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国际医学放射学杂志 2024年第4期 498-498页

作者： c.Bilreiro L.andrade R.M.marques c.Matos 胡佳圆

摘要目的探讨扩散加权成像（DWI）在预测胰腺癌新辅助治疗（NAT）反应中的作用。方法检索MEDLINE、EMBASE和cochrane图书馆数据库，寻找有关表观扩散系数

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Artificial root exudates and soil organic carbon mineralization in a degraded sandy grassland in northern china

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Journal of Arid Land 2014年第4期6卷 423-431页

作者： YongQing LUO XueYong ZHAO Olof andréN Yangchun ZHU WenDa HUANG Naiman Desertification and Farmland Research Station of the cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences University of chinese Academy of Sciences Bjorklundavagen 3

Plant root exudates contain various organic and inorganic components that include glucose, citric and oxalic acid. These components affect rhizosphere microbial and microfaunal activities, but the mechanisms are not fully known. Studies concerned from degraded grassland ecosystems with low soil carbon（c） contents are rare, in spite of the global distribution of grasslands in need of restoration. All these have a high potential for carbon sequestration, with a reduced carbon content due to overutilization. An exudate component that rapidly decomposes will increase soil respiration and cO2 emission, while a component that reduces decomposition of native soil carbon can reduce cO2 emission and actually help sequestering carbon in soil. Therefore, to investigate root exudate effects on rhizosphere activity, citric acid, glucose and oxalic acid（0.6 g c/kg dry soil） were added to soils from three biotopes（grassland, fixed dune and mobile dune） located in Naiman, Horqin Sandy Land, Inner Mongolia, china） and subjected to a 24-day incubation experiment together with a control. The soils were also analyzed for general soil properties. The results show that total respiration without exudate addition was highest in grassland soil, intermediate in fixed dune and lowest in mobile dune soil. However, the proportion of native soil carbon mineralized was highest in mobile dune soil, reflecting the low c/N ratio found there. The exudate effects on cO2-c emissions and other variables differed somewhat between biotopes, but total respiration（including that from the added substrates） was significantly increased in all combinations compared with the control, except for oxalic acid addition to mobile dune soil, which reduced cO2-c emissions from native soil carbon. A small but statistically significant increase in pH by the exudate additions in grassland and fixed dune soil was observed, but there was a major decrease from acid additions to mobile dune soil. In contrast, electrical condu

关键词： artificial root exudates carbon mineralization pH variation deteriorated grassland ecosystem Inner Mongolia

changes in lipid metabolism in chronic hepatitis c

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World Journal of Gastroenterology 2005年第41期11卷 6422-6428页

作者： Katalin Jármay Gizella Karácsony andrás Nagy Zsuzsa Schaff First Department of Internal Medicine Albert Szent-Gy(o|¨)rgyi Medical University SzegedHungary county Hospital Department of cardiology KecskemétHungary 2nd Department of Pathology Semmelweis University BudapestHungary

AIM: To investigate the relationship between certain biochemical parameters of lipid metabolism in the serum and steatosis in the ***: The grade of steatosis (0-3) and histological activity index (HAI, 0-18) in liver biopsy specimens were correlated with serum alanine aminotransferase (ALT), total cholesterol and triglyceride levels in 142 patients with chronic hepatitis c (cH-c), and 28 patients with non-alcoholic fatty liver disease (NAFLD) without hepatitis c virus (HcV) infection. The serum parameters were further correlated with 1 797 age and sex matched control patients without any liver ***: Steatosis was detected in 90 out of 142 specimens (63%) with cH-c. The ALT levels correlated with the grade of steatosis, both in patients with cH-c and NAFLD (P＜0.01). Inserting the score values of steatosis as part of the HAI, correlation with the ALT level (P＜0.00001) was found. The triglyceride and cholesterol levels were significantly lower in patients with cH-c (with and without steatosis), compared to the NAFLD group and to the virus-free control ***: Our study confirms the importance of liver steatosis in cH-c which correlates with lower lipid levels in the sera. Inclusion of the score of steatosis into HAI, in case of cH-c might reflect the alterations in the liver tissue more precisely, while correlating with the ALT enzyme elevation.

关键词： Lipid metabolism, chronic hepatitis c NAFLD

Mesozoic Evaniidae (Insecta:Hymenoptera) in Spanish Amber:Reanalysis of the Phylogeny of the Evanioidea

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Acta Geologica Sinica(English Edition) 2010年第4期84卷 809-827页

作者： Enrique PEnalVER Jaime ORTEGA-BLANcO andré NEL Xavier DELcLOS Patrimonio Geologico Instituto Geologico y Minero de EspanaE-28003MadridSpain Departament d'Estratigrafia Paleontologia i Geociencies MarinesFacultat de GeologiaUniversitat de BarcelonaE-08071BarcelonaSpain UMR cNRS 7205 EntomologieMuseum National d'Histoire NaturelleF-75005ParisFrance

One new genus and five new species of the family Evaniidae are described from the Early cretaceous （Albian） Spanish amber of Pefiacerrada-I （Province of Burgos）, San Just and Arroyo de la Pascueta （both in the Province of Teruel）： cretevania alonsoi sp. nov., c. montoyai sp. nov., c. alcalai sp. nov., c. rubusensis sp. nov., and lberoevania roblesi gen. and sp. nov. Taxonomic changes include cretevania pristina （Zhang and Zhang, 2000） comb. nov., c. exquisita （Zhang, Rasnitsyn, Wang and Zhang, 2007） comb. nov., c. vesca （Zhang, Rasnltsyn, Wang and Zhang, 2007） comb. nov., and c. cyrtocerca （Deans, 2004） comb. nov., as a result of the reinterpretation of the genera Procretevania and Eovernevania. The new well preserved specimens of the genus cretevania, together with the characters shown by the type specimens of the synonymized genera, give new information about their anatomical characters of taxonomical importance, and the genus cretevania Rasnitsyn, 1975 is re-diagnosed. The holotypes of the Russian species in amber have been revised. A cladistic analysis of fossil and extant groups of the superfamily Evanioidea is included. cretevania had a wide palaeogeographic distribution, with the highest diversity known from Spain. The 13 known cretevania species show a high interspecific variation mainly in wing characteristics, and a wide range of body and wing size.

关键词： Eovernevania Procretevania cretevania lberoevania New taxa Early cretaceous amber

Record of Early Tonian mafic magmatism in the central Espinhaco(Brazil):New insights for break-up of the Neoproterozoic landmass ancestor of Sao Francisco-congo paleocontinent

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Geoscience Frontiers 2020年第6期11卷 2323-2337页

作者： Helen F.Moreira andréDanderfer Alice F.O.costa Samuel M.Bersan cristiano c.Lana Gláucia N.Queiroga Post Graduate Program of Department of Geology Mine SchoolFederal University of Ouro PretoBrazil Department of Geology Mine SchoolFederal University of Ouro PretoBrazil

Petrological characterization,U-Pb geochronology,Lu-Hf analyses and major and trace element data from mafic intrusions in the central Espinhaco(central portion of the Brazilian shield)are used here to investigate the geological significance of the Early Neoproterozoic magmatism in the context of the Sao Francisco-congo *** mafic bodies are represented by medium to coarse-grained metagabbros with plagioclase,amphibole and *** U-Pb isotopic data from two samples yielded weighted mean 206pb/238U ages of 895±3.4 Ma(MSWD=1.7)and 896±2.4 Ma(MSWD=0.64),regarded as the best estimates for the crystallization age of these mafic *** and trace element data(including REEs)show that the gabbros originated from a subalkaline tholeiitic magma,typical of intraplate *** rocks are slightly enriched in LREEs and LILEs and depleted in *** new isotope and geochemical data,along with regional knowledge,indicate that these metagabbros mark the beginning of an important Tonian-age extensional tectonic event of the landmass of which the Sao Francisco-congo paleocontinent was part(Rodinia supercontinent or central African block?).We furthermore suggest that these rocks belong to a prominent suite of Tonian-age mafic rocks that mark a diachronic breakup attempt of this landmass which may have occurred from south to north along the Espinhaco mountain range.

关键词： Mafic rocks Espinhaco basin Sao Francisco-congo paleocontinent Tonian rifting U–Pb geochronology

cholangiocarcinoma:early detection and screening in high-risk population

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Hepatoma Research 2022年第1期8卷 352-362页

作者： Sergio Muñoz-Martínez Jordi Rimola María carlota Londoño andrés cárdenas Alejandro Forner Barcelona clinic Liver cancer(BcLc)group Liver UnitICMDMHospital Clinic BarcelonaIDIBAPSUniversity of BarcelonaBarcelona 08036Spain Barcelona clinic Liver cancer(BcLc)group Radiology DepartmentHospital Clinic BarcelonaIDIBAPSBarcelona 08036Spain Liver Unit ICMDMHospital Clinic BarcelonaIDIBAPS.University of BarcelonaBarcelona 08036Spain GI/Liver Transplant Unit ICMDMHospital Clinic BarcelonaIDIBAPSUniversity of BarcelonaBarcelona 08036Spain centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas(cIBERehd) MadridSpain

cholangiocarcinoma(ccA)is a highly lethal malignancy that comprises approximately 15%of all the primary liver tumors and 3% of gastrointestinal *** is often done when the disease is already at advanced stages,resulting in poor *** of risk factors and early diagnosis are the cornerstones for improving *** diagnosis is feasible in the setting of surveillance programs in patients at high risk of ccA such as patients with primary sclerosing ***,surveillance of ccA in this population is hampered by the low diagnostic accuracy of current tumor markers at earlier stages,the difficulties of imaging techniques for the differential diagnosis between benign and malignant biliary strictures,and the need for invasive procedures for diagnostic *** this review we discuss the rationale for surveillance of ccA in high-risk populations,particularly patients with primary sclerosing cholangitis,the recommended tools for surveillance and diagnostic work-up,and future perspectives.

关键词： Surveillance cholangiocarcinoma primary sclerosing cholangitis magnetic resonance tumor biomarker

Ruthenium promotion of co/SBA-15 catalysts for Fischer-Tropsch synthesis in slurry-phase reactors

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Journal of Natural Gas chemistry 2012年第6期21卷 722-728页

作者： Jocielys Jovelino Rodrigues Gina Pecchi Fabiano andrNarciso Fernandes Meiry Glucia Freire Rodrigues Federal University of campina Grande Academic Unit of Chemical Engineering Facultad de ciencias Químicas Departamento de Físico-QuímicaUniversidad de Concepción Federal University of ceara Department of Chemical Engineering

The aim of this work was to evaluate the catalytic properties of a Ru promoted co/SBA-15 catalyst for Fischer-Tropsch synthesis （FTS）. The Ru promoted co/SBA-15 catalyst was prepared by wet impregnation method and was characterized by X-ray diffraction, X-ray energy dispersion spectrophotometer, N2 adsorption-desorption, temperature-programmed reduction and transmission electron microscopy. The Fischer-Tropsch synthesis using the catalyst was carried out to evaluate the catalyst activity and its effect on FTS product distribution. The synthesis was carried out in a slurry reactor operating at 513 K, 20 atm, cO ： H2 molar ratio of 1 ： 1. X-ray diffraction showed that the calcined cobalt catalyst did not modify the structure of SBA-15, proving that co was present in the form of co3O4 in the catalyst. The addition of cobalt in SBA-15 decreased the specific superficial area of the molecular sieve. Fischer-Tropsch synthesis activity and c5＋ hydrocarbon selectivity increased with the addition of Ru. The increases in activity and selectivity were attributed to the increased number of active sites resulting from higher reducibility and the synergetic effect of Ru and co. Ru/co/SBA-15 catalysts showed moderate conversion （40%） and high selectivity towards the production of c5＋（80 wt%）.

关键词： SBA-15 cobalt ruthenium heterogeneous catalyst slurry reactor Fischer-Tropsch synthesis

Blood Flow Simulation in the Femoral Artery

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Journal of Electronic Science and Technology 2018年第3期16卷 269-279页

作者： camilo A.Naranjo andrés F.Villa Juan c.Vélez Ricardo A.Prato Alberto J.cadena Juan P.Tello IPATEc Institute CONICETBariloche R8400 Integra IT Bogotá 602 the Electronic and Electric Engineering Department Universidad del NorteBarranquilla 1569 the Institute of Mathematics Universidad de AntioquiaMedellin 050010 the cardiology Department Clínica de la CostaBarranquilla 080020

This paper presents the development of the blood flow simulation in two dimensions over the real geometry of the femoral artery. The Navier-Stokes equations are solved using the finite element method, to obtain the distributions of the blood pressure and flow velocity in multiple instants of time and different places of the femoral artery and thus determine the current condition of the blood vessels. The velocity field shows a laminar behavior,where, the velocity is higher in the center of the artery and decreases as the blood flow approaches artery walls. In spite of all artery and blood flow properties not being considered, the values of pressure and velocity obtained are within the normal ranges. Finally the model is used to verify if there exist irregularities in the blood flow in both healthy subjects and sick patients.

关键词： Blood flow femoral artery finite elements Navier-Stokes pressure velocity

Helicobacter pylori cagA protein polymorphisms and their lack of association with pathogenesis

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World Journal of Gastroenterology 2010年第31期16卷 3936-3943页

作者： Nicole Acosta andrés Quiroga Pilar Delgado María Mercedes Bravo carlos Jaramillo Molecular Diagnostics and Bioinformatics Laboratory Biological Sciences DepartmentLos Andes University Infectious Agents and cancer Research Group National Cancer Institute(Colombia)

AIM: To investigate Helicobacter pylori (H. pylori) cagA diversity and to evaluate the association between protein polymorphisms and the occurrence of gastric pathologies. METHODS: One hundred and twenty-two clinical isolates of H. pylori cultured from gastric biopsies obtained from colombian patients with dyspepsia were included as study material. DNA extracted from isolates was used to determine cagA status, amplifying the c-terminal cagA gene region by polymerase chain reaction. One hundred and six strains with a single amplicon were sequenced and results were used to characterize the 3' variable region of the cagA gene. To establish the number and type of tyrosine phosphorylation motifs Glutamine acid-Proline-Isoleucine-Tyrosine-Alanine (EPI-YA) bioinformatic analysis using Amino Acid Sequence Analyzer-Amino Acid Sequence Analyzer software was conducted. Analysis of the association between the number of EPIYA motifs and the gastric pathology was performed using χ2 test and analysis of the presence of EPIYA-c motifs in relation to the pathology was made by logistic regression odds ratios. comparisons among EPIYA types found and those reported in GenBank were performed using a proportion test in Statistix Analytical Software version 8.0. RESULTS: After amplification of the 3' of the cagA gene, 106 from 122 isolates presented a single amplicon and 16 showed multiple amplicons. As expected, diversity in the size of the cagA unique fragments among isolates was observed. The 106 strains that presented a single amplicon after 3' cagA amplification came from patients with gastritis (19 patients), atrophic gastritis (21), intestinal metaplasia (26), duodenal ulcer (22) and gastric cancer. DNA sequence analysis showed that the differences in size of 3' cagA unique fragments was attributable to the number of EPIYA motifs: 1.9% had two EPIYA motifs, 62.3% had three, 33.0% had four and 2.8% had five motifs. The majority of tested clinical strains (62.3%) were found to harbor

关键词： Helicobacter pylori cagA-protein polymorphisms Molecular characterization Bioinformatic analysis Pathogenesis cancer

Punctual mutations in 23S rRNA gene of clarithromycinresistant Helicobacter pylori in colombian populations

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World Journal of Gastroenterology 2018年第14期24卷 1531-1539页

作者： andrés Jenuer Matta Diana carolina Zambrano Alvaro Jairo Pazos Registro Poblacional de cáncer de cali Department of Pathology School of Medicine Universidad del Valle Faculty of Education and Sports Sciences Institución Universitaria Escuela Nacional del Deporte Department of Biology Universidad de Nari?o

AIM To characterize punctual mutations in 23S rRNA gene of clarithromycin-resistant Helicobacter pylori(H. pylori) and determine their association with therapeutic *** PcR products of 23S rRNA gene V domain of 74 H. pylori isolates; 34 resistant to clarithromycin(29 from a low-risk gastric cancer(Gc) population: Tumacocolombia, and 5 from a high-risk population: Tuquerrescolombia) and 40 from a susceptible population(28 from Tumaco and 12 from Túquerres) were sequenced using capillary electrophoresis. The concordance between mutations of V domain 23S rRNA gene of H. pylori and therapeutic failure was determined using the Kappa coefficient and Mc Nemar's test was performed to determine the relationship between H. pylori mutationsand clarithromycin ***23S rRNA gene from H. pylori was amplified in 56/74 isolates, of which 25 were resistant to clarithromycin(20 from Tumaco and 5 from Túquerres, respectively). In 17 resistant isolates(13 from Tumaco and 4 from Túquerres) the following mutations were found: A1593 T1, A1653 G2, c1770 T, c1954 T1, and G1827 c in isolates from Tumaco, and A2144 G from Túquerres. The mutations T2183 c, A2144 G and c2196 T in H. pylori isolates resistant to clarithromycin from colombia are reported for the first time. No association between the H. pylori mutations and in vitro clarithromycin resistance was found. However, therapeutic failure of eradication treatment was associated with mutations of 23S rRNA gene in clarithromycin-resistant H. pylori(κ = 0.71).cONcLUSION The therapeutic failure of eradication treatment in the two populations from colombia was associated with mutations of the 23S rRNA gene in clarithromycinresistant H. pylori.

关键词： clarithromycin In vitro resistance Point mutation Helicobacter pylori Gastric cancer 23S rRNA