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Clinical significance of type V_I pit pattern subclassification in determining the depth of invasion of colorectal neoplasms 被引量:17
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作者 Hiroyuki Kanao Shinji Tanaka +5 位作者 Shiro Oka Iwao Kaneko Shigeto Yoshida Koji Arihiro Masaharu Yoshihara Kazuaki Chayama 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第2期211-217,共7页
AIM: To clarify whether subclassification of the type VI pit pattern on the basis of magnifying colonoscopy findings is useful in determining the type and depth of invasion of colorectal neoplasms.METHODS: We retrospe... AIM: To clarify whether subclassification of the type VI pit pattern on the basis of magnifying colonoscopy findings is useful in determining the type and depth of invasion of colorectal neoplasms.METHODS: We retrospectively analyzed 272 colorectal neoplasms (117 dysplasias and 155 submucosal invasive carcinomas; 228 patients) with a type V pit pattern [type VI, n = 202; type VN, n = 70 (Kudo and Tsuruta classification system)]. We divided lesions with a type VI pit pattern into two subclasses, mildly irregular lesions and severely irregular lesions, according to the prominent and detailed magnifying colonoscopy findings. We examined the relation between these two subclasses and histology/invasion depth.RESULTS: One hundred and four lesions (51.5%) were judged to be mildly irregular, and 98 lesions (48.5%) were judged to be severely irregular. Ninety-seven (93.3%) mildly irregular lesions showed dysplasias or submucosal invasion of less than 1000 μm (SM < 1000 μm). Fifty-five (56.1%) severely irregular lesions showed submucosal invasion equal to or deeper than 1000 μm (SM ≥ 1000 μm). Mild irregularity was found significantly more often in dysplasias or lesions with SM < 1000 μm than in lesions with SM ≥ 1000 μm (P < 0.01).CONCLUSION: Subclassification of the type VI pit pattern is useful for identifying dysplasias or lesions with SM < 1000 μm. 展开更多
关键词 Colorectal neoplasm MAGNIFICATION type VI pit pattern Depth of invasion
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Weathering,shock metamorphism and type distribution patterns of 98 ordinary chondrites from the Grove Mountains,Antarctica 被引量:1
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作者 戴德求 王道德 缪秉魁 《Chinese Journal of Polar Science》 2009年第2期215-224,共10页
Petrography and mineral chemistry of ninety-eight ordinary chondrites from Grove Mountains (GRV), Antarctica, were presented and their. Weathering effect, shock metamorphism and type distribution patterns were discu... Petrography and mineral chemistry of ninety-eight ordinary chondrites from Grove Mountains (GRV), Antarctica, were presented and their. Weathering effect, shock metamorphism and type distribution patterns were discussed in this study. Among them, six are unequilibrated ordinary chondrites, including 3 H3 and 3 L3 ; and 92 meteorites are equilibrated ordinary chondrites, including 24 H-group ( 13 H4, 10 H5, 1 H6), 64 L-group (2 L4, 44 L5, 18 L6) and 4 LL-group (3 LL4, 1 LL5). Most GRV ehondrites ( 〉 90% ) displayed minor weathering effect ( W1 and W2). About half of the meteorites experienced severe shock metamorphism. They commonly contain shock-induced melt veins and pockets. These heavily shocked meteorites provide us with natural samples for study of high-pressure polymorphs of minerals. In addition, the Grove Mountains collection seems to have more abundant unequilibrated and L group ordinary ehondrites compared to the US Antarctic meteorite collection which were mainly found along the Transantarctic Mountains. 展开更多
关键词 ordinary chondrites WEATHERING shock metamorphism type distribution patterns Antarctica.
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Structural patterns of land types and optimal allocation of land use in Qinling Mountains 被引量:12
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作者 LIU Yan-sui, DENG Xiang-zheng (Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China) 《Journal of Geographical Sciences》 SCIE CSCD 2001年第1期99-109,共11页
The case study based on Qinling Mountains in Shaanxi Province of China, in virtue of the information from TM image, classifies the land types and analyzes their spatial and temporal differential law, and puts forward ... The case study based on Qinling Mountains in Shaanxi Province of China, in virtue of the information from TM image, classifies the land types and analyzes their spatial and temporal differential law, and puts forward three structural patterns of land types in mountainous areas, namely, spatial, quantitative and qualitative structures of mountainous land types. Furthermore, it has been noticed that the analysis of structural patterns can disclose the heterogeneity and orderliness of combination of land types, which can lay the theoretic foundation for comprehensively recognizing ecological characteristics and succession law of structure and function of land types. After the all-around comparative analysis, an optimal allocation of land use in Qinling Mountains has been put forward according to the principle of sustainable development and landscape ecology, which can lay the scientific foundation in practice for the structural adjustment and distribution optimization from the macro level to micro level. 展开更多
关键词 land types succession of land types structural patterns optimal allocation Qinling Mountains
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The regional types of China's floating population: Identification methods and spatial patterns 被引量:9
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作者 LIU Shenghe HU Zhang +1 位作者 DENG Yu WANG Yingjie 《Journal of Geographical Sciences》 SCIE CSCD 2011年第1期35-48,共14页
With the rapid increase of the number and influence of floating population in China,it is urgently needed to understand the regional types of China's floating population and their spatial characteristics. After revie... With the rapid increase of the number and influence of floating population in China,it is urgently needed to understand the regional types of China's floating population and their spatial characteristics. After reviewing the current methods for identifying regional types of floating population,this paper puts forward a new composite-index identification method and its modification version which is consisted of two indexes of the net migration rate and gross migration rate. Then,the traditional single-index and the new composite-index identification methods are empirically tested to explore their spatial patterns and characteristics by using China's 2000 census data at county level. The results show:(1) The composite-index identification method is much better than traditional single-index method because it can measure the migration direction and scale of floating simultaneously,and in particular it can identify the unique regional types of floating population with large scale of immigration and emigration. (2) The modified composite-index identification method,by using the share of a region's certain type of floating population to the total in China as weights,can effectively correct the over-or under-estimated errors due to the rather large or small total population of a region. (3) The spatial patterns of different regional types of China's floating population are closely related to the regional differentiation of their natural environment,population density and socio-economic development level. The three active regional types of floating population are mainly located in the eastern part of China with lower elevation,more than 800 mm precipitation,rather higher population densities and economic development levels. 展开更多
关键词 China floating population regional types spatial pattern composite-index identification method
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Dietary Patterns and Their Association with Depression among Type 2 Diabetes Patients in Gaza Strip, Palestine 被引量:1
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作者 Abdel Hamid el Bilbeisi Mohammed Srour +2 位作者 Amany el Afifi Halgord Ali M. Farag Kurosh Djafarian 《Food and Nutrition Sciences》 2019年第5期533-550,共18页
Background: Depression is a common mental disorder. Globally, more than 340 million people of all ages suffer from depression. The aim of our study was to determine the association between major dietary patterns and d... Background: Depression is a common mental disorder. Globally, more than 340 million people of all ages suffer from depression. The aim of our study was to determine the association between major dietary patterns and depression among type 2 diabetes patients. Methods: This cross-sectional study was conducted among 480 type 2 diabetes patients attending primary healthcare centers in Gaza Strip, Palestine. The depression, anxiety, stress scales (DASS, 21-items) questionnaire was used to measure the score of depression. The participants’ demographic, socioeconomic and medical history data was collected and the 98-items semi-quantitative food frequency questionnaire was used for evaluating the dietary patterns. Statistical analysis was performed using SPSS version 20. Results: Based on depression scale, 29.0% of type 2 diabetes patients had depression, (58.3% females, and 41.7% males). The prevalence of mild, moderate, severe, and very severe depression was 11.7%, 8.5%, 6.7%, and 2.1%, respectively. Furthermore, two major dietary patterns were identified by factor analysis: The Western, and the grains-vegetables, and fruits patterns. After adjusting for the potential confounders, patients in the lowest tertile (T1) of the grains-vegetables, and fruits dietary pattern had a lower odds for depression (OR 0.763 95% CI (0.667 - 0.871), P value = 0.001);where as a higher odds for healthy (OR 1.443 95% CI (1.131 - 1.839), P value = 0.004), compared to those in the highest tertile (T3). Conclusion: The grains-vegetables, and fruits dietary pattern may be associated with a lower prevalence of depression, and has been shown to be the healthiest dietary pattern among type 2 diabetes patients. 展开更多
关键词 DEPRESSION DIETARY patterns Factor Analysis PREVALENCE type 2 DIABETES MELLITUS
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Identification of SNPs and expression patterns of FZD3 gene and its effect on wool traits in Chinese Merino sheep(Xinjiang Type) 被引量:4
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作者 ZHAO Bing-ru FU Xue-feng +9 位作者 TIAN Ke-chuan HUANG Xi-xia DI Jiang BAI Yan XU Xin-ming TIAN Yue-zhen WU Wei-wei ABLAT Sulayman ZENG Wei-dan HANIKEZI Tulafu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第10期2351-2360,共10页
As a member of the Frizzled family, Frizzled3 (FZD3) is a receptor of the canonical Wnt signaling pathway and plays a vital role in mammalian hair follicle developmental processes. However, its effects on wool traits ... As a member of the Frizzled family, Frizzled3 (FZD3) is a receptor of the canonical Wnt signaling pathway and plays a vital role in mammalian hair follicle developmental processes. However, its effects on wool traits are not clear. The objectives of this study were to identify the single nucleotide polymorphisms (SNPs) and the expression patterns of FZD3 gene, and then to determine whether it affected wool traits of Chinese Merino sheep (Xinjiang Type) or not. PCR-single stranded conformational polymorphism (PCR-SSCP) and sequencing were used to identify mutation loci, and general linear model (GLM) with SAS 9.1 was used for the association analysis between wool traits and SNPs. Quantitative real-time PCR (qRT-PCR) was used to investigate FZD3 gene expression levels. The results showed that six exons of FZD3 gene were amplified and two mutation loci were identified in exon 1 (NC_019459.2: g.101771685 T>C (SNP1)) and exon 3 (NC_019459.2: g.101810848, A>C (SNP2)), respectively. Association analysis showed that SNP1 was significantly associated with mean fiber diameter (MFD)(P=0.04) and live weight (LW)(P=0.0004), SNP2 was significantly associated with greasy fleece weight (GFW)(P=0.04). The expression level of FZD3 gene in skin tissues of the superfine wool (SF) group was significantly lower (P<0.05) than that of the fine wool (F) group. Moreover, it had a higher expression level (P<0.01) in skin tissues than in other tissues of Chinese Merino ewes. While, its expression level had a fluctuant expression in skin tissues at different developmental stages of embryos and born lambs, with the highest expression levels (P<0.01) at the 65th day of embryos. Our study revealed the genetic relationship between FZD3 variants and wool traits and two identified SNPs might serve as potential and valuable genetic markers for sheep breeding and lay a molecular genetic foundation for sheep marker-assisted selection (MAS). 展开更多
关键词 Chinese MERINO SHEEP (Xinjiang type) FZD3 single NUCLEOTIDE polymorphism (SNP) expression pattern association analysis WOOL TRAITS
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Stand development patterns of forest cover types in the natural forests of northern Baekdudaegan in South Korea
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作者 Ji Hong Kim Guangze Jin Sang Hoon Chung 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第2期381-390,共10页
The purpose of this study was to classify current forest cover types,and to investigate stand development patterns for natural forests in six areas in northern Baekdudaegan,South Korea.Twenty-eight independent forest ... The purpose of this study was to classify current forest cover types,and to investigate stand development patterns for natural forests in six areas in northern Baekdudaegan,South Korea.Twenty-eight independent forest communities were aggregated into eight forest cover types by species composition in the overstory of each forest community.The forest cover types were of mixed mesophytic,‘‘others’ ’ deciduous,Quercus mongolica dominant,Q.mongolica pure,Pinus densiflora–Q.mongolica,P.densiflora,Betula ermanii,and Q.mongolica–P.koraiensis.The ecological information was organized by importance value and species diversity for each forest type.Based on the correlation between species diversity index and the abundance of Q.mongolica plus P.densiflora for corresponding forest cover types,we compared the developmental process and approximate successional pathway between each cover type.The P.densiflora forest cover type changes into the P.densiflora–Q.mongolica cover type,followed by the Q.mongolica dominant cover type through continuous invasion of the oak trees.Furthermore,the Q.mongolica pure cover type would spread toward the Q.mongolica dominant cover type with a mixture of various deciduous tree species.The Q.mongolica dominant cover type progresses through the other deciduous cover types to the mixed mesophytic cover type with diversified composition and structure.On the mid to lower slopes,with loamy soils and good moisture conditions,various deciduous forest types should progress,by ecological succession,toward the mixed mesophytic cover type without any further disturbance. 展开更多
关键词 Baekdudaegan Forest cover type Species composition Species diversity Stand development patternS
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敦煌词格律的类型、特点及其本质
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作者 张培阳 《南阳师范学院学报》 2026年第2期33-40,共8页
敦煌词的出现,为中国古代词律乃至词律史的重新认识、塑造提供了一种重要的参照和变量,价值不可小视。以词调为视角,敦煌词的格律类型约可分为变化较小、变化较大和变化适中三类,三类乃至各类内部的格律风貌多不尽相同。敦煌词的格律特... 敦煌词的出现,为中国古代词律乃至词律史的重新认识、塑造提供了一种重要的参照和变量,价值不可小视。以词调为视角,敦煌词的格律类型约可分为变化较小、变化较大和变化适中三类,三类乃至各类内部的格律风貌多不尽相同。敦煌词的格律特点主要表现为两方面:一是词律变化较大的一种是三种类型中的主流;二是即使是词律变化较小的一种,其内部差异也往往甚于同调传世词。当然,以上特点并不意味着敦煌词的格律已毫无规则可言,而成为一种可以自由发挥的文体,否则,所谓敦煌词是否还能称为词,就大有可商了。 展开更多
关键词 敦煌词 格律 类型 特点 本质
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基于事件过程的珠江流域极端小时降水变化特征
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作者 宋晓猛 韦金江 张建云 《水科学进展》 北大核心 2026年第2期220-234,共15页
全球变暖背景下极端降水事件频发,对生态环境和人类社会构成严峻挑战,深入理解其变化特征对防洪减灾具有重要意义。本文利用多源数据融合的逐小时降水数据集,基于事件过程的极端小时降水(Event-based Extreme Hourly Precipitation,EEHP... 全球变暖背景下极端降水事件频发,对生态环境和人类社会构成严峻挑战,深入理解其变化特征对防洪减灾具有重要意义。本文利用多源数据融合的逐小时降水数据集,基于事件过程的极端小时降水(Event-based Extreme Hourly Precipitation,EEHP)分析框架,探讨珠江流域2000—2023年EEHP的时空变化特征,重点分析主导时间分布模式、历时-强度组合模式及其空间分布格局。结果表明:①EEHP总频次呈上升趋势,然而平均降水量和持续时间普遍呈下降趋势,年内高发期集中于5—6月,且日内降水主峰值多发于上午07:00—08:00和下午16:002个时段。②EEHP的各项指标具有相似的空间分布格局,总体为“西低东高”的分布特征。③前峰型时间分布模式为珠江流域EEHP的主导类型(占比87.4%),主要分布于流域西部的云贵-广西、东部的广东-福建及两广沿海地区,在春夏季最为活跃。④长历时-低强度EEHP是珠江流域事件占比最高的类型,低强度事件的空间分布呈“西北低、东南高”的格局,高强度事件的空间分布则相对均匀;不同组合类型的EEHP事件平均强度与平均历时呈现明显的逆向关系,平均历时随着平均强度增加而显著减小。 展开更多
关键词 极端小时降水 时间分布模式 季节性主导 历时-强度类型
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Utilization Pattern of Oral Hypoglycemic Agents for Diabetes Mellitus Type 2 Patients Attending Out-Patient Department at a University Hospital in New Delhi
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作者 Mohammad Shamshir Alam Mohammed Aqil +2 位作者 Syed Akmal Shah Qadry Prem Kapur Krishna K. Pillai 《Pharmacology & Pharmacy》 2014年第7期636-645,共10页
Diabetes mellitus is the chronic disorder emerging as major world health problem which increases the rate of morbidity and mortality. The aim of the present study was to ascertain patterns of prescription of oral hypo... Diabetes mellitus is the chronic disorder emerging as major world health problem which increases the rate of morbidity and mortality. The aim of the present study was to ascertain patterns of prescription of oral hypoglycemic agents to type 2 diabetic patients attending a university hospital, and to assess patient compliance. A prospective, observational and non comparative study was conducted in 200 established diabetes mellitus type 2 patients attending outpatient department at Majeedia Hospital, New Delhi, India. Prescriptions from registered patients were included in the study. Once the consultation by the physician was over, the prescriptions were reviewed and the patients were interviewed. The information was collected in an inhouse designed documentation proforma. In a pool of 200 type 2 diabetics, more than half were female (n=106, 53%). The mean age of the patients were found to be 50.4 ± 11.7 years and mean body mass index, 25.8 ± 4.4 kg/m2. A total of 432 oral hypoglycemic agents were prescribed to the patients. Highly significant number of patients were prescribed combination therapy, (n=143, 71.5%) as compared to monotherapy (n=57, 28.5%), 展开更多
关键词 Diabetes Mellitus type 2 Medicine Usage Evaluation Drug UTILIZATION PRESCRIBING pattern. Oral HYPOGLYCEMIC Agent
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蒙古国藏传佛教“向心性”殿堂建筑类型及成因探析
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作者 高旭 宋雨晨 王志强 《古建园林技术》 2026年第1期56-61,共6页
明清以降,在今蒙古国境域内藏传佛教的传播促使殿堂建筑大量涌现,“向心性”空间图式作为一种经典模式,得到广泛流布与衍化。本研究基于调研普查,对藏传佛教殿堂建筑的向心性类型进行划分,并从观念图式与建造逻辑两个维度解析不同类型... 明清以降,在今蒙古国境域内藏传佛教的传播促使殿堂建筑大量涌现,“向心性”空间图式作为一种经典模式,得到广泛流布与衍化。本研究基于调研普查,对藏传佛教殿堂建筑的向心性类型进行划分,并从观念图式与建造逻辑两个维度解析不同类型得以延续与发展的成因,揭示其内在演变机制,为该区域藏传佛教建筑的进一步研究奠定基础,以期对我国内蒙古地区藏传佛教建筑的演变发展提供参照对象与比较样本。 展开更多
关键词 向心性 空间图式 蒙古国 藏传佛教建筑 类型 成因
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基于GIS空间分析方法的九龙江河口土地利用研究
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作者 李丹丹 毕攀 +3 位作者 张媛静 李亚松 李剑锋 徐玉杰 《福建师范大学学报(自然科学版)》 北大核心 2026年第1期100-108,137,共10页
土地利用类型的时空分析研究可为一个地区的土地利用规划、水土保持及水资源保护提供重要价值。为研究九龙江河口地区土地利用类型变化,利用1990—2022年土地利用数据,采用土地利用转移矩阵、单一土地利用动态度、综合土地利用动态度、... 土地利用类型的时空分析研究可为一个地区的土地利用规划、水土保持及水资源保护提供重要价值。为研究九龙江河口地区土地利用类型变化,利用1990—2022年土地利用数据,采用土地利用转移矩阵、单一土地利用动态度、综合土地利用动态度、土地利用变化图谱等方法分析了九龙江河口地区土地利用类型时空变化和生态效应,并探讨了影响其变化的驱动力因素。结果表明:(1)研究区主要土地利用类型为农田、森林、水域和不透水面。农田是主要的土地利用类型,但是近30 a来面积逐渐减少,森林面积呈增减交替变化,水域面积先增后减,不透水面面积稳步增加;(2)土地利用类型转换形式丰富,农田多转化为森林、水域和不透水面,森林多转化为农田和不透水面,水域和不透水面多转化为农田;(3)土地利用变化造成的生态效应主要包括地面沉降、水质劣化、海水入侵和红树林固碳,养殖活动造成地面沉降和水质劣化,不透水面面积增加和加速沉降,红树林向河口上游生长趋势反映了对环境变化和生态系统的适应;(4)土地利用变化主要受经济、政策和人口因素驱动。研究结论可为研究区的水环境演变和水资源利用提供参考。 展开更多
关键词 九龙江河口 土地利用类型 时空格局 养殖 生态效应
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针对XML流数据的复杂Twig Pattern查询处理 被引量:9
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作者 杨卫东 王清明 施伯乐 《软件学报》 EI CSCD 北大核心 2007年第4期893-904,共12页
XML流数据处理在研究领域引起了研究者的广泛兴趣.针对XML流数据的、具有嵌套AND/OR谓词的复杂Twig Pattern查询处理,提出一种新方法.为了提高查询处理性能,将所有Twig Pattern合并为一个共享前缀的查询树,其中,AND/OR谓词被表示为单独... XML流数据处理在研究领域引起了研究者的广泛兴趣.针对XML流数据的、具有嵌套AND/OR谓词的复杂Twig Pattern查询处理,提出一种新方法.为了提高查询处理性能,将所有Twig Pattern合并为一个共享前缀的查询树,其中,AND/OR谓词被表示为单独的抽象语法树,因而能够以文档顺序、单遍地处理复杂Twig Pattern的匹配,并避免了YFilter中对嵌套谓词进行后置处理所产生的中间结果.实验结果表明,该方法能够有效改善Twig Pattern的处理性能,尤其是在处理大文档的情况下.基于已有的研究工作,讨论如何利用DTD(document type definition)的结构和约束信息优化Twig Pattern,即这种优化是在系统运行前进行的预处理. 展开更多
关键词 XML文档流 xPam TWIG pattern 查询树 DTD(document type definition)
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口语互动中连词引发的合作共建:类型、模式与功能
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作者 梁彩梅 姚双云 《新疆大学学报(哲学社会科学版)》 北大核心 2026年第1期176-188,共13页
合作共建是口语互动中普遍存在的现象,关乎会话进程,涉及词汇、短语、小句、复句等语言资源和身体视觉等多模态资源。目前关于合作共建的研究中,鲜有从话轮序列角度专门讨论连词引发的合作共建。本文基于300万字的汉语自然口语语料,分... 合作共建是口语互动中普遍存在的现象,关乎会话进程,涉及词汇、短语、小句、复句等语言资源和身体视觉等多模态资源。目前关于合作共建的研究中,鲜有从话轮序列角度专门讨论连词引发的合作共建。本文基于300万字的汉语自然口语语料,分析了由连词引发的合作共建的类型、典型的话语模式和基本的互动功能。根据连词在话轮序列中的不同位置分布,可将连词引发的合作共建分为居尾后联型、居首前接型、独立话轮型三种类型,从而构成四种典型的话语模式。合作共建中的连词主要有五种基本的互动功能:1)邀请完成;2)涉敏保留;3)引发抢夺;4)诱导信息;5)强化立场。 展开更多
关键词 连词 合作共建 类型 话语模式 互动功能
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大庆油田茂2区块扶余油层致密油井网井型优化及提高采收率潜力数值模拟
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作者 么忠文 唐维宇 《大庆石油地质与开发》 北大核心 2026年第2期97-104,共8页
大庆油田茂2区块扶余油层单层厚度薄、单井产能差异大、产能低,井型井网部署及后续提高采收率措施尚不明确。基于油藏数值模拟方法建立了核心区的油藏数值模拟模型并完成历史拟合,在此基础上分析了不同井网井型方案的开发特征,并评价了... 大庆油田茂2区块扶余油层单层厚度薄、单井产能差异大、产能低,井型井网部署及后续提高采收率措施尚不明确。基于油藏数值模拟方法建立了核心区的油藏数值模拟模型并完成历史拟合,在此基础上分析了不同井网井型方案的开发特征,并评价了不同提高采收率方法的增产潜力。结果表明:对于茂2区块致密油储层,水平井的单井产能远高于直井的单井产能,尽管产量递减较快,但相比直井井网,其净现值较高;满足经济效益的直井井网由于排距较大,注水或注气效果较差,生产井难以受效,而水平井井网采用CO_(2)吞吐的方式能够在前2个轮次经济有效地提高采收率。研究成果可为大庆油田扶余油层致密油藏进一步高效开发提供参考,在充分考虑布井方式、布井间距与CO_(2)吞吐时间的情况下,有望实现开发效益最大化。 展开更多
关键词 大庆油田 扶余油层 致密油 井网井型优化 提高采收率 数值模拟
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珠峰保护区陈塘沟兽类丰富度海拔与生境格局
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作者 章亚宁 胡一鸣 +6 位作者 黄志文 奚吉学 冯癸洋 杨乐 胡慧建 温知新 徐爱春 《生态学报》 北大核心 2026年第4期1881-1891,共11页
在全球高原生态系统持续受到气候变化与人类干扰影响的背景下,高海拔地区兽类多样性及其空间格局尚缺乏系统研究。作为南亚与青藏高原的重要生态过渡带,陈塘沟的物种组成、相对丰度及其沿海拔和生境梯度的变化规律仍不明确。旨在系统揭... 在全球高原生态系统持续受到气候变化与人类干扰影响的背景下,高海拔地区兽类多样性及其空间格局尚缺乏系统研究。作为南亚与青藏高原的重要生态过渡带,陈塘沟的物种组成、相对丰度及其沿海拔和生境梯度的变化规律仍不明确。旨在系统揭示该区域兽类多样性的空间格局,识别关键生境,并为高原生物多样性保护提供科学依据。研究于2023年7月至2024年11月在珠峰国家级自然保护区陈塘沟区域(46.14 km^(2))布设116台红外相机(间距≥500 m),覆盖不同海拔和生境类型,优先选择动物痕迹密集处,结合水源分布、植被状况及历史监测资料确定布设点位,共获取2515个相机工作日的数据,系统揭示了区域内兽类丰富度分布格局与生态功能结构。共记录19种兽类,其中食肉目物种数最多(12种),偶蹄目独立有效记录最多(510次),体现捕食者与草食动物的功能互补。共记录5种国家一级(喜马拉雅麝Moschus leucogaster、喜马拉雅斑羚Naemorhedus goral、雪豹Panthera uncia、金钱豹Panthera pardus和金猫Pardofelis temminckii)和10种国家二级保护野生动物(岩羊Pseudois nayaur、小熊猫Ailurus fulgens、猞猁Lynx lynx、云猫Pardofelis marmorata、豹猫Prionailurus bengalensis、熊猴Macaca assamensis、狼Vulpes vulpes、赤狐Martes flavigula、黄喉貂Canis lupus、石貂Martes foina),占调查兽类总种数的78%,凸显该区域在珍稀濒危物种保护中的枢纽地位。物种丰富度沿海拔梯度呈中峰格局,显示中低海拔生境在支持多样性方面的重要性。5种生境(阔叶林、针叶林、针阔混交林、灌丛和草甸)的兽类物种丰富度存在显著差异,其中草甸和灌丛的物种数最高。填补了该区域长期缺乏系统监测的空白,并可为高原生态保护提供科学依据,建议未来结合多源数据(如遥感、环境与人为干扰信息等)与功能多样性指标,从多维度揭示高原兽类群落的生态功能格局与环境响应机制,从而为区域生态保护与管理提供更科学的依据。 展开更多
关键词 红外相机监测 兽类 海拔梯度 物种丰富度格局 生境类型 珠穆朗玛峰国家级自然保护区
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围绝经期失眠患者中医体质类型及证型分布特征
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作者 张彦峰 郭蕾 +4 位作者 田育魁 孔静 摆雪 王程 刘俊昌 《中外女性健康研究》 2026年第2期1-5,共5页
目的:探讨围绝经期失眠(Perimenopausal Insomnia,PMI)患者的中医体质类型分布特征与中医证型、临床症状的关联性,为临床精准辨证施治提供依据。方法:依据王琦教授《中医体质分类研究》对36例PMI患者进行中医体质类型判定,参照《更年期... 目的:探讨围绝经期失眠(Perimenopausal Insomnia,PMI)患者的中医体质类型分布特征与中医证型、临床症状的关联性,为临床精准辨证施治提供依据。方法:依据王琦教授《中医体质分类研究》对36例PMI患者进行中医体质类型判定,参照《更年期综合征(围绝经期综合征)病证结合诊疗指南(2025)》判定中医证型;采用Spearman秩相关分析体质、证型与临床特征(既往生理特征、当前症状)的相关性。结果:1)体质分布:偏颇体质占88.89%,以阳虚质(10例)、气虚质(6例)与气郁质(5例)最为常见;2)证型分布:以肾系相关证型占主导,合计占69.45%,其中肾阴阳两虚证7/例,肾阳不足证、肾阴亏虚证、心肾不交证均为6例;3)相关性分析:①体质与症状:痰湿质与痛经正相关(r=0.402,P<0.05),气虚质与心悸(r=0.430,P<0.01)、头晕(r=0.408,P<0.01)正相关,气郁质与烦躁易怒(r=0.350,P<0.05)、抑郁焦虑(r=0.375,P<0.05)正相关,平和质与多项不良症状负相关;②体质与证型:气虚质与心脾两虚证/心肺气虚证相关性最强(r=0.6,P<0.001),阳虚质与肾阳不足证/肾阴阳两虚证相关(r=0.438,P<0.01),气郁质与肝气郁滞证相关(r=0.46,P<0.01)。结论:本研究中PMI患者的中医体质类型以阳虚质、气虚质多见,中医证型以肾系相关证型为主,PMI患者的中医体质类型与中医证型、临床症状存在显著关联性。 展开更多
关键词 围绝经期失眠 中医体质类型 中医证型 临床特征
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淮安市主城区热环境与热力景观格局时空演变特征分析
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作者 彭畅 陆东芳 《黑龙江生态工程职业学院学报》 2026年第2期77-83,共7页
以江苏省淮安市主城区为研究对象,基于2004—2024年Landsat系列遥感影像数据,反演地表温度并进行归一化处理,之后再采用均值标准差法将研究区划分为低温区、次低温区、中温区、次高温区和高温区五类热力景观类型。通过Fragstats软件计... 以江苏省淮安市主城区为研究对象,基于2004—2024年Landsat系列遥感影像数据,反演地表温度并进行归一化处理,之后再采用均值标准差法将研究区划分为低温区、次低温区、中温区、次高温区和高温区五类热力景观类型。通过Fragstats软件计算热力景观景观水平与类型水平分别对应的景观格局指数,系统分析近20年来淮安市主城区热环境的时空演变特征与热力景观格局变化趋势。结果表明:(1)热景观空间分布呈现显著空间分异,高温区主要集中于城市东北部建成区,而低温区多分布于西南部水域与耕地周边。(2)随着城市化进程加快,高温区范围2024年较2004年明显扩张并向外围蔓延,显示出城市扩张对热岛效应的驱动作用。(3)景观水平指数显示,热力景观破碎化程度整体上升(DIVISION上升),斑块趋于小型化与分散化,但聚集度(AI)略有增强,表明同类热景观斑块的空间聚合趋势加强。(4)类型水平分析揭示,中温区始终为优势景观类型,但其主导地位逐渐减弱;高温区斑块聚集度最高且持续上升,反映出城市建设用地热效应日益集中;而中温区斑块密度上升、平均面积下降,说明其完整性受到城市发展的持续侵蚀。 展开更多
关键词 城市热环境 热景观类型 热力景观格局 城市发展
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渤海湾盆地渤中凹陷西南部CO_(2)气成因及分布规律
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作者 胡安文 王飞龙 +2 位作者 彭靖淞 关超 刘梦醒 《中国海上油气》 北大核心 2026年第1期29-36,共8页
渤海湾盆地渤中凹陷西南部历经多年勘探,发现了多个大中型油气田,均含有一定丰度的CO_(2)气,但其成因、来源和分布缺乏研究。以渤中凹陷西南部渤中19-6和渤中21-22潜山CO_(2)气为研究对象,利用天然气组分、碳同位素、氦与氩同位素等资料... 渤海湾盆地渤中凹陷西南部历经多年勘探,发现了多个大中型油气田,均含有一定丰度的CO_(2)气,但其成因、来源和分布缺乏研究。以渤中凹陷西南部渤中19-6和渤中21-22潜山CO_(2)气为研究对象,利用天然气组分、碳同位素、氦与氩同位素等资料,开展CO_(2)气的成因与来源以及CO_(2)气的成藏主控因素及分布规律研究。结果表明:①渤中凹陷西南部CO_(2)气的相对含量分布范围广,主要为7.92%~51.02%,δ^(13)C_(CO_(2))值集中分布于-8.6‰~2.53‰,^(3)He/^(4)He、R/Ra及^(40)Ar/^(36)Ar值分别为2.62×10^(-6)~6.40×10^(-6)、1.87~4.57和273~463。②CO_(2)气以火山幔源无机成因为主,部分井区可能混有壳源无机气。渤中21-22潜山CO_(2)气主要分布在NE和EW向断裂交会处,渤中19-6潜山CO_(2)气与新生代玄武岩分布带一致,两潜山间CO_(2)气相对含量差异主要由烃类气混入产生的稀释作用所致。③不同级别断裂和岩浆活动是CO_(2)气生成、运聚和分布最重要的控制因素。渤中凹陷西南部发育2种CO_(2)成藏模式,分别为岩石圈断裂与交会的基底或盖层断裂将地幔脱气形成的CO_(2)直接运移至浅部聚集成藏型、地壳或基底断裂将壳内岩浆房中释放的CO_(2)运移至浅部聚集成藏型。研究成果可为CO_(2)聚集区预测和天然气勘探部署提供依据,降低勘探风险。 展开更多
关键词 CO_(2) 成因类型 分布规律 成藏模式 渤中凹陷 渤海湾盆地
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基于景观生态学原理的区域生态格局优化研究——以烟台市为例
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作者 赵高舒 乔楚晶 +2 位作者 宋江寒 王怀昱 高杨晓惠 《城市建筑》 2026年第2期23-26,共4页
构建城市生态安全格局对于维护国家和区域生态安全至关重要,是实现城市可持续发展的核心基础。这一过程既是保障生态安全的基本条件,也是推动城市持续进步的关键路径。本研究基于2000—2020年烟台市土地利用类型数据,运用ArcGIS和Fragst... 构建城市生态安全格局对于维护国家和区域生态安全至关重要,是实现城市可持续发展的核心基础。这一过程既是保障生态安全的基本条件,也是推动城市持续进步的关键路径。本研究基于2000—2020年烟台市土地利用类型数据,运用ArcGIS和Fragstats软件进行数据处理和运算,采用景观格局指数分析方法,通过对研究区各类景观要素面积变化、斑块属性、粒级结构及其动态变化过程进行分析,揭示烟台市多个时期景观格局的演变过程,阐明景观要素斑块规模的动态变化特点及其与景观格局指数的关联性。研究得出区域生态安全格局与土地利用格局间的内在联系,并针对其动态变化过程提出相应的生态格局优化策略,为滨海城市景观格局优化、生境保护与可持续发展提供一定的参考。 展开更多
关键词 景观生态格局 土地利用类型 斑块规模 景观指数
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