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Characterization of microRNAs in serum: a novel class of biomarkers for diagnosis of cancer and other diseases 被引量:982
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作者 Xi Chen Yi Ba +26 位作者 Lijia Ma Xing Cai Yuan Yin Kehui Wang Jig ang Guo Yujing Zhang Jiangning Chen Xing Guo Qibin Li Xiaoying Li Wenjing Wang Yan Zhang Jin Wang Xueyuan Jiang Yang Xiang Chen Xu Pingping Zheng Juanbin Zhang Ruiqiang Li Hongjie Zhang Xiaobin Shang Ting Gong Guang Ning Jun Wang Ke Zen Junfeng Zhang Chen-Yu Zhang 《Cell Research》 SCIE CAS CSCD 2008年第10期997-1006,共10页
Dysregulated expression of microRNAs (miRNAs) in various tissues has been associated with a variety of diseases, including cancers. Here we demonstrate that miRNAs are present in the serum and plasma of humans and o... Dysregulated expression of microRNAs (miRNAs) in various tissues has been associated with a variety of diseases, including cancers. Here we demonstrate that miRNAs are present in the serum and plasma of humans and other animals such as mice, rats, bovine fetuses, calves, and horses. The levels of miRNAs in serum are stable, reproducible, and consistent among individuals of the same species. Employing Solexa, we sequenced all serum miRNAs of healthy Chinese subjects and found over 100 and 91 serum miRNAs in male and female subjects, respectively. We also identified specific expression patterns of serum miRNAs for lung cancer, colorectal cancer, and diabetes, providing evidence that serum miRNAs contain fingerprints for various diseases. Two non-small cell lung cancer-specific serum miRNAs obtained by Solexa were further validated in an independent trial of 75 healthy donors and 152 cancer patients, using quantitative reverse transcription polymerase chain reaction assays. Through these analyses, we conclude that serum miRNAs can serve as potential biomarkers for the detection of various cancers and other diseases. 展开更多
关键词 serum-microRNA expression profile FINGERPRINT blood-based biomarker Solexa CANCERS diabetes
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转基因植物中外源基因的遗传学行为 被引量:61
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作者 华志华 黄大年 《Acta Botanica Sinica》 CSCD 1999年第1期1-5,共5页
The integration and expression of exogenes were reviewed in transgenic plants (T0 generation) as well as in their progenies. It was analyzed that the integration, expression and stable inheritance of exogenes were dif... The integration and expression of exogenes were reviewed in transgenic plants (T0 generation) as well as in their progenies. It was analyzed that the integration, expression and stable inheritance of exogenes were different in various transformation events. The disadvantages of present transformation methods and new transformation methods which can site specifically introduce exogenes into receipt chromosomes with restricted copies were discussed. 展开更多
关键词 转基因植物 外源基因 整合 表达 遗传
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A Major QTL, Ghd8, Plays Pleiotropic Roles in Regulating Grain Productivity, Plant Height, and Heading Date in Rice 被引量:138
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作者 Wen-Hao Yan Peng Wang Hua-Xia Chen Hong-Ju Zhou Qiu-Ping Li Chong-Rong Wang Ze-Hong Ding Yu-Shan Zhang Si-Bin Yu Yong-Zhong Xing Qi-Fa Zhang 《Molecular Plant》 SCIE CAS CSCD 2011年第2期319-330,共12页
Rice yield and heading date are two distinct traits controlled by quantitative trait loci (QTLs). The dissection of molecular mechanisms underlying rice yield traits is important for developing high-yielding rice va... Rice yield and heading date are two distinct traits controlled by quantitative trait loci (QTLs). The dissection of molecular mechanisms underlying rice yield traits is important for developing high-yielding rice varieties. Here, we report the cloning and characterization of Ghd8, a major QTL with pleiotropic effects on grain yield, heading date, and plant height. Two sets of near isogenic line populations were developed for the cloning of GhdS. Ghd8 was narrowed down to a 20-kb region containing two putative genes, of which one encodes the OsHAP3 subunit of a CCAAT-box binding protein (HAP complex); this gene was regarded as the Ghd8 candidate. A complementary test confirmed the identity and pleiotropic effects of the gene; interestingly, the genetic effect of Ghd8 was dependent on its genetic background. By regulating Ehdl, RFT1, and Hd3a, Ghd8 delayed flowering under long-day conditions, but promoted flowering under short-day conditions. Ghd8 up-regulated MOC1, a key gene controlling tillering and branching; this increased the number of tillers, primary and secondary branches, thus producing 50% more grains per plant. The ectopic expression of Ghd8 in Arabidopsis caused early flowering by 10 d-a situation similar to the one observed by its homolog AtHAP3b, when compared to wild-type under long-day conditions; these findings indicate the conserved function of Ghd8 and AtHAP3b in flowering in Arabidopsis. Our results demonstrated the important roles of Ghd8 in rice yield formation and flowering, as well as its opposite functions in flowering between rice and Arabidopsis under long-day conditions. 展开更多
关键词 Near isogenic lines CCAAT-box binding protein ectopic expression flowering pathway yield formation
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语言资源与语言问题 被引量:101
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作者 陈章太 《云南师范大学学报(哲学社会科学版)》 CSSCI 2009年第4期1-7,共7页
近些年来,我国的"语言资源"热逐渐形成,但有待进一步升温,而过去将语言视为问题的认识正在淡化。其实语言有两重性,既是社会资源,又是麻烦问题,二者总是相伴出现相互转化的,从而促进语言的演变与发展。论文从理论和实际两方面... 近些年来,我国的"语言资源"热逐渐形成,但有待进一步升温,而过去将语言视为问题的认识正在淡化。其实语言有两重性,既是社会资源,又是麻烦问题,二者总是相伴出现相互转化的,从而促进语言的演变与发展。论文从理论和实际两方面,具体论述了语言资源与语言问题的关系和语言资源的形成、分类及其性质转化以及语言问题的构成、表现、转化及其与语言安全的关系。论文还对"语言问题"与"语言安全"作了描述与界定。 展开更多
关键词 语言资源 语言问题 语言安全 形成 表现 转化
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Inhibiting effect of antisense oligonucleotides phosphorthioate on gene expression of TIMP-1 in rat liver fibrosis 被引量:73
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作者 Qing He Nie Yong Qian Cheng Yu Mei Xie Yong Xing Zhou Yi Zhan Cao The Center of Infectious Disease Diagnosis and Treatment of PLA,Tangdu Hospital,Forth Military Medical University,Xi’an 710038,Shaanxi Province,ChinaDr,Qing He Nie graduated from Qinghai Medical College as a doctor in 1983,got master degree at Beijing 302 Army Hospital in 1993,got doctor degree at the Third Military Medical University in 1998,engaged in postdoctoral research at the Fourth Military Medical University from 1998 to 2000,now an associate professor,specialized in clinical and experimental research of infectious diseases,had more than 90 papers published,coauthor of ten books,first author of one book. 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第3期363-369,共7页
AIM: To observe the inhibition of antisense oligonucleotides (asON) phosphorthioate to the tissue inhibitors metalloproteinase-1 (TIMP-1) gene and protein expression in the liver tissue of immunologically induced hepa... AIM: To observe the inhibition of antisense oligonucleotides (asON) phosphorthioate to the tissue inhibitors metalloproteinase-1 (TIMP-1) gene and protein expression in the liver tissue of immunologically induced hepatic fibrosis rats. The possibility of reversing hepatic fibrosis through gene therapy was observed. METHODS: Human serum albumin (HSA) was used to attack rats, as hepatic fibrosis model, in which asONs were used to block the gene and protein expressing TIMP-1. According to the analysis of modulator, structure protein, coding series of TIMP-1 genome, we designed four different asONs. These asONs were injected into the hepatic fibrosis models through coccygeal vein. The results was observed by RT-PCR for measuring TIMP-1 mRNA expression, immunohistochemistry and in situ hybridization for collagen I, II, special staining of collagen fiber, and electron microscopic examination. RESULTS: Hepatic fibrosis could last within 363 days in our modified model. The expressing level of TIMP-1 was high during hepatic fibrosis process. It has been proved by the immunohistochemical and the electron microscopic examination that the asON phosphorthioate of TIMP-1 could exactly express in vivo. The effect of colchicine was demonstrated to inhibit the expressing level of mRNA and the content of collagen I, III in the liver of experimental hepatic fibrosis rats. However, the electron microscopy research and the pathologic grading of hepatic fibrosis showed that there was no significant difference between the treatment group and the model group (P】 0.05). CONCLUSION: The experimental rat model of hepatic fibrosis is one of the preferable models to estimate the curative effect of anti-hepatic fibrosis drugs. The asON phosphorthioate of TIMP-1 could block the gene and protein expression of TIMP-1 in the liver of experimental hepatic fibrosis rats at the mRNA level. It is possible to reverse hepatic fibrosis, and it is expected to study a new drug of antihepatic fibrosis on the genetic level. Colchicine has very limited th 展开更多
关键词 Gene Therapy Animals Collagen Type I Collagen Type III Disease Models Animal Female Gene expression Hepatocytes Immunohistochemistry Liver Liver Cirrhosis Microscopy Electron Oligonucleotides Antisense PROCOLLAGEN RNA Messenger RATS Rats Wistar Research Support Non-U.S. Gov't Tissue Inhibitor of Metalloproteinase-1
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汉英新词翻译:一项费力难讨好的活儿 被引量:65
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作者 杨全红 《中国翻译》 CSSCI 北大核心 2003年第5期70-73,共4页
我国目前的汉英新词翻译可谓成绩不小,问题不少。理解与表达素来是翻译中的两个主要环节,本文即从该二环节入手,对汉英新词翻译中经常出现的问题进行较深入的讨论,文章同时对汉英新词翻译的主要特点进行分析。
关键词 汉语新词 英译 特点 理解 表达
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阿替普酶联合丁苯酞对急性脑梗死的临床疗效及作用机制研究 被引量:71
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作者 程超婵 涂汉明 +3 位作者 应爱娟 徐国强 胡灵芝 潘君枝 《中国临床药理学杂志》 CAS CSCD 北大核心 2015年第23期2293-2296,共4页
目的探讨阿替普酶联合丁苯酞氯化钠注射液对急性脑梗死患者的临床疗效及对其血清应激因子表达的影响。方法 142例急性脑梗死患者随机分为试验组和对照组,各71例。2组均在常规药物基础上给予丁苯酞氯化钠注射液治疗,每次100 m L,每天2次... 目的探讨阿替普酶联合丁苯酞氯化钠注射液对急性脑梗死患者的临床疗效及对其血清应激因子表达的影响。方法 142例急性脑梗死患者随机分为试验组和对照组,各71例。2组均在常规药物基础上给予丁苯酞氯化钠注射液治疗,每次100 m L,每天2次,每次注射时间间隔6 h以上,50~70 min内滴注完毕。试验组在对照组的基础上加用阿替普酶,阿替普酶5 mg溶于0.9%Na Cl10 m L中静脉推注,10 s内推注完毕;其余45 mg溶于100 m L0.9%Na Cl中静脉滴注,60 min内滴注完毕,每天1次。2组疗程均为2周。比较2组的临床疗效及治疗前后神经功能及应激因子表达变化。结果试验组总有效率为95.8%,对照组为83.1%(P〈0.05)。2组患者治疗1,2周后脑梗死体积均显著减小,美国国立卫生院卒中评分(NIHSS)均显著降低,Barthel指数(BI)显著升高(P〈0.05),试验组改善更明显(P〈0.05)。2组患者治疗1,2周后白细胞介素-6(IL-6)、IL-8、IL-10、C-反应蛋白均显著下降(P〈0.05),试验组下降更显著(P〈0.05)。结论阿替普酶联合丁苯酞氯化钠注射液能够明显降低急性脑梗死患者血清应激因子表达水平,控制脑梗死体积,改善神经功能。 展开更多
关键词 阿替普酶 丁苯酞氯化钠 急性脑梗死 应激因子 表达
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纳豆激酶基因的克隆与表达 被引量:43
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作者 张淑梅 张云湖 +3 位作者 赵晓祥 李晶 金红星 田洁萍 《中国生物化学与分子生物学报》 CAS CSCD 1999年第6期912-915,共4页
利用PCR方法从分泌纳豆激酶的枯草杆菌基因组DNA 中扩增得到了纳豆激酶基因,并测定其核苷酸序列.利用基因重组技术构建了纳豆激酶基因的表达载体,并在大肠杆菌中进行了表达.SDS-聚丙烯酰胺凝胶电泳表明,表达蛋白占菌体... 利用PCR方法从分泌纳豆激酶的枯草杆菌基因组DNA 中扩增得到了纳豆激酶基因,并测定其核苷酸序列.利用基因重组技术构建了纳豆激酶基因的表达载体,并在大肠杆菌中进行了表达.SDS-聚丙烯酰胺凝胶电泳表明,表达蛋白占菌体蛋白的15.2% ,琼脂糖-纤维蛋白平板法测出表达产物具有溶解血栓活性. 展开更多
关键词 纳豆激酶基因 序列 表达 克隆 溶栓药
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Analysis of in vivo patterns of caspase 3 gene expression in primary hepatocellular carcinoma and its relationship to p21^(WAF1) expression and hepatic apoptosis 被引量:65
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作者 Bao Hua Sun Jun Zhang Bao JǜWang Xi Ping Zhao You Kun Wang Zhi Qun Yu Dong Liang Yang Lian Jie Hao Department of Clinical Immunology,Tongji Hospital,Tongji Medical University,Wuhan 430030,Hubei Province,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2000年第3期356-360,共5页
AIM To detect the expression of caspase 3gene in primary human hepatocellular carcinoma(HCC)and investigate its relationship to p21<sup>WAF1</sup>gene expression and HCC apoptosis.METHODS In situ hybridi... AIM To detect the expression of caspase 3gene in primary human hepatocellular carcinoma(HCC)and investigate its relationship to p21<sup>WAF1</sup>gene expression and HCC apoptosis.METHODS In situ hybridization was employedto determine caspase 3 and p21<sup>WAF1</sup>expression inHCC.In situ end-labeling was used to detecthepatocytic apoptosis in HCC.RESULTS Twenty-one of 39(53.8%)cases ofHCC were found to express caspase 3transcripts,while 45.2% of HCC failed toexpress caspase 3.Non-cancerous adjacent livertissues showed more positive caspase 3(87.5%,7/8)as compared with HCC(P【0.05).The expression of caspase 3 is correlated withHCC differentiation,72.2%(13/18)ofmoderately to highly differentiated HCC showedcaspase 3 transcripts positive,while only 38.1%of poorly differentiated HCC harbored caspase 3transcripts(P【0.05).No relationship wasfound between caspase 3 expression and tumorsize or grade or metastasis,although 52.5%(5/8)of HCC with metastasis were caspase 3positive and a little higher than that with nometastasis(51.6%,P】0.05).Expression of caspase 3 alone did not affect the apoptosisindex(AI)of HCC.The AI was 7.12%o in caspase3-positive tumors(n=21),while in caspase 3-negative cases(n=18)6.59%0(P】0.05).Expression of caspase 3 clearly segregated withp21<sup>WAF1</sup>positive tumors as compared withp21<sup>WAF1</sup>-negative cases(16 of 23,69.6% versus5 of 16,31.3%)with statistical significance(P=0.017).In the cases with positive caspase 3and negative p21<sup>WAF1</sup>,the Al was found slightlyhigher,but with no statistical significance,thanthat with expression of p21<sup>WAF1</sup>and caspase 3(7.21‰ vs 6.98‰,P】0.05).CONCLUSION Loss of caspase 3 expressionmay contribute to HCC carcinogenesis,althoughthe expression of caspase 3 does not correlatewell with cell apoptosis in HCC.p21<sup>WAF1</sup>may bemerely one of the inhibitors which can reducecaspase 3 mediated cell apoptosis in HCCs. 展开更多
关键词 carcinoma HEPATOCELLULAR CASPASE 3 APOPTOSIS liver NEOPLASMS gene expression
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奉节脐橙果实苯丙氨酸解氨酶活性及其基因表达与果皮褐变的关系 被引量:58
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作者 李正国 高雪 +3 位作者 樊晶 杨迎伍 李道高 Angelos K.Kanellis 《植物生理与分子生物学学报》 CAS CSCD 北大核心 2006年第3期381-386,共6页
柑橘果皮褐变严重影响果实的商品价值和耐贮性。以奉节脐橙(CitrussinensisOsbeck)果实为材料,通过采后常温、涂蜡、低温、机械损伤等处理研究了果实果皮褐变率、苯丙氨酸解氨酶(PAL)活性及PAL基因在果皮褐变过程中表达水平的变化。结... 柑橘果皮褐变严重影响果实的商品价值和耐贮性。以奉节脐橙(CitrussinensisOsbeck)果实为材料,通过采后常温、涂蜡、低温、机械损伤等处理研究了果实果皮褐变率、苯丙氨酸解氨酶(PAL)活性及PAL基因在果皮褐变过程中表达水平的变化。结果表明,涂蜡、损伤处理均极显著地提高果实的果皮褐变率,而低温贮藏可显著降低其发生率;贮藏期间各处理的PAL活性均呈上升趋势,损伤处理PAL活性显著高于对照。果实发生褐变或受到机械损伤后,PAL2、PAL6基因的表达均比对照明显增强。结果首次表明脐橙果实PAL活性变化以及PAL2基因的表达与果皮褐变具有非常密切的关系。 展开更多
关键词 脐橙(Citrus SINENSIS Osbeck) 果皮褐变 苯丙氨酸解氨酶(PAL) PAL基因 表达
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大学校园景观设计中文化内涵的表达 被引量:57
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作者 邱玉华 陈幼琳 《华中科技大学学报(城市科学版)》 CAS 2007年第2期74-77,共4页
大学校园景观文化是校园文化的重要组成部分。大学校园景观文化的表达应以大学文化的内容、学校性质、办学特征、场地的自然和历史文脉为依托,遵循主题性、系统性、生态性、教育性和美学原则,通过植物、建筑、雕塑、园林小品和楹联题刻... 大学校园景观文化是校园文化的重要组成部分。大学校园景观文化的表达应以大学文化的内容、学校性质、办学特征、场地的自然和历史文脉为依托,遵循主题性、系统性、生态性、教育性和美学原则,通过植物、建筑、雕塑、园林小品和楹联题刻等方式表达出来。 展开更多
关键词 景观设计 文化内涵 文脉 表达
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Expression of hepatitis B virus genes in early embryonic cells originated from hamster ova and human spermatozoa transfected with the complete viral genome 被引量:62
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作者 Bahy Ahmed Ali Tian-Hua Huang +1 位作者 Halima-Hassan Salem Qing-Dong Xie 《Asian Journal of Andrology》 SCIE CAS CSCD 2006年第3期273-279,共7页
Aim: To detect the expression of hepatitis B virus (HBV) genes (HB S and C genes) in early embryonic cells after introducing motile human sperm carrying HBV DNA into zona-free hamster oocytes via the in vitro fer... Aim: To detect the expression of hepatitis B virus (HBV) genes (HB S and C genes) in early embryonic cells after introducing motile human sperm carrying HBV DNA into zona-free hamster oocytes via the in vitro fertilization (IVF) technique. Methods: Human sperm-mediated HBV genes were delivered into zona-free hamster oocytes by the IVF method. Polymerase chain reaction (PCR) was used to detect HB S and pre-Core/Core (pre-C/C) coding genes both in one- and two-cell embryos. Reverse transcription-PCR (RT-PCR) analysis was used to study the expression of the two genes. Fluorescence in situ hybridization (FISH) analysis using the full-length HBV DNA as the hybridization probe was performed to confirm the integration of viral DNA in the host embryonic genome. Results: Both HB S and pre-C/C coding genes are present and transcribed in one- and two-cell embryos originated from hamster ova IVF with human spermatozoa carrying HBV DNA sequences. Conclusion: Sperm-mediated HBV genes are able to replicate and express themselves in early embryonic cells. These results provide direct evidence that HBV DNA could transmit vertically to the next generation via the male germ line. 展开更多
关键词 hepatitis B virus gene expression hamster ovary human spermatozoa in vitro fertilization
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溶菌酶的研究进展 被引量:39
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作者 贾向志 李元 马文煜 《生物技术通讯》 CAS 2002年第5期374-377,共4页
溶菌酶在自然界中广泛存在,是一种与单核-巨噬细胞系统有关的非特异防御机制。人溶菌酶在临床上具有潜在的使用价值。由于来源有限,利用基因工程技术从细菌或酵母中生产人溶菌酶实现产业化,是解决其供需矛盾的有效途径。有关溶菌酶抗菌... 溶菌酶在自然界中广泛存在,是一种与单核-巨噬细胞系统有关的非特异防御机制。人溶菌酶在临床上具有潜在的使用价值。由于来源有限,利用基因工程技术从细菌或酵母中生产人溶菌酶实现产业化,是解决其供需矛盾的有效途径。有关溶菌酶抗菌功能以外的其它未知生物学作用,也是当前研究的热点。 展开更多
关键词 溶菌酶 研究进展 模型 基因克隆 表达
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地域文化在城市景观设计中的表达——以吴起城区景观为例 被引量:58
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作者 杨婷 季菲菲 +3 位作者 吉文丽 王诚吉 樊俊喜 唐胜田 《西北林学院学报》 CSCD 北大核心 2013年第3期240-244,共5页
随着各地经济的迅速发展,对地域文化的关注显著增强,城市需要从地域文化中获得经济社会发展的动力,而地域文化景观成为塑造城市特色、促进旅游及城市发展的必然需要。通过对国内外城市地域文化景观的分析,以陕西省吴起县城区景观为例,... 随着各地经济的迅速发展,对地域文化的关注显著增强,城市需要从地域文化中获得经济社会发展的动力,而地域文化景观成为塑造城市特色、促进旅游及城市发展的必然需要。通过对国内外城市地域文化景观的分析,以陕西省吴起县城区景观为例,阐述了地域文化在城市景观设计中的表达方法。首先要挖掘和理解地域文化,结合地域文化特征与城市景观系统要素,使地域文化根植于景观中,达到保护和发展地域文化,塑造地域特色的城市景观的效果。 展开更多
关键词 地域文化 表达 景观 吴起
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浅议西方茶文化及英语“茶”语 被引量:56
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作者 兰冰 《曲靖师范学院学报》 2011年第1期118-121,共4页
茶在16世纪从中国传入欧洲,由上流社会的奢侈品逐渐成为平民的饮品,成为西方人必不可少的饮料。茶特有的多种功能使西方人爱上饮茶,并把中国的茶文化融入了西方的习俗,形成了自己特有的茶文化。英语Tea源于厦门方言的发音,进入英语后,... 茶在16世纪从中国传入欧洲,由上流社会的奢侈品逐渐成为平民的饮品,成为西方人必不可少的饮料。茶特有的多种功能使西方人爱上饮茶,并把中国的茶文化融入了西方的习俗,形成了自己特有的茶文化。英语Tea源于厦门方言的发音,进入英语后,产生了许多与茶相关的茶事、茶饮词汇,丰富了英语语言。由Tea产生的习语含义简洁,喻意深刻,在词义上,Tea还出现了引申及转义现象。 展开更多
关键词 西方茶文化 词语 表达
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桃ACC氧化酶基因的克隆和植物表达载体的构建 被引量:17
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作者 金勇丰 张耀洲 +1 位作者 陈大明 张上隆 《园艺学报》 CAS CSCD 北大核心 1998年第1期37-43,共7页
以‘玉露’桃叶片基因组DNA为模板,用ACC氧化酶基因特异寡聚核苷酸为引物进行PCR扩增,得到1.3kb左右的扩增产物,将其克隆到pUC19加T载体上,组建亚克隆并进行序列测定,结果表明,该基因全长有1288个碱基,... 以‘玉露’桃叶片基因组DNA为模板,用ACC氧化酶基因特异寡聚核苷酸为引物进行PCR扩增,得到1.3kb左右的扩增产物,将其克隆到pUC19加T载体上,组建亚克隆并进行序列测定,结果表明,该基因全长有1288个碱基,由4个外显子和3个内含子组成。外显子由957碱基组成,编码319个氨基酸。该基因与桃、番茄、矮牵牛、康乃馨、苹果ACC氧化酶cDNA氨基酸序列同源性分别为99.3%,83.0%,76.8%,74.0%,75.0%。RNA点杂交表明,该基因在未成熟果实检测不到杂交信号,随着成熟度增加,硬度下降,基因表达增强。将ACC氧化酶基因分别正向和反向克隆到植物表达载体pBI121中,并通过酶切分析,PCR和点杂交鉴定重组质粒正确。将重组表达质粒导入根癌农杆菌中,经PCR和Southern杂交鉴定证实质粒已被导入。 展开更多
关键词 桃树 ACC 氧化酶基因 克隆 基因表达
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Narrowing Down the Targets: Towards Successful Genetic Engineering of Drought-Tolerant Crops 被引量:52
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作者 Shujun Yang Barbara Vanderbeld Jiangxin Wan Yafan Huang 《Molecular Plant》 SCIE CAS CSCD 2010年第3期469-490,共22页
Drought is the most important environmental stress affecting agriculture worldwide. Exploiting yield potential and maintaining yield stability of crops in water-limited environments are urgent tasks that must be under... Drought is the most important environmental stress affecting agriculture worldwide. Exploiting yield potential and maintaining yield stability of crops in water-limited environments are urgent tasks that must be undertaken in order to guarantee food supply for the increasing world population. Tremendous efforts have been devoted to identifying key regulators in plant drought response through genetic, molecular, and biochemical studies using, in most cases, the model species Arabidopsis thaliana. However, only a small portion of these regulators have been explored as potential candidate genes for their application in the improvement of drought tolerance in crops. Based on biological functions, these genes can be classified into the following three categories: (1) stress-responsive transcriptional regulation (e.g. DREB1, AREB, NF-YB); (2) post-transcriptional RNA or protein modifications such as phosphorylation/dephosphorylation (e.g. SnRK2, ABI1) and farnesylation (e.g. ERA1); and (3) osomoprotectant metabolism or molecular chaperones (e.g. CspB). While continuing down the path to discovery of new target genes, serious efforts are also focused on fine-tuning the expression of the known candidate genes for stress tolerance in specific temporal and spatial patterns to avoid negative effects in plant growth and development. These efforts are starting to bear fruit by showing yield improvements in several crops under a variety of water-deprivation conditions. As most such evaluations have been performed under controlled growth environments, a gap still remains between early success in the laboratory and the application of these techniques to the elite cultivars of staple crops in the field. Nevertheless, significant progress has been made in the identification of signaling pathways and master regulators for drought tolerance. The knowledge acquired will facilitate the genetic engineering of single or multiple targets and quantitative trait loci in key crops to create commercialrade cultiv 展开更多
关键词 Abiotic stress drought tolerance gene expression genetic engineering crop yield potential field trials.
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Multiple genetic alterations and behavior of cellular biology in gastric cancer and other gastric mucosal lesions:H.pylori infection,histological types and staging 被引量:52
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作者 Heng Jun Gao Lian Zhen Yu +7 位作者 Jian Feng Bai Yan Shen Peng Gu Sun Han Lin Zhao Kun Miu Xiu Zhen Lü Xiao Yong Zhang Zhi Quan Zhao 《World Journal of Gastroenterology》 SCIE CAS CSCD 2000年第6期848-854,共7页
AIM To investigate the expression of multiplegenes and the behavior of cellular biology ingastric cancer(GC)and other gastric mucosallesions and their relations to Helicobacter pylori(H.pylori)infection,tumor stag... AIM To investigate the expression of multiplegenes and the behavior of cellular biology ingastric cancer(GC)and other gastric mucosallesions and their relations to Helicobacter pylori(H.pylori)infection,tumor staging andhistological subtypes.METHODS Three hundred and twenty-sevenspecimens of gastric mucosa obtained viaendoscopy or surgical resection,and ABCimmunohistochemical staining were used todetect the expression of p53,p16,Bcl-2 andCOX-2 proteins.H.pylori was determined byrapid urea test combined with pathologicalstaining or<sup>14</sup>C urea breath test.Cellular image analysis was performed in 66 patients withintestinal metaplasia(IM)and/or dysplasia(Dys).In 30 of them,both cancer and theparacancerous tissues were obtained at the timeof surgery.Histological pattern,tumor staging,lymph node metastasis,grading ofdifferentiation and other clinical data werestudied in the medical records.RESULTS p16 expression of IM or Dys wassignificantly lower in positive H.pylori chronicatrophic gastritis(CAG)than those withnegative H.pylori(CAG:54.8% vs 88.0%,IM:34.4% vs 69.6%,Dys:23.8% vs 53.6%,allP【0.05),Bcl-2 or COX-2 expression of IM orDys in positive H.pylori cases was significantlyhigher than that without H.pylori(Bcl-2:68.8%vs23.9%,90.5% vs 60.7%;COX-2:50.0% vs10.8%,61.8% vs 17.8%;all P【0.05).Themean number of most parameters of cellularimage analysis in positive H.pylori group wassignificantly higher than that in negative H.pylori group(Ellipser:53±14,40±12μm,Area<sub>1</sub>:748±572,302±202 μm<sup>2</sup>,Area<sub>2</sub>:3050±1661,1681±1990 μm<sup>2</sup>,all P【0.05;Ellipseb:79±23,58±15 μm,Ratio<sub>1</sub>:22%±5%,13%±4%,Ratio<sub>2</sub>:79%±17%,53%±20%,all P【0.01).There was significant correlation between Bcl-2and histologic pattern of gastric carcinoma,andbetween COX-2 and tumor staging or lymph nodemetastasis(Bcl-2:75.0% vs 16.7%;COX-2:76.0% vs 20.0%,79.2% vs 16.7%;allP【0.05).CONCLUSION p1l6, Bcl-2, and COX-2 but not p53 gene may play a role 展开更多
关键词 stomach neoplasms gastric mucosa/injuries PRECANCEROUS conditions gene expression HELICOBACTER pylori GASTROSCOPY immunohistochemistry neoplasm STAGING
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Expression of the SARS-CoV-2 cell receptor gene ACE2 in a wide variety of human tissues 被引量:53
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作者 Meng-Yuan Li Lin Li +1 位作者 Yue Zhang Xiao-Sheng Wang 《Infectious Diseases of Poverty》 SCIE 2020年第2期23-29,共7页
Background:Since its discovery in December 2019,severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has infected more than 2180000 people worldwide and has caused more than 150000 deaths as of April 16,2020.SAR... Background:Since its discovery in December 2019,severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has infected more than 2180000 people worldwide and has caused more than 150000 deaths as of April 16,2020.SARS-CoV-2,which is the virus causing coronavirus disease 2019(COVID-19),uses the angiotensin-converting enzyme 2(ACE2)as a cell receptor to invade human cells.Thus,ACE2 is the key to understanding the mechanism of SARS-CoV-2 infection.This study is to investigate the ACE2 expression in various human tissues in order to provide insights into the mechanism of SARS-CoV-2 infection.Methods:We compared ACE2 expression levels across 31 normal human tissues between males and females and between younger(ages≤49 years)and older(ages>49 years)persons using two-sided Student's t test.We also investigated the correlations between ACE2 expression and immune signatures in various tissues using Pearson's correlation test.Results:ACE2 expression levels were the highest in the small intestine,testis,kidneys,heart,thyroid,and adipose tissue,and were the lowest in the blood,spleen,bone marrow,brain,blood vessels,and muscle.ACE2 showed medium expression levels in the lungs,colon,liver,bladder,and adrenal gland.ACE2 was not differentially expressed between males and females or between younger and older persons in any tissue.In the skin,digestive system,brain,and blood vessels,ACE2 expression levels were positively associated with immune signatures in both males and females.In the thyroid and lungs,ACE2 expression levels were positively and negatively associated with immune signatures in males and females,respectively,and in the lungs they had a positive and a negative correlation in the older and younger groups,respectively.Conclusions:Our data indicate that SARS-CoV-2 may infect other tissues aside from the lungs and infect persons with different sexes,ages,and races equally.The different host immune responses to SARS-CoV-2 infection may partially explain why males and females,young and old persons infected with this vi 展开更多
关键词 SARS-CoV-2 COVID-19 SARS-CoV-2 cell receptor Angiotensin-converting enzyme 2 Gene expression SARS-CoV-2 pandemic Immune signatures
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山羊β-酪蛋白基因启动子指导的转基因小鼠乳汁高效表达人凝血因子Ⅸ 被引量:35
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作者 黄赞 颜景斌 +4 位作者 黄缨 孙琼 肖艳萍 黄英 曾溢滔 《Acta Genetica Sinica》 SCIE CAS CSCD 北大核心 2002年第3期206-211,T001,共7页
为探讨应用转基因动物乳腺生物反应器高效表达人凝血因子IX(humanclottingfactorIX ,hFIX)的可行性 ,构建了包括山羊 β 酪蛋白基因启动子和外显子 1、内含子 1、外显子 2共约 6 .7kb片段以及hFIX全长cDNA序列和部分经改造的内含子 1的... 为探讨应用转基因动物乳腺生物反应器高效表达人凝血因子IX(humanclottingfactorIX ,hFIX)的可行性 ,构建了包括山羊 β 酪蛋白基因启动子和外显子 1、内含子 1、外显子 2共约 6 .7kb片段以及hFIX全长cDNA序列和部分经改造的内含子 1的乳腺表达载体 ,通过转基因技术获得 12个原代转基因小鼠 (9♀ ,3♂ ) ,整合率为 11.2 %。经ELISA和Westernblot鉴定 8只转基因母鼠乳汁中有hFIX的表达并拥有很高的凝血活性 ,其中一只的表达量高达5 2 .9mg/L ,其凝血活性亦高达 2 79.2 %。FISH实验表明不同的转基因小鼠外源基因整合于小鼠的不同染色体上。结果证明所构建的山羊 β 酪蛋白基因启动子乳腺表达载体能有效指导hFIX基因在小鼠乳腺中高效表达 ,并能保持hFIX的生物活性。 展开更多
关键词 山羊 β-酪蛋白基因启动子 人凝血因子Ⅸ 转基因小鼠 表达
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