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Molecular cloning,characterization and promoter analysis of LbgCWIN1 and its expression profiles in response to exogenous sucrose during in vitro bulblet initiation in lily
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作者 Cong Gao Shiqi Li +4 位作者 Yunchen Xu Yue Liu Yiping Xia Ziming Ren Yun Wu 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第2期545-555,共11页
Lily(Lilium spp.) is an important ornamental flower, which is mainly propagated by bulbs. Cell wall invertases(CWINs), which catalyze the irreversibly conversion of sucrose into glucose and fructose in the extracellul... Lily(Lilium spp.) is an important ornamental flower, which is mainly propagated by bulbs. Cell wall invertases(CWINs), which catalyze the irreversibly conversion of sucrose into glucose and fructose in the extracellular space, are key enzymes participating in sucrose allocation in higher plants. Previous studies have shown that CWINs play an essential role in bulblet initiation process in bulbous crops, but the underlying molecular mechanism remains unclear. Here, a CWIN gene of Lilium brownii var. giganteum(Lbg) was identified and amplified from genomic DNA. Quantitative RT-PCR assays revealed that the expression level of LbgCWIN1 was highly upregulated exactly when the endogenous starch degraded in non-sucrose medium during in vitro bulblet initiation in Lbg. Phylogenetic relationship, motif, and domain analysis of LbgCWIN1 protein and CWINs in other plant species showed that all sequences of these CWIN proteins were highly conserved. The promoter sequence of LbgCWIN1 possessed a number of alpha-amylase-, phytohormone-, light-and stress-responsive cis-elements. Meanwhile, β-glucuronidase(GUS) assay showed that the 459 bp upstream fragment from the translational start site displayed maximal promoter activity. These results revealed that LbgCWIN1 might function in the process of in vitro bulblet initiation and be in the response to degradation of endogenous starch. 展开更多
关键词 Lilium brownii var.giganteum LbgCWIN1 Phylogenetic analysis Promoter analysis Bulblet initiation
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Qualitative analysis of aromatic compounds via 1D TOCSY techniques
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作者 Wenbo Dong Qi Zhao +3 位作者 Jiancheng Zhao Jiarong Zhang Yingxiong Wang Yan Qiao 《Magnetic Resonance Letters》 2024年第1期21-27,共7页
The aromatic compounds,including o-xylene,m-xylene,p-xylene,and ethylbenzene,primarily originate from the catalytic reforming of crude oil,and have a wide variety of applications.However,because of similar physical an... The aromatic compounds,including o-xylene,m-xylene,p-xylene,and ethylbenzene,primarily originate from the catalytic reforming of crude oil,and have a wide variety of applications.However,because of similar physical and chemical properties,these compounds are difficult to be identified by gas chromatography(GC)without standard samples.With the development of modern nuclear magnetic resonance(NMR)techniques,NMR has emerged as a powerful and efficient tool for the rapid analysis of complex and crude mixtures without purification.In this study,the parameters of one-dimensional(1D)total correlation spectroscopy(TOCSY)NMR techniques,including 1D selective gradient TOCSY and 1D chemicalshift-selective filtration(CSSF)with TOCSY,were optimized to obtain comprehensive molecular structure information.The results indicate that the overlapped signals in NMR spectra of nonpolar aromatic compounds(including o-xylene,m-xylene,p-xylene and ethylbenzene),polar aromatic compounds(benzyl alcohol,benzaldehyde,benzoic acid),and aromatic compounds with additional conjugated bonds(styrene)can be resolved in 1D TOCSY.More importantly,full molecular structures can be clearly distinguished by setting appropriate mixing time in 1D TOCSY.This approach simplifies the NMR spectra,provides structural information of entire molecules,and can be applied for the analysis of other structural isomers. 展开更多
关键词 1D TOCSY NMR technologies XYLENES Aromatic compounds Structure information of entire molecular Qualitative analysis
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Bibliometric analysis of phosphoglycerate kinase 1 expression in breast cancer and its distinct upregulation in triple-negative breast cancer
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作者 Jing-Yu Chen Jian-Di Li +3 位作者 Rong-Quan He Zhi-Guang Huang Gang Chen Wen Zou 《World Journal of Clinical Oncology》 2024年第7期867-894,共28页
BACKGROUND Phosphoglycerate kinase 1(PGK1)has been identified as a possible biomarker for breast cancer(BC)and may play a role in the development and advancement of triple-negative BC(TNBC).AIM To explore the PGK1 and... BACKGROUND Phosphoglycerate kinase 1(PGK1)has been identified as a possible biomarker for breast cancer(BC)and may play a role in the development and advancement of triple-negative BC(TNBC).AIM To explore the PGK1 and BC research status and PGK1 expression and mecha-nism differences among TNBC,non-TNBC,and normal breast tissue.METHODS PGK1 and BC related literature was downloaded from Web of Science Core Co-llection Core Collection.Publication counts,key-word frequency,cooperation networks,and theme trends were analyzed.Normal breast,TNBC,and non-TNBC mRNA data were gathered,and differentially expressed genes obtained.Area under the summary receiver operating characteristic curves,sensitivity and specificity of PGK1 expression were determined.Kaplan Meier revealed PGK1’s prognostic implication.PGK1 co-expressed genes were explored,and Gene Onto-logy,Kyoto Encyclopedia of Genes and Genomes,and Disease Ontology applied.Protein-protein interaction networks were constructed.Hub genes identified.RESULTS PGK1 and BC related publications have surged since 2020,with China leading the way.The most frequent keyword was“Expression”.Collaborative networks were found among co-citations,countries,institutions,and authors.PGK1 expression and BC progression were research hotspots,and PGK1 expression and BC survival were research frontiers.In 16 TNBC vs non-cancerous breast and 15 TNBC vs non-TNBC datasets,PGK1 mRNA levels were higher in 1159 TNBC than 1205 non-cancerous breast cases[standardized mean differences(SMD):0.85,95%confidence interval(95%CI):0.54-1.16,I²=86%,P<0.001].PGK1 expression was higher in 1520 TNBC than 7072 non-TNBC cases(SMD:0.25,95%CI:0.03-0.47,I²=91%,P=0.02).Recurrence free survival was lower in PGK1-high-expression than PGK1-low-expression group(hazard ratio:1.282,P=0.023).PGK1 co-expressed genes were concentrated in ATP metabolic process,HIF-1 signaling,and glycolysis/gluconeogenesis pathways.CONCLUSION PGK1 expression is a research hotspot and frontier direction in the BC field.PGK1 may play a strong role in promoting cancer in TNBC by mediating metabolism and HIF-1 signaling pathways. 展开更多
关键词 Phosphoglycerate kinase 1 Breast cancer Triple-negative breast cancer Bibliometric analysis Computational pathology
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Composition Analysis and Identification of Ancient Glass Products Based on L1 Regularization Logistic Regression
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作者 Yuqiao Zhou Xinyang Xu Wenjing Ma 《Applied Mathematics》 2024年第1期51-64,共14页
In view of the composition analysis and identification of ancient glass products, L1 regularization, K-Means cluster analysis, elbow rule and other methods were comprehensively used to build logical regression, cluste... In view of the composition analysis and identification of ancient glass products, L1 regularization, K-Means cluster analysis, elbow rule and other methods were comprehensively used to build logical regression, cluster analysis, hyper-parameter test and other models, and SPSS, Python and other tools were used to obtain the classification rules of glass products under different fluxes, sub classification under different chemical compositions, hyper-parameter K value test and rationality analysis. Research can provide theoretical support for the protection and restoration of ancient glass relics. 展开更多
关键词 Glass Composition L1 Regularization Logistic Regression Model K-Means Clustering analysis Elbow Rule Parameter Verification
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舒肝宁注射液的^(1)H-NMR指纹图谱分析
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作者 何峰 朱彤彤 +4 位作者 韩春月 张昀 杨翠萍 韩立峰 付志飞 《中南药学》 CAS 2024年第3期753-759,共7页
目的对舒肝宁注射液的^(1)H-NMR指纹图谱进行分析,为其质量控制标准技术升级提供参考依据。方法使用Noesygppr1d脉冲序列[recycle delay(RD)-90°-t 1-90°-t_(m)-90°-ACQ]采集1H-NMR谱图,质子共振频率为600.13 MHz,实验... 目的对舒肝宁注射液的^(1)H-NMR指纹图谱进行分析,为其质量控制标准技术升级提供参考依据。方法使用Noesygppr1d脉冲序列[recycle delay(RD)-90°-t 1-90°-t_(m)-90°-ACQ]采集1H-NMR谱图,质子共振频率为600.13 MHz,实验温度为298 K,通过方法学考察验证分析方法可靠性,采用相关系数法和夹角余弦法评价不同批次舒肝宁注射液样品的相似度。结果对舒肝宁注射液的^(1)H-NMR指纹图谱进行分析,共鉴定出88种化学成分,且不同批次的舒肝宁注射液具有较高的相似度。结论建立了一种基于^(1)H-NMR的舒肝宁注射液质量控制方法,可为舒肝宁注射液技术升级提供参考依据。 展开更多
关键词 舒肝宁注射液 1h-nmr 指纹图谱 相似度
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Integration of 1H-NMR-Based Metabolomics Approach with Traditional Chinese Pulse Diagnosis to Evaluate the Qi-Enhancing Activity of Herbal Tea
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作者 Chia-Hsin Lin Po-Jung Huang +2 位作者 Chung-Hsuan Wang Mo-Rong Xu Sheng-Yang Wang 《Chinese Medicine》 CAS 2024年第3期49-74,共26页
Human metabolism is intricately linked to an individual’s health status. Regardless of living habits, it will be reflected in the metabolic characteristics of urine. The utilization of the 1H NMR-based metabolomics m... Human metabolism is intricately linked to an individual’s health status. Regardless of living habits, it will be reflected in the metabolic characteristics of urine. The utilization of the 1H NMR-based metabolomics method has enabled examine the metabolomic changes in urine under various physiology conditions, providing valuable insights into metabolites. In this particular study, volunteers were divided into two groups based on the strength of their spleen pulses, using the pulse diagnosis method employed in traditional Chinese medicine. Subsequently, their urine samples were analyzed, revealing notable variances in urea, creatinine, citric acid, succinic acid, trimethylamine-N-oxide (TMAO), alanine, hippuric acid, and glycine between the two groups. Interestingly, individuals with weak spleen pulses showed significant improvements after consuming herbal tea. Furthermore, we conducted LC-MS analysis on herbal tea and performed adenosine triphosphate (ATP) activity tests on the C2C12 mouse skeletal muscle cell line. The results indicated that within a reasonable concentration range, exposure to herbal tea led to an increase in the mitochondrial ATP production capacity of C2C12 cells. These findings shed light on the relationship between traditional Chinese medicine pulse diagnosis and urine metabolites, highlighting their potential as non-invasive and straightforward health assessment indicators. They can aid in the preliminary determination of necessary dietary and lifestyle changes to enhance overall bodily health. 展开更多
关键词 1h-nmr Metabolomics Traditional Chinese Pulse Diagnosis Qi-Enhancing Herbal Tea
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Carbon Chain Length Determines Inhibitory Potency of Perfluoroalkyl Sulfonic Acids on Human Placental 3β-Hydroxysteroid Dehydrogenase 1:Screening,Structure-Activity Relationship,and In Silico Analysis
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作者 TANG Lu Ming MAO Bai Ping +4 位作者 ZHANG Bing Ru LI Jing Jing TANG Yun Bing LI Hui Tao GE Ren Shan 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2023年第11期1015-1027,共13页
Objective This study aimed to compare 9 perfluoroalkyl sulfonic acids(PFSA)with carbon chain lengths(C4–C12)to inhibit human placental 3β-hydroxysteroid dehydrogenase 1(3β-HSD1),aromatase,and rat 3β-HSD4 activitie... Objective This study aimed to compare 9 perfluoroalkyl sulfonic acids(PFSA)with carbon chain lengths(C4–C12)to inhibit human placental 3β-hydroxysteroid dehydrogenase 1(3β-HSD1),aromatase,and rat 3β-HSD4 activities.Methods Human and rat placental 3β-HSDs activities were determined by converting pregnenolone to progesterone and progesterone secretion in JEG-3 cells was determined using HPLC/MS–MS,and human aromatase activity was determined by radioimmunoassay.Results PFSA inhibited human 3β-HSD1 structure-dependently in the order:perfluorooctanesulfonic acid(PFOS,half-maximum inhibitory concentration,IC50:9.03±4.83μmol/L)>perfluorodecanesulfonic acid(PFDS,42.52±8.99μmol/L)>perfluoroheptanesulfonic acid(PFHpS,112.6±29.39μmol/L)>perfluorobutanesulfonic acid(PFBS)=perfluoropentanesulfonic acid(PFPS)=perfluorohexanesulfonic acid(PFHxS)=perfluorododecanesulfonic acid(PFDoS)(ineffective at 100μmol/L).6:2FTS(1H,1H,2H,2H-perfluorooctanesulfonic acid)and 8:2FTS(1H,1H,2H,2H-perfluorodecanesulfonic acid)did not inhibit human 3β-HSD1.PFOS and PFHpS are mixed inhibitors,whereas PFDS is a competitive inhibitor.Moreover,1–10μmol/L PFOS and PFDS significantly reduced progesterone biosynthesis in JEG-3 cells.Docking analysis revealed that PFSA binds to the steroid-binding site of human 3β-HSD1 in a carbon chain length-dependent manner.All 100μmol/L PFSA solutions did not affect rat 3β-HSD4 and human placental aromatase activity.Conclusion Carbon chain length determines inhibitory potency of PFSA on human placental 3β-HSD1 in a V-shaped transition at PFOS(C8),with inhibitory potency of PFOS>PFDS>PFHpS>PFBS=PFPS=PFHxS=PFDoS=6:2FTS=8:2FTS. 展开更多
关键词 3β-hydroxysteroid dehydrogenase 1 Docking analysis Perfluorooctanesulfonic acid PROGESTERONE STRUCTURE-ACTIVITYRELATIONSHIP
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The diagnostic value of the expression of the thymidine kinase 1 in lung cancer:A meta analysis
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作者 HU Chan LI Jing‑cheng +2 位作者 LIU Ling PENG Qian SANG Sheng‑gang 《Journal of Hainan Medical University》 CAS 2023年第11期48-56,共9页
Objective:To study is to evaluate the diagnostic value of the expression of thymidine kinase 1(TK1)in lung cancer through literature review and meta-analysis.Methods:Firstly,we searched Pubmed,Embase,Cochrane,Web of S... Objective:To study is to evaluate the diagnostic value of the expression of thymidine kinase 1(TK1)in lung cancer through literature review and meta-analysis.Methods:Firstly,we searched Pubmed,Embase,Cochrane,Web of Science,CBM,CNKI,Wanfang and other databases up to June 2022.Then two researchers separately selected the clinical study on diagnosis of lung cancer by the expression of the TK1 and treatment and obtained the full text of the literature.Then we evaluated the systematic quality and bias risk of the included literatures by using Revman 5.3 software,and the consistency among the covariables in meta analysis.Finally,the Sensitivity(Sen),the Specificity(Spe)and other indicators were analyzed by using Stata16.0 software.Results:The study included 37 literatures,including 3218 lung cancer cases and 2976 control cases.The meta-analysis showed that the Ser and Spe of the expression of the TK1 in the diagnosis of lung cancer were 0.63(95%CI:0.57,0.68)and 0.88(95%CI:0.84,0.91),while positive likelihood ratio(PLR)was 5.34(95%CI:4.02,7.1)and negative likelihood ratio(NLR)was 0.42(95%CI:0.37,0.48),diagnostic odd sratio(DOR)was 12.69(95%CI:8.91,18.08),and the area under the ROC curve(AUC)was 0.82(95%CI:0.79,0.85).When TK1,CEA and CYFRA21-1 were used as combined diagnostic indexes of lung cancer,Sen was 0.82(95%CI:0.76,0.86),Spe 0.78(95%CI:0.46,0.94),PLR 3.69(95%CI:1.28,10.66),NLR 0.24(95%CI:0.18,0.31),DOR 15.59(95%CI:4.56,53.36),AUC 0.84(95%CI:0.80,0.87).The Youden index of combined diagnosis was 0.60,which was higher than that of TK1 alone.Conclusion:TK1 alone as a diagnostic index of lung cancer has low Sen,but its Sep is higher.So it has a certain diagnostic value.TK1 combined with CEA and CYFRA21-1 has higher Sen in the diagnosis of lung cancer,and the diagnostic value is better. 展开更多
关键词 TK1 Lung cancer Diagnostic value Meta analysis
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A Comparative Analysis of the New -3(-n) - 1 Remer Conjecture and a Proof of the 3n + 1 Collatz Conjecture
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作者 Mike Remer 《Journal of Applied Mathematics and Physics》 2023年第8期2216-2220,共5页
This scientific paper is a comparative analysis of two mathematical conjectures. The newly proposed -3(-n) - 1 Remer conjecture and how it is related to and a proof of the more well known 3n + 1 Collatz conjecture. An... This scientific paper is a comparative analysis of two mathematical conjectures. The newly proposed -3(-n) - 1 Remer conjecture and how it is related to and a proof of the more well known 3n + 1 Collatz conjecture. An overview of both conjectures and their respective iterative processes will be presented. Showcasing their unique properties and behavior to each other. Through a detailed comparison, we highlight the similarities and differences between these two conjectures and discuss their significance in the field of mathematics. And how they prove each other to be true. 展开更多
关键词 -3(-n) - 1 Remer Conjecture 3n + 1 Collatz Conjecture Comparative analysis PROOF Natural Numbers Integer Sequences Factorial Processes Par-tial Differential Equations Bounded Values Collatz Conjecture Collatz Algo-rithm Collatz Operator Collatz Compliance And Mathematical Conjectures
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Correlation and Path Analysis for Growth Traits in F_1 Population of Pearl Oyster Pinctada martensii 被引量:34
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作者 邓岳文 杜晓东 +2 位作者 王庆恒 符韶 黄荣莲 《Marine Science Bulletin》 CAS 2008年第2期68-73,共6页
120 pearl oysters (Pinctada martensii) were randomly sampled from F1 population, and shell length, shell width, shell height, shell weight and total weight of each sample were measured. Correlation and path analysis... 120 pearl oysters (Pinctada martensii) were randomly sampled from F1 population, and shell length, shell width, shell height, shell weight and total weight of each sample were measured. Correlation and path analysis were conducted on the basis of measurement data. The results showed that shell length, shell width, shell height, shell weight and total weight were significantly correlated (P 〈 0.05). Total weight was significantly and positively correlated with shell weight (r = 0.8970), shell height (r = 0.6974), shell width (r = 0.6521) and shell length (r = 0.5486). Shell weight, shell height, shell width and shell length had positive and direct effects on total wet weight, with the values of 0.6356, 0.1872, 0.1814 and 0.0599, respectively. The results indicated that growth traits (shell length, shell width, shell height, shell weight and total wet weigh) of the F1 population could be improved by direct or indirect selection. 展开更多
关键词 Pinctada martensii selected line F1 growth traits CORRELATION path analysis
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Cloning,Identification and Differential Expression Analysis of Full-length cDNA of Carp Interleukin-1β
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作者 何江帅 卢强 +3 位作者 李伟 赵晓 冯祥汝 陈义龙 《Agricultural Science & Technology》 CAS 2011年第3期405-408,412,共5页
[Objective] The research aimed to carry out the cloning,identification and differential expression analysis of carp interleukin-1β (IL-1β) cDNA. [Method] By using DD-RTPCR method,the differential expression cDNA f... [Objective] The research aimed to carry out the cloning,identification and differential expression analysis of carp interleukin-1β (IL-1β) cDNA. [Method] By using DD-RTPCR method,the differential expression cDNA fragments were gained. The cDNA library of carp peripheral blood leucocytes which was stimulated by the mitogen was screened,and the full length cDNA of carp IL-1β was cloned. Moreover,the sequence analysis and differential expression analysis were carried out. [Result] The positive clone which had a whole ORF that encoded 276 amino acids was obtained. The cluster analysis showed that the amino acid sequence of carp IL-1β and Japanese carp closely gathered as a branch,and the homoeology of amino acid sequence reached 95%. The clustering order was the carassius,zebra fish,pig,cattle,horse,human and mouse in turn. The differential expression analysis showed that the expression of IL-1β in the leucocytes significantly increased in the prior period (4 h) after the mitogen stimulated. But as the time went by (12 and 24 h),it didn't increase in the same period. The total trend of expression amount presented the peak type. [Conclusion] The research laid the foundation for further studying the expression manner,function characteristic,regulation mechanism of IL-1β in vivo and its action mechanisms in the inflammatory reaction,emergency reaction and immune response. 展开更多
关键词 CARP INTERLEUKIN-1Β cDNA cloning IDENTIFICATION Differential expression analysis
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Cloning and Sequence Analysis on IGF-1 Gene of Hubei White Swine
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作者 乔宪凤 张立苹 +6 位作者 毕延震 刘西梅 华文君 华再东 肖红卫 周荆荣 郑新民 《Agricultural Science & Technology》 CAS 2011年第11期1569-1571,1593,共4页
[Objective] The study aimed at cloning and analyzing the insulin-like growth factor-1 (IGF-1) gene from liver of Hubei white swine. [Method] The total RNA was extracted by using Trizol from the liver of Hubei white ... [Objective] The study aimed at cloning and analyzing the insulin-like growth factor-1 (IGF-1) gene from liver of Hubei white swine. [Method] The total RNA was extracted by using Trizol from the liver of Hubei white swine and used as template to amplify IGF-1 gene cDNA by RT-PCR. The cDNA product was cloned into pCRII vector, screened with blue-white colonies, digested with double enzymes and sequenced. [Result] The sequencing result indicated that the IGF-1 gene consisted of 607 nucleotides, containing 5'-untranslated region at nucleotides 1-145, a complete ORF at nucleotides 146-538 encoding 130 amino acids, and 3'-untranslated region at nucleotides 539-607. It shared 100% homology with the porcine IGF-1 gene reported by Muller et al. [Conclusion] The successful cloning and sequencing of the Hubei white swine IGF-1 gene confirmed that IGF-I gene was highly conserved, which provided technical basis for the use of transgenic technology for breeding of Hubei white swine. 展开更多
关键词 Hubei white swine IGF-1 gene Sequence analysis
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Comparative Analysis of Improving Effects of 12 Maize Populations with Improved S_1 Selection Method
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作者 孙峰成 冯勇 +6 位作者 付增娟 苏二虎 张来厚 赵瑞霞 刘志雄 石海波 李美娜 《Agricultural Science & Technology》 CAS 2014年第10期1687-1692,1713,共7页
ln this study, 12 maize populations were improved with the improved S1 selection method, aiming to increase the improvement efficiency of maize popula-tions. The results showed that number of rows per spike, number of... ln this study, 12 maize populations were improved with the improved S1 selection method, aiming to increase the improvement efficiency of maize popula-tions. The results showed that number of rows per spike, number of grains per row and 100-grain weight were the three important component traits of maize yield. The highest genetic increment was found in Mengqun 2, fol owed by Mengqun 4, Mengqun 1 and other 7 maize populations. Negative genetic increment was shown in Mengqun 3 and 3 introduced foreign maize populations. Some changes were shown in spikes, plant traits and genetic diversity of maize populations. Based on our results, we concluded that Mengqun 2, Mengqun 4, Zhongzong 7, Mengqun C and Mengqun A could be directly used for the line breeding by selfing for their higher genetic increment of yield and better improvement effects of other agricultural traits. Compared with these 5 populations, the improvement potential of other maize populations was limited for their lower genetic increment. 展开更多
关键词 lmproved S1 selection method Maize population Genetic gain Comparative analysis
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Cloning and Phylogenetic Analysis of NS1 Genes from Different Isolates of H9N2 Subtype Duck Influenza Virus
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作者 谢青梅 张祥斌 +3 位作者 吴志强 冀君 周科 毕英佐 《Agricultural Science & Technology》 CAS 2009年第1期64-67,126,共5页
[ Objective] The study aimed to lay a foundation for the further studies on function mechanism of NS1 protein in the interspecies transmission of waterfowl influenza virus. [Method] Using the serologic assay and the s... [ Objective] The study aimed to lay a foundation for the further studies on function mechanism of NS1 protein in the interspecies transmission of waterfowl influenza virus. [Method] Using the serologic assay and the specific RT-PCR method, some strains of H9 subtype waterfowl influenza virus were isolated from the 12 to 20 day-old muscovy duck flocks without any clinical symptoms in different areas of Guangdong Province. Four of these strains, including A/duck/ZQ/303/2007(H9N2) (A3 for short), A/Duck/FJ/301/2007 (H9N2) (C1 for short), A/Duck/NH/306/2007(H9N2) ( D6 for short), A/duck/SS/402/2007(H9N2) ( E2 for short), and a strain named A/duck/ZC/2007(H9N2) (L1 for short) from a muscovy duck died of avian influenza virus (AIV), were used for NSl gene cloning and sequencing. Subsequently, the obtained NSl gene sequences were compared with other NS1 sequences registered in GenBank, and the phylogenetic analysis was also conducted. [Result] When compared with the H9N2 AIV NS1 sequences in GenBank, the NSl genes of the four AIV strains A3, C1, 136 and E2 displayed homologies ranging from 99% to 100% at nucleotide level, and 95% to 100% at amino acid level; while the NSl gene of L1 strain displayed homology ranging from 94% to 97% at nucleotide level, and 93% to 98% at amino acid level. The phylogenetic tree demonstrated that A3, C1, D6 and E2 were highly resemblant, and L1 was closest to AY66473 (chicken, 2003). By comparison with the NS1 gene sequences of L1, AF523514 (duck), AY664743 (chicken) and EF155262.1 (quail) using DNAstar, A3, C1, D6 and E.2 presented nucleotide variations at site 21 ( R→Q), 70, 71 ( KE→EG), 86 ( A→S), 124 (V→M) and 225 ( S→N), and amino acid variations at site 21,70, 71 and 86 in dsRNA- dependent protein kinase (PKR) binding domain of NSl gene, which induced the evident variations of antigenic determinant and surface proba- bility plot of NS1 protein. [ Conclusion] This study suggested that the amino acid sequence variation in PKR binding domain of NS1 protein had something to do with the virus pathogenicity. 展开更多
关键词 H9N2 subtype Duck influenza virus NS1 gene PKR Phylogenetic analysis
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2021-2022年河南省猪细小病毒1~7型检测与分析
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作者 郭全海 许夕雅 +4 位作者 石蒙蒙 杨寒 高冬生 王永生 陈陆 《动物医学进展》 北大核心 2024年第6期123-129,共7页
旨在了解猪细小病毒1~7型(PPV1~PPV7)在河南省的流行情况。利用PCR检测了2021-2022年河南省猪场送检的748份样品,并对检测数据进行了分析。结果表明,PPV1/2/3/5/6/7在河南省各地区一年四季广泛流行,而秋、冬季节是感染高峰期,PPV2(16.0... 旨在了解猪细小病毒1~7型(PPV1~PPV7)在河南省的流行情况。利用PCR检测了2021-2022年河南省猪场送检的748份样品,并对检测数据进行了分析。结果表明,PPV1/2/3/5/6/7在河南省各地区一年四季广泛流行,而秋、冬季节是感染高峰期,PPV2(16.04%)的感染率最高,PPV7(15.11%)次之。产房仔猪未检出PPV1/3/5,PPV2/6/7在各生长阶段猪群中均有检出,患呼吸系统疾病的保育和育肥猪中PPV各型检出率均较高,尤以PPV2常见。PPV2和PPV7在口腔液、血样、肺脾淋巴结中检出率均较高,血样中较低,PPV3常存在于血清和组织中,PPV5多见于口腔液,PPV6多见于血样。研究证实,除PPV4未检出外,其他6种PPV在河南均存在,并且多与其他病原混合感染,PPV2、PPV7可与多种病原混合感染,PPV7与PCV2混合感染最常见。 展开更多
关键词 猪细小病毒1~7型 检测 分析
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北京再发黑热病利什曼原虫K26基因和ITS-1序列的多态性分析
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作者 孙玉兰 王小梅 +2 位作者 吴文婷 张代涛 何战英 《寄生虫与医学昆虫学报》 CAS 2024年第1期1-5,52,共6页
目的了解北京市再发黑热病病例的病原分子遗传背景。方法使用PCR方法分别扩增其亲水性酰化表面蛋白B(K26)和核糖体DNA内转录间隔区Ⅰ(ITS-1),然后克隆测序,分析其多态性,构建系统发育树以确定患者感染原虫的虫种类型及其遗传关系。结果... 目的了解北京市再发黑热病病例的病原分子遗传背景。方法使用PCR方法分别扩增其亲水性酰化表面蛋白B(K26)和核糖体DNA内转录间隔区Ⅰ(ITS-1),然后克隆测序,分析其多态性,构建系统发育树以确定患者感染原虫的虫种类型及其遗传关系。结果K26基因扩增出626 bp大小片段,其长度与国内流行株差异明显,其氨基酸序列由14个氨基酸的基序重复排列组成,但个别位置发生氨基酸替代。K26序列的系统进化树分析显示,北京病例虫株与法国和西班牙的婴儿利什曼原虫相近,但与国内新疆、四川、河北等地的婴儿利什曼原虫虫株距离较远;ITS-1序列扩增出314 bp大小的片段,其系统发育分析显示与婴儿利什曼原虫Leishmania infantum属于同一分支。结论该病例感染的为婴儿利什曼原虫L.infantum,且与国内其他流行区的虫株有一定差异。 展开更多
关键词 黑热病 婴儿利什曼原虫 多态性 K26 ITS-1 北京
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以“维生素B_(1)质量分析”为例探索药物分析实验教学改革
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作者 李婷婷 廖丽云 +2 位作者 代晶 巫传玲 邓晶晶 《广东化工》 CAS 2024年第18期222-224,共3页
以药物分析综合性实验《维生素B_(1)原料药及片剂的质量研究》为例,将新教学模式应用于药物分析综合实验项目,参照药物质量控制研究岗位的工作特点把项目培养方案与该岗位的职业需求相对接,设置岗位情景、明确岗位目标、增加岗位实例。... 以药物分析综合性实验《维生素B_(1)原料药及片剂的质量研究》为例,将新教学模式应用于药物分析综合实验项目,参照药物质量控制研究岗位的工作特点把项目培养方案与该岗位的职业需求相对接,设置岗位情景、明确岗位目标、增加岗位实例。最终提高学生的岗位适应能力和职业技能。以此,培养具备专业基础扎实、严格控制药品质量、具有良好药学职业道德的综合型药学人才。 展开更多
关键词 维生素B_(1) 质量分析 药物分析实验 综合型药学人才
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Effect of microwave-assisted acidification on the microstructure of coal:XRD,^(1)H-NMR, and SEM studies 被引量:3
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作者 He Li Wuche Liu +5 位作者 Jiexin Lu Yi Lu Shiliang Shi Zheng Wang Qing Ye Zhenzhen Jia 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第7期919-926,共8页
Microwave heating contributes to coal fracturing and gas desorption. However, problems of low penetration depth, local overheating and fracture closure exist. Coal demineralisation by acids has advantages in coal unbl... Microwave heating contributes to coal fracturing and gas desorption. However, problems of low penetration depth, local overheating and fracture closure exist. Coal demineralisation by acids has advantages in coal unblocking and permeability improvement, while it is difficult for acid to enter microcracks.Microwave-asisted acidification may offer an alternative. In this work, XRD,^(1)H-NMR, and SEM were used to evaluate the effect of microwave-assisted acidification on the microstructure of coal. Results show that kaolinite, calcite, and dolomite can be dissolved by acid. After microwave irradiation, the graphitization of microcrystalline structure of carbon improves. Microwave-assisted acidification erodes minerals in coal and enhances the graphitization degree of microcrystalline structure. Compared to individual microwave irradiation or acidification, the pore volume and pore connectivity can be greatly enhanced by microwave-assisted acidification. The NMR permeability of coal increased by 28.05%. This study demonstrates the potential of microwave-assisted acidification for coalbed methane recovery. 展开更多
关键词 Microwave-assisted acidification MICROSTRUCTURE XRD ^(1)h-nmr SEM
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鉴定LTBP1作为胃癌预后的生物标志物及其与肿瘤免疫微环境的相关性
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作者 王小瑞 王觅柱 《医学分子生物学杂志》 CAS 2024年第1期57-62,共6页
目的探索潜在转化生长因子β结合蛋白1(latent transforming growth factor beta binding protein 1,LTBP1)在胃癌发生发展及免疫微环境中的生物学功能。方法在TCGA数据库中分析LTBP1在泛癌中的表达,然后通过胃癌组织和癌旁组织进行验... 目的探索潜在转化生长因子β结合蛋白1(latent transforming growth factor beta binding protein 1,LTBP1)在胃癌发生发展及免疫微环境中的生物学功能。方法在TCGA数据库中分析LTBP1在泛癌中的表达,然后通过胃癌组织和癌旁组织进行验证。通过回归比例分析法分析LTBP1表达与临床病理变量之间的相关性。Cox回归分析和Kaplan-Meier图用于评估LTBP1在胃癌中的预后价值。通过TIMER分析LTBP1的表达水平与胃癌中免疫细胞浸润之间的相关性。免疫组织化学染色检测LTBP1蛋白在胃癌组织及癌旁组织中的表达水平。结果与正常胃组织相比,胃癌组织中LTBP1表达显著上调。其表达与病理TNM分期显著相关。LTBP1高表达的胃癌患者的总体生存率(overall survival,OS)缩短。免疫组化结果显示,与癌旁组织相比,LTBP1在胃癌组织中显著高表达。TIMER检测发现LTBP1的表达与3种免疫细胞浸润呈正相关。结论LTBP1可能是胃癌预后的一个潜在生物标志物,并影响癌症的肿瘤免疫微环境。 展开更多
关键词 胃癌 潜在转化生长因子β结合蛋白1 生存分析 肿瘤微环境
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胸腺肽α_(1)预防慢性阻塞性肺疾病稳定期急性加重的有效性及安全性Meta分析
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作者 肖敏 姜怡雯 钟燕 《中国药业》 CAS 2024年第13期115-120,共6页
目的系统评价胸腺肽α_(1)预防慢性阻塞性肺疾病(COPD)稳定期(SPCOPD)急性加重的有效性及安全性。方法采用计算机检索PubMed,Embase,Medline,The Cochrane Library及中国生物医学文献数据库(CBM)、中国知网(CNKI)、万方(WanFang)、维普(... 目的系统评价胸腺肽α_(1)预防慢性阻塞性肺疾病(COPD)稳定期(SPCOPD)急性加重的有效性及安全性。方法采用计算机检索PubMed,Embase,Medline,The Cochrane Library及中国生物医学文献数据库(CBM)、中国知网(CNKI)、万方(WanFang)、维普(VIP)数据库中胸腺肽α_(1)治疗SPCOPD的随机对照试验(RCT),检索时限为自建库起至2022年12月。参考Cochrane 2.0风险偏倚评估工具对文献进行偏倚风险评估,采用RevMan 5.3软件进行Meta分析。结果最终纳入10项RCT,涉及811例患者。Meta分析结果显示,有效性方面,胸腺肽α_(1)可减少SPCOPD患者的急性加重次数[MD=-0.96,95%CI(-1.59,-0.32),P=0.003]和急性加重天数[MD=-9.14,95%CI(-11.71,-6.56),P<0.00001],改善第1秒用力呼气容积[MD=0.12,95%CI(0.00,0.24),P=0.04],调节T淋巴细胞亚群CD[4 MD=6.66,95%CI(4.39,8.93),P<0.00001],CD[8 MD=-6.00,95%CI(-8.96,-3.04),P<0.0001],CD_(4)/CD_(8)[MD=0.61,95%CI(0.39,0.84),P<0.00001];安全性方面,仅少数患者有轻度恶心、口干、咽部不适等不良反应,可自行缓解。结论胸腺肽α_(1)预防SPCOPD急性加重的有效性和安全性均良好。 展开更多
关键词 胸腺肽α_(1) 慢性阻塞性肺疾病稳定期 急性加重 有效性 安全性 META分析
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