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A Study of Linke Turbidity Factor over Qena / Egypt
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作者 Sayed M. Elshazly 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1996年第4期519-532,共14页
Data on instantaneous atmospheric Linke turbidity factor TL (m) are reported for clear days at Qena/Egypt in the period from June 1992 to May 1993.TL(m) is determined using the values of irradiance of direct solar rad... Data on instantaneous atmospheric Linke turbidity factor TL (m) are reported for clear days at Qena/Egypt in the period from June 1992 to May 1993.TL(m) is determined using the values of irradiance of direct solar radiation (I),which are calculated from global (G) and diffuse (D) - solar radiation measurements.Monthly and seasonally variations of both diurnal and daily average values of TL (m) increases steadily in the direction of sunset in the months from June to December 1992 as well as Summer and Autumn seasons,while it falls generally in this direction for the months from January to March and Winter season.In April and May,TL (m) fluctuates obviously through the day hours,it is also shown that the average values of TL(m) are particularly large during Summer months compared to other months of the year.This behavior of TL(m) is discussed in view of the variations of some weather elements,which affect the content of water vapor and dust particle in the atmosphere of the study region.It seems t be of similar trends to that of other locations inside and outside Egypt.The virtual variation of TL(m) is eliminated by reducing its value to relative optical air mass m=2,according to Kasten formula.The resulting TL (2) is more representative for the content of dust particles and water vapor in the atmosphere. 展开更多
关键词 TURBIDITY linke turbidity factor Seasonal and diurnal variations Solar radiations components measurements AEROSOL
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Integrin-linked kinase overexpression promotes epithelial-mesenchymal transition via nuclear factor-κB signaling in colorectal cancer cells 被引量:7
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作者 Hong Shen Jun-Li Ma +6 位作者 Yan Zhang Gan-Lu Deng Yan-Ling Qu Xiao-Ling Wu Jing-Xuan He Sai Zhang Shan Zeng 《World Journal of Gastroenterology》 SCIE CAS 2016年第15期3969-3977,共9页
AIM: To investigate the effect of integrin-linked kinase (ILK) on proliferation, metastasis, and invasion of the colorectal cancer cell line SW480.METHODS: In this study, the colorectal cancer cell line SW480 was stab... AIM: To investigate the effect of integrin-linked kinase (ILK) on proliferation, metastasis, and invasion of the colorectal cancer cell line SW480.METHODS: In this study, the colorectal cancer cell line SW480 was stably transfected with ILK plasmids, and small interfering RNA (siRNA) was used to knockdown expression of nuclear factor (NF)-&#x003ba;B/p65. Methylthiazole tetrazolium (MTT) assay was performed to measure proliferation, and the wound healing migration assay and matrigel invasion assay were used to test the metastasis and invasion ability of SW480 cells. To explore the epithelial-mesenchymal transition (EMT) process, embryonic development, and the invasion and metastasis of tumors, the protein level of E-cadherin, vimentin, snail, and slug was detected by western blot. Immunofluorescence was also used to detect E-cadherin expression. Western blot was used to determine the level of phosphorylated-inhibitor of kappa B (I&#x003ba;B)a, inhibitor of gamma B (I&#x003b3;B)a, and nuclear factor kappa B (NF-&#x003ba;B) expressions and to explore the ILK signaling pathway.RESULTS: Western blot results revealed that ILK expression significantly increased when ILK was overexpressed in SW480 cells (P &#x0003c; 0.05). Proliferation, metastasis, and invasion ability were improved in the vector-ILK group compared to the vector group (P &#x0003c; 0.05). Immunofluorescence results revealed that E-cadherin fluorescence intensity decreased after ILK was overexpressed (P &#x0003c; 0.05). Western blot results revealed that the protein expression of E-cadherin was reduced, while vimentin, snail, and slug were upregulated when ILK was overexpressed in SW480 cells (P &#x0003c; 0.05). In order to determine the role of the NF-&#x003ba;B signaling pathway in ILK overexpression promoted EMT occurrence, we overexpressed ILK in SW480 cells and found that levels of NF-&#x003ba;B/p65 and cytoplasmic phosphorylated-I&#x003ba;Ba were increased and that cytoplasmic I&#x0043a;Ba levels were decreased compared to the control group (P &#x0003c; 0.05). Furthermore, NF-&#x003ba;B/p65 knockout revealed that E-cadherin was increased in the overexpressed ILK group.CONCLUSION: ILK overexpression improved the proliferation, metastasis, and invasion ability of SW480 cells, and this effect may be mediated by the NF-&#x003ba;B signaling pathway. 展开更多
关键词 Colorectal cancer Integrin-linked kinase Epithelial-mesenchymal transition Nuclear factor B OVEREXPRESSION
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基于因子图的主从式AUV协同定位算法
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作者 王苏 黄鸿殿 +2 位作者 赵健文 周红进 李倩 《北京航空航天大学学报》 北大核心 2026年第2期436-444,共9页
针对无人自主水下航行器(AUV)集群高精度导航定位需求,提出一种基于因子图(FG)的主从式AUV协同定位算法。针对主从式AUV协同定位系统,构建系统状态方程和量测方程,并在此基础上构建相应因子图模型;根据和积算法(SPA)推导因子图中各节点... 针对无人自主水下航行器(AUV)集群高精度导航定位需求,提出一种基于因子图(FG)的主从式AUV协同定位算法。针对主从式AUV协同定位系统,构建系统状态方程和量测方程,并在此基础上构建相应因子图模型;根据和积算法(SPA)推导因子图中各节点间消息传递,通过因子图协同定位算法获得从艇位置变量节点概率密度函数(PDF)。利用陆上小车、GPS、惯性设备及数据链设备构建一主一从式协同定位试验平台并开展实际试验验证,结果表明:所提因子图协同定位算法相对于常规扩展卡尔曼滤波(EKF)协同定位算法,定位精度提高18.60%。同时,试验结果也表明测距误差对协同定位精度有较大影响。 展开更多
关键词 无人自主水下航行器 协同定位 因子图 扩展卡尔曼滤波 数据链
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高频AC-Link高压充电电源 被引量:1
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作者 张政权 刘庆想 +1 位作者 王庆峰 李伟 《电源学报》 CSCD 2017年第4期125-130,共6页
提出了一种基于AC-Link技术的新型充电电源,在各个工作过程都能实现零电流开关。采用电荷量分配的控制策略,分析电网电压对换流相位的影响。对输入线电流、线电流谐波和开关电流进行了仿真,最后进行了实验验证。实验结果表明:电源平均... 提出了一种基于AC-Link技术的新型充电电源,在各个工作过程都能实现零电流开关。采用电荷量分配的控制策略,分析电网电压对换流相位的影响。对输入线电流、线电流谐波和开关电流进行了仿真,最后进行了实验验证。实验结果表明:电源平均充电速率为62.5 kJ/s,功率密度为0.6 W/cm^3;电流波形能够很好地跟随电压波形,实现高的功率因数,每相总的电压谐波含量小于2%,总电流谐波含量小于10%;矩阵开关工作在软开关条件且实现软切换过程时,能够实现高的效率;在阻性条件下,效率为93%。 展开更多
关键词 充电电源 电荷量分配 功率因数
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面向船舶协同指挥控制系统的多维度安全防护系统设计
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作者 刘春 王洪磊 +1 位作者 薛婕 赵刚 《遥测遥控》 2026年第1期167-179,共13页
针对船舶协同指挥控制系统在复杂海上环境中面临的身份冒用、数据窃取、通信劫持及系统瘫痪等多元化安全挑战,本文提出一种多维纵深安全防护系统设计,该设计深度融合身份安全、数据安全、通信与接口安全、应急容灾四维防护机制,其核心... 针对船舶协同指挥控制系统在复杂海上环境中面临的身份冒用、数据窃取、通信劫持及系统瘫痪等多元化安全挑战,本文提出一种多维纵深安全防护系统设计,该设计深度融合身份安全、数据安全、通信与接口安全、应急容灾四维防护机制,其核心创新在于通过安全信息总线(SIB)实现跨维度安全信息的实时共享与策略协同联动,构建了“动态防御-主动免疫-受灾恢复”的安全闭环。通过生物特征与加密凭证多因素认证实现源头可信;依托上下文感知的数据分类与动态脱敏保障信息内容安全;采用链路与端到端加密协同及接口分级管控抵御信道与接入攻击;基于异常分级响应与热备份机制确保服务连续性。理论分析与典型应用场景验证表明,本系统能有效应对跨维度复合攻击,通过多维度协同联动显著增强了系统的整体韧性与任务可靠性,为船舶协同指挥控制系统提供了高适应性的安全保障范式。 展开更多
关键词 船舶协同指挥控制系统 多维度纵深安全防护 协同联动 安全信息总线 动态防御 动态数据脱敏 链路加密 多因素认证
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LinkMF:结合Linked Data的协同过滤推荐算法
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作者 黄山山 马军 +1 位作者 郭磊 王帅强 《中文信息学报》 CSCD 北大核心 2016年第1期85-92,共8页
协同过滤(CF)是推荐系统中应用最为广泛的推荐算法之一,然而数据稀疏性和冷启动问题是协同过滤方法的两个主要挑战。由于Linked Data整合了关于实体的丰富且结构化的特征,可以作为额外的信息源来缓解以上两种挑战。该文中我们首次提出... 协同过滤(CF)是推荐系统中应用最为广泛的推荐算法之一,然而数据稀疏性和冷启动问题是协同过滤方法的两个主要挑战。由于Linked Data整合了关于实体的丰富且结构化的特征,可以作为额外的信息源来缓解以上两种挑战。该文中我们首次提出了结合Linked Data改进CF推荐算法,基于矩阵分解提出了一种新的CF模型——LinkMF,在保证推荐准确度的基础上利用Linked Data缓解数据稀疏性和冷启动问题。首先,我们从Linked Data中抽取项目的特征表示并为项目建模;然后提出新的相似度度量方法计算项目相似度;最后利用项目相似度约束和指导MF分解过程产生推荐。在MovielLens和YAGO标准数据集上的大量实验结果表明,LinkMF优于现有的一些CF方法,特别在缓解数据稀疏性和冷启动问题上取得很好地效果。 展开更多
关键词 推荐系统 矩阵分解 linked DATA 数据稀疏性 冷启动
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Establishment of a Sandwich ELISA Method for Detection of Vascular Endothelial Growth Factor in Serum Samples of Hepatocellular Carcinoma Patients 被引量:4
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作者 BING SHAN CHEN GAO +10 位作者 JIAN-MING CHEN XIN-Yu BI BAO-YUN ZHANG YAN GUO CHEN-FANG DONG RUN AN QI SHI JING-QUN HU PING ZHAO JUN HAN XIAO-PING DONG 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2008年第1期69-74,共6页
Objective To establish a sandwich ELISA method for detecting vascular endothelial growth factor (VEGF) in sera of population and the patients with hepatocellular carcinoma (HCC). Methods Full length and two trunca... Objective To establish a sandwich ELISA method for detecting vascular endothelial growth factor (VEGF) in sera of population and the patients with hepatocellular carcinoma (HCC). Methods Full length and two truncated human VEGF cDNA sequences were amplified from a commercial plasmid pBLAST49-hVEGF by PCR and inserted into the prokaryotic-expression plasmid pET-32a or pGEX-2T. Various VEGF proteins were expressed and purified from E. coli in His-Trx or GST fusion forms. The specific VEGF antibodies were elicited in experimental rabbits and mice by immunization of the full length VEGF fusion protein His-Trx-VEGF1-165. After purification of antibodies with chromatograph of Protein G, a sandwich ELISA technique was established. Serum VEGF levels were evaluated in 229 adults and 291 HCC patients. Results SDS-PAGE displayed that the molecular weights of the expressed full length (His-Trx-VEGF1-165), N-terminal (His-Trx-VEGF1-100) and C-terminal (GST-VEGF100-165) human VEGF fusion proteins were about 38KD, 31KD, and 33KD, respectively. Western blots confirmed that the prepared antisera were able to recognize both prokaryoticly and eukaryoticly expressed recombinant VEGF proteins. Assays of serially diluted His-Trx-VEGF1-100 by the established sandwich ELISA method showed that the linear range of the standard curve was 0.625-320 ng/mL, with the squared correlation coefficient R^2=0.991. Screening of a serum panel containing 291 serum samples of HCC patients and 229 health adults revealed that the average VEGF level in HCC patients was higher than that in healthy controls, with a statically significant difference. Conclusion The established sandwich ELISA reflects the level of serum VEGF and provide scientific basis for screening metastasis and recurrence of HCC using serum VEGF as an index. 展开更多
关键词 Hepatocellular carcinoma Vascular endothelial growth factor Enzyme-linked immunosorbent assay
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Serological prevalence and risk factor analysis of hepatitis G virus infection in Hubei Province of China 被引量:8
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作者 De Ying Tian Dao Feng Yang +3 位作者 Ning Shao Xia Zheng Gang Zhang Hong Bo Lei Yuan Cheng Huang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2000年第4期585-587,共3页
Hepatitis G virus (HGV),also known as GB virus C, is a recently cloned virus which may be associated with human non A-E hepatitis[1,2] It is parenterally transmitted and usually coinfected or superinfected with hepat... Hepatitis G virus (HGV),also known as GB virus C, is a recently cloned virus which may be associated with human non A-E hepatitis[1,2] It is parenterally transmitted and usually coinfected or superinfected with hepatitis B or hepatitis C virus[3-5]. Some investigations have been reported on the seroprevalence and molecular prevalence of HGV infection in different areas and different population[6-15]. Current infection of HGV is diagnosed by detection of HGV RNA, and past infection with HGV is detectable by testing anti-HGV envelope protein (E2)[16-17]. To investigate the prevalence of HGV in Hubei Province, a central area of the People's Republic of China, ELISA and RT-PCR were employed to detect serum anti-HGV and HGV RNA in 1516 patients who were divided into 16 groups. 展开更多
关键词 HEPATITIS G virus enzyme linked immunoabsorbent assay risk factors POLYMERASE chain reaction PREVALENCE TRANSCRIPTION genetic
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Von Willebrand Factor Antigen and ADAMTS13 Activity Assay in Pregnant Women and Severe Preeclamptic Patients 被引量:4
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作者 张丹丹 肖娟 +7 位作者 黄浩梁 陈娟娟 刘涛 尹宗智 高单萍 刘琼 艾继辉 陈素华 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2010年第6期777-780,共4页
The present study examined von Willebrand factor (vWF) levels and ADAMTS13 activity in pregnant and severe preeclamptic women in order to shed light on the prothrombotic state in severe preeclampsia.Thirty healthy wom... The present study examined von Willebrand factor (vWF) levels and ADAMTS13 activity in pregnant and severe preeclamptic women in order to shed light on the prothrombotic state in severe preeclampsia.Thirty healthy women of childbearing age,22 second trimester pregnant women,30 third trimester pregnant women and 10 severe preeclamptic patients were recruited in this study.ADAMTS13 activity was determined by the FRETS-vWF73 assay and vWF antigen (vWF:Ag) levels by an enzyme-linked immunosorbent assay.The results showed that there were statistically significant differences in plasma vWF antigen levels between the severe preeclamptic and third trimester pregnant women,between third and second trimester pregnant women (P【0.05).The third trimester pregnant women had significantly lower plasma ADAMTS13 activity than second trimester pregnant women (P【0.05).Nevertheless,no significant differences in plasma ADAMTS13 activity were found between severe preeclamptic patients and the third trimester pregnant women (P】0.05).In conclusion,plasma ADAMTS13 activity is normal in severe preeclampsia despite the increased vWF:Ag levels.Prothrombotic state is involved in the pathogenesis of severe preeclampsia,as a result of endothelial injury. 展开更多
关键词 von Willebrand factor ADAMTS13 enzyme-linked immunosorbent assay fluorescence resonance energy transfer
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Serum vascular endothelial growth factor is a potential biomarker of metastatic recurrence after curative resection of hepatocellular carcinoma 被引量:20
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作者 Qi Niu Zhao You Tang +2 位作者 Zeng Chen Ma Lun Xiu Qin Lian Hai Zhang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2000年第4期565-568,共4页
Hepatocellular carcinoma (HCC) is one of the most common malignancies in China. To date, surgery is still the best solution to it. However, metastatic recurrences after curative hepatic resections are very common. Tan... Hepatocellular carcinoma (HCC) is one of the most common malignancies in China. To date, surgery is still the best solution to it. However, metastatic recurrences after curative hepatic resections are very common. Tang et al have reported that recurrence rate within 5 years of curative hepatic resection is 61.5% [1]. As curative hepatic resection has a high tendency for metastatic recurrence, therapeutic interventions such as transarterial embolization and antiangiogenesis have been tried to further improve prognosis of HCC patients. Therefore, establishing a dependable, sensitive, easy, and economical method to predict metastatic recurrence following curative hepatic resection is of clinical urgency. 展开更多
关键词 ENDOTHELIUM vascular ENDOTHELIAL growth factor carcinoma hepatocellular enzyme-linked IMMUNOSORBENT assay LIVER NEOPLASMS LIVER cirrhosis immunohistochemistry
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Determining capacity of multimodal multi-commodities freight transportation network from critical link volumes
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作者 许旺土 《Journal of Beijing Institute of Technology》 EI CAS 2012年第4期492-497,共6页
The commodity transportation capacity between all origin-destination ( OD ) pairs over the multimodal multi-commodities freight transportation network (MMFTN) is determined. A multi-ob- jectives mathematical model... The commodity transportation capacity between all origin-destination ( OD ) pairs over the multimodal multi-commodities freight transportation network (MMFTN) is determined. A multi-ob- jectives mathematical model is formulated for determining the OD capacity over the MMFTN accord- ing to a transporting capacity matrix that increased from the reference matrixes. The corresponding incremental factor for estimating the capacity matrix is obtained via the maximal likelihood estima- tion method that samples data of differences between the estimated commodity volumes and carrying capacities of the critical links. The proposed formulations are tested by an experimental highway and railroad freight transportation network in an existing literature. The relevant results of OD capacities are displayed and applicability of the algorithm is certified. 展开更多
关键词 network capacity multimodal multi-commodities transportation origin-destination(OD) matrix estimation critical links incremental factor maximum likelihood method
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DETERMINATION OF SERUM SOLUBLE MACROPHAGE COLONY-STIMULATING FACTOR RECEPTOR LEVELS IN PATIENTS WITH HEMATOLOGICAL DISEASES 被引量:1
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作者 饶青 韩敬淑 +4 位作者 沙晓津 杨仁池 耿以琪 郑国光 吴克复 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2001年第3期185-189,共5页
Objective: To investigate the serum levels of soluble macrophage colony-stimulating factor receptor (M-CSFsR) in normal subjects and patients with hematological diseases and its clinical implications in hematological ... Objective: To investigate the serum levels of soluble macrophage colony-stimulating factor receptor (M-CSFsR) in normal subjects and patients with hematological diseases and its clinical implications in hematological diseases. Methods: The concentration of M-CSFsR was determined by ELISA. The serum M-CSFsR was identified and characterized by immunoprecipitation and Western blotting. Results: The mean serum level of M-CSFsR of 123 normal individuals was 0.48 ng/ml ± 0.41 ng/ml. Immunoprecipitation and Western blotting assay revealed a ~ 90kD band of serum M-CSFsR. The mean serum M-CSFsR level of 60 patients with acute lymphoblastic leukemia (ALL), 36 patients with acute myeloblastic leukemia (AML), 13 patients with myelodysplastic syndrome (MDS) and 42 patients with aplastic anemia (AA) .were 0.22 ng/ml±0.23 ng/ml, 0.17 ng/ml±0.16 ng/ml, 0.19 ng/ml±0.16 ng/ml and 0.23 ng/ml±0.21 ng/ml, respectively, which were significantly lower than that of normal subjects (P=0.002 ,P<0.0001,P<0.0001 andP<0.0001). The mean serum M-CSFsR level of 51 idiopathic thrombocytopenic purpura (ITP) patients was significantly higher than that of normal subjects (2.05 ng/ml±2.75 ng/ml,P<0.0001). Conclusion: The serum M-CSFsR levels of patients with ALL, AML, MDS and AA were significantly lower, while the level of patients with ITP was significantly higher than that of normal individuals. Patients with severe ITP (platelet count<30×l09/L) had the highest M-CSFsR level. It suggested that the abnormal levels of serum M-CSFsR may associate with some hematological diseases and may contribute to the pathological process. 展开更多
关键词 Macrophage colony-stimulating factor RECEPTOR Enzyme linked immunosorbent assay IMMUNOPRECIPITATION Western blotting LEUKEMIA Idiopathic thrombocytopenic purpura
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Serum Vascular Endothelial Growth Factor-C and Vascular Endothelial Growth Factor Level in Patients with Colorectal Carcinoma and Clinical Significance 被引量:16
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作者 许天文 陈道达 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2006年第3期329-331,355,共4页
Circulating vascular endothelial growth factor-C (VEGF-C) and vascular endothelial growth factor (VEGF) levels in patients with colorectal carcinoma were determined in order to assess their clinical significance a... Circulating vascular endothelial growth factor-C (VEGF-C) and vascular endothelial growth factor (VEGF) levels in patients with colorectal carcinoma were determined in order to assess their clinical significance as a diagnostic tool for monitoring lymph node metastasis. In 66 patients with colorectal carcinoma and 30 healthy controls, circulating VEGF-C and VEGF levels were assessed by using enzyme-linked immunosorbent assay (ELISA). Serum VEGF-C and VEGF levels were higher in patients with colorectal carcinoma than in healthy controls. Patients with lymph node metastasis had higher serum VEGF-C and VEGF levels than those without lymph node metastasis. The levels of VEGF-C and VEGF were higher in the invasion group than in the non-invasion group. Serum VEGF-C levels reached a sensitivity of 81% and a specificity of 76 % with a cutoff value of 1438.0 pg/mL, whereas VEGF levels reached 72 % sensitivity and 74 % specificity at 240.2 pg/ mL. If 66 patients were divided into 4 groups according to the combined determination of VEGF-C and VEGF levels, the positive predictive value was 85.3 %, the negative predictive value was 94.6 %, and accuracy was 93.7 %. It was suggested that circulating VEGF-C levels might provide additional information for distinguishing the absence from presence of lymph node metastasis in patients with colorectal carcinoma. The combined determination of VEGF-C and VEGF levels could be used as an important index for preoperatively clinical stage of colorectal carcinoma. 展开更多
关键词 colorectal carcinoma vascular endothelial growth factor C vascular endothelial growth factor lymph node metastasis enzyme-linked immunosorbent assay
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Reduction of tumorigenicity of SMMC-7721 hepatoma cells by vascular endothelial growth factor antisense gene therapy 被引量:33
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作者 Yu Cheng Tang Yu Li Guan Xiang Qian Department of Biochemistry, Shanghai Second Medical University, Shanghai 200025, China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第1期22-27,共6页
AIM: To test the hypothesis to block VEGF expression of SMMC-7721 hepatoma cells may inhibit tumor growth using the rat hepatoma model. METHODS: Amplify the 200 VEGF cDNA fragment and insert it into human U6 gene cass... AIM: To test the hypothesis to block VEGF expression of SMMC-7721 hepatoma cells may inhibit tumor growth using the rat hepatoma model. METHODS: Amplify the 200 VEGF cDNA fragment and insert it into human U6 gene cassette in the reverse orientation transcribing small antisense RNA which could specifically interact with VEGF165, and VEGF121 mRNA. Construct the retroviral vector containing this antisense VEGF U6 cassette and package the replication-deficient recombinant retrovirus. SMMC-7721 cells were transduced with these virus and positive clones were selected with G418. PCR and Southern blot analysis were performed to determine if U6 cassette integrated into the genomic DNA of positive clone. Transfected tumor cells were evaluated for RNA expression by ribonuclease protection assays. The VEGF protein in the supernatant of parental tumor cells and genetically modified tumor cells was determined with ELISA. In vitro and in vivo growth properties of antisense VEGF cell clone in nude mice were analyzed. RESULTS: Restriction enzyme digestion and PCR sequencing verified that the antisense VEGF RNA retroviral vector was successfully constructed.After G418 selection, resistant SMMC-7721 cell clone was picked up. PCR and Southern blot analysis suggested that U6 cassette was integrated into the cell genomic DNA. Stable SMMC-7721 cell clone transduced with U6 antisense RNA cassette could express 200 bp small antisense VEGF RNA and secrete reduced levels of VEGF in culture condition. Production of VEGF by antisense transgene-expressing cells was 65+/-10 ng/L per 10(6) cells, 42045 ng/L per 10(6) cells in sense group and 485+/-30 ng/L per 10(6) cells in the negative control group, (P【 0.05). The antisense-VEGF cell clone appeared phenotypically indistinguishable from SMMC-7721 cells and SMMC-7721 cells transfected sense VEGF. The growth rate of the antisense-VEGF cell clone was the same as the control cells. When S.C. was implanted into nude mice, growth of antisense-VEGF cell lines was greatly inhibited compared with control cells. CONCLUSION: Expression of antisense VEGF RNA in SMMC-7721 cells could decrease the tumorigenicity, and antisense-VEGF gene therapy may be an adjuvant treatment for hepatoma. 展开更多
关键词 Gene Therapy Animals Carcinoma Hepatocellular Cell Division DNA Polymerase III Endothelial Growth factors Endothelium Vascular Enzyme-linked Immunosorbent Assay Gene Expression Humans Liver Neoplasms LYMPHOKINES MICE Mice Nude Neovascularization Pathologic Promoter Regions (Genetics) RNA Antisense Research Support Non-U.S. Gov't Transduction Genetic Tumor Cells Cultured Vascular Endothelial Growth factor A Vascular Endothelial Growth factors
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Discrete Choice Analysis of Temporal Factors on Social Network Growth
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作者 Kwok-Wai Cheung Yuk Tai Siu 《Intelligent Information Management》 2024年第1期21-34,共14页
Social networks like Facebook, X (Twitter), and LinkedIn provide an interaction and communication environment for users to generate and share content, allowing for the observation of social behaviours in the digital w... Social networks like Facebook, X (Twitter), and LinkedIn provide an interaction and communication environment for users to generate and share content, allowing for the observation of social behaviours in the digital world. These networks can be viewed as a collection of nodes and edges, where users and their interactions are represented as nodes and the connections between them as edges. Understanding the factors that contribute to the formation of these edges is important for studying network structure and processes. This knowledge can be applied to various areas such as identifying communities, recommending friends, and targeting online advertisements. Several factors, including node popularity and friends-of-friends relationships, influence edge formation and network growth. This research focuses on the temporal activity of nodes and its impact on edge formation. Specifically, the study examines how the minimum age of friends-of-friends edges and the average age of all edges connected to potential target nodes influence the formation of network edges. Discrete choice analysis is used to analyse the combined effect of these temporal factors and other well-known attributes like node degree (i.e., the number of connections a node has) and network distance between nodes. The findings reveal that temporal properties have a similar impact as network proximity in predicting the creation of links. By incorporating temporal features into the models, the accuracy of link prediction can be further improved. 展开更多
关键词 Discrete Choice Models Temporal factors Social Network link Prediction Network Growth
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Expression and Role of Integrin-linked Kinase and Collagen IV in Renal Allografts of Patients with Chronic Allograft Nephropathy 被引量:1
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作者 Shuiyong Xie Qiang Yan Weiguo Sui Hequn Zou 《器官移植内科学杂志》 2009年第1期14-21,共8页
关键词 胶原质 器官移植手术 肾脏移植物 患者 CAN
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Clinicopathological features of hypoxia-inducible factor-1α and vascular endothelial growth factor expression in patients with lung cancer 被引量:2
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作者 Xuli Yang Li Wang +4 位作者 Wenli Sai Yin Cai Juanjuan Gu Xin Chen Dengfu Yao 《Oncology and Translational Medicine》 2016年第6期261-267,共7页
Objective The aim of the study was to investigate the clinicopathological characteristics of hypoxiainducible factor-1α(HIF-1α) and vascular endothelial growth factor(VEGF) expression in patients with lung cancer.Me... Objective The aim of the study was to investigate the clinicopathological characteristics of hypoxiainducible factor-1α(HIF-1α) and vascular endothelial growth factor(VEGF) expression in patients with lung cancer.Methods Cancerous and noncancerous tissues were collected post-operation from 115 patients with lung cancers by the self-control method. Total RNA was extracted from the lung tissues. The status of tissue HIF-1α expression and intercellular distribution was observed by immunochemistry using a tissue microarray. The expression levels of circulating HIF-1α and VEGF were detected by enzyme-linked immunosorbent assay(ELISA).Results The expression of serum HIF-1α [(138.3 ± 28.8) μg/L] in the group of patients with lung cancer was significantly higher(P < 0.01) than that in the group of patients with pneumonia [(58.8 ± 14.5) μg/L] and the control group of patients ((24.1 ± 3.3) μg/L)There was a strong positive correlation of serum HIF-1α levels(r = 0.937, P < 0.01) with serum VEGF levels. The specific concentration of total RNA [(1.52 ± 1.14) μg/mg wet lung tissues] in the cancerous tissues was significantly higher(t = 8.494, P < 0.001) than that in the noncancerous tissues ((0.58 ± 0.33) μg/mg)The clinicopathological features of HIF-1α expression in lung cancer tissues revealed a significant relationship between positive HIF-1α expression and patient sex(χ~2 = 4.494, P = 0.034), tumor size(χ~2 = 4.679, P = 0.031), differentiation degree(χ~2= 8.846, P = 0.012), and presence of lymphatic node metastasis(χ~2= 6.604, P = 0.037).Conclusion Abnormal HIF-1α expression in lung cancer is closely related with nucleic acid metabolism and angiogenesis, and it may be helpful in the diagnosis and identification of lung cancer. 展开更多
关键词 lung cancer hypoxia-inducible factor-1α(HIF-1α) nucleic acid metabolism enzyme-linked immunosorbent assay(ELISA) DIAGNOSIS
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Luminal B型乳腺癌组织中XAF1、PCK1表达及与病人预后的关系 被引量:1
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作者 严萍萍 张绍东 +1 位作者 郭皎亮 窦燕东 《临床外科杂志》 2025年第1期97-101,共5页
目的探讨Luminal B型乳腺癌组织中X染色体连锁凋亡抑制蛋白相关因子1(XAF1)、磷酸烯醇丙酮酸羧激酶1(PCK1)表达及与病人预后的关系。方法2016年1月~2018年1月Luminal B型乳腺癌病人95例,均行手术治疗,术中收集癌组织及距离癌组织>5 c... 目的探讨Luminal B型乳腺癌组织中X染色体连锁凋亡抑制蛋白相关因子1(XAF1)、磷酸烯醇丙酮酸羧激酶1(PCK1)表达及与病人预后的关系。方法2016年1月~2018年1月Luminal B型乳腺癌病人95例,均行手术治疗,术中收集癌组织及距离癌组织>5 cm的癌旁组织,免疫组化法检测组织中XAF1、PCK1蛋白阳性表达情况。分析XAF1、PCK1蛋白表达与乳腺癌临床病理特征关系,采用Kaplan-Meier法绘制不同XAF1、PCK1蛋白表达乳腺癌病人的生存曲线,生存率的比较采用Log-rank检验,多因素Cox回归分析影响乳腺癌预后的相关因素。结果GEPIA数据库分析显示,乳腺癌组织中XAF1、PCK1 mRNA表达水平均低于正常组织,差异有统计学意义(P<0.05)。癌组织XAF1、PCK1蛋白阳性表达率分别低于癌旁组织,差异有统计学意义(P<0.05)。乳腺癌组织XAF1阳性表达与临床分期、淋巴结发生转移及组织学分级、Ki-67表达状态有关,PCK1阳性表达与临床分期、淋巴结发生转移及Ki-67表达状态有关(P<0.05)。XAF1阳性表达者5年总生存率高于阴性表达(Log-rank χ^(2)=5.101,P=0.024),PCK1阳性表达病人5年总生存率高于阴性表达(Log-rank χ^(2)=6.515,P=0.011)。临床分期Ⅲ期、XAF1阴性表达、PCK1阴性表达是不良预后的危险因素(P<0.05)。结论XAF1和PCK1在Luminal B型乳腺癌组织中阳性表达率降低,与部分临床病理特征及术后5年生存率有关,XAF1、PCK1阴性表达者术后5年生存率较差。 展开更多
关键词 乳腺癌 Luminal B型 X染色体连锁凋亡抑制蛋白相关因子1 磷酸烯醇丙酮酸羧激酶1 预后
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基于线图的双深度非负矩阵分解链路预测模型
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作者 郑淑兰 陈晓云 《福州大学学报(自然科学版)》 北大核心 2025年第3期253-260,共8页
提出一种基于线图的双深度非负矩阵分解(LDNMF)模型.首先引入线图来描述边与边的关系,其次对线图邻接矩阵和原邻接矩阵在相同基空间上进行深度非负矩阵分解,最后以分解后的重构邻接矩阵作为缺失链路预测的概率矩阵.在10个真实网络数据... 提出一种基于线图的双深度非负矩阵分解(LDNMF)模型.首先引入线图来描述边与边的关系,其次对线图邻接矩阵和原邻接矩阵在相同基空间上进行深度非负矩阵分解,最后以分解后的重构邻接矩阵作为缺失链路预测的概率矩阵.在10个真实网络数据集上进行缺失链路预测实验,结果表明,LDNMF模型比其他模型在受试者工作特征曲线下面积提升0.01%~2.43%,在精度上提升0.02%~2.20%,说明了引入线图的有效性. 展开更多
关键词 链路预测 深度非负矩阵分解 线图 图正则
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布罗索尤单抗在X连锁低血磷佝偻病治疗中的应用
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作者 韩思睿 姜艳 《中华骨质疏松和骨矿盐疾病杂志》 北大核心 2025年第4期463-471,共9页
布罗索尤单抗(Burosumab)是一种全人源成纤维细胞生长因子23(fibroblast growth factors 23,FGF23)单克隆抗体,是治疗X连锁低血磷佝偻病(X-linked hypophosphatemia,XLH)的新型药物,多项研究报告了布罗索尤单抗治疗XLH的安全性和有效性... 布罗索尤单抗(Burosumab)是一种全人源成纤维细胞生长因子23(fibroblast growth factors 23,FGF23)单克隆抗体,是治疗X连锁低血磷佝偻病(X-linked hypophosphatemia,XLH)的新型药物,多项研究报告了布罗索尤单抗治疗XLH的安全性和有效性,本文从药物机制、临床疗效及安全性等方面,综述布罗索尤单抗在XLH治疗中的应用。 展开更多
关键词 布罗索尤单抗 X连锁低血磷佝偻病 成纤维细胞生长因子23
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