第10期36-38,共3页
[目的]研究开发环境友好型烟草抑芽剂。[方法]以打顶不抹杈为阴性对照,以常规抑芽剂氟节胺乳油为阳性对照,对有机生物抑芽剂的抑芽效果进行对比研究。[结果]有机生物抑芽剂可以显著拓展烟株顶部第1、2片烟叶的叶面积;第1片叶的增幅最大,... [目的]研究开发环境友好型烟草抑芽剂。[方法]以打顶不抹杈为阴性对照,以常规抑芽剂氟节胺乳油为阳性对照,对有机生物抑芽剂的抑芽效果进行对比研究。[结果]有机生物抑芽剂可以显著拓展烟株顶部第1、2片烟叶的叶面积;第1片叶的增幅最大,达432.27 cm^2,第2片叶增幅为214.87 cm^2。有机生物抑芽剂抑芽效果明显,且有效性较常规抑芽剂持续。在施药后21 d,有机生物抑芽剂的抑芽率为72.56%,比常规抑芽剂高3.39百分点;最终抑芽效果略好于常规抑芽,为88.33%,比它高0.18百分点。有机生物抑芽剂可以优化烤后烟叶的内在化学成分,提升评吸质量。相较常规抑芽剂,它可以使烤后烟叶总糖达到27.81%,增加0.61百分点;还原糖达24.43%,增加1.30百分点;总氮降至1.85%,减少0.07百分点;烟碱降至2.41%,降低0.34百分点;K提至2.57%,增加0.35百分点;氯含量降至0.27%,减少0.01百分点;与此同时,它还可以提高烤后烟的香气质、香气量,降低杂气及刺激性,增强透发性、柔细度、甜度及余味,即使用有机生物抑芽剂进行抑芽可明显改善烤后烟叶的评吸质量。[结论]采用菜油、酒精、烟焦油配制而成的有机生物抑芽剂可为生产开发推广环境友好型抑芽剂提供依据。 展开更多
关键词 有机生物 氟节胺 抑芽剂 烤烟
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青海海晏县生物体中硒的环境效应评价 预览 被引量:1
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作者 马强 张亚峰 +2 位作者 田兴元 姬丙艳 马风娟 《中国矿业》 北大核心 2016年第S1期274-275,313共3页
本文通过多目标调查手段研究了区内牧草、生物机体和骨骼中硒的地球化学特征,评价了硒所产生的环境生态效应。结果认为区内牧草、动物机体和骨骼中硒含量均小于正常值,具有低硒风险;低硒的环境地球化学特征对当地动物体正常生长已造成... 本文通过多目标调查手段研究了区内牧草、生物机体和骨骼中硒的地球化学特征,评价了硒所产生的环境生态效应。结果认为区内牧草、动物机体和骨骼中硒含量均小于正常值,具有低硒风险;低硒的环境地球化学特征对当地动物体正常生长已造成一定的影响,导致局部发生白肌病病症,当地牧民应加强对动物体外源硒的补充。 展开更多
关键词 生物体 地球化学特征
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嵌合抗原受体修饰的T细胞的临床应用及研究进展 被引量:5
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作者 陈骋 李宗海 《肿瘤》 CAS CSCD 北大核心 2016年第3期351-357,共7页
嵌合抗原受体(chimeric antigen receptor,CAR)修饰T细胞(CAR-T细胞)技术是近年来发展非常迅速的一种过继性免疫治疗技术。其通过基因改造技术,将能识别肿瘤相关抗原(tumor associate antigen,TAA)的单链抗体和能促进T细胞活化的... 嵌合抗原受体(chimeric antigen receptor,CAR)修饰T细胞(CAR-T细胞)技术是近年来发展非常迅速的一种过继性免疫治疗技术。其通过基因改造技术,将能识别肿瘤相关抗原(tumor associate antigen,TAA)的单链抗体和能促进T细胞活化的信号传递结构域融合表达于自体T细胞的表面,从而赋予该T细胞以肿瘤靶向的杀伤活性和持久扩增的能力。从该技术被发明以来,CAR的设计已从仅包含单一CD3ζ信号传递结构域的第一代CAR发展为加入了CD28和CD137(4-1BB)等共刺激分子信号传递结构域的第二和第三代CAR,并均已开展了多项临床试验。其中,针对CD19的CAR-T细胞在治疗血液肿瘤中取得的成果尤为引人瞩目,但该技术同时也存在脱靶效应和细胞因子释放综合征等临床应用风险。本文将就CAR-T细胞技术在恶性肿瘤临床免疫治疗中的应用、存在的问题及可能的解决方案作一全面的阐述,以便于使广大研究人员能更全面地了解CAR-T细胞技术的发展及应用情况。 展开更多
关键词 肿瘤 基因重排 T淋巴细胞 生物 基因修饰 免疫疗法
石墨烯和氧化石墨烯的生物体毒性研究进展 预览 被引量:3
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作者 李婷 张超智 +1 位作者 沈丹 袁阳 《南京大学学报:自然科学版》 CAS CSCD 北大核心 2016年第2期235-243,共9页
由于石墨烯功能材料具有优异的电子、光学等特性,已经被广泛应用在光伏电池、航空航天、生物传感、疾病诊断、细菌抑制、抗病毒材料等领域.随着其广泛的研究和应用,石墨烯和氧化石墨烯衍生物开始在空气、水和土壤中出现.这类物质粒径很... 由于石墨烯功能材料具有优异的电子、光学等特性,已经被广泛应用在光伏电池、航空航天、生物传感、疾病诊断、细菌抑制、抗病毒材料等领域.随着其广泛的研究和应用,石墨烯和氧化石墨烯衍生物开始在空气、水和土壤中出现.这类物质粒径很小,容易进入生物体,与组织、细胞、细胞器和蛋白质等生物大分子相互作用,导致组织或细胞的功能紊乱.然而目前关于石墨烯及其衍生物的生物体毒性研究还不多.主要综述了近几年石墨烯和氧化石墨烯衍生物对生物体的影响,分析石墨烯相关材料对生物体作用的毒性机理,阐述其生物危害性,为石墨烯类产业发展所需要防范的环境风险提供基础信息,最后提出了对石墨烯及其衍生物进行定量研究生物毒性的重要性,以及含石墨烯类垃圾的处理方法. 展开更多
关键词 石墨烯 氧化石墨烯 毒性 生物体
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石墨烯健康风险研究现状及展望 被引量:4
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作者 孙寒 冯雷雨 陈银广 《生物化学与生物物理进展》 SCIE CAS CSCD 北大核心 2015年第1期5-15,共11页
石墨烯是一种新型的二维碳纳米材料,由于具有优异的电子、光学、机械等特性,已经被广泛应用于电子器件、复合材料、能源储存等领域.近年来,石墨烯在生物医药领域崭露头角,其在诸如生物传感器、细胞成像、药物输运、抗菌材料等方面的广... 石墨烯是一种新型的二维碳纳米材料,由于具有优异的电子、光学、机械等特性,已经被广泛应用于电子器件、复合材料、能源储存等领域.近年来,石墨烯在生物医药领域崭露头角,其在诸如生物传感器、细胞成像、药物输运、抗菌材料等方面的广泛应用,为生物医药技术带来了突破,也为人体健康带来了福音.然而,随着石墨烯以不同途径进入人们的生活,其对人体及其他生物体的安全构成潜在威胁,引发的健康风险正受到广泛关注.本文从石墨烯对生物体的影响及其同生物体的相互作用方面入手,综述了近年来石墨烯健康风险的研究进展,并且总结归纳了人体抵御石墨烯健康风险的途径及机制,最后指出了未来石墨烯健康风险方面的研究方向. 展开更多
关键词 石墨烯 生物体 相互作用 健康风险 生物医药 毒理学
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