检索结果-南通市图书馆

Pathogenesis of acute lung injury in rats with severe acute pancreatitis

在线全文

学校读者我要写书评

暂无评论

Hepatobiliary & Pancreatic Diseases International 2005年第4期4卷 614-617页

作者： Xue-Min Liu, Jun Xu and zi-fa wang Department of Hepatobiliary Surgery, First Hospital, Xi’an Jiaotong University, Xi’an 710061 , China Department of Hepatobiliary Surgery First Hospital Xi'an Jiaotong University Xi'an 710061 China. a1090224@***

BACKGROUND: Acute lung injury (ALI) is the most common and severe complication of severe acute pancreatitis (SAP). The elucidation of the mechanism of ALI contributes to the diagnosis and treatment of the illness. In this study, we studied the pathogenesis of ALI in rats with severe acute pancreatitis. METHODS: The rats were sacrificed at 1, 3, 5, 6, 9 and 12 hours after the establishment of the model of SAP. Pancreas and lung tissues were obtained for pathological study, and examination of microvascular permeability and myeloperoxidase (MPO) examination. The gene expressions of tumor necrosis factor-α (TNF-α) and intercellular adhesion molecule-1 (ICAM-1) in the pancreas and lung tissues were detected by reverse transcriptase-polymerase chain reaction (RT-PCR). RESULTS: After the establishment of the SAP model, the degree of pancreatic and lung injury increased gradually along with the gradual increase of MPO activity and micro-vascular permeability. Gene expressions of TNF-α and ICAM-1 in the pancreas rose at 1 hour and peaked at 7 hours. In contrast, their gene expression in the lungs rose slightly at 1 hour and peaked at 9-12 hours. CONCLUSION: An obvious time window existed between SAP and lung injury, which is beneficial to the early prevention of the development of ALI.

关键词： pathogenesis severe acute pancreatitis acute lung injury

The role of inflammatory mediators in severe acute pancreatitis and regulation of glucocorticoids

在线全文

学校读者我要写书评

暂无评论

Hepatobiliary & Pancreatic Diseases International 2003年第3期2卷 458-462页

作者： zi-fa wang Cheng-En Pan Yi Lu Shao-Gao Liu Guan-Jun Zhang Xue-Bin Zhang the Departments of Surgery and Pathology First Hospital, Xi’an Jiaotong University, Xi’an 710061, China the Department of Surgery, University of Pittsburgh, NW607, Montefiore University Hospital, 3459 Fifth Avenue, Pittsburgh, PA 15213, USA Department of Surgery University of Pittsburgh NW607 Montefiore University Hospital 3459 Fifth Avenue Pittsburgh PA 15213 USA. ziw3@pitt.edu

OBJECTIVE: To investigate the effect of glucocorticoids on systemic inflammatory mediator release in rats with acute pancreatitis and the outcome of dexamethasone in treatment of acute pancreatitis. METHODS: Sixty-eight Wistar rats were divided into sham, acute pancreatitis, and treatment (intravenous dexamethasone 0.5 mg/kg) groups. Experimental acute pancreatitis was induced by the injection of 5% sodium taurocholate (0.1 ml/100 mg body weight) into the pancreatic-biliary duct. The bIood samples were obtained and examined for 6-keto-PGI_1α, TXB_2 and IL-6 postoperatively at 3,6 and 12 hours, respectively. The pancreatic samples were evaluated by a blinded method. Twelve-hour survival rate was determined and compared between the groups. RESULTS: The high serum concentrations of 6-keto-PGI_1α, TXB_2 and IL-6 were noted in the rats with acute pancreatitis associated with pancreatic hemorrhage and necrosis. Their 12-hour survival rate was 42.9%. The rats in the treatment group survived with significantly reduced serum concentrations of 6-keto-PGI_1α, TXB_2 and IL-6 (P<0.05). Their pancreatic morphology was normal. CONCLUSION: Dexamethasone may reduce the serum concentration of 6-keto-PGI_1α, TXB_2, and IL-6, and the severity of acute pancreatitis while increasing the survival rate of rats with acute pancreatitis.

关键词： acute pancreatitis inflammatory mediators dexamethasone

Liver retransplantation: indications and outcomes

在线全文

学校读者我要写书评

暂无评论

Hepatobiliary & Pancreatic Diseases International 2004年第2期3卷 175-178页

作者： zi-fa wang and Chang Liu Pittsburgh, USA Department ot Surgery, University of Pittsburgh Me- dical Center, Pittsburgh, PA 15213, USA Division of Hepa- tobiliary Surgery . First Hospital, Xi’ an Jiaotong University , Xi’ an 710061, China Department of Surgery University of Pittsburgh NW607 Montefiore University Hospital 3459 Fifth Avenue Pittsburgh PA 15213 USA. ziw3@pitt.edu

BACKGROUND: Liver transplantation is a life-saving the- rapeutic modality for patients with end-stage liver diseases. After liver transplantation, however, more than 10% pa- tients may lose the grafts caused by a variety of reasons. This review covers the most frequent indications for liver retransplantation as well as the results and specific problems with each indication. DATA RESOURCES: Searching MEDLINE (1997-2003) for articles on liver retransplantation. RESULTS: The most frequent indications of liver retrans- plantation are primary non-function, hepatic artery throm- bosis, graft rejection and recurrent diseases. The results af- ter liver retransplantation remain inferior to those after first transplantation. CONCLUSION: Liver retransplantation, which is the only means of prolonging survival in those patients whose initial graft has failed, makes an important contribution to overall survival.

关键词： liver retransplantation primary non-function hepatic artery thrombosis rejection recurrent diseases

Constraining Dark Energy and Cosmological Transition Redshift with Type Ia Supernovae

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Astronomy and Astrophysics 2006年第5期6卷 561-571页

作者： fa-Yin wang zi-Gao Dai Department of Astronomy Nanjing University Nanjing 210093

The property of dark energy and the physical reason for the acceleration of the present universe are two of the most difficult problems in modern cosmology. The dark energy contributes about two-thirds of the critical density of the present universe from the observations of type-Ia supernovae （SNe Ia） and anisotropy of cosmic microwave background （CMB）. The SN Ia observations also suggest that the universe expanded from a deceleration to an acceleration phase at some redshift, implying the existence of a nearly uniform component of dark energy with negative pressure. We use the ＂Gold＂ sample containing 157 SNe Ia and two recent well-measured additions, SNe Ia 1994ae and 1998aq to explore the properties of dark energy and the transition redshift. For a fiat universe with the cosmological constant, we measure ΩM=0.28-0.05^＋0.04 which is consistent with Riess et al. The transition redshift is zT=0.60-0.08^＋0.04. We also discuss several dark energy models that define w（z） of the parameterized equation of state of dark energy including one parameter and two parameters （w（z） being the ratio of the pressure to energy density）. Our calculations show that the accurately calculated transition redshift varies from zT =0.29-0.06^＋0.07 to zT =0.60-0.08^＋0.06 across these models. We also calculate the minimum redshift zc at which the current observations need the universe to accelerate.

关键词： cosmology observations -- distance scale -- supernovae general

Constraints on generalized Chaplygin gas model including gamma-ray bursts

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Astronomy and Astrophysics 2009年第5期9卷 547-557页

作者： fa-Yin wang zi-Gao Dai Shi Qi Department of Astronomy Nanjing University Nanjing 210093 China Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China Joint Center for Particle Nuclear Physics and Cosmology Nanjing University- Purple Mountain Observatory Nanjing 210093 China

Generalized Chaplygin gas （whose equation of state is PGCG = -A/ρGCG^α） was proposed as a candidate for unification of dark energy and dark matter. We investigate constraints on this model with the latest observed data. We test the model with type-Ia supernovae （SNe Ia）, cosmic microwave background （CMB） anisotropy, X-ray gas mass fractions in clusters, and gamma-ray bursts （GRBs）. We calibrate the GRB luminosity relations without assuming any cosmological models using SNe Ia. We show that GRBs can extend the Hubble diagram to higher redshifts （z 〉 6）. The GRB Hubble diagram is well behaved and delineates the shape of the Hubble diagram well. We measure As≡A/ρGCG,0^α＋1 =0.68-0.08^＋0.04（where PGCG,0 is the energy density today） and α=-0.22 -0.13^＋0.15 at the 1σ confidence level using all the datasets. Our results rule out the standard Chaplygin gas model （α = 1） at the 3σ confidence level. The ACDM is allowed at the 2σ confidence level. We find that acceleration could have started at a redshift of z - 0.70. The concordance of the generalized Chaplygin gas model with the age estimate of an old high redshift quasar is found. In addition, we show that GRBs can break the degeneracy between the generalized Chaplygin gas model and the XCDM model.

关键词： gamma-rays bursts -- cosmology theory

What makes the Tc of monolayer FeSe on SrTiO3 so high： a sign-problem-free quantum Monte Carlo study

在线全文

学校读者我要写书评

暂无评论

Science Bulletin 2016年第12期61卷 925-930页

作者： zi-Xiang Li fa wang Hong Yao Dung-Hai Lee Institute for Advanced Study Tsinghua UniversityBeijing 100084China International Center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China Collaborative Innovation Center of Quantum Matter Beijing 100871China Department of Physics University of CaliforniaBerkeleyCA 94720USA Materials Sciences Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA

Monolayer FeSe films grown on SrTiO_3(STO)substrate show superconducting gap-opening temperatures(T_c) which are almost an order of magnitude higher than those of the bulk FeSe and are highest among all known Fe-based superconductors. Angle-resolved photoemission spectroscopy observed ‘‘replica bands' ' suggesting the importance of the interaction between FeSe electrons and STO phonons. These facts rejuvenated the quest for T_c enhancement mechanisms in iron-based, especially ironchalcogenide, superconductors. Here, we perform the first numerically-exact sign-problem-free quantum Monte Carlo simulations to iron-based superconductors. We(1) study the electronic pairing mechanism intrinsic to heavily electron doped FeSe films, and(2) examine the effects of electron–phonon interaction between FeSe and STO as well as nematic fluctuations on T_c. Armed with these results, we return to the question ‘‘what makes the Tcof monolayer FeSe on SrTiO_3 so high?'' in the conclusion and discussions.

关键词： High temperature superconductivity Pairing mechanism Iron-based superconductivity FeSe/STO Sign-problem-free quantum Monte-Carlosimulation

Coupling characteristics between five-layer slab wave-guides including left-handed materials

在线全文

学校读者我要写书评

暂无评论

Optoelectronics Letters 2008年第6期4卷 419-421页

作者： SHEN Lu- fa wang zi-hua Science College Huzhou Normal University Huzhou 313000 China School of Communication and lnformation Engineering Shanghai University Shanghai 200072 China

To obtain the coupling characteristics between slab wave-guides including left-handed material,we modify the coupled wave equations by using Maxwell’s equations. First,we obtain new-coupled wave equations and new-coupling coefficient. Second,the coupling between two identical five-layer slab wave-guides where their cores are left-handed material,but their claddings are right-handed materials is studied. The coupling coefficient for even TE mode which is more complex than that of the riglt-handed material slab wave guides,is obtained.

关键词：五层组合板波导光学应用左手材料

Discrete vortices on anisotropic lattices

在线全文

学校读者我要写书评

暂无评论

Frontiers of physics 2015年第4期10卷 55-60页

作者： Gui-Hua Chen Hong-Cheng wang zi-fa Chen Department of Electronic Engineering Dongguan University of Technology Dongguan 523808 China

We consider the effects of anisotropy on two types of localized states with topological charges equal to 1 in two-dimensional nonlinear lattices, nsing the discrete nonlinear SchrSdinger equation as a paradigm model. We find that on-site-centered vortices with different propagation constants are not globally stable, and that upper and lower boundaries of the propagation constant exist. The region between these two boundaries is the domain outside of which the on-site-centered vortices are unstable. This region decreases in size as the anisotropy parameter is gradually increased. We also consider off-site-centered vortices on anisotropic lattices, which are unstable on this lattice type and either transform into stable quadrupoles or collapse. We find that the transformation of off-site- centered vortices into quadrupoles, which occurs on anisotropic lattices, cannot occur on isotropic lattices. In the quadrupole case, a propagation-constant region also exists, outside of which the localized states cannot stably exist. The influence of anisotropy on this region is almost identical to its effects on the on-site-centered vortex case.

关键词： anisotropy discrete vortex quadrupole localized state

Forecast of cosmological constraints with superluminous supernovae from the Chinese Space Station Telescope

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 128-138页

作者： Xuan-Dong Jia Jian-Ping Hu fa-Yin wang zi-Gao Dai School of Astronomy and Space Science Nanjing UniversityNanjing 210093China Key Laboratory of Modern Astronomy and Astrophysics(Nanjing University) Ministry of EducationNanjing 210093China Department of Astronomy University of Science and Technology of ChinaHefei 230026China

Superluminous supernovae(SLSNe)are a class of intense celestial events that can be standardized for measuring cosmological parameters,bridging the gap between type Ia supernovae and the cosmic microwave *** this work,we discuss the cosmological applications of SLSNe from the Chinese Space Station Telescope(CSST).Our estimation suggests that SLSNe rate is biased tracing the cosmic star formation rate,exhibiting a factor of(1+z)^(1.2).We futher predict that CSST is poised to observe~360 SLSNe in the 10 square degrees ultra-deep field survey within a span of 2.5 years.A stringent constraint on cosmological parameters can be derived from their peak-color *** is anticipated to uncover a substantial number of SLSNe,contributing to a deeper understanding of their central engines and shedding light on the nature of dark energy at high redshifts.

关键词： supernovae cosmology cosmological constant