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Amplification and function analysis of N6-adenine-specific DNA methyltransferase gene in Nilaparvata lugens

Journal of Integrative Agriculture 2016年第3期15卷 591-599页

作者： ZHANG Jiao xing yan-ru HOU Bo-feng YUAN Zhu-ting LI Yao JIE Wen-cai SUN yang LI Fei Department of Entomology College of Plant Protection Nanjing Agricultural UniversityKey Laboratory of Monitoring and Management of Plant Diseases and Insects Ministry of Agriculture Key Lab of Agricultural Entomology Ministry of AgricultureInstitute of Insect Sciences Zhejiang University

Methylation of the N6 position of adenine, termed N6-methyladenine, protects DNA from restriction endonucleases via the host-specific restriction-modification system. N6-methyladenine was discovered and has been well studied in bacteria. N6-adenine-specific DNA methyltransferase（N6AMT） is the main enzyme catalyzing the methylation of the adenine base and knowledge of this enzyme was mainly derived from work in prokaryotic models. However, large-scale gene discovery at the genome level in many model organisms indicated that the N6AMT gene also exists in eukaryotes, such as humans, mice, fruit flies and plants. Here, we cloned a N6AMT gene from Nilaparvata lugens（Nlu-N6AMT） and amplified its fulllength transcript. Then, we carried out a systematic investigation of N6AMT in 33 publically available insect genomes, indicating that all studied insects had N6AMT. Genomic structure analysis showed that insect N6AMT has short introns compared with the mammalian homologs. Domain and phylogenetic analysis indicated that insect N6AMT had a conserved N6-adenine Mlase domain that is specific to catalyze the adenine methylation. Nlu-N6AMT was highly expressed in the adult female. We knocked down Nlu-N6AMT by feeding ds RNA from the second instar nymph to adult female, inducing retard development of adult female. In all, we provide the first genome-wide analysis of N6AMT in insects and presented the experimental evidence that N6AMT might have important functions in reproductive development and ovary maturation.

关键词： N6-adenine-specific DNA methyltransferase(N6AMT) Nilaparvata lugens expression RNA interference gene structure

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Somatic Embryogenesis and Plant Regeneration from Two Recalcitrant Genotypes of Gossypium hirsutum L.

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Agricultural Sciences in China 2006年第5期5卷 323-329页

作者： WANG yan-xia WANG xing-fen MA Zhi-ying ZHANG Gui-yin HAN Gai-ying Hebei Agricultural University/Key Laboratory of Crop Germplasm Resources of Hebei Baoding 071001 P.R. China

An improved protocol has been developed for somatic embryogenesis and plant regeneration of recalcitrant cotton cultivars. High callus frequencies and embryogenic tissue were developed in MSB medium supplemented with gradient concentrations of KT and 2,4-D, their concentration decreasing from 0.1 to 0.01 mg·L^-1. Somatic embryos were successfully incubated in 1/2 macronutrient MSB suspension supplemented with 0.5 g· L^-1 glutamine and 0.5 g·L^-1 asparagine. Decrease in macronutrient concentration of MSB significantly alleviated browning and was beneficial to suspension cells. Transformation of somatic embryos into plants was induced in MSB medium supplemented with 3% sucrose, 0.5 g·L^-1 glutamine, 0.5 g·L^-1 asparagine, and 6.0 g·L^-1 agar. The effect of sucrose as carbohydrate was better than that of glucose for plant germination. Using this protocol, regenerated plantlets from the CCRI521 and Zhongzhi86-6 reached to as much as 19.6 and 18.5% somatic embryos, respectively.

关键词： Gossypium hirsutum L. recalcitrant genotypes plant regeneration somatic embryogenesis effect of macronutrients suspension culture

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Estimating Soil Erosion in Northeast China Using ^(137)Cs and ^(210)Pbex

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Pedosphere 2011年第6期21卷 706-711页

作者： yanG Yu-Hong yan Bai-xing ZHU Hui Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130012 （China） College of Water Resources North China University of Water Resources and Electric Power Zhengzhou 450011 （China）

Evaluation of soil erosion in agricultural fields is valuable to develop conservation practices for reducing agricultural nonpoint source pollution. Soil erosion rates were quantified using the fallout radionuclide tracer technique in Mojiagou Basin located on the outskirts of Changchun in Northeast China. The calculated soft erosion rates in the study area were 1.99 and 1.85 mm year-1 using 137Cs and excess 210pb （210Pbex） measurements, respectively. Both fallout radionuclides showed a similar tendency at downslope sites. All measured sites have experienced net erosion during the past 50 to 100 years. 137Cs and 210Pbex measurements were useful to quantify soil erosion rates on field and small basin scales. At this rate of erosion, the current fertile topsoil layer would be entirely removed within 70 years.

关键词： black soil fallout radionuclide tracer technique rainfall erosivity reference inventory soil loss

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A Knowledge Model System for Wheat Production Management

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Pedosphere 2007年第2期17卷 172-181页

作者： ZHU yan CAO Wei-xing DAI Ting-Bo TIAN Yong-Chao YAO Xia Hi-Tech Key Laboratory of Information Agriculture of Jiangsu Province Nanjing Agricultural University Nanjing 210095 （China）. Key Laboratory of Crop Growth Regulation of Ministry of Agriculture Nanjing Agricultural University Nanjing 210095 （China）

A knowledge model with temporal and spatial characteristics for the quantitative design of a cultural pattern in wheat production, using systems analysis and dynamic modeling techniques, was developed for wheat management, as a decision-making tool in digital farming. The fundamental relationships and algorithms of wheat growth indices and management criteria to cultivars, ecological environments, and production levels were derived from the existing literature and research data to establish a knowledge model system for quantitative wheat management using Visual C^＋＋. The system designed a cultural management plan for general management guidelines and crop regulation indices for timecourse control criteria during the wheat-growing period. The cultural management plan module included submodels to determine target grain yield and quality, cultivar choice, sowing date, population density, sowing rate, fertilization strategy, and water management, whereas the crop regulation indices module included submodels for suitable development stages, dynamic growth indices, source-sink indices, and nutrient indices. Ewluation of the knowledge model by design studies on the basis of data sets of different eco-sites, cultiwrs, and soil types indicated a favorable performance of the model system in recommending growth indices and management criteria under diverse conditions. Practical application of the knowledge model system in comparative field experiments produced yield gains of 2.4% to 16.5%. Thus, the presented knowledge model system overcame some of the difficulties of the traditional wheat management patterns and expert systems, and laid a foundation for facilitating the digitization of wheat management.

关键词： expert system knowledge model quantitative decision-making regulation index wheat

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H6 Non-isolated Full Bridge Grid-connected PV Inverters With Low Leakage Currents

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中国电机工程学报 2012年第15期32卷 I0001-I0022,21页

作者： ZHANG Li SUN Kai FENG Lanlan xing yan XU Ming Nanjing University of Aeronautics ＆ Astronautics Tsinghua University

为满足非隔离光伏并网发电系统对共模漏电流的限制，提出一种六开关逆变器拓朴（H6拓扑）。所提出的H6拓扑在功率传输模态时，进网电流半个工频周期流过3支开关管，而另半个工频周期流过2支开关管，故相对于H5拓扑，降低了通态损耗，有... 详细信息

为满足非隔离光伏并网发电系统对共模漏电流的限制，提出一种六开关逆变器拓朴（H6拓扑）。所提出的H6拓扑在功率传输模态时，进网电流半个工频周期流过3支开关管，而另半个工频周期流过2支开关管，故相对于H5拓扑，降低了通态损耗，有利于热应力均衡，且仍满足续流阶段光伏电池输出端与电网脱离的要求。详细分析拓扑的工作原理，并推论给出H6非隔离光伏并网逆变器的其它3种拓扑结构；比较分析了H5拓扑、Heric拓扑和H6拓扑的损耗和成本。通过1kW通用样机平台对比验证了上述3种拓扑的效率和共模特性。实验结果表明，H6拓扑的变换效率高于H5拓扑、但略低于Heric拓扑，共模特性优于Heric拓扑、但略劣于H5拓扑。

关键词：全桥逆变器并网逆变器漏电流共模电压光伏发电

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CHEMICAL CHARACTERISTICS OF WATER ENVIRONMENT IN LIMNIC WETLANDS IN THE WESTERN SONGNEN PLAIN, CHINA

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Chinese Geographical Science 2000年第4期10卷 90-95页

作者： Xin-shan Song Bai-xing yan Wei Deng Jin-liang Zhai Changchun Institute of Geography the Chinese Academy of Sciences Changchun P. R. China

In the western Songnen Plain in China, the alkalization degree of water bodies is high in the limnic wetlands. Generally, pH is above 8.0, and the hydrochemical types belong to HCO32--Na＋ . Through analysis on the basic saline variables such as CO32-, HCO32-, Cl-, Ca2＋ , Mg2＋ , SO42-, Na＋ etc. and the composed variables such as （ Cl-＋ SO42-） / HCO32-and Na＋ /（ Ca2＋＋ Mg2＋） , the relationships between different variables were found, and the discriminant function and critical region map based on the pH value are obtained, and the function could be applied as one of the significant study methods on the investigation of saline-alkaline water-body. The relative analysis shows that the correlations are different among different salt variables, and some of them reaches significant level (α =0.01). Specially, in the western Songnen Plain, the lithofacies material of soil is mainly formed by the weathering of basalt and granite, and they are deposited inside the plain through running water transportation, so the NaAlO2, Na2SiO3 and NaHSiO3 in them can react with water and carbonate to form soda, which leads to the high correlations between Na＋ and CO32-, HCO32-, Cl-, SO42-, and the correlation between Na＋ and Na＋ /（ Ca2＋＋ Mg2＋） is the highest. Moreover, because of high evaporation, the salts that are in the groundwater is congregated on the earth’s surface, the dissoluble salts (Cl-,SO42-) turn into lake, which accounts for the reason for the high correlation between Cl-and SO42-.

关键词： limnic wetlands hydrochemical types correlation analysis discriminantion analysis

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Computer aided diabetic retinopathy detection based on ophthalmic photography: a systematic review and Meta-analysis

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International Journal of Ophthalmology(English edition) 2019年第12期12卷 1908-1916页

作者： Hui-Qun Wu yan-xing Shan Huan Wu Di-Ru Zhu Hui-Min Tao Hua-Gen Wei Xiao-yan Shen Ai-Min Sang Jian-Cheng Dong Departm ent of Medical Informatics Medical School of Nantong UniversityNantong 226001Jiangsu ProvinceChina School o f Information Science and Technology Nantong UniversityNantong 226001Jiangsu ProvinceChina Department of Ophthalmology Affiliated Hospital of Nantong UniversityNantong 226001Jiangsu ProvinceChina

AIM: To ensure the diagnostic value of computer aided techniques in diabetic retinopathy(DR) detection based on ophthalmic photography(OP). METHODS: PubM ed, EMBASE, Ei village, IEEE Xplore and Cochrane Library database were searched systematically for literatures about computer aided detection(CAD) in DR detection. The methodological quality of included studies was appraised by the Quality Assessment Tool for Diagnostic Accuracy Studies(QUADAS-2). Meta-Di Sc was utilized and a random effects model was plotted to summarize data from those included studies. Summary receiver operating characteristic curves were selected to estimate the overall test performance. Subgroup analysis was used to identify the efficiency of CAD in detecting DR, exudates(EXs), microaneurysms(MAs) as well as hemorrhages(HMs), and neovascularizations(NVs). Publication bias was analyzed using STATA. RESULTS: Fourteen articles were finally included in this Meta-analysis after literature review. Pooled sensitivity and specificity were 90%(95%CI, 85%-94%) and 90%(95%CI, 80%-96%) respectively for CAD in DR detection. With regard to CAD in EXs detecting, pooled sensitivity, specificity were 89%(95%CI, 88%-90%) and99%(95%CI, 99%-99%) respectively. In aspect of MAs and HMs detection, pooled sensitivity and specificity of CAD were 42%(95%CI, 41%-44%) and 93%(95%CI, 93%-93%) respectively. Besides, pooled sensitivity and specificity were 94%(95%CI, 89%-97%) and 87%(95%CI, 83%-90%) respectively for CAD in NVs detection. No potential publication bias was observed. CONCLUSION: CAD demonstrates overall high diagnostic accuracy for detecting DR and pathological lesions based on OP. Further prospective clinical trials are needed to prove such effect.

关键词： Meta-analysis diabetic retinopathy computer aided detection

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Role of CXCL12 in metastasis of human ovarian cancer

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Chinese Medical Journal 2007年第14期120卷 1251-1255页

作者： JIANG Yu-ping WU Xiao-hua xing Han-ying DU xing-yan Department of Obstetrics and Gynecology Second Hospital of Hebei Medical University Shijiazhuang 050000 China Department of Obstetrics and Gynecology Second Hospital of Hebei Medical University Shijiazhuang 050011 China Clinical Medical Research Center Hebei General Hospital Shijiazhuang 050000 China Department of Haematology Fourth Hospital of Hebei Medical University Shijiazhuang 050000 China

Background In a previous study, we have verified that CXCR4 expression is correlated with tumor aggressive progression and poor prognosis in patients with epithelial ovarian cancer. The aim of this study was to explore the effect of CXCL12-CXCR4 axis on the metastasis of human ovarian cancer. Methods The expressions of CXCR4 and CXCL12 mRNA and protein in human ovarian cancer cell line CAOV-3 was detected by RT-PCR and immunocytochemistry. *** （MTT） was used to analyze the effect of different concentrations of CXCL12 on the proliferation of CAOV-3 cells. Transwell invasion chamber and matrigel were used to evaluate the effect of various concentrations of CXCL12 and ascites on the migration and invasion of CAOV-3 cells. The expressions of integrin β1 and vascular endothelial growth factor-C （VEGF-C） mRNA were detected by RT-PCR. Data were analyzed using ANOVA by SAS 6.12. Results Under serum-free suboptimal culture conditions, CXCL12 （100 ng/ml） significantly enhanced the proliferation of CAOV-3 cells compared with the control and 10 ng/ml CXCL12 groups （0.428 ± 0.051 vs. 0.325 ±0.045 and 0.328±0.039, P〈0.05）. This enhancing effect of CXCL12 was significantly inhibited by 10 μg/ml neutralizing CXCR4 antibody or 1 μg/ml CXCR4 antagonist AMD3100. However, 10 μg/ml neutralizing CXCR4 antibody could not inhibit cell proliferation without CXCL12. The levels of migration and invasion of the CAOV-3 cells treated with 100 ng/ml CXCL12 were significantly higher than those in the control （migration： 523.3± 25.2 vs 108.0 ± 7.2; invasion： 39.3 ± 4.0 vs. 4.0 ± 1.0）. The enhancing effect of CXCL12 on cell migration and invasion increased with the concentration of CXCL12 （100 ng/ml vs 10 ng/ml： migration, 523.3 ± 25.2 vs 211.7 ± 24.7; invasion, 39.3 ± 4.0 vs 15.7 ± 3.1, P〈0.05）, and was strongly inhibited by 10 μg/ml neutralizing CXCR4 antibody or 1 μg/ml AMD3100. The number of migrated and invading cells in the CAOV-3 added with ascites was significantl

关键词： ovarian cancer metastasis CXCL12

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基于沙漠环境的铁路GSM-R系统传播模型研究

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铁道学报 2014年第7期36卷 70-73页

作者：徐岩严星涛兰州交通大学电子与信息工程学院甘肃兰州730070

沙漠中的沙尘暴或风沙天气对无线通信有重要的影响,随着我国越来越多的高速铁路沙漠中建成,研究在沙尘暴、沙尘天气下GSM-R通信系统的传播模型对于保证GSM-R通信的安全和稳定有十分重要的意义。本文结合太原-中卫-银川铁路毛乌素沙漠南... 详细信息

沙漠中的沙尘暴或风沙天气对无线通信有重要的影响,随着我国越来越多的高速铁路沙漠中建成,研究在沙尘暴、沙尘天气下GSM-R通信系统的传播模型对于保证GSM-R通信的安全和稳定有十分重要的意义。本文结合太原-中卫-银川铁路毛乌素沙漠南端定边至银川区段GSM-R通信系统,对沙漠环境沙尘粒子的散射产生的路径损耗进行了分析,将传统路径损耗模型与实际测量数据进行了误差研究,对路径损耗模型的参数因子进行了调整和优化,通过仿真实验与结果的分析,证明该改进模型能更加逼近实际测量数据。

关键词：铁路移动通信系统沙漠环境路径损耗散射

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17α-hydroxylase/17,20 carbon chain lyase deficiency caused by ***329fs homozygous mutation:Three case reports

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World Journal of Clinical Cases 2021年第8期9卷 1923-1930页

作者： Dai Zhang Jian-Ran Sun Jiang Xu yan xing Mao Zheng Shan-Dong Ye Jie Zhu Department of Endocrinology The First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001Anhui ProvinceChina Department of Endocrinology Endocrinology Laboratory of the First Affiliated Hospital of USTCHefei 230001Anhui ProvinceChina

***329fs is a cytochrome P450c17 mutation among Chinese ***,data on 17-α-hydroxylase deficiency caused by cytochrome P450c17 ***329fs homozygous mutation are *** paper is a case report of three patients homozygous for ***329fs who were diagnosed with 17-α-hydroxylase deficiency between 2005 and *** SUMMARY Case 1 presented with hypertension,hypokalemia,sexual infantilism and delayed bone *** patient had a 46,XY karyotype,was homozygous for ***329fs and was recently treated with dexamethasone 0.375 mg *** 2 presented with hypokalemia,sexual infantilism,osteoporosis and delayed bone *** patient had a 46,XY karyotype,was homozygous for ***329fs and was treated with dexamethasone 0.75 mg qn at the last *** potassium and blood pressure could be maintained within normal range for cases 1 and *** 3 presented with amenorrhea,sexual infantilism,osteopenia and delayed bone *** patient had a 46,XX karyotype,was homozygous for ***329fs and was treated with dexamethasone 0.75 mg qn and progynova 1 mg *** follow-up revealed an adrenocorticotropic hormone(8 AM)of<5.00 pg/*** The homozygous ***329fs mutation usually manifests as a combined deficiency,and definitive diagnosis depends primarily on genetic testing.

关键词： Cytochrome P450c17 17-α-hydroxylase-17,20-lyase deficiency Phenotype Mutation Case report

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