Biomaterials, artificial cells, and artificial organs最新文献_第9页

Segmental neogenesis of the dog esophagus utilizing a biodegradable polymer framework. 利用可生物降解聚合物框架的犬食道节段性新生。

Biomaterials, artificial cells, and artificial organs Pub Date : 1989-01-01 DOI: 10.3109/10731198909118286

M F Grower, E A Russell, D E Cutright

{"title":"Segmental neogenesis of the dog esophagus utilizing a biodegradable polymer framework.","authors":"M F Grower, E A Russell, D E Cutright","doi":"10.3109/10731198909118286","DOIUrl":"https://doi.org/10.3109/10731198909118286","url":null,"abstract":"This study evaluated the ability of biodegradable implants fabricated from polymers and co-polymers of polylactic acid (PLA) and polyglycolic acid (PGA) to induce regeneration of surgically created defects in the dog esophagus. The study utilized 12 mongrel dogs that had a 5 cm segment of the esophagus removed. Implants were fabricated by spray casting the polymers on a spinning Teflon mandril. The defects were repaired by suturing the biodegradable implants to the proximal and distal ends of the esophagus. Ten of the dogs were sacrificed from 3 days to 8 weeks after surgery while 1 of the dogs died after 3 years and 1 dog was sacrificed 4 years after graft placement. Endoscopic and histologic examination of the grafts 3 days after placement showed minimal inflammatory response and an apparent seal between the esophagus and implant at the suture lines. Two weeks after surgery a fibrous connective tissue sheath, continuous with the proximal and distal segments of the esophagus, could be seen surrounding the graft. One month after placement, the implants were partially degraded leaving a connective tissue repair continuous with the proximal and distal ends of the esophagus. The repair area was lined with epithelium and enabled the dogs to drink freely and eat semisolid foods. In conclusion, it has been shown that it is possible to fabricate a biodegradable implant which can stimulate regeneration of a hollow organ and which is compatible with long term survival.","PeriodicalId":77498,"journal":{"name":"Biomaterials, artificial cells, and artificial organs","volume":"17 3","pages":"291-314"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3109/10731198909118286","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13697890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 7

Immobilization of P. pictorum in open pore agar, alginate and polylysine-alginate microcapsules for serum cholesterol depletion. pictorum在开孔琼脂、海藻酸盐和聚赖氨酸-海藻酸盐微胶囊中的固定化用于血清胆固醇消耗。

Biomaterials, artificial cells, and artificial organs Pub Date : 1989-01-01 DOI: 10.3109/10731198909118285

F A Garofalo, T M Chang

引用次数: 14

Oxidative interactions between hemoglobin and egg lecithin liposomes. 血红蛋白与卵磷脂脂质体之间的氧化相互作用。

Biomaterials, artificial cells, and artificial organs Pub Date : 1989-01-01 DOI: 10.3109/10731198909117637

W S Pietrzak, I F Miller

引用次数: 9

Design for an ultrasound-based instrument for measurement of tissue blood flow. 一种基于超声波的组织血流量测量仪器的设计。

Biomaterials, artificial cells, and artificial organs Pub Date : 1989-01-01 DOI: 10.3109/10731198909118269

S M Burns, M H Reid

{"title":"Design for an ultrasound-based instrument for measurement of tissue blood flow.","authors":"S M Burns, M H Reid","doi":"10.3109/10731198909118269","DOIUrl":"https://doi.org/10.3109/10731198909118269","url":null,"abstract":"Quantitative measurement of tissue blood flow is of importance for many reasons: detection of capillary flow disturbances, evaluating indications for amputation, investigating vasospastic conditions, and evaluating vasoactive drugs or the effect of sympathectomy. Methods of investigating tissue blood flows include skin thermometry, thermal conductance or clearance, transcutaneous PO2, laser doppler flux, and photoplethysmographic techniques. A major reason that ultrasound has not previously been applied to this problem is that at the very low blood velocities in the capillaries (0.1 to 1 mm/sec) the Doppler shift is small (on the order of 1 Hz/MHz of carrier signal). Advantages of ultrasound are a noninvasive procedure and penetration depths greater than that possible with optical techniques. This paper discusses the development of a Doppler ultrasound instrument which allows spectral resolution of the velocities in tissue blood flow. Briefly, a low phase noise oscillator at 7.5 Mhz is used with two transducers to obtain the shifted signal. After mixing with the fundamental, the resulting low frequency signal is fed into a high resolution spectrum analyzer for analysis.","PeriodicalId":77498,"journal":{"name":"Biomaterials, artificial cells, and artificial organs","volume":"17 1","pages":"61-8"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3109/10731198909118269","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13813833","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 11

Polymer resins with amino acid containing pendants for sorption of bilirubin. IV. Site binding constants. 含有氨基酸的聚合物树脂吸附胆红素。IV.位点绑定常量。

Biomaterials, artificial cells, and artificial organs Pub Date : 1989-01-01 DOI: 10.3109/10731198909118275

S D Clas, D S Henning, G R Brown, L E St-Pierre

引用次数: 8

Hydrodynamic instability of "stroma-free" hemoglobin. “无基质”血红蛋白的流体动力学不稳定性。

Biomaterials, artificial cells, and artificial organs Pub Date : 1989-01-01 DOI: 10.3109/10731198909118289

T I Pristoupil, M Kramlová, T Marík

引用次数: 0

International Symposium on Red Cell Substitutes. 16-19 May 1989, San Francisco, California. Abstracts. 国际红细胞替代品研讨会，1989年5月16-19日，旧金山，加利福尼亚。摘要。

Biomaterials, artificial cells, and artificial organs Pub Date : 1989-01-01

引用次数: 0

Stress analysis of a total hip acetabular component: an FEM study. 全髋臼构件的应力分析:有限元研究。

Biomaterials, artificial cells, and artificial organs Pub Date : 1989-01-01 DOI: 10.3109/10731198909118852

D S Burton, H B Skinner, M Eng

{"title":"Stress analysis of a total hip acetabular component: an FEM study.","authors":"D S Burton, H B Skinner, M Eng","doi":"10.3109/10731198909118852","DOIUrl":"https://doi.org/10.3109/10731198909118852","url":null,"abstract":"A stress analysis of a total hip acetabular component was performed using three-dimensional finite element modeling. The model consisted of 548 four-noded quadrilateral shell elements with 582 nodes. A worst-case support condition was assumed in which bony contact with small areas of the ilium, ischium, and pubis was represented by three-point support. Loads corresponding to the peak pressures developed in the hip when rising from a seated position--the activity contributing most to the fatigue of a prosthesis--were applied to the model. Peak stresses of 490 MPa are predicted around a screw hole in the region of greatest loading; according to the fatigue curve for porous-coated Ti-6Al-4V alloy, this translates into a component life of three years. When the area of bony support for the prosthesis is increased by a factor of 1.5, the fatigue life is more than doubled to seven years. The addition of restraints around the loaded hole to represent the placement of a screw extends the lifetime dramatically to 65 years. Substituting the material properties of cobalt-chromium alloy increases the predicted lifetime of the component to twelve years. We conclude that poor bone support can compromise the service life of titanium alloy acetabular components. Furthermore, we suggest that screw fixation be used to secure the prosthesis in the anterior-superior region if the prosthesis is not well supported by bone in the acetabulum.","PeriodicalId":77498,"journal":{"name":"Biomaterials, artificial cells, and artificial organs","volume":"17 4","pages":"371-83"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3109/10731198909118852","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13748274","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Bunched and dispersed carbon fiber adsorbents for dextoxication. 聚束和分散的碳纤维吸附剂。

Biomaterials, artificial cells, and artificial organs Pub Date : 1989-01-01 DOI: 10.3109/10731198909118264

L I Fridman

引用次数: 0

Life forms protectable as subjects of U.S. patents -- microbes to animals (perhaps). 生命形式作为美国专利的保护对象——微生物到动物(也许)。

Biomaterials, artificial cells, and artificial organs Pub Date : 1989-01-01 DOI: 10.3109/10731198909118281

D S Hodgins

{"title":"Life forms protectable as subjects of U.S. patents -- microbes to animals (perhaps).","authors":"D S Hodgins","doi":"10.3109/10731198909118281","DOIUrl":"https://doi.org/10.3109/10731198909118281","url":null,"abstract":"Scientists, businessmen, universities and industries with fundamental or peripheral interests in technology as applied to life processes will be keenly interested in recent U.S. Patent Office decisions. These decisions indicate that new higher life forms, animal or plant, are proper subjects of patents if they are not naturally occurring (and are not human in the case of animals). In contrast to plants and other organisms, genetically modified animals have had no mode of protection as intellectual property except possibly as a trade secret or utility patent. The Ex parte Allen decision, reached by the Patent Office Board of Appeals and Interferences, directly addressed the issue of animal patentability in view of the broad reading of 35 U.S.C. section 101 by the U.S. Supreme Court in the Chakrabarty decision. The subject invention concerned polyploid oysters. Claims directed toward polyploid oysters produced by a particular process were rejected under 35 U.S.C. section 103 and section 101. The Board, reversing the 35 U.S.C. section 101 - based rejection in view of the Chakrabarty decision, indicated that the claimed polyploid oysters were non-naturally occurring manufactures or compositions of matter within the confines of patentable subject matter under 35 U.S.C. section 101. A similar decision affecting the patentable status of plants or segments thereof had previously been reached by the Patent and Trademark Office in the case of Ex parte Hibberd, 227 U.S.P.Q. 443 (Bd. Pat. App. 1985). The Hibberd utility patent application concerned \"genetically engineered\" maize which had high levels of the tryptophan.","PeriodicalId":77498,"journal":{"name":"Biomaterials, artificial cells, and artificial organs","volume":"17 2","pages":"205-24"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3109/10731198909118281","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13916060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1