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复方醋酸钠林格注射液中无水葡萄糖含量测定方法的建立及葡萄糖转化现象的探讨
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作者 章娟 石颖 +1 位作者 邱娟 李玮玲 《广东药科大学学报》 CAS 2023年第4期14-19,共6页
目的建立复方醋酸钠林格注射液中无水葡萄糖含量测定方法,并针对方法建立中发现的葡萄糖转化问题开展研究。方法采用氨基硅烷键合硅胶为填充剂的色谱柱;以乙腈-水-氨水(体积比75∶25∶0.1)为流动相;示差折光检测器检测;流速为1.0 mL/min... 目的建立复方醋酸钠林格注射液中无水葡萄糖含量测定方法,并针对方法建立中发现的葡萄糖转化问题开展研究。方法采用氨基硅烷键合硅胶为填充剂的色谱柱;以乙腈-水-氨水(体积比75∶25∶0.1)为流动相;示差折光检测器检测;流速为1.0 mL/min,柱温和检测池温度均为40℃。结果无水葡萄糖浓度在0.4125~8.249 mg/mL范围内线性关系良好(r=1.0000),定量限为101μg/L,平均回收率为100.5%,RSD为0.5%,采用该测定法发现样品中少量葡萄糖转化为果糖。结论建立的方法简单、准确、灵敏度高,不受葡萄糖转化现象的干扰,适用于复方醋酸钠林格注射液中无水葡萄糖的含量测定。 展开更多
关键词 复方醋酸钠林格注射液 无水葡萄糖 葡萄糖
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论信托对现物出资财产所有权转移的保护 被引量:1
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作者 孙学亮 李劼 《天津商业大学学报》 2010年第3期60-64,共5页
在公司设立中,现物出资是与现金出资相对应的一种出资方式。我国《公司法》及《公司登记管理条例》对于现物出资财产所有权转移的规定与传统民事主体理论的冲突,使得现物出资财产所有权移转的实际操作陷入了困境。通过对国内外立法例的... 在公司设立中,现物出资是与现金出资相对应的一种出资方式。我国《公司法》及《公司登记管理条例》对于现物出资财产所有权转移的规定与传统民事主体理论的冲突,使得现物出资财产所有权移转的实际操作陷入了困境。通过对国内外立法例的比较研究,将现物出资财产所有权进行信托,以现物出资财产的独立性公示来明确现物出资的目的及其中的法律关系,利于解决现实存在的问题。 展开更多
关键词 物出资所有权移 公示公信 信托
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Cavitary Pulmonary Metastases: CT Features and Their Correlation with the Pathology of the Primary Malignancy 被引量:1
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作者 于小平 王平 梁赵玉 《The Chinese-German Journal of Clinical Oncology》 CAS 2004年第1期29-33,66,共6页
Objective: To study CT features of cavitary pulmonary metastases and to investigate the pos- sible relationship between CT features and the pathology of the primary lesions. Methods: CT ?ndings o... Objective: To study CT features of cavitary pulmonary metastases and to investigate the pos- sible relationship between CT features and the pathology of the primary lesions. Methods: CT ?ndings of 131 cavitary metastatic nodules in 40 patients with pathologically-proved pulmonary metastases were retrospectively analyzed. A comparison between CT signs and the pathologic types of the primary tumors was made. Results: Cavitary metastases and multiple solid nodules coexisted in all patients. Cavitary metastases presented as bubble (n=41), irregular (n=33), cystic (n=26) or small circular (n=31) cavities, with even (n=61) or uneven (n=70) thickness of the cavity wall. Of 131 cavitary nodules, diameter less than 15 mm was seen in 44, between 15–25 mm in 66, 25–40 mm in 17 and larger than 40 mm in 4 respectively. And the wall thickness of the cavity below 4 mm, between 4–15 mm and over 15 mm was respectively seen in 69, 44 and 18 metastatic nodules. Cavitary pulmonary metastases mainly occurred in patients whose primary malignancy was squamous cell carcinoma (n=13) or adenocarcinoma (n=22). Both squamous cell carcinoma and adenocarcinoma had its own CT characteristics. The occurrence of cavity bore no relationship to its site in the lung. Conclusion: Cavitary pulmonary metastases carries certain CT features and its occurrence is related to the pathologic type of the primary malignancy. 展开更多
关键词 lung neoplasm metastatic tomography X-ray computed PATHOLOGY
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农业部制定“十三五”农业农村经济发展规划
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《现代畜牧兽医》 2015年第3期58-59,共2页
农业部召开“十三五”农业农村经济发展规划编制专题部署会.安排“十三五”规划编制工作。农业部副部长余欣荣指出,编制好“十三五”农业农村经济规划要坚持正确导向。既要立足当前,也要着眼长远;既要立足农业,又要跳出农业看农业... 农业部召开“十三五”农业农村经济发展规划编制专题部署会.安排“十三五”规划编制工作。农业部副部长余欣荣指出,编制好“十三五”农业农村经济规划要坚持正确导向。既要立足当前,也要着眼长远;既要立足农业,又要跳出农业看农业;既要立足国内,也要放眼世界。具体而言,要坚持五大导向:一是坚持战略导向,把中央对“三农”工作的重要战略部署贯穿于规划编制的全过程。 展开更多
关键词 农业部 中国 农村经济 发展现转
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Comparative Study of CT Images of Cerebral Metastasis from Pulmonary Squamous Cell Carcinoma and Adenocarcinoma
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作者 高德培 丁莹莹 谭静 《The Chinese-German Journal of Clinical Oncology》 CAS 2004年第1期34-36,66,共4页
Objective: To explore the di?erence of CT images of metastatic tumors to the brain of lung squamous cell cancer and lung glandular cancer. Methods: Forty-?ve cases of lung squamous cell cancer an... Objective: To explore the di?erence of CT images of metastatic tumors to the brain of lung squamous cell cancer and lung glandular cancer. Methods: Forty-?ve cases of lung squamous cell cancer and 59 cases of lung glandular cancer have gone through pathological con?rmation and all the 104 cases have been put under enhanced scanning on the basis of ?at scanning. The shape and density of the metastatic tumors, encephaledema around the tumors, and the reinforcement change after the enhancement were analyzed. Results: The CT scanning images of all the cases showed that, under ?at scanning, the density of the metastatic tumors to the brain of lung squamous cell cancer was over the slightly-high level and by no means even. Again, under ?at scanning, some 10 cases of metastatic tumors to the brain of lung glandular cancer showed a slightly-high density and some 49 other cases a low density and sack-like low density. Forty-?ve cases of metastatic tumors to the brain of lung squamous cell cancer were with hydroncus while some 30 cases of that of lung glandular cancer were in the same condition. Most of the two types of metastatic tumors, amounting to 97 cases, took place in supratentorial manner, and only 7 cases took place in subtentorial manner. Conclusion: The CT images of metastatic tumors to the brain of lung squamous cell cancer and lung glandular cancer are obviously di?erent from each other. As for the lung squamous cell cancer, the ?at scanning density of the tumor is over the slightly-high level with unevenness. There is relatively obvious reinforcement and obvious hydroncus. As for the lung glandular cancer, the metastatic tumor to the brain shows a low density and sack-like low density under ?at scanning. There is no obvious reinforcement and relatively slight hydroncus. 展开更多
关键词 tumor lung metastatic tumor brain tomography X-ray computer
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INFLUENCE OF VIRTUAL PHOTON FIELD ON COLLAPSE AND REVIVAL PHENOMENON IN TWO PHOTON J C MODEL WITHOUT RWA
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作者 杨雁南 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1999年第1期86-92,共7页
The time evolution of system in two photon Jaynes Cummings (J C) model without rotating waves approximation (RWA) is obtained by using the theory of ordinary differential equations. Based on the evolution, the mean ... The time evolution of system in two photon Jaynes Cummings (J C) model without rotating waves approximation (RWA) is obtained by using the theory of ordinary differential equations. Based on the evolution, the mean value of the atom inversion operator 〈 S 3(t)〉 is gi ven. The influence of the “counter rotating term” on the collapse and revival phenomenon is discussed from the comparison between the cases with RWA and without RWA. It shows that the influence of the virtual photon field makes the quantum fluctuations appear on the collapse and revival phenomenon. 展开更多
关键词 PHOTONS quantum noise J C model rotating waves approximation collapse and revival phenomenon atom inversion operator
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转体式现浇箱梁桥满堂支架受力分析研究 被引量:3
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作者 冉涛 张玲 +4 位作者 李永超 黄和江 蒋林珊 刘建彪 杨俊毅 《公路交通科技(应用技术版)》 CSCD 北大核心 2020年第4期225-228,共4页
通常现浇箱梁满堂支架受力采用上部荷载一次性施加的方法计算,在混凝土浇筑完成后支架杆件受力达到峰值,但部分工程中满堂支架实际受力情况与依据规范公式计算结果存在一定差异,支架设计存在安全隐患。本文以武易高速公路马官营大桥主... 通常现浇箱梁满堂支架受力采用上部荷载一次性施加的方法计算,在混凝土浇筑完成后支架杆件受力达到峰值,但部分工程中满堂支架实际受力情况与依据规范公式计算结果存在一定差异,支架设计存在安全隐患。本文以武易高速公路马官营大桥主跨转体式现浇箱梁桥满堂支架为例,发现在箱梁浇筑完成15h后支架杆件的受力达到峰值,且伴随立杆弯曲和垫木被压缩现象,针对这一现象进行分析研究,以期揭示安全隐患产生的原因,并提出建议措施。 展开更多
关键词 体式浇箱梁 满堂支架 受力分析 监测
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Novel insight into mechanisms of cholestatic liver injury 被引量:26
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作者 Benjamin L Woolbright Hartmut Jaeschke 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第36期4985-4993,共9页
Cholestasis results in a buildup of bile acids in serum and in hepatocytes.Early studies into the mechanisms of cholestatic liver injury strongly implicated bile acidinduced apoptosis as the major cause of hepatocellu... Cholestasis results in a buildup of bile acids in serum and in hepatocytes.Early studies into the mechanisms of cholestatic liver injury strongly implicated bile acidinduced apoptosis as the major cause of hepatocellular injury.Recent work has focused both on the role of bile acids in cell signaling as well as the role of sterile inflammation in the pathophysiology.Advances in modern analytical methodology have allowed for more accurate measuring of bile acid concentrations in serum,liver,and bile to very low levels of detection.Interestingly,toxic bile acid levels are seemingly far lower than previously hypothesized.The initial hypothesis has been based largely upon the exposure of μmol/L concentrations of toxic bile acids and bile salts to primary hepatocytes in cell culture,the possibility that in vivo bile acid concentrations may be far lower than the observed in vitro toxicity has far reaching implications in the mechanism of injury.This review will focus on both how different bile acids and different bile acid concentrations can affect hepatocytes during cholestasis,and additionally provide insight into how these data support recent hypotheses that cholestatic liver injury may not occur through direct bile acid-induced apoptosis,but may involve largely inflammatory cell-mediated liver cell necrosis. 展开更多
关键词 Bile acids CHOLESTASIS APOPTOSIS Necro-sis NEUTROPHILS Innate immunity Bile duct ligation
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Animal Idioms' Teaching in Cognitive Perspective——from the Contrastive Analysis on Chinese "Hu" Idioms and English "Lion" Idioms
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作者 周红 《Sino-US English Teaching》 2007年第1期18-23,共6页
In the actual idioms teaching, most students feel that idioms are difficult to comprehend, memorize and make actual application just because the overall meanings of idioms are unpredictable. Since cognitive linguistic... In the actual idioms teaching, most students feel that idioms are difficult to comprehend, memorize and make actual application just because the overall meanings of idioms are unpredictable. Since cognitive linguistics is based on embodiment, it can change the abstract things into comparatively concrete things, which provides a shortest way to grasp these idioms. Actually, most idioms are based on conceptual metaphor and metonymy composed of conceptual mappings between the source domain and the target one. Therefore, this paper is trying to probe into the role of cognitive principles in idioms teaching, especially animal idioms from the contrastive analysis on Chinese "hu" idioms and English "lion" idioms. 展开更多
关键词 METAPHOR METONYMY metonymic mapping frame and profile conceptual integration cognitive culture
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RNA INTERFERENCE OF ANNEXIN II GENE IN PC3 CELLS BY USING SMALL INTERFERENCE RNA SYNTHESIZED WITH IN VITRO TRANSCRIPTION 被引量:1
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作者 Ya-wei Yuan Ai-min Sun +2 位作者 Ying Lui Long-hua Chen Banerjee A. G 《Chinese Medical Sciences Journal》 CAS CSCD 2007年第1期33-37,共5页
Objective To silence annexin Ⅱ gene expression by using small interference RNA (siRNA) in prostate cancer cell line PC3. Methods For in vitro transcription, four sequences of 29-nucleotide DNA template oligonucleo... Objective To silence annexin Ⅱ gene expression by using small interference RNA (siRNA) in prostate cancer cell line PC3. Methods For in vitro transcription, four sequences of 29-nucleotide DNA template oligonucleotides were designed, and one pair of the sequences were complementary to annexin Ⅱ gene. The other pair was negative control. The 8 nucleotides at the 3' end of each oligonucleotide were complementary to the T7 Promoter Primer. The sense and anti-sense siRNA templates were transcribed by T7 RNA polymerase and the resulting RNA transcripts were hybridized to create dsRNA. The siRNA was transfected into prostate cancer cell PC3. For assaying the efficiency of siRNA, confocal microscopy, Northern blotting, and Western blotting were employed to examine the expression of annexin Ⅱ protein and its mRNA. ^3H thymidine was used to measure DNA synthesis. Results The siRNA sequence specific to annexin Ⅱ gene was capable of inhibiting the expression of annexin Ⅱ protein and its mRNA. And cellular DNA synthesis was significantly reduced in siRNA transfected cells.Conclusions The protocol for the synthesis of siRNA by T7 RNA polymerase is feasible. Annexin Ⅱ might be involved in DNA synthesis. 展开更多
关键词 small interference RNA gene silencing annexin prostate cancer cell
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A novel fuzzy logic direct torque controller for a permanent magnet synchronous motor with a field programmable gate array 被引量:1
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作者 陈永军 《Journal of Chongqing University》 CAS 2008年第3期228-233,共6页
A high-performance digital servo system built on the platform of a field programmable gate array (FPGA),a fully digitized hardware design scheme of a direct torque control (DTC) and a low speed permanent magnet synchr... A high-performance digital servo system built on the platform of a field programmable gate array (FPGA),a fully digitized hardware design scheme of a direct torque control (DTC) and a low speed permanent magnet synchronous motor (PMSM) is proposed. The DTC strategy of PMSM is described with Verilog hardware description language and is employed on-chip FPGA in accordance with the electronic design automation design methodology. Due to large torque ripples in low speed PMSM,the hysteresis controller in a conventional PMSM DTC was replaced by a fuzzy controller. This FPGA scheme integrates the direct torque controller strategy,the time speed measurement algorithm,the fuzzy regulating technique and the space vector pulse width modulation principle. Experimental results indicate the fuzzy controller can provide a controllable speed at 20 r min-1 and torque at 330 N m with satisfactory dynamic and static performance. Furthermore,the results show that this new control strategy decreases the torque ripple drastically and enhances control performance. 展开更多
关键词 fuzzy control direct torque control field programmable gate array permanent magnet synchronous motor
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Polymorphism of glutathione S-transferase mu 1 and theta 1 genes and hepatocellular carcinoma in southern Guangxi, China 被引量:8
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作者 Zhuo-LinDeng Yi-PingWei YunMa 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第2期272-274,共3页
AIM: Glutathione S-transferase mu 1 (GSTM1) and theta 1 (GSTT1) genes are involved in the metabolism of a wide range of carcinogens, but deletions of the genes are commonly found in the population. The present study w... AIM: Glutathione S-transferase mu 1 (GSTM1) and theta 1 (GSTT1) genes are involved in the metabolism of a wide range of carcinogens, but deletions of the genes are commonly found in the population. The present study was undertaken to evaluate the association between GSTM1 and GSTT1 gene polymorphisms and hepatocellular carcinoma (HCC) risk. METHODS: The genetic polymorphisms were studied at an aflatoxin highly contaminated region in Guangxi, China. Pdymerase chain reaction (PCR) technique was used to detect the presence or absence of the GSTM1 and GSTT1 genes in blood samples. The case group was composed of 181 patients of HCC identified by the pathologists and the control group was composed of 360 adults without any tumor. RESULTS: The frequencies of GSTM1 and GSTT1 null genotypes in the control were 47.8% and 42.7%, while those in the HCC group were 64.6% and 59.7%, respectively. The differences between HCC group and control group were very significant (P<0.01). GSTM1 and GSTT1 combined null genotypes in HCC group and control group were 38.2% and 18.5% respectively, and the difference was significant (P<0.05). CONCLUSION: The GSTM1 and GSTT1 null genotypes are associated with an increased risk of HCC in a special geographic environment. Combination of the two null genotypes in an individual is substantially increased twice the risk of HCC. 展开更多
关键词 Hepatocellular carcinoma Glutathione S-transferase mu 1 Glutathione S-transferase theta 1 POLYMORPHISM
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Discursive Strategies of Contemporary Subcultures in the Global Context
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作者 CHEN Min 《Sino-US English Teaching》 2015年第3期220-225,共6页
Since the 20th century, the subculture, once a marginal cultural phenomenon, has been transformed into a global post-subculture. In this process, subcultural groups have undergone profound changes in multiple aspects.... Since the 20th century, the subculture, once a marginal cultural phenomenon, has been transformed into a global post-subculture. In this process, subcultural groups have undergone profound changes in multiple aspects. Hybridity, openness, and dissolution of depth become the keywords to understand youth subcultures. This paper is attempted to explore its discursive changes in comptemporary subcultures. By describing and interpreting the most popular subcultural discourse--hip-hop discourse, it is found that counter language often used in the subcultural discourse has been weakened and new strategies, such as code switching and semiotic games arise. The paper argues that with the transition of discursive strategies, subcultural groups attempt to weave the network of the global subcultures and create an interactive discursive space for global youth. 展开更多
关键词 SUBCULTURES GLOBALIZATION discursive strategies
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An edge-preserving algorithm of joint image restoration and volume reconstruction for rotation-scanning 4D echocardiographic images
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作者 GUO Qiang YANG Xin 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第6期960-968,共9页
A statistical algorithm for the reconstruction from time sequence echocardiographic images is proposed in this paper. The ability to jointly restore the images and reconstruct the 3D images without blurring the bounda... A statistical algorithm for the reconstruction from time sequence echocardiographic images is proposed in this paper. The ability to jointly restore the images and reconstruct the 3D images without blurring the boundary is the main innovation of this algorithm. First, a Bayesian model based on MAP-MRF is used to reconstruct 3D volume, and extended to deal with the images acquired by rotation scanning method. Then, the spatiotemporal nature of ultrasound images is taken into account for the pa-rameter of energy function, which makes this statistical model anisotropic. Hence not only can this method reconstruct 3D ul-trasound images, but also remove the speckle noise anisotropically. Finally, we illustrate the experiments of our method on the synthetic and medical images and compare it with the isotropic reconstruction method. 展开更多
关键词 ECHOCARDIOGRAPHY Image reconstruction ANISOTROPIC
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TCAR: A new network coding-aware routing mechanism based on local topology detection 被引量:2
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作者 王伟平 吴伟 +1 位作者 关庆娟 王建新 《Journal of Central South University》 SCIE EI CAS 2014年第8期3178-3185,共8页
Recent researches show that inter-session network coding could decrease the number of packets transmission and achieve higher throughput in wireless network compared with traditional forwarding mechanism. In most exis... Recent researches show that inter-session network coding could decrease the number of packets transmission and achieve higher throughput in wireless network compared with traditional forwarding mechanism. In most existing relay mechanisms based on inter-session network such as COPE, relay node demands to collect the messages from its neighbor nodes to get notice of which packets already overheard by them so as to determine whether there exists coding opportunity between or among forwarding packets. However, transmission overhead of this message collection and computing cost of opportunity determination will degrade the performance of these mechanisms. It is observed that coding opportunity at relay node is much more related with the local topology, and the opportunity of encoding three or more packets together is far less than that of encoding two packets together in wireless network with general density. Based on this, a new coding-aware routing mechanism, named TCAR, is proposed. TCAR ignores the oppommity of encoding three or more than three packets together. Each relay node maintains an encoding mapping table being established according to the result of its local topology detection, which can be used to calculate the path cost during routing setup phase, and determine that which two packets can be encoded together during the packets forwarding phase. In TCAR, instead of periodic messages collection, each relay nodes just need once local topology detection, and the encoding determination is much simpler than that of the former mechanisms. Simulation results show that compared with typical inter-session network coding mechanisms COPE and COPE-based routing, TCAR achieves 12% and 7% throughput gains, and keeps the minimum end to end delay. 展开更多
关键词 inter-session network coding coding aware routing wireless network
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Probe Gain without Probe field in a V-type System with an External Field Coupling Two Upper Levels
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作者 白艳锋 杨文星 喻小强 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第4期667-670,共4页
We report a new coherence and interference phenomenon in a V-type system with an external field coupling two upper levels. It is found that the probe gain can be generated even when no probe field is applied to the sy... We report a new coherence and interference phenomenon in a V-type system with an external field coupling two upper levels. It is found that the probe gain can be generated even when no probe field is applied to the system, we attribute this result to the existence of the external field. By comparing with the conventional probe gain, the probe gain without the probe field is enhanced greatly because of the absence of the population inversion term. 展开更多
关键词 the probe gain the population inversion
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MicroRNAs identification and bioinformatics analysis in large yellow croaker Larimichthys crocea using an integrated comparative and ab initio approach
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作者 FANG Luting XIAO Shijun +1 位作者 HAN Zhaofang WANG Zhiyong 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第5期1707-1719,共13页
MicroRNAs(miRNAs) are a group of small, endogenous, single-stranded non-coding RNAs that post-transcriptionally regulate gene expression levels. Previous studies have revealed that miRNAs play key roles in multiple bi... MicroRNAs(miRNAs) are a group of small, endogenous, single-stranded non-coding RNAs that post-transcriptionally regulate gene expression levels. Previous studies have revealed that miRNAs play key roles in multiple biological processes, such as growth and development in both animals and plants. Computational identification is an efficient method for miRNA prediction in organisms with a reference genome before high-throughput miRNA sequencing experiments. In this study, we employed an integrated strategy combining the homology-based and ab initio approaches to predict miRNAs from the genome and transcriptome of large yellow croaker, one of the most commercially important marine fish in China and East Asia. A total of 418 miRNA molecules, including 287 miRNAs by the homology-based method and 131 miRNAs by the ab initio approach, were identified for large yellow croaker. Additionally, 16 053 target genes were predicted and annotated for Gene Ontology(GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) databases. Meanwhile, we analysed single nucleotide polymorphisms(SNPs) around large yellow croaker miRNA and found that the miRNA seed regions were significantly less prone to mutations, indicating that the miRNA sequences were under strict natural selection based on their essential regulation functions in living cells. Twenty-two SNPs were identified in large yellow croaker miRNA seed regions, which dramatically influenced the miRNA-gene regulation networks. This is the first reported miRNA detection from both the genome and transcriptome using the integrated strategy for large yellow croaker species, and the miRNA and SNP analyses in this work provide important resources and a reference for subsequent miRNA functional investigations in large yellow croaker. 展开更多
关键词 large yellow croaker MIRNAS integrated computational approach
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Theoretical and Empirical Analysis on Influence Factors of Modern Agricultural Equipment Level in the Processof Agricultural Sustainable Development
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作者 Yan Tingwu Li Lingchao Wang Wang Ruixue 《Chinese Journal of Population,Resources and Environment》 2012年第1期105-110,共6页
To promote modem agricultural equipment level is one characteristic of constructing and developing modem agriculture in China. This paper makes up stepwise linear regression analysis model of influence factors of mode... To promote modem agricultural equipment level is one characteristic of constructing and developing modem agriculture in China. This paper makes up stepwise linear regression analysis model of influence factors of modem agricultural equipment level, and chooses rural labor, per capita income of rural residents, rural investment, proportion of people at secondary education level and at higher level in per hundred rural labor force and arable land area as independent variables, and total power of machine as induced variable. The major results show that the relativity of modem ag- ricultural equipment level, rural investment and education level of peasants is remarkable, and they are the major influence factors of modem agricultural equipment level. Raising investment level of rural infrastructure construction as well as and research and devel- opment and promotion of advanced and applicable modem agricultural equipment, improving quality and education level of peasants can accelerate the development of China's modern agricultural equipment effectively in the process of agricultural sustainable development. 展开更多
关键词 modern agricultural equipment level influence factors MODEL stepwise linear regression method agricultural sus-tainable development
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Epithelial-mesenchymal transition and cancermetastasis 被引量:7
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作者 Junjian Deng Ximing Xu 《The Chinese-German Journal of Clinical Oncology》 CAS 2011年第3期125-133,共9页
Epithelial-mesenchymal transition (EMT) is initially considered as a physiological phenomenon during the embryogenesis of mammals, as well as a basic biological event maintaining the stability of the vital body. Rec... Epithelial-mesenchymal transition (EMT) is initially considered as a physiological phenomenon during the embryogenesis of mammals, as well as a basic biological event maintaining the stability of the vital body. Recent researches indicated that EMT plays a critical role in various tumors progression, through which epithelial cancers invade and metastasize. The cell characteristics are changed during EMT, in which the cells lose cell-cell and cell-matrix interactions and apical polarity, reorganize their cytoskeleton, and become isolated, motile, as well as resistant to anoikis, then become spindle-shaped mesenchymal cells. This review lays emphasis on studying the cell morphogenesis, makers and molecular mechanism regulation about EMT, discussing the relationship between the EMT and the cancer development and metastasis. 展开更多
关键词 EMT molecular mechanism CANCER METASTASIS
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Fretting instability characteristics for gear shaft shoulder 被引量:1
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作者 贾国海 龚金科 +2 位作者 鄂加强 蔡皓 王曙辉 《Journal of Central South University》 SCIE EI CAS 2014年第10期3746-3752,共7页
In order to solve fretting instability problem of gear shaft shoulder due to torsional vibration in mechanical system, the mathematical model of fretting instability vibration of gear shaft shoulder was established by... In order to solve fretting instability problem of gear shaft shoulder due to torsional vibration in mechanical system, the mathematical model of fretting instability vibration of gear shaft shoulder was established by adopting the method of combining kinematics and tribology, and the numerical analysis was applied to the fretting instability mechanism of gear shaft shoulder by introducing the friction instability damping ratio. The numerical results show that the main factors causing the unstable and vibrating gear shaft shoulder are the large tightening torque and too large static friction coefficient. The reasonable values of the static friction coefficient, the amount of interference and tightening torque can effectively mitigate the fretting instability phenomenon of gear shaft shoulder. The experimental results verify that damping plays a significant role in eliminating the vibration of gear shaft control system. 展开更多
关键词 gear shaft shoulder torsional vibration KINEMATICS fretting friction instability damping ratio
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