检索结果-南通市图书馆

World Journal of Gastroenterology 2009年第17期15卷 2151-2155页

作者： shi-hua ding jun liu jian-ping wang Department of Gastroenterology The Affiliated Shenzhen Hospital Nanfang Medical University Shenzhen 518035 Guangdong Province China

AIM: To systematically assess the efficacy and safety of β-adrenergic blocker plus 5-isosorbide mononitrate (BB + ISMN) and endoscopic band ligation (EBL) on prophylaxis of esophageal variceal rebleeding. METHODS: Randomized controlled trials (RCTs) comparing the efficacy and safety of BB + ISMN and EBL on prophylaxis of esophageal variceal rebleeding were gathered from Medline, Embase, Cochrane Controlled Trial Registry and China Biological Medicine database between January 1980 and August 2007. Data from five trials were extracted and pooled. The analyses of the available data using the Revman 4.2 software were based on the intention-to-treat principle. RESULTS: Four RCTs met the inclusion criteria. In comparison with BB + ISMN with EBL in prophylaxis of esophageal variceal rebleeding, there was no significant difference in the rate of rebleeding [relative risk (RR), 0.79; 95% CI: 0.62-1.00; P = 0.05], bleeding-related mortality (RR, 0.76; 95% CI: 0.31-1.42; P = 0.40), overall mortality (RR, 0.81; 95% CI: 0.61-1.08; P = 0.15) and complications (RR, 1.26; 95% CI: 0.93-1.70; P = 0.13). CONCLUSION:In the prevention of esophageal variceal rebleeding, BB + ISMN are as effective as EBL. There are few complications with the two treatment modalities. Both BB + ISMN and EBL would be considered as the first-line therapy in the prevention of esophageal variceal rebleeding.

关键词： Meta-analysis Esophageal variceal rebleeding Endoscopic band ligation β-adrenergicblocker 5-isosorbide mononitrate Prophylaxis

Convolution-based multi-scale envelope inversion

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Petroleum Science 2020年第2期17卷 352-362页

作者： ding-Jin liu jian-ping huang Zi-Ying wang Sinopec Geophysical Research Institute Nanjing 211103JiangsuChina China University of Petroleum(East China) Qingdao 266580ShandongChina Pilot National Laboratory for Marine Science and Technology Qingdao 266571ShandongChina

Envelope inversion(El)is an efficient tool to mitigate the nonlinearity of conventional full waveform inversion(FWI)by utilizing the ultralow-frequency component in the seismic ***,the performance of envelope inversion depends on the frequency component and initial model to some *** improve the convergence ability and avoid the local minima issue,we propose a convolution-based envelope inversion method to update the low-wavenumber component of the velocity ***,the multi-scale inversion strategy(MCEI)is also incorporated to improve the inversion accuracy while guaranteeing the global *** success of this method relies on modifying the original envelope data to expand the overlap region between observed and modeled envelope data,which in turn expands the global minimum basin of misfit *** accurate low-wavenumber component of the velocity model provided by MCEI can be used as the migration model or an initial model for conventional *** numerical tests on simple layer model and complex BP 2004 model verify that the proposed method is more robust than El even when the initial model is coarse and the frequency component of data is high.

关键词： Full waveform inversion Multi-scale strategy Envelope inversion

Approximation Algorithms for Solving the 1-Line Minimum Steiner Tree of Line Segments Problem

在线全文

学校读者我要写书评

暂无评论

Journal of the Operations Research Society of China 2024年第3期12卷 729-755页

作者： jian-ping Li Su-ding liu jun-Ran Lichen Peng-Xiang Pan Wen-Cheng wang Department of Mathematics Yunnan UniversityKunming650504YunnanChina School of Mathematics and Physics Beijing University of Chemical TechnologyBeijing650504China

We address the 1-line minimum Steiner tree of line segments(1L-MStT-LS)***,given a set S of n disjoint line segments in R^(2),we are asked to find the location of a line l and a set E_(l) of necessary line segments(i.e.,edges)such that a graph consisting of all line segments in S ∪ E_(l) plus this line l,denoted by T_(l)=(S,l,E_(l)),becomes a Steiner tree,the objective is to minimize total length of edges in E_(l) among all such Steiner ***,we are asked to find a set E_(0) of necessary edges such that a graph consisting of all line segments in S ∪ E_(0),denoted by T_(S)=(S,E_(0)),becomes a Steiner tree,the objective is to minimize total length of edges in E_(0) among all such Steiner trees,we refer to this new problem as the minimum Steiner tree of line segments(MStT-LS)*** addition,when two endpoints of each edge in Eo need to be located on two different line segments in S,respectively,we refer to that problem as the minimum spanning tree of line segments(MST-LS)*** obtain three main results:(1)Using technique of Voronoi diagram of line segments,we design an exact algorithm in time O(n log n)to solve the MST-LS problem;(2)we show that the algorithm designed in(1)is a 1.214-approximation algorithm to solve the MStT-LS problem;(3)using the combination of the algorithm designed in(1)as a subroutine for many times,a technique of finding linear facility location and a key lemma proved by techniques of computational geometry,we present a 1.214-approximation algorithm in time O(n^(3) log n)to solve the 1L-MStT-LS problem.

关键词： 1-Line minimum Steiner tree of line segments Minimum spanning tree of line segments Voronoi diagram of line segments Steiner ratio Approximation algorithms

Associations between low-density lipoprotein cholesterol and haemorrhagic stroke

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Geriatric Cardiology 2021年第3期18卷 204-209页

作者： Yun-Yan XIE shi-Meng liu Qian ZHANG Yu JIA jian-ping ding Department of Neurology Xuanwu HospitalCapital Medical UniversityBeijingChina Department of Neurology University of CaliforniaIrvineIrvineCaliforniaUSA Department of Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijingChina

OBJECTIVE To investigate the associations between the blood concentrations of low-density lipoprotein cholesterol(LDL-C)and the clinical features of haemorrhagic *** This study analysed the data from patients with acute haemorrhagic stroke at a comprehensive stroke centre from 2013 to *** were stratified into three groups according to their baseline LDL-C levels:2)at *** Six-hundred and six patients were *** median age was 58 *** the patients,75(12%)patients had LDL-C levels<70 mg/dL,194(32%)patients had LDL-C levels between 70 to<100 mg/dL and the other 337(56%)patients had LDL-C levels≥100 mg/*** with higher LDL-C levels were less likely to suffer severe neurological deficits(LDL-C:70 to<100 vs.<70 mg/dL,adjusted odds ratio[OR]:0.29,95%CI:0.15–0.57;LDL-C:≥100 vs.<70 mg/dL,adjusted OR=0.27,95%CI:0.15–0.51)and to have unfavourable outcomes at discharge(LDL-C:70 to<100 vs.<70 mg/dL,adjusted OR=0.50,95%CI:0.29–0.87 and LDL-C:≥100 vs.<70 mg/dL,adjusted OR=0.46,95%CI:0.28–0.78).CONCLUSIONS An LDL-C level<70 mg/dL was independently associated with severe neurological deficits of haemorrhagic stroke and may increase the risks of unfavourable outcomes at discharge.

关键词： haemorrhagic lipoprotein cholesterol

Identification of hydrovolcanism and its significance for hydrocarbon reservoir assessment: A review

在线全文

学校读者我要写书评

暂无评论

Journal of Palaeogeography 2018年第4期7卷 346-362页

作者： Ben-Zhong Xian Yan-Xin He hua-Peng Niu jun-Hui wang jian-ping liu Zhen wang College of Geosciences China University of Petroleum (Beijing) State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum (Beijing)

Investigations of modern volcanic eruptions have demonstrated that ancient volcanic eruptions widely involved water,which was thus named as hydrovolcanic eruptions. Hydrovolcanisms are distinctive in many aspects, such as dynamics,eruptive pattern, texture and structure of rock, and vesicularity. First, normal sediments covered directly by volcanic rocks are the indicators of eruption environments. In addition, microfeatures, special structures, lithofacies or facies associations,and geochemical index of volcanic rocks can also provide significant evidences. Moreover, perlitic texture, quenching fragmentation, surface feature, cementation type, vesicularity, and pillow structure, parallel bedding, large-scale low-angle cross-bedding, antidune cross-bedding of pyroclast are keys to indicating hydrovolcanisms. Clearly,these marks are not equally reliable for identifying eruption environments, and most of them are effective and convincible in limited applications only. For explosive eruptions, the most dependable identification marks include quenching textures, vesicularity in pyroclasts and special large-scale cross-bedding. However, for effusive eruptions,useful indicators mainly include pillow structure, peperite and facies associations. Condensation rate of magma,exsolution of volatile affected by eruptive settings and magma—water interaction, and quenching in hydrovolcanisms have an influence on formation and scale of primary pores, fractures and their evolution during diagenetic ***, this review provides systematic identification marks for ancient hydrovolcanisms, and promotes understanding of the influence of eruptive environments on hydrocarbon reservoirs of volcanic rocks in oil-gas bearing sedimentary basins.

关键词： Hydrovolcanism Volcanic reservoir Eruption environment Hydrocarbon reservoir Oilgas bearing sedimentary basin

Vulnerability of mountain glaciers in China to climate change

在线全文

学校读者我要写书评

暂无评论

Advances in Climate Change Research 2015年第3期6卷 171-180页

作者： YANG jian-ping ding Yong-jian liu shi-Yin TAN Chun-ping State Key Laboratory of Cryospheric Sciences Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Key Laboratory of Eco-hydrology of Inland River Basin Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences

Mountain glaciers in China are an important water source for both China and adjoining countries, and therefore their adaptation to glacier change is crucial in relation to maintaining populations. This study aims to improve our understanding of glacial vulnerability to climate change to establish adaptation strategies. A glacial numerical model is developed using spatial principle component analysis （SPCA） supported by remote sensing （RS） and geographical information system （GIS） technologies. The model contains nine factors--slope, aspect, hillshade, elevation a.s.l., air temperature, precipitation, glacial area change percentage, glacial type and glacial area, describing topography, climate, and glacier characteristics. The vulnerability of glaciers to climate change is evaluated during the period of 1961-2007 on a regional scale, and in the 2030s and 2050s based on projections of air temperature and precipitation changes under the IPCC RCP6.0 scenario and of glacier change in the 21st century. Glacial vulnerability is graded into five levels： potential, light, medial, heavy, and very heavy, using natural breaks classification （NBC）. The spatial distribution of glacial vulnerability and its temporal changes in the 21st century for the RCP6.0 scenario are analyzed, and the factors influencing vulnerability are discussed. Results show that mountain glaciers in China are very vulnerable to climate change, and 41.2% of glacial areas fall into the levels of heavy and very heavy vulnerability in the period 1961-2007. This is mainly explained by topographical exposure and the high sensitivity of glaciers to climate change. Trends of glacial vulnerability are projected to decline in the 2030s and 2050s, but a declining trend is still high in some regions. In addition to topographical factors, variation in precipitation in the 2030s and 2050s is found to be crucial.

关键词： Mountain glaciers Climate change Vulnerability Projection

visual bone marrow mesenchymal stem cell transplantation in the repair of spinal cord injury

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2015年第3期10卷 404-411页

作者： Rui-ping Zhang Cheng Xu Yin liu jian-ding Li jun Xie Department of Radiology First HospitalShanxi Medical University Molecular Imaging Program at Stanford Stanford University Department of Radiology Shanxi Provincial People’s Hospital Department of Molecular Biology Shanxi Medical University

An important factor in improving functional recovery from spinal cord injury using stem cells is maximizing the number of transplanted cells at the lesion site. Here, we established a contusion model of spinal cord injury by dropping a weight onto the spinal cord at T7_8. Superparamagnet- ic iron oxide-labeled bone marrow mesenchymal stem cells were transplanted into the injured spinal cord via the subarachnoid space. An outer magnetic field was used to successfully guide the labeled cells to the lesion site. Prussian blue staining showed that more bone marrow mesen- chymal stem cells reached the lesion site in these rats than in those without magnetic guidance or snperparamagnetic iron oxide labeling, and immunofluorescence revealed a greater number of complete axons at the lesion site. Moreover, the Basso, Beattie and Bresnahan （BBB） locomotor rating scale scores were the highest in rats with superparamagnetic labeling and magnetic guid- ance. Our data confirm that superparamagnetic iron oxide nanoparticles effectively label bone marrow mesenchymal stem cells and impart sufficient magnetism to respond to the external magnetic field guides. More importantly, superparamagnetic iron oxide-labeled bone marrow mesenchymal stem cells can be dynamically and non-invasively tracked in vivo using magnetic resonance imaging. Superparamagnetic iron oxide labeling of bone marrow mesenchymal stem cells coupled with magnetic guidance offers a promising avenue for the clinical treatment of spinal cord injury.

关键词： nerve regeneration superparamagnetic iron oxide magnetic guidance bone marrowmesenchymal stem cells spinal cord injury cell transplantation magnetic resonance image lumbarpuncture neural regeneration

The prevalence of azoospermia factor microdeletion on the Y chromosome of Chinese infertile men detected by multi-analyte suspension array technology

在线全文

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2008年第6期10卷 873-881页

作者： Yi-jian Zhu Si-Yao liu huan wang ping Wei Xian-ping ding Institute of Medical Genetics Key Laboratory of Bio-resources and Eco-environment Ministry of Education College of Life Science Sichuan University Chengdu 610064 China

Aim： To develop a high-throughput multiplex, fast and simple assay to scan azoospermia factor （AZF） region microdeletions on the Y chromosome and establish the prevalence of Y chromosomal microdeletions in Chinese infertile males with azoospermia or oligozoospermia. Methods： In total, 178 infertile patients with azoospermia （nonobstructed）, 134 infertile patients with oligozoospermia as well as 40 fertile man controls were included in the present study. The samples were screened for AZF microdeletion using optimized multi-analyte suspension array （MASA） technology. Results： Of the 312 patients, 36 （11.5%） were found to have deletions in the AZF region. The rnicrodeletion frequency was 14% （25/178） in the azoospermia group and 8.2% （11/134） in the oligospermia group. Among 36 patients with microdeletions, 19 had deletions in the AZFc region, seven had deletions in AZFa and six had deletions in AZFb. In addition, four patients had both AZFb and AZFc deletions. No deletion in the AZF region was found in the 40 fertile controls. Conclusion： There is a high prevalence of Y chromosomal microdeletions in Chinese infertile males with azoospermia or oligozoospermia. The MASA technology, which has been established in the present study, provides a sensitive and high-throughput method for detecting the deletion of the Y chromosome. And the results suggest that genetic screening should be advised to infertile men before starting assisted reproductive treatments.

关键词： Y chromosome microdeletion azoospermia factor male infertility multi-analyte suspension array (MASA)

Molecular regulation of telomerase activity in aging

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Protein & Cell 2011年第9期2卷 726-738页

作者： Craig Nicholls He Li jian-Qiu wang jun-ping liu Molecular Signalling Laboratory Murdoch Childrens Research InstituteFlemington RoadParkvilleVictoria 3052Australia Institute of Aging Research Hangzhou Normal University School of MedicineHangzhou 310036China Department of Immunology Monash UniversityMelbourneVictoria 3004Australia Department of Genetics University of MelbourneVictoria 3052Australia

The process of aging is mitigated by the maintenance and repair of chromosome ends(telomeres),resulting in extended *** review examines the molecular mechanisms underlying the actions and regulation of the enzyme telomerase reverse transcriptase(TERT),which functions as the primary mechanism of telomere maintenance and regulates cellular life *** increased cell proliferation,telomerase is also a key factor in facilitating cancer cell *** review focuses on aspects of hormonal regulations of telomerase,and the intracellular pathways that converge to regulate telomerase activity with an emphasis on molecular interactions at protein and gene *** addition,the basic structure and function of two key telomerase enzyme components—the catalytic subunit TERTand the template RNA(TERC)are discussed briefly.

关键词： telomerase aging telomerase reverse transcriptase(TERT)

Neoadjuvant chemotherapy for locally advanced cervical cancer reduces surgical risks and lymph-vascular space involvement

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Cancer 2011年第9期30卷 645-654页

作者： Yue wang Guang wang Li-Hui Wei Ling-Hui huang jian-liu wang shi-jun wang Xiao-ping Li Dan-hua Shen Dong-Mei Bao jian Gao Department of Obstetrics ＆ Gynecology People＇s Hospital Peking University Beijing 100044 P. R. China Department of Obstetrics ＆ Gynecology Hangu Hospital Tianjin 300480 P. R. China Department of Obstetrics ＆ Gynecology Jinghong Municipal Hospital Jinghong Yunnan 666100 P. R. China Department of Pathology People＇s Hospital Peking University Beijing 100044 P. R. China Department of Radiology People＇s Hospital Peking University Beijing 100044. p. R. China.

Neoadjuvant chemotherapy(NACT),which can reduce the size and therefore increase the resectability of tumors,has recently evolved as a treatment for locally advanced cervical *** has been reported to decrease the risk of pathologic factors related to prognosis of cervical *** further assess the effects of NACT on surgery and the pathologic characteristics of cervical cancer,we reviewed 110 cases of locally advanced cervical cancer treated with radical hysterectomy with or without NACT at the People's Hospital of Peking University between January 2006 and December *** 110 patients,68 underwent platinum-based NACT prior to surgery(NACT group) and 42 underwent primary surgery treatment(PST group).Our results showed 48 of 68(70.6%) patients achieved a complete response or partial response to *** blood loss,operation time,and number of removed lymph nodes during surgery,as well as complication rates during and after surgery were not significantly different between the NACT group and the PST *** rates of deep stromal invasion,positive parametria,positive surgical vaginal margins,and lymph node metastasis were not significantly different between the two ***,the rate of lymph-vascular space involvement(LVSI) was significantly lower in the NACT group than in the PST group(P = 0.021).In addition,the response rate of NACT was significantly higher in the patients with chemotherapeutic drugs administrated via artery than via *** results suggest that NACT is a safe and effective treatment for locally advanced cervical cancer and significantly decreases the rate of LVSI.

关键词：手术治疗子宫颈癌化疗药物淋巴结晚期间隙血管风险