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1.
摘要 背景:初期使用的胶原、聚乳酸等单组分诱导骨再生膜在诱导成骨的效率方面已逐渐暴露其缺陷,于是以胶原、聚乳酸等可吸收材料为载体,羟基磷灰石、纤维生长因子、骨形成蛋白等为填料的诱导骨再生膜成为国内外研究的重点。 目的:观察纳米羟基磷灰石复合胶原膜组织反应对诱导骨再生的适用性。 方法:将聚丙交酯乙交酯膜、胶原膜、纳米羟基磷灰石复合胶原膜光滑面和粗糙面分别植入大鼠皮下,于10,20,30, 45 d取出,采用苏木精-伊红染色法,依照纤维包膜定量、定性、界面定性和降解率等进行组织学评分,研究3种膜的组织反应和降解情况。 结果与结论:纳米羟基磷灰石复合胶原膜在各个观察时间均有散在的淋巴细胞,但未见明显的巨噬细胞。随着时间的延长,膜逐渐变小,钙化物随着植入时间的延长而增加。胶原膜组织反应轻微,45 d几乎完全降解。聚丙交酯乙交酯膜浸润增多,纤维包裹明显。结果提示纳米羟基磷灰石复合胶原膜具有良好的生物相容性和适度的降解性,适合引导骨组织再生的需要。 关键词:引导骨组织再生;纳米羟基磷灰石复合胶原膜;组织学评估;生物降解;聚丙交酯乙交酯 doi:10.3969/j.issn.1673-8225.2010.42.011  相似文献   
2.
目的利用聚己内酯-聚乙二醇-聚己内酯(PCL1250-PEG1500-PCL1250)两亲性聚合物温敏凝胶作为载体材料,构建疏水性抗肿瘤药物紫杉醇的载药体系。方法以辛酸亚锡为催化剂、聚乙二醇为引发剂,引发己内酯单体开环聚合,合成PCL1250-PEG1500-PCL1250三嵌段共聚物。通过核磁共振氢谱及凝胶渗透色谱对其组成、结构及分子量进行表征;制备不同凝胶浓度及初始载药量的载药温敏凝胶,并对其相转变性能、体外药物释放行为以及体内的生物降解性能进行考察。结果核磁共振及凝胶渗透色谱测定结果表明:合成的共聚物组成与初始投料比一致,符合设计的PCL1250-PEG1500-PCL1250嵌段聚合物结构;该凝胶在15%~30%浓度区间内,具备温敏性溶胶-凝胶相转变能力;该温敏凝胶对紫杉醇具有可控的药物缓释能力,通过改变凝胶浓度及初始载药量可凋节药物释放速率和维持释放的时间。小鼠背部皮下注射PCL1250-PEG1500-PCL1250溶胶后在体内迅速原位凝胶化,凝胶随植入时间逐渐降解至45d时基本降解完全。结论PCL1250-PEG1500-PCL1250温敏凝胶作为紫杉醇载药体系具有良好的药物控释能力和体内生物降解性能。  相似文献   
3.
New types of hydrophilic gels based on N-(2-hydroxypropyl)methacrylamide which contain oligopeptide sequences in the crosslinks were prepared. These gels are enzymatically degradable by chymotrypsin. The rate of their degradation may be varied within a broad range by changes in the length and detailestructure of the oligopeptide sequence in the crosslinks and by changing their network density.  相似文献   
4.
Bioreactions at the tissue/hydroxyapatite interface   总被引:2,自引:0,他引:2  
The events at the hydroxyapatite implant material/tissue interface in the rat middle ear were studied by light microscopy, autoradiography, morphometry, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and X-ray microanalysis. Deposition of calcium, partially in the form of calcium phosphate, was found at the interface. Resorption of the implant material occurred as the result of mono- and multinuclear phagocyte activity. Resorption decreased 6 mnth after the operation, possibly due to the decreasing number of phagocytes at the interface and the increasing amount of bone in the macropores.  相似文献   
5.
PURPOSE: A controlled-release drug delivery of contraceptive steroids levonorgestrel (LNG) and ethinyl estradiol (EE) has been developed by successful encapsulation of LNG and EE in poly (lactide-co-glycolide) (PLG) microspheres. MATERIALS AND METHODS: Smooth, spherical, steroid-loaded PLG microspheres with a mean size of 10-25 microm were prepared by using the water/oil/water double-emulsion solvent evaporation method. RESULTS: In vitro release profiles showed an increased burst release of LNG/EE on Week 1; thereafter, the release was sustained. At the end of Week 7, the release of LNG/EE from 1:5 and 1:10 PLG microspheres was 75.64% and 62.55%. respectively. In vitro degradation studies showed that the PLG microspheres maintained surface integrity up to Week 8 and then eroded completely by Week 20. In an in vivo study, the serum concentration of LNG/EE in rats showed a triphasic release response, with an initial burst release of 8 ng/mL LNG and 14 pg/mL EE on Day 1; thereafter, a controlled release of the drugs to the systemic circulation was maintained until Week 15, maintaining constant drug levels of 2 ng/mL LNG and 3-4 pg/mL EE in the blood. Histological examination of steroid-loaded PLG microspheres injected intramuscularly into the thigh muscle of Wistar rats showed minimal inflammatory reaction, demonstrating that contraceptive-steroid-loaded microspheres were biocompatible. CONCLUSION: This controlled-release and biocompatible nature of the PLG microspheres may have potential application in contraceptive therapy.  相似文献   
6.
目的:观察可吸收固定板和螺钉用于治疗颧眶部骨折及矫正面部畸形的临床效果。。方法:采用头皮冠状切口将可吸收固定板和螺钉用于颧眶部骨折内固定,术后随访6个月,观察此材料在人体内的组织相容性和是否有骨断端移位,并和钛钢板组对比,结果:术后随访6个月钛钢板和可吸收固定板组均未发现局部异物免疫排斥反应,骨折断端无移位,骨年愈合无正常。结论:可吸收的固定板和螺钉配合头皮冠状口用于颧眶部骨折能收良好的临床治疗效果。  相似文献   
7.

Background

A variety of materials have been used for bone augmentation, distraction osteotomy, and in post-cancer patients following tumor removal. However, a temporary metal implant that would resorb after successful treatment is a new concept. Magnesium was suggested as a suitable material for these purposes because it is biocompatible, has better mechanical properties than titanium, and stimulates new bone formation. This study evaluates histological appearance of magnesium-based implants and the surrounding bone.

Materials and Methods

Three magnesium-based biomaterials were tested in a rabbit bone defect model: magnesium–hydroxyapatite (Mg–HA), W4 (96 % magnesium, 4 % yttrium), and pure magnesium (pure Mg). Animals were sacrificed after 6 and 12 weeks and the samples were analyzed histologically and histomorphometrically.

Results

Mg–HA had the highest mean amount of tartrate-resistant acid phosphatase (TRAP) positive cells at the implantation site of all groups. It had shown the fastest degradation rate already at 6 weeks but the least amount of new bone formation. New bone was seen forming in direct contact with pure Mg and W4. The mean gas volume was highest in W4 compared to pure Mg and Mg–HA but this difference was not statistically significant. W4 had the lowest mean number of TRAP-positive cells of all materials.

Conclusion

Pure Mg and W4 were shown to be the most promising materials in this study in respect to the bone response to the implant material. They could be used for screws and plates in bone augmentation procedures.  相似文献   
8.
壳聚糖膜的降解性研究   总被引:11,自引:3,他引:8  
用不同性能地壳聚糖为膜材料制备壳聚糖膜,通过体外酸解,酶解试验及动物体内植入试验研究其降解。试验结果表明,壳聚糖是一种可生物降解性膜材料,壳聚糖膜的降解性与其脱乙酰度,介质酸性强弱及溶菌酶等因素有关。壳聚糖膜在动物体内降解比较缓慢,20天约降解8.2%。  相似文献   
9.
目的:用于组织工程化软骨、骨、脂肪等修复重建和整形用的可注射细胞支架.方法:以聚丙交酯(PLLA)、聚丙交酯/聚乙二醇共聚物(PLE),以及聚己内酯/聚乙二醇/聚丙交酯共聚物(PCEL)等聚内酯类生物降解高分子为基材,采用乳液-溶剂挥发法制成微米级大小、具有一定形态结构的微球.结果:聚内酯材料的组成对微球的形态结构有重要影响,微球的孔结构和稳定剂种类对微球的细胞亲和性有重要影响;含聚乙二醇成分的聚内酯材料可以形成呈多孔结构的微球,且以明胶为稳定剂制备的微球细胞亲和性更好.结论:聚内酯类生物降解高分子微球具有可注射性和良好的细胞亲和性,是一类具有应用前景的可注射细胞支架.  相似文献   
10.
壳聚糖膜生物降介与组织反应的实验研究   总被引:2,自引:0,他引:2  
本文就新型天然高分子壳聚糖制成膜植入小鼠股部肌肉内。按时处死,称量植入前后的重量以评价降解性,同时以外科缝合丝为对照,作组织相空性观察。结果表明,植入膜早期,组织处于慢性炎症反应期,16周时,膜已降解过半,组织学反应应与丝线对照组接近。壳聚糖膜虽然对机体产生一定反应,但随着壳聚糖的分解,其代谢产物对机体无明显副作用,可作为一种新型医用生物膜材料。  相似文献   
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