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Haplotype and Genetic Analysis of 41 Y-STR Loci in the Wuwei Han Population from Gansu Province,China
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作者 Lu-yao LI Sheng-gui FAN +4 位作者 Hui GONG Xing FAN De-chun WANG Neng-xiu LI Fu-quan JIA 《Current Medical Science》 SCIE CAS 2023年第1期184-190,共7页
Objective Y-Chromosomal short tandem repeat polymorphism(Y-STR)analysis plays an indispensable role in the identification of male individuals,population genetics,and biogeographic research.While profiles of many popul... Objective Y-Chromosomal short tandem repeat polymorphism(Y-STR)analysis plays an indispensable role in the identification of male individuals,population genetics,and biogeographic research.While profiles of many populations based on Y-STR markers in human genomes are ample,haplotype data for the Wuwei Han are still scarce.Methods In this study,2180 unrelated Wuwei Han male individuals residing in Gansu Province,China were collected and genotyped using the novel Microreader™40Y Plus ID system.Phylogenetic relationship reconstructions,multidimensional scaling(MDS),and heatmap analysis were performed based on the genetic distance(Rst)values between our studied population and other populations of the Ymax module in the Y-STR Haplotype Reference Database(YHRD).Results A total of 2129 unique haplotypes were obtained,and the haplotype diversity(HD)and discrimination capacity(DC)for the Wuwei Han were 0.9999 and 0.9931,respectively.Conclusion Our results demonstrate that the Wuwei Han population had intimate genetic relationships with East Asians,especially the geographically close Han populations.Overall,this Y-Chromosomal assay gives valuable information about paternal lineages in male individual tracking and genealogical database construction. 展开更多
关键词 MicroreaderTM 40Y Plus ID system Y-STR haplotype Y-InDel wuwei Han population genetics
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ENVIRONMENTAL SUSTAINABILITY AND SCENARIOS OF URBANIZATION IN ARID AREA——A Case Study in Wuwei City of Gansu Province 被引量:4
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作者 YOUFei LIYu DONGSuo-cheng 《Chinese Geographical Science》 SCIE CSCD 2005年第2期120-130,共11页
Based on data of questionnaire and field survey and two developing models of Business As Usual (BAU) and the Intensive Urbanization (IU), this article, taking Wuwei City, a medium size city and typical oasis arid area... Based on data of questionnaire and field survey and two developing models of Business As Usual (BAU) and the Intensive Urbanization (IU), this article, taking Wuwei City, a medium size city and typical oasis arid area in Gansu Province with very vulnerable and sensitive natural environment but long history of oasis economy, as an example, evaluated the sustainability of its environment and analyzed the scenarios of Wuwei’s household energy consumption, waste discharge in transportation industry, primary industry, secondary industry, tertiary industry, by the integration of the systematical dynamics model Stella and Polestar language to simulate the future development of the research area. The results showed that, first, the developing model of IU was propitious to Wuwei City named for oasis economy and vulnerable natural environment. The strategy of "Intensive Urbanization" can change the structure of energy utilization, and improve the efficiency of energy utilization. Second, the proportion of domestic energy consumption will decrease with industrialization and economic development, while that of tertiary industry, secondary industry and transportation will gradually grow up according to strategy of "Intensive Urbanization". Third, the Wuwei City is facing a severe eco-environmental crisis under the conventional patterns of development and a better future under a sustainable urbanization scenario, in the next 10 to 20 years. The different developing trends were clarified and the relative countermeasures were put forward for the policy makers according to the driving forces. 展开更多
关键词 城市化发展 环境破坏 生态经济承受性 中国西部
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The amplification effect of PGA and the large-scale liquefaction-triggered mudflow during the December 18,2023 M 6.2 Jishishan Earthquake in Gansu Province,China
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作者 Lanmin Wang Shiyang Xu 《Earthquake Research Advances》 CSCD 2024年第2期11-13,共3页
At 23:59 on December 18, 2023, a strong earthquake (M 6.2) struck Jishishan County in Gansu province, China, which is situated in the transition zone between Qinghai-Xizang Plateau and the Loess Plateau.The focal dept... At 23:59 on December 18, 2023, a strong earthquake (M 6.2) struck Jishishan County in Gansu province, China, which is situated in the transition zone between Qinghai-Xizang Plateau and the Loess Plateau.The focal depth is 10 km, and the epicenter (35.70°N and 102.79°E) is about 100 km southwest away from Lanzhou, the capital city of Gansu province. As of December 31, 2023, the earthquake has caused 151 people dead and 979 people wounded in Gansu and Qinghai. 展开更多
关键词 gansu SOUTHWEST situated
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Effects of Wuwei Xiaodu Decoction on Uterine Energy Metabolism and Serum Inflammatory Factors in Rats with Acute Pelvic Inflammatory Disease
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作者 Hongying WU Kai DING 《Medicinal Plant》 2024年第2期38-39,共2页
[Objectives]To observe the effects of Wuwei Xiaodu Decoction on uterine energy metabolism and serum inflammatory factors in the acute pelvic inflammatory disease(APID)model.[Methods]75 Wistar rats(females)were randoml... [Objectives]To observe the effects of Wuwei Xiaodu Decoction on uterine energy metabolism and serum inflammatory factors in the acute pelvic inflammatory disease(APID)model.[Methods]75 Wistar rats(females)were randomly divided into control group,model group and Wuwei Xiaodu Decoction low,medium and high dose groups(n=15).Except for the control group,the rat APID model was established by right uterine inoculation.On the fifth day after inoculation,the low,medium and high dose groups of Wuwei Xiaodu Decoction were administered at 4,8 and 16 g/kg,and the control group and model group received normal saline.Rats were killed 12 h after nondose administration,blood was collected from the abdominal aorta and measured by ELISA for serum interleukin-6(interleukin-6,IL-6),IL-8,and C-reactive proteins(CRP);the right uterus of rats was tested for high-energy phosphate adenosine phosphate(AMP),adenosine diphosphate(ADP),adenosine triphosphate(ATP)and total adenine nucleotides(TAN)level to evaluate the uterine energy metabolism.[Results]AMP,ADP,ATP and TAN were significantly higher in the Wuwei Xiaodu Decoction of low,medium and high dose than the model group,while the serum IL-6,IL-8 and CRP were significantly lower than the model group,and the difference between the low,medium and high doses(P<0.05).[Conclusions]The Wuwei Xiaodu Decoction can dose-dependent promote uterine energy metabolism and inhibit inflammatory response in APID model rats. 展开更多
关键词 wuwei Xiaodu Decoction Acute pelvic inflammatory disease Uterine energy metabolism Inflammatory factors
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Preparation Technology of Wuwei Xiaoke Granules
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作者 Shengbin CHEN Guangyuan XIE +4 位作者 Yulong WEI Yanqiong HUANG Xuanyang ZENG Xiaomin DENG Mingzheng HUANG 《Medicinal Plant》 2023年第6期31-34,共4页
[Objectives]To optimize the extraction and preparation technology of Wuwei Xiaoke granules.[Methods]Taking the extraction rate of extract as the scoring standard,the water extraction technology was optimized by orthog... [Objectives]To optimize the extraction and preparation technology of Wuwei Xiaoke granules.[Methods]Taking the extraction rate of extract as the scoring standard,the water extraction technology was optimized by orthogonal test.The influence of the proportion of pharmaceutical excipients on the molding conditions of Wuwei Xiaoke granules was investigated using granule molding rate,solubility,moisture,granularity,water-soluble extract and microorganism examination as evaluation indicators,and the optimal molding technology was optimized.[Results]The extraction technology was soaking in water for 0.5 h and heat extraction twice for 1 h each time:adding 10 times the amount of water in the first time,and adding 8 times the amount of water in the second time.The best molding technology was:extract density 1.13-1.16(55-60℃),extract:soluble starch=1:2,and 0.15%stevioside.[Conclusions]The water extraction technology and granule molding technology optimized by orthogonal test are reliable and stable,with good granular characteristics,easy oral administration and good solubility,which can maximize the comprehensive quality of Wuwei Xiaoke granules,and provide an effective reference for the preparation and production of Wuwei Xiaoke granules. 展开更多
关键词 wuwei Xiaoke granule Orthogonal test Preparation technology
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Satisfactory Gansu with Charming Nature and Culture
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《China & The World Cultural Exchange》 2023年第9期26-27,共2页
From August 17 to 23,2023,the Yellow River Tourism Overseas Promotion Season 2023 launched the"Gansu Overseas Promotion Week"to present the Gansu Cultural Tourism Promotional Video,Gansu Intangible Cultural ... From August 17 to 23,2023,the Yellow River Tourism Overseas Promotion Season 2023 launched the"Gansu Overseas Promotion Week"to present the Gansu Cultural Tourism Promotional Video,Gansu Intangible Cultural Heritage Short Video and the"Symphony Silk Road and Satisfactory Gansu"-Gansu in Chinese Folk Music series of short videos to the global public. 展开更多
关键词 gansu SYMPHONY FACTORY
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Evaluation of Water Resources Carrying Capacity in Gansu Section of Yellow River Basin Based on Fuzzy Comprehensive Evaluation Model
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作者 Shuanbao LIN 《Meteorological and Environmental Research》 CAS 2023年第4期42-45,49,共5页
As a basic natural resource and strategic economic resource,the development and utilization of water resources is an important issue related to the national economy and people's livelihood.How to scientifically ev... As a basic natural resource and strategic economic resource,the development and utilization of water resources is an important issue related to the national economy and people's livelihood.How to scientifically evaluate the water resources carrying capacity is the premise to improve the regional water resources carrying capacity and ensure the regional water security.The Gansu section of the Yellow River basin is an important water conservation and recharge area.Whether the water resources in this area can ensure the normal operation of the ecosystem and whether it can carry the sustainable development of social economy is the key to realize the high-quality development of the Yellow River basin.In this study,from the three dimensions of water consumption per capita,water consumption of 10000 yuan GDP and ecological water use rate,by constructing the evaluation index system and index grading standard of water resources carrying capacity,the fuzzy comprehensive evaluation model was used to evaluate the water resources carrying capacity of Gansu section of the Yellow River Basin,in order to provide theoretical decision-making basis for the comprehensive development,utilization and planning management of water resources in Gansu section of the Yellow River basin and even the whole basin,and help the high-quality development of the Yellow River basin. 展开更多
关键词 Fuzzy comprehensive evaluation model Water resources carrying capacity EVALUATION Yellow River basin gansu section
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A Study on the Chess Culture of Ethnic Minority Groups in Gansu Province
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作者 Ying’an Wang Xiaoming Ma 《Open Journal of Applied Sciences》 2023年第12期2360-2370,共11页
As a region inhabited by large populations of ethnic minority groups, Gansu province boasts rich ethnic cultural resources which reflect traditional culture and intangible cultural heritage that had taken shape thousa... As a region inhabited by large populations of ethnic minority groups, Gansu province boasts rich ethnic cultural resources which reflect traditional culture and intangible cultural heritage that had taken shape thousands of years ago. Among these are various ethnic folk chess games. They are time-honored with many types such as the “Fang” chess of the Hui ethnic group, the “Jiu” chess of the Tibetans, the “King and Ministers” chess, the Mongolian chess, the Mongolian military chess, etc. These games embody distinctive ethnic and regional characteristics, as well as the cultural elements of a particular ethnic minority group. It is of great significance, therefore, to study the ethnic chess by collecting, documenting and comparing different types of related chess. The paper explores ways to standardize, protect and promote them scientifically in joint efforts, and draws a conclusion that examining their significance in the present era and the ethnic characteristics is the key to understanding the profound culture behind the chess. 展开更多
关键词 Ethnic Minority Groups in gansu Province Chess Culture A Study
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H9N2亚型禽流感病毒A/Chicken/Gansu/2/99株基因组的分子特征 被引量:7
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作者 独军政 侯顺利 +3 位作者 易华山 付生芳 常惠芸 才学鹏 《中国人兽共患病学报》 CAS CSCD 北大核心 2008年第6期543-547,共5页
目的测定H9N2亚型禽流感病毒A/Chicken/Gansu/2/99(CK/GS/2/99)分离株的基因组序列并与参考毒株进行同源性分析,阐明该毒株的遗传变异及分子特征。方法采集发病鸡泄殖腔样品,经鸡胚尿囊腔接种分离病毒,采用RT-PCR方法对CK/GS/2/99株的8... 目的测定H9N2亚型禽流感病毒A/Chicken/Gansu/2/99(CK/GS/2/99)分离株的基因组序列并与参考毒株进行同源性分析,阐明该毒株的遗传变异及分子特征。方法采集发病鸡泄殖腔样品,经鸡胚尿囊腔接种分离病毒,采用RT-PCR方法对CK/GS/2/99株的8个分节段基因进行扩增,分别将其克隆到pGEM-T easy载体后进行序列测定与同源性分析。结果CK/GS/2/99株PB2、PB1、PA、HA、NP、NA、M、NS基因的开放阅读框分别由2280、2274、2151、1683、1497、1401、759、864个碱基组成,分别编码759、757、716、560、498、466、252/97、231/122个氨基酸残基。该毒株HA上HA1和HA2裂解位点序列为PARSSR↓GLF,具有典型的低致病性禽流感病毒的特征。同源性分析显示,CK/GS/2/99株与1998-2002年间大部分中国大陆分离株遗传关系较近,尤其与CK/NX/4/99和CK/HB/31/00株遗传关系密切。结论CK/GS/2/99与大部分流行于中国内陆的H9N2亚型毒株均来源于共同的祖先毒株CK/BJ/1/94,这为了解中国H9N2亚型禽流感病毒的分子流行病学提供了资料。 展开更多
关键词 禽流感病毒 H9N2亚型 A/Chicken/gansu/2/99 序列分析
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Hand in Hand East and West to Build a Glorious Gansu——Talk on the cooperation between the East and West of China by Mr.Cui Zhenghua,vice governor of Gansu Province
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作者 Xiao Qiang,staff reporter 《China's Foreign Trade》 1996年第11期16-16,共1页
To implement the CPC CentralCommittee’s strategy of slanting theeconomic construction to the Midand West of China and to further promote thedevelopment and cooperation of economyand trade between the East and West, t... To implement the CPC CentralCommittee’s strategy of slanting theeconomic construction to the Midand West of China and to further promote thedevelopment and cooperation of economyand trade between the East and West, theEast-West Business and Trade Talks wereheld by the China Council for the Promotionof International Trade (CCPIT). At theconference, Mr. Cui Zhenghua, vice governorof Gansu Province and concurrently chairmanof the Gansu Subcouncil of the CCPIT,delivered a speech on the economiccooperation and development between theEast and West of China. 展开更多
关键词 West In Hand in Hand East and West to Build a Glorious gansu Talk on the cooperation between the East and West of China by Mr.Cui Zhenghua vice governor of gansu Province
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Sequence of the Cenozoic Mammalian Faunas of the Linxia Basin in Gansu, China 被引量:18
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作者 DENGTao WANGXiaoming +1 位作者 NIXijun LIULiping 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第1期8-14,共7页
In the Linxia Basin on the northeast margin of the Tibetan Plateau, the Cenozoic strata are very thick and well exposed. Abundant mammalian fossils are discovered in the deposits from the Late Oligocene to the Early P... In the Linxia Basin on the northeast margin of the Tibetan Plateau, the Cenozoic strata are very thick and well exposed. Abundant mammalian fossils are discovered in the deposits from the Late Oligocene to the Early Pleistocene. The Dzungariotherium fauna comes from the sandstones of the Jiaozigou Formation, including many representative Late Oligocene taxa. The Platybelodon fauna comes from the sandstones of the Dongxiang Formation and the conglomerates of the Laogou Formation, and its fossils are typical Middle Miocene forms, such as Hemicyon, Amphicyon, Platybelodon, Choerolophodon, Anchitherium, and Hispanotherium. The Hipparion fauna comes from the red clay of the Liushu and Hewangjia Formations, and its fossils can be distinctly divided into four levels, including three Late Miocene levels and one Early Pliocene level. In the Linxia Basin, the Hipparion fauna has the richest mammalian fossils. The Equus fauna comes from the Wucheng Loess, and it is slightly older than that of the classical Early Pleistocene Nihewan Fauna. The mammalian faunas from the Linxia Basin provide the reliable evidence to divide the Cenozoic strata of this basin and correlate them with European mammalian sequence. 展开更多
关键词 Linxia Basin CENOZOIC STRATIGRAPHY mammalian fossil gansu China
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On a New Genus of Basal Neoceratopsian Dinosaur from the Early Cretaceous of Gansu Province, China 被引量:13
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作者 YOU Hailu LI Daqing +2 位作者 JI Qiang Matthew C. LAMANNA Peter DODSON 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2005年第5期593-597,共5页
A new genus and species of basal neoceratopsian dinosaur, Auroraceratops rugosus, is reported based on material from the Early Cretaceous Xinminpu Group in the Gongpoquan Basin of Gansu Province, China. Auroraceratops... A new genus and species of basal neoceratopsian dinosaur, Auroraceratops rugosus, is reported based on material from the Early Cretaceous Xinminpu Group in the Gongpoquan Basin of Gansu Province, China. Auroraceratops is represented by a nearly complete skull and low jaws, and different greatly from all other neoceratopsians by its considerable breadth of the nasals, fungi form expansion of the dorsal end of the lacrimal, highly developed rugosity of the jugal, dentary and surangular, and inflated, striated premaxillary teeth. The finding of Auroraceratops adds diversity and helps elucidate the evolution of basal neoceratopsian dinosaurs. 展开更多
关键词 DINOSAURIA Neoceratopsia Early Cretaceous Xinminpu Group Gongpoquan Basin gansu Province
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U-Pb SHRIMP Dating of Zircon from Quartz Veins of the Yangshan Gold Deposit in Gansu Province and Its Geological Significance 被引量:14
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作者 QIJinzhong YUANShisong +5 位作者 LIUZhijie LIUDunyi WANGYanbin LIZhihong GUOJunhua SUNBin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第2期443-451,共9页
The Yangshan gold deposit is a super-large fine-grained disseminated gold deposit located in southern Gansu Province. Its metallogenic age has been determined by using the cathodoluminescence image and ion probe U-Pb ... The Yangshan gold deposit is a super-large fine-grained disseminated gold deposit located in southern Gansu Province. Its metallogenic age has been determined by using the cathodoluminescence image and ion probe U-Pb dating techniques. It is found that zircons from quartz veinlet of the fine-grained disseminated gold ore show characters of magmatic origin with prism idiomorphism, oscillatory zoning and dominant Th/U ratios of 0.5-1.5. Three main populations of zircons are obtained, giving average 206Pb/238U ages of 197.6±1.7 Ma, 126.9±3.2 Ma and 51.2±1.3 Ma respectively. The first age corresponds to the K-Ar age of the plagiogranite dike, while the latter two ages indicate that buried Cretaceous and Tertiary intrusives exist in the orefield, suggesting that the Yangshan gold deposit was genetically related to the three magmatic hydrothermal activities. By contrast, zircons from coarse gold-bearing quartz vein in the mining area are much older than the host rock, indicating that the vein was formed earlier and was not contaminated by later magmatic fluids. It is concluded that the coupling of multiperiodic hydrothermal activities in the mining area has contributed a lot to mineralization of the Yangshan gold deposit. 展开更多
关键词 disseminated type gold deposit quartz vein SHRIMP dating cathodoluminescence image gansu
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Cancer incidence and mortality in Gansu province,2012 被引量:5
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作者 yuqin liu xiaodong zhang +2 位作者 lili chen qin zhao xiaojun xia 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2016年第3期301-310,共10页
Objective: Population-based cancer registration data in 2012 from all available cancer registries in Gansu province were collected by the Central Cancer Registry of Gansu. The numbers of new cancer cases and cancer d... Objective: Population-based cancer registration data in 2012 from all available cancer registries in Gansu province were collected by the Central Cancer Registry of Gansu. The numbers of new cancer cases and cancer deaths in Gansu province with compiled cancer incidence and mortality rates were estimated. Methods: In 2015, data from 7 registries in Gansu province were qualified. The pooled data were stratified by area (urban/rural), gender, age group (0, 1-4, 5-9, 10-14, ..., 85+) and cancer type. New cancer cases and deaths were estimated using age-specific rates and corresponding population of Gansu province in 2012. The Chinese census data in 2000 and Segi's population were applied for age-standardized rates. All the rates were expressed per 100,000 person-years. Results: Qualified 7 cancer registries (3 urban and 4 rural registries) covered 2,956,560 populations of Gansu province in 2012. The percentage of cases morphologically verified (MV%) and death certificate-only cases (DCO%) were 72.41% and 1.65%, respectively, and the mortality to incidence rate ratio (M/I) was 0.63. It was estimated that there were 575,600 new cancer cases and 331,300 cancer deaths in Gansu province in 2012. The incidence rate was 223.29/100,000 (244.14/100,000 in males and 201.50/100,000 in females), the age-standardized incidence rates by Chinese standard population (ASIRC) and by world standard population (ASIRVv') were 208.95/100,000 and 206.41/100,000 with the cumulative incidence rate (0-74 years old) of 22.49%. The crude incidence rate in urban areas was equal to that in rural areas. However, after adjusted by age, the cancer incidence rate in urban was the same as that of rural areas. The crude mortality in Gansu province was 128.54/100,000 (135.04/100,000 in males and 124.43/100,000 in females), the age-standardized mortality rates by Chinese standard population (ASMRC) and by world standard population (ASMRW) were 109.54/100,000 and 108.44/100,000, respectively, and the cumulative mortality rate (0-74 years old) was 12.91%. The crude cancer mortality rate in urban areas was higher than that of rural areas. However, the age- standardized rate in urban areas was the same as that of rural areas. Cancers of stomach, liver, lung, esophagus, female breast, colorectum, cervix, brain, pancreas and ovary were the most common cancers, accounting for about 83.56% of all cancer new cases. Stomach cancer, liver cancer, lung cancer, esophageal cancer, female breast cancer, colorectal cancer, brain cancer, lymphoma, pancreatic cancer and cervix cancer were the leading causes of cancer death, accounting for about 85.58% of all cancer deaths. The burden between urban and rural, males and females was different. Conclusions: Registration data of Gansu province were qualified to provide basic information on population-based cancer incidence, mortality for cancer prevention and control. The digestive tract cancer burden in Gansu province, especially for males in rural areas, was higher. The incidence rate of female breast cancer was higher in urban areas. Targeted prevention, early detection and treatment programs should be carried out by health department to control the cancer burden. 展开更多
关键词 Cancer registry INCIDENCE MORTALITY EPIDEMIOLOGY gansu province
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A New Hadrosauriform Dinosaur from the Early Cretaceous of Gansu Province,China 被引量:8
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作者 YOU Hailu LI Daqing LIU Weichang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第1期51-57,共7页
A new basal hadrosauriform dinosaur, Xuwulongyueluni gen. et sp. nov., is reported based on an articulated specimen including a complete cranium, almost complete axial skeleton, and complete left pelvic girdle. The sp... A new basal hadrosauriform dinosaur, Xuwulongyueluni gen. et sp. nov., is reported based on an articulated specimen including a complete cranium, almost complete axial skeleton, and complete left pelvic girdle. The specimen is recovered from the Early Cretaceous Yujingzi Basin in the Jiuquan area, Gansu Province of northwestern China. Xuwulong is among the most basal members of hadrosauriform dinosaurs, and distinguished by its unique lower jaw in having a V-shaped rostral end of the dentary in lateral view and a mandibular articular surface which levels with mid-height of the dentary ramus, as well as an enlarged and downturned prepubic process. Including Xuwulong, three basal hadrosauriforms have been discovered from the Early Cretaceous Xinminpu Group in the Mazongshan area, making it an important area to study the origin and early evolution of duck-billed dinosaurs. 展开更多
关键词 DINOSAUR hadrosauriform gen. et sp. nov. Early Cretaceous Xinminpu Group gansu
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Cuticles and Spores in Situ of Coniopteris hymenophylloides from the Middle Jurassic in Gansu, Northwestern China 被引量:5
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作者 XIN Cunlin WANG Luhan +2 位作者 DU Baoxia ZHANG Yamei WANG Jingjing 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第3期904-914,共11页
Coniopteris was a ubiquitous plant of the Jurassic and Cretaceous periods and played an important role in the flora of the time. However, its anatomical structure is relatively poorly known. The specimens of Coniopter... Coniopteris was a ubiquitous plant of the Jurassic and Cretaceous periods and played an important role in the flora of the time. However, its anatomical structure is relatively poorly known. The specimens of Coniopteris hymenophylloides(Brongniart) Seward described here were collected from the Yaojie Formation in Gansu Province, northwestern China. The sterile fronds are characterized as being at least bipinnate with alternate arranged linear pinnae covered by thin cuticles. Fertile fronds are linear-lanceolate, with single sorus at the margin of each fertile pinnule. In situ spores are typically trilete, triangle to subcircular in polar view, cap-shaped in equatorial view, and 37 μm in average diameter. The trilete marking is straight and narrow, generally extends to 4/5 of the spore radius. The spore surface is smooth, and parts of the exine are granulated. The epidermal cells of cuticles are irregular in shape, approximately 40-60μm long and 10-20 μm wide. The elliptical stomatal complexes are paracytic,approximately 30 μm long and 19 μm wide,and irregularly distributed. On the basis of its epidermal structures and comparisons with extant ferns, we consider that Coniopteris displays combined features of the related extant genera. 展开更多
关键词 Coniopteris hymenophylloides spore in situ cuticle Middle Jurassic Yaojie Formation gansu China
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Forest biomass carbon storage from multiple inventories over the past 30 years in Gansu Province, China: implications from the age structure of major forest types 被引量:5
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作者 Jinhong Guan Huanshui Zhou +2 位作者 Lei Deng Jianguo Zhang Sheng Du 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第4期887-896,共10页
We used the forest inventory data of Gansu Province, China to quantify carbon storage and carbon density changes by regional forest cover and by typical forest types in 1979-2006. Total forest area increased from 1.77... We used the forest inventory data of Gansu Province, China to quantify carbon storage and carbon density changes by regional forest cover and by typical forest types in 1979-2006. Total forest area increased from 1.77 x 106 ha in 1979 to 2.32 x 106 ha in 2006, and the forest carbon storage, estimated by the continuous biomass expansion factor method, increased from 83.14 to 100.66 Tg, equivalent to a carbon accumulation rate of 0.0071 Tg per year during the period. Mean carbon densities were 44.83-48.50 t ha-1 and the values decreased slightly over the time period. Natural forests generated greater car- bon storage and density than did plantations. By regression analysis, forest stand age was an important parameter incarbon density studies. We developed various regression equations between carbon density and stand age for major types of natural forests and plantations in the region. Our results can be used for proper selection of re-forestation species and efficient management of young and middle-aged forests, offering great potential for future carbon sequestra- tion, especially in arid and semi-arid regions. 展开更多
关键词 Age class Carbon density Forest carbonstorage Forest inventory data gansu Province REFORESTATION
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Palynology of Yanchang Formation of Middle and Late Triassic in Eastern Gansu Province and Its Paleoclimatic Significance 被引量:5
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作者 吉利明 孟凡巍 《Journal of China University of Geosciences》 SCIE CSCD 2006年第3期209-220,共12页
Xifeng (西峰) oilfield was recently found in the southwest of the Ordos basin. The oil source rocks are the Chang 7 Section of Yanchang (延长) Formation. In order to study the paleoclimate that controlled the form... Xifeng (西峰) oilfield was recently found in the southwest of the Ordos basin. The oil source rocks are the Chang 7 Section of Yanchang (延长) Formation. In order to study the paleoclimate that controlled the formation of source rocks, a systemically palynological research on related beds in Yanchang Formation has been carried out. The core samples were analyzed with classical palynological techniques and the organic-walled sporomorphs from these samples were observed, identified and photographed under a light microscopy and a fluorescence microscopy. Abundant sporopollen were found in drilling cores from Chang 8 and Chang 7 sections, and two assemblages were distinguished: the Aratisporites-Punctatisporites assemblage and the Asseretospora-Walchiites assemblage. Their characteristics are similar to those of the assemblage of Tongchuan (铜川 ) Formation and the assemblage of Yanchang Formation in southeast Ordos basin, respectively. Their geological times are Ladinian of late Middle Triassic and Carnian of early Late Triassic, respectively. The correlation of palynoflora with their parent plants suggests the paleoclimate of eastern Gansu (甘肃) Province in the Middle and Late Triassic was warm and rainy with prosperous vegetation. The palynoflora indicated the area was in a temperate to subtropical zone then. Both the ecological types and differentiation degree curves of sporopollen indicated the period during Chang 8 and Chang 7 sections was warm and wet, and the phase accorded with large-scale lake transgression in Chang 8 Section and the largest lake area in Chang 7 Section. North China in Middle and Late Triassic was located in a warm and rainy, temperate and subtropi- cal zone. The palynofloras in Chang 8 and Chang 7 sections have the characteristics of North China flora, however they also indicate wetter and warmer climate due to their proximity to the large lakes. The period of Chang 8 to Chang 7 sections is the climax of the expansion of the lake, and the bloom of fresh algae during the period, which helped form the high-quality source rocks in Chang 7 Section. 展开更多
关键词 Ordos basin eastern gansu Province Yanchang Formation source rock sporopollen assemblage paleoclimate.
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Study on growing correlation length prior to the earthquakes occurred in Gansu Province and its nearby area 被引量:3
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作者 RONG Dai-lu(荣代潞) +3 位作者 LI Ya-rong(李亚荣) LIU Xu-zhou(刘旭宙) 《Acta Seismologica Sinica(English Edition)》 CSCD 2004年第5期564-570,共8页
The growing correlation length prior to the moderate-great earthquakes occurred in Gansu Province and its nearby area since 1986 has been studied using the method of single-link cluster analysis (SLC). According to di... The growing correlation length prior to the moderate-great earthquakes occurred in Gansu Province and its nearby area since 1986 has been studied using the method of single-link cluster analysis (SLC). According to different conditions in the source area, the circular spatial window centered in the epicenter and the parallelgrammic spatial window along the fault belt have been selected. The results show that the phenomena of growing correlation length have been observed before the earthquakes studied in the paper. 展开更多
关键词 moderate-great earthquake correlation length single-link cluster analysis gansu
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Emergy-based study on eco-economic system of arid and semi-arid region:a case of Gansu province,China 被引量:5
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作者 Xue, Bing Chen, XingPeng +3 位作者 Geng, Yong Yang, Mian Yang, FuXia Hu, XiaoFen 《Journal of Arid Land》 SCIE 2010年第3期207-213,共7页
关键词 emergy analysis economic geography regional sustainable development arid and semi-arid area gansu province
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