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Biological Characteristics of Trehalose and Its Protective Effect on Food Fermentation Starters during Lyophilization
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作者 Yuhong YANG Yangdi ZHANG 《Agricultural Biotechnology》 CAS 2023年第4期45-48,共4页
This paper reviewed the unique biological function of trehalose and its mechanism of stabilizing biological macromolecules and the research progress in the protective effect of trehalose on lactic acid bacteria fermen... This paper reviewed the unique biological function of trehalose and its mechanism of stabilizing biological macromolecules and the research progress in the protective effect of trehalose on lactic acid bacteria fermentation starters during lyophilization in food production.The application of trehalose in food industry was prospected. 展开更多
关键词 TREHALOSE biological characteristics LYOPHILIZATION
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In vitro growth, differentiation and biological characteristics of neural stem cells 被引量:20
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作者 Meijiang Yun Lianzhong Wang +1 位作者 Yongcai Wang Xiaolian Jiang 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第4期364-367,共4页
OBJECTIVE: To summarize the biological characteristics of neural stem cells, and the separation, purification, differentiation and source of neural stem cells. DATA SOURCES: An online search of Pubmed database was und... OBJECTIVE: To summarize the biological characteristics of neural stem cells, and the separation, purification, differentiation and source of neural stem cells. DATA SOURCES: An online search of Pubmed database was undertaken to identify English articles about the growth of neural stem cells in vitro published from January 2000 to October 2006 by using the keywords of "neural stem cells, bone marrow mesenchymal stem cells (BMSCs), umbilical cord blood stem cells, embryonic stem cells (ESC), separation methods, neural growth factor". And relevant articles published in IEEE/IEE Electronic Library (IEL) database, Springer Link database and Kluwer Online Journals were also searched. Chinese relevant articles published between January 2000 to October 2006 were searched with the same keywords in Chinese in Chinese journal full-text database.STUDY SELECTION: The articles were primarily screened, and then the full-texts were searched. Inclusive criteria: ① Articles relevant to the biological characteristics and classification of neural stem cells; ② Articles about the source, separation and differentiation of the ESCs, BMSCs and umbilical cord blood stem cells. The repetitive studies and reviews were excluded.DATA EXTRACTION: Thirty articles were selected from 203 relevant articles according to the inclusive criteria. Articles were excluded because of repetition and reviews.DATA SYNTHESIS: Neural stem cells have the ability of self-renewing and high differentiation, and they are obtained from ESCs, nerve tissue, nerve system, BMSCs and umbilical cord blood stem cells. ESCs can be separated by means of mechanical dissociation is better than that of the trypsin digestion, BMSCs by density gradient centrifuge separation, hemolysis, whole-blood culture, etc., and umbilical cord blood stem cells by Ficoll density gradient centrifugation, hydroxyethyl starch (HES) centrifugation sedimentation, etc. Neural growth factor (NGF) and other factors play an important role in the growth of NSCs, such as transforming growth factor (TGF) is an important player in repairing organs, NGF accelerates the process of growth, insulin-like growth factor serves importantly in the differentiation of stem cells into neuron-like cells. CONCLUSION: As unipotent stem cells, NSCs have the abilities of self-renewal and potential of high differentiation. The method of mechanical dissociation is better than trypsin digestion in e separating ESCs. However, density gradient centrifuge separation is better than other methods in the separation of the BMSCs. NGF and other factors play an important role in the growth of NSCs. 展开更多
关键词 NSCS CELL STEM differentiation and biological characteristics of neural stem cells In vitro growth BMSCS
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Biological Characteristics and Culture Conditions of Hericium coralloides(Scop.)Pers.
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作者 Tong YANG Jianrui WANG Weihang PENG 《Medicinal Plant》 CAS 2020年第5期32-35,40,共5页
[Objectives]To study the biological characteristics and culture conditions of Hericium coralloides(Scop.)Pers.[Methods]The wild H.coralloides strain of Changbai Mountain was used as the experimental material to conduc... [Objectives]To study the biological characteristics and culture conditions of Hericium coralloides(Scop.)Pers.[Methods]The wild H.coralloides strain of Changbai Mountain was used as the experimental material to conduct a single factor test on its biological characteristics.[Results]The ideal available carbon source and nitrogen source are glucose and ammonium sulfate,respectively,the pH is 3.5-4.0,and the temperature is 20-22℃.Through the orthogonal experiment of 4 factors and 4 levels,it is found that the degree of influence of the 4 factors on H.coralloides is temperature>pH>nitrogen source>carbon source.[Conclusions]The optimum conditions for the mycelium culture of H.coralloides:the carbon source is glucose,and the nitrogen source is yeast extract or peptone,and pH is 3.5-4.0,and temperature is 20-22℃. 展开更多
关键词 Hericium coralloides(Scop.)Pers. biological characteristics Carbon source Nitrogen source PH TEMPERATURE
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Study on Biological Characteristics of Caged Tetrao parvirostris
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作者 Liu Hao Huang Huiwen 《Animal Husbandry and Feed Science》 CAS 2020年第5期25-28,共4页
The characteristics of digestive system,breeding habits,feather growth and molting of Tetrao parvirostris were studied,in order to provide the scientific basis for artificial breeding of T.parvirostris.
关键词 Tetrao parvirostris biological characteristics Digestive system Breeding habit FEATHER
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Morphological and Biological Characteristics of Rhynchaenus empopulifolis in Tai’an,China
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作者 Xie Na 《Plant Diseases and Pests》 CAS 2021年第1期27-30,共4页
Rhynchaenus empopulifolis is a defoliator harming poplar,and its occurrence is reported in Tai’an area for the first time.Through indoor rearing and forest investigation,the morphological,biological and damage charac... Rhynchaenus empopulifolis is a defoliator harming poplar,and its occurrence is reported in Tai’an area for the first time.Through indoor rearing and forest investigation,the morphological,biological and damage characteristics of R.empopulifolis in Tai’an were observed,and color pictures of each instar and local characteristics of adult as well as damage symptoms were provided,in order to lay a theoretical basis for rapid identification and precise control of R.empopulifolis. 展开更多
关键词 Rhynchaenus empopulifolis Morphological characteristics biological characteristics Damage status
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Biological Characteristics and Research Status of Acetic Acid Bacteria for Fruit Vinegar Brewing
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作者 Jinghong WANG 《Agricultural Biotechnology》 CAS 2019年第6期68-69,74,共3页
Fruit vinegar is a new beverage emerging in recent years because of its rich nutrition. At present, acetic acid bacteria are main strains used in the fruit vinegar production. Acetic acid bacteria are a general term f... Fruit vinegar is a new beverage emerging in recent years because of its rich nutrition. At present, acetic acid bacteria are main strains used in the fruit vinegar production. Acetic acid bacteria are a general term for a class of bacteria that can oxidize ethanol to acetic acid. This paper mainly summarized the biological characteristics and research status of acetic acid bacteria for fruit vinegar brewing, in order to provide a theoretical basis for the selection of high-quality acetic acid bacteria for fruit vinegar brewing. 展开更多
关键词 Fruit vinegar Acetic acid bacteria biological characteristics
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Culture of Human Tendon Cell Transfected by Human Telomerase Reverse Transcriptase Plasmid and their Biological CharacteristicsIn Vitro
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作者 Hui-Qi XIE~1 Zhi-Ming YANG~(1△) Fan LIN~1 Yi QU~21(Division of Stem Cell and Tissue Engineering, State Key Laboratory of Biotherapy, Sichuan University, Chengdu 610041, China) 2(Department of Biochemistry and Molecular Biology, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu 610041, China) 《生物医学工程学杂志》 EI CAS CSCD 北大核心 2005年第S1期173-174,共2页
关键词 CELL Culture of Human Tendon Cell Transfected by Human Telomerase Reverse Transcriptase Plasmid and their biological characteristicsIn Vitro
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Biological characteristics and conservation genetics of the narrowly distributed rare plant Cinnamomum chago(Lauraceae) 被引量:1
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作者 Wenjing Dong Xue Zhang +3 位作者 Yang Guansong Liu Yang Yuehua Wang Shikang Shen 《Plant Diversity》 SCIE CAS CSCD 北大核心 2016年第5期247-252,共6页
Cinnamomum chago(family Lauraceae) is an essential source of timber and oil.This plant is narrowly distributed in the western part of the Yunnan Province.In this study,the distribution,habitat,and biological character... Cinnamomum chago(family Lauraceae) is an essential source of timber and oil.This plant is narrowly distributed in the western part of the Yunnan Province.In this study,the distribution,habitat,and biological characteristics of C.chago were examined through field investigation.The genetic diversity and the variation of the remnant populations were also studied using the inter-simple sequence repeat technique.Results showed that C.chago is mainly distributed in the upstream tributary mountains of Lancang River in Yunlong County of Yunnan Province.The species distribution exhibited a fragmented pattern with five isolated populations and high-frequency anthropogenic interference.A combination of morphological features(opposite leaves,pinnate leaf veins,absence of glandular fossa,large drupe,small punch,and pollen surface with triangular spike grain,with cushion bumps at the base) indicated that C.chago is a key phylogenetic taxon between the two sections of Asian Cinnamomum plants(Sect.Camphora(Trew) Meissn.and Sect.Cinnamomum).Analysis of the genetic diversity of C.chago indicated that it has a moderately high level of genetic diversity at the population and species levels(populations level:N_e = 1.629,H = 0.348,1= 0.504,and PPB = 83.3%;species level:N_e = 1.864,H = 0.460,1 = 0.652,and PPB = 100%).Analysis of molecular variance revealed that 17%of the genetic variation was divided between the populations,whereas 83%was observed within the populations.Based on these results,we suggest the inclusion of C.chago in the Wild Plants with Extremely Small Populations in China.Moreover,the species should be given special attention and protection.Some strategies were proposed for the conservation of the C.chago populations. 展开更多
关键词 Cinnamomum chago HABITAT biological characteristic Genetic diversity Conservation strategies
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Biological characteristics of marine bacterium S-9801 strain and its culture conditions of pigment production 被引量:2
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作者 Tian Li He Peiqing +3 位作者 Wu Hongqing Wen Zhanbo Liu Chenlin Li Guangyou 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2002年第4期541-545,共5页
Strain of Flavobacterium sp.(S-9801),was screened from 207 strains of marine bacteria isolated from the Bohai Sea continental shelf and the Zhujiang Estuary,for its red pigment production.The biological characteristic... Strain of Flavobacterium sp.(S-9801),was screened from 207 strains of marine bacteria isolated from the Bohai Sea continental shelf and the Zhujiang Estuary,for its red pigment production.The biological characteristics of strain S-9801 and culture conditions of pigment production have been checked out in this study. The color of the bacterial colony on 2216E medium was from coccineus to rose bengal. Optimum culture conditions were sodium chloride concentration(g/dm3),10~30;pH,3~8;temperature,25~28℃;tryptone and yeast extract as nitrogen sources and glucose as carbon source. Under optimum conditions,pigment accumulation started after 12 h,reaching a maximum rate of synthesis at 36 h. 展开更多
关键词 MARINE bacteria PIGMENT production biological characteristics CULTURE conditions
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Construction of the tissue engineering seed cells(HaCaT-EGF) and analysis of its biological characteristics 被引量:2
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作者 Ke Tao Xiao-Zhi Bai +5 位作者 Zhan-Feng Zhang Ji-Hong Shi Xiao-Qiang Li Chao-Wu Tang Da-Hai Hu Jun-Tao Han 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2013年第11期893-896,共4页
Objective:To construct the tissue engineering seed cell(HaCaT cell line) with stable expression of the human epidermal growth factor(EGF),and analyze the changes of its biological characteristics.Methods:PCDNA3.1-EGF ... Objective:To construct the tissue engineering seed cell(HaCaT cell line) with stable expression of the human epidermal growth factor(EGF),and analyze the changes of its biological characteristics.Methods:PCDNA3.1-EGF eukaryotic expression vector was transferred into HaCaT cell,and G418 was utilized to select the HaCaT-EGF cell line.Using an inverted microscope,PCR,ELISA method to detect the changes of the cell morphology,the expression of the ECF gene and protein,and the mRNA expression levels of apoptosis related molecule Caspase-3,the cell cycle related protein cyclin D1.Results:The mRNA expression levels of the obtained HaCaT-ECF cell were more than 100 times higher than the level of ordinary HaCaT cell.The colony of the HaCaT-EGF cells was more focused and tight compared to the empty vector transfected HaCaT cells and normal HaCaT cells.The expression levels of apoptotic factor Caspase-3 and cyclin Dt in HaCaT-EGF cell were significantly higher than those in the empty vector HaCaT- pcDNA3.1 cell,and the differences were statistically significant(P<0.01),but there was no significant difference compared to the normal HaCaT cells(P>0.05).Conclusions: HaCaT-EGF cell can continuously secrete ECF,and the biological characteristic is stable.It can be used for tissue engineering experiment and is an ideal seed cell for constructing tissue engineered skin. 展开更多
关键词 TISSUE engineering HACAT Gene TRANSFECTION biological characteristics
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STUDY ON BIOLOGICAL CHARACTERISTICS OF HENDERSORNIA ACICOLA 被引量:1
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作者 何秉章 迟玉杰 +1 位作者 齐国信 杨立新 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1994年第4期37-40,共4页
The morphological and cultural characteristics of Hendersonia acicola Munch & Tub,, isolated from the needles of Pinus sylvestris var. mongolica Litvin, were described. The fungi was cultured on three kinds of med... The morphological and cultural characteristics of Hendersonia acicola Munch & Tub,, isolated from the needles of Pinus sylvestris var. mongolica Litvin, were described. The fungi was cultured on three kinds of media and the speed of mycelial growth and the required time to produce conidia were different. On the medium of needle decoction agar, the fungi grew fast and produced conidia after 5 days culturing. On PDA came second and it needed 7 days to produce conidia. On the medium of maize flour agar, it grew slowly and produces conidia after 27 days incubating. The fungi cannot produce conidia under darkness on all three kinds of media.The conidia can germinate at 8℃ -28℃. The optimum conditions for conidia to germinate are 25℃, RH 100% and pH 4 and under these conditions it only takes four hours for conidia to germinate. The conidia germination is not affected by 展开更多
关键词 Hendersonia acicola biological characteristics PINUS SYLVESTRIS VAR. MONGOLICA
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Biological Characteristics of Aeromonas Strains in Nanchang Area 被引量:1
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作者 Xinyi SHAN Dongxu WEN +5 位作者 Xiaolan LIU Wangming TAO Mengjuan ZHANG Wei QI Fengwei ZHANG Zhixiu ZHU 《Agricultural Biotechnology》 CAS 2019年第3期107-111,179,共6页
[Objectives]This study was conducted to find effective measures to prevent and control Pelteobagrus fulvidraco hemorrhage.[Methods]Typical disease materials were collected for bacterial isolation and culture and biolo... [Objectives]This study was conducted to find effective measures to prevent and control Pelteobagrus fulvidraco hemorrhage.[Methods]Typical disease materials were collected for bacterial isolation and culture and biological characteristics detection,and morphological characteristics were observed by pure culture method.Biochemical characteristics were identified by micro biochemical method.Molecular identification was performed by PCR amplification method.Drug resistance was detected by disk diffusion method.The agar diffusion method was used for the detection of in-vitro inhibitory effect.The immunogenicity of the isolates was detected by subcutaneous immunoassay.The virulence factor was detected by spot inoculation.The intraperitoneal injection was used for the detection of pathogenicity.[Results]The isolates were round,grayish white,and identified as Aeromonas.They fermented maltose,glucose,etc.,did not ferment lactose,and were negative for urea and H2S and positive for lysine and arginine.The target fragment appeared at 1 500,and the sequences shared the highest homology with Aeromonas.The isolates were highly susceptible to amikacin and gentamicin,and resistant to penicillin G and tetracycline.Eight lactic acid bacteria strains produced 1.1-1.9 cm of inhibition zone against the isolates.After the second vaccination,the titer reached 2^13;both hemolysin and protease were produced;and the test mice died within 24 h.[Conclusions]The isolates are Aeromonas,and have strong drug resistance,immunogenicity and pathogenicity.Inactivated emusion-oil vaccines of Aeromonas combined with the co-use of lactic acid bacteria and susceptible drugs can prevent the outbreak of diseases caused by Aeromonas. 展开更多
关键词 Pelteobagrus FULVIDRACO AEROMONAS biological characteristics
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Biological characteristics of entomogenous nematodes
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作者 崔景岳 王宝升 +3 位作者 苏骏 李仲秀 王庆雷 刘春芹 《华北农学报》 CSCD 北大核心 1994年第S2期54-60,共7页
Studies indicat that; 1. when soil moisture is above 15% and soil temperature is 20-28℃ ,the condition is benefic for infecting and reproducing of the nematodes. At the same time,this condition is samely needed for t... Studies indicat that; 1. when soil moisture is above 15% and soil temperature is 20-28℃ ,the condition is benefic for infecting and reproducing of the nematodes. At the same time,this condition is samely needed for the white grubs; 2. the migration ability of the nematodes is lower in soil of field than that in tested soil of the laboratory. But in general,the nematodes appplyed into soil distribute mainly in the ploughed layer and a migration area for them can be formed in the direction of horizontal; 3. observations reveal that invasion time of the S. glaseri NC34 into larval (H. parallela) through intersegmental membrane of body segment and foot after the inoculation is 30 min,and it for invading cuticle of larvae body side is 120 min. But the infection time is different in the different individuals of S. glaseri and in the different species of grubs. 展开更多
关键词 entomogenous NEMATODE GRUB .beetle biological characteristics MIGRATION ABILITY
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Study on Biological Characteristics of Livestock Eperythrozoon
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作者 Peng Haisheng Xie Minghua Mu Qionghua 《Animal Husbandry and Feed Science》 CAS 2015年第6期372-377,共6页
Based on the study of infection and morphological characteristics of 12 kinds of livestock Eperythrozoon,disinfection test by drugs in vitro,disinfection test by ultraviolet light,Eperythrozoon survival test at differ... Based on the study of infection and morphological characteristics of 12 kinds of livestock Eperythrozoon,disinfection test by drugs in vitro,disinfection test by ultraviolet light,Eperythrozoon survival test at different times and temperatures,drug sensitivity test and clinical treatment of infected swines were carried out on Eperythrozoon suis and Eperythrozoon wenyonii to further study the biological characteristics. Test results showed that infection level of livestock Eperythrozoon was high,while morbidity was low. Eperythrozoon suis and Eperythrozoon wenyonii could survive for 1 year at 3- 5 ℃,180 d at 16- 26 ℃ and 30 min at- 20 ℃,while which died instantly at 65 ℃. Eperythrozoon was sensitive to general chemical disinfection drugs,while not sensitive to ultraviolet light disinfection. Transmission of Eperythrozoon mainly included contagious transmission and vertical transmission. Results of drug sensitivity test showed that Eperythrozoon was sensitive to Tetracycline and antigen insect drugs. Sizes and shapes of different livestock Eperythrozoon were different. The study provided a scientific basis for the effective prevention and treatment of livestock Eperythrozoonosis. 展开更多
关键词 EPERYTHROZOON INFECTION rate MORPHOLOGICAL characteristics biological characteristics
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Clinical utilities and biological characteristics of melanoma sentinel lymph nodes
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作者 Dale Han Daniel C Thomas +3 位作者 Jonathan S Zager Barbara Pockaj Richard L White Stanley PL Leong 《World Journal of Clinical Oncology》 CAS 2016年第2期174-188,共15页
An estimated 73870 people will be diagnosed with melanoma in the United States in 2015,resulting in 9940 deaths.The majority of patients with cutaneous melanomas are cured with wide local excision.However,current evid... An estimated 73870 people will be diagnosed with melanoma in the United States in 2015,resulting in 9940 deaths.The majority of patients with cutaneous melanomas are cured with wide local excision.However,current evidence supports the use of sentinel lymph node biopsy(SLNB) given the 15%-20% of patients who harbor regional node metastasis.More importantly,the presence or absence of nodal micrometastases has been found to be the most important prognostic factor in earlystage melanoma,particularly in intermediate thickness melanoma.This review examines the development of SLNB for melanoma as a means to determine a patient's nodal status,the efficacy of SLNB in patients with melanoma,and the biology of melanoma metastatic to sentinel lymph nodes.Prospective randomized trials have guided the development of practice guidelines for use of SLNB for melanoma and have shown the prognostic value of SLNB.Given the rapidly advancing molecular and surgical technologies,the technical aspects of diagnosis,identification,and management of regional lymph nodes in melanoma continues to evolve and to improve.Additionally,there is ongoing research examining both the role of SLNB for specific clinical scenarios and the ways to identify patients who may benefit from completion lymphadenectomy for a positive SLN.Until further data provides sufficient evidence to alter national consensusbased guidelines,SLNB with completion lymphadenectomy remains the standard of care for clinically node-negative patients found to have a positive SLN. 展开更多
关键词 MELANOMA Metastasis Review BIOLOGIC characteristics SENTINEL LYMPH NODE SENTINEL LYMPH NODE biopsy
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Biological Characteristics of Morel and Analysis of Its Cultivation Adaptability in Tianjin
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作者 Shufang LI Xiaoming CHEN +4 位作者 Jianhua LIU Shichun YANG Jinze YU Na ZHANG Zhijun ZHANG 《Asian Agricultural Research》 2019年第2期92-93,99,共3页
Biological characteristics of morel,climatic conditions and characteristics of Tianjin,and facilities of greenhouses in Tianjin were introduced firstly,and then the cultivation adaptability of morel in Tianjin was ana... Biological characteristics of morel,climatic conditions and characteristics of Tianjin,and facilities of greenhouses in Tianjin were introduced firstly,and then the cultivation adaptability of morel in Tianjin was analyzed. This study aims to let farmers learn more about the rare edible fungus——morel and provide relevant theoretical basis and feasibility reference for the promotion and application of morel cultivation in Tianjin. 展开更多
关键词 MOREL biological characteristics CULTIVATION ADAPTABILITY
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Biological Characteristics of Fusarium oxysporum f. sp.niveum Isolated from Watermelon Cultivated in Plastic Greenhouse and Indoor Toxicity Determination of Different Fungicides in Hainan Province of China 被引量:2
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作者 Fan Hongyan Zhou Wenjing +2 位作者 Wang Xianghe Luo Zhiwen He Fan 《Plant Diseases and Pests》 CAS 2013年第5期1-5,15,共6页
[Objective]The paper was to study biological characteristics of Fusarium oxysporum f.sp.niveum in watermelon cultivated in plastic greenhouse in Hainan Province of China and to determine indoor toxicity of fungicides.... [Objective]The paper was to study biological characteristics of Fusarium oxysporum f.sp.niveum in watermelon cultivated in plastic greenhouse in Hainan Province of China and to determine indoor toxicity of fungicides.[Method]Effects of various factors on mycelial growth and spore germination were studied,and the lethal temperature of spores and indoor toxicity of fungicides were also determined.[Result]The fungal mycelium had a better growth rate on watermelon juice medium than the others.The optimum temperature for mycelial growth and spore germination were 28℃and 30℃,and the optimum pH values were7-8 and 7-9,respectively.Light-dark alternation was conducive for mycelial growth.The lethal temperature of spore was 60℃for 5 min.The fungal mycelium grew better while taking fructose and glucose as carbon sources and yeast extract and peptone as nitrogen sources.Toxicity determination showed that 50%prochloraz-manganese chloride complex WP had the greatest inhibition effect on mycelial growth,with the EC50value of 0.730 9μg/mL;followed by 32.5%benzoic azoxystrobin SC,30%benzoylate·propiconazol EC,10%difenoconazole WG,25%bromothalonil·carbendazim WP and 25%bromothalonil WP,with the EC50values from 1.884 7μg/mL to 8.161 0μg/mL.[Conclusion]The study provided basic data for field control against F.oxysporum f.sp.niveum on watermelon cultivated in plastic greenhouse in Hainan Province. 展开更多
关键词 室内毒力测定 生物学特性 塑料大棚 西瓜汁 海南省 杀菌剂 SP 多菌灵可湿性粉剂
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Physico-Chemical and Biological Characteristics of the Nklobisson Artificial Lake in Yaounde, Cameroon
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作者 Josephine Ndjama Gideon Aghaindum Ajeagah +7 位作者 Ndondo Gustave Raoul Nkoue Wirmvem Mengnjo Jude Ngon Eric Belmond Birama Gloria Eneke Takem Eyong Andrew Ako Ako Mohamadou Bello Tchouya Romaric Victorien Ntchantcho Joseph Victor Hell 《Journal of Water Resource and Protection》 2017年第12期1547-1563,共17页
The deterioration of water quality in lakes constitutes an environmental problem faced by humanity. The Nkolbisson artificial lake which is located downstream of the Abiergue and Mintotomo streams in Yaounde is under ... The deterioration of water quality in lakes constitutes an environmental problem faced by humanity. The Nkolbisson artificial lake which is located downstream of the Abiergue and Mintotomo streams in Yaounde is under the influence of various forms of pollution, mostly resulting from human activities. There is proliferation of algae on the lake surface that consumes the available oxygen in the lake. The main objective of the current study is to evaluate the different forms of pollutants in the lake, in order to propose efficient solutions for a suitable management strategy, basing on the physico-chemical and biological analysis. The lake retains an average of 2535.49 tons/year of suspended solids in the rainy season and 1438.05 tons/year in the dry season. The range of dissolved oxygen (5.2 - 3.8 mg/l);pH (7.8 - 6.8);temperature (23.9°C - 23.1°C);electrical conductivity (266.1 - 87.3 μS/cm);turbidity (22.3 - 10 UNT);suspended solid (240 - 40 mg/l);BOD (55 - 8 mg/l);COD (76 - 87.3 mg/l). Biologically, faecal coliforms fluctuates between (42 × 102 - 425 × 103 FCU/100 ml), faecal streptococci (8 × 103 - 158 × 103 FCU/100 ml) and total Coliform (15 × 103 - 78 × 106 FCU/100 ml) evidence that, the studied lake is highly polluted. Consequently the lake retains an average of 2888.7 tons/year of suspended matter. 展开更多
关键词 biological PHYSICO-CHEMICAL POLLUTION Artificial LAKE Cameroon
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Comparison of biological characteristics of marrow mesenchymal stem cells in hepatitis B patients and normal adults 被引量:9
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作者 Liang Peng Hua Li Lin Gu Xiao-Mou Peng Yang-Su Huang Zhi-Liang Gao 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第11期1743-1746,共4页
AIM: To establish a culture system of marrow mesenchymal stem cells (MSCs)from hepatitis B patients and normal adults and to compare their biological characteristics. METHODS: MSCs were isolated from bone marrow in 34... AIM: To establish a culture system of marrow mesenchymal stem cells (MSCs)from hepatitis B patients and normal adults and to compare their biological characteristics. METHODS: MSCs were isolated from bone marrow in 34 male hepatitis B patients and 15 male normal adults and cultivated in vitro. Their biological characteristics including surface markers, shapes and appearances, growth curves, first passage time and passage generations were compared. RESULTS: Cultivation achievement ratio of hepatitis B patients was lower than that of normal adults, no statistical significance (82.35% vs 100%, P > 0.05). Compared with MSCs of normal adults, MSCs of hepatitis B patients presented a statistical lower growth curve, longer first passage time (13.0 ± 1.6 d vs 11.4 ± 1.5 d, P < 0.05), fewer passaging generation numbers (10.5 ± 1.4 generations vs 12.3 ± 1.7 generations, P < 0.05), though both shared same appearances, shapes and surface markers. MSCs in hepatitis B patients would expand, spread out and age more easily and there were more refractive particles in the cytoplasm. CONCLUSION: MSCs from hepatitis B patients can be cultured in vitro. Although their appearance, shape and surface marker are similar to those of MSCs from normal adults, there are differences in their biological characteristics. 展开更多
关键词 乙型肝炎患者 正常人 骨髓间叶干细胞 生物学特性 比较研究
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Study on Biological Characteristics and Toxicity Determination of Colletotrichum orbiculare Causing Anthracnose of Watermelon in Hainan Province 被引量:1
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作者 ZHOU Wen-jing FAN Hong-yan +1 位作者 HE Fan WANG Yun-qin 《Plant Diseases and Pests》 2012年第1期5-9,共5页
[Objective] This paper was aimed to study the biological characteristics of Colletotrichum orbiculare(Berk.et Mont.) Arx, and accomplish the preliminary screening the test of fungicides. [Method]The pathogen was isola... [Objective] This paper was aimed to study the biological characteristics of Colletotrichum orbiculare(Berk.et Mont.) Arx, and accomplish the preliminary screening the test of fungicides. [Method]The pathogen was isolated from the infected leaves of watermelon collected from greenhouse in Hainan Province. The biological characteristics of C. orbiculare and indoor toxicity of fungicides were studied. [Results] The mycelium grew fastest on the medium with leaf extract of watermelon. The optimum temperature for mycelial growth and spore germination was 28 and 30 ℃, and the optimum pH was 7-9 and 6-8, respectively. The continuous darkness condition was most suitable for mycelial growth. The lethal temperature of spore was 55 ℃ water bath for 10 min in water bath. The suitable carbon sources were maltose, L-arabinose and glucose, and the suitable nitrogen sources were yeast extract, beef extract and peptone. In the indoor toxicity determination, 32.5% Benzoic azoxystrobin SC, 50% Dichlorotetrakis WP and 10% Difenoconazole WG showed better inhibition effects against the mycelial growth of C. orbiculare, with the EC50 values of 0.018 0, 0.060 2 and 0.471 5 μg/ml, respectively. [Conclusion]The research provided theoretical basis for the control of watermelon anthracnose in watermelon fields. 展开更多
关键词 植物病虫害 预防 植物保护 植物检疫
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