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The prognostic molecular markers in hepatocellular carcinoma 被引量:163
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作者 Lun-Xiu Qin Zhao-You Tang,Liver Cancer Institute and Zhongshan Hospital,Fudan University,Shanghai,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2002年第3期385-392,共8页
The prognosis of hepatocellular carcinoma (HCC) still remains dismal, although many advances in its clinical study have been made. It is important for tumor control to identify the factors that predispose patients to ... The prognosis of hepatocellular carcinoma (HCC) still remains dismal, although many advances in its clinical study have been made. It is important for tumor control to identify the factors that predispose patients to death. With new discoveries in cancer biology, the pathological and biological prognostic factors of HCC have been studied quite extensively. Analyzing molecular markers (biomarkers) with prognostic significance is a complementary method. A large number of molecular factors have been shown to associate with the invasiveness of HCC, and have potential prognostic significance. One important aspect is the analysis of molecular markers for the cellular malignancy phenotype. These include alterations in DNA ploidy, cellular proliferation markers (PCNA, Ki-67, Mcm2, MIB1, MIA, and CSE1L/CAS protein), nuclear morphology, the p53 gene and its related molecule MD M2, other cell cycle regulators (cyclin A, cyclin D, cyclin E, cdc2, p27, p73), oncogenes and their receptors (such as ras, c-myc, c-fms, HGF, c-met, and erb-B receptor family members), apoptosis related factors (Fas and FasL), as well as telomerase activity. Another important aspect is the analysis of molecular markers involved in the process of cancer invasion and metastasis. Adhesion molecules (E-cadherin, catenins, serum intercellular adhesion molecule-1, CD44 variants), proteinases involved in the degradation of extracellular matrix (MMP-2, MMP-9, uPA, uPAR, PAI), as well as other molecules have been regarded as biomarkers for the malignant phenotype of HCC, and are related to prognosis and therapeutic outcomes. Tumor angiogenesis is critical to both the growth and metastasis of cancers including HCC, and has drawn much attention in recent years. Many angiogenesis-related markers, such as vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), platelet-derived endothelial cell growth factor (PD-ECGF), thrombospondin (TSP), angiogenin, pleiotrophin, and endostatin (ES) levels, as well as intratumor microvessel density (M 展开更多
关键词 Apoptosis CARCINOGENS Carcinoma Hepatocellular Cell Adhesion Cell Division Cell nucleus Extracellular Matrix Genes p53 Humans Liver Neoplasms Neovascularization Pathologic PLOIDIES Prognosis Proteome TELOMERASE Tumor Markers Biological
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英语学习者朗读口语中的调核位置 被引量:50
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作者 陈桦 《解放军外国语学院学报》 北大核心 2006年第6期32-38,共7页
调核是语调单位(调群)中最突显的音节,是信息焦点。调核位置不同,信息中心也随之发生变化。本研究以Crystal(1975)的“调核约束理论”为依据,以实验语音学为研究手段,以8名英国大学生的调核位置为参照标准,对中国45名学习者的英语朗读... 调核是语调单位(调群)中最突显的音节,是信息焦点。调核位置不同,信息中心也随之发生变化。本研究以Crystal(1975)的“调核约束理论”为依据,以实验语音学为研究手段,以8名英国大学生的调核位置为参照标准,对中国45名学习者的英语朗读口语进行了分析。结果发现,学习者无标记调核的比例低于本族语者;在有标记调核中,非对比重音或新信息重音的语法项较多,尤其是人称代词的比例偏高,容易使信息焦点发生偏移,从而影响信息的传递及话语的理解。本研究对英语学习者如何有效地利用语调传递信息、突出英语语调教学重点均具有指导作用。 展开更多
关键词 调核 信息焦点 语调 学习者
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细胞色素c能诱导植物细胞编程性死亡 被引量:27
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作者 孙英丽 赵允 +1 位作者 刘春香 翟中和 《Acta Botanica Sinica》 CSCD 1999年第4期379-383,共5页
以悬浮培养的胡萝卜(DaucuscarotaL.)与烟草(NicotianatabacumL.cv.BY2)细胞原生质体为材料,加入一定浓度的细胞色素c和dATP。不同取样时间的DAPI荧光染色与电镜超薄切片观察的... 以悬浮培养的胡萝卜(DaucuscarotaL.)与烟草(NicotianatabacumL.cv.BY2)细胞原生质体为材料,加入一定浓度的细胞色素c和dATP。不同取样时间的DAPI荧光染色与电镜超薄切片观察的结果显示染色质发生凝集、趋边化,最终形成凋亡小体。核酸电泳显示DNA发生特异降解并形成电泳“阶梯”(DNAladder)。用末端脱氧核糖核酸转移酶介导的dUTP切口末端标记方法(TUNEL)检测发现DNA的3'OH断端被原位特异标记。以上结果说明:细胞色素c能诱导植物细胞发生典型的凋亡。 展开更多
关键词 细胞色素C 编程性细胞死亡 细胞核 植物细胞
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Cd^(2+)或Hg^(2+)水污染对菱体细胞的细胞核及叶绿体超微结构的影响 被引量:23
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作者 李大辉 施国新 《植物资源与环境》 CAS CSCD 1999年第2期43-48,共6页
用Cd2+、Hg2+两种重金属离子溶液培育菱(TrapabicornisOsbeck.)植物体后,观察体细胞的细胞核及叶绿体超微结构的变化。处理后第8天,菱浮水叶叶片和不定根细胞中细胞核的染色质与核质遭到破坏,不定根... 用Cd2+、Hg2+两种重金属离子溶液培育菱(TrapabicornisOsbeck.)植物体后,观察体细胞的细胞核及叶绿体超微结构的变化。处理后第8天,菱浮水叶叶片和不定根细胞中细胞核的染色质与核质遭到破坏,不定根中细胞核的核仁消失。但在各处理浓度(10μmol/L~50μmol/LCd2+或Hg2+)下,核膜均保持完整。叶片细胞的叶绿体基粒数目减少,基粒片层解体,叶绿体双层膜断裂,叶绿体中的质体球流入细胞基质中。两种结构的破坏程度随处理的离子浓度提高而增大。说明菱体细胞超微结构的变化观测可作为监测重金属污染的一种方法。 展开更多
关键词 重金属离子 水污染 细胞核 叶绿体
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磁性椰壳活性炭的合成研究 被引量:25
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作者 刘守新 孙承林 《新型炭材料》 SCIE EI CAS CSCD 2002年第1期45-48,共4页
根据表面活性剂特殊的分子结构 ,以顺磁性材料为磁核 ,在其表面先后覆盖内层、外层两层表面活性剂的单分子膜 ,合成磁化剂。依靠磁化剂外层单分子膜亲水基团的作用使磁化剂与椰壳活性炭键合在一起 ,活性炭因此被赋予磁性。通过对磁化剂... 根据表面活性剂特殊的分子结构 ,以顺磁性材料为磁核 ,在其表面先后覆盖内层、外层两层表面活性剂的单分子膜 ,合成磁化剂。依靠磁化剂外层单分子膜亲水基团的作用使磁化剂与椰壳活性炭键合在一起 ,活性炭因此被赋予磁性。通过对磁化剂用量、pH值、活化剂等因素对椰壳磁性活性炭磁化率影响的研究。确定了椰壳磁性活性炭的最佳合成条件为 :MR 2 0为磁化剂、pH值为 1.8~ 2 .4、在 6 0℃时加入适当无机盐类活化剂。 展开更多
关键词 椰壳活性炭 磁核 表面活性剂 磁化剂 磁性椰壳活性炭
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Neural mechanism of gastric motility regulation by electroacupuncture at RN12 and BL21: A paraventricular hypothalamic nucleus-dorsal vagal complex-vagus nervegastric channel pathway 被引量:27
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作者 Hao Wang Wen-Jian Liu +3 位作者 Guo-Ming Shen Meng-Ting Zhang Shun Huang Ying He 《World Journal of Gastroenterology》 SCIE CAS 2015年第48期13480-13489,共10页
AIM: To study the neural mechanism by which electroacupuncture(EA) at RN12(Zhongwan) and BL21(Weishu) regulates gastric motility.METHODS: One hundred and forty-four adult Sprague Dawley rats were studied in four separ... AIM: To study the neural mechanism by which electroacupuncture(EA) at RN12(Zhongwan) and BL21(Weishu) regulates gastric motility.METHODS: One hundred and forty-four adult Sprague Dawley rats were studied in four separate experiments. Intragastric pressure was measured using custommade rubber balloons, and extracellular neuron firing activity, which is sensitive to gastric distention in the dorsal vagal complex(DVC), was recorded by an electrophysiological technique. The expression levels of c-fos, motilin(MTL) and gastrin(GAS) in the paraventricular hypothalamic nucleus(PVN) were assayed by immunohistochemistry, and the expression levels of motilin receptor(MTL-R) and gastrin receptor(GAS-R) in both the PVN and the gastric antrum were assayed by western blotting.RESULTS: EA at RN12 + BL21(gastric Shu and Mu points), BL21(gastric Back-Shu point), RN12(gastric Front-Mu point), resulted in increased neuron-activating frequency in the DVC(2.08 ± 0.050, 1.17 ± 0.023, 1.55 ± 0.079 vs 0.75 ± 0.046, P < 0.001) compared with a model group. The expression of c-fos(36.24 ± 1.67, 29.41 ± 2.55, 31.79 ± 3.00 vs 5.73 ± 2.18, P < 0.001), MTL(22.48 ± 2.66, 20.76 ± 2.41, 19.17 ± 1.71 vs 11.68 ± 2.52, P < 0.001), GAS(24.99 ± 2.95, 21.69 ± 3.24, 23.03 ± 3.09 vs 12.53 ± 2.15, P < 0.001), MTL-R(1.39 ± 0.05, 1.22 ± 0.05, 1.17 ± 0.12 vs 0.84 ± 0.06, P < 0.001), and GAS-R(1.07 ± 0.07, 0.91 ± 0.06, 0.78 ± 0.05 vs 0.45 ± 0.04, P < 0.001) increased in the PVN after EA compared with the model group. The expression of MTL-R(1.46 ± 0.14, 1.26 ± 0.11, 0.99 ± 0.07 vs 0.65 ± 0.03, P < 0.001), and GAS-R(1.63 ± 0.11, 1.26 ± 0.16, 1.13 ± 0.02 vs 0.80 ± 0.11, P < 0.001) increased in the gastric antrum after EA compared with the model group. Damaging the PVN resulted in reduced intragastric pressure(13.67 ± 3.72 vs 4.27 ± 1.48, P < 0.001). These data demonstrate that the signals induced by EA stimulation of acupoints RN12 and BL21 are detectable in the DVC and the PVN, and increase the levels of gastrointestinal hormo 展开更多
关键词 DORSAL VAGAL complex GASTRIN RECEPTOR MOTILIN RECEPTOR Neuronal firing activity Paraventricularhypothalamic nucleus RN12 BL21
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细胞核内肌动蛋白参与基因转录的研究进展 被引量:24
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作者 王洪振 程焉平 《吉林师范大学学报(自然科学版)》 2005年第2期34-36,共3页
肌动蛋白是一种重要的细胞质蛋白质,但近来研究发现细胞核内也存在肌动蛋白.本文简要综述了肌动蛋白在细胞核内的存在和肌动蛋白参与基因转录的研究进展.
关键词 肌动蛋白 细胞核
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Transplantation of cholinergic neural stem cells in a mouse model of (Alzheimer’s) disease 被引量:20
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作者 WANGQing-hua XURu-xiang SeigoNagao 《Chinese Medical Journal》 SCIE CAS CSCD 2005年第6期508-511,共4页
It is believed that the degeneration of cholinergic cells in the nucleus basalis of Meynert (NBM) and the loss of cortical cholinergic innervation (cause dementia) of Alzheimer’s disease (AD).~1 (Currently available)... It is believed that the degeneration of cholinergic cells in the nucleus basalis of Meynert (NBM) and the loss of cortical cholinergic innervation (cause dementia) of Alzheimer’s disease (AD).~1 (Currently available) therapeutic interventions are mainly aimed at alleviating the cholinergic deficits. Unfortunately, these strategies do not prevent the disease, but instead offer limited symptomatic improvement.~2 A recent study demonstrated that transplantation of in vitro expanded neural stem cells (NSCs) in an animal model of Parkinson’s disease (PD) resulted in functional recovery of the animals to some extent,~2 suggesting that such neural precursors might offer a useful future therapy for AD. In this study, we tried to find whether mouse embryonic stem (ES) cell derived cholinergic NSCs grafted in the prefrontal and parietal cortex have effects on the disruption of spatial memory following development of lesion in NBM. 展开更多
关键词 Alzheimer disease neural stem cell· basal nucleus of meynert ACETYLCHOLINE
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Transplantation of gene-modified nucleus pulposus cells reverses rabbit intervertebral disc degeneration 被引量:22
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作者 LIU Yong LI Jian-min HU You-gu 《Chinese Medical Journal》 SCIE CAS CSCD 2011年第16期2431-2437,共7页
Background Intervertebral disc degeneration is the main cause of low back pain. The purpose of this study was to explore potential methods for reversing the degeneration of lumbar intervertebral discs by transplantati... Background Intervertebral disc degeneration is the main cause of low back pain. The purpose of this study was to explore potential methods for reversing the degeneration of lumbar intervertebral discs by transplantation of gene-modified nucleus pulposus cells into rabbit degenerative lumbar intervertebral discs after transfecting rabbit nucleus pulposus cells with adeno-associated virus 2 (AAV2)-mediated connective tissue growth factor (CTGF) and tissue inhibitor of metalloproteinases 1 (TIMP1) genes in vitro. Methods Computer tomography (CT)-guided percutaneous annulus fibrosus injury was performed to build degenerative lumbar intervertebral disc models in 60 New Zealand white rabbits, rAAV2-CTGF-IRES-TIMPI-transfected rabbit nucleus pulposus cells were transplanted into degenerative lumbar intervertebral discs (transplantation group), phosphate-buffered saline (PBS) was injected into degenerative lumbar intervertebral discs (degeneration control group) and normal lumbar intervertebral discs served as a blank control group. After 6, 10 and 14 weeks, the disc height index (DHI) and signal intensity in intervertebral discs were observed by X-ray and magnetic resonance imaging (MRI) analysis The expression of CTGF and TIMP1 in nucleus pulposus tissue was determined by Western blotting analysis, the synthesis efficiency of proteoglycan was determined by a 35S-sulfate incorporation assay, and the mRNA expression of type II collagen and proteoglycan was detected by RT-PCR. Results MRI confirmed that degenerative intervertebral discs appeared two weeks after percutaneous puncture. Transgenic nucleus pulposus cell transplantation could retard the rapid deterioration of the DHI. MRI indicated that degenerative intervertebral discs were relieved in the transplantation group compared with the degeneration control group. The expression of collagen II mRNA and proteoglycan mRNA was significantly higher in the transplantation group and the blank control group compared with the degeneration 展开更多
关键词 nucleus pulposus cells TRANSPLANTATION GENE-MODIFIED degenerative intervertebral disc
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牛磺酸对大鼠心肌损伤时心肌细胞核钙转运功能异常的保护作用 被引量:16
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作者 万福生 曾昭建 +1 位作者 赵小曼 罗达亚 《中国临床药理学与治疗学》 CAS CSCD 2000年第1期25-27,共3页
目的观察异丙肾上腺素 (ISO)致大鼠心肌缺血损伤时心肌细胞核钙转运功能的异常变化及牛磺酸对其影响。方法给Wister大鼠皮下注射5mg·kg-1ISO液 ,造成心肌缺血损伤模型。超速离心分离纯化心肌细胞核。酶学方法鉴定核纯度和测定核膜C... 目的观察异丙肾上腺素 (ISO)致大鼠心肌缺血损伤时心肌细胞核钙转运功能的异常变化及牛磺酸对其影响。方法给Wister大鼠皮下注射5mg·kg-1ISO液 ,造成心肌缺血损伤模型。超速离心分离纯化心肌细胞核。酶学方法鉴定核纯度和测定核膜Ca 2 +_ATP酶活性 ,同位素法观测核钙的摄取。结果与正常对照组比较 ,心肌缺血组 (实验组 )心肌细胞核膜钙依赖性ATPase活性降低18.1 % (P<0.05) ,45Ca2 +摄取效率也显著降低 ,其最大速度降低54.6 % ;牛磺酸保护组心肌细胞核Ca2 +_ATPase活性及核45Ca2 +摄取与正常对照组比较均未见显著性改变。 展开更多
关键词 心肌损伤 钙转运 细胞核 牛磺酸
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实时操作系统及其在列车运行控制系统中的应用分析 被引量:4
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作者 燕飞 唐涛 《北方交通大学学报》 CSCD 北大核心 2002年第6期69-74,共6页
介绍了嵌入式系统的现状和发展,具体阐述了实时操作系统(RTOS)的特点,描述了实时操作系统的最新发展以及它的应用前景,并探讨了Nucleus在列车运行控制系统中应用的可行性.
关键词 实时操作系统 嵌入式系统 列车运行控制系统 nucleus 安全计算机 嵌入式计算机
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关于茭白黑粉菌的正名问题 被引量:18
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作者 程岩 沈崇尧 裘维蕃 《真菌学报》 CSCD 北大核心 1989年第1期9-16,81-82,共8页
茭白黑粉菌在文献中出现Yenia esculenta(P.Henn.)Liou及Ustilago esculenta P.Henn.两个名字。现经形态发生学的研究以明确新名字是否有效。此菌冬孢子没有休眠期,孢子成熟后在适宜的环境中即可萌发。萌发的最适pH值为6;最适温度为25%... 茭白黑粉菌在文献中出现Yenia esculenta(P.Henn.)Liou及Ustilago esculenta P.Henn.两个名字。现经形态发生学的研究以明确新名字是否有效。此菌冬孢子没有休眠期,孢子成熟后在适宜的环境中即可萌发。萌发的最适pH值为6;最适温度为25%;不需要外界光的诱导,在黑暗条件下也能正常萌发;培养基中的营养成份对孢子萌发的速率有一定影响。冬孢子在不同的环境条件下,其萌发形态及方式都是稳定的:孢子萌发时产生有隔的担子或先菌丝(promycelium)。该先菌丝起初可以是无隔的,但生长到一定程度,便产生分隔,分隔多为2—4个。初生的先菌丝和小孢子是单核的,但成熟的先菌丝、小孢子及短菌丝细胞内均是双核的。可以认为,该菌的双核期在整个生活史中占有相当长的时间,它只有短暂的单核期。没有发现先菌丝、小孢子彼此之间或相互间融合的现象;未见到双核的融合及减数分裂过程。茭白黑粉菌在人工组合培养基上生成厚壁的孢子,较自然界中的冬孢子为大,但萌发方式则相同。最后作者等认为茭白黑粉菌仍应保留在Ustilago属中,而Yenia esculenta(P.Henn.)Liou的名字是无效的。 展开更多
关键词 茭白黑粉菌 菰黑粉菌 孢子萌发
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基于嵌入式Web服务技术的电力测控装置设计与实现 被引量:14
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作者 朱瑾 龚世敏 王青云 《电脑与电信》 2008年第9期27-29,35,共4页
本文对基于摩托罗拉MCU68332核心处理器及Nucleus Plus实时多任务操作系统的电力测控装置的硬件构架及软件平台设计进行介绍,重点对基于该平台的嵌入式Web服务技术应用研究,包括HTTP引擎、HTML页面模型预处理及应用程序接口的实现过程... 本文对基于摩托罗拉MCU68332核心处理器及Nucleus Plus实时多任务操作系统的电力测控装置的硬件构架及软件平台设计进行介绍,重点对基于该平台的嵌入式Web服务技术应用研究,包括HTTP引擎、HTML页面模型预处理及应用程序接口的实现过程及方法进行探讨。相比传统的测控装置,具有嵌入式Web服务功能的测控装置的优点在于可以实现远程管理维护,为设备的运行、调试带来很大的方便。 展开更多
关键词 嵌入式系统 WEB服务器 测控装置 MCU68332 nucleus PLUS
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Role of mitogen-activated protein kinases in the regulation of paraventricular nucleus to gastric ischemia-reperfusion injuries 被引量:17
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作者 LI Li ZHANG Yong-mei +2 位作者 QIAO Wei-li ZHANG Jian-fu WANG Lin 《Chinese Medical Journal》 SCIE CAS CSCD 2007年第12期1082-1087,共6页
Background We investigated the role in electrical stimulations of paraventricular nucleus (PVN) on gastric mucosal cells and the activity of mitogen-activated protein kinases (MAPKs) family members induced by gast... Background We investigated the role in electrical stimulations of paraventricular nucleus (PVN) on gastric mucosal cells and the activity of mitogen-activated protein kinases (MAPKs) family members induced by gastric ischemia-reperfusion (GI-R). And we elucidated the molecular mechanisms of the protection of PVN from GI-R injuries. Methods Sprague-Dawley rats were divided randomly into 4 groups: Group I, the sham-operated GI-R control group; Group II, the sham-operated electrical stimulations to PVN + sham-operated GI-R control group; Group III, the GI-R group; and Group IV, the electrical stimulations to PVN + GI-R group. In all of the experiments, the PVN was stimulated prior to the induction of GI-R. The GI-R model was established by clamping the celiac artery for 30 minutes to induce ischemia and then was released to allow reperfusion for 30 minutes, 1 hour, 3 hours and 6 hours, respectively. The gastric mucosal cellular apoptosis, proliferation, and the expression and activity of MAPKs protein were observed by immunohistochemistry and Western blotting, respectively. Results Compared with the GI-R group, the application of electrical stimulations in the PVN significantly depressed gastric mucosal cellular apoptosis and enhanced gastric mucosal cellular proliferation following the 30-minute, 1-hour and 3-hour intervals of reperfusion; it also promoted the activation of p-ERK during the early phase of reperfusion but inhibited the activation of p-JNK1/2 and p-p38 following the 30-minute, 1-hour and 3-hour intervals of reperfusion. Conclusions The protection of PVN against GI-R injuries may attribute to the inhibition of apoptosis and the promotion of the proliferation of gastric mucosal cells during GI-R. This protective effect is mediated by activating the ERK pathway and depressing the JNK, the JNK. p38 MAPK oathwavs of the oastric mucosal cells. 展开更多
关键词 paraventricular nucleus gastric ischemia-reperfusion PROLIFERATION apoptosis mitogen-activated protein kinases
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NUTRITIONAL LIPID LIVER DISEASE OF GRASS CARP CTENOPHARYNGODON IDULLUS(C.et V.) 被引量:17
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作者 林鼎 毛永庆 蔡发盛 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1990年第4期363-373,共11页
The inadequate nutrient content of pellet feeds widely used in recent years in China for grass carp forming led to lipid liver degeneration in the fish. The present studies show that the pathological features of lipid... The inadequate nutrient content of pellet feeds widely used in recent years in China for grass carp forming led to lipid liver degeneration in the fish. The present studies show that the pathological features of lipid liver disease are anaemia and hepatic ceroidosis. Other clinical features are: the ratio of liver to body weight exceeds 3% and lipid content exceeds 5%. Extreme infiltration of hepaiocytes by lipid results in the following deteriorative effects: swelling of the liver cells, increase of lipid droplets in the cytoplasm and dislocation of the nucleus, loss of cytoplasm staining affinity, and increased activities of GOT and GPT in serum. Lipid liver degeneration of grass carp can be divided into three stages: 1) deposition of liver lipid; 2) lipid infiltration of hepatic parenchyma; 3) atrophy of liver nucleus. The causes of lipid liver degeneration are complicated, but the main cause is assumed to be an imbalance of nutrients in daily feed and the lack of some lipotropic substances. 展开更多
关键词 DEGENERATION infiltration CYTOPLASM LIPID ATROPHY nucleus nutrients imbalance swelling affinity
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Intrinsically photosensitive retinal ganglion cells 被引量:18
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作者 Gary E.PICKARD Patricia J.SOLLARS 《Science China(Life Sciences)》 SCIE CAS 2010年第1期58-67,共10页
A new mammalian photoreceptor was recently discovered to reside in the ganglion cell layer of the inner retina.These intrinsically photosensitive retinal ganglion cells(ipRGCs) express a photopigment,melanopsin,that c... A new mammalian photoreceptor was recently discovered to reside in the ganglion cell layer of the inner retina.These intrinsically photosensitive retinal ganglion cells(ipRGCs) express a photopigment,melanopsin,that confers upon them the ability to respond to light in the absence of all rod and cone photoreceptor input.Although relatively few in number,ipRGCs extend their dendrites across large expanses of the retina making them ideally suited to function as irradiance detectors to assess changes in ambient light levels.Phototransduction in ipRGCs appears to be mediated by transient receptor potential channels more closely resembling the phototransduction cascade of invertebrate rather than vertebrate photoreceptors.ipRGCs convey irradiance information centrally via the optic nerve to influence several functions.ipRGCs are the primary retinal input to the hypothalamic suprachiasmatic nucleus(SCN),a circadian oscillator and biological clock,and this input entrains the SCN to the day/night cycle.ipRGCs contribute irradiance signals that regulate pupil size and they also provide signals that interface with the autonomic nervous system to regulate rhythmic gene activity in major organs of the body.ipRGCs also provide excitatory drive to dopaminergic amacrine cells in the retina,providing a novel basis for the restructuring of retinal circuits by light.Here we review the ground-breaking discoveries,current progress and directions for future investigation. 展开更多
关键词 MELANOPSIN CIRCADIAN RHYTHMS SUPRACHIASMATIC nucleus retina pupillary light REFLEX
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Quantale中的理想 被引量:13
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作者 王顺钦 赵彬 《陕西师范大学学报(自然科学版)》 CAS CSCD 北大核心 2003年第4期7-10,共4页
给出了Quantale中(左,右)理想的概念,讨论了Quantale中任意子集生成的(左,右)理想的具体结构,研究了Quantale中的理想与它的格意义下理想之间的关系.得到了当Q是可换Quantale时,Id(Q)中元是幂等的充要条件.
关键词 QUANTALE 理想 充要条件 核映射 格结构
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改良小切口非超声乳化术治疗高龄硬核白内障 被引量:18
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作者 郎雪华 陈明华 《中华眼外伤职业眼病杂志》 2013年第12期935-938,共4页
目的探讨改良式小切口非超声乳化白内障摘出人工晶状体植入术在高龄硬核白内障的中的临床应用。方法对82例高龄患者104眼硬核白内障施行改良式小切口非超声乳化白内障摘出人工晶状体植入术,并与同期81例高龄患者103眼硬核白内障施行晶... 目的探讨改良式小切口非超声乳化白内障摘出人工晶状体植入术在高龄硬核白内障的中的临床应用。方法对82例高龄患者104眼硬核白内障施行改良式小切口非超声乳化白内障摘出人工晶状体植入术,并与同期81例高龄患者103眼硬核白内障施行晶状体超声乳化吸出人工晶状体植入术对比,术后随访12个月,比较两种手术时间、角膜内皮细胞的密度、丢失率,以及术后视力。结果两种手术方式的手术时间差异无统计学意义(P〉0.05),在角膜内皮细胞密度、丢失率和术后视力的比较差异有统计学意义(P〈0.05)。结论高龄硬核白内障适宜行改良式小切口非超声乳化白内障摘出人工晶状体植入术,且有损伤小、恢复快等优点。 展开更多
关键词 白内障摘出 改良式 小切El 白内障 硬核 内皮细胞 角膜
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Induction of apoptosis by TPA and VP-16 is through translocation of TR3 被引量:14
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作者 LiuS WuQ 《World Journal of Gastroenterology》 SCIE CAS CSCD 2002年第3期446-450,共5页
AIM: To investigate the role of TR3 in induction of apoptosis in gastric cancer cells. METHODS: Human gastric cancer cell line, MGC80-3, was used. Expression of TR3 mRNA and its protein was detected by Northern blot a... AIM: To investigate the role of TR3 in induction of apoptosis in gastric cancer cells. METHODS: Human gastric cancer cell line, MGC80-3, was used. Expression of TR3 mRNA and its protein was detected by Northern blot and Western blot. Localization of TR3 protein was showed by immunofluorescence analysis under laser-scanning confocal microscope. Apoptotic morphology was observed by DAPI fluorescence staining, and apoptotic index was counted among 1000 cells randomly. Stable transfection assay was carried out by Lipofectamine. RESULTS: Treatment of MGC80-3 cells with TPA and VP-16 resulted in apoptosis, accompanied by the repression of Bcl-2 protein in a time-dependent manner. At the same time, TPA and VP-16 also up-regulated expression level of TR3 mRNA in MGC80-3 cells that expressed TR3 mRNA. When antisense-TR3 expression vector was transfected into the cells, expression of TR3 protein was repressed. In this case, TPA and VP-16 did not induce apoptosis. In addition, TPA and VP-16-induced apoptosis involved in translocation of TR3. In MGC80-3 cells, TR3 localized concentrative in nucleus, after treatment of cells with TPA and VP-16, TR3 translocated from nucleus to cytosol obviously. However, when this nuclear translocation was blocked by LMB, apoptosis was not occurred in MGC80-3 cells even in the presence of TPA and VP-16. CONCLUSION: Induction of apoptosis by TPA and VP-16 is through induction of TR3 expression and translocation of TR3 from nucleus to cytosol, which may be a novel signal pathway for TR3, and represent the new biological function of TR3 to exert its effect on apoptosis in gastric cancer cells. 展开更多
关键词 Active Transport Cell nucleus APOPTOSIS DNA-Binding Proteins ETOPOSIDE Gene Expression RNA Messenger RNA Neoplasm Receptors Cytoplasmic and Nuclear Receptors Steroid Research Support Non-U.S. Gov't Signal Transduction Stomach Neoplasms Tetradecanoylphorbol Acetate Transcription Factors Tumor Cells Cultured
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头孢菌素类品种研发与生产现状探讨 被引量:16
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作者 刘家健 《中国抗生素杂志》 CAS CSCD 北大核心 2006年第2期100-106,共7页
本文阐明了头孢菌素类抗生素其母核来源为7-ACA,7-ADCA,GCLE;并对其C2-,C3-,C7-结构修饰方法进行了综述。针对我国走仿创结合的产品研发思路提出了建议。
关键词 头孢菌素类抗生素 母核 结构修饰 研发思路
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