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American Journal of Analytical Chemistry 2013年第3期4卷 125-133页

作者： Jan Prech václav Matousek Jiriváclavik Jan Pechacek Kamila Syslova petr Sot Jakub Januscak Beáta vilhanová Marek Kuzma Jaromir Toman petr Kacer Department of Organic Technology Institute of Chemical TechnologyPragueCzech Republic Laboratory of Molecular Structure Characterization Institute of MicrobiologyAcademy of Sciences of the Czech RepublicPragueCzech Republic

A method for the analysis of the optical purity of a series of chiral substituted tetrahydroisoquinolines (THIQs) was developed. The method is based on pre-column derivatization of the analytes with the derivatization reagent (–)-(1R)-menthyl chloroformate. The derivatization reaction selectively gives diastereomeric carbamates that are resolvable on an achiral non-polar GC column. The developed technique covers variously substituted THIQs, which differ significantly in volatility, steric and electronic properties. In all cases, the resolution factors (R) exceeded the value of 1.5. The method represents a robust way of analysis of mixtures of THIQs, which are often present in various matrixes such as body fluids, tissues and reaction mixtures.

关键词： Tetrahydroisoquinolines Enantiomeric Composition Derivatization Menthyl Chloroformate Gas Chromatography

The effect of neodymium substitution on the structural and magnetic properties of nickel ferrite

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Progress in Natural Science:Materials International 2015年第3期25卷 215-221页

作者： ?srafil ?abiko?lu Levent Paral? Ondrej Malina petr Novak Josef Kaslik Jiri Tucek Jiri Pechousek Jakub Navarik Oldrich Schneeweiss Celal Bayar University Faculty of Arts&SciencesDepartment of Physics 45140 Muradiye Celal Bayar University Department of Electronics and Automation Regional Centre of Advanced Technologies and Materials Department of Experimental Physics and Physical ChemistryFaculty of SciencePalacky University Institute of Physics of Materials of the Academy of Sciences of the Czech Republic

Nickel ferrite Ni Fe2O4 is a typical soft magnetic ferrite with high electrical resistivity used as high frequency magnetic material. Neodymium(Nd3+) doped Ni Fe2O4 materials were fabricated using solid state reaction. The properties of the obtained material were investigated by X-Ray Diffraction(XRD), Scanning Electron Microscope(SEM), Fourier-Transform Infrared Spectroscopy(FT-IR), magnetic measurements on SQUID and M?ssbauer spectroscopy. It was found that the material consists of two different phases: Nd3+doped Ni Fet2O4and Nd Fe O3. The Nd3 ions occupy cation sites of the Ni Fe2O4 inverse spinel structure. NdFeO3 phase occurred when the level of Nd3+atoms exceed a percolation *** presence of both phases was confirmed by SEM observations. The M?ssbauer spectra analysis showed two sextets, which can be ascribed to iron atoms in tetrahedral and octahedral positions. From their intensities it is concluded that Nd3+occupies octahedral sites in the spinel structure of Ni Fe2O4, which were originally occupied by Ni2+.

关键词： NiFe2O4 Neodymium Solid-state reaction Magnetic properties M?ssbauer spectroscopy

Spontaneous liver rupture following SARS-Cov-2 infection in late pregnancy:A case report

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World Journal of Clinical Cases 2022年第15期10卷 5042-5050页

作者： Radek Ambroz Martin Stasek Ján Molnár petr Spicka Dusan Klos Jozef Hambálek Daniela Skanderová Department of Surgery I University Hospital Olomouc and Faculty of Medicine and DentistryPalacky UniversityOlomouc 77900Czech Republic Department of Obstetrics and Gynecology University Hospital Olomouc and Faculty of Medicine and DentistryPalacky UniversityOlomouc 77900Czech Republic Department of Pathology University Hospital Olomouc and Faculty of Medicine and DentistryPalackýUniversityOlomouc 77900Czech Republic

BACKGROUND Coronavirus disease-2019(COvID-19)caused by severe acute respiratory syndrome coronavirus 2(SARS-Cov-2)is characterized by systemic inflammatory response syndrome and ***-Cov-2 associated mortality ranges from 2%to 6%.Liver dysfunction was observed in 14%-53%of COvID-19 cases,especially in moderate severe ***,no cases of spontaneous hepatic rupture in pregnant women with SARS-Cov-2 have been *** SUMMARY A 32-year-old pregnant patient(gestational age:32 wk+4 d)without any remarkable medical history or long-term medication presented with ***,non-infectious,and pregnancy-related hepatopathies were *** onset of right subcostal pain with D-dimer and liver enzyme elevation was followed by shock with *** performing an emergency cesarean section,hemoperitoneum was observed,and the patient delivered a stillbirth.A 6-cm liver rupture at the edges of segments v and vI had occurred,which was sutured and ***-Cov-2 positivity on reverse transcriptionpolymerase chain reaction was *** revisions for intrahepatic hematoma with hemorrhagic shock and abdominal compartment syndrome were ***,the patient developed hemoptysis,which was treated using bronchoscopic therapy and non-invasive *** tissue biopsy revealed hemorrhagic foci and necrosis with an irregular centrilobular *** syndrome and autoimmune hepatitis were also ruled *** death was caused by acute intrauterine *** This case reveals that pregnant women with SARS-Cov-2 infection may be predisposed to liver parenchyma disease with liver rupture.

关键词： Liver rupture SARS-Cov-2 Pregnancy Abortion HELLP Case report

Inflammatory bowel disease incidence in Czech children:A regional prospective study,2000-2015

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World Journal of Gastroenterology 2017年第22期23卷 4090-4101页

作者： Jan Schwarz Josef Sykora Dominika Cvalínová Renáta Pomahacová Jana Klecková Martin Kryl petr vcelák Department of Paediatrics Charles UniversityFaculty of Medicine in PilsenFaculty Hospital Department of Computer Science and NTIS-Research Centre Faculty of Applied SciencesUniversity of West Bohemia

AIM To examine the incidence and trends in pediatric inflammatory bowel diseases(IBDs) over 2000-2015 and project the incidence to 2018. METHODS A 16-year prospective study of IBD patients ved from a prospectively collected computerized clinical database. Historical Czech data were used for comparison(1990-2001). Our catchment population was determined from the census data. We calculated the incidence by relating the number of newly diagnosed cases to the size of thepediatric population-at-risk in each calendar year. Age/sex, disease type, place of residence, and race/ethnicity were identified. RESULTS In total, 170 new IBD cases [105 Crohn's disease(CD), 48 ulcerative colitis(UC), and 17 IBD-unclassified(IBD-U)] were identified. The median age at IBD diagnosis was 14.2 years, 59.4% were males, and 97.1% were Caucasians. A male preponderance of IBD(P = 0.026) and CD(P = 0.016) was observed. With 109209 person-years in the catchment area, the average incidence of IBD per 100000 person-years was 10.0(6.2 for CD, 2.8 for UC, and 1.0 for IBD-U) for children aged 0 to 19 years; for those aged 0 to 15 years, the incidence rate was 7.3(4.6 for CD, 2.0 for UC, and 0.7 for IBD-U). An increase in incidence with age was observed(P = 0.0003). Over the 16-year period, the incidence increased for IBD patients(P = 0.01) and CD in particular(P < 0.0001), whereas the incidence for UC(P = 0.09) and IBD-U(P = 0.339) remained unchanged. IBD-projected data from 2016 to 2018 were 12.1, 12.3 and 12.6 per 100000 personyears, *** Pediatric-onset IBD incidence is around its highest point. The increase, which is particularly pronounced for CD, may be challenging to relate to causes of pediatric disease.

关键词： Inflammatory bowel disease Incidence Children Czech Republic Pilsen region Projections Crohn’s disease Ulcerative colitis

Phase State and Thermodynamical Principles in Porous Systems

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材料科学与工程（中英文版） 2011年第4期5卷 478-488页

作者： Leonid Skatkov petr Cheremskoy 4/23 Shaul ha-Melekh Street 84797 Beer Sheva Israel

A Study of the Behavior of Alkyl Side Chains Phenols and Arenes in Polar and Nonpolar GC Stationary Phases

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American Journal of Analytical Chemistry 2011年第3期2卷 324-331页

作者： Pavel Straka petr Buryan Institute of Rock Structure and Mechanics Academy of Sciences of the Czech Republic Prague Czech Republic.

Gas chromatographic measurements of the relative retention times of alkyl-substituted arenes and phenols on capillary columns at temperatures of 125 – 140°C have shown that logarithms of retention times increase bilinearly with the number of carbon atoms in the molecule. It was found that in a high density stationary phase, the longer alkyl side chains of compounds in question are subject to cyclization as a result of the resistance force of this phase affecting molecules during their thermal and diffusion motion. Consequently, common conventional aromatic-aliphatic molecules become new molecules with quasi-alicyclic rings. In comparison with the conventionally conceived molecules, the resulting aromatic–quasi-alicyclic molecules are characterized by rather different, possibly even completely different non-covalent interactions between the molecules, which then affect the retention characteristics. Moreover, cyclization facilitates the mixing of n-alkyl arenes and n-alkyl phenols with high-molecular stationary phases, because the thermodynamic condition for mixing is better fulfilled.

关键词： Alkyl Phenols Alkyl Benzenes Retention Times Molecular Mechanics van der Waals Forces

Model of Freight Transportation between the Czech Republic and the US

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Journal of Civil Engineering and Architecture 2015年第4期9卷 475-484页

作者： Helena Binova petr Toman Faculty of Transportation Sciences Czech Technical University Praha 110 00 Czech Republic

Maritime transportation is one of the most important and extensive transportation modes in the world. Maritime transportation is the backbone of contemporary world trade and therefore special attention should be paid to all subjects concerning this mode of transportation. It is also necessary to complement maritime transportation by other modes, such as rail and/or truck （road）. This article deals with the problems of maritime transportation and provides the summary of recent developments, trends and statistics mainly on transatlantic maritime routes （Europe to US）. Besides maritime transportation, this thesis also reviews the trends and statistics of rail and truck （road） transportation in US and Europe. The authors considers four Czech biggest cities （points of origin）, five European ports, eight US ports and 10 biggest cities in US （points of destination）. The adapted TCMMSP （transnational collaborative multi-mode shipping problem） is applied to this case study and it seeks to solve the transportation of a set of five shipments with unique O-D （origin-destination） pairs and volume. The end of the thesis summarizes the results and analyses the average costs, optimal set volume, optimal shipment routing and port analysis.

关键词： Maritime transport freight trade Czech Republic US.

Primitive Mammoth Hunters and the Earliest Breed of Dog

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Natural Resources 2014年第3期5卷 99-105页

作者： petr N. Kolosov Diamond and Precious Metal Geology Institute Siberian Branch Russian Academy of Sciences Yakutsk Russia

Primitive man have managed to survive in the rigorous climatic conditions of the arctic regions in northeast Asia owing to the hunting for mammoth, bison, wooly rhinoceros and other Pleistocene mammals with the assistance of the laika, a domesticated wolf. This is how the colonization of the Arctic began. The domestic dog appeared in this region about 25 - 30 thousand years ago as a result of the severe climatic conditions in which both hunting tribes and the ancestors of the domestic dog had to live. A wolf is a predator, an able hunter. Therefore, most likely wolves were originally trained to hunt with humans—the leaders of the hunting pack. Thus, in northeast Asia, there was a direct relationship between man’s colonization of the Arctic, the appearance of the hunting dog, and a decrease in the number of mammoth, bison, and other large animals in the region, as a result of hunting when whole herds were killed.

关键词： Asia Arctic Paleolithic Mammoth Primitive Hunter Wolf Domestication Dog

ApoB-containing lipoproteins promote infectivity of chlamydial species in human hepatoma cell line

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World Journal of Hepatology 2010年第2期2卷 74-80页

作者： Yuriy K Bashmakov Nailia A Zigangirova Alexander L Gintzburg petr A Bortsov Ivan M Petyaev Cambridge Theranostics Ltd Babraham Research CampusBabrahamCambridgeCB2 4ATUnited Kingdom Gamaleya Institute for Epidemiology and Microbiology RAMS 18 Gamaleya Str.Moscow 123098Russia

AIM:To evaluate the direct binding of two main chlamydial biovars(*** and ***) to plasma lipoproteins and its effect on chlamydial infection rate in human hepatoma cell line(HepG2 cells). METHODS:Murine plasma lipoproteins were fractionated and isolated using fast-performance liquid chromatography(FPLC),spotted on nitrocellulose membrane and incubated with chlamydial suspensions. Direct binding of chlamydial particles to lipoprotein fractions has been studied using lipopolysaccharide-specific antibodies in immuno-dot blot binding assay and immunoprecipitation *** protocol as well as flow cytometry analysis have been employed to study the infectivity rate of chlamydial species in HepG2 cells. RESULTS:Elementary bodies of both *** and *** bind ApoB-containing fractions of plasma *** binding becomes stronger when heat-denatured FPLC fractions are used, suggesting a primary role of apolipoproteins in interaction between chlamydial particle and lipoprotein. Both chlamydial biovars efficiently propagate in human hepatoma cell line-HepG2 cells even in serum free conditions forming late-stage inclusion bodies and releasing extracellular elementary *** of *** and *** with native ApoB-containing lipoproteins enhances the rate of chlamydial infection in HepG2 ***:A productive infection caused by C. trachomatis and *** may take place in human-derived hepatocytes revealing hepatic cells as possible target in chlamydial *** results may suggest the participation of lipoprotein receptors in the mechanism of attachment and/or entry of chlamydial particles into target cells.

关键词： ApoB-containing lipoproteins Chlamydial trachomatis Chlamydial pneumoniae Human hepatoma cell line Liver infection

Antibacterial properties of lucifensin in Lucilia sericata maggots after septic injury

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Asian Pacific Journal of Tropical Biomedicine 2014年第5期4卷 358-361页

作者： Ivana valachova Emanuel Prochazka Jana Bohova petr Novak Peter Takac Juraj Majtan Institute of Zoology Slovak Academy of Sciences Institute of Microbiology Academy of Sciences of the Czech Republic Scientica s.r.o.

Objective:To investigate the antibacterial properties of lucifensin in maggots of IjicUia sericala after septic ***:In our preliminary study we have shown that injuring the maggots with a needle soaked in lipopolysaccharide solution induced within 24 h lucifensin expression in the fat body and in the grease coupler of the salivary *** is assumed that lucifensin is secreted solely from this tissue into the haemoiymph(similar to other insect defensins) and not into secreted/excreted *** used high-performance liquid chromatography fractionation and radial diffusion assay to investigate the antibacterial properties of haemoiymph extracted from larvae after septic ***:After septic injury,production of lucifensin in the haemoiymph is *** led to higher antibacterial activity of such haemoiymph in comparison to non-stimulated ***:These results suggest that beside the previously demonstrated role of lucifensin in the debridement therapy,lucifensin is simultaneously important as a part of the systematic immune response.

关键词： Lucilia sericata Wound bacteria Defensin Lucifensin Immune-challenge