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1.
《中国组织工程研究》2010,(16)
背景:采用发泡剂成孔技术,制成了有知识产权的新型骨修复材料多孔碳酸化羟基磷灰石,既保留了碳酸化羟基磷灰石骨水泥原位固化性能等所有的优点,同时又形成多孔结构。目的:通过动物实验观察新型的骨修复材料多孔碳酸化羟基磷灰石水泥修复骨缺损的力学效果。方法:30只新西兰大白兔,手术组25只在双侧股骨髁制备直径为5.5mm、深12mm的骨缺损动物模型,左侧植入多孔碳酸化羟基磷灰石骨水泥为实验组,右侧植入碳酸化羟基磷灰石骨水泥为对照组。非手术组5只,用于正常力学对照。将多孔碳酸化羟基磷灰石骨水泥和碳酸化羟基磷灰石骨水泥试件经模仿体液浸泡,检测力学强度。同时在手术组背肌内分别植入多孔碳酸化羟基磷灰石骨水泥和碳酸化羟基磷灰石骨水泥标准试件。分别于术后2,4,8,12,16周分批处死动物,进行试件骨内和肌内植入的力学实验分析和试件在模仿体液中浸泡后的抗压强度测试。结果与结论:多孔碳酸化羟基磷灰石骨水泥:2周时的骨内力学强度较低,4周时降到最低,8周时接近正常松质骨强度,12周时超过正常松质骨强度,16周时恢复到正常松质骨水平。碳酸化羟基磷灰石骨水泥:2周时骨内植入强度较多孔碳酸化羟基磷灰石骨水泥略高,4周时有所降低,8,12,16周时略升高,但是始终低于正常松质骨的强度。多孔碳酸化羟基磷灰石骨水泥和碳酸化羟基磷灰石骨水泥在SBF中浸泡的抗压强度变化不大。试件植入肌内后抗压强度变化非常显著。结果表明,多孔碳酸化羟基磷灰石水泥具有原位固化性能和一定的力学支撑作用,能作为自体骨移植的一种替代物修复骨缺损。 相似文献
2.
多孔结构对碳酸化羟基磷灰石骨水泥溶解度的影响 总被引:5,自引:0,他引:5
目的探讨碳酸化羟基磷灰石骨水泥中多孔结构存在的意义及其对溶解性能的影响.方法合成能原位固化形成多孔结构的碳酸化羟基磷灰石骨水泥,并通过扫描电镜和模拟体液浸泡实验,观察其孔隙结构和失重率变化.结果多孔碳酸化羟基磷灰石骨水泥固化后的孔隙率为42%,平均孔径为153μm,孔之间以90μm左右的连通孔互相贯通,孔隙结构与松质骨相似.碳酸化羟基磷灰石的多孔结构增加了其比表面积,利于体液循环.经模拟体液浸泡后,其失重率的改变比普通型碳酸化羟基磷灰石骨水泥明显增加,二者差异显著.结论碳酸化羟基磷灰石骨水泥内部的多孔结构能促进其体外溶解. 相似文献
3.
碳酸化羟基磷灰石水泥修复骨缺损的实验研究 总被引:13,自引:1,他引:13
目的通过动物实验观察一种新型的骨修复材料———碳酸化羟基磷灰石水泥修复骨缺损的效果。方法在10只杂种犬肱骨近端制作骨缺损动物模型,采用碳酸化羟基磷灰石水泥修复骨缺损,并以高温烧结羟基磷灰石陶瓷作为对照,分别于术后5天、4周、8周、12周和16周处死动物,通过X线和组织学观察其修复效果。结果碳酸化羟基磷灰石水泥完全充填骨缺损,界面与骨结合紧密,生物相容性良好,并且随着植入时间的延长可逐渐降解并被新生骨爬行替代,与骨整合为一体。而羟基磷灰石陶瓷不能紧密充填骨缺损,在实验期间与骨界面清晰,并且没有见到降解现象。结论碳酸化羟基磷灰石水泥具有原位固化性能,是一种较为理想的新型骨缺损修复材料。 相似文献
4.
抗稀散性碳酸化羟基磷灰石骨水泥的研究 总被引:1,自引:0,他引:1
目的研制一种适合出血部位植骨的碳酸化羟基磷灰石骨水泥代骨材料.方法合成碳酸化羟基磷灰石骨水泥,在固化液中按重量比添加水溶性磷酸化壳聚糖,通过固化时间、抗压强度、残余百分比、X线衍射分析、傅里叶变换红外线分析等检测方法筛选合适的配方.结果添加壳聚糖对碳酸化羟基磷灰石骨水泥的固化时间影响不大,平均固化时间为11~15min,符合临床操作要求.但是对抗压强度影响较大,由39MPa降到31MPa.壳聚糖的添加量为0.4%(质量分数)时,抗稀散达到100%.大于0.5%时,骨水泥的操作性能明显下降.添加量为1.5%时,部分标本发现少量的磷酸八钙形成,羟基磷灰石的转化受到了影响.傅里叶变换红外线分析证明,其固化产物的晶格相中含有5.6%碳酸根成分.结论磷酸化壳聚糖能明显增加碳酸化羟基磷灰石骨水泥的黏度系数,增强钙离子的熬合作用,有效抑制血液渗入材料内部,保证骨水泥的固化反应顺利进行.当壳聚糖的添加量为0.4%时,材料表现出良好的操作性能,抗稀散性达到100%,适合出血部位的骨缺损修复. 相似文献
5.
羟基磷灰石骨水泥中碳酸根存在的意义及其对溶解度的影响 总被引:1,自引:0,他引:1
目的探讨羟基磷灰石骨水泥中碳酸根存在的意义及其对溶解度产生的影响。方法制备碳酸化羟基磷灰石骨水泥,定量分析其固化产物晶体中的碳酸根结构。以磷酸钙骨水泥为对照组,分别预制直径为8mm、高为12mm的圆柱体试样。经模拟体液浸泡后,定期观察、测量每一试样的失重率,对照分析其体外溶解性的差别。结果碳酸化羟基磷灰石骨水泥固化产物的晶体中含有质量浓度5.6%的碳酸根,与自然骨的矿物成分更接近。随着时间的改变,材料在模拟体液中逐渐由白色转为微黄色,棱角逐渐变钝。体视显微镜下观察发现材料表面出现点、坑、片状溶蚀,碳酸化羟基磷灰石骨水泥较磷酸钙骨水泥更明显。失重率的检测表明,酸化羟基磷灰石骨水泥的失重率改变明显高于磷酸钙骨水泥。结论羟基磷灰石骨水泥中碳酸根的存在可增加其溶解度,加快降解速度。 相似文献
6.
背景:在前期的试验中,通过共沉淀法合成了纳米羟基磷灰石/羧甲基壳聚糖-海藻酸钠复合粉体,并与柠檬酸衍生物溶液调和制备出可生物降解、适当力学性能以及较好黏合强度的骨水泥。
目的:验证纳米羟基磷灰石/羧甲基壳聚糖-海藻酸钠复合骨水泥材料对体外兔骨髓基质细胞黏附及增殖的影响,了解材料的生物相容性。
方法:应用共沉淀法制备纳米羟基磷灰石/羧甲基壳聚糖-海藻酸钠复合材料作为骨水泥的固相粉体,将柠檬酸衍生物配制成溶液作为液相调和制备黏合性骨水泥。培养兔骨髓基质细胞,传代扩增后接种到材料上,体外继续培养;以细胞加入无材料的培养皿培养为对照。
结果与结论:体外培养的兔骨髓基质细胞2 d后呈梭形成纤维细胞样,生长良好。有材料实验组细胞数显著多于对照组(P < 0.01)。扫描电镜下骨水泥材料具有良好的多孔网状结构,兔骨髓基质细胞伸出多个伪足样突起,紧密贴附在材料表面。两组细胞均保持持续增殖,2,4,6,和8 d实验组增殖均显著快于对照组(P < 0.01)。提示纳米羟基磷灰石/羧甲基壳聚糖-海藻酸钠复合骨水泥材料具有良好的生物相容性。 相似文献
7.
背景:国内外的研究证实普通碳酸钙陶瓷作为骨替代材料时具有细胞支架作用。
目的:观察多孔碳酸钙陶瓷与成骨细胞的相容性,及作为骨组织工程支架的可能性。
方法:SD大鼠骨髓基质干细胞经矿化诱导培养、扩增并检测证实其已具成骨细胞表型后,分别与多孔碳酸钙陶瓷支架、普通羟基磷灰石陶瓷支架体外复合培养。
结果与结论:骨髓基质干细胞经体外诱导形成成骨细胞,钙结节、Ⅰ型胶原和碱性磷酸酶免疫染色结果阳性。多孔碳酸钙陶瓷支架材料与羟基磷灰石陶瓷材料皆有细胞附着生长,但多孔碳酸钙陶瓷支架材料细胞的黏附能力、增殖活力及成骨活性均强于羟基磷灰石陶瓷材料。提示多孔碳酸钙陶瓷支架材料与SD大鼠骨髓基质干细胞源性成骨细胞有良好相容性。 相似文献
8.
背景:人们对壳聚糖/羟基磷灰石复合多孔生物支架在体内的降解过程并非十分清楚,而且有关其降解产物对成骨细胞的影响研究也较少。
目的:分析大鼠成骨细胞与壳聚糖/羟基磷灰石复合多孔生物支架降解产物的生物相容性。
方法:将培养的第2代大鼠成骨细胞分别在壳聚糖/羟基磷灰石复合支架降解产物浸提液和含体积分数10%胎牛血清的DMEM培养液中培养,培养第2,4,6,8,10天分别对两组细胞做MTT细胞计数,采用联合会推荐法测定细胞碱性磷酸酶活性,采用BCA蛋白定量法测定总蛋白。
结果与结论:在壳聚糖/羟基磷灰石复合多孔生物支架降解产物浸提液中培养的大鼠成骨细胞增殖速度、细胞碱性磷酸酶活性、细胞总蛋白合成及碱性磷酸酶与总蛋白的比值明显高于在体积分数为10%胎牛血清DMEM培养液中培养的细胞(P < 0.05)。表明壳聚糖/羟基磷灰石复合多孔生物支架的降解产物不仅可促进大鼠成骨细胞的黏附、生长和增殖,还可增强其骨化功能,具有较好的生物相容性。中国组织工程研究杂志出版内容重点:生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程全文链接: 相似文献
9.
壳聚糖/纳米羟基磷灰石分层复合支架的生物相容性研究 总被引:2,自引:0,他引:2
制备壳聚糖/纳米羟基磷灰石(CS/nHA)分层复合支架,对其进行细胞毒性评价.分离培养大鼠软骨细胞接种于支架,相差显微镜和扫描电镜观察细胞的黏附及生长情况.动物皮下埋植试验观察其组织相容性.实验结果证实壳聚糖/纳米羟基磷灰石分层复合支架具有良好的生物相容性,有望成为较好的骨软骨组织工程支架. 相似文献
10.
背景:经处理后的珊瑚转化羟基磷灰石具有良好的生物相容性和可降解性,其三维相通的孔隙结构不仅可为种子细胞的黏附、增殖提供足够的内部空间和表面积,而且有利于营养成分的渗透和血管化形成。
目的:对珊瑚转化羟基磷灰石进行细胞相容性和细胞毒性的研究,以初步探讨其应用于牙周组织工程的可行性。
方法:将体外培养的人牙周膜细胞接种到珊瑚转化羟基磷灰石支架上体外三维复合培养,通过细胞计数方法和扫描电镜观察人牙周膜细胞在珊瑚转化羟基磷灰石支架上的附着、生长情况,并设立阴性对照组和阳性对照组,采用MTT测试法和碱性磷酸酶活性检测法评估稀释浓度分别为100%,50%,10%,1%的珊瑚转化羟基磷灰石浸提液对人牙周膜细胞增殖及功能表达的影响。
结果与结论:珊瑚转化羟基磷灰石具有良好的多孔网状结构,人牙周膜细胞在珊瑚转化羟基磷灰石支架上生长旺盛,伸展充分,而不同浓度的材料浸提液对人牙周膜细胞的生长、增殖及碱性磷酸酶活性的影响差异均无显著性意义。提示珊瑚转化羟基磷灰石具有良好的三维空间结构和细胞相容性,且无细胞毒性,有望用作牙周组织工程的支架材料。关键词:珊瑚转化羟基磷灰石;细胞相容性;细胞毒性;支架材料;组织工程
缩略语注释:CHA:coral hydroxyapatite,珊瑚转化羟基磷灰石;HPDLCs:human periodontal ligament cells,人牙周膜细胞
doi:10.3969/j.issn.1673-8225.2012.16.025 相似文献
11.
Over 200 schizophrenic patients belonging to three major and interrelated pedigree complexes have been investigated over the past 30 years in a North Swedish geographically isolated population, presently numbering about 6,000. An intensive investigation of a number of biochemical correlates and genetic markers in a few selected families belonging to one of the major pedigrees has indicated new strategies for the current research program.
Schizophrenia, as defined operationally, is significantly associated with decreased activities of two enzymes (1) blood platelet monoamine oxidase, (2) plasma dopamine-β-hydroxylase, and (3) with the genetic marker Gc2 (group specific antigen). Both enzymes are subject to genetic variation. A positive score for linkage between schizophrenia and low plasma DBH activity has been calculated, but, so far, available data are insufficient for discrimination between linkage and partial contribution of genetically controlled low plasma DBH to the pathogenesis of the disease. Alternatively, both mechanisms could be involved.
As a model for continued research, schizophrenia is explained as based on a double dominant-recessive genotype (Aabb), representing a vulnerability which in about 50 % of cases develops into clinical schizophrenia. It is suggested that the dominant mutation (A) operates on or affects MAO activity, and that the recessive genotype (bb) is instrumental in low variates of DBH activity and very likely such variates within the normal range of physiological variation. Moreover, it is suggested that the combined effects of MAO- and DBH-reduced efficiency on the metabolism of e.g. dopamine could be an essential pathogenic mechanism for the schizophrenic illness which is segregating in this population. 相似文献
Schizophrenia, as defined operationally, is significantly associated with decreased activities of two enzymes (1) blood platelet monoamine oxidase, (2) plasma dopamine-β-hydroxylase, and (3) with the genetic marker Gc
As a model for continued research, schizophrenia is explained as based on a double dominant-recessive genotype (Aabb), representing a vulnerability which in about 50 % of cases develops into clinical schizophrenia. It is suggested that the dominant mutation (A) operates on or affects MAO activity, and that the recessive genotype (bb) is instrumental in low variates of DBH activity and very likely such variates within the normal range of physiological variation. Moreover, it is suggested that the combined effects of MAO- and DBH-reduced efficiency on the metabolism of e.g. dopamine could be an essential pathogenic mechanism for the schizophrenic illness which is segregating in this population. 相似文献
12.
Renal dysplasia and asplenia in two sibs 总被引:2,自引:0,他引:2
A family is reported in which two sibs, one male and the other female, both died within 24 hours of birth with enlarged polycystic kidneys. Postmortem histology in the second child showed gross renal dysplasia. In both children the pancreas was enlarged, nodular and cystic but the liver appeared macroscopically normal. In the second child, histological examination confirmed pancreatic fibrosis with cystic dilation of ducts, but showed portal fibrosis with bile duct proliferation in the liver.
This combination of findings is very reminiscent of those in a girl and her brother reported by Ivemark et al. (1959). The children reported here also showed absence or hypoplasia of the spleen, cardiac anomalies and other features of the Ivemark syndrome (Ivemark 1955), a quite different, usually sporadic, congenital disorder. It is suggested that the children described here have a distinct lethal congenital disorder, probably inherited in an autosomal recessive manner. 相似文献
This combination of findings is very reminiscent of those in a girl and her brother reported by Ivemark et al. (1959). The children reported here also showed absence or hypoplasia of the spleen, cardiac anomalies and other features of the Ivemark syndrome (Ivemark 1955), a quite different, usually sporadic, congenital disorder. It is suggested that the children described here have a distinct lethal congenital disorder, probably inherited in an autosomal recessive manner. 相似文献
13.
Donald O. Rudin 《Medical hypotheses》1982,8(1):17-47
About 1900, modern food selection and processing caused widespread of the B vitamin deficiency diseases of beriberi and pellagra which, for genetic reasons, often expressed as different diseases ranging from bowel and heart disease to dermatoses and psychoses. But the B vitamins merely help convert essential fatty acids (EFA) into the prostaglandin (PG) tissue regulators and it now turns out that, through hydrogenation, milling and selection of w3-poor southern foods, we have also been systematically depleting, by as much as 90%, a newly discovered trace Nordic EFA (w3) of special importance to primates and sole precursor of the PG3(4) series, even as a concurrent fiber deficiency increases body demand for EFA. Since substrate EFA is processed by many B vitamin catalysts, an EFA deficiency will mimic a ypovitaminosis B, i.e., a mixture of beriberi and pellagra resembling vitamin beriberi and pellagra but exhibiting as even more diverse disease. This would consitute a second stage of the Modern Malnutrition and explain why some workers now hold the dominant diseases of modermized societies to be new, nutritionally based, pellagraform yet lipid-related and to range, once again, from heart disease to psychosis. It is an assumption that our dominant diseases are unrelated to each other or are merely revealed by our diagnostic acumen and therapeutic success; and that hydrogenating millions of tons of food oils annually, to destroy the rancidity producing w3-EFA, is safe for . Extensive beriberiform disease is reported here in 32 typical cases taken from medical practice which responds strikingly to linseed oil supplements (60% w3-EFA) in confirmation of identical results in Capuchins. 相似文献
14.
15.
Newton H 《Medical history》2011,55(2):153-182
Sick children were ubiquitous in early modern England, and yet they have received very little attention from historians. Taking the elusive perspective of the child, this article explores the physical, emotional, and spiritual experience of illness in England between approximately 1580 and 1720. What was it like being ill and suffering pain? How did the young respond emotionally to the anticipation of death? It is argued that children’s experiences were characterised by profound ambivalence: illness could be terrifying and distressing, but also a source of emotional and spiritual fulfilment and joy. This interpretation challenges the common assumption amongst medical historians that the experiences of early modern patients were utterly miserable. It also sheds light on children’s emotional feelings for their parents, a subject often overlooked in the historiography of childhood. The primary sources used in this article include diaries, autobiographies, letters, the biographies of pious children, printed possession cases, doctors’ casebooks, and theological treatises concerning the afterlife. 相似文献
16.
C. R. Lipton J. X. Dautlick G. D. Grothaus P. L. Hunst K. M. Magin C. A. Mihaliak F. M. Rubio J. W. Stave 《Food and Agricultural Immunology》2000,12(2):153-164
Recent advancements in agricultural biotechnology have created a need for analytical techniques to determine introduced proteins in crops enhanced through modern biotechnology techniques. These proteins are expressed in plant tissues and may be present in food ingredients. Immunoassays are ideally suited for protein detection and may be used as both quantitative and threshold methods. Microplate ELISA and lateral flow devices are two of the most commonly used immunoassay formats for agricultural biotechnology applications. This paper provides general background information and a discussion of criteria for the validation and application of immunochemical methods to the analysis of proteins introduced into plants and food ingredients using biotechnology methods. It is the result of a collaborative effort of members of the Analytical Environmental Immunochemical Consortium. This collaborative effort represents the combined expertise of several organizations to reach consensus on establishing guidelines for the validation and use of immunoassays. Further, the paper offers developers and users a consistent approach to adopting the technology as well as aid in producing accurate and meaningful results. 相似文献
17.
Antonio Arnaiz-Villena Jose Palacio-Grüber Ignacio Juarez Ennio Hernández Ester Muñiz Brayan Bayona Cristina Campos Jorge Nieto Manuel Martin-Villa Carlos Silvera 《Human immunology》2018,79(4):189-190
HLA-A,-B,-C,-DRB1 and -DQB1 alleles have been studied in Chimila Amerindians from Sabana de San Angel (North Colombian Coast) by using high resolution molecular typing. A frequent extended haplotype was found:HLA-A*24:02-B*51:10-C*15:02-BRB1*04:07-DQB1*03:02 (28.7%) which has also been described in Amerinndian Mayos Mexican population (Mexico, California Gulf, Pacific Ocean). Other haplotypes had already been found in Amerindians from Mexico (Pacific and Atlantic Coast), Peru (highlands and Amazon Basin), Bolivia and North USA. A geographic pattern according to HLA allele or haplotype frequencies is lacking in Amerindians, as already known. Also, five new extended haplotypes were found in Chimila Amerindians. Their HLA-A*24:02 high frequencies characteristic is shared with aboriginal populations of Taiwan; also, HLA-C*01:02 high frequencies are found in New Zealand Maoris, New Caledonians and Kimberly Aborigines from Australia. Finally, this study may show a model of evolutionary factors acting and rising one HLA allele frequency (-A*24:02), but not in others that belong to the same or different HLA loci. 相似文献
18.
Ultracryotomy: development and application (with examples from the yeast cytology) (author's transl)
Konrad Joachim Böhm 《Acta histochemica》1980,66(1):59-84
The preparation steps usually necessary for obtaining ultrathin frozen sections of biological material (chemical prefixation, enclosing, cryoprotective treatment, freezing, sectioning, and post-staining the sections for transmission electron microscopy) are submitted to a critical analysis. The application of cryo-ultramicrotomy, in particularly for cytochemical purposes, is reviewed. Fundamental considerations of chemical prefixation and poststaining are supported by examples from yeast cytology. Furthermore, the efficiency of the cryo-ultramicrotomy (electron optical resolution of ultrastructural details) is demonstrated on yeast cells and protoplasts. 相似文献
19.
M G Baggot 《Medical hypotheses》1979,5(5):591-597
Starting with the integument, we see many organs are contractile sacs or multiples thereof, which tubes or bags constitute the major part of the entire body. Recognition of this basic unit and its characteristics sheds new light, individually and collectively, on many disorders previously considered unrelated. Muscular tears and perforations develop in the walls of these chambers, being no way peculiar to those organs, wherein, hydrochloric acid occurs. So, it is not necessary to explain the absence of excessive acid from patients who exhibit holes in the gastric, uterine, aortic, duodenal, rectal, pulmonary, retina, and other walls. Muscle, not acid is the great common factor relating idiopathic disorders in the gastrointestinal tract to each other and to similar diseases in other systems. When the units are linked together, the lesions tend to appear as arthropathies, i.e. at the joints. Rephrasing common-place observations, frees us from conventional, conceptual cul-de-sacs. An observation is only as good as its interpretation, so all possibilities must be considered, otherwise, we will remain blinded by our misconceptions. 相似文献
20.
G. Heinemann H. Schievelbein D. Eberhagen V. Rahlfs 《Journal of molecular medicine (Berlin, Germany)》1981,59(20):1165-1173
Zusammenfassung Der Einfluß von verschiedenen Nahrungsmitteln auf Methoden zur Bestimmung von Adrenalin (AD), Noradrenalin (NA), Vanillinmandelsäure (VMS), Metanephrinen (MN), Homovanillinsäure (HVS) und 5-Hydroxyindolessigsäure (5-HIE) im 24 h-Harn zur Diagnose des Phäochromozytoms bzw. Karzinoid-Syndroms wurde untersucht. Die in die Untersuchung einbezogenen Nahrungsmittel waren: Tee, Kaffee, Mandeln, Ananas, Käse, Walnüsse, Vanillepudding, Bananen, Tomaten und Milchschokolade. Außerdem wurde der Einfluß des Zigarettenrauchens auf die Bestimmung von AD, NA, VMS und MN untersucht.Walnüsse führten zu einer starken Erhöhung der 5-HIE-Ausscheidung. Bananen erhöhten die Ausscheidung von AD, NA, VMS, MN und 5-HIE. Kaffee und Ananas bewirkten eine geringe Zunahme der MN-Werte. Rauchen von 20–30 Zigaretten/Tag beeinflußte keine der vier Variablen.Wenn die beschriebenen Methoden benutzt werden, sollte lediglich auf den Verzehr von Bananen und Walnüssen vor und während der Harnsammelperioden verzichtet werden, da die oberen Normgrenzen im Harn überschritten werden könnten. Ein Verzicht auf Kaffee und Ananas in normalen Mengen ist nicht erforderlich. Es besteht kein Anlaß, weiterhin die bisherigen umfangreichen Restriktionen der übrigen Nahrungsmittel beizubehalten. 相似文献