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1.
为解决传统人工胫骨平台假体个体匹配性差,结构强度与生物活性难统一等问题,提出了定制化复合增强型人工胫骨平台系统的设计制造方法。采用解剖学建模技术设计出外形匹配,内含三维网状构架的复合假体模型,利用快速成型技术制造出假体的树脂原型,并分别通过精密铸造和粉末烧结技术制造出钛合金胫骨平台和大段多孔陶瓷人工骨。结果显示,该方法能快速而精确地制造出形状复杂的人工胫骨平台系统,是实现假体定制化制造的有利保证;通过将金属假体和多孔陶瓷人工骨复合,解决了载重部位大段骨缺损的修复问题。临床应用表明,该假体能与对侧关节匹配运动,通过将机械重建与生物重建相结合可实现受损关节的功能重建。  相似文献   

2.
定制化单侧膝关节假体设计与快速制造方法研究   总被引:7,自引:0,他引:7  
目前人工假体的制造还难以达到个体适配化,尤其是带有关节面的半关节,能否与对侧正常关节软骨完全匹配是决定手术治疗成败的关键。本文以临床影像学资料为数据源,应用逆向工程和快速原型技术相结合制作出与人体膝关节面形状完全相匹配的人工假体原型,而后利用传统的制作工艺完成假体关节面及其连接结构的最终成型。结合异体骨移植术,将该项研究结果成功地用于股骨下段肿瘤患者,临床资料显示该假体能够与患者对侧关节面良好匹配,患者关节功能恢复较理想。该方法可实现替换关节面和对侧面的匹配,而且假体制造的周期短、成本低,可实现个体定制化,为探索半关节置换及临床提供了制造方面的技术保障。  相似文献   

3.
目的:观察钛表面纳米仿生磷灰石涂层对成骨样细胞行为的影响,为骨科常用钛植入体的表面改性及其生物效应提供实验依据。方法: 商业用纯钛经过物理、化学和生物处理,表面生成均匀薄层仿生的纳米磷灰石涂层,将仿生涂层的钛金属板与成骨样细胞复合培养,以纯钛和只经磨砂、酸蚀处理的钛板作为对照,采用MTT法检测细胞活力和增殖变化、扫描电镜和激光共聚焦荧光显微镜观察细胞形态、RT-PCR检测碱性磷酸酶基因表达。结果: 纳米仿生磷灰石涂层比非涂层钛金属表面细胞的增殖数量明显增高,细胞的形态和分布也优于对照组;培养12 d,涂层对细胞ALP基因表达的量明显高于对照组。结论: 钛金属表面纳米仿生磷灰石涂层可以增强细胞的生物效应,提高钛植入体的骨界面早期结合,具有很好的应用前景。  相似文献   

4.
背景:近年来,快速成型技术被迅速的应用于医学重建领域,利用快速成型技术可为组织缺损患者制作个体化的植入物,可达到空间尺寸上的精确修复。 目的:利用快速成型技术制作个体化钛板,结合自体松质骨移植,修复犬下颌骨节段性缺损。 方法:9只杂种犬行螺旋CT扫描获取头颅骨骼数据,建立数字3D模型,在模型上模拟右侧下颌骨体部切除术,并制作个体化板状修复体,经快速成型加工制造,获得个体化的钛板。然后行动物实验,手术制造右侧下颌骨体部4 cm长节段性缺损,同期手术切取自体髂骨块固定于快速成型钛板的舌侧,修复下颌骨缺损。采用核医学、力学、影像学和组织学等方法评估骨移植后的转归。 结果与结论:应用快速成型支架重建了左右对称的下颌骨形态,自体髂骨移植后逐渐皮质化,植骨和钛板之间形成纤维结缔组织间隔层。在下颌骨缺损修复中,应用快速成型钛板能够达到形态和功能兼顾的效果。 中国组织工程研究杂志出版内容重点:组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程全文链接:  相似文献   

5.
该文运用增材制造技术快速制备三维重建的缺损颅骨植入体,通过对骨植入体材料对比分析,选择多孔羟基磷灰石材料应用于颅骨植入手术中。运用Mimics 10.0软件对临床计算机断层扫描(CT)影像数据重建三维植人体模型,采用增材制造技术制备多孔羟基磷灰石颅骨植入体,与颅骨贴合度好,表面光滑平顺,而多孔羟基磷灰石能够引导和诱导骨的形成,大大提高其生物相容性。增材制造技术快速制备的特点促使个性化颅骨修补植入物成为可能,个性化医用三维模型用于植入手术降低手术风险,术后效果好,具有推广应用的前景。  相似文献   

6.
骨组织微结构观察分析及仿生支架立体光固化间接制造   总被引:5,自引:0,他引:5  
通过对骨组织显微结构观察分析,指导人工骨支架内部微管道结构设计,结合CAD、反求工程和快速成形技术制造仿生结构生物活性人工骨支架.观察骨组织切片,获取骨组织微观结构数据,进行三维重构和辅助设计,应用快速成形技术制造相应的支架模具.在模具中填充磷酸钙骨水泥,烧结后得到仿生结构生物活性人工骨支架.光学显微镜和扫描电镜观察和测量支架微结构,X射线衍射分析磷酸钙骨水泥在热分解前后的主要成分,结果表明,所得支架与设计相符,热分解前的磷酸钙骨水泥主要成分为低结晶度的羟基磷灰石,而热分解之后为结晶度更高的羟基磷灰石.体外培养试验表明支架无细胞毒性,且黏附在支架上的细胞保持着良好的形态和功能发挥.  相似文献   

7.
背景:颅颌面骨为不规则骨,具有复杂的三维立体结构。对于颅颌面的骨缺损,进行个性化精确修复十分重要。计算机辅助设计、计算机辅助制造和激光扫描技术是近年发展起来的高新技术,通过这些技术可以实现颅颌面个性化骨形态结构的三维仿真。 目的:设计一个由计算机辅助设计、计算机辅助制造和激光扫描技术组成的数字医学系统,以实现生物材料对下颌骨髁突等形态的三维模拟。 方法:通过CT扫描获得犬头颅影像信息,计算机辅助设计、计算机辅助制造实现下颌骨形态的三维重建影像,影像数据输入三维打印机,快速成型获得下颌骨髁突的树脂阳模。阴阳模转换获得相应石膏阴模,聚羟基乙酸/聚乳酸阴模内成型,激光三维表面扫描检测聚羟基乙酸/聚乳酸支架和影像原型匹配的精确度。 结果与结论:聚羟基乙酸/聚乳酸支架和影像原型匹配的精确度检测结果显示,当测试点误差小于1.0 mm时,复合率大于95%。提示通过这套数字医学系统,可实现颅颌面骨形态结构生物材料的三维仿真,为下颌骨骨缺损的精确修复打下基础。  相似文献   

8.
目的 探索利用水平集方法和快速原型技术得到颅骨缺损修复假体用于颅骨修复。方法 基于有颅骨缺损的患者的CT数据,利用水平集方法结合病人脑组织信息得到完整的颅骨原始轮廓,还原出颅骨缺损部位信息,三维重建后应用三维打印机进行定制的颅骨缺损修复假体的快速原型制造。结果 所得颅骨缺损修复假体非常适合颅骨缺损的部位,使用水平集方法和快速原型技术得到的颅骨缺损修复假体有很好的个体适配性。结论 水平集方法和快速原型技术精确制造颅骨缺损修复假体是可行的,对颅骨缺损修复手术提供术前规划、减少术中危害具有重要意义。  相似文献   

9.
提出了基于快速成形和生物医学技术的人工生物活性骨制造方法,能通过适当的材料和成型工艺制作出模拟真实骨骼内部组织的三维孔腔结构和内孔三维网状构架,并填入自固化磷酸钙骨水泥和生物活性因子到孔腔中来制备生物活性骨。本研究通过动物实验验证了植入骨的生物学性能,说明该方法有效可行,较好地实现了先进制造与生物活性的复合一体化。  相似文献   

10.
背景:预制个性化骨瓣具有创伤小、血运好、可带软组织、形状可定制等优点,可用来修复血管床欠佳的骨缺损。 目的:建立预制骨瓣修复灵长类下颌骨缺损的动物模型。 方法:对9只恒河猴进行头颅扫描并制作个性化钛网。将复合或者未复合人重组骨形态发生蛋白2的脱钙冻干骨、珊瑚装入个性化钛网,植入背阔肌中进行个性化、血管化组织工程骨瓣的预制或者原位植入下颌骨节段性缺损。13周时,个性化、血管化组织工程骨瓣预制成功,将其转移修复下颌骨节段型缺损。采用临床和组织学方法观察异位预制个性化骨瓣及原位植入人重组骨形态发生蛋白2修复下颌骨缺损的效果。 结果与结论:预制骨瓣和原位植入的复合人重组骨形态发生蛋白2的珊瑚能修复下颌骨节段性缺损;原位植入复合或未复合人重组骨形态发生蛋白2的脱钙冻干骨和单纯珊瑚不能修复下颌骨缺损。复合人重组骨形态发生蛋白2的脱钙冻干骨、珊瑚预制个性化、血管化组织工程骨瓣成功,转移后均能成功修复下颌骨缺损,而且修复下颌骨缺损的效果优于材料直接植入下颌骨缺损组。实验证实预制个性化骨瓣修复恒河猴下颌骨缺损模型是可行的。 中国组织工程研究杂志出版内容重点:肾移植;肝移植;移植;心脏移植;组织移植;皮肤移植;皮瓣移植;血管移植;器官移植;组织工程全文链接:  相似文献   

11.
Boll  Irene  Eisold  H.  Gaul  H. B.  Kehr  J.  Löchte  K. H.  Niemann  W.  Stender  K.  Stockhorst  H. U.  Suchy  B. R.  Szantho von Radnoth  B.  Taj  A.  Theuner  E.  Troester  P. M.  Werner  F.  Wilke  G.  Willigerodt  P. 《Journal of molecular medicine (Berlin, Germany)》1978,56(4):187-195
Zusammenfassung Die Beeinflussung der Erythroblasten-Proliferation durch das Mikromilieu wurde in vitro mittels Auswertung durch Differential- und Mitosezählungen und Signifikanzberechnung vieler Versuchsreihen auch unter verschiedenen pathologischen Bedingungen getestet.Sowohl die Mitosehäufigkeit wie die Ausreifung waren positiv mit dem Erythropoetingehalt des Medium korreliert. Der Effekt wurde durch Folsäure, Ätiocholanolon und cAMP verstärkt. Cobalt stimulierte ebenso wie Testosteron und Methenolon in vitro unabhängig von der Erythropoetinkonzentration im Medium die Erythroblastenproliferation. Ein vermindertes Eisenangebot störte die endgültige Ausreifung der Erythroblasten zu Retikulozyten und bewirkte dadurch eine Ineffektivität der Erythorpoese. Anhaltspunkte für ein Erythrozyten-Chalon oder einen Erythropoetinhemmkörper ließen sich aus unserem Versuchsansatz nicht gewinnen, weil er die Transformation der pluripotenten in die erythropoetin-sensible Stammzelle nicht einschließt. Als Nebenbefund ergab sich eine Stimulation des granulozytopoetischen Proliferationsspeichers durch Serumzusatz zum Medium von Patienten nach akutem Blutverlust und bei Polycythämia vera.Unterstützt durch die Deutsche Forschungsgemeinschaft  相似文献   

12.
《Human immunology》2020,81(6):265-266
Aymara people has been a relatively homogeneous group since Spanish Conquest by 1,532 CE, even if previously represented a group of various cultural defined populations who gave rise to them. They were and are established in Andean Altiplano around Titikaka Lake (Bolivia, Peru), Argentina and Chile neighborhood, speak Aymara language and have been maintained after Europeans arrival at a lower social status than Quechua (Inca) speaking people. However, both Aymara and Quechua populations acknowledge Titikaka Lake as center of their origins; both languages are also related. Specific high frequencies of HLA-A*02, -A*24 and -A*68, HLA-B*35, -B*39 and -B*48, HLA-DRB1*08:02, -DRB1*09:01, and -DRB1*14:02, and HLA-DQB1*04:02, -DQB1*03:02 and -DQB1*03:01 alleles are found in Aymaras and HLA class II haplotypes common to Andean Amerindians (DRB1*08:02-DQB1*04:02 and DRB1*04:03-DQB1*03:02), like Quechua, Aymara, Uros, Lamas and Mapuche are also found in Easter and other Pacific Islands. Giant human head stone statues at Tiwanaku (Titikaka Lake, Bolivia) are also found at Easter Island. Thus, it is possible a gene and cultural flow between Andean Amerindians and Easter and other Pacific Islands, as it was demonstrated by Thor Heyerdahl in his Kon-Tiki expedition which reached Pacific Islands sailing from El Callao Harbour (Lima, Peru).  相似文献   

13.
A lipid analysis was performed on developing metacestodes of Taenia taeniaeformis removed from the livers of rats at times varying from 3 to 35 weeks post infection. Lipid accounted for 7–21% of the dry weight of the parasites. The highest proportions were found at the earlier stages. The distribution was as follows; neutral lipid 27–45%; glycolipid 5–11%; and phospholipid 50–61%. The major neutral lipid was cholesterol, and minor neutral lipids were sterol esters, triglycerides, diglycerides and monoglycerides. Hydrocarbons were present throughout development, but in the highest amounts at the earlier stages. Five different glycolipids were found, all of which were identified as glycosphingolipids. An increase in the proportion of more complex glycolipids was noted as parasites grew older. Ten different phospholipids were identified, with the major components being phosphatidylcholine, phosphatidylethanolamine, and phosphatidylserine. Other phospholipids were: lysophosphatides, phosphatidylinositol, phosphatidic acid, diphosphatidylglycerol, sphingomyelin, and an unknown phospholipid component. Changes in the relative amounts of the two major phospholipids were found when the early and late stages were compared. Two lipids found throughout development were identified as glycosylated dolichol phosphates, and they comprised between 1 and 3% of the total phospholipid fraction. Nineteen fatty acids were detected, and the fatty acid distribution for each lipid class at each stage was determined. Seven major fatty acids were common to each. These were: hexadecanoic, octadecanoic, oleic, linoleic, arachidonic, docosanoic, and docosahexaenoic.  相似文献   

14.
An attempt was made to produce sensitive and specific polyclonal antisera against the viruses causing rice tungro disease, and to assess their potential for use in simple diagnostic tests. Using a multiple, sequential injection procedure, seven batches of polyclonal antisera against rice tungro bacilliform virus (RTBV) and rice tungro spherical virus (RTSV) were produced. These were characterized for their sensitivity and specificity using ring-interface precipitin test and double antibody sandwich (DAS) ELISA. Thirty-one weeks after the first immunization, antiserum batch B6b for RTBV showed the highest ring interface titer (DEP = 1:1920). For RTSV, batches S3, S4b and S5b all had similar titres (DEP = 1:640). In DAS-ELISA, however, significant differences among purified antisera (IgG) batches were observed only at IgG dilution of 10-3. At that dilution, IgGB4b showed the greatest sensitivity, while IgGS3 showed greatest sensitivity for RTSV. When all IgG batches were tested against 11 tungro field isolates (dual RTBV-RTSV infections) at sample dilution of 1:10, IgGB4b and IgGB6b for RTBV and IgGS3 and IgGS6b for RTSV performed equally well. However, after cross adsorption with healthy plant extracts in a specially prepared healthy plant-Sepharose affinity column, only IgGB6b could be used specifically to detect RTBV in a simple tissue-print assay.  相似文献   

15.
Nowadays, people pay more attention to biomarkers that can predict clinical efficacy of immunotherapy for allergic rhinitis. As the only recognized aetiological treatment, the efficacy of allergen immunotherapy (AIT) has been proved by many studies. However, treatment success depends on compliance and persistence greatly, which can be impaired by the lengthy duration of AIT and socioeconomic status of patients. Besides, ineffectiveness is another factor that accounts for non-adherence. If the clinical efficacy can be predicted in the early stage of immunotherapy, it can help patients choose appropriate treatment plans, increase patient compliance and optimize the allocation of medical resources. This paper mainly focuses on five candidate biomarkers, the sIgE/tIgE ratio before treatment, serum inhibitory activity for IgE, decreased basophil activation, upregulation of Tregs and tolerogenic DCs, reviews the time when potential biomarkers can predict or monitor the efficacy of AIT, discusses the reason why these indicators could serve as efficacy biomarkers and interactions among potential biomarkers.  相似文献   

16.
Neurotransmitters are not only involved in brain function but are also important signaling molecules for many diverse cell types. Neurotransmitters are widely conserved, from evolutionarily ancient organisms lacking nervous systems through man. Here, results are reported from a loss‐ and gain‐of‐function survey, using pharmacological modulators of several neurotransmitter pathways to examine possible roles for these pathways in normal embryogenesis. Applying reagents targeting the glutamatergic, adrenergic and dopaminergic pathways to embryos of Xenopus laevis from gastrulation to organogenesis stages, we observed and quantified numerous malformations, including craniofacial defects, hyperpigmentation, muscle mispatterning and miscoiling of the gut. These data implicate several key neurotransmitters in new embryonic patterning roles, reveal novel earlier stages for processes involved in eye development, suggest new targets for subsequent molecular‐genetic investigation, and highlight the necessity for in‐depth toxicology studies of psychoactive compounds to which human embryos might be exposed during pregnancy.  相似文献   

17.
18.
Uncombable hair syndrome was first described some 3 decades ago as "cheveux incoiffables" and is also known as spun-glass hair and pili trianguli et canaliculi. Both inherited (autosomal dominant and recessive with variable levels of penetrance) and sporadic forms of uncombable hair syndrome have been described, both being characterized by scalp hair that is impossible to comb due to the haphazard arrangement of the hair bundles. A characteristic morphologic feature of hair in this syndrome is a triangular to reniform to heart shape on cross-sections, and a groove, canal or flattening along the entire length of the hair in at least 50%of hairs examined by scanning electron microscopy. Most individuals are affected early in childhood and the hair takeson a spun-glassappearance with the hair becoming dry, curly, glossy, lighter in color, and progressively uncombable. Only the scalp hair is affected. Several conditions are associated with uncombable hair, such as ectodermal dysplasia, retinal dysplasia/ pigmentary dystrophy, juvenile cataract, digit abnormalities, tooth enamel anomalies, oligodontia, and phalangoepiphyseal dysplasia. Other syndromes with hair abnormalities may also mimic uncombable hair syndrome clinically and these include, Rapp-Hodgkin ectodermal dysplasia; loose anagen hair syndrome; ectodermal dysplasia, ectrodatyly, cleft lip/ palate (EEC) syndrome; and familial tricho-odonto-onchyial ectodermal dysplasia with syndactyly. Unlike other conditions with an uncombable hair component, uncombable hair syndrome alone (cheveux incoiffables, pili trianguli etcanaliculi) is not associated with physical, neurologic, or mental abnormalities. In most cases of uncombable hair syndrome, the hair is grossly abnormal in infancy and early childhood, but may have improved manageability later in life. Scanning electron microscopy of hair samples provides definitive evidence for diagnosis of clinically suspected uncombable hair syndrome and eliminates other hair abnormalities from the differential diagnosis.  相似文献   

19.
Synaptic structures in the neocortex and hippocampus of the intact brain were compared between rats with low and high resistance to hypobaric hypoxia. Activities of choline acetyltransferase, acetylcholinesterase, Na,K-ATPase, and the portion of protein in the light and heavy synaptosome fractions and subfractions were measured. A discrepancy in cholinergic metabolism molecular mechanisms between high and low resistance animals have been found in the heavy somatosoma fraction from the neocortex. Activities of choline acetyltransferase, acetylcholinesterase, and Na,K-ATPase in the synaptolemmal subfraction of low resistant rats were much lower than in high resistant rats. This implies a less effective synaptic transmission in proper cholinergic neurons in the low resistance animals and, therefore, specifically changed neuron functioning in the circulation control. No differences in the cholinergic components of either neocortical light synaptosome fraction or hippocampal light and heavy synaptosome fractions were found between low and high resistance rats. Translated fromByulleten' Eksperimental'noi Biologii I Meditsiny, Vol. 125, No. 5, pp. 521–525, May, 1998  相似文献   

20.
This guideline advises on the management of patients with cow's milk allergy. Cow's milk allergy presents in the first year of life with estimated population prevalence between 2% and 3%. The clinical manifestations of cow's milk allergy are very variable in type and severity making it the most difficult food allergy to diagnose. A careful age‐ and disease‐specific history with relevant allergy tests including detection of milk‐specific IgE (by skin prick test or serum assay), diagnostic elimination diet, and oral challenge will aid in diagnosis in most cases. Treatment is advice on cow's milk avoidance and suitable substitute milks. Cow's milk allergy often resolves. Reintroduction can be achieved by the graded exposure, either at home or supervised in hospital depending on severity, using a milk ladder. Where cow's milk allergy persists, novel treatment options may include oral tolerance induction, although most authors do not currently recommend it for routine clinical practice. Cow's milk allergy must be distinguished from primary lactose intolerance. This guideline was prepared by the Standards of Care Committee (SOCC) of the British Society for Allergy and Clinical Immunology (BSACI) and is intended for clinicians in secondary and tertiary care. The recommendations are evidence based, but where evidence is lacking the panel of experts in the committee reached consensus. Grades of recommendation are shown throughout. The document encompasses epidemiology, natural history, clinical presentations, diagnosis, and treatment.  相似文献   

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