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先天性巨结肠患儿术后肠道组织中CAD、SOX2的表达水平及其临床意义
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作者 张宁 岳铭 袁宇航 《海南医学》 CAS 2024年第7期939-943,共5页
目的探讨先天性巨结肠(HD)患儿术后肠道组织蛋白酶D(CAD)、性别决定区Y框蛋白2(SOX2)的表达水平及其临床意义。方法选取2015年5月至2019年3月郑州大学第一附属医院收治的56例HD患儿结肠组织(HD组)和23例因肠道梗阻或穿孔实施造瘘手术获... 目的探讨先天性巨结肠(HD)患儿术后肠道组织蛋白酶D(CAD)、性别决定区Y框蛋白2(SOX2)的表达水平及其临床意义。方法选取2015年5月至2019年3月郑州大学第一附属医院收治的56例HD患儿结肠组织(HD组)和23例因肠道梗阻或穿孔实施造瘘手术获取的结肠组织标本(对照组)。采用免疫组化、Western-blot技术检测结肠组织中CAD、SOX2的表达水平,并采用Pearson线性相关分析法分析CAD、SOX2表达与病变肠段肌间神经丛直径、神经节细胞数的关系。结果HD患儿的狭窄段组织中CAD蛋白、SOX2蛋白阳性表达率分别为7.14%、12.50%,移行段肠组织中CAD蛋白、SOX2蛋白阳性表达率分别为32.14%、35.71%,明显低于对照组的78.26%、82.61%,而狭窄段组织中CAD蛋白、SOX2蛋白阳性表达率明显低于移行段,差异均有统计学意义(P<0.05);HD患儿的狭窄段肠组织中肌间神经丛直径、神经节细胞数目分别为(30.66±5.14)μm、(0.83±0.24)个/视野,移行段肠组织中肌间神经丛直径、神经节细胞数目分别为(31.20±5.83)μm、(1.94±0.56)个/视野,明显短(少)于对照组的(54.29±8.50)μm、(5.40±1.84)个/视野,狭窄段肠组织中肌间神经丛直径、神经节细胞数目明显短(少)于移行段,差异均有统计学意义(P<0.05);Pearson相关分析结果显示,HD患儿狭窄段、移行段肠组织中肌间神经丛直径、神经节细胞数目与CAD蛋白、SOX2蛋白表达强度均呈显著正相关(P<0.05)。结论HD患儿病变结肠组织中CAD蛋白、SOX2蛋白的表达强度下调,可能与肌间神经丛直径、神经节细胞数目的减少有关。 展开更多
关键词 先天性巨结肠 组织蛋白酶d 性别决定区Y框蛋白2 相关性
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Intraspecific Relationships and Variation of Two <i>Lefua</i>Species (Balitoridae, Cypriniformes) in the Tokai Region, Honshu, Japan 被引量:2
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作者 Jun-Ichi Miyazaki Seiya Hida +5 位作者 Takurou Ozaki Yuichirou Tabata Misaki Iwata Masashi Nakazawa Youki Fukasawa Tomonari Asaka 《Journal of Water Resource and Protection》 2017年第2期238-253,共16页
Two species Lefua echigonia and Lefua sp. 2 of the eight-barbel loach inhabit the Tokai region of Honshu, Japan. We determined sequences of the mitochondrial D-loop region to elucidate intraspecific phylogenetic relat... Two species Lefua echigonia and Lefua sp. 2 of the eight-barbel loach inhabit the Tokai region of Honshu, Japan. We determined sequences of the mitochondrial D-loop region to elucidate intraspecific phylogenetic relationships and variation in these two species. Lefua sp. 2 represented high intraspecific genetic similarity and complicated haplotype network, but three assemblages were recognized, including specimens mainly from Yahagi, Toyo, and Tenryu River systems, respectively, and named Groups 1 to 3. Divergence of Group 1 from the others was marginally supported, but Group 2 was paraphyletic to Group 3, suggesting the existence of two populations, i.e. Yahagi River population and Toyo-Tenryu River population. Lefua echigonia also represented high intraspecific genetic similarity, and two assemblages with slight genetic differentiation were discernible, including specimens from Shizuoka and southeastern Aichi prefectures and those from northwestern Aichi, Gifu, and Mie prefectures, respectively, and named Groups A and B. Star-like relationships of haplotypes suggested the dispersal origin located in eastern Aichi prefecture. The two species are threatened to extinction and thus we proposed evolutionary significant units for conservation. 展开更多
关键词 Population Phylogeography Mitochondrial d-Loop region Conservation River Capturing
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Hepatitis D: Scenario in the Asia-Pacifi c region 被引量:6
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作者 Zaigham Abbas Wasim Jafri Sajjad Raza 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第5期554-562,共9页
Hepatitis D virus (HDV) infection is present worldwide and affects all age groups. Around 18 million people are estimated to be infected with HDV. An important trend in HDV infection is global decline. HDV prevalence ... Hepatitis D virus (HDV) infection is present worldwide and affects all age groups. Around 18 million people are estimated to be infected with HDV. An important trend in HDV infection is global decline. HDV prevalence has decreased significantly in Europe since the 1970s and 1980s when it was f irst reported. The Asia-Pacif ic region now seems to be where HDV is a major health concern. There is a lack of available data from most of the countries from this region; hence, the true status of HDV cannot be determined. In South Asia, most of the countries have conditions that are favorable for the spread of hepatitis B and other related infections. Countries like Pakistan and Iran have shown an increase in HDV prevalence over a period of time. Other countries and region like China, Turkey, Australia, Japan, India and Taiwan, some of which had very high HDV prevalence in the past, have shown a decline in the incidence, but high prevalence persists in some. Intravenous drug abusers, homosexual men and women, prostitutes, and people on hemodialysis are the groups with very high HDV prevalence. 展开更多
关键词 Hepatitis d Asia-Pacif ic region PREVALENCE EPIdEMIOLOGY
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Deep seismic sounding investigation into the deep structure of the magma system in Changbaishan-Tianchi volcanic region 被引量:6
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作者 张先康 张成科 +7 位作者 赵金仁 杨卓欣 李松林 张建狮 刘宝峰 成双喜 孙国伟 潘素珍 《Acta Seismologica Sinica(English Edition)》 CSCD 2002年第2期143-151,共9页
The magma system of Changbaishan-Tianchi Volcanic region is studied with three-dimensional deep seismic sounding (DSS) technique. The results show that the magma system of Changbaishan-Tianchi volcanic region, mainly ... The magma system of Changbaishan-Tianchi Volcanic region is studied with three-dimensional deep seismic sounding (DSS) technique. The results show that the magma system of Changbaishan-Tianchi volcanic region, mainly characterized by low velocity of P wave, can be divided into three parts in terms of depth. At the depth range of 9-15 km, the distribution of the magma system is characterized by extensiveness, large scale and near-SN orientation. This layer is the major place for magma storage. From the depth of 15 km down to the lower crust, it is characterized by small lateral scale, which indicates the 'trace' of magma intrusion from the upper mantle into the crust and also implies that the magma system most probably extends to the upper mantle, or even deeper.(less than 8-9 km deep), the range of magma distribution is even smaller, centering on an SN-oriented area just north of the Tianchi crater. If low velocity of P wave is related to the magma system, it then reflects that the magma here is still in a state of relatively high temperature. In this sense, the magma system of Changbaishan-Tianchi volcanic region is at least not 'remains', in other words, it is in an 'active' state. 展开更多
关键词 Changbaishan-Tianchi volcanic region 3-d deep seismic sounding magma system
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Shear wave anisotropy in D” region beneath the western Pacific
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作者 戴志阳 刘斌 +3 位作者 王霄翔 查显杰 张虎 杨凤琴 《Acta Seismologica Sinica(English Edition)》 CSCD 2007年第5期489-496,共8页
Using seismic shear phases from 47 Tonga-Fiji and its adjacent region events recorded by the CENC and IRIS, and from 26 northeast Asia and north Pacific events recorded by IRIS, we studied the shear wave anisotropy i... Using seismic shear phases from 47 Tonga-Fiji and its adjacent region events recorded by the CENC and IRIS, and from 26 northeast Asia and north Pacific events recorded by IRIS, we studied the shear wave anisotropy in D" region beneath the western Pacific utilizing the ScS-S differential travel time method and obtained the splitting time values between the radial and transverse components of each ScS wave corresponding to each core-mantle boundary (CMB) reflection point. We found that most shear waves involved horizontally polarized shear wave components traveling faster than vertically polarized shear wave components through the D" region. The splitting time values of ScS wave range from -0.91 s to 3.21 s with an average value of 1.1 s. The strength of anisotropy varies from -0.45% to 1.56% with an average value of 0.52%. The observations and analyses show that in the D" region beneath the western Pacific the lateral flow is expected to be dominant and the vertical transverse isotropy may be the main anisotropic structure. This structure feature may be explained by the shape preferred orientation of the CMB chemical reaction products or partial melt and the lattice preferred orientation of the lower mantle materials caused by the lateral flow at lowermost mantle. 展开更多
关键词 ANISOTROPY shear wave splitting d region ScS phase the western Pacific
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庆阳驴mtDNA D-loop区遗传多样性及起源分析
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作者 施海娜 王永杰 +5 位作者 梁万鹏 耿智广 李世恩 徐振飞 刘刚 刘哲 《中国畜牧兽医》 CAS CSCD 北大核心 2024年第2期601-613,共13页
[目的]研究庆阳驴养殖群体的遗传多样性与母系起源,了解其遗传信息,为保护庆阳驴种质资源、选育和遗传改良工作提供理论依据。[方法]随机选取133头庆阳驴,对其线粒体DNA(mitochondrial DNA,mtDNA)D-loop区序列进行PCR扩增、测序及比对,... [目的]研究庆阳驴养殖群体的遗传多样性与母系起源,了解其遗传信息,为保护庆阳驴种质资源、选育和遗传改良工作提供理论依据。[方法]随机选取133头庆阳驴,对其线粒体DNA(mitochondrial DNA,mtDNA)D-loop区序列进行PCR扩增、测序及比对,并探讨庆阳驴的遗传多样性与母系起源。[结果]在获得的520 bp D-loop碱基序列中,AT含量(57.3%)高于GC含量(42.8%),表现出碱基的偏倚性;检测到38个变异位点,包含8个碱基对的转换;其核苷酸多样性(Pi)、单倍型多样性(Hd)、平均核苷酸差异(K)分别为0.01591、0.895和8.274,与欧洲家驴和中国家驴研究的平均值相比较低,说明该驴品种核苷酸变异较为贫乏。庆阳驴mtDNA D-loop区存在35个单倍型,单倍型之间的遗传距离为0.002~0.042。系统进化结果显示,庆阳驴存在2个线粒体支系,表明其具有2个母系起源,且遗传距离表明,庆阳驴与克罗地亚家驴之间的遗传距离较近。[结论]本研究从分子水平初步揭示庆阳驴核苷酸变异比较贫乏,杂交程度高,mtDNA遗传多态性正逐步丧失,应加强庆阳驴品种的遗传资源保护工作。 展开更多
关键词 庆阳驴 MTdNA d-LOOP区 遗传多样性 起源
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基于线粒体Cyt b基因和D-loop区分析元江鲤和杞麓鲤群体遗传结构
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作者 张铭枭 赵玉姣 +6 位作者 姚创 刘霄 黄松茂 李红涛 代忠礼 武祥伟 孔令富 《水产学杂志》 CAS 2024年第3期13-21,共9页
本文利用线粒体Cyt b基因和D-loop区部分序列,分析元江鲤(Cyprinus carpio yuankiang)和杞麓鲤(Cyprinus carpio chilia)群体的遗传结构。结果表明,在两个鲤群体中均获得929 bp的Cyt b基因序列和650 bp的D-Loop区序列。两个群体间平均... 本文利用线粒体Cyt b基因和D-loop区部分序列,分析元江鲤(Cyprinus carpio yuankiang)和杞麓鲤(Cyprinus carpio chilia)群体的遗传结构。结果表明,在两个鲤群体中均获得929 bp的Cyt b基因序列和650 bp的D-Loop区序列。两个群体间平均遗传距离为0.00595(Cyt b)、0.00852(D-loop)。Cyt b基因共检测出元江鲤3种、杞麓鲤15种单倍型,两个群体共享两个单倍型(C-Hap1和C-Hap3);D-loop区序列共检测出元江鲤3种、杞麓鲤6种单倍型,两个群体共享两个单倍型(D-Hap1和D-Hap2)。元江鲤和杞麓鲤群体单倍型多样性(Hd)分别为0.30±0.10(Cyt b)、0.25±0.10(D-loop)和0.89±0.04(Cyt b)、0.73±0.05(D-loop)。元江鲤和杞麓鲤群体核苷酸多样性(π)分别为0.12±0.04(Cyt b)、0.12±0.09(D-loop)和0.77±0.09(Cyt b)、0.87±0.07(D-loop),杞麓鲤遗传多样性水平明显高于元江鲤群体。分子方差分析(AMOVA)显示,两个群体间有明显的遗传分化,且遗传变异主要来源于群体间。系统发育分析显示,元江鲤群体单倍型较少,类型较单一,与杞麓鲤群体差异大,多数元江鲤样本单倍型属于华南鲤(Cyprinus carpio rubrofuscus)类型;多数杞麓鲤样本具特有单倍型,部分属于华南鲤、远东鲤(Cyprinus carpio haematopterus)类型。结果表明,杞麓鲤与元江鲤群体遗传分化明显,元江鲤线粒体遗传多样性较低。 展开更多
关键词 元江鲤 杞麓鲤 Cyt b基因 d-LOOP区 群体遗传结构 遗传多样性
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Complete Sequence Determination and Origin of Mitochondrial DNA Control Region in Dehua Black Chicken
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作者 Lu Junxian Jia Xiaoxu +4 位作者 Tang Xiujun Fan Yanfeng Gu Rong Ge Qinglian Gao Yushi 《Animal Husbandry and Feed Science》 CAS 2016年第5期261-263,共3页
Primers were designed according to the genomic DNA of red jungle fowl, and the complete sequence of mtDNA D-loop region in Dehua black chicken was obtained. Combined with the D-loop region complete sequence of red jun... Primers were designed according to the genomic DNA of red jungle fowl, and the complete sequence of mtDNA D-loop region in Dehua black chicken was obtained. Combined with the D-loop region complete sequence of red jungle fowl in GenBank, the maternal origin of Dehua black chicken was explored. The results showed that the complete sequence of mtDNA D-loop region in Dehua black chicken was 1 231 bp, and the average contents of T, C, A and G were 33.5%, 26.5%, 26.7% and 13.3%, respectively. Phylogenetic analysis showed that Dehua black chicken clustered with red jungle fowl ( C, allus gaUus spadiceus) , suggesting Dehua black chicken probably originated from G. g. spadiceu~ in Yunnan Province or nearby areas. 展开更多
关键词 dehua black chicken MTdNA d-loop region Phylogenetic relationship
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Assessing Post-Conflict Challenges and Opportunities of the Animal-Agriculture System in the Alpine Region of Uvira District in Sud-Kivu Province, D. R. Congo
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作者 M. M. D. Katunga J.-B. Muhigwa 《American Journal of Plant Sciences》 2014年第20期2948-2955,共8页
The Alpine region of Uvira District in South-Kivu Province faces low agricultural productivity challenges largely due to human population pressure on the natural resource base. During the dry season, conflicts between... The Alpine region of Uvira District in South-Kivu Province faces low agricultural productivity challenges largely due to human population pressure on the natural resource base. During the dry season, conflicts between crop farmers and livestock breeders are common. This region is located 2500 - 3020 m a.s.l. and is almost inaccessible due to poor road infrastructure. To understand the interactions between natural resources (forests, pastures, soils) and sedentary agriculture, and to propose solutions for sustainable natural resource management, Participatory Rural Appraisal (PRA) sessions covering three farmer group interviews were conducted in July 2010 in Marungu, Kitembe and Kahololo location. The livelihoods of the Banyamulenge have been transformed from pastoralism to a sedentary system with the introduction of crop cultivation after 1980. Maize, bush beans and Irish potatoes are cultivated with limited success because of late crop maturity under the prevailing climatic conditions. Livestock, mainly cattle, sheep and goats is managed under extensive system, relying on natural pasture far from the human settlements. Livestock plays an important role to define people’s wealth and is mainly managed by men. There is a real need of forages during the dry season;however, cultivation of forages is unknown. On the other hand, pastures appear to be degenerating due to overgrazing. Access by farmers to efficient and effective agricultural extension services is fundamental in order to promote locally adapted and profitable crop and livestock production while at the same time, sustaining the productive resource base and security. 展开更多
关键词 LIVESTOCK Agriculture ALPINE region d. R. CONGO
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Primary Analysis on mtDNA D-loop Hypervariable Region in Eutamias sibiricus
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作者 LI Shipeng BAI Xiujuan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2008年第1期48-50,共3页
This study analyzed the mitochondrial DNA D-loop hypervariable region 601 bp sequence in 12 Eutamias sibiricus from Heilongjiang area. The result showed that the average contents of A, T, G and C were 33.2%, 30.5%, 11... This study analyzed the mitochondrial DNA D-loop hypervariable region 601 bp sequence in 12 Eutamias sibiricus from Heilongjiang area. The result showed that the average contents of A, T, G and C were 33.2%, 30.5%, 11.8% and 24.5% respectively, the A+T content (63.7%) was obviously higher than the G+C content (36.3%). Thirty-six, mutation (approximately 6.0%) sites were found and 9 haplotypes were defined. The mutations types, including transition, transversion and deletion were all found in the detected mtDNA D-loop regions, most of which was transition. The average nucleotide mutational ratio was 1.22%. The nucleotide mutation sites affected the restriction site appearance or disappearance of the restriction site. The research on mtDNA D-loop is focused on the domestic animals and there is no report on Eutamias sibiricus, This study analyzed the mitochondrial DNA D-loop hypervariable in Eutamias sibiricus so as to provide some useful informations for related research in the future. 展开更多
关键词 Eutamias sibiricus mtdNA d-loop hypervariable region genetic diversity
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A study on 3-D velocity structure of crust and upper mantle in Sichuan -Yunnan region, China 被引量:6
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作者 王椿镛 Mooney W.D +3 位作者 王溪莉 吴建平 楼海 王飞 《Acta Seismologica Sinica(English Edition)》 CSCD 2002年第1期1-17,共17页
Based on the first arrival P and S data of 4 625 regional earthquakes recorded at 174 stations dispersed in the Yunnan and Sichuan Provinces, the 3-D velocity structure of crust and upper mantle in the region is deter... Based on the first arrival P and S data of 4 625 regional earthquakes recorded at 174 stations dispersed in the Yunnan and Sichuan Provinces, the 3-D velocity structure of crust and upper mantle in the region is determined, incorporating with previous deep geophysical data. In the upper crust, a positive anomaly velocity zone exists in the Sichuan basin, whereas a negative anomaly velocity zone exists in the western Sichuan plateau. The boundary between the positive and negative anomaly zones is the Longmenshan fault zone. The images of lower crust and upper mantle in the Longmenshan fault, Xianshuihe fault, Honghe fault and others show the characteristic of tectonic boundary, indicating that the faults likely penetrate the Moho discontinuity. The negative velocity anomalies at the depth of 50 km in the Tengchong volcanic area and the Panxi tectonic zone appear to be associated with the temperature and composition variations in the upper mantle. The overall features of the crustal and the upper mantle structures in the SichuanYunnan region are the lower average velocity in both crust and uppermost mantle, the large crustal thickness variations, and the existence of high conductivity layer in the crust or/and upper mantle, and higher geothermal value. All these features are closely related to the collision between the India and the Asia plates. The crustal velocity in the SichuanYunnan rhombic block generally shows normal value or positive anomaly, while the negative anomaly exists in the area along the large strike-slip faults as the block boundary. It is conducive to the crustal block side-pressing out along the faults. In the major seismic zones, the seismicity is relative to the negative anomaly velocity. Most strong earthquakes occurred in the upper-mid crust with positive anomaly or normal velocity, where the negative anomaly zone generally exists below. 展开更多
关键词 regional earthquake Moho discontinuity 3-d velocity structure network method plate collision SEISMICITY
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Two-step interface and velocity inversion—— Study o e of the Tangshan seismic region
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作者 XIAO LING LAI XIAN KANG ZHANG XU YAO ZHENG Research Center of Exploration Geophysics, China Seismological Bureau, Zhengzhou 450003, China 《Acta Seismologica Sinica(English Edition)》 CSCD 1998年第6期34-44,共11页
This paper studies the computation method of two step inversion of interface and velocity in a region. The 3 D interface is described by a segmented incomplete polynomial; while the reconstruction of 3 D velocity i... This paper studies the computation method of two step inversion of interface and velocity in a region. The 3 D interface is described by a segmented incomplete polynomial; while the reconstruction of 3 D velocity is accomplished by the principle of least squares in functional space. The computation is carried out in two steps. The first step is to inverse the shape of 3 D interface; while the second step is to do 3 D velocity inversion by distributing the remaining residual errors of travel time in accordance with their weights. The data of seismic sounding in the Tangshan Luanxian seismic region are processed, from which the 3 D structural form in depth of the Tangshan seismic region and the 3 D velocity distribution in the crust below the Tangshan Luanxian seismic region are obtained. The result shows that the deep 3 D structure in the Tangshan seismic region trends NE on the whole and the structure sandwiched between the NE trending Fengtai Yejituo fault and the NE trending Tangshan fault is an uplifted zone of the Moho. In the 3 D velocity structure of middle lower crust below that region, there is an obvious belt of low velocity anomaly to exist along the NE trending Tangshan fault, the position of which tallies with that of the Tangshan seismicity belt. The larger block of low velocity anomaly near Shaheyi corresponds to a denser earthquake distribution. In that region, there is an NW trending belt of high velocity anomaly, probably a buried fault zone. The lower crust below the epicentral region of the Tangshan M S=7.8 earthquake is a place where the NE trending belt of low velocity anomaly meets the NW trending belt of high velocity anomaly. The two sets of structures had played an important role in controlling the preparation and occurrence of the M S=7.8 Tangshan earthquake. 展开更多
关键词 two step interface and velocity inversion 3 d velocity pattern of crust below Tangshan seismic region seismicity zone
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Numerical simulation of characteristics of semidiurnal tidal waves in sea region around Taiwan 被引量:5
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作者 Sha Wenyu, Lu Xingang, Chen Xi, Zhang Wenjing 1. Cullege of Meterology. Institute of Science and Engineering of the P. L. A. Nanjing 211101, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2001年第3期317-330,共14页
POM97, an oceanic model, has been used for the first time to the numerical study on the tidal waves of the as Regions around Taiwan. In this paper, we have got the result that the semidiurnal tidal waves of these area... POM97, an oceanic model, has been used for the first time to the numerical study on the tidal waves of the as Regions around Taiwan. In this paper, we have got the result that the semidiurnal tidal waves of these area mainly are the co-operating tides which come from the south of 23'N of the western Pacific. Those semidiurnal tidal waves affecting the Taiwan Straits come respectively from the south and the north entrance of the channel, and the north tidal wave is stronger than the south one. The strongest tidal field is the area from the Meizhou Bay to the Xinhua Bay along the coast of Fujian Province, where the biggest amplitude of the M2 partial tide can reach 240 cm. The strongest tidal cur- rent fields lie in the Penghu watercourse, where the maximum velocity of the M2 partial tide can arrive at 196 m/s. In the horizontal structure of the tidal currets, we have found that there is a stream dot in the north of the channel, besides, there still exist four new ones. As for the vertical structure, it mainly is biassed to the right at the surface, and to the left near the bottom layer. 展开更多
关键词 Sea regions around Taiwan semidiurnal tidal waves 3 - d numerical simulation
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伴中央颞区棘波的儿童自限性癫痫发作与血浆氨及25羟维生素D水平相关性研究
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作者 徐婷 王秋影 +3 位作者 刘时华 张超 钟平 曹立 《中国现代医生》 2024年第17期62-65,75,共5页
目的探讨伴中央颞区棘波的儿童自限性癫痫(self-limited epilepsy in children with spines in the central temporal region,SeLECTS)发作与血浆氨及25羟维生素D[25-hydroxyvitamin D,25(OH)D]水平相关性。方法选取2021年9月至2023年1... 目的探讨伴中央颞区棘波的儿童自限性癫痫(self-limited epilepsy in children with spines in the central temporal region,SeLECTS)发作与血浆氨及25羟维生素D[25-hydroxyvitamin D,25(OH)D]水平相关性。方法选取2021年9月至2023年10月安徽医科大学附属宿州医院收治的90例SeLECTS患儿为病例组,同期90例宿州地区健康体检儿童为对照组,比较两组研究对象的血浆氨及血清25(OH)D水平差异,回顾分析SeLECTS临床特点与血浆氨及25(OH)D水平的相关性。结果病例组患儿的血浆氨浓度高于对照组(P<0.05),25(OH)D水平明显低于对照组(P<0.05)。不同发病年龄、发作时间、发作频率的SeLECTS患儿,血浆氨浓度差异有统计学意义(P<0.05);不同发病年龄、发作频率、发作季节的SeLECTS患儿,血清25(OH)D含量差异有统计学意义(P<0.05)。发作时间与发病年龄、发病频率之间的相关性差异有统计学意义(P<0.01);而血浆氨浓度与发病年龄、发作时间、发作频率之间的相关性差异有统计学意义(P<0.05);同时25(OH)D含量与发作时间、发作频率、血浆氨浓度之间相关性差异有统计学意义(P<0.05)。SeLECTS患儿发病年龄、发作频率、发作时间与血浆氨水平呈正相关;发病年龄与25(OH)D水平呈正相关,发作频率与25(OH)D水平呈负相关。结论SeLECTS发作与血浆氨及血清25(OH)D水平之间存在相关性,血浆氨水平升高或25(OH)D水平降低皆会增加SeLECTS发作的风险。因此,通过检验患儿血浆氨及血清25(OH)D含量可为预防、病情评估及诊治SeLECTS提供依据。 展开更多
关键词 伴中央颞区棘波的儿童自限性癫痫 血浆氨 25-羟维生素d
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Crustal and uppermost mantle structure of Caucasus and surrounding regions
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作者 Youshun Sun M Nafi Toksz +4 位作者 Randolph J Martin Mary Krasovec Diming Yu Qingyun Liu Jun Liu 《Earthquake Science》 CSCD 2012年第5期505-515,共11页
A 3-D P-wave velocity model is developed for the crust and uppermost mantle of Caucasus and the surrounding area by applying the tomographic method of Zhao et al. using 300 000 high-quality P-wave first arrivals from ... A 3-D P-wave velocity model is developed for the crust and uppermost mantle of Caucasus and the surrounding area by applying the tomographic method of Zhao et al. using 300 000 high-quality P-wave first arrivals from 43 000 events between 1964 and 2005. This tomographic method can accommodate velocity discontinuities such as the Moho in addition to smooth velocity variations. The spatial resolution is 1°× 1° in the horizontal direction and 10 km in depth. The velocity images of the upper crust correspond well with the surface geology. Beneath the southern Caucasus high velocity anomalies are found in the middle crust and low velocity anomalies are found in the uppermost mantle. Relatively low Pn velocities are located under the Lesser Caucasus, eastern Turkey, and northern Iran. Higher Pn velocities occur under the eastern portion of the Black Sea and the southern Caspian Sea, and also extend into the eastern edge of Azerbaijan. Tomographic model significantly reduces the travel-time residuals. 展开更多
关键词 Caucasus region crustal structure Pn velocity 3-d tomography
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Regional pole assignment for uncertain delta-operator systems
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作者 ManLIU YuanweiJING SiyingZHANG 《控制理论与应用(英文版)》 EI 2004年第4期406-410,共5页
The pole assignment in a specified disk by state feedback for uncertain delta-operator systems is studied. By making use of algebra Riccati equations, a sufficient and necessary condition of pole assignment for a kind... The pole assignment in a specified disk by state feedback for uncertain delta-operator systems is studied. By making use of algebra Riccati equations, a sufficient and necessary condition of pole assignment for a kind of parameter uncertain delta-operator system in a specified disk by state feedback is presented. And the design method of state feedback controller is also developed. The proposed method can unify some previous related results of continuous and discrete time systems into the delta framework. The efficiency of the design method is illustrated by a numerical example. 展开更多
关键词 delta-operator system regional pole assignment UNCERTAINTY ROBUSTNESS Quadratic d stabilizability
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长三角D-2日电能量市场机制设计
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作者 胡朝阳 杜非 +2 位作者 段翩 张丙金 陈雨果 《电力自动化设备》 EI CSCD 北大核心 2024年第4期197-203,共7页
立足于我国多层次市场体系建设现状和国、网、省三级调度业务架构,界定现阶段区域内省间市场和跨区省间市场在全国统一电力市场中的功能定位。为了解决不同范围、不同周期市场的衔接问题,提出建设长三角D-2日电能量市场,通过D-2日电能... 立足于我国多层次市场体系建设现状和国、网、省三级调度业务架构,界定现阶段区域内省间市场和跨区省间市场在全国统一电力市场中的功能定位。为了解决不同范围、不同周期市场的衔接问题,提出建设长三角D-2日电能量市场,通过D-2日电能量市场统筹全网电力电量平衡,保障区外送电计划的可执行性,实现市场从中长期到日前的平滑过渡。引入市场用户报量报价参与区域市场;设计市场衔接、市场定价、偏差处理等关键机制;考虑到华东电网是耦合关系复杂的交流电网,构建全网络出清模型。算例结果表明,D-2日电能量市场有利于全网资源优化配置,保障全网电力安全以及解决发电侧市场力问题,证明了市场机制设计的有效性。 展开更多
关键词 区域电力市场 市场衔接 d-2日电能量市场 跨省交易定价机制 市场出清模型
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鲤属鱼类mtDNA控制区(D-环区)序列的变异性分析 被引量:27
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作者 郑冰蓉 张亚平 +2 位作者 肖蘅 蓝家湖 昝瑞光 《水产学报》 CAS CSCD 北大核心 2002年第4期289-294,共6页
采用PCR-测序技术对我国鲤属7个种、亚种和2个品种共62个个体(其中鲤的样品包括采自长江、黄河、松花江三个水系的共4个种群),进行了mtDNA控制区(D-环区)始自3’端共459bp碱基的序列测定,发现其D-环区3’端至中央保守区之间不似其他鱼... 采用PCR-测序技术对我国鲤属7个种、亚种和2个品种共62个个体(其中鲤的样品包括采自长江、黄河、松花江三个水系的共4个种群),进行了mtDNA控制区(D-环区)始自3’端共459bp碱基的序列测定,发现其D-环区3’端至中央保守区之间不似其他鱼类和哺乳类是一个单一的高变区,而是在其内部还插有一段长约110bp的保守区,这很可能是鲤属鱼类mtDNA D-环区自身的一个特点。 展开更多
关键词 鲤属 鱼类 MTdNA控制区 d-环区 变异性 线粒体 序列分析
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我国部分黄牛品种线粒体D-loop区遗传多样性与起源分化 被引量:19
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作者 张桂香 郑友民 +3 位作者 王志刚 韩旭 贾善刚 陈宏 《遗传》 CAS CSCD 北大核心 2009年第2期160-168,共9页
为了解我国地方黄牛品种线粒体DNA的遗传变异情况,文章测定了16个地方黄牛品种206个个体线粒体D-loop区的全序列,共检测到101个变异位点;99种单倍型,其中73种是普通牛单倍型,26种是瘤牛单倍型;平均核苷酸差异为22.6920,单倍型多样度为0.... 为了解我国地方黄牛品种线粒体DNA的遗传变异情况,文章测定了16个地方黄牛品种206个个体线粒体D-loop区的全序列,共检测到101个变异位点;99种单倍型,其中73种是普通牛单倍型,26种是瘤牛单倍型;平均核苷酸差异为22.6920,单倍型多样度为0.9320,核苷酸多样度为0.0227,表明我国黄牛品种遗传多样性非常丰富。构建的NJ进化树显示16个品种来源于两大母系:普通牛和瘤牛;构建的Network图表明73种普通牛单倍型可以分为3大单倍型群;26种瘤牛单倍型分为5种单倍型群,推测我国瘤牛在迁移过程中,至少经历了4次群体扩张事件。通过分析比较地方黄牛品种与内罗门牛共有的H3单倍型,发现其中只有16%的序列与内罗门牛的H3单倍型非常相似,其余84%的序列均发生了鸟嘌呤变异,推测这些变异很可能是我国瘤牛固有的变异。 展开更多
关键词 黄牛 d-LOOP区 遗传多样性 起源 分化
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基于MF雷达观测的D区日食效应的研究 被引量:7
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作者 李娜 陈金松 +1 位作者 赵蕾 赵振维 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2011年第4期942-949,共8页
本文利用昆明站(25.6°N,103.8°E)MF雷达在2009年7月22日的观测数据,研究了这次日食期间D区电子密度的变化.结果表明,随着日食的开始,D区电子密度逐渐减小,在食甚后,电子密度开始恢复.但观测发现电子密度不与日食同步,而是存... 本文利用昆明站(25.6°N,103.8°E)MF雷达在2009年7月22日的观测数据,研究了这次日食期间D区电子密度的变化.结果表明,随着日食的开始,D区电子密度逐渐减小,在食甚后,电子密度开始恢复.但观测发现电子密度不与日食同步,而是存在一个大约9 min的时延.利用日食期间的观测数据,尝试建立了两个简单的模型来估算D区的有效复合系数,模型结果与以往的理论研究和观测保持了较好的一致性,其中模型二较模型一更适合于D区有效复合系数的计算. 展开更多
关键词 MF雷达 日食 电子密度 有效复合系数 d
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