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Intrahepatic portal venous systems in adult patients with cavernous transformation of portal vein: Imaging features and a new classification 被引量:1
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作者 Xin Huang Qian Lu +5 位作者 Yue-Wei Zhang Lin Zhang Zhi-Zhong Ren Xiao-Wei Yang Ying Liu Rui Tang 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2024年第5期481-486,共6页
Background: Cavernous transformation of the portal vein(CTPV) due to portal vein obstruction is a rare vascular anomaly defined as the formation of multiple collateral vessels in the hepatic hilum. This study aimed to... Background: Cavernous transformation of the portal vein(CTPV) due to portal vein obstruction is a rare vascular anomaly defined as the formation of multiple collateral vessels in the hepatic hilum. This study aimed to investigate the imaging features of intrahepatic portal vein in adult patients with CTPV and establish the relationship between the manifestations of intrahepatic portal vein and the progression of CTPV. Methods: We retrospectively analyzed 14 CTPV patients in Beijing Tsinghua Changgung Hospital. All patients underwent both direct portal venography(DPV) and computed tomography angiography(CTA) to reveal the manifestations of the portal venous system. The vessels measured included the left portal vein(LPV), right portal vein(RPV), main portal vein(MPV) and the portal vein bifurcation(PVB). Results: Nine males and 5 females, with a median age of 40.5 years, were included in the study. No significant difference was found in the diameters of the LPV or RPV measured by DPV and CTA. The visualization in terms of LPV, RPV and PVB measured by DPV was higher than that by CTA. There was a significant association between LPV/RPV and PVB/MPV in term of visibility revealed with DPV( P = 0.01), while this association was not observed with CTA. According to the imaging features of the portal vein measured by DPV, CTPV was classified into three categories to facilitate the diagnosis and treatment. Conclusions: DPV was more accurate than CTA for revealing the course of the intrahepatic portal vein in patients with CTPV. The classification of CTPV, that originated from the imaging features of the portal vein revealed by DPV, may provide a new perspective for the diagnosis and treatment of CTPV. 展开更多
关键词 Cavernous transformation of the portal vein CLASSIFICATION Direct portal venography Intrahepatic portal venous system
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Establishment of a transformation system in close relatives of wheat under the assistance of TaWOX5
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作者 Yanan Chang Junxian Liu +7 位作者 Chang Liu Huiyun Liu Huali Tang Yuliang Qiu Zhishan Lin Ke Wang Yueming Yan Xingguo Ye 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第6期1839-1849,共11页
Species closely related to wheat are important genetic resources for agricultural production,functional genomics studies and wheat improvement.In this study,a wheat gene related to regeneration,TaWOX5,was applied to e... Species closely related to wheat are important genetic resources for agricultural production,functional genomics studies and wheat improvement.In this study,a wheat gene related to regeneration,TaWOX5,was applied to establish the Agrobacterium-mediated transformation systems of Triticum monococcum,hexaploid triticale,and rye(Secale cereale L.)using their immature embryos.Transgenic plants were efficiently generated.During the transformation process,the Agrobacterium infection efficiency was assessed by histochemical staining forβ-glucuronidase(GUS).Finally,the transgenic nature of regenerated plants was verified by polymerase chain reaction(PCR)-based genotyping for the presence of the GUS and bialaphos resistance(bar)genes,histochemical staining for GUS protein,and the QuickStix strip assay for bar protein.The transformation efficiency of T.monococcum genotype PI428182 was 94.4%;the efficiencies of four hexaploid triticale genotypes Lin456,ZS3297,ZS1257,and ZS3224 were 52.1,41.2,19.4,and 16.0%,respectively;and the transformation efficiency of rye cultivar Lanzhou Heimai was 7.8%.Fluorescence in situ hybridization(FISH)and genomic in situ hybridization(GISH)analyses indicated that the GUS transgenes were integrated into the distal or near centromere(proximal)regions of the chromosomes in transgenic T.monococcum and hexaploid triticale plants.In the transgenic hexaploid triticale plants,the foreign DNA fragment was randomly integrated into the AABB and RR genomes.Furthermore,the transgene was almost stably inherited in the next generation by Mendel’s law.The findings in this study will promote the genetic improvement of the three plant species for grain or forage production and the improvement of cereal species including wheat for functional genomics studies. 展开更多
关键词 Triticum monococcum hexaploid triticale RYE TaWOX5 AGROBACTERIUM transformation efficiency
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Description of martensitic transformation kinetics in Fe-C-X(X = Ni,Cr,Mn,Si) system by a modified model
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作者 Xiyuan Geng Hongcan Chen +3 位作者 Jingjing Wang Yu Zhang Qun Luo Qian Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期1026-1036,共11页
Controlling the content of athermal martensite and retained austenite is important to improving the mechanical properties of high-strength steels,but a mechanism for the accurate description of martensitic transformat... Controlling the content of athermal martensite and retained austenite is important to improving the mechanical properties of high-strength steels,but a mechanism for the accurate description of martensitic transformation during the cooling process must be addressed.At present,frequently used semi-empirical kinetics models suffer from huge errors at the beginning of transformation,and most of them fail to exhibit the sigmoidal shape characteristic of transformation curves.To describe the martensitic transformation process accurately,based on the Magee model,we introduced the changes in the nucleation activation energy of martensite with temperature,which led to the varying nucleation rates of this model during martensitic transformation.According to the calculation results,the relative error of the modified model for the martensitic transformation kinetics curves of Fe-C-X(X = Ni,Cr,Mn,Si) alloys reached 9.5% compared with those measured via the thermal expansion method.The relative error was approximately reduced by two-thirds compared with that of the Magee model.The incorporation of nucleation activation energy into the kinetics model contributes to the improvement of its precision. 展开更多
关键词 Fe-C-X system martensitic transformation kinetics curve semi-empirical model nucleation activation energy
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Development of a rapid and efficient system for CR genes identification based on hairy root transformation in Brassicaceae
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作者 Wenlin Yu Lu Yang +12 位作者 Yuanyuan Xiang Rongde Li Xueqing Zhou Longcai Gan Xianyu Xiang Yunyun Zhang Lei Yuan Yanqing Luo Genze Li Youning Wang Yinhua Chen Peng Chen Chunyu Zhang 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第4期1049-1060,共12页
Many economically important crops and vegetables belonging to the cruciferous family are heavily endangered by clubroot disease caused by Plasmodiophora brassicae infection.Breeding of clubroot resistant cultivars bas... Many economically important crops and vegetables belonging to the cruciferous family are heavily endangered by clubroot disease caused by Plasmodiophora brassicae infection.Breeding of clubroot resistant cultivars based on mapping and cloning of resistant genes is commonly regarded as the most cost-effective and efficient way to fight against this disease.The traditional way of R gene functional validation requires stable transformation that is both time-and labor-consuming.In this study,a rapid and efficient hairy-root transgenic protocol mediated by Agrobacterium rhizogenes was developed.The transformation positive rate was over 80%in Brassica napus showed by GUS reporter gene and this transformation only took 1/6 of the time compared with stable transformation.The system was applicable to different B.napus varieties and other cruciferous crops including Brassica rapa and Brassica oleracea.In particular,two known CR genes,CRA3.7.1 and CRA8.2.4 were used respectively,as example to show that the system works well for CR gene study combined with subsequent P.brassicae infection in B.napus.Most importantly,it works both in over-expression that led to disease resistance,as well as in RNAi which led to disease susceptible phenotype.Therefore,this system can be used in batch-wise identification of CR genes,and also offered the possibility of manipulating key genes within the P.brassicae genome that could improve our knowledge on host-pathogen interaction. 展开更多
关键词 Brassicaceae Agrobacterium rhizogenes Hairy root transformation CLUBROOT Gene function
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Fast,simple,efficient Agrobacterium rhizogenes-mediated transformation system to non-heading Chinese cabbage with transgenic roots
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作者 Huiyu Wang Yushan Zheng +3 位作者 Qian Zhou Ying Li Tongkun Liu Xilin Hou 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第2期450-460,共11页
Non-heading Chinese cabbage, a variety of Brassica campestris, is an important vegetable crop in the Yangtze River Basin of China. However,the immaturity of its stable transformation system and its low transformation ... Non-heading Chinese cabbage, a variety of Brassica campestris, is an important vegetable crop in the Yangtze River Basin of China. However,the immaturity of its stable transformation system and its low transformation efficiency limit gene function research on non-heading Chinese cabbage. Agrobacterium rhizogenes-mediated(ARM) transgenic technology is a rapid and effective transformation method that has not yet been established for non-heading Chinese cabbage plants. Here, we optimized conventional ARM approaches(one-step and two-step transformation methods) suitable for living non-heading Chinese cabbage plants in nonsterile environments. Transgenic roots in composite non-heading Chinese cabbage plants were identified using phenotypic detection, fluorescence observation, and PCR analysis. The transformation efficiency of a two-step method on four five-day-old non-heading Chinese cabbage seedlings(Suzhouqing, Huangmeigui, Wuyueman, and Sijiu Caixin) was 43.33%-51.09%, whereas using the stout hypocotyl resulted in a transformation efficiency of 54.88% for the 30-day-old Sijiu Caixin.The one-step method outperformed the two-step method;the transformation efficiency of different varieties was above 60%, and both methods can be used to obtain transgenic roots for functional studies within one month. Finally, optimized ARM transformation methods can easily,quickly, and effectively produce composite non-heading Chinese cabbage plants with transgenic roots, providing a reliable foundation for gene function research and non-heading Chinese cabbage genetic improvement breeding. 展开更多
关键词 Agrobacterium rhizogenes Non-heading Chinese cabbage Transgenic roots Composite plant transformation efficiency
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Construction and Practice of Transformation System of Scientific and Technological Achievements in Agriculture:A Case Study of Chinese Academy of Tropical Agricultural Sciences
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作者 Xiaoyan ZHANG Huan OUYANG +1 位作者 Zirong LIAO Yishan ZHANG 《Asian Agricultural Research》 2024年第12期11-18,25,共9页
Accelerating the transformation of agricultural scientific and technological achievements is a key link in implementing innovation-driven development strategy and rural revitalization strategy,and improving developmen... Accelerating the transformation of agricultural scientific and technological achievements is a key link in implementing innovation-driven development strategy and rural revitalization strategy,and improving development quality and core competitiveness.How to build a scientific and systematic transformation system of scientific and technological achievements and improve the overall management level of scientific and technological achievements transformation of agricultural scientific research institutes is one of the key tasks to measure how a scientific research institute supports industry and serves society.Taking the Chinese Academy of Tropical Agricultural Sciences as an example,this paper explores the construction and practice of its scientific and technological achievements transformation system since the 13 th Five-Year Plan period.By arranging the current situation of resource elements for the transformation of scientific and technological achievements,analyzing the progress of the construction of the scientific and technological achievements transformation system,summarizing the practical results of the scientific and technological achievements transformation system,this paper puts forward 10 strategies and measures(implementing key projects for the transformation and application of scientific and technological achievements;striving to promote the transformation and application of on-duty scientific and technological achievements;accelerating the development and utilization of advantageous and characteristic resources;strengthening the use and protection of intellectual property rights;actively expanding cooperation activities between government,industry and research;increasing special financial support for the transformation of scientific and technological achievements;innovating state-owned asset management to accelerate scientific and technological development;piloting equity incentives to expand scientific and technological development channels to increase income;striving to create a relaxed environment for the transformation of scientific and technological achievements,effectively create scientific and technological value,enhance the development strength of the institute,and promote high-quality industrial development)in order to provide a useful reference for the transformation of scientific and technological achievements of agricultural research institutes. 展开更多
关键词 Scientific and technological achievements in agriculture transformation system CONSTRUCTION PRACTICE Chinese Academy of Tropical Agricultural Sciences
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Digital Transformation:The Impact of e-CNY on Securities Institutions and Financial Systems in China
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作者 Xinyue Mei 《Proceedings of Business and Economic Studies》 2024年第2期38-45,共8页
In recent years,the rapid advancement of emerging technologies such as big data,blockchain,and artificial intelligence has accelerated the transformation of currencies,shifting from materialization towards digitizatio... In recent years,the rapid advancement of emerging technologies such as big data,blockchain,and artificial intelligence has accelerated the transformation of currencies,shifting from materialization towards digitization and electronization.The e-CNY stands out as a prime example of China’s pioneering digital financial innovation globally.Governed by the central bank,it embodies the national agenda.As the e-CNY’s application field and reach expand,its relationship with the financial market grows increasingly intimate.As a significant participant in China’s financial landscape and a proactive responder to national policies,the securities industry is profoundly influenced by the e-CNY across various domains.Therefore,this paper undertakes a theoretical analysis of the e-CNY’s implementation within securities institutions,concluding that it will usher in a new paradigm for the entire financial system. 展开更多
关键词 e-CNY Securities institutions Digital transformation
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Stage IV malignant transformation of mature cystic teratoma palliatively treated with concurrent chemoradiotherapy:A case report
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作者 Saori Kondo Takashi Suzuki +4 位作者 Kanato Yoshiike Sakura Yamanaka Kenta Sonehara Hiroshi Nabeshima Osamu Oguchi 《World Journal of Clinical Cases》 SCIE 2025年第1期56-61,共6页
BACKGROUND Malignant transformation(MT)of mature cystic teratoma(MCT)has a poor prognosis,especially in advanced cases.Concurrent chemoradiotherapy(CCRT)has an inhibitory effect on MT.CASE SUMMARY Herein,we present a ... BACKGROUND Malignant transformation(MT)of mature cystic teratoma(MCT)has a poor prognosis,especially in advanced cases.Concurrent chemoradiotherapy(CCRT)has an inhibitory effect on MT.CASE SUMMARY Herein,we present a case in which CCRT had a reduction effect preoperatively.A 73-year-old woman with pyelonephritis was referred to our hospital.Computed tomography revealed right hydronephrosis and a 6-cm pelvic mass.Endoscopic ultrasound-guided fine-needle biopsy(EUS-FNB)revealed squamous cell carci-noma.The patient was diagnosed with MT of MCT.Due to her poor general con-dition and renal malfunction,we selected CCRT,expecting fewer adverse effects.After CCRT,her performance status improved,and the tumor size was reduced;surgery was performed.Five months postoperatively,the patient developed dis-semination and lymph node metastases.Palliative chemotherapy was ineffective.She died 18 months after treatment initiation.CONCLUSION EUS-FNB was useful in the diagnosis of MT of MCT;CCRT suppressed the disea-se and improved quality of life. 展开更多
关键词 Mature cystic teratoma Malignant transformation Squamous cell carcinoma Concurrent chemoradiotherapy Endoscopic ultrasound-guided fine-needle biopsy Case report
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Xiamen after 20 Years of Ecological Transformation
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作者 ZACHARY G.LUNDQUIST 《China Today》 2025年第1期66-68,共3页
The efforts Xiamen has made in ecological protection over the last 20 years have helped it become a beautiful and clean city.TWENTY years ago,I had the opportunity to travel to the city of Xiamen in southeastern China... The efforts Xiamen has made in ecological protection over the last 20 years have helped it become a beautiful and clean city.TWENTY years ago,I had the opportunity to travel to the city of Xiamen in southeastern China’s Fujian Province.Unfortunately,due to the fact that I was in a rush,I did not have the chance to see the whole city.My memory of Xiamen was its pleasant climate and unforgettable beauty-I knew if I ever got the opportunity,I would revisit this place.Twenty years went by until I was able to return to this city again.After emerging from the airport,I realized that I had grown older,while Xiamen was becoming increasingly youthful and vibrant.What exactly had given this city such vitality? 展开更多
关键词 ECOLOGICAL XIAMEN transformation
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Establishment of Protoplast Transformation System in Alternaria tenuissima Using G418 Selection Marker 被引量:4
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作者 万英 张大军 +1 位作者 黄云 蒋伶活 《Agricultural Science & Technology》 CAS 2008年第3期59-62,98,共5页
[Objective] The study aimed to establish a protoplast transformation system in Alternaria tenuissima. [Method] The protoplast of A.tenuissima was firstly prepared by enzymolysis method; then the yielded protoplast was... [Objective] The study aimed to establish a protoplast transformation system in Alternaria tenuissima. [Method] The protoplast of A.tenuissima was firstly prepared by enzymolysis method; then the yielded protoplast was transformed by G418 resistant DNA plasmid using PEG/CaCl2 method. [Result] The growth phenotype and PCR detection showed that resistance gene had integrated into A.tenuissima genome. The transformation efficiency of this method reached per μg DNA 3-4 transformants. After subculture thrice under nonselective condition, G418 resistance could still inherit stably. [Conclusion] The transformation system of A.tenuissima was successfully established, which laid basis for studying of the gene function of Alternaria tenuissima. 展开更多
关键词 ALTERNARIA tenuissima G418 RESISTANCE PROTOPLAST transformation
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Combined Method of Datum Transformation Between Different Coordinate Systems 被引量:4
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作者 王晓妮 张洁 《Geo-Spatial Information Science》 2002年第4期5-9,共5页
The similarity transformation model between different coordinate systems is not accurate enough to describe the discrepancy of them.Therefore,the coordinate transformation from the coordinate frame with poor accuracy ... The similarity transformation model between different coordinate systems is not accurate enough to describe the discrepancy of them.Therefore,the coordinate transformation from the coordinate frame with poor accuracy to that with high accuracy cannot guarantee a high precision of transformation.In this paper,a combined method of similarity transformation and regressive approximating is presented.The local error accumulation and distortion are taken into consideration and the precision of coordinate system is improved by using the recommended method 展开更多
关键词 coordinate transformation similarity transformation regressive approximating
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Optimization of Genetic Transformation System of Tobacco K326 Mediated by Agrobacterium 被引量:2
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作者 赵勤 《Agricultural Science & Technology》 CAS 2011年第1期62-64,共3页
[Objective]The aim was to optimize genetic transformation system in tobacco K326 mediated by Agrobacterium.[Method]The leaf of tobacco aseptic seedling was taken as explants to study the optimization of Agrobacterium-... [Objective]The aim was to optimize genetic transformation system in tobacco K326 mediated by Agrobacterium.[Method]The leaf of tobacco aseptic seedling was taken as explants to study the optimization of Agrobacterium-mediated genetic transformation system.[Result] The highest transformation efficiency was obtained when the explants were pre-cultured in the medium of MS + 2 mg/L 6-BA + 0.2 mg/L IAA for 2 d,and then infected with Agrobacterium GV3101(OD600 =0.6) for 5 min.The PCR detection proved that npt II gene had been integrated into the regenerated tobacco plants.[Conclusion]A highly efficient genetic transformation system of tobacco leaf mediated by Agrobacterium was established. 展开更多
关键词 Agrobacterium tumefaciens TOBACCO Genetic transformation
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Establishment of the Agrobacterium-mediated Genetic Transformation System of Ginkgo biloba and the Construction of the Expression Vector of Gb-DXR
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作者 冯国庆 杨颖舫 +4 位作者 李郑娜 成瑜 杨春贤 陈敏 廖志华 《Agricultural Science & Technology》 CAS 2010年第3期28-32,114,共6页
[Objective] The research aimed to provide reference for increasing the genetic transformation efficiency of Ginkgo biloba mediated by Agrobacterium.[Method] Taking the mature embryos of Ginkgo biloba seeds as explants... [Objective] The research aimed to provide reference for increasing the genetic transformation efficiency of Ginkgo biloba mediated by Agrobacterium.[Method] Taking the mature embryos of Ginkgo biloba seeds as explants,after 48 hours' pre-cultivation on MS medium in the absence of phytohormone,GUS gene was transmitted into embryos of Ginkgo biloba mediated by three kinds of Agrobacterium.Transient expression of GUS gene activity was observed through histochemical staining,and the influencing factors of the expression of GUS gene were analyzed.And the expression vector of 1-deoxy-D-xylulose-5-phosphate reductoisomerase in the biosynthesis approach of biobalide precursor of Ginkgo biloba was constructed.[Result] A more suitable genetic transformation scheme was obtained as follows:taking embryos of Ginkgo biloba as explants,using EHA105 Agrobacterium with pCAMBIA1304+ for infection,co-culture for 3 days and GUS staining.The results showed that transient expression rate of GUS after transformation was higher.[Conclusion] The research provide a more effective method for further study on the transgene of Ginkgo biloba. 展开更多
关键词 Embryos of Ginkgo biloba AGROBACTERIUM-MEDIATED Genetic transformation GUS gene 1-deoxy-D-xylulose-5-phosphate reductoisomerase Expression vector
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ORDERING TRANSFORMATION OF γ TO γ_1 IN TiAl+Nb SYSTEM
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作者 王金国 陈国良 叶恒强 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 1995年第1期6+1-6,共7页
A series of TiAl+Nb alloys with various Nb contents has been employed to explore phase relationship and the evolution of microstructure.A new ordered γ derivative (γ1) has been observed in the alloy containing 20 at... A series of TiAl+Nb alloys with various Nb contents has been employed to explore phase relationship and the evolution of microstructure.A new ordered γ derivative (γ1) has been observed in the alloy containing 20 at% Nb.The additional diffraction spots added to the diffraction pattern of L10 (TiAl) structure have been found in the alloy containing Nb up to 11 at% in terms of further ordering.The transformation from L10 (TiAl) structure to the further ordering phase,γ1,is a continuous ordering process with the substitution of Nb atoms for Ti atoms in alloys with over-stoichiometric Al content of TiAl.The possible transformtion characterzation has been discussed. 展开更多
关键词 INTERMETALLICS Ti-Al-Nb system SUPERSTRUCTURE ordering transformation
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Optimization of Agrobacterium Mediated Genetic Transformation System of Tomato Meifen No.1
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作者 李立芹 《Agricultural Science & Technology》 CAS 2010年第11期92-94,共3页
[Objective] The aim of this study was to carry out study on the optimization of Agrobacterium mediated genetic transformation system of tomato Meifen No.1.[Method] The cotyledon of tomato cultivar Meifen No.1 was used... [Objective] The aim of this study was to carry out study on the optimization of Agrobacterium mediated genetic transformation system of tomato Meifen No.1.[Method] The cotyledon of tomato cultivar Meifen No.1 was used as the explant,and the Agrobacterium mediation method was used to optimize its genetic transformation efficiency so as to establish the efficient Agrobacterium mediated genetic transformation system of tomato cotyledon.[Result] The highest transformation efficiency was obtained when the explants were cultivated for 2 d on MS + 2.0 mg/L 6-BA+ 0.5 mg/L IAA medium and then infected with Agrobacterium EHA105(OD = 0.4)for 5 min;it was proved by PCR analysis that the target nptII gene had been integrated into the genome of regenerated plants.[Conclusion] The result in this study had provided basis for the transfer of valuable genes into tomato Meifen No.1. 展开更多
关键词 Agrobacterium tumefaciens TOMATO Transgenic transformation
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Transjugular intrahepatic portosystemic shunt for the prevention of recurrent esophageal variceal bleeding in patients with cavernous transformation of portal vein 被引量:14
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作者 Zhao-Peng Li Sui-Sui Wang +3 位作者 Guang-Chuan Wang Guang-Jun Huang Jing-Qin Cao Chun-Qing Zhang 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2018年第6期517-523,共7页
Background: Treatment options for patients with cavernous transformation of portal vein(CTPV) are limited. This study aimed to evaluate the feasibility, efficacy and safety of transjugular intrahepatic portosystemic s... Background: Treatment options for patients with cavernous transformation of portal vein(CTPV) are limited. This study aimed to evaluate the feasibility, efficacy and safety of transjugular intrahepatic portosystemic shunt(TIPS) to prevent recurrent esophageal variceal bleeding in patients with CTPV. Methods: We retrospectively analyzed 67 consecutive patients undergone TIPS from January 2011 to December 2016. All patients were diagnosed with CTPV. The indication for TIPS was a previous episode of variceal bleeding. The data on recurrent bleeding, stent patency, hepatic encephalopathy and survival were retrieved and analyzed. Results: TIPS procedure was successfully performed in 56 out of 67(83.6%) patients with CTPV. TIPS was performed via a transjugular approach alone( n = 15), a combined transjugular/transhepatic approach( n = 33) and a combined transjugular/transsplenic approach( n = 8). Mean portosystemic pressure gradient(PSG) decreased from 28.09 ± 7.28 mmHg to 17.53 ± 6.12 mmHg after TIPS( P < 0.01). The probability of the remaining free recurrent variceal bleeding was 87.0%. The probability of TIPS patency reached 81.5%. Hepatic encephalopathy occurrence was 27.8%, and survival rate was 88.9% until the end of follow-up. Four out of 11 patients who failed TIPS died, and 4 had recurrent bleeding. Conclusions: TIPS should be considered a safe and feasible alternative therapy to prevent recurrent esophageal variceal bleeding in patients with CTPV, and to achieve clinical improvement. 展开更多
关键词 Cavernous transformation Portal vein Transjugular intrahepatic portosystemic shunt Variceal rebleeding Portal hypertension
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Development of Alfalfa (Medicago sativa L.) Regeneration System and Agrobacterium-Mediated Genetic Transformation 被引量:10
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作者 ZHANG He HUANG Qi-man SU Jin 《Agricultural Sciences in China》 CAS CSCD 2010年第2期170-178,共9页
The regeneration ability of four alfalfa (Medicago sativa L.) cultivars, Xinjiang Daye, Longdong, Gannong 1 and Gannong 3, was studied, and the effects of various cultivars, explant sources and medium recipes on reg... The regeneration ability of four alfalfa (Medicago sativa L.) cultivars, Xinjiang Daye, Longdong, Gannong 1 and Gannong 3, was studied, and the effects of various cultivars, explant sources and medium recipes on regeneration were compared. The better callus forming frequency obtained from hypocotyls of Xinjiang Daye is 88.5% and regeneration frequency is 9.8% in our initial experiments. To further optimize regeneration system for genetic transformation, we therefore changed concentrations of plant growth regulators and supplemented with glutamine into callus-induction and shoot-regeneration media. Callus forming frequency and shoot differentiation frequency were increased to 100%. The time taken to generate transgenic plants (16 weeks) was shorter than that for previouse procedure (25 weeks) and regeneration frequency was promoted to 15.1%. The results show that addition of glutamine is particularly important for shortening period of regeneration and promoting regeneration frequency. For study of genetic transformation of alfalfa, Agrobacterium tumefaciens-mediated transformation of Xinjiang Daye was developed based on this optimized regeneration system. The plant expression vector carrying two glutamine synthetases (GS 1 and GS2) and △1-pyrroline-5-carboxylate synthetase (P5CS) gene was used for alfalfa in vitro transformation. Six transgenic alfalfa plantlets with resistance to PPT were obtained. The introduction of foreign genes into plants was assessed in the transformants by PCR analysis and Southern hybridizations. 展开更多
关键词 alfalf glutamine synthetases △1-pyrroline-5-carboxylate synthetase Agrobacterium tumefaciens-mediated transformation transgenic alfalfa
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Generalized canonical transformation for second-order Birkhoffian systems on time scales 被引量:5
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作者 Y.Zhang X.H.Zhai 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2019年第6期353-357,共5页
The theory of time scales,which unifies continuous and discrete analysis,provides a powerful mathematical tool for the study of complex dynamic systems.It enables us to understand more clearly the essential problems o... The theory of time scales,which unifies continuous and discrete analysis,provides a powerful mathematical tool for the study of complex dynamic systems.It enables us to understand more clearly the essential problems of continuous systems and discrete systems as well as other complex systems.In this paper,the theory of generalized canonical transformation for second-order Birkhoffian systems on time scales is proposed and studied,which extends the canonical transformation theory of Hamilton canonical equations.First,the condition of generalized canonical transformation for the second-order Birkhoffian system on time scales is established.Second,based on this condition,six basic forms of generalized canonical transformation for the second-order Birkhoffian system on time scales are given.Also,the relationships between new variables and old variables for each of these cases are derived.In the end,an example is given to show the application of the results. 展开更多
关键词 BIRKHOFFIAN systems GENERALIZED CANONICAL transformation Time scales CALCULUS Generating function
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Optimization of Agrobacterium tumefaciens-Mediated Immature Embryo Transformation System and Transformation of Glyphosate-Resistant Gene 2mG2-EPSPS in Maize(Zea mays L.) 被引量:4
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作者 YU Gui-rong LIU Yan +8 位作者 DU Wen-ping SONG Jun LIN Min XU Li-yuan XIAO Fang-ming LIU Yong-shengKey Laboratory for Bio-Resource and Eco-Environment Ministry of Education/State Key Laboratory of Hydraulics and Mountain River Engineering College of Life Science Sichuan University 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第12期2134-2142,共9页
Since maize is one of the most important cereal crops in the world,establishment of an efficient genetic transformation system is critical for its improvement.In the current study,several elite corn lines were tested ... Since maize is one of the most important cereal crops in the world,establishment of an efficient genetic transformation system is critical for its improvement.In the current study,several elite corn lines were tested for suitability of Agrobacterium tumefaciens-mediated transformation by using immature embryos as explants.Infection ability and efficiency of transformation of A.tumefaciens sp.strains EHA105 and LBA4404,different heat treatment times of immature embryos before infection,influence of L-cysteine addition in co-cultivation medium after transformation,and how different ways of selection and cultivation influence the efficiency of transformation were compared.Glyphosate-resistant gene 2mG2-EPSPS was transformed into several typical maize genotypes including 78599,Zong 31 and BA,under the optimum conditions.Results showed that the hypervirulent Agrobacterium tumefaciens sp.strain EHA105 was more infectious than LBA4404.Inclusion of L-cysteine(100 mg L-1) in co-cultivation medium,and heating of the immature embryos for 3 min prior to infection led to a significant increase in the transformation efficiency.Growth in resting medium for 4-10 d and delaying selection was beneficial to the survival of resistant calli.During induction of germination,adding a high concentration of 6-BA(5 mg L-1) and a low concentration of 2,4-D(0.2 mg L-1) to regeneration medium significantly enhanced germination percentage.Using the optimized transformation procedure,more than 800 transgenic plants were obtained from 78599,Zong 31 and BA.By spraying herbicide glyphosate on leaves of transgenic lines,we identified 66 primary glyphosate-resistant plants.The transformation efficiency was 8.2%.PCR and Southern-blot analyses confirmed the integration of the transgenes in the maize genome. 展开更多
关键词 MAIZE immature embryo Agrobacterium tumefaciens-mediated transformation transgenic approach glyphosate resistance
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Establishment of A Simple and Efficient Agrobacterium-mediated Genetic Transformation System to Chinese Cabbage(Brassica rapa L.ssp.pekinensis) 被引量:6
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作者 Xiaonan Li Haiyan Li +3 位作者 Yuzhu Zhao Peixuan Zong Zongxiang Zhan Zhongyun Piao 《Horticultural Plant Journal》 SCIE CSCD 2021年第2期117-128,共12页
Chinese cabbage,belonging to Brassica rapa species,is an important vegetable in Eastern Asia.It is well known that Chinese cabbage is quite recalcitrant to genetic transformation and the transgenic frequency is genera... Chinese cabbage,belonging to Brassica rapa species,is an important vegetable in Eastern Asia.It is well known that Chinese cabbage is quite recalcitrant to genetic transformation and the transgenic frequency is generally low.The lack of an efficient and stable genetic transformation system for Chinese cabbage has largely limited related gene functional studies.In this study,we firstly developed a regeneration system for Chinese cabbage by optimizing numerous factors,with 93.50%regeneration rate on average.Based on this,a simple and efficient Agrobacteriummediated genetic transformation methodwas established,without pre-culture procedure and concentration adjustment of hormone and AgNO_(3) in co-cultivation and selection media.Using this system,transformants could be obtained within 3.5–4.0 months.Average transformation frequency is up to 10.83%.The establishment of this simple and efficient genetic transformation method paved the way for further gene editing and functional studies in Chinese cabbage. 展开更多
关键词 Chinese cabbage Agrobacterium tumefaciens genetic transformation
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