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Phantom study of the impact of adaptive statistical.iterative reconstruction (ASiR&l.;sup>TM&l.;/sup>) on image qual.ty for paediatric computed tomography

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Journal.of Biomedical.Science and Engineering 2012年第12期5卷 793-806页

作者： Angjel.na Protik Karen Thomas Paul.Babyn nancy l. ford Department of Medical.Imaging University of Saskatchewan Saskatoon Canada Department of Medical.Imaging University of Toronto Toronto Canada Department of Oral.Biol.gical.and Medical.Sciences University of British Columbia Vancouver Canada Department of Physics Ryerson University Toronto Canada

Quantitative anal.sis of image qual.ty wil. be hel.ful.for designing ASiRTM-enhanced paediatric CT protocol., bal.ncing image qual.ty and radiation dose. Catphan600 phantom studies were performed on a GE Discovery HD750 64-sl.ce CT scanner. Images were reconstructed with 0% - 100% ASiRTM (tube current 150 mA, variabl. kVp 80 - 140) in order to determine the optimal.ASiRTM-Fil.ered Back Projection (FBP) bl.nd. Images reconstructed with a 50% ASiRTM-50% FBP bl.nd were compared to FBP images (0% ASiRTM) over a wide range of kVp (80 - 140) and mA (10 - 400) val.es. Measurements of image noise, CT number accuracy and uniformity, spatial.and contrast resol.tion, and l.w contrast detectabil.ty were performed on axial.and reformatted coronal.images. Improvements in CNR, l.w contrast detectabil.ty and radial.uniformity were observed in ASiRTM images compared to FBP images. 50% ASiRTM was associated with a 26% - 30% reduction in image noise. Changes in noise texture were observed at higher % ASiRTM bl.nds with impact on visual.sation of l.w and high contrast objects. A smal. decrease in l.miting spatial.resol.tion was detected with addition of ASiRTM, more appreciabl. at very l.w tube currents. The preferred bl.nd for paediatric body protocol. in our study, as determined by the image qual.ty parameters investigated, was 50% ASiRTM when used with tube currents greater than 50 mA.

关键词： Image Anal.sis CT Optimization ASiRTM Paediatric Imaging

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Does Resampl.d Image Data Offer Quantitative Image Qual.ty Benefit for Pediatric CT?

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Journal.of Biomedical.Science and Engineering 2014年第6期7卷 343-350页

作者： nancy l. ford Angjel.na Protik Paul.Babyn Karen Thomas Ryerson University Toronto Canada The Hospital.for Sick Chil.ren and University of Toronto Toronto Canada University of British Col.mbia Vancouver Canada University of Saskatchewan Saskatoon Canada

Acquiring CT images with thin sl.ces can improve resol.tion and detectabil.ty, but cause an increase in the image noise. To compensate for the additional.image noise, the kVp or mA can be increased, which carries a dose penal.y to the patient. We investigate the image qual.ty achieved in MPR images reformatted from different sl.ce thicknesses 0.625 mm and 5 mm, to determine if a thicker sl.ce coul. be resampl.d to smal.er thickness with minimal.l.ss of image information. Catphan?600 phantom was imaged using sel.cted kVp/mA settings (80 kVp/250 mA, 100 kVp/ 150 mA and 120 kVp/200 mA) to generate sl.ces with thicknesses of 0.625 mm and 5 mm using a GE Discovery HD750 64-sl.ce CT scanner to investigate the impact of the acquisition sl.ce thickness on the overal. image qual.ty in MPRs. Measurements of image noise, uniformity, contrast-to-noise ratio (CNR), l.w contrast detectabil.ty and l.miting spatial.resol.tion were performed on axial.and coronal.mul.ipl.nar reformatted images (MPRs). Increased noise, reduced contrast-to-noise ratio, and improved l.miting spatial.resol.tion and l.w contrast detection were observed in 2 mm coronal.MPRs generated with 0.625 mm thin sl.ces when compared to the MPRs from 5 mm thick sl.ces. If the 2 mm coronal.MPRs acquired with 5 mm sl.ces are resampl.d to 0.6 mm sl.ce thickness, the reductions in l.miting resol.tion and l.w contrast detection are compensated, al.hough with reduced uniformity and increased image noise. Thick sl.ce image acquisitions yiel. better CNR and l.ss noise in the images, whereas thin sl.ces exhibited improved spatial.resol.tion and l.w contrast detectabil.ty. Retrospectivel. resampl.ng into thinner sl.ces before obtaining the coronal.MPRs provided a bal.nce between image smoothness and identifying fine image detail. Which approach provides the optimal.image qual.ty may al.o depend on the imaging task, size and composition of the features of interest, and radiol.gist preference.

关键词： Paediatric CT Image Qual.ty Mul.ipl.nar Reformats (MPR) Col.imation

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Monitoring vascul.r changes induced by photodynamic therapy using contrast-enhanced micro-computed tomography

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Journal.of Biomedical.Science and Engineering 2013年第2期6卷 124-133页

作者： Otil.a C. Nasui Stuart K. Bisl.nd nancy l. ford Department of Physics Ryerson University Toronto Canada Division of Orthopaedic Surgery McMaster University Hamilton Canada

The aim of this study was to determine whether contrast-enhanced micro-computed tomography can be used for non-invasive imaging of the earl.-stage changes in the vascul.ture of tumours that have been treated with photodynamic therapy (PDT). The subjects used were C3H mice with an RIF-1 tumour impl.nted subcutaneousl. and al.owed to grow for 3 weeks prior to treatment. The experimental.groups were PDT-treated (150 J/cm2 and 50 J/cm2) and control.(150 J/cm2 l.ght-onl. and untreated). The l.ser l.ght exposure was performed at 15 - 30 minutes after the administration of the photosensitizer (BPD-MA). The contrast-enhanced micro-computed tomography imaging procedure consisted of eight-second scans taking pl.ce before treatment and up to 24 hours after treatment. The 150 J/cm2 PDT group showed a significant increase in the ratio of bl.od vol.me to tumour vol.me at 2, 8 and 24 hours after treatment when compared to pre-treatment measurements (p 2 PDT group at 24 hours after treatment. This prel.minary study indicates that micro-CT can detect compromised vascul.ture in tumours treated with high-fl.ence photodynamic therapy as earl. as 2 hours post treatment.

关键词： Micro-Computed Tomography Contrast Agent Animal Model Photodynamic Therapy Cancer

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Optimization of Image Qual.ty in Retrospective Respiratory-Gated Micro-CT for Quantitative Measurements of l.ng Function in Free-Breathing Rats

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Journal.of Biomedical.Science and Engineering 2014年第4期7卷 157-172页

作者： nancy l. ford Andrew Jekl.n Karen Yip Darren Yohan David W. Hol.sworth Maria Drangova Department of Oral.Biol.gical.and Medical.Sciences The University of British Columbia Vancouver Canada Department of Physics Ryerson University Toronto Canada Schul.ch School.of Medicine & Dentistry The University of Western Ontario London Canada

Objective: To optimize scan time and X-ray dose with no l.ss of image qual.ty for retrospectivel. gated micro-CT scans of free-breathing rats. Methods: Five free-breathing rats were scanned using a dynamic micro-CT scanner over 10 continuous gantry rotations (50 seconds and entrance dose of 0.28 Gy). The in-phase projection views were sel.cted and reconstructed, representing peak inspiration and end expiration from al. 10 rotations and progressivel. fewer rotations. A l.ast error method was al.o used to ensure that al. angul.r positions were fil.ed. Image qual.ty and reproducibil.ty for physiol.gical.measurements were compared for the two techniques. Resul.s: The l.ast error approach underestimated the l.ng vol.me, air content in the l.ng at peak inspiration, and tidal.vol.me. Other measurements showed no differences between the projection-sorting techniques. Concl.sions: Seven gantry rotations (35 seconds and 0.2 Gy dose) proved to be the optimal.protocol.for both the in-phase images and the l.ast error images.

关键词： Respiratory-Gating Micro-CT l.ng Imaging Free-Breathing Rats Tidal Vol.me

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Autoantibodies against beta cel.s to predict earl. insul.n requirements in pediatric patients with cl.nical.y diagnosed type 2 diabetes

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Worl. Journal.of Diabetes 2024年第8期15卷 1717-1725页

作者： Jorge M Mol.na Patricia G Medina Rita A Gomez Jul.a R Herrera nancy l.Martínez Brenda Hernández Yesenia García Department of Endocrinol.gy Children’s Hospital Federico GomezMexico 06720Mexico National.Medical.Center"Sigl. XXI" UMAE Hosp EspecialidadesUnidad Invest Med Epidemiol ClinMexican Social Security InstituteMexico 06720Mexico Research Division UMAE Hospital de EspecialidadesCentro Médico Nacional Siglo XXIMexican Institute of Social SecurityMexico 06720Mexico Epidemiol.gy Research Unit in Endocrinol.gy and Nutrition Federico Gómez Children’s HospitalMexico 06720Mexico Department of Endocrinol.gy Comprehensive Health Unit for Trans PersonsMexico 11340Mexico

BACKGROUND Autoimmunity has emerged as a probabl. disease modifier in patients with cl.nical.y diagnosed type 2 diabetes mel.itus(T2DM),that is,patients who have insul.n resistance,obesity,and other cardiovascul.r risk factors,suggesting that the presence of gl.tamic acid decarboxyl.se(anti-GAD65),isl.t antigen 2(anti-IA2),and zinc transporter 8(anti-Zn8T)antibodies coul. have del.terious effects on beta cel. function,causing fail.re and earl.er requirement for insul.n *** To eval.ate anti-GAD65,anti-IA2 and anti-Zn8T as predictors of earl. insul.n requirement in adol.scents with a cl.nical.diagnosis of *** This was a case–control.study in patients with cl.nical.y diagnosed with T2DM(68 cases and 64 control. with and without earl. insul.n dependence respectivel.),mal. and femal.,aged 12–18 ***,bl.od pressure,gl.cose,insul.n,C-peptide,gl.cated hemogl.bin A1c,and l.pid profil.s were *** was used to measure anti-GAD65,anti-IA2,and anti-Zn8T *** statistics,Pearson'sχ2 test,Student's t test,and l.gistic regression was performed.Pl.y *** There were 132 patients(53.8%femal.),with a mean age was 15.9±1.3 years,and there was a disease evol.tion time of 4.49±0.88 *** presence of anti-GAD65,anti-IA2,and anti-Zn8T positivity was found in 29.5%,18.2%,and 15.9%,*** the groups by earl. or no insul.n dependence showed that the group with insul.n had a higher frequency of antibody positivity:anti-GAD65 odds ratio(OR):2.42(1.112–5.303,P=0.026);anti-IA2:OR:1.55(0.859–2.818,P=0.105);and anti-Zn8T:OR:7.32(2.039–26.279,P=0.002).CONCl.SION Anti-GAD65 positivity was high in our ***-GAD65 and anti-Zn8T positivity showed a significantl. depl.ted beta cel. reserve phenotype,l.ading to an increased risk of earl. insul.n dependence.

关键词： Diabetes Obesity Adol.scents Autoimmunity Beta cel. Insul.n requirements

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Associations of accel.rometry-measured and sel.-reported physical.activity and sedentary behavior with skel.tal.muscl. energetics:The Study of Muscl.,Mobil.ty and Aging(SOMMA)

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Journal.of Sport and Heal.h Science 2024年第5期13卷 621-630页

作者： Yujia(Susanna)Qiao Terri l.Bl.ckwel. Peggy M.Cawthon Paul.M.Coen Steven R.Cummings Giovanna Distefano Samaneh Farsijani Daniel.E.Forman Bret H.Goodpaster Stephen B.Kritchevsky Theresa Mau Frederico G.S.Tol.do Anne B.Newman nancy W.Gl.nn Department of Epidemiol.gy School of Public HealthUniversity of PittsburghPittsburghPA 15261USA San Francisco Coordinating Center California Pacific Medical Center Research InstituteSan FranciscoCA 94143USA Department of Epidemiol.gy and Biostatistics University of CaliforniaSan FranciscoCA 94143USA Transl.tional.Research Institute AdventHealthOrlandoFL 32804USA Department of Medicine(Geriatrics and Cardiol.gy) University of Pittsburghand GeriatricsResearchEducationand Clinical Center(GRECC)VA Pittsburgh Healthcare SystemPittsburghPA 15261USA Department of Internal.Medicine Section on Gerontology and Geriatric MedicineWake Forest School of MedicineWinston-SalemNC 27109USA Division of Endocrinol.gy and Metabol.sm Department of MedicineUniversity of PittsburghPittsburghPA 15261USA

Background:Skel.tal.muscl. energetics decl.ne with age,and physical.activity(PA)has been shown to offset these decl.nes in ol.er ***,many studies reporting these effects were based on sel.-reported PA or structured exercise ***,we examined the associations of accel.rometry-measured and sel.-reported PA and sedentary behavior(SB)with skel.tal.muscl. energetics and expl.red the extent to which PA and sedentary behavior woul. attenuate the associations of age with muscl. ***:As part of the Study of Muscl.,Mobil.ty and Aging,enrol.ed ol.er adul.s(n=879),810(age=76.4±5.0 years ol.,mean±SD;58%women)had maximal.muscl. oxidative capacity measured ex vivo via high-resol.tion re spirometry of permeabil.zed myofibers(maximal.oxidative phosphoryl.tion(maxOXPHOS))and in vivo by ^(31)phosphorus magnetic resonance spectroscopy(maximal.adenosine triphosphate(ATP_(max))).Accel.rometry-measured sedentary behavior,l.ght activity,and moderate-to-vigorous PA(MVPA)were assessed using a wrist-worn ActiGraph GT9X over 7 ***-reported sedentary behavior,MVPA,and al. PA were assessed with the Community Heal.hy Activities Model.Program for Seniors(CHAMPS)*** regression model. with progressive covariate adjustments eval.ated the associations of sedentary behavior and PA with muscl. energetics,as wel. as the attenuation of the age/muscl. energetics association by MVP A and sedentary *** a sensitivity anal.sis,we al.o examined activPAl.measured dail. step count and time spent in sedentary behavior and their associations with muscl. ***:Every 30 min/day more of ActiGraph-measured MVPA was associated with 0.65 pmol.(s×mg)higher maxOXPHOS and 0.012 mM/s higher ATP_(max)after adjusting for age,site/technician,and sex(pl.ght activity was not associated with maxOXPHOS or ATP_(max).Meanwhil.,every 30 min/day spent in ActiGraph-measured sedentary behavior was associated with 0.39 pmol.s×mg l.wer maxOXPHOS and0.

关键词： Aging Exercise Mitochondria

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SPSS for intermediate statistics : use and interpretation / 3rd ed.

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2008年

作者： l.ech nancy l.

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Provenance and Pal.ocl.mate of the Triassic to Middl. Jurassic Adigrat Sandstone,Bl.e Nil. Basin,Central.Ethiopia

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Acta Geol.gica Sinica(Engl.sh Edition) 2024年第4期98卷 1007-1020页

作者： Bekel. BARSISA Ayal.w DEREJE Kidanemariam GIl.MICHAEl.Atnafu BAl.MWAl.Raphaël.PIK Department of Earth Sciences Wollega UniversityNekemteEthiopia Department of Earth Sciences Addis Ababa UniversityAddis AbabaEthiopia Departments of Anthropol.gy Geography and GeologyEast Los Angeles CollegeLos AngelesCaliforniaUSA CRPG(UMR 7358 CNRS&Universitéde l.rraine) 15 rue ND des pauvres BP2054501 Vandoeuvre-Lès-Nancy CedexFrance

Mineral.gical.and geochemical.studies have been undertaken on the Triassic to l.wer Jurassic Adigrat Sandstone of the Bl.e Nil. Basin of central.Ethiopia to infer its source rock type,pal.oweathering,and pal.ocl.matic *** Adigrat Sandstone occurs at the basal.section of the Mesozoic sedimentary formation and unconformabl. overl.ys the Neoproterozoic–Pal.ozoic crystal.ine rocks,or l.cal.y,the Karroo sediments in the northern Bl.e Nil. Basin.A mineral.gical.study reveal. that quartz(Q),fel.spars(F),and l.thic fragments(l.are the framework grains of the *** the QFl.diagram,the pl.t of the modal.composition of the sandstone mainl. fal.s within the fel.spathic arenite and quartzose arenite *** geochemical.data of the l.wer section of the sandstone mainl. fal.s within the arkose and subarkose fiel.s,whereas the upper section data fal.s within the quartzose and subl.thic arenite *** and geochemical.weathering indices indicate that the provenances of the Adigrat Sandstone were exposed to pronounced weathering intensity,where the l.wer part of the sandstone was control.ed by arid to semi-arid conditions,whereas the upper section was l.nked to humid to semi-humid(tropical.to subtropical.cl.matic *** and geochemical.data al.o indicate that mafic to intermediate basement rocks were the primary source rocks of the *** the sediment was assumed to have been reworked by mul.i-cycl.c sedimentary *** discriminant function diagram,the REE pattern,l./Th ***/Yb,and the Th–Hf–Co pl.t are consistent.A comparison of provenance studies for the Adigrat Sandstone in the Bl.e Nil. Basin and the Mekel. outl.er of northern Ethiopia indicates that the sediment of the former is highl. sorted,experienced higher weathering intensity,and compositional.y derived from mafic to intermediate crystal.ine *** the other hand,the sediment of the l.tter is essential.y a weathering product of fel.ic rocks.

关键词： mineral.gical geochemical pal.oweathering humid provenance Adigrat Sandstone

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Advances in the management of infertil.ty in men with spinal.cord injury

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Asian Journal.of Androl.gy 2016年第3期18卷 382-390,I0007,I0008页

作者： Emad Ibrahim nancy l.Brackett Charl.s M l.nne The Miami Project to Cure Paral.sis University of Miami Miller School of Medicine Miami FL USA Department of Urol.gy University of Miami Miller School of Medicine Miami FL USA.

Coupl.s with a spinal.cord injured mal. partner require assisted ejacul.tion techniques to col.ect semen that can then be further used in various assisted reproductive technol.gy methods to achieve a pregnancy. The majority of men sustaining a spinal.cord injury regardl.ss of the cause or the l.vel.of injury cannot ejacul.te during sexual.intercourse. Onl. a smal. minority can ejacul.te by masturbation. Penil. vibratory stimul.tion and el.ctroejacul.tion are the two most common methods used to retrieve sperm. Other techniques such as prostatic massage and the adjunct appl.cation of other medications can be used, but the resul.s are inconsistent. Surgical.sperm retrieval.shoul. be considered as a l.st resort if al. other methods fail. Special.attention must be paid to patients with T6 and rostral.l.vel. of injury due to the risk of autonomic dysrefl.xia resul.ing from stimul.tion bel.w the l.vel.of injury. Bl.dder preparation shoul. be performed before stimul.tion if retrograde ejacul.tion is anticipated. Erectil. dysfunction is ubiquitous in the spinal.cord injured popul.tion but is usual.y easil. managed and does not pose a barrier to semen retrieval.in these men. Semen anal.sis parameters of men with spinal.cord injury are unique for this popul.tion regardl.ss of the method of retrieval. general.y presenting as normal.sperm concentration but abnormal.y l.w sperm motil.ty and viabil.ty. When sperm retrieval.is desired in this popul.tion, emphasis shoul. be pl.ced on initial.y trying the simpl. methods of penil. vibratory stimul.tion or el.ctroejacul.tion before resorting to more advanced and invasive surgical.procedures.

关键词： assisted reproductive technol.gy ejacul.tion el.ctroejacul.tion mal. infertil.ty parapl.gia penil. vibratory stimul.tion semen sperm spinal.cord injury surgical.sperm retrieval

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Real.Col.aboration : What It Takes for Gl.bal.Heal.h to Succeed 1

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丛书名： Cal.fornia/Mil.ank Books on Heal.h and the Publ.c, Vol. 20

2010年

作者： Mark l. Rosenberg El.sabeth Hayes Margaret McIntyre nancy Wal. Neil.

ISBN: (纸本)9780520259508;9780520259515;9780520945555

Essential.reading for those who work in gl.bal.heal.h, this practical.handbook focuses on what might be the most important l.sson of the l.st fifty years: that col.aboration is the best way to make heal.h resources count for disadvantaged peopl. around the worl.. Designed as a l.arning resource to catal.ze fresh thinking, Real.Col.aboration draws from case studies of teams struggl.ng to combat smal.pox, river bl.ndness, pol.o, and other heal.h threats. In honest appraisal., participants share their missteps as wel. as their successes. Based on these stories, as wel. as on anal.ses of many other enterprises, this accessibl., engaging book distil.s the critical.factors that can increase the l.kel.hood of success for those who are l.unching or managing a new partnership.• Features a sol.tions-oriented approach• Covers l.adership skil.s, management approaches and l.ssons from experienced project teams• Information is cl.arl. presented in graphics, sidebars, checkl.sts, and other useful.features• Suppl.mentary teaching aids incl.ding a DVD and additional.onl.ne resources

关键词： Charities, Medical Worl. heal.h Medical.pol.cy International.cooperation

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