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1.
生物玻璃-纳米羟基磷灰石梯度涂层的生物相容性研究   总被引:1,自引:0,他引:1  
目的 对生物玻璃-纳米羟基磷灰石(BG-nHA)梯度涂层的生物相容性作初步的评价.方法 用低温烧结法在钛合金表面制备生物玻璃纳米羟基磷灰石梯度涂层,利用L929细胞检测梯度涂层材料的细胞毒性.取体外分离培养扩增的人骨髓基质干细胞(hBMSC),接种于涂层材料上,通过绿色荧光蛋白染色、扫描电镜和MTT法观察细胞的黏附和生长情况.结果 生物玻璃-纳米羟基磷灰石梯度涂层的细胞毒性分级为1级,人骨髓基质干细胞可以在涂层材料表面黏附和生长.结论 生物玻璃-纳米羟基磷灰石梯度涂层有良好的生物相容性,具有潜在的临床应用前景.  相似文献   

2.
生物玻璃-纳米羟基磷灰石梯度涂层的生物相容性研究   总被引:2,自引:0,他引:2  
目的对生物玻璃-纳米羟基磷灰石(BG-nHA)梯度涂层的生物相容性作初步的评价。方法用低温烧结法在钛合金表面制备生物玻璃纳米羟基磷灰石梯度涂层,利用L929细胞检测梯度涂层材料的细胞毒性。取体外分离培养扩增的人骨髓基质干细胞(hBMSC),接种于涂层材料上,通过绿色荧光蛋白染色、扫描电镜和MTT法观察细胞的黏附和生长情况。结果生物玻璃-纳米羟基磷灰石梯度涂层的细胞毒性分级为1级,人骨髓基质干细胞可以在涂层材料表面黏附和生长。结论生物玻璃-纳米羟基磷灰石梯度涂层有良好的生物相容性,具有潜在的临床应用前景。  相似文献   

3.
声明     
在贵刊发表的《钛合金表面新型生物玻璃羟基磷灰石涂层的体内动物实验》(2008年第一期(第五卷第一期总第二十六期))和《钛合金表面新型生物玻璃/纳米羟基磷灰石涂层的细胞相容性评价》(2007年第五期(第四卷第五期总第二十四期),由于存在知识产权归属问题,现声明作废;并对由此给贵刊和上海交通大学附属第九人民医院造成的影响和不便表示谦意。  相似文献   

4.
目的为促进钛合金植入体与骨的结合,在其表面制备了生物玻璃/羟基磷灰石复合涂层,并植入兔子股骨内进行动物试验,采用等离子喷涂羟基磷灰石涂层和未涂层的Ti6Al4V合金作为对照。方法种植到期的植入体取出后进行组织学切片,采用品红-苦味酸染色后进行组织学观察,采用SEM高倍观察种植体与骨的结合界面,并对骨接触率和凹槽内骨长入量进行了统计分析和比较。结果三种植入体都具有良好的生物相容性。Ti6Al4V合金与骨之间是一种形态固定,而生物玻璃/羟基磷灰石涂层、等离子喷涂羟基磷灰石涂层可与骨形成骨键合。生物玻璃/羟基磷灰石涂层在植入期间与基体没有脱落,同时其与骨的接触率和凹槽内骨长入量要明显高于其余两个植入体,显示出促进骨生长的作用。结论由于具有良好的生物相容性和促进新骨生长的能力,生物玻璃/羟基磷灰石涂层可加快植入体与骨的愈合速度,在骨替代修复方面显示出优势和广阔的应用前景。  相似文献   

5.
背景:钛合金人工颈椎间盘具有良好的生物相容性,但钛合金存在生物活性差、与骨结合强度低、在生理环境下易造成金属离子释放等问题。目的:观察国产人工颈椎间盘钛合金终板不同涂层对大鼠骨髓间充质干细胞黏附、分化的影响。方法:将第3代Wistar大鼠骨髓间充质干细胞,接种于含羟基磷灰石涂层、钛粉复合羟基磷灰石涂层的钛合金板及裸钛合金板的24孔板内,培养的第24,48小时后分别终止培养,扫描电镜观察细胞生长情况;接种24 h后加成骨诱导剂进行诱导,并于第3,5,7天各收集细胞裂解后离心的上清,检测碱性磷酸酶表达。结果与结论:骨髓间充质干细胞与材料复合培养48 h后,羟基磷灰石组和钛粉复合羟基磷灰石组表面的细胞呈多角形,并伸出细长伪足伸入到材料的微孔内,与材料表面紧密黏附;而裸钛合金组骨髓间充质干细胞分化较差且黏附率低。随时间延长,各组碱性磷酸酶表达均增加,羟基磷灰石组和钛粉复合羟基磷灰石组各时间点的碱性磷酸酶表达均较裸钛合金组明显增高(P0.05)。表明羟基磷灰石、钛粉复合羟基磷灰石涂层可有促进大鼠骨髓间充质干细胞的黏附和分化。  相似文献   

6.
羟基磷灰石涂层钛合金材料生物相容性研究初探   总被引:1,自引:0,他引:1  
目的探讨一种新型的代骨材料--羟基磷灰石涂层的钛合金材料的生物相容性。方法制备羟基磷灰石涂层钛合金材料浸提液后,采用细胞毒性实验以观察实验样品浸提液对L929小鼠成纤维细胞的毒性反应;通过对小鼠尾静脉及腹腔注射试验样品浸提液后,观察其对小鼠的急性全身毒性反应;Ames实验及迟发型超敏反应实验对其遗传毒性及致敏性进行安全性评价。结果羟基磷灰石涂层钛合金材料浸提液对L929小鼠成纤维细胞的相对增殖率(RGR)为96.9%,细胞毒性反应为1级,无细胞毒性反应;对小鼠亦无明显的急性全身毒性作用,实验样品组与阴性对照组动物体质量差异无统计学意义(P0.05);遗传毒性Ames实验表明,在活化与非活化条件下,该材料浸提液对鼠伤寒沙门氏菌株的回变菌落数与对照组比均未增加2倍,对该菌株无诱变性;迟发型超敏反应实验显示,该材料浸提液无潜在的皮肤接触致敏性。结论羟基磷灰石涂层的钛合金材料具有良好的生物相容性。  相似文献   

7.
背景:低温快速成型技术具有支架成型可控性、保持材料生物学活性和易于实现支架材料的三维多孔立体结构等优势,被迅速用于骨组织工程支架的制备。目的:采用低温快速成型制备聚乙二醇改性聚乳酸-乙醇酸/纳米羟基磷灰石复合支架,并检测其性能。方法:采用低温快速成型设备分别制备聚乙二醇改性聚乳酸-乙醇酸/纳米羟基磷灰石与聚乳酸-乙醇酸/纳米羟基磷灰石复合支架,通过电镜观察支架超微结构,以介质(乙醇)浸泡法测定支架孔隙率,采用电子试验机检测支架力学性能;将两种支架材料分别与大鼠成骨细胞共培养,培养12 h采用沉淀法检测细胞黏附率,培养1,3,5,7,9,12 d采用CCK-8法检测细胞增殖。结果与结论:两组支架孔径均在理想范围内并具有较高孔隙率,但聚乙二醇改性聚乳酸-乙醇酸/纳米羟基磷灰石支架的孔径波动范围大,孔径均值较聚乳酸-乙醇酸/纳米羟基磷灰石支架小且部分有闭塞现象。聚乙二醇改性聚乳酸-乙醇酸/纳米羟基磷灰石支架的细胞黏附率及表面细胞增殖活性高于聚乳酸-乙醇酸/纳米羟基磷灰石支架(P0.05),力学性能低于聚乳酸-乙醇酸/纳米羟基磷灰石支架(P0.05)。表明聚乙二醇改性聚乳酸-乙醇酸/纳米羟基磷灰石复合支架具有良好的细胞相容性。  相似文献   

8.
羟基磷灰石作为天然骨的无机组分,是良好的生物陶瓷材料,被广泛应用于惰性支架的表面改良.但在天然骨中,羟基磷灰石往往掺杂了众多离子,而这些离子对骨的新陈代谢起着一系列的作用.研究表明,离子掺杂可以有效地提高羟基磷灰石涂层的生物相容性与功能性,进而增强植入材料与骨的结合,促进周边骨组织的生长.概述了离子掺杂羟基磷灰石涂层的研究现状,并分别叙述了阳离子镁、锶、锌、锰、铜、银及阴离子硅酸根、碳酸根、氟的掺杂对于羟基磷灰石涂层的影响,对离子掺杂羟基磷灰石涂层的发展方向进行了展望.  相似文献   

9.
背景:骨科植入材料表面改性可以减少或避免细菌黏附,利用金属表面的特殊涂层释放抑菌及杀菌成分可以预防骨科术后感染。目的:选择不同的制备参数,在医用纯钛表面沉积羟基磷灰石/纳米银复合涂层,观测复合材料表面银离子在模拟体液中的缓释性能。方法:利用脉冲电化学方法,在含银、钙、磷离子的溶液中实现纳米银和羟基磷灰石在钛表面的共沉积,再高温烧结处理制得复合涂层钛材料,用扫描电镜、X射线衍射仪、能谱仪对其形貌、组成进行表征。将分别含有0.5,1 mmol/L银的复合涂层钛材料浸泡在模拟体液中,在不同的时间点用原子能吸收光谱法检测Ag+浓度。结果与结论:复合涂层是由纳米针状羟基磷灰石和点状的银颗粒相互交织成的网状结构,纳米银颗粒在涂层中均匀分布。高温处理后涂层变得致密,羟基磷灰石的晶化度提高,银颗粒在烧结后无团聚现象。在模拟体液中,第1-7天Ag+释放量最大,第7-30天Ag+释放量趋于稳定并维持有效抗菌浓度。含0.5 mmol/L银复合涂层钛材料在30 d时Ag+释放总量低于细胞毒性浓度,含1.0 mmol/L银复合涂层钛材料在30 d时Ag+释放总量接近细胞毒性浓度的临界值,因此含0.5 mmol/L银电解液制备的材料用于临床更安全可靠。  相似文献   

10.
在NaF和H3PO4水溶液体系中,电化学阳极氧化法在钛板表面形成一层结构规整有序的高密度TiO2纳米管阵列.随后模拟体液(SBF)浸泡沉积出磷灰石涂层.扫描电镜(SEM)观察TiO2纳米管的微观结构,以及生成的磷灰石的形貌,X射线衍射仪(XRD)分析了涂层的相组成,电化学工作站研究极化行为.试验结果表明:Ti金属表面制备的规整的TiO2管直径约100 nm左右.模拟体液浸泡试验表明二氧化钛纳米管上沉积了羟基磷灰石涂层.  相似文献   

11.
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   

12.
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   

13.
About 1900, modern food selection and processing caused widespread epidemics 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 panhypovitaminosis B, i.e., a mixture of substrate beriberi and substrate pellagra resembling vitamin beriberi and pellagra but exhibiting as even more diverse endemic 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 primates. 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.
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   

16.
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   

17.
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   

18.
There is a sharp difference in how one views TCR structure–function–behaviour dependent on whether its recognition of major histocompatibility complex‐encoded restriction elements (R) is germline selected or somatically generated. The generally accepted or Standard model is built on the assumption that recognition of R is by the V regions of the αβ TCR, which is not driven by allele specificity, whereas the competing model posits that recognition of R is allele‐specific. The establishing of allele‐specific recognition of R by the TCR would rule out the Standard model and clear the road to a consideration of a competing construct, the Tritope model. Here, the case for allele‐specific recognition (germline selected) is detailed making it obvious that the Standard model is untenable.  相似文献   

19.
Most bodily functions require the coordinated actions of complementary and supplementary paired muscle groups. Where this essential muscular cooperation is lacking, hollow organs may burst and others become literally screwed up, giving rise to many similar spastic diseases such as Torticollis, Twisted ovarian cyst, Torsion of the Testis, Volvulus of the intestines, Varicose Veins, Megacolon, Aortamegaly, Scoliosis, Erb's Palsy, Peyronie's Disease, Main-en-Griffe, Undescended Foot (Pes Cavus), Talipes, Strabismus. Spasm is “panenepidemic” and unclassified examples of Torsion Dystonia and Dyskinesia really are as common as debt and taxes.  相似文献   

20.
Zusammenfassung Die Lagerung des Körpers hat wesentlichen Einfluß auf die Balance der transkapillären Bewegung eiweißarmer Flüssigkeit, das heißt auf das Gesamt-Starling-Gleichgewicht im Kreislauf. Aufrichten aus der horizontalen Lage hat Hämokonzentration, Hinlegen Hämodilution zur Folge. Folglich beeinflußt Lageänderung das Blut- und Plasmavolumen und darüber hinaus Werte wie Eiweißkonzentration, Hämatokrit oder Hämoglobinkonzentration im Blut.In der vorliegenden Arbeit wird die Möglichkeit vorgestellt, mittels der Biegeschwingermethode durch Dichtemessungen an Kapillarblut und -plasma diese orthostatischen Einflüsse auf hämatologische Zustandsvariable zu quantifizieren und ihren zeitlichen Verlauf mit hoher Auflösung zu erfassen.Im Durchschnitt ergab sich infolge Aufrichten des Körpers (70°) aus der Horizontalen eine Verringerung des Plasmavolumens um 6,6% nach 10 und um 11,1% nach 30 min; Hinlegen bewirkte nach 10 min eine Erhöhung des Plasmavolumens um 6,5% und nach 30 min um 10,5%. Entsprechende Blutvolumenveränderungen zwischen 5 und 10% gingen auch aus den Blutdichteänderungen bei orthostatischen Reizen hervor.Eine wichtige praktische Konsequenz ist die Forderung nach Beachtung der Körperlage vor und während Blutabnahmen, vor allem bei Verlaufsmessungen hämatologischer Größen bei ein und demselben Patienten oder bei statistischen Vergleichen verschiedener Kollektive.Diese Arbeit wurde vom Fonds zur Förderung der Wissenschaftlichen Forschung unterstützt  相似文献   

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