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平欧杂种榛'达维'叶面积与叶片特征值的相关回归分析 被引量:2
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作者 于冬梅 《中国果树》 2017年第6期82-85,89,共5页
为获得平欧杂种榛叶面积简便、快捷的测定方法,分别于2011年7月和2012年7月,从6年生平欧杂种榛'达维'树上采集发育枝中段成熟叶片,以透明方格法和线性回归法测定叶面积结果表明:叶长、叶宽、叶长与叶宽乘积、叶长平方、叶宽平... 为获得平欧杂种榛叶面积简便、快捷的测定方法,分别于2011年7月和2012年7月,从6年生平欧杂种榛'达维'树上采集发育枝中段成熟叶片,以透明方格法和线性回归法测定叶面积结果表明:叶长、叶宽、叶长与叶宽乘积、叶长平方、叶宽平方与叶面积均呈正相关,其中以叶长与叶宽乘积与叶面积的复相关系数最高;以叶片特征值为因变量,以叶面积(Y)为应变量,采用逐步回归分析建立了叶面积二元回归方程,其中叶长(X_1)、叶长平方(X_1~2)和叶宽平方(X_2~2)是二元线性回归方程的3个自变量;通过对一元线性回归方程和二元线性回归方程的检验分析比较,确立了二元线性回归方程Y=67.248-13.917X_1+0.951 X_1~2+0.548X_2~2为平欧杂种榛'达维'叶面积回归方程。 展开更多
关键词 平欧杂交榛 '达维' 叶面积 叶形指数 相关回归分析
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喷施氨基酸硒叶面肥对榛子叶片质量和果实品质及矿质元素的影响 被引量:6
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作者 史祥宾 刘凤之 +3 位作者 王孝娣 施恢刚 魏长存 王海波 《中国果树》 2016年第6期48-51,共4页
以10年生平欧杂种榛‘达维’为试材,研究果实发育期喷施氨基酸硒叶面肥对其叶片质量、果实品质及矿质元素的影响。结果表明:喷施氨基酸硒叶面肥600倍液处理,‘达维’榛子叶片的鲜比叶重、干比叶重、叶绿素a含量、叶绿素b含量、总叶绿素... 以10年生平欧杂种榛‘达维’为试材,研究果实发育期喷施氨基酸硒叶面肥对其叶片质量、果实品质及矿质元素的影响。结果表明:喷施氨基酸硒叶面肥600倍液处理,‘达维’榛子叶片的鲜比叶重、干比叶重、叶绿素a含量、叶绿素b含量、总叶绿素含量及类胡萝卜素含量均显著高于喷清水(对照),分别提高30.61%、35.22%、42.56%、49.59%、44.02%和79.89%,明显改善叶片质量;显著增加果实单粒重、出仁率、脂肪含量和淀粉含量,分别提高29.20%、14.87%、10.63%和48.24%,改善果实品质;显著提高果实硒含量,达0.105 3 mg/kg,是对照的3.99倍;显著提高果实中N、Ca、Fe、Zn和B等矿质元素含量,分别提高7.03%、32.41%、97.70%、40.00%和188.89%,增加果实营养。综上所述,喷施氨基酸硒叶面肥是生产富硒榛子行之有效的方法。 展开更多
关键词 氨基酸硒 叶面肥 榛子 '达维’ 叶片质量 果实品质 矿质元素
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Alterations of Root and Fiber in Transgenic Cotton Plants with Chimeric Ph/P-ipt Gene Expression 被引量:16
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作者 于晓红 朱勇清 +4 位作者 陈晓亚 许智宏 周宝良 陈松 沈新莲 《Acta Botanica Sinica》 CSCD 2000年第1期59-63,共5页
The seed_specific phaseolin promoter (Ph/P) was fused to an ipt gene, then was cloned to a plant expression vector containing a gus gene driven by a 35S promoter. Cotton (Gossypium hirsutum L.) plants were tr... The seed_specific phaseolin promoter (Ph/P) was fused to an ipt gene, then was cloned to a plant expression vector containing a gus gene driven by a 35S promoter. Cotton (Gossypium hirsutum L.) plants were transformed through pollen tube pathway methods. After seed germination, histochemical staining of the roots demonstrated that 32 GUS positive plants were obtained and three of which contained the chimeric Ph/P_ ipt transgene as confirmed by PCR analysis. An immunosorbent assay showed that two of the three transgenic cotton lines contained higher levels of zeatin equivalents in seeds than the control. Seedling development of these two transgenic lines differed from the control in a reduction of the shoot growth, showing a stunted phenotype as expected, but a surprisingly developed root system with a 3-4 fold fast_growing lateral roots. In addition, fibers (seed_hairs) of the two transgenic cotton lines were considerably shorter than those of the control. These results indicate that genetic engineering may be used to manipulate the development of cotton plants, particularly cotton fibers. 展开更多
关键词 CYTOKININ transgenic cotton ROOT FIBER
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Expression Differences on Chinese Students' English Writing 被引量:1
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作者 侯晓蕾 《Sino-US English Teaching》 2006年第8期28-31,共4页
Writing is one of the difficulties that Chinese students come across during their English study. The differences between Chinese and English on thinking patterns and expressions are the main causes. This article discu... Writing is one of the difficulties that Chinese students come across during their English study. The differences between Chinese and English on thinking patterns and expressions are the main causes. This article discusses some problems existing in Chinese students' English writing, identifies the importance of cross-cultural awareness and ends with some measures in improving English writing teaching. 展开更多
关键词 English writing thinking patterns expression differences COUNTERMEASURES
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Differential Expression of APOEGene in Porcine Fetal Fibroblast Cells 被引量:1
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作者 李仕新 高萍 +3 位作者 陈赞谋 张豪 王翀 李加琪 《Agricultural Science & Technology》 CAS 2011年第6期904-907,共4页
[Objective]The aim was to study the differential expression ofAPOEgene in different generations of porcine fetal fibroblasts cells.[Method]The first,tenth,fifteenth,twentieth,twenty-fifth,fiftieth generations of porci... [Objective]The aim was to study the differential expression ofAPOEgene in different generations of porcine fetal fibroblasts cells.[Method]The first,tenth,fifteenth,twentieth,twenty-fifth,fiftieth generations of porcine fetal fibroblast cells,which were normally grown and passed,were collected before total RNA was extracted respectively.The expression ofAPOEgene in different generations of porcine fetal fibro-blast cells was detected by RT-PCR technique.[Result]The expression level of porcine APOE mRNA in the first generation of porcine fetal fi-broblast cells was the highest,and then it gradually decreased with the increase of cell generations and was the lowest in the fiftieth generation.[Conclusion]The expression ofAPOEgene had the selective trend in different generations of porcine fetal fibroblast cells. 展开更多
关键词 PIG Porcine fetal fibroblast cells SENESCENCE APOE Gene expression
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Gene Chip Analysis of Expression Pattern of Type I Inner Root Sheath (IRS) Keratin in AoHan Wool Sheep 被引量:3
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作者 余娟娟 刘积凤 +3 位作者 赵金山 程明 刘开东 柳楠 《Agricultural Science & Technology》 CAS 2012年第6期1171-1174,共4页
[Objective] The paper was to study the expression pattern of specific genes during wool anagen and telogen stages and its significance to AoHan wool sheep breeding. [Method] Gene chip technology was used to detect the... [Objective] The paper was to study the expression pattern of specific genes during wool anagen and telogen stages and its significance to AoHan wool sheep breeding. [Method] Gene chip technology was used to detect the expression of epithelial genes in neck and groin during anagen and telogen stages in AoHan wool sheep. [Result] The expression of type Ⅰ IRS keratin genes KRT25, KRT26, KRT27 and KRT28 in neck and groin of wool sheep were statistically analyzed, and the result showed that the expression in neck during anagen stage was significantly higher than that in groin (The multiple was more than two times, P0.01). The expression changes of the genes during anagen and telogen stages were compared, and the results showed that the expression of all Type I IRS Keratin genes performed in groin showed significant decrease from anagen stage to telogen stage (P 0.05), the expression changes of other genes were two times higher, except KRT25 (LOC443079). [Conclusion] The result indicated that the expression of type Ⅰ IRS Keratin genes is closely related with the control of wool density in specific part and the whole wool development cycle. 展开更多
关键词 Atractylodes lance(Thunb.)DC. Orthogonal Design HORMONE Substrate
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Compensation for the Influence of Radar-Target Relative Speed on Step Frequency MMW Target Identification
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作者 杨军 祁载康 《Journal of Beijing Institute of Technology》 EI CAS 1998年第4期380-387,共8页
Aim To study the influence of radar-target relative speed on frequency MMW high-resolution ore-dimension distance profile and the compensation for it. Methods Based on the distance travelled by the electromagnetic wa... Aim To study the influence of radar-target relative speed on frequency MMW high-resolution ore-dimension distance profile and the compensation for it. Methods Based on the distance travelled by the electromagnetic wave, analyses were made for the compensation algorithm and the expression of the inverse FFT base distance was given.The relative importance of different compensation terms was studied in great detail. The concept of searching compensation was put forward. Results and Condclusion Dcm-△Dvimis the be distance of inverse FFT transformation, the effect caused by the distance △Dim on one-dimension profile is negligible, and the effect caused by the distance Dvim should not be neglected and must be compensated. 展开更多
关键词 MMW millimeter wave radar step frequency one-dimension distance profile velocity compensation
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Influence of heme oxygenase-1 expression on immune liver fibrosis induced by cobalt protoporphyrin in rats 被引量:15
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作者 Fei Wang Zhi-Jun Duan Ying-Jie Sun 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第24期3009-3014,共6页
AIM:To investigate the effect of heme oxygenase-1 (HO-1)expression on immune liver fibrosis induced by cobalt protoporphyrin(CoPP)in rats. METHODS:An immune liver fibrosis model of rat was established by administering... AIM:To investigate the effect of heme oxygenase-1 (HO-1)expression on immune liver fibrosis induced by cobalt protoporphyrin(CoPP)in rats. METHODS:An immune liver fibrosis model of rat was established by administering human serum albumin (HSA).The rats were divided into CoPP,liver fibrosis and normal control groups.Rats in the CoPP group received intraperitoneal CoPP concurrently with HSA. Expression of HO-1 protein was observed by Western blotting and immunohistochemistry.Hematoxylin and eosin(HE)staining was performed to assess fibrosis proliferation and distribution,proliferation extent of fibroblasts,and alterations in hepatocytes and inflammatory cells.TypeⅠandⅢcollagens were detected with Van Gieson’s(VG)staining and Foot’s reticular fiber staining,respectively.In addition, spindle-shaped cells existing at perisinusoidal locations beyond portal and septa areas were investigated with HE staining. RESULTS:Western blotting and immunohistochemistry showed that the expression of HO-1 protein was higher in the CoPP group than in the liver fibrosis group(P<0.05).Compared with the liver fibrosis group,the serological index of hepatic fibrosis in the CoPP group decreased significantly(P<0.05).HE,VG and Foot’s staining revealed that administration of CoPP reduced the extent of hepatic fibrosis.The levels of serological indicators and the number of spindle-shaped cells at perisinuous locations beyond the portal and septa areas were reduced in the CoPP group.Only a few inflammatory cells were seen around the portal areas and central veins in the CoPP group. CONCLUSION:Increased endogenous HO-1 may suppress liver fibrosis by protecting liver cells, inhibiting inflammatory cell infiltration and hepatic stellate cell transformation. 展开更多
关键词 Heme oxygenase-1 Cobalt protoporphyrin Immune liver fibrosis Rats
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THE SYSTEM SIMULATION OF THREE-DIMENSIONAL RADAR 被引量:3
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作者 ZhangWei XiangJingcheng WangXuegang 《Journal of Electronics(China)》 2004年第5期407-412,共6页
To provide a test platform for Electronic Warfare (EW) system, it is needed to simulate the radar received Intermediate Frequency (IF) signals and radar system functions.This letter gives a description of a radar syst... To provide a test platform for Electronic Warfare (EW) system, it is needed to simulate the radar received Intermediate Frequency (IF) signals and radar system functions.This letter gives a description of a radar system simulation software developed for frequencyphase scanning three-dimensional (3-D) radar. Experimental results prove that the software could be used for system evaluation and for training purposes as an attractive alternative to real EW system. 展开更多
关键词 System simulation Electronic Warfare(EW) Three-dimensional(3-D) radars Intermediate Frequency (IF) signals
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MONO-PULSE RADAR 3-D IMAGING TECHNIQUES FOR TARGET IN STEPPED TRACKING MODE 被引量:1
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作者 Zhang Tao Ma Changzheng Zhang Qun Zhang Shouhong(Key Lab. for Radar Signal Processing, Xidian University, Xi’an 710071) (Beijing University of Posts & Telecommunications, Beijing 100876) 《Journal of Electronics(China)》 2002年第2期113-119,共7页
A method for mono-pulse radar 3-D imaging in stepped tracking mode is presented and the amplitude linear modulation of error signals in stepped tracking mode is analyzed with its compensation method followed, so the p... A method for mono-pulse radar 3-D imaging in stepped tracking mode is presented and the amplitude linear modulation of error signals in stepped tracking mode is analyzed with its compensation method followed, so the problem of precisely tracking of target is solved. Finally the validity of these methods is proven by the simulation results. 展开更多
关键词 Mono-pulse radar 3-D imaging Stepped tracking
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One-dimensional consolidation of double-layered soil with non-Darcian flow described by exponent and threshold gradient 被引量:10
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作者 李传勋 谢康和 +1 位作者 胡安峰 胡白香 《Journal of Central South University》 SCIE EI CAS 2012年第2期562-571,共10页
Based on non-Darcian flow law described by exponent and threshold gradient within a double-layered soil, the classic theory of one-dimensional consolidation of double-layered soil was modified to consider the change o... Based on non-Darcian flow law described by exponent and threshold gradient within a double-layered soil, the classic theory of one-dimensional consolidation of double-layered soil was modified to consider the change of vertical total stress with depth and time together. Because of the complexity of governing equations, the numerical solutions were obtained in detail by finite difference method. Then, the numerical solutions were compared with the analytical solutions in condition that non-Darcian flow law was degenerated to Dary's law, and the comparison results show that numerical solutions are reliable. Finally, consolidation behavior of double-layered soil with different parameters was analyzed, and the results show that the consolidation rate of double-layered soil decreases with increasing the value of exponent and threshold of non-Darcian flow, and the exponent and threshold gradient of the first soil layer greatly influence the consolidation rate of double-layered soil. The larger the ratio of the equivalent water head of external load to the total thickness of double-layered soil, the larger the rate of the consolidation, and the similitude relationship in classical consolidation theory of double-layered soil is not satisfied. The other consolidation behavior of double-layered soil with non-Darcian flow is the same as that with Darcy's law. 展开更多
关键词 one-dimensional consolidation double-layered soil non-Darcian flow depth dependent vertical total stress timedependent loading
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Computationally Efficient 2DDOA Estimation for Uniform Planar Arrays:RDROOTMUSIC Algorithm 被引量:3
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作者 YE Changbo ZHU Beizuo +1 位作者 LI Baobao ZHANG Xiaofei 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2021年第4期685-694,共10页
The problem of two-dimensional direction of arrival(2D-DOA)estimation for uniform planar arrays(UPAs)is investigated by employing the reduced-dimensional(RD)polynomial root finding technique and 2D multiple signal cla... The problem of two-dimensional direction of arrival(2D-DOA)estimation for uniform planar arrays(UPAs)is investigated by employing the reduced-dimensional(RD)polynomial root finding technique and 2D multiple signal classification(2D-MUSIC)algorithm.Specifically,based on the relationship between the noise subspace and steering vectors,we first construct 2D root polynomial for 2D-DOA estimates and then prove that the 2D polynomial function has infinitely many solutions.In particular,we propose a computationally efficient algorithm,termed RD-ROOT-MUSIC algorithm,to obtain the true solutions corresponding to targets by RD technique,where the 2D root-finding problem is substituted by two one-dimensional(1D)root-finding operations.Finally,accurate 2DDOA estimates can be obtained by a sample pairing approach.In addition,numerical simulation results are given to corroborate the advantages of the proposed algorithm. 展开更多
关键词 uniform planar array(UPA) direction of arrival(DOA)estimation RD-ROOT-MUSIC algorithm
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Differential gene expression during capillary morphogenesis in a microcarrier-based three-dimensional in vitro model of angiogenesis with focus on chemokines and chemokine receptors 被引量:3
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作者 Xi-TaiSun Min-YueZhang +5 位作者 ChangShu QiangLi Xiao-GuiYan NiCheng Yu-DongQiu Yi-TaoDing 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第15期2283-2290,共8页
AIM:To globally compare the gene expression profiles during the capillary morphogenesis of human microvascular endothelial cells (HMVECs) in an in vitro angiogeness system with affymetrix oligonucleotide array. METHOD... AIM:To globally compare the gene expression profiles during the capillary morphogenesis of human microvascular endothelial cells (HMVECs) in an in vitro angiogeness system with affymetrix oligonucleotide array. METHODS: A microcarrier-based in vitro angiogenesis system was developed, in which ECs migrated into the matrix, proliferated, and formed capillary sprouts. The sprouts elongated, branched and formed networks. The total RNA samples from the HMVECs at the selected time points (0.5, 24, and 72 h) during the capillary morphogenesis were used for microarray analyses, and the data were processed with the softwares provided by the manufacturers. The expression patterns of some genes were validated and confirmed by semi-quantitative RT-PCR. The regulated genes were grouped based on their molecular functions and expression patterns, and among them the expression of chemokines and chemokine receptors was specially examined and their functional implications were analyzed. RESULTS: A total of 1 961 genes were up- or downreg-ulated two-folds or above, and among them, 468 genes were up- or down-regulated three-folds or above. The regulated genes could be grouped into categories based on their molecular functions, and were also clustered into six groups based on their patterns of expression. As for chemokines and chemokine receptors, CXCL1/GRO-α, CXCL2/GRO-β, CXCL5/ENA-78, CXCL6/GCP2, IL-8/CXCL8, CXCL12/SDF-1, CXCL9/Mig, CXC11/ITAC, OOCL1/fractalkine, CCL2/MCP-1, CCL3, CCL5/RANTES, CCL7, CCL15, CCL21, CCL23, CCL28, and CCR1, CCR9, CXCR4 were identified. Moreover, these genes demonstrated different changing patterns during the capillary morphogenesis, which implied that they might have different roles in the sequential process. Among the chemokines identified, CCL2/MCP-1, CCL5/RANTES and CX3CL1 were specially up-regulated at the 24-h time point when the sprouting characterized the morphological change. It was thus suggested that they might exert crucial roles at the early stage of angiogenesis. CONCLUSION: The present study demonstrates a global profile of gene expression during endothelial capillary morphogenesis, and the results provide us much information about the molecular mechanisms of angiogenesis, with which further evaluation of individual genes can be conducted. 展开更多
关键词 ANGIOGENESIS In vitro model Endothelial cell Oligonucleotide array
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Expression of Neuropilin-1 Gene in Bone Marrow Stromal Cells from Patients with Myeloid Leukemia and Normal Individuals
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作者 宿颖 王震 +4 位作者 吴秀丽 黄梅娟 陈少华 杨力建 李扬秋 《The Chinese-German Journal of Clinical Oncology》 CAS 2005年第3期171-173,190,共4页
Objective: To investigate the expression of neuropilin-1 (NP-1) gene in bone marrow stromal cells (BMSCs) from myeloid leukemia (AML and CML) and normal individuals. Methods: Mononuclear cells were isolated from bone ... Objective: To investigate the expression of neuropilin-1 (NP-1) gene in bone marrow stromal cells (BMSCs) from myeloid leukemia (AML and CML) and normal individuals. Methods: Mononuclear cells were isolated from bone marrow (BM) of CML (14 cases), AML (12 cases) and normal individuals (20 cases). Adherent cells (i.e. BMSCs) were collected after long-term culture in vitro. The expression of NP-1 gene in three groups was detected respectively by reverse-transcription polymerase chain reaction (RT-PCR). Results: The long-term culture of BMSCs was successfully established. The expression level of NP-1 gene was significantly lower in BMSCs from AML (47.1%) and CML (50%) than in normal individuals (85%). Conclusion: NP-1 gene is expressed in BMSCs from some AML or CML patients and most normal individuals. The low-expression of NP-1 gene in BMSCs from AML or CML patients might be related with abnormality of regulation in hematopoiesis. 展开更多
关键词 neuropilin-1 gene myeloid leukemia bone marrow stromal cell
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Fibrinogen-like protein 2 fibroleukin expression and its correlation with disease progression in murine hepatitis virus type 3-induced fulminant hepatitis and in patients with severe viral hepatitis B 被引量:26
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作者 Chuan-Long Zhu Wei-Ming Yan +6 位作者 Fan Zhu Yong-Fen Zhu Dong Xi De-Ying Tian Gary Levy Xiao-Ping Luo Qin Ning 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第44期6936-6940,共5页
AIM: To evaluate the expression of fibrinogenlike protein 2 (fgl2) and its correlation with disease progression in both mice and patients with severe viral hepatitis. METHODS: Balb/cJ or A/J mice were infected int... AIM: To evaluate the expression of fibrinogenlike protein 2 (fgl2) and its correlation with disease progression in both mice and patients with severe viral hepatitis. METHODS: Balb/cJ or A/J mice were infected intraperitoneally (ip) with 100 PFU of murine hepatitis virus type 3 (MHV-3), liver and serum were harvested at 24, 48, and 72 h post infection for further use. Liver tissues were obtained from 23 patients with severe acute chronic (AOC) hepatitis B and 13 patients with mild chronic hepatitis B. Fourteen patients with mild chronic hepatitis B with cirrhosis and 4 liver donors served as normal controls. In addition, peripheral blood mononuciear cells (PBMC) were isolated from 30 patients (unpaired) with severe AOC hepatitis B and 10 healthy volunteers as controls. Procoagulant activity representing functional prothrombinase activity in PBMC and white blood cells was also assayed. A polyclonal antibody against fgl2 was used to detect the expression of both mouse and human fgl2 protein in liver samples as well as in PBMC by immunohistochemistry staining in a separate set of studies. Alanine aminotransferase (ALT) and total bilirubin (TBil) in serum were measured to assess the severity of liver injury.RESULTS: Histological changes were found in liver sections 12-24 h post MHV-3 infection in Balb/cJ mice. In association with changes in liver histology, marked elevations in serum ALT and TBil were observed. House fgl2 (mfgl2) protein was detected in the endothelium of intrahepatic veins and hepatic sinusoids within the liver 24 h after MHV-3 infection. Liver tissues from the patients with severe AOC hepatitis B had classical pathological features of acute necroinflammation. Human fgl2 (hfgl2) was detected in 21 of 23 patients (91.30%) with severe AOC hepatitis B, while only 1 of 13 patients (7.69%) with mild chronic hepatitis B and cirrhosis had hfgl2 mRNA or protein expression. Twenty-eight of thirty patients (93.33%) with severe AOC hepatitis B and 1 of 10 with mild chronic hepatitis B had detectable hfgl2 expression in PBMC. No hfgl2 expression was found either in the liver tissue or in the PBMC from normal donors. There was a positive correlation between hfgl2 expression and the severity of the liver disease as indicated by the levels of TBil. PCA significantly increased in PBMC in patients with severe AOC hepatitis B. CONCLUSION: The molecular and cellular results reported here in both mice and patients with severe viral hepatitis suggest that virus-induced hfgl2 prothrombinase/fibroleukin expression and the coagulation activity associated with the encoded fgl2 protein play a pivotal role in initiating severe hepatitis. The measurement of hfgl2/fibroleukin expression in PBMC may serve as a useful marker to monitor the severity of AOC hepatitis B and a target for therapeutic intervention. 展开更多
关键词 Viral hepatitis FGL2 Murine hepatitis virus Gene expression
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Expression of PEPT2 mRNA in the lung of rat with bleomycin-induced pulmonary fibrosis 被引量:1
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作者 Li Li Dianhua Wang +1 位作者 Xuan Zhang Xing Song 《The Chinese-German Journal of Clinical Oncology》 CAS 2013年第10期468-472,共5页
Objective:Pulmonary fibrosis is a common pathological phenomena in lung cancer patients after chemotherapy or radiotherapy, which is a key factor hindering to transport ion of high concentrated drug to the lung tissu... Objective:Pulmonary fibrosis is a common pathological phenomena in lung cancer patients after chemotherapy or radiotherapy, which is a key factor hindering to transport ion of high concentrated drug to the lung tissue, peptide trans-porter has become targets of the rational design of peptides and peptide drug. The purpose of the study is to investigate the expression of PEPT2 mRNA in the lung of rats with bleomycin (BLM)-induced pulmonary fibrosis. Methods:Fifty healthy adult Spragne-Dawley rats were randomized into five groups, the rats in BLM 7d, 14d and 28d groups were treated with a single instil ation of 5 mg/kg of BLM, to induced pulmonary fibrosis models. On days 7, 14 and 28, the animals were kil ed by exsan-guination respectively. Normal saline (NS) group were treated by NS, on days 14, the animals were kil ed by exsanguinations. Control group were untreated. The lung samples were processed for light microscopy and determined the hydroxyproline (HYP) concentration. The expression of PEPT2 mRNA were measured by RT-PCR. PEPT2 cDNA fragments were tested by dideoxy chain termination. Results:Compared with control and NS group, HYP levels increased on day 7 of BLM group, but there was no statistical significant dif erence (P〉0.05). HYP levels markedly increased on days 14 and 28 of BLM group, there was statistical significant dif erence (P〈0.01). The morphological study showed that col agenous fiber proliferated on days 14 and 28 of BLM group, especial y on day 28, formed pulmonary fibrosis. There were no significant changes of pulmo-nary PEPT2 mRNA expression at dif erent groups (P〉0.05). Conclusion:The pulmonary fibrosis models of SD rats can be induced by a single instil ation of 5 mg/kg of bleomycin on 28d. There were no significant changes of PEPT2 mRNA expression in the lung of rats with bleomycin-induced pulmonary fibrosis. 展开更多
关键词 PEPT2 bleomycin pulmonary fibrosis hydroxyproline
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3D prestack reverse time migration of ground penetrating radar data based on the normalized correlation imaging condition
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作者 Wang Hong-Hua Gong Jun-bo +4 位作者 Zhang Zhi Xiong Bin Lv Yu-zeng Feng De-shan Dai Qian-wei 《Applied Geophysics》 SCIE CSCD 2020年第5期709-718,901,共11页
The reverse time migration(RTM)of ground penetrating radar(GPR)is usually implemented in its two-dimensional(2D)form,due to huge computational cost.However,2D RTM algorithm is difficult to focus the scattering signal ... The reverse time migration(RTM)of ground penetrating radar(GPR)is usually implemented in its two-dimensional(2D)form,due to huge computational cost.However,2D RTM algorithm is difficult to focus the scattering signal and produce a high precision subsurface image when the object is buried in a complicated subsurface environment.To better handle the multi-off set GPR data,we propose a three-dimensional(3D)prestack RTM algorithm.The high-order fi nite diff erence time domian(FDTD)method,with the accuracy of eighth-order in space and second-order in time,is applied to simulate the forward and backward extrapolation electromagnetic fi elds.In addition,we use the normalized correlation imaging condition to obtain pre-stack RTM result and the Laplace fi lter to suppress the low frequency noise generated during the correlation process.The numerical test of 3D simulated GPR data demonstrated that 3D RTM image shows excellent coincidence with the true model.Compared with 2D RTM image,the 3D RTM image can more clearly and accurately refl ect the 3D spatial distribution of the target,and the resolution of the imaging results is far better.Furthermore,the application of observed GPR data further validates the eff ectiveness of the proposed 3D GPR RTM algorithm,and its fi nal image can more reliably guide the subsequent interpretation. 展开更多
关键词 Ground Penetrating Radar(GPR) 3D Reverse Time Migration(RTM) Finite Diff erence Time Domain(FDTD) Normalized correlation imaging condition
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Expression of matrix metalloproteinase-2 and tissue inhibitor of metalloproteinase-1 in hepatic stellate cells during rat hepatic fibrosis and its intervention by IL-10 被引量:35
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作者 Wei-DaZheng Li-JuanZhang Mei-NaShi Zhi-XinChen Yun-XinChen Yue-HongHuang Xiao-ZhongWang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第12期1753-1758,共6页
AIM: To investigate the expression of matrix metallopr-oteinase-2 and tissue inhibitor of metalloproteinase-1 in hepatic fibrosis and the antifibrogenic role of exogenous interleukin-10 (IL-10). METHODS: Hepatic fibro... AIM: To investigate the expression of matrix metallopr-oteinase-2 and tissue inhibitor of metalloproteinase-1 in hepatic fibrosis and the antifibrogenic role of exogenous interleukin-10 (IL-10). METHODS: Hepatic fibrosis was induced by CCI4 administration and 60 male Sprague-Dawley rats were randomly divided into normal control group (group N, 8 rats), CCI4-induced group (group C, 28 rats) and IL-10-treated group (group I, 24 rats). At the beginning of the 7th and 11th wk, rats in each group were routinely perfused with pronase E and type IV collagenase through portal vein catheter and the suspension was centrifuged by 11% Nycodenz density gradient to isolate hepatic stellate cells (HSCs). RT-PCR was used to analyze mRNA of MMP-2 and TIMP-1 from freshly isolated cells. Densitometric data were standardized with β-actin signals. Immunocytochemistry was performed to detect MMP-2 and TIMP-1 expression in HSC cultured for 72 h. RESULTS: Compared to group N in the 7th wk, MMP-2 and TIMP-1 mRNA increased in group C (P= 0.001/0.001) and group I (P= 0.001/0.009). The level of MMP-2 and TIMP-1 mRNA in group I was significantly lower than that in group C (P= 0.001/0.001). In the 11th wk, MMP-2 mRNA in group I was still lower than that in group C (P = 0.005), but both dropped compared with that in the 7th week (P = 0.001/0.004). TIMP-1 mRNA in group I was still lower than that in group C (P= 0.001), and increased in group C (P= 0.001) while decreased in group I (P = 0.042) compared with that in the 7th wk. Same results were found by immunocytochemistry. CONCLUSION: Expression of MMP-2 and TIMP-1 is increased in hepatic fibrosis. IL-10 exhibits an antifibrogenic effect by suppressing MMP-2 and TIMP-1 expression. 展开更多
关键词 RAT Hepatic fibrosis Hepatic stellate cells INTERLEUKIN-10 Matrix metalloproteinases-2 Tissue inhibitor of metalloproteinases-1
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Gene expression profiling defined pathways correlated with fibroblast cell proliferation induced by Opisthorchis viverrini excretory /secretory product 被引量:5
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作者 Chanitra Thuwajit Peti Thuwajit +4 位作者 Kazuhiko Uchida Daoyot Daorueang Sasithorn Kaewkes Sopit Wongkham Masanao Miwa 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第22期3585-3592,共8页
AIM: To investigate the mechanism of fibroblast cell proliferation stimulated by the Opisthorchis viverrini excretory/secretory (ES) product. METHODS: NIH-3T3, mouse fibroblast cells were treated with O. viverrini... AIM: To investigate the mechanism of fibroblast cell proliferation stimulated by the Opisthorchis viverrini excretory/secretory (ES) product. METHODS: NIH-3T3, mouse fibroblast cells were treated with O. viverrini ES product by non-contact co-cultured with the adult parasites. Total RNA from NIH-3T3 treated and untreated with O. viverrini was extracted, reverse transcribed and hybridized with the mouse 15K complementary DNA (cDNA) array. The result was analyzed by ArrayVision version 5 and GeneSpring version 5 softwares. After normalization, the ratios of gene expression of parasite treated to untreated NIH-3T3 cells of 2-and more-fold upregulated was defined as the differentially expressed genes. The expression levels of the signal transduction genes were validated by semiquantitative SYBR-based real-time RT-PCR. RESULTS: Among a total of 15 000 genes/ESTs, 239 genes with established cell proliferation-related function were 2 fold-and more-up-regulated by O. viverrini ES product compared to those in cells without exposure to the parasitic product. These genes were classified into groups including energy and metabolism, signal transduction, protein synthesis and translation, matrix and structural protein, transcription control, cell cycle and DNA replication. Moreover, the expressions of serinethreonine kinase receptor, receptor tyrosine kinase and collagen production-related genes were up-regulated by O.viverrini ES product, The expression level of signal transduction genes, pkC, pdgfra, jak 1, eps 8, tgfβ 1/4,strap and h ras measured by real-time RT-PCR confirmed their expression levels to those obtained from cDNA array. However, only the up-regulated expression of pkC,eps 8 and tgfβ3 1/4 which are the downstream signaling molecules of either epidermal growth factor (EGF) or transforming growth factor-β (TGF-β) showed statistical significance (P 〈 0.05).CONCLUSION: O. viverrini ES product stimulates the significant changes of gene expression in several functional categories and these mainly include transcripts related to cell proliferation. The TGF-β and EGF signal transduction pathways are indicated as the possible pathways of O. viverrini-driven cell proliferation. 展开更多
关键词 Gene expression profile Opisthorchis viverrini Excretory/secretory product cDNA array FIBROBLAST Cell proliferation Signal transduction Cholangiocarcinogenesis
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基于UKF的雷达和机载ESM扩维跟踪 被引量:6
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作者 张翔宇 王国宏 +1 位作者 王娜 张静 《国外电子测量技术》 2011年第9期30-32,39,共4页
为有效提高异类传感器融合跟踪的效果,提出了一种基于UKF的雷达和机载ESM扩维跟踪算法。首先将目标和机载ESM的状态信息组合起来,形成一个高维的状态向量,从而有效抑制滤波中GPS定位误差所带来的影响;接着在此基础上采用UKF来实现目标... 为有效提高异类传感器融合跟踪的效果,提出了一种基于UKF的雷达和机载ESM扩维跟踪算法。首先将目标和机载ESM的状态信息组合起来,形成一个高维的状态向量,从而有效抑制滤波中GPS定位误差所带来的影响;接着在此基础上采用UKF来实现目标的定位跟踪,以求进一步减小扩维后线性化误差加大等问题的影响。仿真结果表明,该算法可更好地实现对目标的定位跟踪。 展开更多
关键词 不敏卡尔曼滤波 扩维跟踪 雷达
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