Three-dimensionally Perforated Calcium Phosphate Ceramics

1Introduction Calciumphosphateceramicswithopenporousstruc tureandsufficientmechanicalstrengthareusefulfor combingmedicines,growthfactorsandcellswiththece ramicsbecausetheopenporescanbeusedasthespace forpreservingthesesubstancesandcells.However,most ofconv…     

Preparation of Porous Calcium Phosphate Bioceramic

1Introduction Humanlongbonehasgradientstructure,whichis thattheouterlayeriscortical(ie,dense)boneandthe innerlayeristrabecular(ie,spongy)bone.Thecortical boneconsistsofcylindricalchannelsthatareheldtogether byaframeworkofhardtissue,mainlynaturalcalcium ph…     

可注射磷酸钙骨水泥的研究

可注射磷酸钙骨水泥具有良好的生物相容性、骨传导性、可降解性、易操作性及可塑性等优点，临床上可用于非负重部位骨缺损的修复、药物或生物因子载体、牙根管的充填、松质骨螺钉的加固以及骨折的固定等方面，在植入学、骨创伤学及放射介入学等领域中具有广泛的应用前景。目前可注射磷酸钙骨水泥已经成为骨水泥研究中的主要课题，就其最新研究进展进行了讨论。     

磷酸钙陶瓷纤维的研究

用前驱体法制备出了磷酸钙陶瓷纤维，运用Ｘ－射线衍射仪、扫描电镜等测试手段，对磷酸钙纤维的组成进行了分析，结果表明：Ｎａ－Ａｌｇ（海藻酸钠）／Ｎａ４Ｐ２Ｏ７比和烧结温度等对纤维的矿物组成有很大影响。当ＮａＡｌｇ／Ｎａ４Ｐ２Ｏ７比大于２．８时，可以得到羟基磷灰石（ＨＡＰ）和缺钙型ＨＡＰ（ＤＨＡＰ）纤维；将ＨＡＰ＋ＤＨＡＰ纤维加热到１１００℃时，有β－ＴＣＰ产生，温度高于１２００℃时β－ＴＣＰ能形成稳定的α－ＴＣＰ。     

聚合磷酸钙骨水泥的制备和性能研究

采用丙烯酸和衣康酸的共聚物与自制磷酸钙粉末反应制备骨水泥。用自凝牙托水对类磷酸四钙（TTCP）粉末进行表面改性后所制备的骨水泥,初凝时间为4．5min,终凝时间为8.5min,抗压强度可达４２MPa。采用类TTCPα－磷酸三钙的混合粉料制备的骨水泥,初凝时间为５．５min,终凝时间为１１．０min,抗压强度可达４３MPa。     

Porous Calcium Phosphate Ceramic Scaffolds for Tissue Engineering

1Introduction Thereisamajorclinicalandsocio economicneedtogeneratenewboneforskeletaluse.Autogenousgraftsandallogenicbonegraftshavebeenusedformanyyearsbutbothhavedisadvantages,includingthefailureofcompleteresorptionofautogenousbone,difficultiesinshapingthe…     

The Transformation of Calcium Phosphate Bioceramics in Vivo

1　IntroductionThefactthatthemineralphaseofbonesandteethiscomposedofcalciumphosphatesaltshasdirectedre searcherstoinvestigatethesematerialsaspotentialcandi datesforbonesubstitutes .Calciumphosphateceramics(CPC) ,whicharemadeofbeta tricalciumphosphate (β TCP) ,hydroxyapatiteortheirmixture ,withahighbio compatibilityandgoodbioaffinityandanosteoconduction ,arecurrentlyusedasbonegraftsubstitutes[1-3 ] .Anidealbonegraftingmaterialshouldbereplaceablebythehostboneafterimplantation .Therefore ,the…     

利用氯化石蜡副产盐酸制取沉淀磷酸钙

采用氯化石蜡副产盐酸制取沉淀磷酸钙的不去渣脱氟两段中和流程，重点对萃取磷酸液的脱氟、一段中和及ＣａＣｌ２的回收利用等工艺条件进行了研究，试验结果表明，利用此副产盐酸制取沉淀磷酸钙（饲肥比为６：４）在技术、经济上都是完全可行的。     

Pathogenic Mineralization of Calcium Phosphate on Human Heart Valves

1Introduction Inhumanbodies,themainbiomineralsarecalcium phosphateinhardtissuessuchasbonesandteethbesides calciumoxalatestones[1]inkidneysandcalciumcarbonate inears.Whenbiomineralizationabnormallyoccursinsoft tissues,itiscalledpathogenicmineralizationorpa…     

Preparation of Laminin-apatite-polymer Composites Using Metastable Calcium Phosphate Solutions

1Introduction Themostimportantrequirementofapercutaneous deviceisthepreventionofbacterialinfectionthroughtheinterfacebetweenthematerialandtheskin.Therefore,a percutaneousdevicehastoadherefirmlytoskintissueandpreventepidermaldowngrowth.Previously,Aokietalp…     

Preparation of Laminin-apatite-polymer Composites Using Metastable Calcium Phosphate Solutions

A synthetic polymer with a laminin-apatite composite layer on its surface would be useful as a percutaneous device. The preparation of such a composite was attempted in the present study using poly（ ethylene terephthalate ） （PET） and polyethylene （PE） as the synthetic polymer. PET and PE plates and those pretreated with an oxygen plasma were alternately dipped in calcium and phosphate ion solutions, and then immersed in a metastable calcium phosphate solution supplemented with laminin （ LCP solution ）. The PET and PE plates pretreated with an oxygen plasma formed a uniform and continuous layer of a laminin-apatite composite on their surfaces. In contrast, the PET and PE plates that had not been pretreated with an oxygen plasma did not form a continuous layer of a laminin-apatite composite on their surfaces. The hydrophilic functional groups on the PET and PE surfaces introduced by the plasma treatment were responsible for the successful laminin-apatite coruposite coating.     

Calcium Phosphate Coating over Silk Fibroin Film by Biomimetic Methods

1Introduction Silkfibroin(SF)providesanimportantsetofmate rialoptionsforbiomaterialsandscaffoldsfortissueengi neeringbecauseofitsimpressivemechanicalproperties,biocompatibilityandbiodegradability[1].Tofabricateanorganic inorganiccompositescaffold forbonet…     

磷石膏制备磷酸氢钙的实验研究

以磷石膏中钙源回收利用为研究目的,采用磷酸与磷石膏制得的硫氢化钙反应,制备饲料级磷酸氢钙产品.研究结果表明:磷石膏制备磷酸氢钙路径可行;湿法磷酸和热法磷酸均可制备出符合国家标准的饲料级磷酸氢钙产品;两者相比,采用湿法磷酸在成本上具有优势,采用热法磷酸在品质方面具有优势.实验结果对磷石膏的综合利用具有一定的指导意义.     

饲钙生产中脱氟的必要性

简要介绍了饲钙的用途、市场状况、湿法磷酸生产饲钙中脱氟的必要性以及湿法线路和热法线路的比较。     

The In-situ Reinforcement of Calcium Phosphate Cement and Its Micro-structural Analysis

1Introduction CPC(calciumphosphatecements)havebecomethe hotspotoftheresearchofbonesubstitutematerialssince BrownandChow[1]hadreported.Theyhaveexcellent propertiessuchasself setting,biocompatibilityandosteo conductivity,etc[2,3].Tillnow,theyhavebecomewell …     

一种新型蛋白质大分子印迹杂化聚合物微球的制备

采用反相悬浮法,通过引入磷酸氢二铵,制备了大分子印迹的磷酸钙/海藻酸钙(CP/CA)杂化微球.研究结果表明,采用本文的制备技术可以方便地获得球形和透明性良好的大分子印迹微球,并且湿态凝胶微球的表观机械强度优于纯海藻酸钙微球.红外光谱测试研究结果表明,微球中出现了新的杂化组分.紫外光谱对重结合行为的研究表明,大分子印迹微球的重结合容量得到显著提高.该基材可以作为一种新的蛋白质大分子印迹聚合物基材.     

Evaluation of Calcium Phosphate Cement As a Root Canal Sealer Filling Material

Calcium phosphate cement for root end seeding was obtained by mixing α-tricalcium phosplitue and additives with an aqueous solution of citric . Powder and liquid were mixed at a ratio of 1.25 g/ mL. The biocompatibility of this material was investigated primarily by subcutaneous implantation tests . Then calcium phos-phate cement was used to fill three adult dogs ' root canal, both calcium hydroxide paste and hydroxyapatite paste as control. The animals were killed at 4,12,20 weeks postoperatively respectively. The effects of different materials on the apical closure, restoration of periapical tissues and adaptability to the dentinal surface were examined by optical and electronic microscope . The observation at 20 weeks shows that the calcium phosphate cement, has the potentialities of being a root canal sealer filling material available for pulpless teeth with open-apex and destructive periapical tissue.     

Effects of Additives on Sintering and Characterization of Calcium Phosphate Ceramics

Calcium phosphate precursory powders containing Na and Mg have been prepared by the citric acid sol-gel combustion method. The elements of Na and Mg were introduced from component of CaO- P2O5 - Na2O- MgO. The effect of sintering additives on the phase cornposition was characterized by XRD. The effect of sintering additives on sintering of materials was also characterized by linear shrinkage, TEM and SEM. Finally the microstructure of porous calcium phosphate ceramic was determined by SEM.