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Difference of Gene Expression Profiles between Barrett’s Esophagus and Cardia Intestinal Metaplasia by Gene Chip
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作者 常英 刘斌 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2006年第3期311-313,共3页
The difference of gene expression profile changes in Barrett's esophagus (BE) and cardia intestinal metaplasia (CIM) epithelium was studied and the novel associated genes were screened in the early stage by cDNA ... The difference of gene expression profile changes in Barrett's esophagus (BE) and cardia intestinal metaplasia (CIM) epithelium was studied and the novel associated genes were screened in the early stage by cDNA microarray. The cDNA retro-transcribed from equal quantity mRNA from BE and CIM epithelial tissues were labeled with Cy3 and Cy5 fluorescence as probes. The mixed probe was hybridized with three pieces BiostarH-40s double dot human whole gene chip. The chips were scanned with a ScanArray 4000. The acquired images were analyzed using GenePix Pro 3.0 software. It was found a total of 141 genes were screened out that exhibited differentially expression more than 2 times in all three chips. It was identified that in gene expression profiles of BE, 74 genes were up-regulated and 67 down-regulated as compared with CIM. The comparison between the difference of gene expression profile changes in BE and CIM epithelia revealed that there existed the difference between BE and CIM at gene level. 141 genes with the expression more than two time were probably related to the occurrence and development of BE and the promotion or progress in adenocarcinoma. 展开更多
关键词 Barrett's esophagus cardia intestinal metaplasia gene expression profile
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Correlation between the gene expression profiles of adenocarcinoma of esophagus and Barrett’s esophagus
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作者 Xuqun Huang Hui Zeng 《The Chinese-German Journal of Clinical Oncology》 CAS 2010年第1期26-30,共5页
Objective: The aim of this study was to investigate the characteristics of gene changes from Barrett's esophagus (BE) to esophageal adenocarcinoma by cDNA microarray. Methods: The cDNA retro-transcribed from equa... Objective: The aim of this study was to investigate the characteristics of gene changes from Barrett's esophagus (BE) to esophageal adenocarcinoma by cDNA microarray. Methods: The cDNA retro-transcribed from equal quantity mRNA from esophageal carcinoma and BE tissues as well as control normal epithelium of esophagus which were from one patient with esophageal adenocarcinoma were labeled with Cy5 and Cy3 fluorescence as probes. The mixed probes were hybridized with two pieces gene chip respectively. It was scanned by laser scanner Scan Array 4000. The acquired images were analyzed by software GenePix Pro 3.0. Results: A total of 214 genes were screened out which expression levels were more than 2 times in hybridization of esophageal adenocarcinoma vs normal epithelium of esophagus, whereas 90 genes in hybridization of BE vs normal epithelium. A parallel comparison among these two gene profiles showed that a total of 45 genes with 24 downregulation and 21 up-regulation which expression levels were more than 2 times between the BE and the esophageal adenocarcinoma. Among these, there were 27 genes with 18 downregulafion and 9 up-regulation which implicated the tendencies progressing from BE to esophageal adenocarcinoma. Conclusion: These genes or their products which implicate the tendencies can be chosen as indicators of carcinogenesis with high risk index for BE. 展开更多
关键词 Barrett's esophagus (BE) esophageal adenocarcinoma gene expression profile
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Depth Profile Study of Electroless Deposited Sb2S3 Thin Films Using XPS for Photovoltaic Applications
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作者 Towhid Adnan Chowdhury 《Materials Sciences and Applications》 2023年第7期397-406,共10页
Sb<sub>2</sub>S<sub>3</sub> has gained tremendous research recently for thin film solar cell absorber material because of their easy synthesis, unique electrical and optical properties. The sto... Sb<sub>2</sub>S<sub>3</sub> has gained tremendous research recently for thin film solar cell absorber material because of their easy synthesis, unique electrical and optical properties. The stoichiometry and composition of electroless Sb<sub>2</sub>S<sub>3</sub> thin films were analyzed using XPS depth profile studies. The surface layers were found nearly stoichiometric. On the other hand, the inner layer was rich in antimony composition making it more conductive electrically. 展开更多
关键词 sb<sub>2sub>s<sub>3sub> Depth profiling X-Ray Photoelectron spectroscopy Thin Film ELECTROLEss
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Kerogen Kinetic Distributions and Simulations Provide Insights into Petroleum Transformation Fraction (TF) Profiles of Organic-Rich Shales
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作者 David A.Wood 《Journal of Earth Science》 SCIE CAS CSCD 2024年第3期747-757,共11页
Two hundred and fifty single first-order Arrhenius reactions are simulated to generate S2 pyrograms at three heating rates 25,15,and 5°C·min-1.The activation energy(E)and pre-exponential factor(A)of the reac... Two hundred and fifty single first-order Arrhenius reactions are simulated to generate S2 pyrograms at three heating rates 25,15,and 5°C·min-1.The activation energy(E)and pre-exponential factor(A)of the reactions simulated follow a long-established trend of those variable values displayed by shales and kerogens.The characteristics of the transformation fraction(TF)profiles(product generation window temperatures)of the simulated single reactions are compared to the TF profiles of recorded shale pyrograms generated by multiple reactions with different E-A values lying near the defined E-A trend.Important similarities and differences are observed between the TF profile values of the two datasets.The similarities support the spread of E-A values involved in shale pyrogram best fits.The differences are most likely explained by the complexity of the multiple kerogen first-order and second-order reactions contributing to the recorded shale pyrograms versus the simplicity and crispness of the single first-order reactions simulated.The results also justify the validity of using the previously described“variable E-A pyrogram-fitting method”of multi-heating-rate shale pyrograms enabling optimizers to choose multiple reactions from an unlimited range of E-A values.In contrast,further doubt is cast on the validity of the constant-A pyrogram-fitting method used by the Easy%Ro technique,in that a distribution of reactions with a single A value is unlikely to represent the complex variety of kerogen macerals observed in shale formations.TF profiles generated by the variable E-A pyrogram-fitting method lie close to the established E-A trend and are likely to provide more realistic TF generation window temperatures than TF profiles generated by the constant-A pyrogram-fitting method. 展开更多
关键词 transformation fraction profiles simulated s2 pyrograms multiple heating rates kerogen/shale kinetics s2 pyrogram fitting techniques KEROGEN petroleum research.
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Simulation of wheel and rail profile wear:a review of numerical models 被引量:3
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作者 N.Bosso M.Magelli N.Zampieri 《Railway Engineering Science》 2022年第4期403-436,共34页
The development of numerical models able to compute the wheel and rail profile wear is essential to improve the scheduling of maintenance operations required to restore the original profile shapes.This work surveys th... The development of numerical models able to compute the wheel and rail profile wear is essential to improve the scheduling of maintenance operations required to restore the original profile shapes.This work surveys the main numerical models in the literature for the evaluation of the uniform wear of wheel and rail profiles.The standard structure of these tools includes a multibody simulation of the wheel-track coupled dynamics and a wear module implementing an experimental wear law.Therefore,the models are classified according to the strategy adopted for the worn profile update,ranging from models performing a single computation to models based on an online communication between the dynamic and wear modules.Nevertheless,the most common strategy nowadays relies on an iteration of dynamic simulations in which the profiles are left unchanged,with co-simulation techniques often adopted to increase the computational performances.Work is still needed to improve the accuracy of the current models.New experimental campaigns should be carried out to obtain refined wear coefficients and models,while strategies for the evaluation of both longitudinal and transversal wear,also considering the effects of tread braking,should be implemented to obtain accurate damage models. 展开更多
关键词 WEAR Wheel and rail profiles wheel-rail contact Railway vehicle dynamics Multibody simulation CO-sIMULATION
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Gut microbiome profiling and colorectal cancer in African Americans and Caucasian Americans 被引量:5
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作者 Lulu Farhana Fadi Antaki +6 位作者 Farhan Murshed Hamidah Mahmud Stephanie L Judd Pratima Nangia-Makker Edi Levi Yingjie Yu Adhip PN Majumdar 《World Journal of Gastrointestinal Pathophysiology》 CAS 2018年第2期47-58,共12页
AIM To determine whether and to what extent the gut microbiome is involved in regulating racial disparity in colorectal cancer(CRC). METHODS All patients were recruited and experiments were performed in accordance wit... AIM To determine whether and to what extent the gut microbiome is involved in regulating racial disparity in colorectal cancer(CRC). METHODS All patients were recruited and experiments were performed in accordance with the relevant guidelines and regulations by the Institutional Review Boards (IRB), committees of the John D. Dingell VAMC and Wayne State University guidelines. African American (AA) and Caucasian American (CA) patients were scheduled for an outpatient screening for colonoscopy, and no active malignancy volunteer patients were doubly consented, initially by the gastroenterologist and later by the study coordinator, for participation in the study. The gut microbial communities in colonic effluents from AAs and CAs were examined using 16 sRNA profiling, and bacterial identifications were validated by performing SYBR-based Real Time PCR. For metagenomic analysis to characterize the microbial communities, multiple software/tools were used, including Metastats and R statistical software.RESULTS It is generally accepted that the incidence and mortality of CRC is higher in AAs than in CAs. However, the reason for this disparity is not well understood. We hypothesize that the gut microbiome plays a role in regulating this disparity. Indeed, we found significant differences in species richness and diversity between AAs and CAs. Bacteroidetes was more abundant in AAs than in CAs. In particular, the pro-inflammatory bacteria Fusobacterium nucleatum and Enterobacter species were significantly higher in AAs, whereas probiotic Akkermansia muciniphila and Bifidobacterium were higher in CAs. The polyphyletic Clostridia class showed a divergent pattern, with Clostridium XI elevated in AAs, and Clostridium IV, known for its beneficial function, higher in CAs. Lastly, the AA group had decreased microbial diversity overall in comparison to the CA group. In summary, there were significant differences in pro-inflammatory bacteria and microbial diversity between AA and CA, which may help explain the CRC disparity between groups.CONCLUSION Our current investigation, for the first time, demonstrates microbial dysbiosis between AAs and CAs, which could contribute to the racial disparity of CRC. 展开更多
关键词 Human GUT MICROBIOME Colorectal cancer FUsOBACTERIUM nucleatum African AMERICANs 16s RNA profilING METAGENOMICs
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Typical Equilibrium Beach Profile Models and Their Significances from Different Segments of A Headland-Bay Beach 被引量:1
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作者 于吉涛 丁圆婷 +2 位作者 程璜鑫 李志强 陈子燊 《China Ocean Engineering》 SCIE EI CSCD 2016年第4期637-650,共14页
This study introduces three typical models on equilibrium beach profile, and discusses the application limitations of these models. Then this study examines the selections for applying these models on different coasta... This study introduces three typical models on equilibrium beach profile, and discusses the application limitations of these models. Then this study examines the selections for applying these models on different coastal segments of a headland-bay beach in west Guangdong, South China, and explores the physical significances of those parameters in the models. The results indicate that:(1) Bodge's model is more in line with the equilibrium beach profile of the tangential or transitional segment, whereas Lee's model is more consistent with the shadow profile;(2) most of the parameters in three models have clear physical significances in accordance with the actual characteristics of this headland-bay beach; and(3) both the selections for the equilibrium beach profile from different segments and significances of most of the parameters in three models are in essence correlated with the morphodynamic states at various coastal locations. 展开更多
关键词 equilibrium beach profile Bruun/Dean's model Bodge's model Lee's model parameter significances headland-bay beach
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Analysis of hippocampal gene expression profile of Alzheimer's disease model rats using genome chip bioinformatics 被引量:1
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作者 Yinghong Li Zhengzhi Wu +5 位作者 Yu Jin Anmin Wu Meiqun Cao Kehuan Sun Xiuqin Jia Manyin Chen 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第5期332-340,共9页
In this study, an Alzheimer's disease model was established in rats through stereotactic injection of condensed amyloid beta 1-40 into the bilateral hippocampus, and the changes of gene expression profile in the hipp... In this study, an Alzheimer's disease model was established in rats through stereotactic injection of condensed amyloid beta 1-40 into the bilateral hippocampus, and the changes of gene expression profile in the hippocampus of rat models and sham-operated rats were compared by genome expression profiling analysis. Results showed that the expression of 50 genes was significantly up-regulated (fold change 〉 2), while 21 genes were significantly down-regulated in the hippocampus of Alzheimer's disease model rats (fold change 〈 0.5) compared with the sham-operation group. The differentially expressed genes are involved in many functions, such as brain nerve system development, neuronal differentiation and functional regulation, cellular growth, differentiation and apoptosis, synaptogenesis and plasticity, inflammatory and immune responses, ion channels/transporters, signal transduction, cell material/energy metabolism. Our findings indicate that several genes were abnormally expressed in the metabolic and signal transduction pathways in the hippocampus of amyloid beta 1 40-induced rat model of Alzheimer's disease, thereby affecting the hippocampal and brain functions. 展开更多
关键词 amyloid beta 1-40 Alzheimer's disease HIPPOCAMPUs genome chip gene expression profile neural regeneration
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Judgement and interpretation of S-wave data on the Beijing-Fengzhen DSS profile
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作者 宋松岩 周雪松 +3 位作者 张先康 邱淑燕 龚怡 宋建立 《Acta Seismologica Sinica(English Edition)》 EI CSCD 1998年第1期68-77,共10页
By use of S wave information from three component records of wide angle reflection/refraction Beijing Fengzhen DSS profile (340.0 km) and its adjacent area, several main S wave phases (wave groups) of the crust a... By use of S wave information from three component records of wide angle reflection/refraction Beijing Fengzhen DSS profile (340.0 km) and its adjacent area, several main S wave phases (wave groups) of the crust and the top of upper mantle have been picked up and identified with digital processing technique. With reference to the results from P wave interpretation, 2 D structures, including S wave velocity vS and Poisson ratio μ , are calculated. After a comprehensive study with information from near vertical reflection, geology and other geophysical explorations, the deep structural configuration of this region is presented and relevant inferences are drawn from the above result: crustal thickness along the profile tends to increase westwards, from 35.0 km at Shunyi to 42.0 km at Fengzhen; there exist three low velocity bodies in the lower crust east of Yanqing, in the middle crust below Yanqing Zhuolu and in the upper crust west of Tianzhen, respectively; from east to west, there is also a crust mantle transitional zone about 5.0~9.0 km thick; in most parts of the region, μ value is 0.25 in the upper and middle crust, 0.27 in the lower crust and 0.28 on top of the upper mantle, indicating that the upper and middle crust is characterized by brittleness, and the lower crust and top of upper mantle is characterized by ductility; between Yanqing Zhuolu, the low μ values of the upper crust suggest that cracks (or pores) grow in the rock masses which present a dry (or gas filled) state, while the high μ values in the middle crust may reflect a fluid filled (or partially fusion) state of the rock masses. On the basis of the characteristics of phases and lateral variation features of μ values, several deep seated faults in this region are ascertained. Most earthquakes occurred near these faults where μ values vary significantly, and concentrate in the brittle rock masses with low μ values. 展开更多
关键词 Yanqing Huailai basin Dss profile s wave μ value ultra crustal fault
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A search for evidence of small-scale inhomogeneities in dense cores from line profile analysis
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作者 Lev Pirogov 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2018年第8期97-102,共6页
In order to search for intensity fluctuations on the HCN(1-0) and HCO+(1-0) line pro- files, which could arise due to possible small-scale inhomogeneous structure, long-term observations of high-mass star-forming... In order to search for intensity fluctuations on the HCN(1-0) and HCO+(1-0) line pro- files, which could arise due to possible small-scale inhomogeneous structure, long-term observations of high-mass star-forming cores S140 and S199 were carried out. The data were processed by the Fourier filtering method. Line temperature fluctuations that exceed the noise level were detected. Assuming the cores consist of a large number of randomly moving small thermal fragments, the total number of frag- ments is - 4 × 106 for the region with linear size - 0.1 pc in S140 and - 106 for the region with linear size - 0.3 pc in S 199. Physical parameters of fragments in S 140 were obtained from detailed modeling of the HCN emission in the framework of the clumpy cloud model. 展开更多
关键词 LINEs profiles - molecular data - methods data analysis - IsM clouds - IsM molecules - IsM structure - IsM individual objects s 140)
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Oligomicroarray-based primary study of gene expression profile changes in Barrett’s esophagus
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作者 Wang Xingwei Sun Yonggang +3 位作者 Xu Mei Fang Dianchun Gao Hengjun Xu Jiangtao 《Journal of Medical Colleges of PLA(China)》 CAS 2008年第5期251-257,共7页
Objective: To analyze the differential expression genes (DEGs) between Barrett’s esophagus (BE) and normal esophagus mucosa and explore the target genes related to the development and progression of BE. Methods: The ... Objective: To analyze the differential expression genes (DEGs) between Barrett’s esophagus (BE) and normal esophagus mucosa and explore the target genes related to the development and progression of BE. Methods: The total RNAs of matched BE and normal esophagus mucosa of BE patients were isolated using one step Trizol method. Matched RNAs were qualified using 10 g/L agarose gel electrophoresis. cRNAs were synthesized, fluorescence labeled and purified after total RNAs were purified. The RNAs of BE and normal esophagus mucosa were hybridized with Agilent oligomicroarray (30 968 probes). The fluorescence intensity features were detected by Agilent scanner and quantified by feature extraction software. Results: (1) The total RNA, reverse transcription product and fluorescence labeled cRNA were all of high quality; (2) There were 142 up-regulated genes and 284 down-regulated genes among 2-fold DEGs. Conclusion: Microarray-based studies are feasible in endoscopically obtained tissues. Many BE-associated genes are screened by the high-throughput gene chip. The development and progression of BE is a complicated process involving multiple genes and multiple procedures, and functional study of these genes may help to identify the key genes or pathways involved in the pathogenesis and development of BE. 展开更多
关键词 Barrett's esophagus Oligomicroarray Differential expression Gene expression profile
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基于深反射数据的多道面波成像揭示申扎裂谷浅层S波速度结构
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作者 蔡玉国 卢占武 +5 位作者 李文辉 王光文 陈司 程永志 吴国炜 蔡蔚 《矿产勘查》 2023年第10期1988-1998,共11页
青藏高原普遍发育的南北向裂谷对认识青藏高原陆内造山过程和变形机制,探讨岩浆活动、成矿成藏机制具有重要的意义。位于青藏高原南部的申扎裂谷,发育在班公—怒江缝合带和雅江缝合带之间,垂直切割了冈底斯成矿带。本文针对申扎裂谷地... 青藏高原普遍发育的南北向裂谷对认识青藏高原陆内造山过程和变形机制,探讨岩浆活动、成矿成藏机制具有重要的意义。位于青藏高原南部的申扎裂谷,发育在班公—怒江缝合带和雅江缝合带之间,垂直切割了冈底斯成矿带。本文针对申扎裂谷地震波信号弱、干扰强、频率变化大的特点,利用多道面波成像方法处理申扎裂谷及其邻区的81 km深地震反射剖面数据,获得了高质量的S波速度剖面。结合已有地质、地球物理资料对S波速度结构进行解释,重点研究了申扎地区的沉积层厚度以及S波高速异常特征,探讨了申扎裂谷的延伸情况,分析了浅部矿产分布与断裂的关系,讨论了热泉形成的可能成因,获得以下认识:申扎裂谷处的沉积厚度约1000 m;在剖面0~30 km范围下方1000 m以下有成矿潜力;热泉的存在印证了高温岩体的存在,为热液成矿提供了证据。 展开更多
关键词 申扎裂谷 s波速度结构 沉积层 多道面波成像 深地震反射剖面数据
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S型齿廓齿轮滚铣2步加工技术研究
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作者 田宇宙 孙强 吴建伟 《石家庄铁道大学学报(自然科学版)》 2023年第3期119-126,共8页
S型齿廓齿轮的提出,理论上解决了少齿数齿轮传动的问题。针对其加工理论,阐述了一种通用型滚铣2步加工方法:第1步在不产生过切和最大化去除余量的原则下,对齿坯进行滚齿加工,得到了变位渐开线齿轮;第2步基于曲面法向等距曲面的数学理论... S型齿廓齿轮的提出,理论上解决了少齿数齿轮传动的问题。针对其加工理论,阐述了一种通用型滚铣2步加工方法:第1步在不产生过切和最大化去除余量的原则下,对齿坯进行滚齿加工,得到了变位渐开线齿轮;第2步基于曲面法向等距曲面的数学理论,得到了铣削刀具的中心轨迹坐标,分别应用于齿轮的齿侧、齿顶及齿根过渡圆弧,得到了完整的铣削模型,最终获得S型齿廓齿轮的高效加工方法。进行了案例分析及基于三维软件的仿真加工,验证了数学模型的正确性与加工方法的可行性,为后续S型齿廓齿轮实物加工及传动试验分析奠定了基础。 展开更多
关键词 s型齿廓齿轮 滚铣加工 法向等距曲面 仿真加工
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变速箱S形齿廓传动齿轮对整车NVH性能的影响
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作者 李新强 俞晓璇 +1 位作者 陈付贵 程祥峰 《内燃机与动力装置》 2023年第1期89-92,共4页
为降低变速箱的振动噪声,提高整车噪声、振动与声振粗糙度(noise vibration harshness,NVH)性能,通过变速箱下线台架(end of line,EOL)振动测试和整车NVH测试,对比分析正常齿廓齿轮、带S形齿廓的齿轮对整车NVH性能的影响。EOL测试结果表... 为降低变速箱的振动噪声,提高整车噪声、振动与声振粗糙度(noise vibration harshness,NVH)性能,通过变速箱下线台架(end of line,EOL)振动测试和整车NVH测试,对比分析正常齿廓齿轮、带S形齿廓的齿轮对整车NVH性能的影响。EOL测试结果表明:装配S形齿廓齿轮的变速箱的振动加速度级明显高于正常齿廓齿轮变速箱,尤其在48阶次处增幅最大。整车NVH测试结果表明,S形齿廓齿轮在发动机舱及车内的声压级分别增大12、7 dB。实际加工制造验证结果表明,正确设定齿轮加工珩磨轮寿命可以有效消除齿廓的S形波动,改善变速箱及整车的NVH性能。 展开更多
关键词 s形齿轮齿廓 EOL测试 整车NVH测试 声压级 振动噪音
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糜子SAMS基因的克隆及其在干旱复水中的表达模式分析 被引量:22
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作者 林凡云 王士强 +1 位作者 胡银岗 何蓓如 《作物学报》 CAS CSCD 北大核心 2008年第5期777-782,共6页
以糜子抗旱节水研究中获得的一个与S-腺苷甲硫氨酸合成酶(SAMS)基因同源性较高的EST序列为基础,采用RT-PCR技术从糜子中分离到一个SAMS基因的全长cDNA序列(命名为PmSAMS),全长1293bp,编码396个氨基酸,具有SAMS典型的N端结构域、中... 以糜子抗旱节水研究中获得的一个与S-腺苷甲硫氨酸合成酶(SAMS)基因同源性较高的EST序列为基础,采用RT-PCR技术从糜子中分离到一个SAMS基因的全长cDNA序列(命名为PmSAMS),全长1293bp,编码396个氨基酸,具有SAMS典型的N端结构域、中间结构域及C端结构域。糜子、马铃薯、拟南芥、甜菜、大麦、荔枝、番茄和水稻8种植物SAMS的氨基酸序列多重比较分析表明,不同植物的SAMS的氨基酸相似程度非常高(92%~97%),其中糜子与水稻的相似性最高(97%),说明SAMS基因在植物进化中非常保守。PmSAMS基因在糜子幼苗干旱及复水过程中的半定量RT-PCR表达模式分析表明,在干旱早期(土壤含水量36%)诱导该基因大量表达,而干旱程度更严重时(土壤含水量为24%)其表达受到严重抑制,表达量比对照还低;严重干旱后复水2h,其表达量增强至干旱早期的表达量,而复水6h后表达量降低至对照(干旱处理前)水平。可见,PmSAMS基因的表达涉及糜子响应干旱胁迫及干旱后复水过程,可能是糜子抗旱节水的关键基因。该基因的克隆为进一步探讨其应用于农作物抗旱节水性的遗传改良奠定了基础。 展开更多
关键词 糜子 s-腺苷甲硫氨酸合成酶 干旱复水 表达模式 进化分析
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大别造山带地壳S波速度结构 被引量:43
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作者 王椿镛 丁志峰 +3 位作者 宋建立 吴庆举 郑继才 张小兵 《地球物理学报》 SCIE EI CAS CSCD 北大核心 1997年第3期337-346,共10页
在大别造山带深地震测深剖面H维P波地壳速度结构的基础上,从地震记录的水平分量得到S波地壳速度结构,并用P波和S波的资料共同约束地壳的组成.剖面上大多数炮点的记录均显示了清晰的Sg和SmS震相.在埠塔寺炮和金拱炮的记录上还较清晰地显... 在大别造山带深地震测深剖面H维P波地壳速度结构的基础上,从地震记录的水平分量得到S波地壳速度结构,并用P波和S波的资料共同约束地壳的组成.剖面上大多数炮点的记录均显示了清晰的Sg和SmS震相.在埠塔寺炮和金拱炮的记录上还较清晰地显示出莫霍界面的反射转换震相PmS,表明在相应的范围内莫霍界面是一级间断面.在Pn和SmS震相都比较强的记录截面图上缺少相应的Sn震相,表示在上地幄顶部泊松比随深度急剧增大,在这一深度上物质可能存在局部熔融状态.剖面的地壳泊松比模型表明,上地壳在深度10km以内泊松比为025左右,仅北淮阳弧后复理石带较低,为0.23;扬子板块和华北板块的下地壳泊松比为0.26-0.27;在大别选山带,上地壳下部泊松比为0.22-0.24,而下地壳泊松比为0.27-0.30,其中超高压变质带最高.P、S波速度和泪松比表明超高压变质带下地壳主要由基性麻粒岩组成.大别造山带中、下地壳组成的横向不均匀性反映了在三叠纪造山作用期间扬子板块向华北板块俯冲,以及存在与地慢物质相联系的岩浆侵入体. 展开更多
关键词 造山带 超高压变质 s波速度结构 地震测深 地壳
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S-腺苷甲硫氨酸代谢途径相关基因在小麦水分胁迫中的表达 被引量:9
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作者 李昌澎 周琳璘 +4 位作者 陈亮 黄林周 陈晓杰 王宇珅 胡银岗 《西北植物学报》 CAS CSCD 北大核心 2011年第6期1120-1126,共7页
以小麦品种‘晋麦47’为材料,利用半定量RT-PCR方法,对S-腺苷甲硫氨酸代谢途径中的S-腺苷甲硫氨酸合成酶(SAMS)基因、S-腺苷甲硫氨酸脱羧酶(SAMDC)基因和γ-谷氨酰半胱氨酸合成酶(-γECS)基因在正常供水、PEG-6000模拟水分胁迫和... 以小麦品种‘晋麦47’为材料,利用半定量RT-PCR方法,对S-腺苷甲硫氨酸代谢途径中的S-腺苷甲硫氨酸合成酶(SAMS)基因、S-腺苷甲硫氨酸脱羧酶(SAMDC)基因和γ-谷氨酰半胱氨酸合成酶(-γECS)基因在正常供水、PEG-6000模拟水分胁迫和复水过程中小麦叶片的表达模式进行了分析。结果表明,3个基因在正常生长情况下有一定量的表达,SAMS和SAMDC基因在水分胁迫早期(PEG-6000胁迫6、12、244、8 h)上调表达,水分胁迫后期(PEG-6000胁迫75 h)表达量下降;复水后3~6 h上调表达,复水9 h后表达量下调至对照水平。-γECS基因在水分胁迫阶段呈上调表达,复水后表达量下调至对照水平。可见,小麦SAMS、SAMDC和-γECS基因的表达都受水分胁迫诱导,同时,SAMS与SAMDC基因还参与水分胁迫后的复水调节,说明S-腺苷甲硫氨酸代谢途径在小麦抗旱节水中具有重要作用。 展开更多
关键词 小麦 水分胁迫 s-腺苷甲硫氨酸代谢途径 表达模式 s-腺苷甲硫氨酸合成酶(sAMs) s-腺苷甲硫氨酸脱羧酶(sAMDC) γ-谷氨酰半胱氨酸合成酶(-γECs)
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渤海S油田窜流通道封堵技术 被引量:7
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作者 梁守成 吕鑫 +3 位作者 李强 陈冠中 李丽霞 温鸿滨 《油田化学》 CAS CSCD 北大核心 2017年第1期53-57,63,共6页
针对渤海S油田长期注水开发形成水窜通道,导致区块含水上升速度快的问题,采用示踪剂方法识别油水井间高渗条带,分析计算了高渗条带渗透率及孔喉大小,通过对凝胶类调剖体系强度和微球粒径分级、微球类调剖体系粒径与岩心孔喉直径的匹配... 针对渤海S油田长期注水开发形成水窜通道,导致区块含水上升速度快的问题,采用示踪剂方法识别油水井间高渗条带,分析计算了高渗条带渗透率及孔喉大小,通过对凝胶类调剖体系强度和微球粒径分级、微球类调剖体系粒径与岩心孔喉直径的匹配性和注入段塞及施工工艺组合方式的研究,获得了适合该油田高渗条带封堵及深部调剖的分级组合深部调剖技术。该技术的主要内容包括:以凝胶(先注弱凝胶,后注强凝胶)加微球为组合调剖剂,以凝胶井口调剖加微球在线调剖的组合工艺方式。研究结果表明,S油田目标井区高渗条带渗透率为8.8μm^2,平均孔喉约为20μm;适合分级组合深部调剖技术的两种强度凝胶体系配方为0.3%聚合物+0.2%交联剂(弱凝胶)、0.4%聚合物+0.3%交联剂(强凝胶);微球膨胀后的粒径与孔喉直径比为1~1.5时,微球调剖体系兼具良好的封堵性能和运移性能;应用凝胶封堵近井地带高渗条带、微球进行深部调剖的段塞组合方式,在相同成本下的调剖效果最好;采用井口调剖+在线调剖相结合的工艺方式,可使海上油田深部调剖设备占用平台空间降低70%以上。分级组合深部调剖技术在渤海S油田矿场试验中取得了显著效果,井组综合含水最高下降8.4%,井组净增油18288 m^3,适合于海上砂岩油田深部调剖作业。 展开更多
关键词 高渗条带 封堵 示踪剂 深部调剖 凝胶 微球 渤海s油田
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扶桑绵粉蚧谷胱甘肽S-转移酶基因的克隆及不同发育阶段的表达分析 被引量:3
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作者 罗梅 董章勇 +2 位作者 宾淑英 廖泓之 林进添 《西北农林科技大学学报(自然科学版)》 CSCD 北大核心 2012年第9期83-89,共7页
【目的】扶桑绵粉蚧是我国重要的入侵生物,其繁殖能力强,能危害棉花、扶桑、向日葵、南瓜、番茄等多种我国重要的经济作物。克隆扶桑绵粉蚧谷胱甘肽S-转移酶(GSTs)基因,可为揭示扶桑绵粉蚧GSTs的生理功能提供参考。【方法】利用RT-PCR和... 【目的】扶桑绵粉蚧是我国重要的入侵生物,其繁殖能力强,能危害棉花、扶桑、向日葵、南瓜、番茄等多种我国重要的经济作物。克隆扶桑绵粉蚧谷胱甘肽S-转移酶(GSTs)基因,可为揭示扶桑绵粉蚧GSTs的生理功能提供参考。【方法】利用RT-PCR和RACE技术克隆扶桑绵粉蚧谷胱甘肽S-转移酶基因全长,并采用生物信息学方法分析其结构特征,用实时荧光定量PCR的方法研究其各个虫态的表达谱。【结果】克隆了扶桑绵粉蚧谷胱甘肽S-转移酶基因全长序列,该基因的开放阅读框包含651bp的片段,编码217个氨基酸。DNA编码区由4个内含子和5个外显子组成,内含子的长度分别为90,123,67和70bp;分隔的5个外显子的长度分别为18,50,96,80和500bp。功能域分析结果显示,该蛋白在N末端和C末端均有GST的类似结构位点。多序列比对及系统进化树构建结果表明,该蛋白属Zeta家族GSTs,将其命名为PsGSTzl。PsGSTzl mRNA在扶桑绵粉蚧的不同虫态中都有表达,在1龄幼虫中的表达量最高。【结论】成功克隆的PsGSTzl基因在不同虫态中差异表达,为进一步揭示该基因在虫体的代谢作用奠定了基础。 展开更多
关键词 扶桑绵粉蚧 谷胱甘肽s-转移酶 克隆 表达谱
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基于R/S分析法的调剖注入压力动态变化特征量化评价 被引量:3
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作者 吴天江 杨海恩 +1 位作者 陈荣环 薛芳芳 《西安石油大学学报(自然科学版)》 CAS 北大核心 2016年第2期65-69,共5页
运用R/S分析法和分形理论计算调剖注入压力时间序列的Hurst指数及分形维数。对王窑长6油藏的6口井弱凝胶调剖注入压力曲线进行了实例计算。结果表明,调剖注入压力序列Hurst指数均大于0.5,平均值0.956 2,对应分形维数1.043 8。分段拟合... 运用R/S分析法和分形理论计算调剖注入压力时间序列的Hurst指数及分形维数。对王窑长6油藏的6口井弱凝胶调剖注入压力曲线进行了实例计算。结果表明,调剖注入压力序列Hurst指数均大于0.5,平均值0.956 2,对应分形维数1.043 8。分段拟合时第一阶段Hurst指数平均值0.718 3,中后期0.969 4,对应分形维数分别为1.281 7和1.030 6,调剖注入压力变化具有明显的阶段性,中后期注入压力上升的概率远高于初期,与分析堵剂在地层运移规律具有一致性。R/S分析法量化评价调剖注入压力是可行的。 展开更多
关键词 调剖注入压力 R/s分析法 HURsT指数 分形维
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