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打造有“生长感”的语文课堂 被引量:1
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作者 曹海 《教育研究与评论(小学教育教学)》 2015年第3期34-39,共6页
"教育即生长。"一切教育教学活动都应立足于儿童的生长,体现对儿童的关怀。语文教学应回归教学的原点,思考学科的基本规律,把握课程的基本特质,牢固树立课堂生长观;将学情分析作为开展一切教学活动的逻辑起点,探寻课堂生长点;关注课... "教育即生长。"一切教育教学活动都应立足于儿童的生长,体现对儿童的关怀。语文教学应回归教学的原点,思考学科的基本规律,把握课程的基本特质,牢固树立课堂生长观;将学情分析作为开展一切教学活动的逻辑起点,探寻课堂生长点;关注课堂上学生之间的补充、争辩、示范、组织等互动,提升课堂生长力。 展开更多
关键词 生长感 生长 生长 生长
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生态课堂的生长感探究 被引量:3
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作者 许丽萍 《上海教育科研》 北大核心 2015年第2期93-94,共2页
生态课堂是由静态本体论走向动态主体论的课堂,寻找生态课堂的生长感有助于落实以生为本的理念。在生态课堂中,我们应该更加关注学生本身的教育资源,特别是已有经验、错误表现、问题困惑、思维差异等,去探寻生长点;我们也应该更加关注... 生态课堂是由静态本体论走向动态主体论的课堂,寻找生态课堂的生长感有助于落实以生为本的理念。在生态课堂中,我们应该更加关注学生本身的教育资源,特别是已有经验、错误表现、问题困惑、思维差异等,去探寻生长点;我们也应该更加关注教师的引导策略,如课前挑战点的确立、课中突破点的解决、课后提升点的设置,去探寻生长力,最终促使师生互赢共长。 展开更多
关键词 生态课堂 生长感 探究
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机械感生长周期光纤光栅的可调谐环形光纤激光器 被引量:4
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作者 姜明顺 冯德军 隋青美 《光学精密工程》 EI CAS CSCD 北大核心 2010年第2期311-316,共6页
将采用机械感生法写制的长周期光纤光栅(MLPFG)串入环形腔中,设计了一种新颖的L波段可调谐环形掺铒光纤激光器(EDFL)。抽运光源为980nm半导体激光器,使用掺铒浓度为5×10-4,长度为12m的铒纤作为增益介质,通过调整待写制光纤与周期... 将采用机械感生法写制的长周期光纤光栅(MLPFG)串入环形腔中,设计了一种新颖的L波段可调谐环形掺铒光纤激光器(EDFL)。抽运光源为980nm半导体激光器,使用掺铒浓度为5×10-4,长度为12m的铒纤作为增益介质,通过调整待写制光纤与周期性压力槽之间的夹角,改变MLPFG的写制周期,调谐MLPFG透射谱,进而影响环形腔增益最高点,光纤激光器波长可调谐范围可达42nm(1562.465~1604.280nm),激光光谱3dB带宽<0.04nm,20dB带宽<0.08nm,边模抑制比>45dB。长时间观测表明,激光功率稳定性优于0.2dBm。实验显示,该光纤激光器具有带宽较宽,线宽较窄及性能稳定等特点。 展开更多
关键词 激光技术 掺铒光纤激光器(EDFL) 波长调谐 机械生长周期光纤光栅
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爱国主义教育要增强学生的体验感、获得感、生长感 被引量:1
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作者 江光华 《人民教育》 北大核心 2022年第21期46-46,共1页
读了2022年《人民教育》第18期《文化自信视角的爱国主义教育》一文,深受启发。结合日常小学德育工作实际,新时代爱国主义教育要切实增强学生的体验感、获得感、生长感。一是在共鸣中增强体验感。在小学阶段开展爱国主义教育,要充分利... 读了2022年《人民教育》第18期《文化自信视角的爱国主义教育》一文,深受启发。结合日常小学德育工作实际,新时代爱国主义教育要切实增强学生的体验感、获得感、生长感。一是在共鸣中增强体验感。在小学阶段开展爱国主义教育,要充分利用本土特色资源,使其.更加具有地域性和亲近感。要让爱国主义教育与学生日常学习、生活、交往等产生更多有意义的联系,用他们善于理解的方式呈现教育资源。 展开更多
关键词 爱国主义教育 《人民教育》 日常学习 教育资源 亲近 生长感 增强体验 小学德育工作
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具身实践赋予量感生长的力量
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作者 巫应新 《福建教育研究》 2022年第12期33-35,共3页
量感主要指对事物的可测量属性及大小关系的直观感知。量感的建立有助于培养学生的度量自觉,学会用“量”的眼光观察现实世界,学会用“量”的语言表达现实世界,逐步养成用定量的方法认识和解决问题的习惯。文章指出具身实践赋予量感生... 量感主要指对事物的可测量属性及大小关系的直观感知。量感的建立有助于培养学生的度量自觉,学会用“量”的眼光观察现实世界,学会用“量”的语言表达现实世界,逐步养成用定量的方法认识和解决问题的习惯。文章指出具身实践赋予量感生长的力量的三种路径:体验感知、刻画认知、思辨估测。 展开更多
关键词 具身实践 生长 体验 刻画认知 思辨估测
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高精度机械感生长周期光纤光栅横向压力传感系统 被引量:4
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作者 姜明顺 冯德军 隋青美 《光学学报》 EI CAS CSCD 北大核心 2010年第10期2855-2858,共4页
设计并实验研究了一种基于机械微应变引入长周期光纤光栅(MLPFG)的横向压力传感系统。利用机械线加工技术制作周期为600μm,长度为60 mm的不锈钢压力槽板,测定了槽板对待写制光纤施加的横向压力与MLPFG谐振峰峰值之间的关系,并借助布拉... 设计并实验研究了一种基于机械微应变引入长周期光纤光栅(MLPFG)的横向压力传感系统。利用机械线加工技术制作周期为600μm,长度为60 mm的不锈钢压力槽板,测定了槽板对待写制光纤施加的横向压力与MLPFG谐振峰峰值之间的关系,并借助布拉格光纤光栅(FBG)搭建了高精度横向压力解调系统。实验表明,在0~60 N的范围内,压力与MLPFG透射谱深度有很好的线性关系,线性度达0.9950,灵敏度约为0.35 dB/N。保持45 N的压力20 h,MLPFG谐振峰峰值最大波动小于0.06 dB,具备良好的稳定性。采用中心波长为1542.890 nm的FBG实现了系统解调,系统灵敏度为0.12μW/N,进一步提高了检测系统的实用性。 展开更多
关键词 光纤布拉格光栅 横向压力 机械生长周期光纤光栅 解调
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Evaluation on Killing Effects of Sensitive Plant Growth Inhibitors on Eupatorium adenophorum 被引量:1
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作者 戴红燕 华劲松 《Agricultural Science & Technology》 CAS 2014年第1期79-82,共4页
[Objective] Considering invasion of Eupatorium adenophorum, a growth in-hibitor of the plant was developed based on plant sensitivity, to make evaluation on control effects and to determine the optimal concentration. ... [Objective] Considering invasion of Eupatorium adenophorum, a growth in-hibitor of the plant was developed based on plant sensitivity, to make evaluation on control effects and to determine the optimal concentration. [Method] According to field test method, the effects of treatments with growth inhibitor at 0.5%, 1%, 1.5%and 2% on Eupatorium adenophorum were explored and the growth of other weeds was observed to research selectivity of plant inhibitor on the plant. [Result] The growth inhibitor had significant effects on ground parts of Eupatorium adenophorum. Specifical y, after 2 h, Eupatorium adenophorum was damaged seriously and the damage degree went worse upon inhibitor concentration. After 5 d, the control effect of the inhibitorreached 41.5% with concentration at 1.5%, reached 90.2% with the concentration at 1%, and 100% with the concentration at 1.5% and 2%. After 15 d, the control effect achieved 64.6%, 91.7%, 98.9% and 100% with concentrations at 0.5%, 1%, 1.5% and 2%. Stil , the effects of growth inhibitors on root system were limited. For example, new branches would grow from base part if the inhibitor con-centration is too low. On the other hand, the growth inhibitor is of sensitivity and selectivity, which would not hurt other plants. [Conclusion] It is feasible to rapidly control growth and development and even kil Eupatorium adenophorum based on plant sensitivity and it is proved that the growth inhibitor at 1.5% would considerably restrict and kil Eupatorium adenophorum. Therefore, the concentration of growth in-hibitors should be over 1.5%. 展开更多
关键词 Eupatorium adenophorum Sensitivity Growth inhibitor Control effects
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Evidence That the Auxin Signaling Pathway Interacts with Plant Stress Response 被引量:7
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作者 包方 李家洋 《Acta Botanica Sinica》 CSCD 2002年第5期532-536,共5页
Auxin influences a variety of developmental and physiological processes. Early reports, suggested that auxin might affect plant stress response. We have identified a number of auxin responsive genes in Arabidopsis tha... Auxin influences a variety of developmental and physiological processes. Early reports, suggested that auxin might affect plant stress response. We have identified a number of auxin responsive genes in Arabidopsis thaliana (L.) Heynh. by using cDNA an-ay and found that stress responsive genes, such as,Arabidopsis homolog of MEK kinase 1 (ATMEKK1), ReL/SpoT homolog 3 ( At-RSH3), Catalase 1 ( Cat1) and Ferritin 1 (Fer1), were down-regulated by auxin, indicating that auxin regulates ale expression of stress responsive genes. We also demonstrated that nitrilase genes, nitrilase I ( NIT]) and nitrilase 2 (NIT2) involving in indole-3-acetic acid (IAA) biosynthesis, were induced by salinity stress, suggesting that the level of IAA might increase in response to salinity stress. To dissect the signal pathway involved in the interaction, two auxin insensitive mutants, auxin resistant 2 (axr2) and auxin resistant 1-3 (axrl-3) were used. Stress responsive genes were induced by salt stress in wild type and axr2, but not in axr1-3. The result suggests that die interaction between auxin and stress responses may be linked in the ubiquitin pathway. 展开更多
关键词 AUXIN stress-responsive genes auxin insensitive mutants NITRILASE Arabidopsis thaliana
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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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The role of endotoxin,TNF-α,and IL-6 in inducing the state of growth hormone insensitivity 被引量:31
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作者 WangP LiN 《World Journal of Gastroenterology》 SCIE CAS CSCD 2002年第3期531-536,共6页
AIM: Critical illnesses such as sepsis, trauma, and burns cause a growth hormone insensitivity, which leads to an increased negative nitrogen balance. Endotoxin is generously released into blood under these conditions... AIM: Critical illnesses such as sepsis, trauma, and burns cause a growth hormone insensitivity, which leads to an increased negative nitrogen balance. Endotoxin is generously released into blood under these conditions and stimulates the production of proinflammatory cytokines such as TNF-alpha, IL-6, and IL-1, which may play a very important role in inducing the growth hormone insensitivity. The objective of this current study was to investigate the role of endotoxin, TNF-alpha and IL-6 in inducing the growth hormone insensitivity at the receptor and post-receptor levels. METHODS: Spague-Dawley rats were injected with endotoxin, TNF-alpha, and IL-6, respectively and part of rats injected with endotoxin was treated with exogenous somatotropin simultaneously. All rats were killed at different time points. The expression of IGF-I, GHR, SOCS-3 and beta-actin mRNA in the liver was detected by RT-PCR and the GH levels were measured by radioimmunoassay, the levels of TNF-alpha and IL-6 were detected by ELISA. RESULTS: There was no significant difference in serous GH levels between experimental group and control rats after endotoxin injection, however, liver IGF-I mRNA expression had been obviously down-regulated in endotoxemic rats. Liver GHR mRNA expression also had a predominant down-regulation after endotoxin injection. The lowest regulation of liver IGF-I mRNA expression occurred at 12h after LPS injection, being decreased by 53% compared with control rats. For GHR mRNA expression, the lowest expression occurred at 8h and had a 81% decrease. Although SOCS-3 mRNA was weakly expressed in control rats, it was strongly up-regulated after LPS injection and had a 7.84 times increase compared with control rats. Exogenous GH could enhance IGF-I mRNA expression in control rats, but it did fail to prevent the decline in IGF-I mRNA expression in endotoxemic rats. Endotoxin stimulated the production of TNF-alpha and IL-6, and the elevated IL-6 levels was shown a positive correlation with increased SOCS-3 mRNA expression. The liver GHR mRNA expression was obviously down-regulated after TNF-alpha iv injection and had a 40% decrease at 8h, but the liver SOCS-3 mRNA expression was the 4.94 times up-regulation occurred at 40 min after IL-6 injection. CONCLUSION: The growth hormone insensitivity could be induced by LPS injection, which was associated with down-regulated GHR mRNA expression at receptor level and with up-regulated SOCS-3 mRNA expression at post-receptor level. The in vivo biological activities of LPS were mediated by TNF-alpha and IL-6 indirectly, and TNF-alpha and IL-6 may exert their effects on the receptor and post-receptor levels respectively. 展开更多
关键词 Repressor Proteins Transcription Factors Animals Drug Resistance Growth Hormone Insulin-Like Growth Factor I INTERLEUKIN-6 LIPOPOLYSACCHARIDES Male Proteins RNA Messenger RATS Rats Sprague-Dawley Receptors Somatotropin Research Support Non-U.S. Gov't Suppressor of Cytokine Signaling Proteins Tumor Necrosis Factor-alpha
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New approaches in angiogenic targeting for colorectal cancer 被引量:6
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作者 Aleix Prat Esther Casado Javier Cortés 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第44期5857-5866,共10页
Colorectal carcinoma (CRC) is one of the leading causes of cancer death worldwide. In the last decade, the addition of irinotecan and oxaliplatin to standard fluorouracil-based chemotherapy regimens have set the new... Colorectal carcinoma (CRC) is one of the leading causes of cancer death worldwide. In the last decade, the addition of irinotecan and oxaliplatin to standard fluorouracil-based chemotherapy regimens have set the new benchmark of survival for patients with metastatic CRC at approximately 20 too. Despite these advances in the management of CRC, there is a strong medical need for more effective and well-tolerated therapies. The dependence of tumor growth and metastasis on blood vessels makes angiogenesis a rational target for therapy. One of the major pathways involved in this process is the vascular endothelial growth factor (VEGF) and its receptors (VEGFR). In 2004, the first agent targeting angiogenesis, bevacizumab (BV), was approved as an adjunct to first-line cytotoxic treatment of metastatic CRC. The role of BV as part of adjuvant treatment and in combination with other targeted therapies is the subject of ongoing trials. However, BV is associated with an increase in the risk of arterial thromboembolic events, hypertension and gastrointestinal perforations and its use must be cautious. Novel VEGFR TK inhibitors with different ranges of nanomolar potencies, selectivities, and pharmacokinetic properties are entering phase 111 trials for the treatment of cancer. Conversely, one of these novel agents, vatalanib, has been shown not to confer survival benefit in first and second-line treatment of advanced CRC. The basis of these findings is being extensively evaluated. Ongoing and new well-designed trials will define the optimal clinical application of the actual antiangiogenic agents, and, on the other hand, intensive efforts in basic research will identify new agents with different antiangiogenic approaches for the treatment of CRC. In this review we discuss and highlight current and future approaches in angiogenic targeting for CRC. 展开更多
关键词 Angiogenesis inhibitors Vascular endothelial growth factor VEGF receptors BEVACIZUMAB VATALANIB Colorectal carcinoma
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Transactivation of the TIEG1 confers growth inhibition of transforming growth factor-β-susceptible hepatocellular carcinoma cells 被引量:13
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作者 Lei Jiang Yiu-Kay Lai +6 位作者 Jin-Fang Zhang Chu-Yan Chan Gang Lu Marie CM Lin Ming-Liang He Ji-Cheng Li Hsiang-Fu Kung 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第17期2035-2042,共8页
AIM:To investigate the role of transforming growth factor(TGF)-β-inducible early gene 1(TIEG1) in TGF-β-induced growth inhibition in hepatocellular carcinoma(HCC) cells.METHODS:Human hepatocyte and HCC cell lines wi... AIM:To investigate the role of transforming growth factor(TGF)-β-inducible early gene 1(TIEG1) in TGF-β-induced growth inhibition in hepatocellular carcinoma(HCC) cells.METHODS:Human hepatocyte and HCC cell lines with varied susceptibilities to TGF-β1 were tested by methylthiazoletetrazolium(MTT) assay.The expression changes of Smad2,Smad3,Smad4,Smad7,TIEG1 and TIEG2 gene following treatment with TGF-β1 in a TGF-β-sensitive hepatocyte cell line(MIHA),a TGF-β-sensitive hepatoma cell line(Hep3B) and two TGF-β-insensitive hepatoma cell lines(HepG2 and Bel7404) were examined.SiRNA targeting TIEG1 was transfected into Hep3B cells and the sensitivity of cells to TGF-β1 was examined.Overexpression of TIEG1 was induced by lentiviral-mediated transduction in TGF-β1-resistant hepatoma cell lines(Bel7404 and HepG2).MTT assay and 4',6-Diamidino-2-phenylindole staining were used to identify cell viability and apoptosis,respectively.The expression level of stathmin was measured by reverse transcriptase polymerase chain reaction and Western-blotting analysis,and stathmin promoter activity by TIEG1 was monitored by a luciferase reporter gene system.RESULTS:TIEG1 was significantly upregulated by TGF-β1 in the TGF-β1-sensitive HCC cell line,Hep3B,but not in the resistant cell lines.The suppression of TIEG1 by siRNAs decreased the sensitivity of Hep3B cells to TGF-β1,whereas the overexpression of TIEG1 mediated growth inhibition and apoptosis in TGF-β1-resistant HCC cell lines,which resembled those of TGF-β1-sensitive HCC cells treated with TGF-β1.Our data further suggested that stathmin was a direct target of TIEG1,as stathmin was signif icantly downregulated by TIEG1 overexpression,and stathmin promoter activity was inhibited by TIEG1 in a dose-dependent manner.CONCLUSION:Our data suggest that transactivation of TIEG1 conferred growth inhibition of TGF-β-susceptible human HCC cells. 展开更多
关键词 Growth inhibition Hepatocellular carcinoma Stathmin Transforming growth factor-β Transforming growth factor-β-inducible early gene 1
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Yield Estimation Model of Citrus Based on Spectral Data and Agronomic Parameters 被引量:1
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作者 邹扬庆 罗红霞 +3 位作者 Habtom Yemane Tekle 王俊 余天霞 张锐 《Agricultural Science & Technology》 CAS 2013年第10期1513-1516,共4页
With the development of precision agriculture, the research that applies Remote Sensing technology, especially hyperspectral remote sensing, to realize crop management, monitoring and yield estimation, has been concer... With the development of precision agriculture, the research that applies Remote Sensing technology, especially hyperspectral remote sensing, to realize crop management, monitoring and yield estimation, has been concerned. Nowadays, the growth-monitoring and yield-estimating methods in rice, wheat and other annual crops develop rapidly with some achievements having already been put into service. But the yield estimation research on perennial economic crops is few. Taking peren- nial citrus trees as the research object, using ASD spectrometer to collect citrus canopy spectral, this article studied and analyzed the citrus of veget&tion index and its relationship on yield, synthetically considered the influence of the agriculture pa- rameters on crop yield, and finally constructed the citrus yield estimation model based on the spectral data and agronomic parameters. Through the Significance Test and Samples' Test, olutained that the model's fitting degree was R=0.631, F= 13.201, P〈0.01 and the error rate of estimating accuracy was controlled in the range 3%-16%, proving that the model has statistical signification and reliability. It concluded that hyperspectral acquired from citrus canopy has substantial potential for citrus yield estimation. This study is an application and exploration of Hyperspectral Remote Sensing technology in the citrus yield estimation. 展开更多
关键词 CITRUS Yield estimation Hyperspectral data Agronomic parameter
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A retrograde apoptotic signal originating in NGF-deprived distal axons of rat sympathetic neurons in compartmented cultures 被引量:3
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作者 Sue-Ann Mok Karen Lund Robert B Campenot 《Cell Research》 SCIE CAS CSCD 2009年第5期546-560,共15页
Previous investigations of retrograde survival signaling by nerve growth factor (NGF) and other neurotrophins have supported diverse mechanisms, but all proposed mechanisms have in common the generation of survival ... Previous investigations of retrograde survival signaling by nerve growth factor (NGF) and other neurotrophins have supported diverse mechanisms, but all proposed mechanisms have in common the generation of survival signals retrogradely transmitted to the neuronal cell bodies. We report the finding of a retrograde apoptotic signal in axons that is suppressed by local NGF signaling. NGF withdrawal from distal axons alone was sufficient to activate the pro-apoptotic transcription factor, c-jun, in the cell bodies. Providing NGF directly to cell bodies, thereby restoring a source of NGF-induced survival signals, could not prevent c-jun activation caused by NGF withdrawal from the distal axons. This is evidence that c-jun is not activated due to loss of survival signals at the cell bodies. Moreover, blocking axonal transport with colchicine inhibited c-jun activation caused by NGF deprivation suggesting that a retrogradely transported pro-apoptotic signal, rather than loss of a retrogradely transported survival signal, caused c-jun activation. Additional experiments showed that activation of c-jun, pro-caspase-3 cleavage, and apoptosis were blocked by the protein kinase C inhibitors, rottlerin and chelerythrine, only when applied to distal axons suggesting that they block the axon-specific pro-apoptotic signal. The rottlerin-sensitive mechanism was found to regulate glyco- gen synthase kinase 3 (GSK3) activity. The effect of siRNA knockdown, and pharmacological inhibition of GSK3 suggests that GSK3 is required for apoptosis caused by NGF deprivation and may function as a retrograde carrier of the axon apoptotic signal. The existence of a retrograde death signaling system in axons that is suppressed by neurotro- phins has broad implications for neurodevelopment and for discovering treatments for neurodegenerative diseases and neurotrauma. 展开更多
关键词 nerve growth factor apoptosis retrograde apoptotic signal sympathetic neuron axon glycogen synthase kinase 3 c-jun
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EPIDERMAL GROWTH FACTOR PREVENTS INCREASED PERMEABILITY AND BACTERIAL TRANSLOCATION IN RATS WITH ACUTE PANCREATITIS 被引量:3
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作者 陈冬利 王为忠 王俊义 《Chinese Medical Sciences Journal》 CAS CSCD 2001年第1期46-48,共3页
To evaluate the effects of epidermal growth factor (EGF) on intestinal permeability and bacterial translocation in rats with acute pancreatitis during total parenteral nutrition (TPN). Methods. Thirty- two male Spragu... To evaluate the effects of epidermal growth factor (EGF) on intestinal permeability and bacterial translocation in rats with acute pancreatitis during total parenteral nutrition (TPN). Methods. Thirty- two male Sprague- Dawley rats that underwent injection of 3.5% sodium taurocholate solution into the pancreatic duct were randomly divided into one of the following two groups: (1) received only TPN (control group) or (2) received TPN with EGF at a dose of 0.2 mg· kg- 1· day- 1 (Egf group). On fifth day of total parenteral nutrition, samples from mesenteric lymph nodes, pancreas, liver and spleen were harvested for cultures. Water, protein and DNA content in jejunal mucosa were determined. D- xylose and fluorescein isothiocyanate (FITC)- dextran were instilled into the lumen of a ligated segament of small intestine. Thirty minutes later, superior mesenteric vein D- xylose and plasma FITC- dextran concentration were measured. Results. Positive cultures in liver and spleen, as well as FITC- dextran concentration in the Egf group were significantly lower than in the control group. Protein and DNA content in jejunal mucosa in the Egf group were significantly higher than in the control group. Conclusion. The results indicate that EGF may prevent increased intestinal permeability and bacterial translocation in rats with acute pancreatitis during TPN. 展开更多
关键词 epidermal growth factor acute pancreatitis bacterial translocation
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Remote Sensing Data and SLEUTH Urban Growth Model:As Decision Support Tools for Urban Planning 被引量:2
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作者 SERASINGHE PATHIRANAGE Inoka Sandamali Lakshmi N.KANTAKUMAR SUNDARAMOORTHY Sivanantharajah 《Chinese Geographical Science》 SCIE CSCD 2018年第2期274-286,共13页
Sri Lanka is experiencing speedy urbanization by converting the agriculture land and other natural land cover into built-up land. The urban population of Sri Lanka is expected to reach to 60% by 2030 from 14% in 2010.... Sri Lanka is experiencing speedy urbanization by converting the agriculture land and other natural land cover into built-up land. The urban population of Sri Lanka is expected to reach to 60% by 2030 from 14% in 2010. The rapid growth in urban population and urban areas in Sri Lanka may cause serious socioeconomic disparities, if they are not handled properly. Thus, planners in Sri Lanka are in need of information about past and future urban growth patterns to plan a better and sustainable urban future for Sri Lanka. In this paper, we analyzed the characteristics of past land use and land cover trends in Matara City of Sri Lanka from 1980 to 2010 to assess the historic urban dynamics. The land use change detection analysis based on remote sensing datasets reveal that the conversion of homestead/garden and paddy into urban land is evident in Matara City. The historic urban trends are projected into the near future by using SLEUTH urban growth model to identify the hot spots of future urbanization and as well as the urban growth patterns in Matara City up to the basic administrative level, i.e., Grama Niladari Divisions(GND). The urban growth simulations for the year 2030 reveal that 29 GNDs out of 66 GNDs in Matara City will be totally converted into urban land. Whereas, 28 GNDs will have urban land cover from 75% to 99% by 2030. The urban growth simulations are further analyzed with respect to the proposed Matara city development plan by the Urban Development Authority(UDA) of Sri Lanka. The results show that the UDA's city development plan of Matara will soon be outpaced by rapid urbanization. Based on the calibration and validation results, the SLEUTH model proved to be a useful planning tool to understand the near future urbanization of Sri Lankan cities. 展开更多
关键词 urban growth urban planning land use land cover SLEUTH model Cellular Automata (CA) remote sensing Sri Lanka
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Spectrum Sensing Model for Wireless Internet of Things 被引量:1
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作者 温志刚 刘杰 《China Communications》 SCIE CSCD 2011年第1期8-13,共6页
In the last few years, the number of devices operating in wireless Internet of Things (IoT) has experienced tremendous growth. On the other hand, the growth results in spectrum scarcity. Cog- nitive Radio (CR) sys... In the last few years, the number of devices operating in wireless Internet of Things (IoT) has experienced tremendous growth. On the other hand, the growth results in spectrum scarcity. Cog- nitive Radio (CR) systems have been proposed to efficiently exploit the spectra that have been assigned but are underutilized. In this paper, a spectrum sensing model based on Markov chain is proposed to predict the spectrum hole for CR in wireless IoT. Theoretical analysis and simulation results have been evaluated that a Markov model with two- state or four-state works well enough in wireless loT whereas a model with more states is not necessary for it is complex. 展开更多
关键词 Internet of Things Cognitive Radio spectrum hole Markov chain
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Impacts of Climate Change on Net Primary Productivity in Arid and Semiarid Regions of China 被引量:15
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作者 WANG Hao LIU Guohua +3 位作者 LI Zongshan YE Xin WANG Meng GONG Li 《Chinese Geographical Science》 SCIE CSCD 2016年第1期35-47,共13页
In recent years, with the constant change in the global climate, the effect of climate factors on net primary productivity(NPP) has become a hot research topic. However, two opposing views have been presented in this ... In recent years, with the constant change in the global climate, the effect of climate factors on net primary productivity(NPP) has become a hot research topic. However, two opposing views have been presented in this research area: global NPP increases with global warming, and global NPP decreases with global warming. The main reasons for these two opposite results are the tremendous differences among seasonal and annual climate variables, and the growth of plants in accordance with these climate variables. Therefore, it will fail to fully clarify the relation between vegetation growth and climate changes by research that relies solely on annual data. With seasonal climate variables, we may clarify the relation between vegetation growth and climate changes more accurately. Our research examined the arid and semiarid areas in China(ASAC), which account for one quarter of the total area of China. The ecological environment of these areas is fragile and easily affected by human activities. We analyzed the influence of climate changes, especially the changes in seasonal climate variables, on NPP, with Climatic Research Unit(CRU) climatic data and Moderate Resolution Imaging Spectroradiometer(MODIS) satellite remote data, for the years 2000–2010. The results indicate that: for annual climatic data, the percentage of the ASAC in which NPP is positively correlated with temperature is 66.11%, and 91.47% of the ASAC demonstrates a positive correlation between NPP and precipitation. Precipitation is more positively correlated with NPP than temperature in the ASAC. For seasonal climatic data, the correlation between NPP and spring temperature shows significant regional differences. Positive correlation areas are concentrated in the eastern portion of the ASAC, while the western section of the ASAC generally shows a negative correlation. However, in summer, most areas in the ASAC show a negative correlation between NPP and temperature. In autumn, precipitation is less important in the west, as opposed to the east, in which it is critically important. Temperatures in winter are a limiting factor for NPP throughout the region. The findings of this research not only underline the importance of seasonal climate variables for vegetation growth, but also suggest that the effects of seasonal climate variables on NPP should be explored further in related research in the future. 展开更多
关键词 climate change net primary productivity (NPP) annual/seasonal variability trend analysis arid/semiarid regions of China(ASAC)
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Hepatitis C virus and ethanol alter antigen presentation in liver cells 被引量:4
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作者 Natalia A Osna 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第10期1201-1208,共8页
Alcoholic patients have a high incidence of hepatitis C virus (HCV) infection. Alcohol consumption enhances the severity of the HCV disease course and worsens the outcome of chronic hepatitis C. The accumulation of ... Alcoholic patients have a high incidence of hepatitis C virus (HCV) infection. Alcohol consumption enhances the severity of the HCV disease course and worsens the outcome of chronic hepatitis C. The accumulation of virally infected cells in the liver is related to the HCV- induced inability of the immune system to recognize infected cells and to develop the immune responses. This review covers the effects of HCV proteins and ethanol on major histocompatibility complex (MHC) class Ⅰ- and class Ⅱ-restricted antigen presentation. Here, we discuss the liver which functions as an immune privilege organ; factors, which affect cleavage and loading of antigenic peptides onto MHC class I and class ~I in hepatocytes and dendritic cells, and the modulating effects of ethanol and HCV on antigen presentation by liver cells. Altered antigen presentation in the liver limits the ability 'of the immune system to clear HCV and infected cells and contributes to disease progression. HCV by itself affects dendritic cell function, switching their cytokine profile to the suppressive phenotype of interleukin-10 (IL-10) and transforming growth factor beta (TGFβ) predominance, preventing cell maturation and allostimulation capacity. The synergistic action of ethanol with HCV results in the suppression of MHC class Ⅱ-restricted antigen presentation. In addition, ethanol metabolism and HCV proteins reduce proteasome function and interferon signaling, thereby suppressing the generation of peptides for MHC class I -restricted antigen presentation. Collectively, ethanol exposure further impairs antigen presentation in HCV-infected liver cells, which may provide a partial explanation for exacerbations and the poor outcome of HCV infection in alcoholics. 展开更多
关键词 ALCOHOL Antigen presentation HepatitisC Virus Interferon alpha and gamma Liver Majorhistocompatibility complex (MHC) class MHC class
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Crystal Growth of Nitrogenase CrFe Protein and MnFe Protein in Space 被引量:1
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作者 赵颖 赵剑峰 +4 位作者 吕玉兵 黄巨富 王耀萍 仓怀兴 毕汝昌 《Acta Botanica Sinica》 CSCD 2003年第9期1043-1048,共6页
Nitrogenase CrFe protein and MnFe protein were purified from a mutant strain UW3 of Azotobacter vinelandii Lipmann grown on a medium containing Cr and Mn, respectively. In order to meet the requirement for crystal gro... Nitrogenase CrFe protein and MnFe protein were purified from a mutant strain UW3 of Azotobacter vinelandii Lipmann grown on a medium containing Cr and Mn, respectively. In order to meet the requirement for crystal growth Of O-2-susceptible proteins including nitrogenase in space, crystallization conditions were optimized for the proteins using a simple and suitable device, as a replacement for the cumbersome anaerobic box (dry box), for anaerobic addition of the protein samples. In all used precipitant and protein solutions added in the simplified plexi glass box, CrFe protein and MnFe protein could be crystallized on the spacecraft in one week by the liquid/liquid diffusion method and vapor diffusion by the sitting drop method, respectively. All formed crystals were single on the spacecraft, but under the same condition twin crystals appeared on the ground. The size of the largest crystal grown in space from CrFe protein was 2-fold larger than that on the ground. But the size of the largest crystal grown in space from MnFe protein was not larger than that on the ground. The difference in crystal growth in space between CrFe protein and MnFe protein could be resulted from the crystallization method, rather than the kind of protein. 展开更多
关键词 mutant UW3 of Azotobacter vinelandii O-2-susceptible proteins nitrogenase CrFe protein and MnFe protein crystal growth in space
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