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毛竹的生物性特征及种植策略 被引量:4
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作者 谢招烟 《吉林农业(下半月)》 2018年第10期81-81,共1页
毛竹适应环境性强、产量高、生长周期短,是我国非常重要的经济类植物。毛竹还具有较强的生态效益,在吸收噪音污染、防止泥石流、防风固沙等方面发挥着重要作用。本文主要分析毛竹的生物性特征及种植策略,旨在为毛竹种植管理提供理论指导。
关键词 毛竹 生物性特征 种植
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新疆甜菜湿腐型根腐病病原的鉴定 被引量:6
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作者 赵思峰 王钦英 +1 位作者 李晖 李国英 《石河子大学学报(自然科学版)》 CAS 2002年第4期289-291,共3页
1996~ 1999年从新疆各主要甜菜产区采集湿腐型甜菜根腐病样 91个 ,从中分离获得 81个腐霉菌分离物 ,根据形态特征、生物学特性和菌体可溶性蛋白电泳测定 ,将其鉴定为 3个种 :瓜果腐霉 (Pythiumaphanidermatum)、简囊腐霉 (Pythiummonos... 1996~ 1999年从新疆各主要甜菜产区采集湿腐型甜菜根腐病样 91个 ,从中分离获得 81个腐霉菌分离物 ,根据形态特征、生物学特性和菌体可溶性蛋白电泳测定 ,将其鉴定为 3个种 :瓜果腐霉 (Pythiumaphanidermatum)、简囊腐霉 (Pythiummonospermum)和Pythiumspp .。经致病性测定表明 ,这 3种腐霉菌是造成新疆甜菜根腐病的主要病原。 展开更多
关键词 新疆甜菜 湿腐型根腐病 病原鉴定 形态特征 生物性特征 瓜果腐霉
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Induced Expression of Cytochrome P450 CYP305 B1V1 Gene in Different Tissues of Wild Mulberry Silkworm(Bombyx mandarina) 被引量:6
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作者 路爱成 卫正国 +1 位作者 李兵 沈卫德 《Agricultural Science & Technology》 CAS 2009年第2期54-58,共5页
[ Objective] The aim of this study was to investigate effects of various inducers on the expression of cytochrome P450 CYP305 B1 V1 Gene in different tissues of wild mulberry silkworm. [ Method] Referring to the mRNA ... [ Objective] The aim of this study was to investigate effects of various inducers on the expression of cytochrome P450 CYP305 B1 V1 Gene in different tissues of wild mulberry silkworm. [ Method] Referring to the mRNA sequence of CYP305 B1 V1 Gene published in GenBank for wild mulberry silkworm, one pair of primers was designed, and the expression of cytochrome P450 CYP305 B1 V1 Gene in different tissues of wild mulberry silkworm treated by NaF, rutin, cypermethrin and ecdysone was also analyzed by the semi - quantitative RT - PCR. Furthermore, homology comparison and phylogenetic analysis for amino acid sequences of this gene were studied. [ Result] Rutin, cypermethrin and NaF had effects on the expression of P450 CYP305 B1 V1 Gene in different tissues of wild mulberry silkworm, while ecdysone had no significant effect. Homology comparison for amino acids indicated that the amino acid sequence of this gene was the most similar to that of CYP305 B1 gene in Bombyx mori with 100% amino acid identity, and highly similar to those of Tribolium casmneum CYP305A1, Apis mellifera CYP305A1, Drosophi- la melanogaster CYP305A1, Anopheles gambiae CYP305A2and Culex pipiens quinquefasciatus CYP2LI. [ Conclusion] CYP305 B1 V1 Gene of wild mulberry silkworm is likely to mainly take part in the metabolism of exogenous compounds, which is of great significance for revealing the function of cytochrome P450 and the metabolic mechanism of different drugs. 展开更多
关键词 Wild mulberry silkworm CYP305B1V1 INDUCE EXPRESSION Phylogenetic analysis
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Status of urban vegetation in Guangzhou City 被引量:12
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作者 管东生 陈玉娟 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第3期249-252,共4页
According to a survey for the urban vegetation of Guangzhou, urban vegetation has a significantly difference from natural vegetation because of intense human impacts. The research was conducted in a synthetic survey f... According to a survey for the urban vegetation of Guangzhou, urban vegetation has a significantly difference from natural vegetation because of intense human impacts. The research was conducted in a synthetic survey for soil, species di-versity, roadside trees and ecological function of urban vegetation in Guangzhou City. The results showed that: (1) soil densi-ties of urban roadside and park forests were higher than mean density of natural forest soil. The pH values of soil in urban roadside were higher too, and the content of organic matter and the concentration of nitrogen were lower. (2) Species diversity of urban vegetation was lower. The most number of species was only 16 species in tree layers of urban forest. (3) Tree growth was limited by narrow space in high-density urban area, where the trees with defects and disorders were common. (4) Com-paring with mature natural forests, the productivity of urban vegetation was lower. The effect of urban vegetation on balance of carbon and oxygen were influenced by the low primary production of urban vegetation. Therefore, the growth condition for urban vegetation should be improved. Biodiversity, primary production and ecological function should be increased for urban vegetation in order to improve urban eco-environment. 展开更多
关键词 Urban vegetation STATUS Human impact
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探析蛀干害虫杨干象人工防治技术
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作者 刘长利 《农业与技术》 2018年第2期195-195,共1页
杨干象又被称之为杨干象鼻虫,属于一种蛀干害虫,在杨柳科植物中,常出现的一类病虫害类型,并且,在我国分布较为广泛。杨干象对于杨柳科植物的幼树危害性极大,幼树常因其蛀食而树干折断、死亡,一旦大面积发生病虫害,将对我国林木业生产以... 杨干象又被称之为杨干象鼻虫,属于一种蛀干害虫,在杨柳科植物中,常出现的一类病虫害类型,并且,在我国分布较为广泛。杨干象对于杨柳科植物的幼树危害性极大,幼树常因其蛀食而树干折断、死亡,一旦大面积发生病虫害,将对我国林木业生产以及生态效益造成严重性的影响。由此可见,加大对杨干象病虫害的防治工作探究,有针对性地采取科学有效的防治方法进行防治,对保障各地林业大力发展意义重大。 展开更多
关键词 杨干象 生物性特征 人工防治 措施
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试论鲜花小苗快速培育技术
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作者 李叶红 《低碳世界》 2014年第02X期30-31,共2页
桂花为木樨科木樨属常绿阔叶乔木,是我国的传统名贵花卉。桂花原产于我国,现四川、云南、广东、广西、湖北省均分布有野生桂花,淮河以南可露地栽培,淮河以北以盆栽为主。在我们日常生活中,桂花的用途也很多,比如泡桂花茶、制桂花... 桂花为木樨科木樨属常绿阔叶乔木,是我国的传统名贵花卉。桂花原产于我国,现四川、云南、广东、广西、湖北省均分布有野生桂花,淮河以南可露地栽培,淮河以北以盆栽为主。在我们日常生活中,桂花的用途也很多,比如泡桂花茶、制桂花糕等等,为此,我们应该了解它的生物性特征、繁殖技术和管理技术。 展开更多
关键词 桂花小苗 生物性特征 繁殖技术 管理技术
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Study on Biological Characters of Asparagus macowanii Baker. 被引量:1
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作者 刘方农 彭世逞 刘联仁 《Agricultural Science & Technology》 CAS 2012年第11期2351-2354,共4页
Asparagus macowanfi Baker, is a climbing herbaceous foliage species in genus Asparagus of Liliaceae, This paper summarized its multiple uses, morphologi- cal characteristics, biological habit, reproduction methods, ma... Asparagus macowanfi Baker, is a climbing herbaceous foliage species in genus Asparagus of Liliaceae, This paper summarized its multiple uses, morphologi- cal characteristics, biological habit, reproduction methods, management after cultiva- tion, prevention and control of pests and disease, as well as harvest and grading, with the objective to provide references for the exploitation and utilization of As- paragus macowanii Baker. 展开更多
关键词 Asparagus macowanii Baker Biological Characters Multiple uses
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Cymolomia hartigiana (Saxesen,1840)(Lepidoptera: Tortricidae) at-tacking to Abies nephrolepis Max. New to Daxing'anling,Heilongji-ang,China
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作者 边凤奎 李成德 张立志 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第1期67-68,J003,共3页
An Olethreutine speciesCymolomia hartigiana (Saxesen, 1840), attacking toAbies nephrolepis Max., is reported for the first time from Daxing'anling, Heilongjiang, China. The morphological characteristics are briefl... An Olethreutine speciesCymolomia hartigiana (Saxesen, 1840), attacking toAbies nephrolepis Max., is reported for the first time from Daxing'anling, Heilongjiang, China. The morphological characteristics are briefly re-described with illustrations. Also its damage and biology are noted. Key words Systematics - Lepidoptera - Tortricidae - Cymolomia - Daxing'anling - China CLC number Q969.429.2 - S763.3 Document code A Foundation item: This study was carried out under the financial support by KOSEF (Korea Science & Engineering Foundation) with the program of “Korea and China Young Scientist Exchange Program” (2002–2003).Biography: *BYUN Bong-Kya (1963-), male, Ph.D., Researcher in Korea National Arboretum, Korea.Responsible editor: Chai Ruihai 展开更多
关键词 SYSTEMATICS LEPIDOPTERA TORTRICIDAE Cymolomia Daxing'anling China
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Do deposed adult male Sichuan snub-nosed monkeys Rhinopithecus roxellana roam as solitary bachelors or continue to interact with former band members? 被引量:2
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作者 Dapeng ZHAO Baoguo LI 《Current Zoology》 SCIE CAS CSCD 北大核心 2009年第3期235-237,共3页
Dispersal patterns exhibited by group-living animals play an important role in individual reproductive success and survival, as well as population and social dynamics (Greenwood, 1980; Isbell and van Vuren, 1996; Kap... Dispersal patterns exhibited by group-living animals play an important role in individual reproductive success and survival, as well as population and social dynamics (Greenwood, 1980; Isbell and van Vuren, 1996; Kappeler and van Schaik, 2002). Dispersing individuals may emigrate voluntarily, or they may be forcibly evicted by other individuals (Pusey and Packer, 1987; Clobert et al. , 2001 ). One cause of individual dispersal is when an extra-group male compels another male to leave a group of females. This phenomenon has been well documented in primates, especially Old World monkey species ( e.g. Colobus vellerosus : Saj and Sicotte, 2005 ; Erythrocebus patas : Ohsawa, 2003 ; Macaca fascicularis : van Noordwiik and van Schaik, 2001). 展开更多
关键词 Deposed males All male groups One-male groups Behavioral strategy
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Molecular and in vitro Characterization of Field Isolates of Bovine Herpesvirus-1 被引量:4
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作者 Julian Ruiz-Saenz Jairo Jaime +1 位作者 Gloria Ramirez Victor Vera 《Virologica Sinica》 SCIE CAS CSCD 2012年第1期26-37,共12页
Bovine Herpesvirus-1 (BoHV-1) is distributed worldwide and is a major pathogen in cattle, being the causal agent of a variety of clinical syndromes. The aim of this study was to isolate and to characterize (molecular ... Bovine Herpesvirus-1 (BoHV-1) is distributed worldwide and is a major pathogen in cattle, being the causal agent of a variety of clinical syndromes. The aim of this study was to isolate and to characterize (molecular and biological characterization) BoHV-1 from 29 immunosuppressed animals. It was possible to obtain 18 isolates, each from a different animal, such as from the respiratory and reproductive tracts. In some cases the cytopathic effect was visible 12 hours post-inoculation, and became characteristic after 36-48 hours. Biological characteristics were evaluated and compared with Iowa and Colorado-1 reference strains, and differences were found in plaque size, virus titer measured by TCID50 and PFU/mL, and one step virus curves. These results showed that some isolates had a highly virulent-like behavior in vitro, compared to the reference strains, with shorter eclipse periods, faster release of virus into the supernatants, and higher burst size and viral titer. There were no differences in glycoprotein expression of BoHV-1 isolates, measured by Western blot on monolayers. Moreover, using restriction endonucleases analysis, most of the viruses were confirmed as BoHV-1.1 and just one of them was confirmed as BoHV-1.2a subtype. These findings suggest that some wild-type BoHV-1 isolates could be useful as seeds to develop new monovalent vaccines. 展开更多
关键词 Bovine herpesvirus 1 Genital infection Respiratory infection Latent infection
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Invasion and spreading of Cabomba caroliniana revealed by RAPD markers
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作者 金孝锋 丁炳扬 +1 位作者 高树琴 姜维梅 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2005年第4期406-413,共8页
Applying randomly amplified polymorphic DNA (RAPD), the genetic variation of Cabomba caro- liniana Gray (cabomba or fanwort), a new alien plant in China, was analyzed in this paper. Total 143 bands, in- cluding 47 pol... Applying randomly amplified polymorphic DNA (RAPD), the genetic variation of Cabomba caro- liniana Gray (cabomba or fanwort), a new alien plant in China, was analyzed in this paper. Total 143 bands, in- cluding 47 polymorphic bands, were amplified from 23 primers in 20 samples. The sampling distance was large, but its genetic diversity was low. The main results were that: (1) Cabomba, which grew and dispersed mainly in fragment, was an abundant and dominant species in freshwater, and its main dispersal mechanism was vegetative reproduction. (2) Cabomba was originally introduced into China as an aquarium submerged plant. Somehow, those discarded cabomba became invasive species in the areas of Hangzhou, Shanghai, and Meicheng, and other places. (3) Although the level of genetic diversity in cabomba was low, their rapid dispersion and propagation could seriously harm to local aquatic community. Therefore, specific measure should be used to control cabomba from uncontrolled spreading and damage to local vegetation communities. 展开更多
关键词 Cabomba caroliniana (cabomba) alien species biological invasion genetic diversity RAPD-PCR
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Covariation between personalities and individual differences in coping with stress:Converging evidence and hypotheses 被引量:6
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作者 Claudio CARERE Doretta CARAMASCHI Tim W. FAWCETT 《Current Zoology》 SCIE CAS CSCD 北大核心 2010年第6期728-740,共13页
In the past decade there has been a profusion of studies highlighting covariation between individual differences in stress physiology and behavioural profiles, here called personalities. Such individual differences in... In the past decade there has been a profusion of studies highlighting covariation between individual differences in stress physiology and behavioural profiles, here called personalities. Such individual differences in ways of coping with stress are relevant both in biomedicine, since different personalities may experience a different stress and disease vulnerability, and in behavioural ecology, since their adaptive value and evolutionary maintenance are the subject of debate. However, the precise way in which individual stress differences and personalities are linked is unclear. Here we provide an updated overview of this covariation across different species and taxa, consider its functional significance and present working hypotheses for how behavioural and physiological responses to stress might be causally linked, affecting life-history traits such as dispersal and life-span [Current Zoology 56 (6): 728-740, 2010]. 展开更多
关键词 Animal personality Coping style Agression Stress response CORTICOSTERONE GLUCOCORTICOIDS Natural selection Fitness evolution
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Seasonal Suspended Particles Distribution Patterns in Western South Yellow Sea Based on Acoustic Doppler Current Profiler Observation 被引量:1
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作者 LI Jianchao LI Guangxue +5 位作者 XU Jishang QIAO Lulu DONG Ping DING Dong LIU Shidong SUN Pingkuo 《Journal of Ocean University of China》 SCIE CAS 2015年第3期385-398,共14页
An Acoustic Doppler Current Profiler (ADCP) observation site was set up in the Western South Yellow Sea from 2012 to 2013 to study the local suspended particle matters (SPM) distribution pattern. The SPM concentra... An Acoustic Doppler Current Profiler (ADCP) observation site was set up in the Western South Yellow Sea from 2012 to 2013 to study the local suspended particle matters (SPM) distribution pattern. The SPM concentration could be semi-quantitatively represented by backscatter intensity (Sv), converted by the echo intensity (E/) of ADCP. Results show two types of SPM in the water column: the quasi-biological SPM and quasi-mineral SPM. The quasi-biological SPM mainly exists in summer half year and is con- centrated above the thermocline. It has periodically diurnal variations with high concentration at night and low concentration in the daytime. The quasi-mineral SPM is located in lower part of the water column, with similar relation to monthly tidal current variation all year round. However, the daily quasi-mineral SPM distribution patterns vary between summer and winter half year. The sunlight is thought to be the origin factor leading to the diurnally vertical motion of the biological features, which might cause the diurnal Sv variation. Unlike in winter half year when tidal current is relatively single driving force of the monthly SPM pattern, the high speed current near the thermocline is also responsible for the concentration of quasi-mineral SPM in summer half year. The sediment input difference between summer and winter half year contribute to the varied daily variation of quasi-mineral SPM with re-suspended SPM ir~ winter and sediments from Yellow Sea Mud Area (YSMA) in summer. The seasonal variations in hydrodynamics, water structure and heavy-wind incidents are the primary factors influencing the differential seasonal SPM distribution patterns. 展开更多
关键词 the South Yellow Sea backscatter intensity suspended particle matters seasonal distribution patterns diurnal periodicvariation
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Microbial Community Characteristics in a Degraded Wetland of the Yellow River Delta 被引量:28
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作者 WANG Zhen-Yu XIN Yuan-Zheng +3 位作者 GAO Dong-Mei LI Feng-Min J. MORGAN XING Bao-Shan 《Pedosphere》 SCIE CAS CSCD 2010年第4期466-478,共13页
Five different sites with a soluble salt gradient of 3.0-17.7 g kg^-1 dry soil from the coast to the inland were selected, and the microbial population size, activity and diversity in the rhizospheres of five common p... Five different sites with a soluble salt gradient of 3.0-17.7 g kg^-1 dry soil from the coast to the inland were selected, and the microbial population size, activity and diversity in the rhizospheres of five common plant species and the adjacent bulk soils (non-rhizosphere) were compared in a degraded wetland of the Yellow River Delta, Shandong Province, China to study the effects of soil environment (salinity, seasonality, depth, and rhizosphere) on microbial communities and the wetland's ecological function, thus providing basic data for the bioremediation of degraded wetlands. There was a significant negative linear relationship between the salinity and the total number of microorganisms, overall microbial activity, or culturable microbial diversity. Salinity adversely affected the microbial community, and higher salinity levels resulted in smaller and less active microbial communities. Seasonal changes were observed in microbial activity but did not occur in the size and diversity. The microbial size, activity and diversity decreased with increasing soil depth. The size, activity and diversity of culturable microorganisms increased in the rhizospheres. All rhizospheres had positive effects on the microbial communities, and common seepweed had the highest rhizosphere effect. Three halophilic bacteria (Pseudomonas mendocina, Burkholderia glumae, and Acinetobacter johnsonii) were separated through BIOLOG identification, and common seepweed could be recommended for bioremediation of degraded wetlands in the Yellow River Delta. 展开更多
关键词 microbial activity microbial diversity RHIZOSPHERE SALINITY soil microorganisms
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Genetic Improvement and Biological Characteristic Analysis of Dwarf Abortive TypeJaponicaCMS Lines with Wide Compatibility 被引量:1
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作者 SONG Xin-wei LIN Jian-rong WU Ming-guo 《Agricultural Science & Technology》 CAS 2011年第7期980-984,996,共6页
From the view of methodology for genetic improvement ofJaponicacytoplasmic male sterile(CMS) lines,we introduced the breeding process of the dwarf-abortive type(DA type)JaponicaCMS line Chunjiang 95A with wide compati... From the view of methodology for genetic improvement ofJaponicacytoplasmic male sterile(CMS) lines,we introduced the breeding process of the dwarf-abortive type(DA type)JaponicaCMS line Chunjiang 95A with wide compatibility,and further investigated the biological characteristics of the DA type Chunjiang 95A and its isonuclear alloplasmic CMS line Dian-I type Chunjiang 95A.The results show that DA type Chunjiang 95A is a japonicalinous CMS line and mainly typical abortive,which is better in fertility stability than stained abortive typeJaponica CMS lines.The DA type Chunjiang 95A is featured with high stigma exsertion,good flowering habit,high outcrossing rate and wide compatibility.Its recoverability differs from stained abortive typeJaponicaCMS lines.Moreover,we discussed genetic improvement of the typical abortive type JaponicaCMS lines and the application prospects of heterosis. 展开更多
关键词 Wide compatibility Japonica rice CMS line Stigma exsertion BREEDING
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Kinship alters the effects of forced cohabitation on body weight,mate choice and fitness in the rat-like hamster Tscheskia triton
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作者 Xiaoping RAO Jian-Xu ZHANG +1 位作者 Dingzhen LIU Lin CONG 《Current Zoology》 SCIE CAS CSCD 北大核心 2009年第1期41-47,共7页
It has been documented that social isolation imparts deleterious effects on gregarious rodents species, but caging in group imparts such effects on solitary rodents. This study was attempted at examining how kinship t... It has been documented that social isolation imparts deleterious effects on gregarious rodents species, but caging in group imparts such effects on solitary rodents. This study was attempted at examining how kinship to affect body weight, behavioral interaction, mate choice and fitness when we caged male and female rat-like hamsters Tscheskia triton in pair, a solitary species. We found that females paired with nonsibling males became heavier than the females paired with sibling males, but both agonistic and amicable behavior between paired males and females did not differ between sibling and nonsibling groups. This indicated that kinship might reduce females' obesity in response to forced cohabitation, and dissociation might exist between physiological and behavioral responses. Furthermore, binary choice tests revealed that social familiarity between either siblings or nonsiblings decreased their investigating time spent in opposite sex conspeeifie of cage mates and/or their scents as compared with those of nonmates, suggesting effects of social association on mate and kin selection of the hamsters. On the other side, both females and males caged in pair with siblings show a preference between unfamiliar siblings or their scents and the counterparts of nonsiblings after two month separation, indicating that the kin recognition of the hamsters might also rely on phenotype matching. In addition, cohabitation (or permanent presence of fathers) elicited a lower survival of pups in nonsibling pairs than sibling pairs, but did not affect litter size, suggesting that kinship affects fitness when housing male and female ratlike hamsters together. Therefore, inbreeding might be adapted for rare and endangered animals. 展开更多
关键词 Tscheskia triton INBREEDING NEPOTISM FITNESS Kin recognition Mate choice
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Survey of Plant Community Characteristics in Bamenwan Mangrove of Wenchang City
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作者 YANG Zhongyang XUE Yang +3 位作者 SU Shaofeng WANG Xiaoyan LIN Zhipan CHEN Hongjin 《Journal of Landscape Research》 2018年第2期93-96,共4页
According to natural conditions and vegetation distribution characteristics of Wenchang Bamenwan Mangrove Forest, sample plots were set up to investigate plant community characteristics in this area, and to explore th... According to natural conditions and vegetation distribution characteristics of Wenchang Bamenwan Mangrove Forest, sample plots were set up to investigate plant community characteristics in this area, and to explore the diversity characteristics of different subareas and calculate importance values of various tree species in the study area. According to the investigation, there are 48 plant species of 42 genera and 28 families in Bamenwan Mangrove Forest, including 29 tree species of 24 genera and 17 families. Among the tree species, those on the top 5 in the importance value list are Hibiscus tiliaceus, Bruguiera sexangula, Lumnitzera littorea, Rhizophora apiculata, Xylocarpus granatum. There are 3 shrub species of 3 genera and 3 families, including Atalantia buxifolia, Lantana camara and Streblus asper. And there are 16 herbal species of 16 genera and 11 families, including Acrostichum aureum, Vernonia cinerea, Acanthus ilicifolius, Alocasia macrorrhiza, Synedrel a nodiflora, Gynura japonica and etc.. Diversity of the mangrove in different areas varies greatly, Shannon-Wiener index and richness index of semi-mangrove forest are both higher than those of other 3 mangrove forests. Bamenwan Mangrove Forest is characterized by diversified species and complex structures, but the community diversity is unevenly distributed because of the interventions from many factors. More human efforts are suggested to enhance the mangrove protection, so as to enrich the community diversity. 展开更多
关键词 Bamenwan of Wenchang City Mangrove Importance value DIVERSITY
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Dynamic genetic features of eukaryotic plankton diversity in the Nakdong River estuary of Korea
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作者 LEE Jee Eun CHUNG Ik Kyo LEE Sang-Rae 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第4期844-857,共14页
Estuaries are environments where freshwater and seawater mix and they display various salinity profiles.The construction of river barrages and dams has rapidly changed these environments and has had a wide range of im... Estuaries are environments where freshwater and seawater mix and they display various salinity profiles.The construction of river barrages and dams has rapidly changed these environments and has had a wide range of impacts on plankton communities.To understand the dynamics of such communities,researchers need accurate and rapid techniques for detecting plankton species.We evaluated the diversity of eukaryotic plankton over a salinity gradient by applying a metagenomics tool at the Nakdong River estuary in Korea.Environmental samples were collected on three dates during summer and autumn of 2011 at the Eulsukdo Bridge at the mouth of that river.Amplifying the 18 S rDNA allowed us to analyze 456 clones and 122 phylotypes.Metagenomic sequences revealed various taxonomic groups and cryptic genetic variations at the intra-and inter-specific levels.By analyzing the same station at each sampling date,we observed that the phylotypes presented a salinity-related pattern of diversity in assemblages.The variety of species within freshwater samples reflected the rapid environmental changes caused by freshwater inputs.Dinophyceae phylotypes accounted for the highest proportion of overall diversity in the seawater samples.Euryhaline diatoms and dinoflagellates were observed in the freshwater,brackish and seawater samples.The biological data for species composition demonstrate the transitional state between freshwater and seawater.Therefore,this metagenomics information can serve as a biological indicator for tracking changes in aquatic environments. 展开更多
关键词 18S rDNA clone library METAGENOME ESTUARY salinity gradient
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Spacial Distribution Characteristics, Activity and Degradation Capability of the Biofilm in Integrated Vertical-flow Constructed Wetland 被引量:1
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作者 J. Li X.X. Mao Z.B. Wu 《Journal of Environmental Science and Engineering》 2010年第10期57-62,共6页
The spacial distribution characteristics, activity and degradation capability of the biofilm in integrated vertical-flow constructed wetland were investigated. Results showed that the biofilm widely distributed in the... The spacial distribution characteristics, activity and degradation capability of the biofilm in integrated vertical-flow constructed wetland were investigated. Results showed that the biofilm widely distributed in the substrate of integrated vertical-flow constructed wetland and mainly in the 0-10 cm top layer where the activity ofdehydrogenase of the biofilm was also higher than that of other layers. The water quality could also affect the activity of the biofilm, for the TF(1,3,5-Triphenylformazan) amount reduced by the biofim incubated in water of the higher eutrophication was larger, too. The PCP (pentachlorophenol) removal rate by the substrate with biofilm was 1.5 times that without biofilm. In total, the biofilm of the down-flow chamber appeared larger biomass, higher dehydrogenase activity and stronger degradation capability of organic contamination than that in up-flow chamber and it was the major place for removal of the organic matters in waste water. 展开更多
关键词 Integrated vertical-flow constructed wetland BIOFILM DISTRIBUTION activity of dehydrogenase degradation capacity
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Clinical and biological characteristics of colorectal cancer with familial predisposition
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作者 吴保平 张亚历 +2 位作者 周殿元 高春芳 赖卓胜 《Journal of Medical Colleges of PLA(China)》 CAS 2001年第2期90-93,共4页
Objective:To evaluatethemicrosatelliteinstability(MSI),expressionof mismatchrepair(MMR)gene(hMLH1,hMSH2)andproliferationkineticsincolorectalcancer(CRC)withfamilialpredisposition.Method:Forty-sixcasesof CRC were studie... Objective:To evaluatethemicrosatelliteinstability(MSI),expressionof mismatchrepair(MMR)gene(hMLH1,hMSH2)andproliferationkineticsincolorectalcancer(CRC)withfamilialpredisposition.Method:Forty-sixcasesof CRC were studiedusingsilverstainingpolymerasechainreaction-singlestrandconformation polymorphism(PCR-SSCP)technique,streptavidin-peroxidase(SP)immunohistochemicalmethodand flowcyto-metry.Results:In CRCpatientswithfamilialpredisposition,theMSI-positiveratewas higherthanin sporadicCRC(P<0.05).FamilialpredispositionandpositiveMSIwerestronglyrelatedto earlyageof canceronset,theproclivity for proximalcoloniccancer,poordifferentiatedandextracolorectalnmalignancies(P<0.01,P<0.05).Theincidence of negativeexpressionof hMLH1intumortissueandhMLH1,hMSH2innormalcolorectaltissueswassignificantly higher(P<0.05).Thenegativeexpressionof hMLH1togetherwithhMSH2was relatedwithpositiveMSI(P<0.05).InMSI-positiveCRCcells,theproliferationcellnucleusantigen(PCNA)expression,proliferationindexandS-phase cellsdecreasedobviously(P<0.01,P<0.05).Conclusion:In CRCwithfamilialpredisposition,MSI mightbe an importantcontributor.Therateof hMLH1andhMSH2mutationincreasedintumorandnormaltissue,andtheproli-ferationactivityof theircancercellwaslower. 展开更多
关键词 COLORECTALCANCER familialpredisposition microsatelliteinstability mismatchrepairgene genemutation GENEEXPRESSION CELLPROLIFERATION
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