首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
Doklady Biochemistry and Biophysics - Common disadvantages of modern synthetic vascular prostheses are thrombogenicity and lack of biomechanical compatibility with the prothesized vessel. To...  相似文献   

2.
Chudinov  V. S.  Shardakov  I. N.  Litvinov  V. V.  Friend  G. G.  Solodnikov  S. Yu.  Maslova  V. V. 《Biophysics》2022,67(6):1011-1016
Biophysics - Vascular prosthesis samples were synthesized from polyurethane based on polypropylene glycol terminated with 2,4-toluylenediisocyanate. The outer and inner surfaces of the implants...  相似文献   

3.
Ongoing clinical studies on patients recently implanted with the auditory midbrain implant (AMI) into the inferior colliculus (IC) for hearing restoration have shown that these patients do not achieve performance levels comparable to cochlear implant patients. The AMI consists of a single-shank array (20 electrodes) for stimulation along the tonotopic axis of the IC. Recent findings suggest that one major limitation in AMI performance is the inability to sufficiently activate neurons across the three-dimensional (3-D) IC. Unfortunately, there are no currently available 3-D array technologies that can be used for clinical applications. More recently, there has been a new initiative by the European Commission to fund and develop 3-D chronic electrode arrays for science and clinical applications through the NeuroProbes project that can overcome the bulkiness and limited 3-D configurations of currently available array technologies. As part of the NeuroProbes initiative, we investigated whether their new array technology could be potentially used for future AMI patients. Since the NeuroProbes technology had not yet been tested for electrical stimulation in an in vivo animal preparation, we performed experiments in ketamine-anesthetized guinea pigs in which we inserted and stimulated a NeuroProbes array within the IC and recorded the corresponding neural activation within the auditory cortex. We used 2-D arrays for this initial feasibility study since they were already available and were sufficient to access the IC and also demonstrate effective activation of the central auditory system. Based on these encouraging results and the ability to develop customized 3-D arrays with the NeuroProbes technology, we can further investigate different stimulation patterns across the ICC to improve AMI performance.  相似文献   

4.
5.
Biophysics - The goal of this study was to assess the patency rate for a reinforced vascular bioprosthesis with KemAngioProsthesis xenogenic cells (JSC NeoСor, Kemerovo) during its mechanical...  相似文献   

6.
Traditionally, prosthetic leg research has focused on improving mobility for activities of daily living. Artistic expression such as dance, however, is not a common research topic and consequently prosthetic technology for dance has been severely limited for the disabled. This work focuses on investigating the ankle joint kinetics and kinematics during a Latin-American dance to provide unique motor options for disabled individuals beyond those of daily living. The objective of this study was to develop a control system for a bionic ankle prosthesis that outperforms conventional prostheses when dancing the rumba. The biomechanics of the ankle joint of a non-amputee, professional dancer were acquired for the development of the bionic control system. Subsequently, a professional dancer who received a traumatic transtibial amputation in April 2013 tested the bionic dance prosthesis and a conventional, passive prosthesis for comparison. The ability to provide similar torque-angle behavior of the biological ankle was assessed to quantify the biological realism of the prostheses. The bionic dancing prosthesis overlapped with 37 ± 6% of the non-amputee ankle torque and ankle angle data, compared to 26 ± 2% for the conventional, passive prosthesis, a statistically greater overlap (p = 0.01). This study lays the foundation for quantifying unique, expressive activity modes currently unavailable to individuals with disabilities. Future work will focus on an expansion of the methods and types of dance investigated in this work.  相似文献   

7.
8.
An apparatus for the preparation of uniform thin layer chromatography gel layers is described. The apparatus employs rubber cushion runners to compensate for differences in plate thickness and a gel applicator which functions independently of plate edge variability. Consistently uniform layers are prepared by careful establishment of the plate-to-applicator distance. Silica gel layers averaged 87% of the applied thickness with a variability of ±2% within a single run and ±8% between independent runs.  相似文献   

9.
10.
介绍了治疗皮肤病的新型纯中药制剂的配药比例.生产方法及成品检验标准。  相似文献   

11.
新型复合血管制备过程中胶原管成熟过程的观察   总被引:2,自引:0,他引:2  
本文对新型生物-人工复合血管制备过程中胶原管的成熟过程进行了观察,确定了成熟时间为3个月。作者发现胶原管的成熟过程是聚酯网和硅胶棒刺激增生的纤维结缔组织在聚酯周围及内侧围绕硅胶棒不断塑开始以细胞成分为主,以后随着胶原成分不断增多,到3个月时以胶原成分为主,胶原纤维变得粗大且有序,以聚酯为骨架的胶原管成熟。  相似文献   

12.
血管平滑肌细胞(vascular smooth muscle cell,VSMC)表型转化是血管损伤性疾病动脉粥样硬化、高血压和血管成形术后再狭窄等的共同病理生理过程.平滑肌22 alpha (smooth muscle 22 alpha, SM22α) 是一种VSMC分化标志物,其表达具有平滑肌组织特异性和细胞表型特异性. 该蛋白不仅作为一种肌动蛋白细胞骨架相关蛋白参与VSMC骨架组构和收缩调节,它还参与VSMC的增殖、炎症和氧化应激等进程. 本文就SM22α 的结构特征及其在VSMC血管损伤中的作用机制进行综述.  相似文献   

13.
14.
A new chloroxylenol preparation (DC) containing ethylenediamine tetraacetic acid (EDTA). has been shown to be an effective bactericidal agent against various Gram positive and Gram negative bacteria. It possessed significant and rapid activity against two strains of Pseudomonas aeruginosa as well as against chlorhexidine-and chloroxylenol-resistant derivatives of these strains. DC showed high activity at 20° and 30 °C, and (unlike chlorhexidine) when prepared in hard water or when used in the presence of organic matter. Repeated challenge testing at 20 °C of DC (but not of chloroxylenol) with Ps. aeuruginosa indicated that contamination of DC will not prove to be a problem in practice and that the activity of solutions will be retained during storage.  相似文献   

15.
桩核冠是临床上保存残根残冠的修复方法之一,按种类可分为金属桩和非金属桩两大类。影响桩冠固位的因素很多,主要包括核的材料、桩的表面形态、长度、直径、箍结构、粘结剂、桩核预备时机及桩在牙列中的位置。只有掌握了这些内容,恰当的选择和利用,才能保证临床修复效果。  相似文献   

16.
Retinal visual prostheses (“bionic eyes”) have the potential to restore vision to blind or profoundly vision-impaired patients. The medical bionic technology used to design, manufacture and implant such prostheses is still in its relative infancy, with various technologies and surgical approaches being evaluated. We hypothesised that a suprachoroidal implant location (between the sclera and choroid of the eye) would provide significant surgical and safety benefits for patients, allowing them to maintain preoperative residual vision as well as gaining prosthetic vision input from the device. This report details the first-in-human Phase 1 trial to investigate the use of retinal implants in the suprachoroidal space in three human subjects with end-stage retinitis pigmentosa. The success of the suprachoroidal surgical approach and its associated safety benefits, coupled with twelve-month post-operative efficacy data, holds promise for the field of vision restoration.

Trial Registration

Clinicaltrials.gov NCT01603576  相似文献   

17.
内膜增生是血管损伤后动脉重塑过程中普遍存在的现象。血管平滑肌细胞(vascular smooth muscle cells,VSMCs)的增殖、迁移、表型转换是血管损伤性疾病高血压、动脉粥样硬化、血管成形术后再狭窄等的共同病理生理学过程。干扰素调节因子(interferon regulatory factors,IRFs)是一类能对干扰素基因表达起到免疫调节作用的转录因子。近来研究发现,其在血管损伤病理过程具有调节作用,其中IRF1与细胞生长、分化和损伤密切相关,IRF3与IRF7可以抑制新生内膜的形成,而IRF8和IRF9则促进VSMCs增殖、迁移及血管内膜增生。本文重点介绍了IRFs的结构特征、信号途径及在血管重塑过程中作为新型调控因子的功能。  相似文献   

18.
本研究首次发现西藏新记录属云实属(Caesalpinia Linn.)植物——见血飞(Caesalpinia cucullata Roxb.),另外报道了11个新记录种和2个变种:瓶尔小草科(Ophioglossaceae)薄叶阴地蕨(Botrychium daucifolium Wall.),凤尾蕨科(Pteridaceae)华中凤尾蕨(Pteris kiuschiuensis var.centrochinensis ChingS.H.Wu),毛茛科(Ranunculaceae)尾叶铁线莲(Clematis urophylla Franch.),椴树科(Tiliaceae)刺蒴麻(Triumfetta rhomboidea Jacq.),锦葵科(Malvaceae)拔毒散(Sida szechuensis Matsuda),中华地桃花[Urena lobata var.chinensis(Osbeck)S.Y.Hu],柳叶菜科(Onagraceae)草龙[Ludwigia hyssopifolia(G.Don)Exell]、卵叶丁香蓼(Ludwigia ovalis Miq.),唇形科(Lamiaceae)小鱼仙草[Mosla dianthera(Buch.-Ham.)Maxim.],玄参科(Scrophulariaceae)石龙尾[Limnophila sessiliflora(Vahl)Bl.],爵床科(Acanthaceae)白接骨[Asystasia neesiana(Wall.)Nees],桔梗科(Campanulaceae)卵叶半边莲(Lobelia zeylanica Linn.),天南星科(Araceae)百足藤[Pothos repens(Loureiro)Druce]。研究结果进一步丰富了西藏的植物区系,并为研究与相邻地区植物区系的联系增加了新内容。  相似文献   

19.
目的研发了髋关节假体脱位分析软件。软件基于ADAMS/VIEW软件进行二次开发,能够可视化的构建三维参数化的髋关节假体模型,模型能够模拟假体的六种运动。应用此软件可以为病人更好的选择和植入假体,评估各种髋关节假体的安全活动范围,用来设计新的关节假体。  相似文献   

20.
Sperm are the most diverse cell type known: varying not only among- and within- species, but also among- and within-ejaculates of a single male. Recently, the causes and consequences of variability in sperm phenotypes have received much attention, but the importance of within-ejaculate variability remains largely unknown. Correlative evidence suggests that reduced within-ejaculate variation in sperm phenotype increases a male’s fertilization success in competitive conditions; but the transgenerational consequences of within-ejaculate variation in sperm phenotype remain relatively unexplored. Here we examine the relationship between sperm longevity and offspring performance in a marine invertebrate with external fertilization, Styela plicata. Offspring sired by longer-lived sperm had higher performance compared to offspring sired by freshly-extracted sperm of the same ejaculate, both in the laboratory and the field. This indicates that within-ejaculate differences in sperm longevity can influence offspring fitness – a source of variability in offspring phenotypes that has not previously been considered. Links between sperm phenotype and offspring performance may constrain responses to selection on either sperm or offspring traits, with broad ecological and evolutionary implications.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号