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1Reconstruction of precipitation variation from tree rings in recent 1000 years in Delingha, Qinghai显示文摘Using seven well-replicated Qilian juniper (Sabina przewalskii Kom.) ring-width chronologies developed at Zongwulong and Shalike Mts. in the northeastern part of the Qaidam Basin annual precipitation from previous July to current June in the recent 1000 years was re- constructed for Delingha. The reconstruction can capture 63.1% of precipitation variance and the equation was stable over time. For the reconstructed precipitation, wet periods occurred in AD1520—1633 and 1933—2001, whereas dry intervals in 1429—1519 and 1634—1741. In ad- dition, the magnitude in precipitation variation was lower before 1430 with about 15 mm, but it increased to 30 mm during the period of 1430 to 1850. After 1850, the precipitation variance de- creased again. In contrast to the increase in temperature, a decrease in annual precipitation was evident since the 1990s. The agreement in low-frequency variation between the reconstruction and the glacier accumulation and particulate content in Dunde ice cores during the recent several hundred years suggested that the precipitation reconstructed in this study was rather reliable, and represented a regional signal. This 1000-year reconstruction could benefit our understanding of climatic variation in decadal to century-scale in this region, and provide basic data to climate models and to prediction of future climate in the 21st century.SHAO Xuemei1, HUANG Lei1, LIU Hongbin2, LIANG Eryuan1, FANG Xiuqi3 & WANG Lili1 1. Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China 2. National Climate Center, Beijing 100081, China 3. Beijing Normal University, Beijing 100875, China 2005Science China Earth Sciences2005,48,7:113
2下肢深静脉血栓形成治疗和预后的几个问题显示文摘对下肢深静脉血栓形成(deep venous thrombosis of the lower limbs,DVT)的认识已近200年的历史,1810年Farriar首先报道1例,其后Davis指出股白肿由DVT引起并与分娩有关。20世纪30年代以前,主要治疗方法是卧床休息和抬高患肢;60年代,手术取栓、抗凝与溶栓治疗相继用于临床。导管直接溶栓(catheter directed thrombolysis)、张柏根 2006中华普通外科杂志2006,21,2:115
3Stable classi?cation with limited sample: transferring a 30-m resolution sample set collected in 2015 to mapping 10-m resolution global land cover in 2017显示文摘As the world strives to reduce the impact of population growth, urbanization, agricultural expansion, and climate change on food security, energy and water shortage, resource over-exploration, biodiversity loss, environmental pollution, and ultimately human health, timely and higher resolution land cover information is urgently needed to achieve the sustainable development goals of the United Nations.Peng Gong Han Liu Meinan Zhang Congcong Li Jie Wang Huabing Huang Nicholas Clinton Luyan Ji Wenyu Li Yuqi Bai Bin Chen Bing Xu Zhiliang Zhu Cui Yuan Hoi Ping Suen Jing Guo Nan Xu Weijia Li Yuanyuan Zhao Jun Yang Chaoqing Yu Xi Wang Haohuan Fu Le Yu Iryna Dronova Fengming Hui Xiao Cheng Xueli Shi Fengjin Xiao Qiufeng Liu Lianchun Song 2019Science Bulletin2019,64,6:166
4Estimation on the response of glaciers in China to the global warming in the 21st century显示文摘Glaciers in China can be categorized into 3 types, i.e. the maritime (temperate) type, sub-continental (sub-polar) type and extreme Continental (polar) type, which take 22%, 46% and 32% of the total existing glacier area (59 406 km2) respectively. Researches indicate that glaciers of the three types show different response patterns to the global warming. Since the Maxima of the Little Ice Age (the 17th century), air temperature has risen at a magnitude of 1.3℃on average and the glacier area decreased corresponds to 20% of the present total glacier area in western China. it is estimated that air temperature rise in the 2030s, 2070s and 2100s will be of the order of 0.4-1.2, 1.2-2.7 and 2.1-4.0 K in western China. With these scenarios, glaciers in China will suffer from further shrinkage by 12%, 28% and 45% by the 2030s, 2070s and 2100s. The uncertainties may account for 30%-67% in 2100 in China.SHI Yafeng & LIU Shiyin Laboratory of Ice Core and Cold Regions Environment, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China 2000Chinese Science Bulletin2000,45,7:71
5Geomorphologic evidence of phased uplift of the northeastern Qinghai-Tibet Plateau since 14 million years ago显示文摘A typical sequence of fluvial terraces and aeolian deposits overlying these terraces were multidisciplinary investigated. New evidences for uplift process of the northeastern Qinghai-Tibetan Plateau in the past 14 million years were obtained. At least 11 river terraces along Huangshui, the first-class tributary of Yellow River, at the Xining-Huzhu region are identified. While the first one (T1) is classified as an accumulation terrace, the others are all basement river terraces, which consist of the Tertiary sandstone and siltstone bedrock, fluvial gravel and pebbles and the overlying aeolian loess-Red Clay deposit. Samples from the aeolian deposits were examined for paleomagnetic stratigraphic reconstruction (1030 samples), luminescence dating (16 samples), magnetic susceptibility and grain-size distribution (more than 4000 samples). The luminescence dating and stratigraphic correlation suggest that terraces of T11, T10,T8, T7, T3, T2, T1 were formed at 14, 11.3, 1.55, 1.2, 0.15, 0.07 and 0.01 million years ago, respectively. Sedimentological analysis and geomorphological observation indicate that formation and evolution of these terraces were mainly driven by tectonic uplift. Therefore, the terrace sequence provides an ideal geological record of the uplift process of the northeastern Qinghai-Tibet during the past 14 million years, and the timings of the terraces formation are regarded as the timings of tectonic uplift. The significant uplifting events took place at 14, 11.3, 1.2 and 0.15 million years ago, respectively. The fluvial incision at the Xining-Huzhu region is less than 100 m during a period of ~12 million years in the Miocene era (between the T11 and T9), while the Huangshui River had incised 432 m during the past 1.2 million years (from T7 to the present floodplain). The river incision process clearly demonstrates that accelerated rising of the northeastern Qinghai-Tibet Plateau during the late Cenozoic, and provides new evidence of previous thoughts. There was a significant readjustment of the fluvial catchment during 1.55-1.2 million years ago: before this time, the paleoriver flowed to southwest. After this time the Huangshui River flows to southeast. A tectonic movement dominates reorganization of this fluvial system.LU Huayu1, WANG Xiaoyong1, AN Zhisheng1, MIAO Xiaodong1, ZHU Rixiang3, MA Haizhou2, LI Zhen4, TAN Hongbing2 & WANG Xianyan1 1. State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075 China 2. Qinghai Institute of Salt Lakes, Chinese Academy of Sciences. Xining 810008, China 3. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 4. Department of Geography, Qinghai Normal University, Xining 810008, China 2004Science China Earth Sciences2004,47,9:51
6Expression of nuclear factor-KB in hepatocellular carcinoma and its relation with the X protein of hepatitis B virus显示文摘AIM In this study we investigated therelationship of the X protein of HBV and nuclearfactor-KB (NF-κB) and the expression of NF-KB inhuman hepatocellular carcinoma tissues.METHODS Immunohistochemistry SP methodwas used to detect the expression of NF-κB and the X protein of HBV in human hepatocellularcarcinoma tissues of 52 cases. Gene transfectionmediated by lipofectamine was used to transfectthe eukaryotic expression vector pCDNA3. 1-HBXof HBV x gene into human hepatocellularcarcinoma cell line HCC-9204 and NF-κB wasdetected.RESULTS NF-κB was widely expressed inhuman hepatocellular carcinoma tissues in atotal of 52 cases and its expression was relatedto the X protein of HBV. NF-KB was localizedboth in the cytoplasm and . The nuclei ofhepatocellular carcinoma cells in 11 cases whichwere positive for the X protein of HBV while in 41cases negative for the X protein of HBV, NF-Kbwas only localized in the cytoplasm ofhepatocellular carcinoma cells but translocatedto the nuclei of hepatocellular carcinoma cellsafter the eukaryotic expression vectorpCDNA3.1-HBX was transfected into HCC-9204cells.CONCLUSION This study strongly suggeststhat the nuclear factor NF-KB is widely expressedin hepatocellular carcinoma tissues in differentstyles according to the expression of the Xprotein of HBV. NF-κB is abnormally activated inhepatocellular carcinoma, which is probablyrelated to the X protein of HBV. The X protein ofHBV can activate NF-κB to translocate into nucleiof hepatocellular carcinoma cells.Shuang Ping Guo~1 Wen Liang Wang~1 Yu Qiang Zhai~2 Yi Ling Zhao~1 ~1Department of Pathology,Xijing Hospital of the Fourth Military Medical University,Xi’an,China ~2Department of Urology,the Central Hospital of Xi’an,China 2001World Journal of Gastroenterology2001,7,3:55
7Influence of the impounding process of the Three Gorges Reservoir up to water level 172.5m on water eutrophication in the Xiangxi Bay显示文摘The water level of the Three Gorges Reservoir(TGR) rose to 172.5 m in two stages from September to November,2008.The hydrodynamic parameters and water quality parameters(e.g.flow velocity,temperature,turbidity and nutrient content) had been continuously monitored to reveal the influence of the impounding process of the TGR on the water eutrophication in the Xiangxi Bay(XXB).The maximal daily rise of the water level of the TGR was about 2.38 m.The water exchange between the mainstream(the Changjiang River) and the XXB of the TGR was enhanced by density current,and its main characteristics were a density-stratified flow in different directions.The water exchange reduced the differences of the water quality parameters(for example,temperature,turbidity,nutrient level,pH,etc.) between the mainstream and the XXB during the impounding process.Meanwhile,the water stability index in the mainstream remained small but it was lowered in the XXB.The main causes included the dilution by water of lower concentration of the chlorophyll a(Chl.a) entering from the mainstream,the decline of the water stability,and the increase of suspended silt,which induced the Chl.a to decrease in the XXB during the impounding process.The grade of the water eutrophication changed from middle eutrophic level to mesotrophic state in the process.However,as available nutrients were imported into the XXB from the mainstream during the impounding process the risk of water eutrophication increases in the XXB in the future.YANG ZhengJian1,LIU DeFu1,JI DaoBin1,2 & XIAO ShangBin1,3 1 College of Civil & Hydroelectric Engineering,China Three Gorges University,Yichang 443002,China 2 School of Water Resources & Hydropower Engineering,Wuhan University,Wuhan 430072,China 3 Institute of Earth Environment,Chinese Academy of Sciences,Xi’an 710075,China 2010Science China(Technological Sciences)2010,53,4:58
8Geomorphological and environmental evolution in the upper reaches of the Yellow River during the late Cenozoic显示文摘Studies of the geomorphology and stratigraphy in the upper reaches of the Yellow River during the late Cenozoic demonstrate that the period of 30 - 3.4 Ma is characterized by a relatively stable tectonic setting, a persistently hot climate and a wide distribution of inland basins. This long-term stable environment resulted in a planation surface, the main surface on the Qinghai-Xizang (Qingzang) Plateau, on which red earth crust and karst arc formed. Since 3.4 Ma, the Qingzang Plateau was 'uplifted as a whole massif, accompanied by the dissection and disintegration of the main surface, termination of deposition and deformation of stratigraphy in red basins, increasing relief and commencing accumulation of inland molasse formation mainly of conglomerate. Subsequent strong uplift of the Qingzang Plateau at 2.5 Ma and 1.7-1.66 Ma led to cormation of the basic geomorphological configuration of the Qingzang Plateau and occurrence of the Yellow River. These three strong uplifts of the Qingzang Plateau李吉均 方小敏 马海州 朱俊杰 潘保田 陈怀录 1996Science China Earth Sciences1996,39,4:53
9Developmental dysplasia of the hip: What has changed in the last 20 years?显示文摘Developmental dysplasia of the hip(DDH) describes the spectrum of structural abnormalities that involve the growing hip. Early diagnosis and treatment is critical to provide the best possible functional outcome. Persistence of hip dysplasia into adolescence and adulthood may result in abnormal gait, decreased strength and increased rate of degenerative hip and knee joint disease. Despite efforts to recognize and treat all cases of DDH soon after birth, diagnosis is delayed in some children, and outcomes deteriorate with increasing delay of presentation. Different screening programs for DDH were implicated. The suspicion is raised based on a physical examination soon after birth. Radiography and ultrasonography are used to confirm the diagnosis. The role of other imaging modalities, such as magnetic resonance imaging, is still undetermined; however, extensive research is underway on this subject. Treatment depends on the age of the patient and the reducibility of the hip joint. At an early age and up to 6 mo, the main treatment is an abduction brace like the Pavlik harness. If this fails, closed reduction and spica casting is usually done. After the age of 18 mo, treatment usually consists of open reduction and hip reconstruction surgery. Various treatment protocols have been proposed. We summarize the current practice for detection and treatment of DDH, emphasizing updates in screening and treatment during the last two decades.Pavel Kotlarsky Reuben Haber Victor Bialik Mark Eidelman 2015World Journal of Orthopedics2015,6,11:52
10Precipitation variation in the northeastern Tibetan Plateau recorded by the tree rings since 850 AD and its relevance to the Northern Hemisphere temperature显示文摘Three well-dated Sabina Przewalskii ring-width chronologies from Dulan, China, have been used to reconstruct annual precipitation (from prior July to current June) variations on the northeast Tibetan Plateau since 850 AD. The reconstructions account of the instrumentally recorded precipitation variance are: 54.7% for the period of 1385-2000AD; 50.5% for 1099-1384AD and 45.7% for 850-1098AD. On the millenary scale, the precipitation variation over this region displays “W” shape, which has three peaks and two valleys. The precipitation is low during 1571-1879 AD, and high during 1880-2000 AD. 1900-2000 AD is the century with the highest precipitation over the northeast Tibetan Plateau in the last 1000 years, and 1962-2000 is the period with the highest pre- cipitation, and the highest variability of precipitation as well in the last 1000 years. The reconstructed series also reveals that the variability of annual precipitation is large when the precipitation is more, and contrarily, variability is small when the precipitation is low. With the temperature increasing obvi- ously in the 20th century, the precipitation in the study region significantly increased too, the variability of precipitation became larger, and drought and flooding occurred more frequently. The yearly tree-ring width (high frequency signal) series in this region reflects the local annually precipitation variation. However, the series with 40-year moving average (low frequency signal) cor- responds to the Northern Hemisphere temperature variations on the decadal to centurial scale. It correlates significantly with seven temperature curves of the Northern Hemisphere in the different time spans. For example, the correlation coefficients with the most temperature curves are around 0.9 during the period of 1852-1982 AD. In general, the temperature and the precipitation change syn- chronously in the Dulan region. It means that low temperature corresponds to low precipitation, andvice versa. This relationship may indicate that the climatic pattern is the combination of warm-wet and cold-dry on centenary to millenary scale over the Northern Tibetan Plateau in the past 1000 years. The departure series of 40-year moving average could be regarded as the millenarian temperature curve with annual resolution over the northeast Tibetan Plateau region.John K. Kutzbach 2006Science China Earth Sciences2006,49,4:44
11肘关节严重损伤三联征显示文摘张世民 周家钤 俞光荣 2005中国矫形外科杂志2005,13,10:44
12Abstract from: Pharmacologic treatment of hypertension in adults aged 60 years or older to higher versus lower blood pressure targets: A clinical practice guideline from the American College of Physicians and the American Academy of Family Physicians显示文摘Description: The American College of Physicians (ACP) and the American Academy of Family Physicians (AAFP) jointly developed this guideline to present the evidence and provide clinical recommendations based on the benefits and harms of higher versus lower blood pressure targets for the treatment of hypertension in adults aged 60 years or older.Amir Qaseem Timothy J. Wilt Robert Rich Linda L. Humphrey Jennifer Frost Mary Ann Forciea 2017Chinese Nursing Research2017,4,4:43
13Why Lake Taihu continues to be plagued with cyanobacterial blooms through 10 years(2007–2017) efforts显示文摘With the expansion of urban, industry, and agriculture after World War II, eutrophication firstly emerged as a major water quality threat in small water bodies [1]. As the increasing magnitudes and scales of nutrient pollution and habitat alteration, many of the world's large lakes exhibit symptoms of eutrophication, e.g., toxic cyanobacterial blooms, deoxygenation, and habitat loss.Boqiang Qin Hans W.Paerl Justin D.Brookes Jianguo Liu Erik Jeppesen Guangwei Zhu Yunlin Zhang Hai Xu Kun Shi Jianming Deng 2019Science Bulletin2019,64,6:50
14Evidence for water exchange between the South China Sea and the Pacific Ocean through the Luzon Strait显示文摘An analysis of historical oxygen data provides evidence on the water exchange between the South China Sea(SCS)and the Pacific Ocean(PO).In the vicinity of the Luzon Strait(LS),the dissolved oxygen concentration of sea water is found to be lower on the Pacific side than on the SCS side at depths between 700 and 1500 rn(intermediate layer),while the situation is reversed above 700 rn(upper layer)and below 1 500 rn(deep layer).The evidence suggests that water exits the SCS in the intermediate layer but enters it from the Pacific in both the upper and the deep layers,supporting the earlier speculation that the Luzon Strait transport has a sandwiched structure in the vertical.Within the SCS basin,the oxygen distribution indicates widespread vertical rnovernent,including the upwelling in the intermediate layer and the downwelling in the deep layer.Qu Tangdong(曲堂栋) 2002Acta Oceanologica Sinica2002,21,2:40
15A numerical study of the South China Sea deep circulation and its relation to the Luzon Strait transport显示文摘A fine-resolution MOM code is used to study the South China Sea basin-scale circulation and its relation to the mass transport through the Luzon Strait. The modal domain includes the South China Sea, part of the East China Sea, and part of the Philippine Sea so that the currents in the vicinity of the Luzon Strait are free to evolve. In addition, all channels between the South China ,Sea and the Indonesian seas are closed so that the focus is on the Luzon Strait transport. The model is driven by specified Philippine Sea currents and by surface heat and salt flux conditions. For simplicity, no windstress is applied at the surface.The simulated Luzon Strait transport and the South China Sea circulation feature a sandwich vertical structure from the surface to the bottom. The Philippine Sea water is simulated to enter the South China Sea at the surface and in the deep ocean and is carried to the southern basin by western boundary currents. At the intermediate depth, the net Luzon Strait transport is out of the South China Sea and is fed by a western boundary current flowing to the north at the base of the thermocline. Corresponding to the western boundary currents, the basin circulation of the South China Sea is cyclonic gyres at the surface and in the abyss but an anti-cyclonic gyre at the intermediate depth. The vorticity balance of the gyre circulation is between the vortex stretching and the meridional change of the planetary vorticity.Based on these facts, it is hypothesized that the Luzon Strait transports are determined by the diapycnal mixing inside the entire South China Sea. The South China Sea plays the role of a 'mixing mill' that mixes the surface and deep waters to return them to the Luzon Strait at the intermediate depth. The gyre structures are consistent with the Stommel and Arons theory (1960), which suggests that the mixlng-induced circulation inside the South China Sea should be cyclonic gyres at the surface and at the bottom but an anti-cyclonic gyre at the intermediate depth. The simulated gyre circulation at the intermediate depth has been confirmed by the dynamic height calculation based on the Levitns hydrography data.The sandwich transports in the Luzon Strait are consistent with recent hydrographic, al observations.Model results suggest that the Kuroshio tends to form a loop current in the northeastern South China Sea. The simulated Kuroshio Loop Current is generated by the pressure head at the Pacific side of the Luzon Strait and is enhanced by theβ- plane effects. The β- plane appears to be of paramount importance to the South China Sea circulation and to the Luzon Strait translports. Without theβ-plane, the Luzon Strait transports would be greatly reduced and the South China Sea circulation would be complete-ly different.Yuan Dongliang1. Goddard Earth Science and Technology Center, University of Maryland, Baltimore County Code 971, Laboratory for Hydrospheric Processes, NASA/Goddard Space Flight Center, Greenbelt, MD 20771, USA 2002Acta Oceanologica Sinica2002,21,2:37
16Prediction of permafrost distribution on the Qinghai-Tibet Plateau in the next 50 and 100 years显示文摘Intergovernmental Panel on Climate Change (IPCC) in 2001 reported that the Earth air temperature would rise by 1.4-5.8℃ and 2.5℃ on average by the year 2100. China re-gional climate model results also showed that the air temperature on the Qinghai-Tibet Plateau (QTP) would increase by 2.2-2.6℃ in the next 50 years. A numerical permafrost model was developed to predict the changes of permafrost distribution on the QTP over the next 50 and 100 years under the two climatic warming scenarios, i.e. 0.02℃/a, the lower value of IPCC’s estima-tion, and 0.052℃/a, the higher value predicted by Qin et al. Simulation results show that ( i ) in the case of 0.02℃/a air-temperature rise, permafrost area on the QTP will shrink about 8.8% in the next 50 years, and high temperature permafrost with mean annual ground temperature (MAGT) higher than ?0.11℃ may turn into seasonal frozen soils. In the next 100 years, perma-frost with MAGT higher than ?0.5℃ will disappear and the permafrost area will shrink up to 13.4%. (ii) In the case of 0.052℃/a air-temperature rise, permafrost area on the QTP will reduce about 13.5% after 50 years. More remarkable degradation will take place after 100 years, and permafrost area will reduce about 46%. Permafrost with MAGT higher than ?2℃ will turn into seasonal frozen soils and even unfrozen soils.NAN Zhuotong LI Shuxun CHENG Guodong 2005Science China Earth Sciences2005,48,6:40
17Eolian evidence from the Chinese Loess Plateau: the onset of the Late Cenozoic Great Glaciation in the Northern Hemisphere and Qinghai-Xizang Plateau uplift forcing显示文摘On the basis of a newly-constructed record of magnetic susceptibility (SUS) and the depositional rate change of eolian loess-red clay sequences in the last 7.2 Ma BP from the Loess Plateau, together with a comparison of a record of δ18O values from the equatorial East Pacific Ocean and eolian Quartz flux variations from the North Pacific Ocean, the evolutionary process of the Late Cenozoic Great Glaciation in the Northern Hemisphere can be divided into three stages: the arrival stage around 7.2—3.4 Ma BP, the initial stage at about 3.4—2.6 Ma BP, and the Great Ice Age since 2.6 Ma BP. The evolution of the East Asian monsoon is characterized by paired winter and summer monsoons, and it is basically composed of the initial stage of weak winter and summer monsoons, the transitional stage of simuhaneous increase in intensity of winter and summer monsoons, and the prevailing stage of strong winter and weak summer monsoons, or weak winter and strong summer monsoons. The Late Cenozoic global tectonic安芷生 王苏民 吴锡浩 陈明扬 孙东怀 刘秀铭 王富葆 李力 孙有斌 周卫健 周杰 刘晓东 鹿化煜 张云翔 董光荣 强小科 1999Science China Earth Sciences1999,42,3:39
182004年国家级股骨头坏死最新治疗进展专题研讨会会议纪要显示文摘姜文学 2005实用骨科杂志2005,11,2:40
19英国急性胰腺炎诊治指南显示文摘刘占举 牛虹 柯楠 2005医学与哲学2005,26,10X:35
20精神疾病病耻感的精神动力学分析及对策显示文摘众所周知,在全球范围内,由精神疾病所引起的歧视及病耻感都是一个不容忽视的问题.对患有精神疾病的人而言,病耻感是其提高生活质量的最大障碍[1].为此,世界精神病协会(WPA)在1998年开展了'open the door'运动,希望能够引导公众重新认识精神病患者,以达到减轻病耻感和消除歧视的目的.许多精神病学家及社会心理学家也正在分析其根源,并试图寻求解决途径.本文就时下主要研究及观点做一综述.俞峻瀚 肖泽萍 2005上海精神医学2005,17,6:35
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