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基于ASR抑制效果的粉煤灰物理、化学品质指标 被引量:1
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作者 丁建彤 白银 +1 位作者 蔡跃波 陈波 《建筑材料学报》 EI CAS CSCD 北大核心 2010年第4期424-429,共6页
为了全面反映粉煤灰化学、物理特性对其抑制混凝土碱硅反应(ASR)效果的影响,采用60℃快速混凝土棱柱体法考察了10种粉煤灰对ASR的抑制效果,采用XRD多相Rietveld定量分析方法测试粉煤灰的矿物组成,采用激光粒形粒度分析仪测试粉煤灰的比... 为了全面反映粉煤灰化学、物理特性对其抑制混凝土碱硅反应(ASR)效果的影响,采用60℃快速混凝土棱柱体法考察了10种粉煤灰对ASR的抑制效果,采用XRD多相Rietveld定量分析方法测试粉煤灰的矿物组成,采用激光粒形粒度分析仪测试粉煤灰的比表面积和平均粒径,同时测试粉煤灰45μm筛余,然后分别用粉煤灰非晶态SiO2含量、非晶态Al2O3含量、45μm筛余、平均粒径以及比表面积对其化学成分因子进行修正,得到粉煤灰的物理化学因子,并用文献数据对之进行了验证.结果表明,用粉煤灰中非晶态SiO2或非晶态Al2O3含量分别取代SiO2或Al2O3总量均不能改善ASR抑制率与化学成分因子之间的相关性;细度与化学成分组合而成的物化因子可以较全面地反映粉煤灰抑制ASR的能力. 展开更多
关键词 粉煤灰 碱硅反应 矿物组成 细度 Rietveld定量分析方法 颗粒粒径分布 化学成分因子 物化因子
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Vegetation Evolution in the Northern South China Sea Region Since 40 ka BP - An Attempt to Reconstruct Palaeovegetation Based on Biomization 被引量:3
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作者 罗运利 孙湘君 《Acta Botanica Sinica》 CSCD 2001年第11期1202-1206,共5页
Vegetation evolution in the northern South China Sea region since 40 500 a BP is reconstructed using biomization procedure based on pollen data from deep sea core 17940. The result shows that, it is feasible to recons... Vegetation evolution in the northern South China Sea region since 40 500 a BP is reconstructed using biomization procedure based on pollen data from deep sea core 17940. The result shows that, it is feasible to reconstruct palaeovegetation using biomization procedure, when pollen, particularly Pinus pollen, transported by mind over long distance is excluded. Results from factor analysis suggest that humidity and temperature are the two main factors determining vegetation evolution on land around the northern South China Sea. From 40 500 a BP to 11 100 a BP, broad-leaved evergreen forest (WAMF), and montane conifers(MGRF) occurred on hills and low mountains; while steppe (STEP) predominated on the exposed shelf. The main feature of the vegetation evolution is the frequent alternation between MGRF (or WAMF) and STEP, implying abrupt changes in millennium scale between humid/cold and dry/temperate climate. All abrupt climate events could be broadly correlated with Henrich events and Dansggard-Oscherge events. One of the events around 12 700 a BP, sees the occurrence of MGRF, suggesting that climate turned humid and cold rapidly. This may be correlated with the Younger Dryas event; Broad-leaved evergreen (WAMF) predominates since 11 000 a BP. During the early Holocene and late Holocene tropical rainforest (TRFO) or tropical seasonal forest (TSFO) occurred several times. 展开更多
关键词 POLLEN Biomization factor analysis South China Sea PALAEOVEGETATION
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Tortuosity factor for porous FeAl intermetallics fabricated by reactive synthesis 被引量:11
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作者 高海燕 贺跃辉 +2 位作者 ZOU Jin 徐南平 C.T.LIU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第9期2179-2183,共5页
The tortuosity factor is the most critical parameter for the pore characteristic of porous materials. The tortuosity factor for porous FeAl intermetallics was studied based on the Darcy law and Hagen-Poiseuille equati... The tortuosity factor is the most critical parameter for the pore characteristic of porous materials. The tortuosity factor for porous FeAl intermetallics was studied based on the Darcy law and Hagen-Poiseuille equation. Porous stainless steel with the same pore structure parameter as porous FeAl was fabricated by powder metallurgy method for comparison. The results show that the tortuosity factor of porous FeAl intermetallics is smaller than that of porous stainless steel when their pore structure parameters are the same. The average tortuosity factor is 2.26 for the porous FeAl material and 2.92 for the porous stainless steel, calculated by Hagen-Poiseuille equation. The reason of the different tortuosity factors for porous FeAl and porous stainless steel was also explored through studying the pore formation mechanisms of the two types of porous materials. 展开更多
关键词 FEAL INTERMETALLICS porous material tortuosity factor
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Primary Mechanisms for Novel Compound Pivanampeta Against Atherosclerosis in Rat and Rabbit Model of Atherosclerosis 被引量:1
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作者 山丽梅 张锦超 +1 位作者 赵艳玲 汪海 《Journal of Chinese Pharmaceutical Sciences》 CAS 2004年第1期68-75,共8页
Aim To investigate the anti-atherosclerotic mechanisms of the novel compoundpivanampeta in the early and later stages of atherosclerosis evolution. Methods Rats or rabbits wererandomly assigned to the control, the mod... Aim To investigate the anti-atherosclerotic mechanisms of the novel compoundpivanampeta in the early and later stages of atherosclerosis evolution. Methods Rats or rabbits wererandomly assigned to the control, the model and the pivanampeta-treated groups. The rats or rabbitsin the model group and the pivanampeta-treated group were fed with hypercholesterol diet. Thecarotids of rabbits were cut into pieces and stained with HE. The rat or rabbit serum levels of TC,LDL-CHO, HDL-CHO, IL-8, ET-1, PGI_2, TXA_2, and NO were assayed. The expressions of MCP-1 and IL-8mRNA on rabbit carotid were determined by semi-quantitative RT-PCR. Results Pivanampeta exerted aninhibitory effect on TXA_2 formation without PGI_2 production in the early and later stages ofatherosclerosis. The significantly increased release of NO and the decreased release of IL-8 in theanimals in pivanampeta-treated group were both detected in the rat atherosclerosis model. In therabbit atherosclerosis model the expressions of IL-8 and MCP-1 mRNA in pivanampeta-treated groupwere decreased significantly. However, the treatment with pivanampeta had no effect on the levels ofplasma cholesterol, MDA and SOD. Conclusion The increase of serum NO contents and the decrease ofplasma TXA_2 level, as well as its inhibition of expression of IL-8 and MCP-1 are probably involvedin the mechanisms underlying the anti-atherosclerotic effects of pivanampeta. 展开更多
关键词 ATHEROSCLEROSIS nitric oxide PGI_2 TXA_2
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Marker_Free: a Novel Tendency of Transgenic Plants 被引量:9
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作者 开国银 张磊 +3 位作者 张红宇 许铁峰 唐克轩 张汉明 《Acta Botanica Sinica》 CSCD 2002年第8期883-888,共6页
Marker free is a rapidly developed strategy that offers a new approach for the elimination of public concerns caused by the selectable marker genes conferring antibiotic or herbicide resistance and so on. Furthermore,... Marker free is a rapidly developed strategy that offers a new approach for the elimination of public concerns caused by the selectable marker genes conferring antibiotic or herbicide resistance and so on. Furthermore, marker_free transgenic plants (MFTPs) have a number of special advantages, such as decreasing the concerns about safety of selectable marker and stacking transgenes progressively into transgenic plants, which significantly owns potential application value. Major approaches developed recently for obtaining MFTPs were reviewed in this paper. 展开更多
关键词 marker_free transgenic plants (MFTPs) co_transformation CRE/LOX transposable element multi_auto_transformation (MAT) vector
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Archaeal and bacterial communities in acid mine drainage from metal-rich abandoned tailing ponds, Tongling, China 被引量:3
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作者 杨扬 李杨 孙庆业 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第10期3332-3342,共11页
To expand knowledge on microbial communities of various metal-rich levels of mine drainage environments in Anhui province, China, the archaeal and bacterial diversities were examined using a PCR-based cloning approach... To expand knowledge on microbial communities of various metal-rich levels of mine drainage environments in Anhui province, China, the archaeal and bacterial diversities were examined using a PCR-based cloning approach. Eight acid mine water samples were collected from five areas in Tongling. Phylogenetic analyses revealed that bacteria mainly fell into ten divisions, which were Betaproteobacteria, Gammaproteobacteria, Alphaproteobacteria, Deinococcus-Thermus, Nitrospira, Firmicutes, Actinobacteria, Deltaproteobacteria, Bacteroidetes, Chloroflexi. Archaea fell into three phylogenetic divisions, Thermoplasma, Ferroplasma and Thermogymnomonas. The unweighted pair group method with arithmetic mean(UPGMA) cluster analysis based on the microbial communities’ compositions revealed that five samples shared similarity with the dominance of Meiothermus and Thermomonas. Two samples had the preponderant existence of Acidithiobacillus and Leptospirillum. The remaining sample owned higher microbial communities’ diversity with the Shannon-Weaver H up to 2.91. Canonical correlation analysis(CCA) suggested that microbial community structures had great association with p H and the concentration of Hg2+, Pb2+, Fe3+, Cl-, SO2- 4in water. 展开更多
关键词 acid mine drainage microbial community clone library geochemical variables
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Hydrogen sulfide attenuates gastric mucosal injury induced by restraint water-immersion stress via activation of KATPchannel and NF-κB dependent pathway 被引量:7
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作者 Hong-Zhao Sun Shan Zheng +4 位作者 Kai Lu Feng-Tian Hou Jie-Xue Bi Xue-Lian Liu Shan-Shan Wang 《World Journal of Gastroenterology》 SCIE CAS 2017年第1期87-92,共6页
AIMTo explore the effect of hydrogen sulfide (H<sub>2</sub>S) on restraint water-immersion stress (RWIS)-induced gastric lesions in rats and the influence of adenosine triphosphate (ATP)-sensitive potassiu... AIMTo explore the effect of hydrogen sulfide (H<sub>2</sub>S) on restraint water-immersion stress (RWIS)-induced gastric lesions in rats and the influence of adenosine triphosphate (ATP)-sensitive potassium (K<sub>ATP</sub>) channels and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-&#x003ba;B) pathway on such an effect.METHODSMale Wistar rats were randomly divided into a control group, a physiological saline (PS) group, a sodium hydrosulfide (NaHS) group, a glibenclamide (Gl) group, Gl plus NaHS group, a pyrrolidine dithiocarbamate (PDTC) group, and a PDTC plus NaHS group. Gastric mucosal injury was induced by RWIS for 3 h in rats, and gastric mucosal damage was analyzed after that. The PS, NaHS (100 &#x003bc;mol/kg body weight), Gl (100 &#x003bc;mol/kg body weight), Gl (100 &#x003bc;mol/kg or 150 &#x003bc;mol/kg body weight) plus NaHS (100 &#x003bc;mol/kg body weight), PDTC (100 &#x003bc;mol/kg body weight), and PDTC (100 &#x003bc;mol/kg body weight) plus NaHS (100 &#x003bc;mol/kg body weight) were respectively injected intravenously before RWIS.RESULTSRWIS induced serious gastric lesions in the rats in the PS pretreatment group. The pretreatment of NaHS (a H<sub>2</sub>S donor) significantly reduced the damage induced by RWIS. The gastric protective effect of the NaHS during RWIS was attenuated by PDTC, an NF-&#x003ba;B inhibitor, and also by glibenclamide, an ATP-sensitive potassium channel blocker, in a dose-dependent manner.CONCLUSIONThese results suggest that exogenous H<sub>2</sub>S plays a protective role against RWIS injury in rats, possibly through modulation of K<sub>ATP</sub> channel opening and the NF-&#x003ba;B dependent pathway. 展开更多
关键词 Hydrogen sulfide Nuclear factor kappa B Gastric mucosal injury Restraint water-immersion stress Adenosine triphosphate-sensitive potassium
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Effects of IGF-Ⅱ on promoting proliferation and regulating nitric oxide synthase gene expression in mouse osteoblast-like cell 被引量:2
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作者 孙伟莲 陈莉丽 +1 位作者 严杰 余钟声 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2005年第7期699-704,共6页
Objective: To investigate the effects of insulin-like growth factor Ⅱ (IGF-Ⅱ) on promoting cell proliferation, regulating levels of cellular nitric oxide (NO) and mRNA transcriptions of inducible nitric oxide syntha... Objective: To investigate the effects of insulin-like growth factor Ⅱ (IGF-Ⅱ) on promoting cell proliferation, regulating levels of cellular nitric oxide (NO) and mRNA transcriptions of inducible nitric oxide synthase (iNOS) and endothelial NOS (eNOS) in mouse osteoblast-like cells. Methods: Mouse osteoblastic cell line MC3T3-E1 was selected as the effective cell of IGF-Ⅱ. After the cells were treated with IGF-Ⅱ at different concentrations for different time duration,3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) colorimetric assay was used to examine cell proliferation,and nitrate reductase method was applied to detect NO concentrations in cell culture supernatants and quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) was employed to determine transcription levels of cellular iNOS and eNOS mRNAs. Results: After the MC3T3-E 1 cells were treated with IGF-Ⅱ at concentration of 1 ng/ml for 72 h, 10 and 100 ng/ml for 24,48 and 72 h respectively, all the MTT values increased (P<0.05 or P<0.01) with obvious dosage-time dependent pattern. NO levels of the MC3T3-E1 cells treated with 100 ng/ml IGF-Ⅱ for 48 h, and with 1, 10 and 100 ng/ml IGF-Ⅱ for 72 h were remarkably lower than that of the normal control, respectively (P<0.05 or P<0.01). After the cells were treated with 100 ng/ml IGF-Ⅱ for 48 h cellular iNOS mRNA levels were significantly decreased (P<0.01). But the levels of eNOS mRNA in the cells treated with each of the used IGF-Ⅱ dosages for different time duration did not show any differences compared with the normal control (P>0.05).Conclusion: IGF-Ⅱ at different concentrations could promote proliferation of mouse MC3T3-E1 cell. This cell proliferation promotion was associated with the low NO levels maintained by IGF-Ⅱ. Higher concentration of IGF-Ⅱ could down-regulate iNOS gene expression at the level of transcription but not affect transcription of eNOS mRNA, which might be one of the mechanisms for IGF-Ⅱ maintenance of the low NO levels in MC3T3-E 1 cells. 展开更多
关键词 Insulin-like growth factor II OSTEOBLAST PROLIFERATION Nitric oxide synthase Nitric oxide Regulation
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Enhanced therapeutic effects of combined chemotherapeutic drugs and midkine antisense oligonucleotides for hepatocellular carcinoma 被引量:10
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作者 Li-Cheng Dai Xiang Wang +3 位作者 Xing Yao Yong-Liang Lu Jin-Liang Ping Jian-Fang He 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第13期1989-1994,共6页
AIM: To evaluate the effect of combined antisense oligonucleotides targeting midkine (MK-AS) and chemotherapeutic drugs [cisplatin(DDP), 5-fluorouracil (5-FU) and adriamycin (ADM)] on inhibition of HepG2 cell prolifer... AIM: To evaluate the effect of combined antisense oligonucleotides targeting midkine (MK-AS) and chemotherapeutic drugs [cisplatin(DDP), 5-fluorouracil (5-FU) and adriamycin (ADM)] on inhibition of HepG2 cell proliferation, and to analyze the efficacy of MK-AS used in combined ADM in in situ human hepatocellular carcinoma (HCC) model. METHODS: HepG2 cells were treated with MK-AS and/or chemotherapeutic drugs mediated by Lipofectin, and cell growth activity was determined by MTS assay. An in situ HCC model was used in this experiment. MK- AS, ADM and MK-AS + ADM were given intravenously for 20 d, respectively. The animal body weight and their tumor weight were measured to assess the effect of the combined therapy in vivo. RESULTS: Combined treatment with MK-AS reduced the IC50 of DDP, 5-FU and ADM in HepG2 cells. MK-AS significantly increased the inhibition rate of DDP, 5-FU and ADM. Additionally, synergism (Q 1.15) occurred at a lower concentration of ADM, 5-FU and DDP with combined MK-AS. Combined treatment with MK-AS and ADM resulted in the more growth inhibition on in situ human HCC model compared with treatment with chemotherapeutic drugs alone. CONCLUSION: MK-AS increases the chemosensitivity in HepG2 cells and in situ human HCC model, and thecombination of MK-AS and ADM has a much better in vitro and in vivo synergism. 展开更多
关键词 Antisense oligonucleotide MIDKINE CARCINOMA HEPATOCELLULAR Combination therapy
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Attenuation of portal hypertension by natural taurine in rats with liver cirrhosis 被引量:9
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作者 Jian Liang Xin Deng +2 位作者 Zhi-Xiu Lin Li-Chun Zhao Xi-Liu Zhang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第36期4529-4537,共9页
AIM: To investigate the inhibitory effect of natural taurine (NTau) on portal hypertension (PHT) in rats with experimentally-induced liver cirrhosis (LC). METHODS: Experimentally-induced LC Wistar rats (20 ra... AIM: To investigate the inhibitory effect of natural taurine (NTau) on portal hypertension (PHT) in rats with experimentally-induced liver cirrhosis (LC). METHODS: Experimentally-induced LC Wistar rats (20 rats/group) were treated with either oral saline or oral NTau for 6 consecutive weeks. Evaluation parameters included portal venous pressure (PVP), portal venous resistance (PVR), portal venous flow (PVF), splanchnic vascular resistance (SVR) and mean arterial pressure (NAP). Vasoactive substance levels including nitric oxide (NO), nitric oxide synthase (NOS) and cyclic guanosine monophosphate (cGMP) were also measured. Histological investigation of type Ⅰ and Ⅲ collagen (COL Ⅰ and Ⅲ) and transforming growth factor-β1 (TGF-β1) was also performed. RESULTS: Treatment with NTau (1) significantly decreased PVP, PVR and PVF, and increased MAP and SVP; (2) markedly increased the vascular compliance and reduced the zero-stress of the portal vein; (3) markedly decreased the amount of NO and cGMP and activity of NOS; and (4) improved the pathological status of the liver tissue and reduced the expression of COL Ⅰ, COL Ⅲ and TGF-β1. CONCLUSION: NTau inhibited the LC-induced PHT by improving hyperdynamic circulation, morphology of liver and biomechanical properties of the portal vein in experimentally-induced LC rats. 展开更多
关键词 TAURINE Liver cirrhosis Portal hypertension RAT
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Inflammatory cytokines promote inducible nitric oxide synthase-mediated DNA damage in hamster gallbladder epithelial cells 被引量:1
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作者 Amane Kitasato Yoshitsugu Tajima +4 位作者 Tamotsu Kuroki Ryuji Tsutsumi Tomohiko Adachi Takehiro Mishima Takashi Kanematsu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第47期6379-6384,共6页
AIM: To investigate the link between chronic biliary inflammation and carcinogenesis using hamster gallbladder epithelial cells. METHODS: Gallbladder epithelial cells were isolated from hamsters and cultured with a mi... AIM: To investigate the link between chronic biliary inflammation and carcinogenesis using hamster gallbladder epithelial cells. METHODS: Gallbladder epithelial cells were isolated from hamsters and cultured with a mixture of inflammatory cytokines including interleukin-1β,interferon-γ,and tumor necrosis factor-α. Inducible nitric oxide synthase (iNOS) expression,nitric oxide (NO) generation,and DNA damage were evaluated. RESULTS: NO generation was increased significantly following cytokine stimulation,and suppressed by an iNOS inhibitor. iNOS mRNA expression was demonstrated in the gallbladder epithelial cells during exposure to inflammatory cytokines. Furthermore,NO-dependent DNA damage,estimated by the comet assay,was significantly increased by cytokines,and decreased to control levels by an iNOS inhibitor. CONCLUSION: Cytokine stimulation induced iNOS expression and NO generation in normal hamster gallbladder epithelial cells,which was sufficient to cause DNA damage. These results indicate that NO-mediated genotoxicity induced by inflammatory cytokines through activation of iNOS may be involved in the process of biliary carcinogenesis in response to chronic inflammation of the biliary tree. 展开更多
关键词 Biliary carcinoma Inflammation Inflammatory cytokine Nitric oxide Inducible nitric oxide synthase DNA damage Gallbladder epithelial cell HAMSTER
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TRANSFORMING GROWTH FACTOR-β1 AND SMAD4 SIGNALING PATHWAY DOWN-REGULATES RENAL EXTRACELLULAR MATRIX DEGRADATION IN DIABETIC RATS 被引量:19
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作者 Qin Yang Ru-jia Xie +4 位作者 Ting Yang Li Fang Bing Han Guo-zhong Zhang Ming-liang Cheng 《Chinese Medical Sciences Journal》 CAS CSCD 2007年第4期243-249,共7页
Objective To investigate the role of transforming growth factor-131 (TGF-β1)/Smad4 pathway in development of renal fibrosis in streptozotocin (STZ)-induced diabetic nephropathy (DN) rats and explore its possibl... Objective To investigate the role of transforming growth factor-131 (TGF-β1)/Smad4 pathway in development of renal fibrosis in streptozotocin (STZ)-induced diabetic nephropathy (DN) rats and explore its possible mechanism. Methods Male Wistar rats weighing 180-220 g were divided into 5 groups: group A ( normal control), group B [ diabetes mellitus (DM) 2 weeks ], group C ( DM 4 weeks), group D ( DM 8 weeks), and group E ( DM 16 weeks). Except for the normal control group, other groups were induced DM by single injection of STZ (55 mg/kg) respectively. Blood glucose level, serum creatinine, and 24-hour urine protein were examined. Expressions of TGF-β1 and Smad4 protein and mRNA in kidney were detected using immunohistochemical technique, Western blot, and real-time PCR. mRNA expressions of stromelysin-1 ( MMP-3 ), tissue inhibitor of metalloproteinase-1 ( TIMP-1 ), and collagen Ⅲ in kidney were also detected by real-time PCR. Results The levels of blood glucose, serum creatinine, and 24-hour urine protein in rats of group B, C, D, and E were higher than those of the control group. With the progression of renal fibrosis, the expressions of TGF-β1 and Smad4 protein and mRNA in kidney of diabetic rats elevated. In addition, the renal MMP-3 mRNA expression diminished in diabetic rats, while TIMP-1 and collagen Ⅲ mRNA increased. Conclusions In STZ-induced diabetic rats, the TGF-β1/Smad4 appears to play an important role in renal fibrosis of DN. The increased expression of TGF-β1 and Smad4 might result in the transcriptional regulation of downstream target genes of TGF-β1/Smad4 pathway, which contributes to the progression of renal fibrosis in diabetic rats. 展开更多
关键词 transforming growth factor-β1 SMAD4 diabetes mellitus renal fibrosis
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EXPRESSION AND LOCALIZATION OF SMAD4 PROTEIN IN RAT TESTIS DURING THE POSTNATAL DEVELOPMENT 被引量:2
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作者 张远强 胡静 +1 位作者 刘新平 许若军 《Chinese Medical Sciences Journal》 CAS CSCD 2003年第3期155-161,共7页
Objective.To study expression and localiza tion of Smad4protein,the common-mediator Smad,which is one of intracellular signaling molecules of transforming growth factor-afamily,in rat t estis during postnatal developm... Objective.To study expression and localiza tion of Smad4protein,the common-mediator Smad,which is one of intracellular signaling molecules of transforming growth factor-afamily,in rat t estis during postnatal development.Methods.In this study,whole testes were co llected from S.D rats aged3days,7days,14days and28days,and adult respe ctively.We examined the cellular localization and developmental change of Smad 4in rat testis by immunohistochemical ABC method with glucose oxidase-DAB-nic kel enhancement technique;the quantitative analysis of the immunostaining by t he image analysis system;the Smads pro-teins coexistence in the adult rat test is by the double immune staining for CD14-Smad4and Smad2-Smad4;the prote in expression of Smad during rat testicular development by means of Western blo ts.Results.The protein of Smad4was present in rats from3days of age to adul thood,and the im-munolocalization was exclusively localized to the cytoplasm o f Leydig cells with negative nuclei in the in-terstitial tissue at any time po int.No expression was detected in germ cells.The result of image and sta-tis tical analysis showed that generally,there was a tendency that the expression o f Smad4in the testes increased gradually with the rats developing maturation.C onclusion.Our data provide direct evidence for the molecular mechanism of TGF-aaction in rat testes during postnatal development and spermatogenesis of ra ts. 展开更多
关键词 tran sf orming growth factor SMAD4 TESTIS
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Expression of endothelial nitric oxide synthase and vascular endothelial growth factor in association with neovascularization in human primary astrocytoma 被引量:2
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作者 潘剑威 詹仁雅 +2 位作者 童鹰 周永庆 章明 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE EI CAS CSCD 2005年第7期693-698,共6页
Objective: To investigate the relationship between the expression of endothelial nitric oxide synthase (eNOS), vascular endothelial growth factor (VEGF) and angiogenesis in primary astrocytoma. Methods: Thirty-seven p... Objective: To investigate the relationship between the expression of endothelial nitric oxide synthase (eNOS), vascular endothelial growth factor (VEGF) and angiogenesis in primary astrocytoma. Methods: Thirty-seven primary astrocytomas and 4 astrocytic hyperplasia samples were collected and divided into three groups according to histological grade. The expression of eNOS, VEGF and factorⅧ related antigen (FⅧRAg) were assayed by immunohistochemistry. Microvascular density was assessed by FⅧRAg immunoreactivity. The intensity of immunoreactivity was graded according to the percentage of positive tumor cells. Results: No eNOS and VEGF were expressed in the astrocytes and vascular endothelium in astrocytic hyperplasia. The expression of eNOS or VEGF was light in low-grade astrocytoma and strong in glioblastoma. eNOS expression in astrocytoma was very positively correlated with VEGF. eNOS and VEGF expression in anaplastic astrocytoma was median in contrast to the low grade astrocytoma and glioblastoma. Lower microvascular density was found in low grade astrocytoma than that in higher grade malignant ones. The expressions of eNOS and VEGF were correlated with microvascular density and tumor malignancy. Conclusion: This finding suggests that eNOS and VEGF may have cooperative effect in tumor angiogenesis and play an important role in the pathogenesis of primary astrocytoma. 展开更多
关键词 Endothelial nitric oxide synthase Vascular endothelial growth factor Density of microvessels Primary astrocytoma
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Mass Transfer Enhancement of Propane Absorption into Dodecane-Water Emulsions 被引量:8
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作者 沈树华 马友光 +2 位作者 刘玮莅 卢素敏 朱春英 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第2期217-222,共6页
A one-dimensional unsteady heterogeneous parallel mass transfer(ODUHPMT) model was developed for the absorption enhancement of volatile organic compounds(VOC) by the dispersed droplets.An analytical solution for enhan... A one-dimensional unsteady heterogeneous parallel mass transfer(ODUHPMT) model was developed for the absorption enhancement of volatile organic compounds(VOC) by the dispersed droplets.An analytical solution for enhancement factor was obtained based on surface renewal theory and the Laplace domain transformation. The absorption rate of propane into water at different stirring speeds with the added micro dodecane droplets was investigated experimentally in a thermostatic stirred tank.The mass transfer flux across the gas-liquid interface and the enhancement factor were measured.The results showed that the dodecane has an obvious enhancement effect on propane absorption into water,the maximum enhancement factor reached 11.The enhancement factor increased with increasing dodecane volume fraction and decreased with increasing stirring speed.The experiment data agreed well with the model predictions and showed high prediction accuracy of ODUHPMT model. 展开更多
关键词 enhancement factor mass transfer ABSORPTION droplets
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Effects of penehyclidine hydrochloride in small intestinal damage caused by limb ischemia-reperfusion 被引量:25
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作者 Yan Zhang Yu-Fang Leng Xing Xue Yue Zhang Tao Wang Yu-Qing Kang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第2期254-259,共6页
AIM:To investigate the protective effect of penehyclidine hydrochloride post-conditioning in the damage to the barrier function of the small intestinal mucosa caused by limb ischemia-reperfusion(LIR) injury. METHODS:M... AIM:To investigate the protective effect of penehyclidine hydrochloride post-conditioning in the damage to the barrier function of the small intestinal mucosa caused by limb ischemia-reperfusion(LIR) injury. METHODS:Male Wistar rats were randomly divided into three groups(36 rats each) :the sham-operation group(group S) ,lower limb ischemia-reperfusion group(group LIR) ,and penehyclidine hydrochloride postconditioning group(group PHC) .Each group was divided into subgroups(n=6 in each group) according to ischemic-reperfusion time,i.e.immediately 0 h(T1) ,1 h(T2) ,3 h(T3) ,6 h(T4) ,12 h(T5) ,and 24 h(T6) .Bilateral hind-limb ischemia was induced by rubber band application proximal to the level of the greater trochanter for 3 h.In group PHC,0.15 mg/kg of penehyclidine hydrochloride was injected into the tail vein immediately after 3 h of bilateral hind-limb ischemia.The designated rats were sacrificed at different time-points of reperfusion;diamine oxidase(DAO) ,superoxide dismutase(SOD) activity,myeloperoxidase(MPO) of small intestinal tissue,plasma endotoxin,DAO,tumor necrosis factor-α(TNF-α) ,and interleukin(IL) -10 in serum were detected in the rats. RESULTS:The pathological changes in the small intestine were observed under light microscope.The levels of MPO,endotoxin,serum DAO,and IL-10 at T1-T6,and TNF-αlevel at T1-T4 increased in groups LIR and PHC(P<0.05) compared with those in group S,but tissue DAO and SOD activity at T1-T6 decreased(P<0.05) .In group PHC,the tissue DAO and SOD activity at T2-T6,and IL-10 at T2-T5 increased to higher levels than those in group LIR(P<0.05) ;however,the levels of MPO,endotoxin,and DAO in the blood at T2-T6,and TNF-αat T2 and T4 decreased(P<0.05) . CONCLUSION:Penehyclidine hydrochloride post-conditioning may reduce the permeability of the small intestines after LIR.Its protection mechanisms may be related to inhibiting oxygen free radicals and inflammatory cytokines for organ damage. 展开更多
关键词 Penehyelidine hydrochloride POST-CONDITIONING Limb ischemia-reperfusion injury Small intestine PROTECTION
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Effect of Salinity on the Biosynthesis of Amines in Litopenaeus vannamei and the Expression of Gill Related Ion Transporter Genes 被引量:5
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作者 PAN Luqing LIU Hongyu ZHAO Qun 《Journal of Ocean University of China》 SCIE CAS 2014年第3期453-459,共7页
This study examined the effect of salinity on the expression of Na+/K+-ATPase(NKA) α-subunit and vacuolar-type H+-ATPase(V-ATPase) β-subunit gene in the gill of Litopenaeus vannamei. Semi-quantitative reverse transc... This study examined the effect of salinity on the expression of Na+/K+-ATPase(NKA) α-subunit and vacuolar-type H+-ATPase(V-ATPase) β-subunit gene in the gill of Litopenaeus vannamei. Semi-quantitative reverse transcription-polymerase chain reaction(RT-PCR) assay showed that the expression of NKA α-subunit and V-ATPase β-subunit gene was significantly influenced by salinity. It was found that the NKA activity significantly varied with salinity in time and dose dependent manner; whereas the V-ATPase activity did not. The abundance of NKA α-subunit gene transcript increased rapidly when the salinity decreased from 26 b to 21, and slowly when the salinity decreased from 26 to 31 within the first 24 h. When the salinity decreased from 26 to 21, the transcription of NKA α-subunit gene in gill epithelium was higher at 12 h than that at 0 h, which was consistent with the result of immunoblotting assay of NKA α-subunit. In addition, salinity had a significant time- and dose-dependent effect on the concentration of biogenic amines in both hemolymph and gill. As compared to other parameters, the concentration of dopamine(DA) and 5-hydroxytryptamine(5-HT) varied in different patterns when the salinity decreased from 26 to 21 or increased from 26 to 31, suggesting that DA and 5-HT played different regulatory roles in osmotic adaption and modulation of shrimp when salinity varies. 展开更多
关键词 SALINITY Litopenaeus vannamei biogenic amine Na^+/K^+-ATPase V-ATPASE
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C-reactive protein,procalcitonin,interleukin-6,vascular endothelial growth factor and oxidative metabolites in diagnosis of infection and staging in patients with gastric cancer 被引量:18
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作者 NevinIlhan NecipIlhan +2 位作者 MehmetKcksu Yavuz Ilhan Handan Akbulut 《World Journal of Gastroenterology》 SCIE CAS CSCD 2004年第8期1115-1120,共6页
AIM:The current study was to determine the serum/pLasma levels of VEGF,IL-6,malondialdehyde (MDA),nitric oxide (NO),PCT and CRP in gastric carcinoma and correlation with the stages of the disease and accompanying infe... AIM:The current study was to determine the serum/pLasma levels of VEGF,IL-6,malondialdehyde (MDA),nitric oxide (NO),PCT and CRP in gastric carcinoma and correlation with the stages of the disease and accompanying infection. METHODS:We examined the levels of serum VEGF,IL-6, PCT,CRP and plasma MDA,NO in 42 preoperative gastric cancer patients and 23 healthy subjects.There were infection anamneses that had no definite origin in 19 cancer patients. RESULTS:The VEGF levels (mean±SD; pg/mL) were 478.05±178.29 and 473.85±131.24 in gastric cancer patients with and without infection,respectively,and these values were not significantly different (P>0.05).The levels of VEGF, CRP,PCT,It-6,MDA and NO in cancer patients were significantly higher than those in healthy controls and the levels of CRP,PCT,It-6,MDA and NO were statistically increased in infection group when compared with non- infection group (P<0.001). CONCLUSION:Although serum VEGF concentrations were increased in gastric cancer,this increase might not be related to infection.CRP,PCT,IL-6,MDA and NO have obvious drawbacks in the diagnosis of infections in cancer patients. These markers may not help to identify infections in the primary evaluation of cancer patients and hence to avoid unnecessary antibiotic treatments as well as hospitalization. According to the results of this study,IL-6,MDA,NO and especially VEGF can be used as useful parameters to diagnose and grade gastric cancer. 展开更多
关键词 Abdominal Pain Aged Biological Markers C-Reactive Protein CALCITONIN Female Helicobacter Infections Humans INTERLEUKIN-6 Male MALNUTRITION MALONDIALDEHYDE Middle Aged Neoplasm Staging Nitric Oxide Oxidative Stress Protein Precursors Stomach Neoplasms Tumor Markers Biological Vascular Endothelial Growth Factor A VOMITING Weight Loss
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Effects of transforming growth interacting factor on biological behaviors of gastric carcinoma cells 被引量:9
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作者 Zhong-LiangHu Ji-Fangwen De-ShengXiao HuiZhen Chun-YanFu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第1期84-88,共5页
AIM:Transforming growth interacting factor (TGIF) is an inhibitor of both transforming growth factor β (TGF-β) and retinoid signaling pathways. Moreover, the activation of MAPK pathway can prolong its half-life. How... AIM:Transforming growth interacting factor (TGIF) is an inhibitor of both transforming growth factor β (TGF-β) and retinoid signaling pathways. Moreover, the activation of MAPK pathway can prolong its half-life. However, its role in carcinogenesis is still unknown. Thus we attempted to investigate the effect of TGIF on biologic behaviors of gastric carcinoma cells.METHODS: Gastric carcinoma cell line, SGC-7901, was stably transfected with plasmid PcDNA3.1-TGIF. Western blotting and cell immunohistochemistry screening for the highly expressing clone of TGIF were employed. The growth of transfected cells was investigated by MTT and colonyformation assays, and apoptosis was measured by flow cytometry (FCM) and transmission electron microscopy.Tumorigenicity of the transfectant cells was also analyzed.RESULTS: TGIF had no effect on the proliferation, cell cycle and apoptosis of SGC-7901 cells, but cellular organelles of cells transfected with TGIF were richer than those of vector control or parental cells. Its clones were smaller than the control ones in plate efficiency, and its tumor tissues also had no obvious necrosis compared with the vector control or parental cells. Moreover, TGIF could resist TGF-β mediated growth inhibition.CONCLUSION: TGIF may induce differentiation of stomach neoplastic cells. In addition, TGIF can counteract the growth inhibition induced by TGF-β. 展开更多
关键词 Gastric carcinoma TG interacting factor Cell differentiation TGF-BETA
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Clinical benefits of biochemical markers of bone turnover in Egyptian children with chronic liver diseases 被引量:3
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作者 Karam A Mahdy Hanaa H Ahmed +1 位作者 Fathia Mannaa Azza Abdel-Shaheed 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第5期785-790,共6页
AIM: To investigate the association between serum insulin-like growth factor 1 (IGF-1), osteocalcin, and parathyroid hormone (PTH) levels with the etiology and clinical condition of patients with chronic liver di... AIM: To investigate the association between serum insulin-like growth factor 1 (IGF-1), osteocalcin, and parathyroid hormone (PTH) levels with the etiology and clinical condition of patients with chronic liver disease. METHODS: Eighty children with hepatocellular damage were divided into 3 groups according to the etiology of disease infection: bilharziasis (9 patients), hepatitis B virus (HBV, 12 patients) and hepatitis C virus (HCV, 29 patients). The Child score index was found as A in 24 patients, B in 22 patients, C in 4 patients. Thirty healthy children served as control group.HBsAg, HBcAbIgM, HBcAbIgG, and anti-HCV were detected using ELISA technique. HCV-RNA was measured by reverse transcription polymerase chain reaction (RT-PCR). Antibllharzial antibodies were detected by indirect haemagglutination test. Liver function tests were performed using autoanalyser. Serum IGF-1, osteocalcin and PTH levels were measured by ELISA technique. Abdominal ultrasonography was also conducted. RESULTS: Serum IGF-1 level was significantly lower in all patient groups with liver diseases, while serum osteocalcin and PTH levels were significantly elevated in patients with HBV and HCV infections compared with the control group. Serum osteocalcin and PTH concentrations were measured with the severity of liver disease from Child A to C. Child A patients unexpectedly showed significantly reduced IGF-1 levels in comparison to patients staged as Child B or C. Serum osteocalcin level was negatively correlated with albumin (14.7 ± 0.54 vs 3.6 ± 0.10, P 〈 0.05), while that for PTH was positively correlated with total protein (70.1 ± 2.17 vs 6.7 ± 0.10, P 〈 0.05) in patients with HCV infection. 展开更多
关键词 Liver disease Bone turnover Insulin-like growth factor-1 OSTEOCALCIN Parathyroid hormone
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