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基于多任务学习的同行评审细粒度情感分析模型 被引量:1
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作者 朱金秋 檀健 +1 位作者 韩斌彬 殷秀秀 《中北大学学报(自然科学版)》 CAS 2024年第1期105-113,共9页
学术论文同行评审能够直接反映审稿人对论文的主观评价,对审稿文本进行情感分析有利于挖掘审稿人对论文多维度的评价信息。现有的情感分析模型仅能挖掘专家单一的评审维度和相应的情感倾向,本文提出了一种基于多任务学习的同行评审细粒... 学术论文同行评审能够直接反映审稿人对论文的主观评价,对审稿文本进行情感分析有利于挖掘审稿人对论文多维度的评价信息。现有的情感分析模型仅能挖掘专家单一的评审维度和相应的情感倾向,本文提出了一种基于多任务学习的同行评审细粒度情感分析模型。该模型在多任务学习框架下,通过在BERT-LCF模型的基础上增加BiLSTM-CRF模块,使其具备了同时完成属性词抽取和细粒度情感分析任务的能力。与传统的基于Pipeline模式的单任务细粒度情感分析模型相比,本模型在保证精度的情况下可以同时完成评审属性提取和情感分析任务。在这两项任务中,所提出模型的F1分数分别达到了89.01%和90.71%。对比实验证明,在多任务场景下,引入BiLSTM-CRF模块对评审文本属性词提取任务有一定的提升作用。 展开更多
关键词 同行评审 多任务学习 属性词抽取 粒度情分析 BiLSTM-CRF
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二维超声、超声造影及细针穿刺针感赋值评分在TI-RADS 3~4级甲状腺微小结节鉴别诊断中的应用 被引量:18
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作者 张隽 陈辽 +4 位作者 胡伟 孙彬 黄鑫 黄星月 陈文卫 《临床超声医学杂志》 2018年第3期161-164,共4页
目的探讨二维超声、超声造影及超声引导下细针穿刺(US-FNA)针感赋值评分在甲状腺影像报告和数据系统(TI-RADS)3~4级甲状腺微小结节鉴别诊断中的应用价值。方法选取我院经病理证实的TI-RADS 3~4级甲状腺微小结节患者149例(共计149个结节)... 目的探讨二维超声、超声造影及超声引导下细针穿刺(US-FNA)针感赋值评分在甲状腺影像报告和数据系统(TI-RADS)3~4级甲状腺微小结节鉴别诊断中的应用价值。方法选取我院经病理证实的TI-RADS 3~4级甲状腺微小结节患者149例(共计149个结节),其中良性结节87个,恶性结节62个。比较良恶性结节的二维超声特征、超声造影特征及US-FNA针感情况;ROC曲线分析单独及联合赋值评分诊断恶性结节的相应截断值,并计算其诊断效能。结果良、恶性微小结节的二维超声征象即形态不规则、极低回声及低回声、微钙化及粗钙化、纵横比、声晕、声衰减比较差异均有统计学意义(均P<0.05);良、恶性微小结节的超声造影特征即增强模式、增强类型及增强速度比较差异均有统计学意义(均P<0.05);良、恶性微小结节的US-FNA针感比较差异有统计学意义(P<0.05)。二维超声、超声造影及USFNA针感两两联合赋值评分对甲状腺恶性微小结节的诊断准确率均可达80%以上,三者联合赋值评分诊断甲状腺恶性微小结节的敏感性最高(90.3%),其中超声造影、US-FNA联合赋值评分诊断的敏感性、特异性及准确率均可达80%以上(分别为80.6%、83.9%及82.3%)。结论对二维超声、超声造影及US-FNA相关指标进行联合赋值评分,可以提高TIRADS 3~4级甲状腺微小结节的诊断水平。 展开更多
关键词 声检查 造影剂 微小结节 甲状腺 甲状腺影像报告和数据系统 针穿刺针
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Investigation on the Sterility Changeover of Male Sterility Line CMS7311 in Heading Chinese Cabbage 被引量:12
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作者 张鲁刚 郝东方 《Acta Botanica Sinica》 CSCD 2001年第11期1123-1128,共6页
Sterility changeover induced by low temperature in male sterility line CMS7311 of heading Chinese cabbage ( Brassica campestris L. ssp. penkinsis) was investigated under constant temperature, day/night alternating tem... Sterility changeover induced by low temperature in male sterility line CMS7311 of heading Chinese cabbage ( Brassica campestris L. ssp. penkinsis) was investigated under constant temperature, day/night alternating temperature in light-growth-incubator and outdoor natural day/night alternating temperature respectively. It showed that the sterility of CMS7311 has significant change with temperature. The constant temperature of 6 - 12 degreesC was suitable to induce the changeover of sterility (CGS) of CMS7311 ; the shortest treatment time for CGS induction at this temperature was 3 d. The significant value of sterility changeover of CMS7311 occurred at the constant temperature of 6 - 9 degreesC after treatment for 6 - 9 d. The intensity of CGS was stronger under constant temperature than under alternate temperature, but the shortest treatment time inducing CGS has no difference between them. When treated for 9 d under the day/night alternating temperature of 11/7 degreesC, its sterility could also turn to normal fertility (near to sterile grade I or zero). In normal condition, the interval from the end of temperature treatment to the beginning of CGS induction was 10 - 16 d. In the condition of natural day/night alternating temperature, the lower limit of temperature for effective CGS induction was at the daily mean temperature ( DMT) of 3. 5 - 6. 8 degreesC, and the shortest treatment time which could induce the sterility changeover was also longer than that under constant temperature, being 11d at DMT of 1.5 - 3.1 degreesC. In addition, for the apical dominance, the flower bud on the first lateral branch showed the CGS 8 - 10 d later than the flower bud on the main stem under the same temperature with the same days of treatment. The intensity of CGS of CMS7311 on the first lateral branch was also weaker than the flower bud on the main stem. 展开更多
关键词 heading Chinese cabbage CMS7311 changeover of sterility (CGS) temperature sensitive
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Effects of the Ice Bath Time after Heat Shock and the Incubation Time on the Efficiency of Chemical Transformation Method 被引量:2
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作者 郭姣洁 薛永常 +2 位作者 薛张伟 徐书景 鞠建松 《Agricultural Science & Technology》 CAS 2010年第9期198-200,共3页
[Objective] The aim of the research was to study the effect of the ice bath time after heat shock and the incubation time on the transformation efficacy,and to establish a simple and quick transformation method.[Metho... [Objective] The aim of the research was to study the effect of the ice bath time after heat shock and the incubation time on the transformation efficacy,and to establish a simple and quick transformation method.[Method]Competent cells were prepared with two buffer solutions;with the ice bath time after heat shock and the recovery time as the variables,the relationship between these two factors and transformation efficacy was studied.[Result]The transformation efficacy was the best when the ice bath time was 2 min and the recovery time was 30 or 40 min;when the ice bath time and the recovery time was 0 min,a certain amount of transformants still could be obtained.[Conclusion]The ice bath time after heat shock and the recovery time had certain impact on transformation efficacy,but they were not the decisive factors.Therefore,in the general transformation experiment,these two steps could be omitted. 展开更多
关键词 Competent cell Transformation efficiency Ice bath time Recovery time
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The Effect of Helicobacter Pylori Infection on Expression of hMSH2, hMLH1 and p53 in Gastric Carcinogenesis 被引量:2
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作者 马坚妹 范凯 +5 位作者 胡少为 王朝晖 刘敏 吕申 刘丽娜 许国旺 《The Chinese-German Journal of Clinical Oncology》 CAS 2005年第4期209-212,共4页
Objective: To detect the expression of hMSH2, hMLH1 and p53 in gastric epithelial cells with and without Helicobactcr pylori (H. pylori) infection and investigate the relationship between H. pylori infection and th... Objective: To detect the expression of hMSH2, hMLH1 and p53 in gastric epithelial cells with and without Helicobactcr pylori (H. pylori) infection and investigate the relationship between H. pylori infection and these genes in gastric carcinogenesis. Methods: H. pylori infection was detected by rapid urease tests. Expression of hMSH2, hMLHland p53 in gastric cancer (GC) tissue, its adjacent mucosa, gastritic mucosa and normal mucosa was assessed by immunohistochemistry SP method. Results: Positive expression rate of hMSH2 in GC tissue (62.7%) was higher than those in adjacent mucosa (29.4%), gastritic mucosa (32.4%) and normal mucosa (30.0%) (P〈0.001). Positive rate of hMSH2 in poorly differentiated adenocarcinoma (76.4%) was higher than those in other carcinomas (54.3%, 53.1%) (P〈0.05). Positive expression rate of hMLH1 in GC tissue (64.3%) mucosa (82.4%) and normal mucosa (80.0%) was lower than those in adjacent mucosa (84.4%), gastritic (P〈0.01). Positive rate of hMLH1 in mucoid carcinoma (43.7%) was lower than those in other carcinomas (78.2%, 64.7%) (P〈0.01). Positive expression rate of p53 in GC tissue (51.9%) was higher than those in adjacent mucosa (3.1%), gastritic mucosa (0.0%) and normal mucosa (0.0%) (P〈0.001). Positive rate of p53 in well differentiated adenocarcinoma (32.6%) was lower than those in other carcinomas (58.8%, 68.7%) (P〈0.01). Positive rates of hMSH2 and hMLH1 in GC with H. pylori infection were lower than those without the infection, respectively (P〈0.05). Positive rate of p53 in GC with H. pylori infection (61.4%) was higher than that without the infection (40.6%) (P〈0.05). Conclusion: Gastric carcinogenesis may be associated with abnormal expression of hMSH2, hMLH1 and p53; H. pylori infection affecting expression of these genes may be one of its carcinogenic mechanisms. 展开更多
关键词 Helicobacter pylori gastric cancer HMSH2 HMLH1 P53 IMMUNOHISTOCHEMISTRY
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Bacterial infections in cirrhotic patients with hepatocellular carcinoma
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作者 肖小炜 周亚杰 郭奉云 《World Journal of Gastroenterology》 SCIE CAS CSCD 1996年第1期22-24,共3页
AIMS To establish the prevalence of bacterial infection in cir- rhotic patients with hepatocellular carcinoma(HCC). METHODS All 719 cirrhotic patients with HCC were investigat- ed retrospectively for the prevalence of... AIMS To establish the prevalence of bacterial infection in cir- rhotic patients with hepatocellular carcinoma(HCC). METHODS All 719 cirrhotic patients with HCC were investigat- ed retrospectively for the prevalence of bacterial infections. RESULTS The incidence of bacterial infection was 15.4% (111/719).According to Child-Pugh classification,the inci- dences of bacterial infection in class A,B and C were 2.3%,8. 0%,and 26.4 %,respectively.The bacterial infection increased with the severity of cirrhosis and severe bacterial infections usual- ly occurred in Child-Pugh class B and C patients. CONCLUSIONS The susceptibility of HCC patients to bacterial infection is mainly due to the underlying cirrhosis and not to the HCC itself. 展开更多
关键词 liver cirrhosis liver neoplasms bacterial infection carcinoma hepatocellular
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Decreased contrast sensitivity of visual cortical cells to visual stimuli accompanies a reduction of intracortical inhibition in old cats 被引量:2
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作者 周俊 施夏明 +2 位作者 彭青松 化国鹏 华田苗 《Zoological Research》 CAS CSCD 北大核心 2011年第5期533-539,共7页
Psychophysical experiments on human and animal subjects have proven that aged individuals show significantly reduced visual contrast sensitivity compared with young adults.To uncover the possible neural mechanisms,we ... Psychophysical experiments on human and animal subjects have proven that aged individuals show significantly reduced visual contrast sensitivity compared with young adults.To uncover the possible neural mechanisms,we used extracellular single-unit recording techniques to examine the response of V1(primary visual cortex) neurons as a function of visual stimulus contrast in both old and young adult cats(Felis catus).The mean contrast sensitivity of V1 neurons to visual stimuli in old cats decreased significantly relative to young adult cats,consistent with findings reported in old primates.These results indicate that aging can affect contrast sensitivity of visual cortical cells in both primate and non-primate mammalian animals,and might contribute to the reduction of perceptual visual contrast sensitivity in aged individuals.Further,V1 cells of old cats exhibited increased responsiveness,decreased signal-to-noise ratio,and enlarged receptive field(RF) size compared with that of young adult cats,which indicated that decreased contrast sensitivity of V1 neurons accompanied a reduction of intracortical inhibition during senescence. 展开更多
关键词 Contrast sensitivity V1 neurons Old cats Young adult cats
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Effects of C_6-HSL on Potato Growth and Capacity against Soft Rot Disease 被引量:3
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作者 黄媛媛 邱健 +3 位作者 马宏 苏浴源 宋聪 宋水山 《Agricultural Science & Technology》 CAS 2010年第1期61-64,共4页
[Objective]The aim of this study was to investigate whether communication signal C6-HSL among individual bacteria can influence plant growth and disease resistance ability. [Method]With potato virus-free plantlets as ... [Objective]The aim of this study was to investigate whether communication signal C6-HSL among individual bacteria can influence plant growth and disease resistance ability. [Method]With potato virus-free plantlets as the test materials and C6-HSL as the inducer,the potato's growth and the ability of resistance against Erwinia carotovora subp carotovora were tested after being treated by C6-HSL with different concentrations. The effects of C6-HSL on plant landmark defense enzyme activities and H2O2 content in potato leaves were measured especially. [Result]C6-HSL with different concentrations could obviously inhibit the growth rate of root and the number of roots,but had no effect on plant height,number of nodes and leaf size. POD or SOD activity and H2O2 content in plant landmark defense enzymes significantly increased after induction of C6-HSL,but PAL and PPO activity had no obvious change. In the resistant test,potato plants induced by C6-HSL could inhibit the infection of Erwinia carotovora subp carotovora effectively,and its incidence was significantly lower than the control group. [Conclusion]Bacteria AHL can be possibly used as a new kind of plant disease-resistant activator. 展开更多
关键词 Bacterial quorum sensing signal molecule C6-HSL POTATO Defense enzyme Erwinia carotovora subp carotovora
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Cultural and luminescent Conditions of a Marine luminous Bacterium
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作者 方宏达 董燕红 +2 位作者 袁茵 李秀芹 易斌 《Marine Science Bulletin》 CAS 2008年第1期46-53,共8页
Study of marine noctilucence in marine is important to fishery, environmental monitoring and military affairs. A luminous bacterial strain D2 was isolated from the marine sediment samples collected near Donghai Island... Study of marine noctilucence in marine is important to fishery, environmental monitoring and military affairs. A luminous bacterial strain D2 was isolated from the marine sediment samples collected near Donghai Island in Zhanjiang, China. The primary cultural and luminescent conditions of luminous bacterium D2 which was identified as Vibrio sp. were determined in liquid culture. The results showed that pH 7.0, 35 ℃, with 2.0 % NaCI, were the best growth conditions, and pH5 - 6, 20℃, OD600 0.08, with 3.0 % NaCI, were the optimal luminescent conditions. 展开更多
关键词 Luminous bacterium growth conditions luminescent conditions quorum sensing system
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Inhibition of Telomerase with hTERT Antisense Increases Susceptibility of Leukemic Cells to CDDP-induced Apoptosis 被引量:1
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作者 张洹 何冬梅 《The Chinese-German Journal of Clinical Oncology》 CAS 2004年第1期42-46,67,共6页
Objective: To investigated the e?ect of inhibition of telomerase with hTERT antisense on leukemic cells (HL-60 and K562) to CDDP-induced apoptosis. Methods: Antisense phosphorothioate oligodeox... Objective: To investigated the e?ect of inhibition of telomerase with hTERT antisense on leukemic cells (HL-60 and K562) to CDDP-induced apoptosis. Methods: Antisense phosphorothioate oligodeoxynucleotide (AS PS-ODN) was synthesized and puri?ed. Telomerase activity was detected by Telomerase PCR ELASA kit and cell apoptosis was observed by morphological method and determined by ?owcytometry. Results: AS PS-ODN could signi?cantly inhibit telomerase activity by down regulat- ing the hTERT expression, and increase the susceptibility of leukemic cells to CDDP-induced apoptosis. Conclusion: Inhibition of telomerase with hTERT antisense can increases the susceptibility of leukemic cells to CDDP-induced apoptosis. 展开更多
关键词 human telomerase reverse transcriptase Antisense phosphorothioate oligodeoxynucleotide TELOMERASE leukemic cells cis-diamminedichloroplatinum
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Is the Potential Interconnection between Antibiotic Susceptibility and Disinfectant Resistance a Threat to Food Safety?
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作者 周倩 唐梦君 +6 位作者 张静 张小燕 唐修君 陈大伟 顾荣 陆俊贤 高玉时 《Agricultural Science & Technology》 CAS 2017年第6期1033-1037,共5页
The prevalence of antibiotic susceptibility and disinfectant resistance in bacterial pathogens causes a serious problem not only to food safety but also to public health, which directly or indirectly leads to treatmen... The prevalence of antibiotic susceptibility and disinfectant resistance in bacterial pathogens causes a serious problem not only to food safety but also to public health, which directly or indirectly leads to treatment and disinfection failures. In this review, multidrug resistance, the mechanism of disinfectant resistance, the methods for detecting disinfectant resistance and the cross-resistance between an- tibiotics and disinfectants are summarized. More efforts should be devoted to explor- ing the professional guidance of using antibiotics and disinfectants, and to develop- ing the comprehensive detection with genetic and molecular methods is highly ex- pected. 展开更多
关键词 Food safety BACTERIA Antibiotic susceptibility Disinfectant resistance
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Helicobacter pylori eradication to prevent gastric cancer: underlying molecular and cellular mechanisms 被引量:7
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作者 Shingo Tsuji Masahiko Tsujii +7 位作者 Hiroaki Murata Tsutomu Nishida Masato Komori Masakazu Yasumaru Shuji Ishii Yoshiaki Sasayama Sunao Kawano Norio Hayashi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第11期1671-1680,共10页
Numerous cellular and molecular events have been described in development of gastric cancer. In this artide, we overviewed roles of Helicobacter pylori (H pylori) infection on some of the important events in gastric... Numerous cellular and molecular events have been described in development of gastric cancer. In this artide, we overviewed roles of Helicobacter pylori (H pylori) infection on some of the important events in gastric carcinogenesis and discussed whether these cellular and molecular events are reversible after cure of the infection. There are several bacterial components affecting gastric epithelial kinetics and promotion of gastric carcinogenesis. The bacterium also increases risks of genetic instability and mutations due to NO and other reactive oxygen species. Epigenetic silencing of tumor suppressor genes such as RUNX3 may alter the frequency of phenotype change of gastric glands to those with intestinal metaplasia. Host factors such as increased expression of growth factors, cytokines and COX-2 have been also reported in non-cancerous tissue in Hpylori-positive subjects. It is noteworthy that most of the above phenomena are reversed after the cure of the infection. However, some of them including overexpression of COX-2 continue to exist and may increase risks for carcinogenesis in metaplastic or dysplastic mucosa even after successful H pylori eradication. Thus, H pylori eradication may not completely abolish the risk for gastric carcinogenesis. Efficiency of the cure of the infection in suppressing gastric cancer depends on the timing and the target population, and warrant further investigation. 展开更多
关键词 HELICOBACTER Cancer Gastric acid p53 INFLAMMATION Gastric atrophy Intestinal metaplasia
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Hepatitis C virus infection and apoptosis 被引量:10
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作者 Richard Fischer Thomas Baumert Hubert E Blum 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第36期4865-4872,共8页
Apoptosis is central for the control and elimination of viral infections. In chronic hepatitis C virus (HCV) infection, enhanced hepatocyte apoptosis and upregulation of the death inducing ligands CD95/Fas, TRAIL and ... Apoptosis is central for the control and elimination of viral infections. In chronic hepatitis C virus (HCV) infection, enhanced hepatocyte apoptosis and upregulation of the death inducing ligands CD95/Fas, TRAIL and TNFα occur. Nevertheless, HCV infection persists in the majority of patients. The impact of apoptosis in chronic HCV infection is not well understood. It may be harmful by triggering liver fibrosis, or essential in interferon (IFN) induced HCV elimination. For virtually all HCV proteins, pro- and anti-apoptotic effects have been described, especially for the core and NS5A protein. To date, it is not known which HCV protein affects apoptosis in vivo and whether the infectious virions act pro- or anti- apoptotic. With the availability of an infectious tissue culture system, we now can address pathophysiologically relevant issues. This review focuses on the effect of HCV infection and different HCV proteins on apoptosis and of the corresponding signaling cascades. 展开更多
关键词 Hepatitis C Spoptosis TRAIL CD95/Fas TNFΑ PERFORIN
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The host type I interferon response to viral and bacterial infections 被引量:12
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作者 AndreaK.PERRY GangCHEN +2 位作者 DahaiZHENG HongTANG GenhongCHENG 《Cell Research》 SCIE CAS CSCD 2005年第6期407-422,共16页
Type I interferons (IFN) are well studied cytokines with anti-viral and immune-modulating functions. Type I IFNsare produced following viral infections, but until recently, the mechanisms of viral recognition leading ... Type I interferons (IFN) are well studied cytokines with anti-viral and immune-modulating functions. Type I IFNsare produced following viral infections, but until recently, the mechanisms of viral recognition leading to IFN productionwere largely unknown. Toll like receptors (TLRs) have emerged as key transducers of type I IFN during viral infectionsby recognizing various viral components. Furthermore, much progress has been made in defining the signaling path-ways downstream of TLRs for type I IFN production. TLR7 and TLR9 have become apparent as universally importantin inducing type I IFN during infection with most viruses, particularly by plasmacytoid dendritic cells. New intracellularviral pattern recognition receptors leading to type I IFN production have been identified. Many bacteria can also inducethe up-regulation of these cytokines. Interestingly, recent studies have found a detrimental effect on host cells if type IIFN is produced during infection with the intracellular gram-positive bacterial pathogen, Listeria monocytogenes. Thisreview will discuss the recent advances made in defining the signaling pathways leading to type I IFN production. 展开更多
关键词 type I interferons Toll-like receptors pattern-recognition receptors virus infections Listeria monocytogenes signaling mechanisms.
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Roscovitine sensitizes breast cancer cells to TRAIL-induced apoptosis through a pleiotropic mechanism 被引量:5
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作者 Gustavo Ortiz-Ferrón Rosario Yerbes +3 位作者 Adriana Eramo Ana I López-Pérez Ruggero De Maria Abelardo Lápez-Rivas 《Cell Research》 SCIE CAS CSCD 2008年第6期664-676,共13页
The tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL/APO2L) is a member of the TNF gene superfamily that induces apoptosis upon engagement of cognate death receptors. While TRAIL is relatively ... The tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL/APO2L) is a member of the TNF gene superfamily that induces apoptosis upon engagement of cognate death receptors. While TRAIL is relatively non-toxic to normal cells, it selectively induces apoptosis in many transformed cells. Nevertheless, breast tumor cells are particularly resistant to the effects of TRAIL. Here we report that, in combination with the cyclin-dependent kinase inhibitor roscovitine, exposure to TRAIL induced marked apoptosis in the majority of TRAIL-resistant breast cancer cell lines examined. Roscovitine facilitated TRAIL death-inducing signaling complex formation and the activation of caspase-8. The cFLIPL and cFLIPs FLICE-inhibitory proteins were significantly down-regulated following exposure to roscovitine and, indeed, the knockdown of cFLIP isoforms by siRNA sensitized breast tumor cells to TRAIL-induced apoptosis. In addition, we demonstrate that roscovitine strongly suppressed Mcl-1 expression and up-regulated E2F1 protein levels in breast tumor ceils. Significantly, the silencing of Mci-1 by siRNA sensitized breast tumor cells to TRAIL-induced apoptosis. Furthermore, the knockdown of E2F1 protein by siRNA reduced the sensitizing effect of roscovitine in TRAIL-induced apoptosis. In summary, our results reveal a pleitropic mechanism for the pro-apoptotic influence of roscovitine, highlighting its potential as an antitumor agent in breast cancer in combination with TRAIL. 展开更多
关键词 apoptosis ROSCOVITINE CDK TRAIL DISC FLIP MCL-1 E2F1
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Melatonin reduces bacterial translocation and apoptosis in trinitrobenzene sulphonic acid-induced colitis of rats 被引量:5
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作者 Alper Akcan Can Kucuk +5 位作者 Erdogan Sozuer Duygu Esel Hizir Akyildiz Hulya Akgun Sabahattin Muhtaroglu Yucel Aritas 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第6期918-924,共7页
AIM: To investigate the effects of exogenous melatonin on bacterial translocation and apoptosis in a rat ulcerati-ve colitis model. METHODS: Rats were randomly assigned to three groups: groupⅠ: control, group Ⅱ: exp... AIM: To investigate the effects of exogenous melatonin on bacterial translocation and apoptosis in a rat ulcerati-ve colitis model. METHODS: Rats were randomly assigned to three groups: groupⅠ: control, group Ⅱ: experimental colitis, group Ⅲ: colitis plus melatonin treatment. On d 11 after colitis, plasma tumor necrosis factor-α, portal blood endotoxin levels, colon tissue myeloperoxidase and caspase-3 activity were measured. Bacterial translocation was quantified by blood, lymph node, liver and spleen culture. RESULTS: We observed a significantly reduced inciden-ce of bacterial translocation to the liver, spleen, mesen-teric lymph nodes, portal and systemic blood in animals treated with melatonin. Treatment with melatonin signifi-cantly decreased the caspase-3 activity in colonic tissues compared to that in trinitrobenzene sulphonic acid-trea-ted rats (16.11 ± 2.46 vs 32.97 ± 3.91, P < 0.01). CONCLUSION: Melatonin has a protective effect on ba-cterial translocation and apoptosis. 展开更多
关键词 MELATONIN COLITIS Bacterial translocation APOPTOSIS
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Pathophysiology of increased intestinal permeability in obstructive jaundice 被引量:49
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作者 Stelios F Assimakopoulos Chrisoula D Scopa Constantine E Vagianos 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第48期6458-6464,共7页
Despite advances in preoperative evaluation and postoperative care, intervention, especially surgery, for relief of obstructive jaundice still carries high morbidity and mortality rates, mainly due to sepsis and renal... Despite advances in preoperative evaluation and postoperative care, intervention, especially surgery, for relief of obstructive jaundice still carries high morbidity and mortality rates, mainly due to sepsis and renal dysfunction. The key event in the pathophysiology of obstructive jaundice-associated complications is endotoxemia of gut origin because of intestinal barrier failure. This breakage of the gut barrier in obstructive jaundice is multi-factorial, involving disruption of the immunologic, biological and mechanical barrier. Experimental and clinical studies have shown that obstructive jaundice results in increased intestinal permeability. The mechanisms implicated in this phenomenon remain unresolved, but growing research interest during the last decade has shed light in our knowledge in the field. This review summarizes the current concepts in the pathophysiology of obstructive jaundice-induced gut barrier dysfunction, analyzing pivotal factors, such as altered intestinal tight junctions expression, oxidative stress and imbalance of enterocyte proliferation and apoptosis. Clinicians handling patients with obstructive jaundice should not neglect protecting the intestinal barrier function before, during and after intervention for the relief of this condition, which may improve their patients’ outcome. 展开更多
关键词 Obstructive jaundice Intestinal barrier Intestinal permeability ENDOTOXEMIA Bacterial translocation Tight junctions OCCLUDIN CLAUDIN-4 Apoptosis Oxidative stress
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Effects of glucocorticoids on the growth and chemosensitivity of carcinoma cells are heterogeneous and require high concentration of functional glucocorticoid receptors 被引量:3
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作者 Yen-Shen Lu Huang-Chun Lien +4 位作者 Pei-Yen Yeh Kun-Huei Yeh Min-Liang Kuo Sung-Hsin Kuo Ann-Lii Cheng 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第40期6373-6380,共8页
AIM: To determine how glucocorticoids (GCs) may affect the growth and chemosensitivity of common carcinoma cells. METHODS: The effect of dexamethasone (DEX) on growth and chemosensitivity was assessed in 14 carc... AIM: To determine how glucocorticoids (GCs) may affect the growth and chemosensitivity of common carcinoma cells. METHODS: The effect of dexamethasone (DEX) on growth and chemosensitivity was assessed in 14 carcinoma cell lines. The function of GC receptors (GR) was assessed by MMTV reporter assay. Overexpression of GR was done by in vitro transfection and expression of a GR-expressing vector. Immunohistochemical stain of tissues and ceils were done by PA1-511A, an anti-GR monodonal antibody. RESULTS: DEX inhibited cell growth of four (MCF-7, MCF- 7/MXR1, MCF-7/TPT300, and HeLa), increased cisplatin cytoxicity of one (SiHa), and decreased dsplatin cytotoxicity of two (H460 and Hep3B) cell lines. The GR content of the seven cell lines affected by DEX was significantly higher than those of the seven cell lines unaffected by DEX (5.2±2.5×10^4 sites/cell vs1.3±1.4×10^4 sites/cell, P= 0.005). Only two DEX-unresponsive cell lines {NPC-TW01 and NPC- TW04) oontained high GR amounts in the range (1.9-8.1×10^4 sites/cell) of the seven DEX-responsive cell lines. The GR function of NPC-TW01 and NPC-TW04, however, was foundto be impaired. The importance of high cellular amount of GR in mediating DEX susceptibility of the cells was further exemplified by GR dose-dependent drug resistance to cisplatin of AGS, a cell line with low GR content and was unaffected by DEX before transfection of GR-expressing vector. Immunohistochemical studies of human cancer tissues showed that 5 of the 45 (11.1%) breast cancer and 43 of the 85 (50.6%) non-small cell lung cancer had high GR contents at the ranges of the GC-responsive carcinoma cell lines. CONCLUSION: The growth and chemosensitivity of human carcinomas with high GR contents may be affected by GC. However, in light of the heterogeneous and even contradictive effects of GC on these cells, routine examination of GR contents of human carcinoma tissues may not be clinically useful until other markers that help predict the ultimate effect of GC on individual patients are identified. 展开更多
关键词 GLUCOCORTICOIDS Glucocorticoid receptor CARCINOMA Cell growth Chemosensitivility Drug resistance
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Mathematical Analysis of Immune Response of HIV-I Including Delay 被引量:7
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作者 WANG Zhan-we WANG Wen-di 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第1期45-51,共7页
This paper considers a model of cell-to-cell spread of HIV-I with CTL immune response. By using a discrete delay to model the intracellular delay, it is shown that the uninfected equilibrium is globally asymptotical s... This paper considers a model of cell-to-cell spread of HIV-I with CTL immune response. By using a discrete delay to model the intracellular delay, it is shown that the uninfected equilibrium is globally asymptotical stable in some conditions and the sufficient condition to ensure the stability of the infected equilibrium does not change would be enlarged by Sturm sequence. Numerical simulations are presented to illustrate the results. 展开更多
关键词 HIV-I infection intercellular delay characteristic equation immune response
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Helicobacter pylori neutrophil activating protein as target for new drugs against H.pylori inflammation 被引量:5
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作者 Theodora Choli-Papadopoulou Filippos Kottakis +1 位作者 Georgios Papadopoulos Stefanos Pendas 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第21期2585-2591,共7页
Helicobacter pylori(H.pylori) infection is among the most common human infections and the major risk factor for peptic ulcer disease and gastric cancer.With-in this work we present the implication of C-terminal region... Helicobacter pylori(H.pylori) infection is among the most common human infections and the major risk factor for peptic ulcer disease and gastric cancer.With-in this work we present the implication of C-terminal region of H.pylori neutrophil activating protein in the stimulation of neutrophil activation as well as the evi-dence that the C-terminal region of H.pylori activating protein is indispensable for neutrophil adhesion to endothelial cells,a step necessary to H.pylori inflammation.In addition we show that arabino galactan proteins derived from chios mastic gum,the natural resin of the plant Pistacia lentiscus var.Chia inhibit neutrophil activation in vitro. 展开更多
关键词 Helicobacter pylori neutrophil activating protein Helicobacter pylori Peptic ulcer disease Gastric cancer
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