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Efficient and Soluble Expression of α Protein of Clostridium perfringens and Preparation of Genetic Engineering Subunit Vaccine
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作者 Sun Yu Yang Lin +6 位作者 Wang Chuanbin Dong Hao Qu Ping Zhao Bolin Hu Dongmei Yang Tianyi Song Xiaohui 《Animal Husbandry and Feed Science》 CAS 2017年第5期284-288,305,共6页
[Objective] The paper was to develop genetic engineering vaccine that can express α exotoxin antigen protein efficiently without destroying its immunogenicity for preventing and controlling the diseases caused by Clo... [Objective] The paper was to develop genetic engineering vaccine that can express α exotoxin antigen protein efficiently without destroying its immunogenicity for preventing and controlling the diseases caused by Clostridium perfringens. [Method] Efficiently expressed soluble recombinant α protein was obtained from Escherichia coli expression system by optimizing codon,removing signal peptide,selecting sequences with better hydrophilicity and antigenicity,and optimizing expression conditions. [Result] Mice obtained higher serum antibody level when immunized by α protein,and the immune protection rates against type A,type B,type C and type D C. perfringens were 100%,90%,85% and 90%,respectively. The antibody titer of mice within 7-14 d after the third immunization reached the peak. [Conclusion]The α protein has good immunogenicity,and can be further used to develop genetic engineering subunit vaccines for preventing C. perfringens. 展开更多
关键词 CLOSTRIDIUM perfringens α PROTEIN SOLUBLE expression and PURIFICATION genetic engineering SUBUNIT VACCINE
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Advances in homology directed genetic engineering of human pluripotent and adult stem cells
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作者 Kalpith Ramamoorthi Donald Curtis Prashanth Asuri 《World Journal of Stem Cells》 SCIE CAS 2013年第4期98-105,共8页
The ability to introduce precise genomic modifications in human cells has profound implications for both basic and applied research in stem cells, ranging from identification of genes regulating stem cell self-renewal... The ability to introduce precise genomic modifications in human cells has profound implications for both basic and applied research in stem cells, ranging from identification of genes regulating stem cell self-renewal and multilineage differentiation to therapeutic gene correction and creation of in vitro models of human diseases. However, the overall efficiency of this process is challenged by several factors including inefficient gene delivery into stem cells and low rates of homology directed site-specific targeting. Recent studies report the development of novel techniques to improve gene targeting efficiencies in human stem cells; these methods include molecular engineering of viral vectors to efficiently deliver episomal genetic sequences that can participate in homology directed targeting, as well as the design of synthetic proteins that can introduce double-stranded breaks in DNA to initiate such recombination events. This review focuses on the potential of these new technologies to precisely alter the human stem cell genome and also highlights the possibilities offered by the combination of these complementary strategies. 展开更多
关键词 HUMAN stem cells genetic engineering Engineered viruses Synthetic RESTRICTION ENDONUCLEASES
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Eradication of malaria through genetic engineering:the current situation 被引量:1
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作者 Wing-Chui Chong Rusliza Basir Yam Mun Fei 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2013年第2期85-94,共10页
Malaria is an intra-cellular parasitic protozoon responsible for millions of deaths annually.Host and parasite genetic factors are crucial in affecting susceptibility to malaria and progression of the disease.Recent i... Malaria is an intra-cellular parasitic protozoon responsible for millions of deaths annually.Host and parasite genetic factors are crucial in affecting susceptibility to malaria and progression of the disease.Recent increased deployment of vector controls and new artemisinin combination therapies have dramatically reduced the mortality and morbidity of malaria worldwide.However, the gradual emergence of parasite and mosquito resistance has raised alarm regarding the effectiveness of current artemisinin-based therapies.In this review,mechanisms of anti-malarial drug resistance in the Plasmodium parasite and new genetically engineered tools of research priorities are discussed.The complexity of the parasite lifecycle demands novel interventions to achieve global eradication.However,turning laboratory discovered transgenic interventions into functional products entails multiple experimental phases in addition to ethical and safety hurdles.Uncertainty over the regulatory status and public acceptance further discourage the implementation of genetically modified organisms. 展开更多
关键词 MALARIA VECTOR control Resistance PLASMODIUM PARASITE genetically engineered TOOLS
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Advances in Cold Tolerance Genes and Their Application in Genetic Engineering of Plant for Cold Tolerance
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作者 段俊枝 李莹 +3 位作者 周雷 潘英华 赵明忠 任银玲 《Agricultural Science & Technology》 CAS 2015年第11期2421-2427,2432,共8页
Low temperature is one of the main environmental stress factors influenc- ing plant growth and development and crop yield. Cold tolerance genes and progress of their application in genetic engineering of plant for col... Low temperature is one of the main environmental stress factors influenc- ing plant growth and development and crop yield. Cold tolerance genes and progress of their application in genetic engineering of plant for cold tolerance were reviewed comprehensively and systematically from the aspect of genes that are in- volved in biosynthesis of osmotic substances, genes coding fatty acid desaturation enzymes, antifreeze protein genes, genes coding antioxidant enzymes and so on, aiming at laying the foundation for genetic improvement of cold tolerance and breeding of plants. 展开更多
关键词 PLANT Cold tolerance Functional genes genetic engineering New progress
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The “3 Genomic Numbers” Discovery: How Our Genome Single-Stranded DNA Sequence Is “Self-Designed” as a Numerical Whole
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作者 Jean-Claude Perez 《Applied Mathematics》 2013年第10期37-53,共17页
This article proves the existence of a hyper-precise global numerical meta-architecture unifying, structuring, binding and controlling the billion triplet codons constituting the sequence of single-stranded DNA of the... This article proves the existence of a hyper-precise global numerical meta-architecture unifying, structuring, binding and controlling the billion triplet codons constituting the sequence of single-stranded DNA of the entire human genome. Beyond the evolution and erratic mutations like transposons within the genome, it’s as if the memory of a fossil genome with multiple symmetries persists. This recalls the “intermingling” of information characterizing the fractal universe of chaos theory. The result leads to a balanced and perfect tuning between the masses of the two strands of the huge DNA molecule that constitute our genome. We show here how codon populations forming the single-stranded DNA sequences can constitute a critical approach to the understanding of junk DNA function. Then, we suggest revisiting certain methods published in our 2009 book “Codex Biogenesis”. In fact, we demonstrate here how the universal genetic code table is a powerful analytical filter to characterize single-stranded DNA sequences constituting chromosomes and genomes. We can then show that any genomic DNA sequence is featured by three numbers, which characterize it and its 64 codon populations with correlations greater than 99%. The number “1” is common to all sequences, expressing the second law of Chargaff. The other 2 numbers are related to each specific DNA sequence case characterizing life species. For example, the entire human genome is characterized by three remarkable numbers 1, 2, and Phi = 1.618 the golden ratio. Associated with each of these three numbers, we can match three axes of symmetry, then “imagine” a kind of hyperspace formed by these codon populations. Then we revisit the value (3-Phi)/2 which is probably universal and common to both the scale of quarks and atomic levels, balancing and tuning the whole human genome codon population. Finally, we demonstrate a new kind of duality between “form and substance” overlapping the whole human genome: we will show that—simultaneously with the duality between genes and junk DNA—there is a second layer of embedded hidden structure overlapping all the DNA of the whole human genome, dividing it into a second type of duality information/redundancy involving golden ratio proportions. 展开更多
关键词 genetic Code CODON Populations Junk DNA Cancer Genomics Chromosomal Translocations Genomes Diversity Chromosomes Diversity WHOLE Human GENOME DNA SEQUENCE Phi the Golden Ratio Fibonacci NUMBERS Information Theory SYMMETRY Cellular Automata Chargaffs CODON Level SYMMETRY Principle Fractal Self-Similarity e Eulers Number Pi form and Substance Redundancy Encryption
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Interactions of chemical carcinogens and genetic variation in hepatocellular carcinoma 被引量:1
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作者 Yu-Jing Zhang 《World Journal of Hepatology》 CAS 2010年第3期94-102,共9页
In the etiology of hepatocellular carcinoma (HCC), in addition to hepatitis B virus and hepatitis C virus infections, chemical carcinogens also play important roles. For example, aflatoxin B 1 (AFB 1 ) epoxide reacts ... In the etiology of hepatocellular carcinoma (HCC), in addition to hepatitis B virus and hepatitis C virus infections, chemical carcinogens also play important roles. For example, aflatoxin B 1 (AFB 1 ) epoxide reacts with guanine in DNA and can lead to genetic changes. In HCC, the tumor suppressor gene p53 codon 249 mutation is associated with AFB 1 exposure and mutations in the K -ras oncogene are related to vinyl chloride exposure. Numerous genetic alterations accumulate during the process of hepatocarcinogenesis. Chemical carcinogen DNA-adduct formation is the basis for these genetic changes and also a molecular marker which reflects exposure level and biological effects. Metabolism of chemical carcinogens, including their activation and detoxification, also plays a key role in chemical hepatocarcinogenesis. Cytochrome p450 enzymes, N -acetyltransferases and glutathione S -transferases are involved in activating and detoxifying chemical carcinogens. These enzymes are polymorphic and genetic variation influences biological response to chemical carcinogens. This genetic variation has been postulated to influence the variability in risk for HCC observed both within and across populations. Ongoing studies seek to fully understand the mechanisms by which genetic variation in response to chemical carcinogens impacts on HCC risk. 展开更多
关键词 Hepatocellular carcinoma Chemical CARCINOGENS AFLATOXIN B 1 POLYCYCLIC aromatic hydrocarbons 4-aminobiphenyl HEPATITIS B VIRUS HEPATITIS C VIRUS Glutathione S -transferase Cytochrome p450 enzymes genetic variation
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Chloroplast Genetic Engineering in Higher Plants 被引量:1
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作者 张景昱 张嫄 宋艳茹 《Acta Botanica Sinica》 CSCD 2003年第5期509-516,共8页
Chloroplast genetic engineering, with several advantages over nuclear genetic engineering, is now regarded as an attractive new technology in basic and applied research, including deepening our understanding of plasti... Chloroplast genetic engineering, with several advantages over nuclear genetic engineering, is now regarded as an attractive new technology in basic and applied research, including deepening our understanding of plastid genome, engineering plant metabolic system, generating transplastomic plants with higher resistance to insect, disease, drought and herbicide and bioproducing of antibodies and vaccines. In this review, the principle and operating system for chloroplast genetic engineering and its application in higher plants have been discussed. 展开更多
关键词 chloroplast genetic engineering transplastomic plants plastid genome
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Advantages and Disadvantages of Transgenic Animal Technology with Genetic Engineering
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作者 Mine Dosay-Akbulut 《Journal of Agricultural Science and Technology(A)》 2014年第2期177-187,共11页
Transgenic animal technology has been one of the fastest growing biotechnology areas. The exogenous genes have been introduced into the animal genome by genetic engineering, so that these genes can be inherited and ex... Transgenic animal technology has been one of the fastest growing biotechnology areas. The exogenous genes have been introduced into the animal genome by genetic engineering, so that these genes can be inherited and expressed by offspring to produce desired traits or evaluate function in elite livestock breeds. There are several methodologies for the production of transgenic animals, i.e., (1) microinjection of genes into pronuclei of fertilized ova; (2) DNA transfer by retroviruses; (3) injection of embryonic germ (EG)/embryonic stem (ES) cells previously treated with foreign DNA; (4) DNA transfer into cells and embryos with using liposomes; (5) exogenous DNA transfer while in vitro fertilization by using sperm; (6) electroporation of DNA into sperm, embryos or ova; (7) biolistics; (8) nuclear transfer (NT) with somatic cells, EG or ES cells; (9) germ line stem cell-mediated; (10) gene targeting; (! 1) gene silencing technology with RNA interference; (12) induced pluripotent stem cell; (13) zinc-finger nuclease gene targeting technology. Gene farming is one of the newest and most promising areas in modern biotechnology. Cattle, goats, sheep, pigs and rabbits are the main farm livestock species and fish is also used in transgenic technology. The question of "why make transgenic animals?" is very important. Some of the answers to this question are: (1) to obtain new knowledge; (2) to solve the genetic code; (3) to create genetic disease models; (4) to study the genetic control of physiological systems; (5) to improve animal production traits; (6) to produce new animal products. Transgenic technology is one of the main and important tools in the finding solutions to problems of growing population with their applications to different organisms, and takes more attention and interest every day. Transgenic technology creates opportunities and areas to play with organisms to fulfill the demands of people. Because of this, this paper based on mainly transgenic applications to take people's attention and exhibit its importance. 展开更多
关键词 BIOTECHNOLOGY bioreactors LIVESTOCK TRANSGENIC ANIMAL genetic engineering
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Construction and Identification of HSP70 Antisense RNA Expression Vector for Genetic Engineering Male Sterility in Plant 被引量:2
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作者 刘立科 刘根齐 +5 位作者 侯宁 刘春光 陈建南 张文会 樊颖伦 吴冰洁 《Agricultural Science & Technology》 CAS 2008年第2期81-84,128,共5页
[ Objective] In order to study the relation between the HSPTO gene and male sterility of plant further. [ Methods ] Anther specific expression promoter Osg6B of rice was coloned by PCR then connected with HSP70 antise... [ Objective] In order to study the relation between the HSPTO gene and male sterility of plant further. [ Methods ] Anther specific expression promoter Osg6B of rice was coloned by PCR then connected with HSP70 antisense fragment to construct HSPTO antisense expression vector. The expression vector was identified by PCR experiment and enzyme digestion. [ Result] The sequence of coloned Osg6B promoter had 97% homology to the published sequence, and the cis-regulatory element in promoter area was integrated. HSP70 antisense expression vector driven by the promoter Osg6B was confired by colony PCR and enzyme digestion. [ Conclusion] The construction of expression vector would lay solid foundation for utilization of genetic engineering male sterility of plant. 展开更多
关键词 HSP70 Osg6B promoter Gene engineering Male sterility
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Benefits of Genetic Engineering to the Environment and Human Health
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作者 覃靓 《海外英语》 2011年第4X期264-265,共2页
The purpose of this essay is to argue that the genetic engineering may bring about benefits to human health and the environment.By means of research of secondary source collection,relevant evidence is selected,evaluat... The purpose of this essay is to argue that the genetic engineering may bring about benefits to human health and the environment.By means of research of secondary source collection,relevant evidence is selected,evaluated and organized into three main parts:improving agricultural environment,providing effective medical therapy and supplying safe and nutrition food to human body.In order to explain the benefits that created by genetic engineering technologies,examples based on opinions of experts and results of experts' experiments are used.The research results strongly suggest that the genetic engineering has positive effects on environment and mankind.Base on those finds,the argument is justified that genetic engineering is certainly beneficial to the environment and human health.In the future,more attention and researches should be focus on the genetic engineering with the purpose of benefiting human beings and the natural worlds. 展开更多
关键词 genetic engineering BENEFITS human HEALTH environment
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基于遗传算法和最小二乘支持向量机的织物剪切性能预测 被引量:2
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作者 卢桂馥 王勇 +1 位作者 窦易文 Gui-fu Yi-wen 《计量学报》 CSCD 北大核心 2009年第6期-,共4页
提出了一种基于最小二乘支持向量机的织物剪切性能预测模型,并且采用遗传算法进行最小二乘支持向量机的参数优化,将获得的样本进行归一化处理后,将其输入预测模型以得到预测结果.仿真结果表明,基于最小二乘支持向量机的预测模型比BP神... 提出了一种基于最小二乘支持向量机的织物剪切性能预测模型,并且采用遗传算法进行最小二乘支持向量机的参数优化,将获得的样本进行归一化处理后,将其输入预测模型以得到预测结果.仿真结果表明,基于最小二乘支持向量机的预测模型比BP神经网络和线性回归方法具有更高的精度和范化能力. Abstract: A new method is proposed to predict the fabric shearing property with least square support vector machines ( LS-SVM ). The genetic algorithm is investigated to select the parameters of LS-SVM models as a means of improving the LS- SVM prediction. After normalizing the sampling data, the sampling data are inputted into the model to gain the prediction result. The simulation results show the prediction model gives better forecasting accuracy and generalization ability than BP neural network and linear regression method. 展开更多
关键词 SUPPORT VECTOR MACHINES sampling data SUPPORT VECTOR MACHINES generalization ability simulation results linear regression genetic algorithm BP neural network prediction model 线 LS-SVM least square new method
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Crop Resources Ethic in Plant Genetic Engineering and Fortune Transfer Between Generations 被引量:1
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作者 WANG Xiaowei DING Guangzhou LIANG Xueqing 《Journal of Northeast Agricultural University(English Edition)》 CAS 2006年第2期169-173,共5页
The relation between human and crop resources belongs to the ethic of resources exploitation. The purposes of discussing the ethic of crop resources are to protect the ecology and safety of crops, to gain sustainable ... The relation between human and crop resources belongs to the ethic of resources exploitation. The purposes of discussing the ethic of crop resources are to protect the ecology and safety of crops, to gain sustainable development, furthermore, to choose and form the production structure that is favorable to saving crop resources and protecting the ecology of crops. Plant genetic engineering is the technology of molecule breeding of rearrangement of inheritance materials at the level of molecule directionally, of improving plant properties and of breeding high quality and yield varieties of crops. The prominent effects of the technology on the crop ecological system are human subjective factors increasing as well as violating the nature and intensifying the conflict between human being and nature. Therefore, in plant genetic engineering, crop resources exploitation should follow certain ethic principles. Under the theory of ethics of natural resources, by the means of biologinal-statistics, the author systematically analyzed the possible model of crop resources transfer between generations as well as the transfer mode of magnitude of real materials and magnitude of value. 展开更多
关键词 plant genetic engineering crop resources ETHIC fortune transfer between generations
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Bio-Piracy on the High Seas? Benefit Sharing from Marine Genetic Resource Exploitation in Areas beyond National Jurisdiction
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作者 John Samuel Bird 《Natural Resources》 2018年第12期413-428,共16页
Transnational benefit sharing from the exploitation of Marine Genetic Resources’ (MGR’s) in Areas Beyond National Jurisdiction (ABNJ) presents a unique problem in international law. Proposals to govern MGR’s in ABN... Transnational benefit sharing from the exploitation of Marine Genetic Resources’ (MGR’s) in Areas Beyond National Jurisdiction (ABNJ) presents a unique problem in international law. Proposals to govern MGR’s in ABNJ include leaving them unregulated, governance under the International Seabed Authority (ISA) or the Convention on Biological Diversity (CBD) or implementing a new international regime. This paper demonstrates that a hybrid solution for MGR governance?under the ISA which is modeled on the CBD and The Nagoya Protocol (Nagoya), provides the most adroit solution to the problem of equal benefit and access to MGR’s for all States. This solution ensures adequate conservation of MGR’s, meanwhile fostering sustainable exploitation and maintaining equality in access, biodiversity and the sharing of financial and technological benefits amongst the internationalcommunity. Further, examining benefit sharing from bioprospecting under the CBD and Nagoya provides a foundation for a benefit-sharing regime in ABNJ under The United Nations Convention on the Law of the Sea (UNCLOS). Examining the CBD, Nagoya and UNCLOS demonstrates how benefits arising from exploitation of MGR’s in the high seas and deep bed should be included as a mandate of the ISA. This methodology is accomplished by focusing on bioprospecting for MGR’s and how the CBD and Nagoya facilitate access to the resource while ensuring that the host State or community benefits from granting access. As the CBD and Nagoya focus on benefit sharing in light of national sovereignty, and UNCLOS regulates in areas beyond national jurisdiction, the ISA is perfectly placed to adopt the principles of the CBD and Nagoya and provide a mechanism to ensure that MGR’s in ABNJ are adequately conserved and the benefits arising from their exploitation equitably shared. 展开更多
关键词 Marine genetic RESOURCES Natural RESOURCES BIODIVERSITY BIOPROSPECTING International SEABED Authority Nagoya Protocol CONVENTION on BIODIVERSITY Law Conservation Benefit Sharing High SEAS Deepsea Bed Area
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Fungi as chemical industries and genetic engineering for the production of biologically active secondary metabolites 被引量:7
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作者 Abid Ali Khan Nafees Bacha +3 位作者 Bashir Ahmad Ghosia Lutfullah Umar Farooq Russell John Cox 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2014年第11期859-870,共12页
Fungi is somewhere in between the micro and macro organisms which is a good source of producing biologically active secondary metabolites.Fungi have been used as tool for producing different types of secondary metabol... Fungi is somewhere in between the micro and macro organisms which is a good source of producing biologically active secondary metabolites.Fungi have been used as tool for producing different types of secondary metabolites by providing different nutrients at different laboratory conditions.The fungi have been engineered for the desired secondary metabolites by using different laboratory techniques,for example,homologous and heterologous expressions.This review reported how the fungi are used as chemical industry for the production of secondary metabolites and how they are engineered in laboratory for the production of desirable metabolites:also the biosynthetic pathways of the bio-organic-molecules were reported. 展开更多
关键词 FUNGI Natural products MICROBIOLOGY Molecular genetics Chemical biology
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A Review on Creating Male Sterility in Vegetable Crops by Genetic Engineering 被引量:1
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作者 C. Q. Yang Y. G. Oin +3 位作者 J. J. Lei L. Zhai B. H. Cao G. J, Chen 《Journal of Agricultural Science and Technology(B)》 2011年第8期1097-1102,共6页
With the deep researches on male sterility genetic engineering of plants, several strategies creating male sterile materials have been developed, such as causing pollen abortion by cytotoxic genes, antisense RNA or RN... With the deep researches on male sterility genetic engineering of plants, several strategies creating male sterile materials have been developed, such as causing pollen abortion by cytotoxic genes, antisense RNA or RNAi silencing the expression of genes related to pollen development, early degradation of tapetum callose leading to male sterility. Male sterile transgenic plants can be obtained through genetic transformation with related genes destroying or interfering with pollen or anther development. Male sterile cauliflower, tomato, cabbage, etc. have been developed in this way, and some begin to be used to produce hybrid seed. Appling some techniques can also maintain and restore the male sterility. These related researches will effectively promote the heterosis utilization and the development of crop breeding. This paper mainly presents their principles and applications in vegetable crops. 展开更多
关键词 VEGETABLE genetic engineering male sterility BREEDING review.
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Genetic Engineering of Field, Industrial and Pharmaceutical Crops
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作者 Hari P. Singh Bharat P. Singh 《American Journal of Plant Sciences》 2014年第26期3974-3993,共20页
Ability to modify plants at the genomic level by advanced molecular technology has enhanced the scope of improvements in plant traits attempted earlier through conventional breeding methods. Techniques such as genetic... Ability to modify plants at the genomic level by advanced molecular technology has enhanced the scope of improvements in plant traits attempted earlier through conventional breeding methods. Techniques such as genetic transformation have opened new vistas whereby functional genes, not commonly present in a particular species can be added from other species. The traits incorporated into the genetically engineered plants in the beginning were confined to those governed by dominant genes, e.g. insecticide resistance and herbicide tolerance but advancements with time now also permit the transfer of complexly inherited traits such as drought and cold tolerance. Transgenic technology is also useful in understanding gene expression and metabolic pathways which can then be used to harness the full genomic potential of the plant. This review presents a narrative on development of transgenics and their use for the improvement of field, industrial and pharmaceuticals crops. In addition, discussions are made on current status on genetically modified crops, hurdles to genetic engineering, overcoming strategies and future scope. 展开更多
关键词 genetic engineering (GE) TRANSGENIC genetically Modified (GM) FIELD CROPS INDUSTRIAL CROPS PHARMACEUTICAL CROPS Molecular FARMING
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GSTM1,GSTT1,GSTP1 and CYP1A1 genetic polymorphisms and susceptibility to esophageal cancer in a French population:Different pattern of squamous cell carcinoma and adenocarcinoma 被引量:7
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作者 Ahmed Abbas Karine Delvinquière +4 位作者 Mathilde Lechevrel Pierre Lebailly Pascal Gauduchon Guy Launoy Fran ois Sichel 《World Journal of Gastroenterology》 SCIE CAS CSCD 2004年第23期3389-3393,共5页
AIM:To evaluate the association between CYP1A1 and GSTs genetic polymorphisms and susceptibility to esophageal squamous cell carcinoma(SCC)and esophageal adenocarcinoma(ADC)in a high risk area of northwest of France. ... AIM:To evaluate the association between CYP1A1 and GSTs genetic polymorphisms and susceptibility to esophageal squamous cell carcinoma(SCC)and esophageal adenocarcinoma(ADC)in a high risk area of northwest of France. METHODS:A case-control study was conducted to investigate the genetic polymorphisms of these enzymes (CYPIAI*2C and GSTP1 exon 7 Val alleles,GSTMI*2/*2 and GSTTl *2/*2 null genotypes).A total of 79 esophageal cancer cases and 130 controls were recruited. RESULTS:GSTMI*2/*2 and CYPIAI*IA/*2C genotype frequencies were higher among squamous cell carcinomas at a level dose to statistical significance(OR =1.83,95% CI 0.88-3.83,P=0.11;OR=3.03,95% CI 0.93-9.90,P=0.07, respectively).For GSTP1 polymorphism,no difference was found between controls and cases,whatever their histological status.Lower frequency of GSTT1 deletion was observed in ADC group compared to controls with a statistically significant difference(OR=13.31,95% CI 1.66-106.92,P<0.01). CONCLUSION:In SCC,our results are consistent with the strong association of this kind of tumour with tobacco exposure.In ADC,our results suggest 3 distinct hypotheses: (1)activation of exogenous procarcinogens,such as small halogenated compounds by GSTT1;(2)contribution of GSTT1 to the inflammatory response of esophageal mucosa,which is known to be a strong risk factor for ADC, possibly through leukotriene synthesis;(3)higher sensitivity to the inflammatory process associated with intracellular depletion of glutathione. 展开更多
关键词 ACYLTRANSFERASES ADENOCARCINOMA Adult Aged Aged 80 and over Carcinoma Squamous Cell Case-Control Studies Cytochrome P-450 CYP1A1 Esophageal Neoplasms Female France genetic Predisposition to Disease Genotype Glutathione Transferase Humans Male Middle Aged Polymorphism genetic Research Support Non-U.S. Gov't Risk Factors
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Osmoregulation Mechanism of Drought Stress and Genetic Engineering Strategies for Improving Drought Resistance in Plants
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作者 DuJinyou ChenXiaoyang LiWei GaoQiong 《Forestry Studies in China》 CAS 2004年第2期56-62,共7页
Drought, one of the main adverse environmental factors, obviously affected plant growth and development. Many adaptive strategies have been developed in plants for coping with drought or water stress, among which osmo... Drought, one of the main adverse environmental factors, obviously affected plant growth and development. Many adaptive strategies have been developed in plants for coping with drought or water stress, among which osmoregulation is one of the important factors of plant drought tolerance. Many substances play important roles in plant osmoregulation for drought resistance, including proline, glycine betaine, Lea proteins and soluble sugars such as levan, trehalose, sucrose, etc. The osmoregulation mechanism and the genetic engineering of plant drought-tolerance are reviewed in this paper. 展开更多
关键词 plant drought tolerance osmoregulation mechanism trees genetic engineering
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Recent advances in the molecular genetics of resin biosynthesis and genetic engineering strategies to improve defenses in conifers
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作者 唐巍 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第2期171-179,共9页
Since the first terpenoid synthase cDNA was obtained by the reverse genetic approach from grand fir, great progress in the molecular genetics of terpenoid formation has been made with angiosperms and genes encoding a ... Since the first terpenoid synthase cDNA was obtained by the reverse genetic approach from grand fir, great progress in the molecular genetics of terpenoid formation has been made with angiosperms and genes encoding a monoterpene synthase, a sesquiterpene synthase, and a diterpene synthase. Tree killing bark beetles and their vectored fungal pathogens are the most destructive agents of conifer forests worldwide. Conifers defend against attack by the constitutive and inducible production of oleoresin that accumulates at the wound site to kill invaders and both flush and seal the injury. Although toxic to the bark beetle and fungal pathogen, oleoresin also plays a central role in the chemical ecology of these boring insects. Recent advances in the molecular genetics of terpenoid biosynthesis provide evidence for the evolutionary origins of oleoresin and permit consideration of genetic engineering strategies to improve conifer defenses as a component of modern forest biotechnology. This review described enzymes of resin biosynthesis, structural feathers of genes genomic intron and exon organization, pathway organization and evolution, resin production and accumulation, interactions between conifer and bark beetle, and engineering strategies to improve conifer defenses. 展开更多
关键词 genetic engineering strategies Resin biosynthesis Bark beetles GENOMICS Molecular genetics
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Preparation of Conotoxin MrVIB by Genetic Engineering Technology
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作者 Weiwei GUAN Jie HOU +3 位作者 Xia ZHONG Na WEI Junqing ZHANG Bingmiao GAO 《Agricultural Biotechnology》 CAS 2017年第4期28-31,37,共5页
[ Objective] The disulfide-rich conotoxin MrV1B was produced by simple and fast genetic engineering method, to find new efficient ways for the synthesis of natural active conotoxins. [Method] Primers of conotoxin gene... [ Objective] The disulfide-rich conotoxin MrV1B was produced by simple and fast genetic engineering method, to find new efficient ways for the synthesis of natural active conotoxins. [Method] Primers of conotoxin gene MrVIB were synthesized to construct expression vectors pET22b( + )/His-Xa-MrVIB and pET32a/Trx-EK-MrV1B, which were transformed into BL21 (DE3)pLysS and expressed under induction by IPTG. Recombinant proteins were purified by affinity chromatography using Ni-NTA agarose column, and the expression of the recombinant proteins was analyzed by Tricine-SDS-PAGE electrophoresis. [ Result] The recombinant conotoxins His-Xa-MrVIB and Trx-EK-MrVIB were effectively expressed in E. coli, and purified by one-step affinity chromatography, and the purity of the recombinant conotoxins was greater than 90%. [ Conclusion] The conotoxin MrVIB was effectively secreted and expressed by genetic engineering method, which could solve the problems in chemical synthesis of conotoxins including low yield, high cost and difficult purification. 展开更多
关键词 CONOTOXINS Escherichia coli genetic engineering Recombinant Expression Separation and Purification
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