检索结果-南通市图书馆

Theoretical research progress in new-generation Internet architecture

在线全文

学校读者我要写书评

暂无评论

Science in china(Series F) 2008年第11期51卷 1634-1660页

作者： WU JianPing1,2,3.LIU Ying2,3.& WU Qian2,3.1 Department of Computer Science,Tsinghua University,Beijing 100084,china 2 Network Research center,Tsinghua University,Beijing 100084,china 3.Tsinghua National Laboratory for Information Science and Technology(TNList) ,Beijing 100084,china 1. Department of Computer Science Tsinghua University Beijing 100084 China 2. Network Research center Tsinghua University Beijing 100084 China 3. Tsinghua National Laboratory for Information Science and Technology (TNList) Beijing 100084 China

Internet has become the most important information infrastructure supporting modern socio-economic development, social progress and technological Innovation. Invented 3. years ago, today Internet is facing increasingly severe technical challenges. This paper introduces the progress of the major international newgeneration Internet research plans; analyzes its basic characteristics and the principal contradictions during the development; detsiledly introduces the research carried out by 973.Project ＂Research of Future Internet Architecture＂ on the key scientific issues of new-generation Internet architecture and its latest research results; and looks to the future of the research-focus faced with the new situations of the basic research of new-generation Internet architecture as well as the new demands of innovative applications on Internet architecture.

关键词： new-generation Internet network architecture multi-dimension scalability

Hydrogen sulfide ameliorates vascular calcification induced by vitamin D3.plus nicotine in rats

在线全文

学校读者我要写书评

暂无评论

Acta Pharmacologica Sinica 2006年第3期27卷 299-306页

作者： Sheng-ying WU~(2,6) Chun-shui PAN~3.Bin GENG~3.Jing ZHAO~3.Fang YU~3.Yong-zheng PANG~3.Chao-shu TANG~4 Yong-fen QI~(3.4,5) ~2Institute of Cardiovascular Disease,Peking University First Hospital.Beijing 10003. ~3.epartment of Physiology and Pathophysiology,Peking University Health Science center,Beijing 100083.china,~4Key Laboratory of Molecular Cardiovascular Science,Ministry of Education,Beijing 100083.china 2Institute of Cardiovascular Disease Peking University First Hospital Beijing 100034 China 3.epartment of Physiology and Pathophysiology Peking University Health Science Center Beijing 100083 China 3.epartment of Physiology and Pathophysiology Peking University Health Science Center Beijing 100083 China 3.epartment of Physiology and Pathophysiology Peking University Health Science Center Beijing 100083 China 3.epartment of Physiology and Pathophysiology Peking University Health Science Center Beijing 100083 China 3.epartment of Physiology and Pathophysiology Peking University Health Science Center Beijing 100083 China 4Key Laboratory of Molecular Cardiovascular Science Ministry of Education Beijing 100083 China 4Key Laboratory of Molecular Cardiovascular Science Ministry of Education Beijing 100083 China

Aim:To investigate the role of the endogenous cystathionine γ-synthase(CSE)/hydrogen sulfide(H2S)pathway in vascular calcification in ***:A ratvascular calcification model was established by administration of vitamin D3.plusnicotine(VDN).The amount of CSE and osteopontin(OPN)mRNA was deter-mined by using semi-quantitative reverse-transcription polymerase chain *** calcium content,45Ca2+accumulation and alkaline phosphatase(ALP)activitywere measured.H,S production and CSE activity were ***:yonKossa staining produced strong positive black/brown staining in areas amongthe elastic fibers of the medial layer in the calcified *** calcium content,45Ca2+accumulation and ALP activity in calcified arteries increased by 6.77-,1.42-,and 1.87-fold,respectively,compared with *** expression of the OPNgene was upregulated(P3..8%,40.75% and 63.5% lowerin the low-dosage NariS group than in the VDN group,respectively(P3.9%,3..8 % and 46.2% lower in the aorta in the high-dosage NariS group than in theVDN group,respectively(P<0.01).The expression of the OPN gene ***:The production of H,S,and CSE activity were de-creased and CSE gene expression was downregulated in rats with vascularcalcification.H2S can ameliorate vascular calcification,suggesting that the H2S/CSE pathway plays a regulatory role in the pathogenesis of vascular calcification.

关键词： hydrogen sulfide cystathionine-lyase vascular calcification mRNA

The biomarkers of 2,6,10,15, 19-pentamethylicosenes and their carbon isotopic composition in the sediments from the Gulf of Mexico

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2006年第14期51卷 1736-1740页

作者： SONG Zhiguang1,2 & WANG Cuiping1,3.. State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, china 2. Guangzhou Research center of Gas Hydrate, Chinese Academy of Sciences, Guangzhou 510640, china 3. Graduate School of Chinese Academy of Sciences, Beijing 10003., china State Key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Guangzhou Research center of Gas Hydrate Chinese Academy of Sciences Guangzhou 510640 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

A group of 2,6,10,15,19-pentamethyli- cosenes (PMIΔ) containing 1―5 unsaturated double bonds has been identified in the sea floor sediments from the Gulf of Mexico at the Green Canyon 23. *** PMIΔ compounds are distributed between nC22 and nC24 on the mass chromatogram of aliphatic fraction. Their δ 13. values are very much depleted in 13. and in the range of ?86.7‰ to ?115.5‰, whereas the δ 13. values of companion n-alkanes range from ?28.4‰ to ?3..6‰. These unsaturated PMIΔ com-pounds are typical biomarkers derived from the an-aerobic oxidation of methane mediated by meth-ane-oxidizing archaeal bacteria and indicative of the gas seeps or even the occurrence of gas hydrates in the deep sea sediments.

关键词：生物标志墨西哥湾沉积物 PMIA 天然气水化物

A formal method to real-time protocol interoperability testing

在线全文

学校读者我要写书评

暂无评论

Science in china(Series F) 2008年第11期51卷 1723-1744页

作者： WANG ZhiLiang1,3.YIN Xia2,3.& JING ChuanMing2,3.1 Network Research center,Tsinghua University,Beijing 100084,china 2 Department of Computer Science and Technology,Tsinghua University,Beijing 100084,china 3.Tsinghua National Laboratory for Information Science and Technology(TNList) ,Beijing 100084,china 1. Network Research center Tsinghua University Beijing 100084 China 3. Tsinghua National Laboratory for Information Science and Technology (TNList) Beijing 100084 China 2. Department of Computer Science and Technology Tsinghua University Beijing 100084 China

Interoperability testing is an important technique to ensure the quality of implementations of network communication protocol. In the next generation Internet protocol, real-time applications should be supported effectively. However, time constraints were not considered in the related studies of protocol interoperability testing, so existing interoperability testing methods are difficult to be applied in real-time protocol interoperability testing. In this paper, a formal method to real-time protocol interoperability testing is proposed. Firstly, a formal model CMpTIOA （communicating multi-port timed input output automata） is defined to specify the system under test （SUT） in real-time protocol interoperability testing; based on this model, timed interoperability relation is then defined. In order to check this relation, a test generation method is presented to generate a parameterized test behavior tree from SUT model; a mechanism of executability pre-determination is also integrated in the test generation method to alleviate state space explosion problem to some extent. The proposed theory and method are then applied in interoperability testing of IPv6 neighbor discovery protocol to show the feasibility of this method.

关键词： protocol testing interoperability testing real-time testing test generation timed input output automata(TIOA)

Strong decays of N~*(153.) in an extended chiral quark model

在线全文

学校读者我要写书评

暂无评论

Science china(Physics,Mechanics & Astronomy) 2009年第10期52卷 1452-1457页

作者： AN ChunSheng1,2,3.& ZOU BingSong1,2,3.1 Institute of High Energy Physics,Chinese Academy of Sciences,Beijing 100049,china 2 Theoretical Physics center for Science Facilities,Chinese Academy of Sciences,Beijing 100049,china 3.Graduate University of Chinese Academy of Sciences,Beijing 100049,china Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Theoretical Physics center for Science Facilities Chinese Academy of Sciences Beijing 100049 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

The strong decays of the N*(153.) resonance are investigated in an extended chiral quark model by including the low-lying $ qqqq\bar q $ components in addition to the qqq component. The results show that these five-quark components in N*(153.) contribute significantly to the N*(153.) → Nπ and N*(153.) → Nη decays. The contributions to the Nη decay come from both the lowest energy and the next-tolowest energy five-quarks components, while the contributions to the Nπ decay come from only the latter one. Taking these contributions into account, the description for the strong decays of N*(153.) is improved, especially for the puzzling large ratio of the decays to Nη and Nπ.

关键词： N*(153.) strong decays five-quark components

2023.Chinese national clinical practice guideline on diagnosis and management of ulcerative colitis

在线全文

学校读者我要写书评

暂无评论

中华医学杂志(英文版) 2024年第14期137卷 1642-1646页

作者： Inflammatory Bowel Disease Group, Chinese Society of Gastroenterology, Chinese Medical Association Inflammatory Bowel Disease Quality Control center of china Inflammatory Bowel Disease Group Chinese Society of Gastroenterology Chinese Medical Association Inflammatory Bowel Disease Quality Control center of china

The role of Chinese expert consensus in standardization and improvement of the clinical diagnosis and treatment of inflammatory bowel disease (IBD) is self-evident. As clinical and basic research in china becomes standardized under a better understanding of IBD, more data on Chinese patients have become available to develop a consensus and guideline. This guideline, collaboratively developed by the IBD Group, Chinese Society of Gastroenterology, incorporates the latest international consensus statements, domestic research findings, and practical considerations, as an update based on the 2018 Chinese consensus on IBD management. The IBD guideline consists of two parts: ulcerative colitis (UC) and Crohn's disease, and this manuscript presented the UC part. The evidence used in this guideline was collected and analyzed by the standard of guideline, and the contents were organized as problem statements, for clarity. The formulation of this guideline aimed to reflect the latest progress in IBD, providing comprehensive and valuable guidance for the clinical management of IBD.

关键词：

同方期刊数据库

Carbon isotope ratios of C_(4) plants in loess areas of North china

在线全文

学校读者我要写书评

暂无评论

Science china Earth Sciences 2006年第1期49卷 97-102页

作者： WANG Guoan1,2,3. HAN Jiamao 2, ZHOU Liping3. XIONG Xiaogang4, TAN Ming2, WU Zhenhai5 & PENG Jun6 1. Department of Plant Nutrition, china Agricultural University, Beijing 100094, china 2. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, china 3. College of Environmental Sciences, MOE Laboratory for Earth Surface Processes, Peking University, Beijing 100871, china 4. Institute of Botany, Chinese Academy of Sciences, Beijing 100093. china 5. Northwest Sci-Tech University of Agriculture and Forestry, Yangling 712100, china 6. Network center, china Agricultural University, Beijing 100094, china 1. Department of Plant Nutrition China Agricultural University Beijing 100094 China 2. Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 3. College of Environmental Sciences MOE Laboratory for Earth Surface Processes Peking University Beijing 100871 China 4. Institute of Botany Chinese Academy of Sciences Beijing 100093 China 5. Northwest Sci-Tech University of Agriculture and Forestry Yangling 712100 China 6. Network center China Agricultural University Beijing 100094 China

Carbon isotope ratios (δ^(13.C) of 89 C_4 plant samples were determined fromthe loess area in North china. δ^(13.C values vary between -10.5per thousand and -14.6per thousandwith a mean of -12.6per thousand. Along a precipitation gradient from the semi-moist area to thesemiarid area, then to the arid area, the δ^(13.C values of C_4 plants show a slight decreasingtrend. The δ^(13.C values of C_4 plants in the dry season are found lower than those in the wetseason. These trends are opposite to those observed for C_3.species.

关键词： C4 plants, carbon isotope ratios, loess area.

A novel method for evaluating and improving the 1H-MRSI glioma data quality

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2005年第8期15卷 765-768页

作者： YUAN Kehong 1,2, LU Hongyu2, BAO Shanglian2*, CHEN Qiansheng1, LI Shaowu3.and DUAN Chaijie2(1. Key Laboratory of Pure and Applied Mathematics, School of Mathematical Sciences, Beijing 100871, china 2. The Research center for Tumor Diagnosis and Therapeutical Physics & the Beijing Key Laboratory of Medical Physics and Engineering, Peking University, Beijing 100871, china 3. The Tian Tan Hospital, Beijing 100050, china) Key Laboratory of Pure and Applied Mathematics School of Mathematical Sciences Beijing 100871 China. The Research center for Tumor Diagnosis and Therapeutical Physics & the Beijing Key Laboratory of Medical Physics and Engineering Peking University Beijing 100871 China. The Tian Tan Hospital Beijing 100050 China

Metabolic information obtained by proton magnetic resonance spectroscopic imaging (1H-MRSI) has been approved to be a powerful tool to identify either benign or malignant glioma, as well as to confirm the tumor level. However, 1H-MRSI data are affected by various factors, such as the thermal noise, eddy currents, susceptibility artifacts, and rigid body motion. To get accurate quantitative metabolic information, the key problem is to assess the 1H-MRSI data quality. In this paper, we introduce a new evaluating system to filter the data, and a new method, called wavelet denoising method, to improve the data quality under the evaluating system. Experimental results on 1H-MRSI glioma data demonstrate that preprocessing is prerequisite and the proposed algorithm with evaluating system is effective.

关键词： 1H-MRSI evaluating system glioma data quality wavelet denoising

Expression of PDCD5 , a novel apoptosis related protein, in human osteoarthritic cartilage

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Acta Pharmacologica Sinica 2004年第05期25卷 143-148页

作者： Ai-xin CHENG, Si-quan LOU2, Hao-wei ZHOU, Ying WANG3. Da-long MA3.epartment of Orthopaedic Surgery, Third Hospital, Peking University, Beijing 100083.3.0} for Human Disease Genomics, Peking University, Beijing 100083. china Department of Orthopaedic Surgery Third Hospital Peking University center for Human Disease Genomics Peking University

AIM: To investigate the expression features of PDCD5 (programmed cell death 5 protein) in osteoarthritic andnormal human cartilage, and speculate on its potential functions in the pathogenesis of osteoarthritis (OA).METHODS: Articular cartilage specimens were obtained from 3. patients with OA and 16 healthy patients at thetime of arthroplasty. Expression of PDCD5 was detected by flow cytometry, immunofluorescence, RT-PCR andimmunohistochemical analysis. RESULTS: Enhanced expression and nuclear accumulation of PDCD5 in OAchondrocytes were found. PDCD5-positive chondrocytes were mainly distributed in the superficial and deep zonesof OA tissue sections, as opposed to, in the superficial and middle regions of normal healthy tissue ***: Since apoptotic chondrocyte death occurs more frequently in OA cartilage than in normal healthycartilage and PDCD5 is an apoptosis-related protein, the different expression patterns of PDCD5 in OA cartilagefrom that in normal healthy cartilage indicate that PDCD5 is involved in the pathogenesis of OA.

关键词： apoptosis cartilage osteoarthritis PDCD5