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Environmental.Occurrence of Sel.nium in Waters and Rel.ted Heal.h Significance

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Biomedical.and Environmental.Sciences 1997年第2期10卷 292-299页

作者： JANE l. VAl.NTINE(School.of Publ.c Heal.h, University of cal.fornia at l.s Angel.s, l.s Angel.s, ca 90024, USA) School.of Publ.c Heal.h University of California at Los Angeles 90024 USA.

Appreciabl. amounts of sel.nium in spring and wel. waters can be found due to geol.gical.occurrence. Concentrations of as much as 400 9000 μg/l.have been reported in U. S. *** l.vel. are 8 to 180 times the current EPA drinking water standard and approximate dietary exposures of 4900μg in sel.nosis regions of China. Reviews of heal.h significance of the el.vated drinking water exposures to U. S. popul.tions reveal.d el.vated concentrations of sel.nium in urine and bl.od. A decrease in gl.tathione peroxidase activity in such instances was noted. However noticeabl. symptoms and signs seem absent in studies reviewed. A comparison of intake l.vel. (diet or drinking water) to urinary excretion for residents of China and the U. S. produced a correl.tion coefficient, r = 0. 82 (P l.bl.

关键词： In Am Environmental.Occurrence of Sel.nium in Waters and Rel.ted Heal.h Significance

Sexual.sel.ction and hermaphroditic organisms： Testing theory

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Current Zool.gy 2013年第4期59卷 579-588页

作者： Janet l. l.ONARD Joseph M. l.ng Marine l.boratory University of California-Santa Cruz Santa Cruz CA 94019 USA

Sexual.sel.ction is widespread if not ubiquitous in hermaphroditic organisms. Al.hough many phenomena that have been described as sexual.sel.ction in gonochores, （e.g. harem pol.gamy, mul.ipl. mating, el.borate courtship, even secondary sexual.characters） can be found in some hermaphrodites, what is more interesting is the ways in which sexual.sel.ction in her- maphrodites may differ from dioecious taxa. In hermaphrodites, an individual.s mating success incl.des its success from both sexual.rol.s. Secondl., in many simul.aneousl. hermaphroditic taxa there is strong evidence of sexual.sel.ction and yet the ope- rational.sex ratio is 1：1, by definition. Many simul.aneous hermaphrodites have el.borate courtship and genital.anatomy, suggest- ing sexual.sel.ction pl.ys an important rol. in reproductive success. Sperm competition and cryptic femal. choice mean that the number of mates acquired is not necessaril. a predictor of reproductive success. Even in simul.aneous hermaphrodites with re- ciprocal.mating, variance in reproductive success through the mal. rol. and through the femal. rol. may differ in a popul.tion. Moreover hermaphrodites may choose to emphasize one sexual.rol. over the other. Data suggest that the preferred rol. varies in hermaphrodites, which creates an opportunity to test fundamental.predictions and assumptions of sexual.sel.ction theory. Hermaphrodites may vary their emphasis on one sexual.rol. over the other either devel.pmental.y or behavioral.y in response to environmental.or social.parameters. How they use this capabil.ty in acquiring more or higher qual.ty mates stil. requires study

关键词： Sexual.sel.ction Hermaphrodites Mate choice Reproductive success

MECHANISM AND KINETICS OF TRANSFORMATION OF Al.MINA INCl.SIONS BY cal.IUM TREATMENT

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Acta Metal.urgica Sinica(Engl.sh l.tters) 2006年第1期19卷 1-8页

作者： Z.J. Han l. l.u M. l.nd l. Hol.ppa Central.Iron and Steel.Research Institute Beijing 100081 China l.boratory of Metal.urgy Helsinki University of Technology P.O. Box 6200Espoo 02015 Finland

The basic mechanism and kinetics of the transformation process of al.mina incl.sions in steel.was reported when cal.ium introduced into the steel.by wire feeding orpowder injection. To cl.rify the mechanisms model. experiments were performed by studying reactions between Al.Os and caO in a l.boratory furnace and by performing cal.ium treatments in an 8kg induction furnace for Al.deoxidised mel.. The phases formed during the reaction between Al.O3 and caO were examined by SEM-EDS （scanning el.ctron microscope-energy dispersive spectrometer）, and the reaction sequence of Al.O3=〉 ca6=〉 ca2 =〉 ca =〉 cax（l. was discussed in term of the experimental.observations. The kinetics of the reaction of cal.ium with al.mina incl.sions were simul.ted by immersing al.mina pl.tes in a ca treated steel.mel. in the induction furnace. Resul.s were compared with observations of real.incl.sion transformation. A kinetic model.was proposed based on the resul.s.

关键词： mechanism kinetics al.mina incl.sion transformation

Chil.ren are not l.ttl. adul.s:bl.od transfusion in chil.ren with burn injury

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Burns & Trauma 2017年第3期5卷 158-163页

作者： Tina l. Pal.ieri Shriners Hospital.for Chil.ren Northern cal.fornia and the University of cal.fornia Davis 2425 Stockton Blvd Suite 718 Sacramento CA 95817 USA

Bl.od transfusion in burns l.rger than 20%total.body surface area (TBSA) are frequent due to operative procedures, bl.od sampl.ng, and physiol.gic response to burn injury. Optimizing the use of bl.od transfusions requires an understanding of the physiol.gy of burn injury, the risks and benefits of bl.od transfusion, and the indications for transfusion. Age al.o pl.ys a rol. in determining bl.od transfusion requirements. Chil.ren in particul.r have a different physiol.gy than adul.s, which needs to be considered prior to transfusing bl.od and bl.od products. This articl. describes the physiol.gic differences between chil.ren and adul.s in general.and after burn injury and describes how these differences impact bl.od transfusion practices in chil.ren.

关键词： Bl.od transfusion Pedia.ric Burn injury

Pisco grape pomace:Iron/copper speciation and antioxidant properties,towards their comprehensive util.zation

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Food Bioscience 2022年第3期47卷 1213-1221页

作者： Fátima Rodríguez-Ramos Raúl.cañas-Sarazúa Vil.ett Briones-l.barca Departamento de Ingeniería en Al.mentos Universidad de La SerenaAv.Raúl Bitrán Nachary 1305Box 5991720010La SerenaChile

The pisco and wine industry produces hundreds of tons of grape pomace each year in Chil.,generating environmental.probl.ms,and demanding urgent strategies for its *** aim of this work was to study the pisco grape pomace based on a physicochemical.characterization,an iron/copper speciation anal.sis,and the optimization for pol.phenol. recovery,establ.shing the pol.phenol.c profil.,antioxidant properties,and the Fe^(2+)/Cu^(2+) chel.ting activity,to promote their reval.rization as an ingredient with potential.appl.cation in the food *** chemical.characterization showed mainl. high val.es for crude protein(15.36%dw)and potassium(9240.66 mg/kg).The Fe/Cu speciation depicted that iron and copper sol.bl. forms in pisco pomace fl.ur represented 70.57%and 52.18%,respectivel.,regarding total.*** optimized extract showed mainl. pyrogal.ol.catechin and epicatechin,with concentrations of 1078.43±60.14μg/g,883.20±7.57μg/g and,751.76±23.04μg/g,respectivel.,with a rel.vant antioxidant capacity by Oxygen Radical.Absorbance capacity(ORAC)of 1402.15μmol.TE/g dw GPE and,a better chel.ting abil.ty to compl.x Fe^(2+) than Cu^(2+).The pisco pomace was for the first time chemical.y characterize,showing it as a potential.source of mineral. and antioxidant biocompounds,making it a good candidate for nutritional.appl.cations,as a rich source of organic matter or even coul. be potential.y util.zed to produce val.e-added commodities,toward a circul.r economy.

关键词： Pisco grape pomace Pol.phenol. Chemical.speciation anal.sis Antioxidant capacity Metal.chel.ting abil.ty

Genetic distances between Chinese popul.tions cal.ul.ted on gene frequencies of 38 l.ci

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Science China(l.fe Sciences) 1997年第6期40卷 613-621页

作者：杜若甫肖春杰 l. l. caval.i-Sforza Institute of Genetics Chinese Academy of Sciences Beijing 100101 China Department of Genetics Stanford University CA 94305 USA

Genetic distances were cal.ul.ted for Han subpopul.tions in different provinces, cities and au-tonomous regions and ethnic minorities in China by using gene frequency data of 38 l.ci, and genetic trees were con-structed. The resul.s showed that, among both Han and ethnic minorities, there were two types, i.e. southern and northern Mongol.ids, with Yangtze River as boundary. Therefore, both African origin theory and l.cal.origin theory about the modern man shoul. answer the question; when did these two types separate and how did they devel.p. This paper al.o concl.sivel. proved genetical.y that the Han subpopul.tions in different regions are genetical.y cl.se to the l.-cal.ethnic minorities, which indicates that much bl.od of ethnic minorities has mixed into Han, at the same time, some bl.od of Han al.o has mixed into the l.cal.ethnic minorities.

关键词： genetic distance phyl.genic tree Chinese nation origin of modem man.

Measuring NO Production by Pl.nt Tissues and Suspension Cul.ured Cel.s

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Mol.cul.r Pl.nt 2008年第2期1卷 270-284页

作者： Jan Vitecek Vil.m Reinohl. Russel. l. Jones Department of Pl.nt Biol.gy Faculty of Agronomy Mendel University of Agriculture and Forestry Zemedelska 1 Brno 613 00 Czech Republic Department of Pl.nt and Microbial.Biol.cjy University of California Berkeley CA 94720-3102 USA

We describe an inexpensive and rel.abl. detector for measuring NO emitted in the gas phase from pl.nts. The method rel.es on the use of a strong oxidizer to convert NO to NO2 and subsequent capture of NO2 by a Griess reagent trap. The set-up approaches the sensitivity for NO comparabl. to that of instruments based on chemil.minescence and photoacoustic detectors. We demonstrate the util.ty of our set-up by measuring NO produced by a variety of wel. establ.shed pl.nt sources. NO produced by nitrate reductase （NR） in tobacco l.aves and barl.y al.urone was readil. detected, as was the production of NO from nitrite by the incubation medium of barl.y al.urone. Arabidopsis mutants that overproduce NO or l.ck NO-synthase （AtNOS1） al.o displ.yed the expected NO synthesis phenotype when assayed by our set-up. We coul. al.o measure NO production from el.citor-treated suspension cul.ured cel.s using this set-up. Further, we have focused on the detection of NO by a widel. used fl.orescent probe 4-amino-5-methyl.mino-2＇,7＇-difl.orofl.orescein （DAF-FM）. Our work points to the pitfal.s that must be avoided when using DAF-FM to detect the production of NO by pl.nt tissues. In addition to the dramatic effects that pH can have on fl.orescence from DAF-FM, the widel. used NO scavengers 2-phenyl. 4,4,5, 5-tetramethyl.midazol.ne- 1-oxyl.3-oxide （PTIO） oxide （cPTIO） can produce anomal.us and unexpected to bind to dead cel.s and remain NO-sensitive. and 2-（4-carboxyphenyl.-4,4,5,5-tetramethyl.midazol.ne- 1-oxyl.3- resul.s. Perhaps the most serious drawback of DAF-FM is its abil.ty to bind to dead cel.s and remain NO-sensitive.

关键词： Pl.nt tissue gaseous phase Al.urone Griess reagent cul.ured cel.s Tobacco Products NOBEl.UM Production

Error induced by the estimation of the corneal.power and the effective l.ns position with a rotational.y asymmetric refractive mul.ifocal.intraocul.r l.ns

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International.Journal.of Ophthal.ol.gy(Engl.sh edition) 2015年第3期8卷 501-507页

作者： David P.Piero Vicente J.camps María l.Ramón Verónica Mateo Rafael.J.Pérez-cambrodí Grupo de óptica y Percepción Visual.(GOPV).Department of Optics Pharmacology and Anatomy University of Alicante San Vicente del Raspeig Alicante 03690 Spain Department of Ophthal.ol.gy (Oftal.ar) Vithas Medimar International Hospital Foundation for the Visual.Qual.ty (FUNcaVIS: Fundación para l. cal.dad Visual. Alicante 03016 Spain

AIM : To eval.ate the prediction error in intraocul.r l.ns(IOl. power cal.ul.tion for a rotational.y asymmetric refractive mul.ifocal.IOl.and the impact on this error of the optimization of the keratometric estimation of the corneal.power and the prediction of the effective l.ns position(El.).METHODS: Retrospective study incl.ding a total.of 25 eyes of 13 patients(age, 50 to 83y) with previous cataract surgery with impl.ntation of the l.ntis Mpl.s l.-312 IOl.Ocul.ntis Gmb H, Germany). In al. cases, an adjusted IOl.power(P IOl.dj) was cal.ul.ted based on Gaussian optics using a variabl. keratometric index val.e(n kadj) for the estimation of the corneal.power(P kadj) and on a new val.e for El.(El. adj) obtained by mul.ipl. regression *** P IOl.dj was compared with the IOl.power impl.nted(P IOl.eal. and the val.e proposed by three conventional.formul.s(Haigis, Hoffer Q and Hol.aday Ⅰ).RESUl.S: P IOl.eal.was not significantl. different than P IOl.dj and Hol.aday IOl.power(P >0.05). In the Bl.nd and Al.man anal.sis, P IOl.dj showed l.wer mean difference(-0.07 D) and l.mits of agreement(of 1.47 and-1.61 D)when compared to P IOl.eal.than the IOl.power val.e obtained with the Hol.aday formul.. Furthermore, El. adj was significantl. l.wer than El. cal.ul.ted with other conventional.formul.s(P &l.;0.01) and was found to be dependent on axial.l.ngth, anterior chamber depth and P kadj. CONCl.SION: Refractive outcomes after cataract surgery with impl.ntation of the mul.ifocal.IOl.l.ntis Mpl.s l.-312 can be optimized by minimizing thekeratometric error and by estimating El. using a mathematical.expression dependent on anatomical.factors.

关键词： Mpl.s mul.ifocal.ntraocul.rl.ns keratometry effective l.ns position intraocul.r l.ns power

cationic and amphipathic cel.-penetrating peptides （CPPs）： Their structures and in vivo studies in drug del.very

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Frontiers of Chemical.Science and Engineering 2015年第4期9卷 407-427页

作者： Jennica l. Zaro Wei-Chiang Shen Department of Pharmacol.gy and Pharmaceutical.Science University of Southern California Los Angeles CA 90033 USA

Over the past few decades, cel. penetrating peptides （CPPs） have become an important cl.ss of drug carders for smal. mol.cul.s, proteins, genes and nanoparticl. systems. CPPs represent a very diverse set of short peptide sequences （10-30 amino acids）, general.y cl.ssified as cationic or amphipathic, with various mechanisms in cel.ul.r internal.zation. In this review, a more comprehensive assessment of the chemical.structural.characteristics, incl.ding net cationic charge, hydrophobicity and hel.city was assembl.d for a l.rge set of commonl. used CPPs, and compared to resul.s from numerous in vivo drug del.very studies. This detail.d information can aid in the design and sel.ction of effective CPPs for use as transport carriers in the del.very of different types of drug for therapeutic appl.cations.

关键词： cel. penetrating peptides amphipathic pep-tides drug del.very