摘要:

AbstractThe effect of wettability of 14 polypeptide derivatives upon adhesion and activation of platelets was investigated with reference to release reactions from adhered platelets, using radioisotope labeling and radio‐immunoassay method. The serotonin release was more significant from platelets adhered to polymer materials to which a large number of platelets are adhered. However, no clear relationship was found between adhesion of platelets and β‐thromboglobulin release from adhered platelets. Therefore, stimuli inducing serotonin release and β‐thromboglobulin release were considered to be from different origins. The trend in β‐thromboglobulin release was well correlated with the extent of morphological change of adhered platelets as observed by scanning electron microscope. It was suggested that the determination of released β‐thromboglobulin in association with the measurement of platelet adhesion could be useful for evaluation of blood compatibility

ISSN:0021-9304    

DOI:10.1002/jbm.820220702

出版商:John Wiley&Sons, Inc.    

年代:1988

数据来源: WILEY

摘要:

AbstractA new culture system was developed to clarify the biocompatibility of implant materials with bone tissue using the MC3T3‐E1 osteogenic cell line. The cells were inoculated onto specimens such as aluminium oxide, titanium, dental casting silverpalladium alloy (PD), and a plastic coverslip. To study the effects of these materials on cell growth, differentiation, and calcification, DNA and protein content, alkaline phosphatase activity, and calcium content, respectively, were determined. The results from biochemical analysis suggest titanium and aluminium oxide to have adequate biocompatibility, while PD has an irritant effect on cell metabolism. It is clear that an objective view of the differentiation and calcification processes of osteogenic cells can be understood through such analysis. From the results of this study, our culture system appears suitable for evaluating the biocompatibility of implant materials with bone tissu

ISSN:0021-9304    

DOI:10.1002/jbm.820220703

出版商:John Wiley&Sons, Inc.    

年代:1988

数据来源: WILEY

摘要:

AbstractThe formation and structure of zinc polyacrylate has been studied by Fourier transform infrared spectroscopy (FTIR). Using this technique we have shown that the fully hardened cement is bonded predominantly by zinc carboxylate complexes, rather than by associations of purely ionic character as had previously been supposed. Ionic bonds are formed in the initial stages of the reaction but are gradually converted to complex forms. This bond rearrangement appears partly responsible for physical changes that occur during gelation, setting, and hardening.

ISSN:0021-9304    

DOI:10.1002/jbm.820220704

出版商:John Wiley&Sons, Inc.    

年代:1988

数据来源: WILEY

摘要:

AbstractTwenty‐two cases of vascular graft failures (thrombosis, pseudoaneurysm, dilation, infection) were investigated by means of physicochemical, histological, and ultrastructural studies. A general decrease of mechanical resistance to stress of the prostheses was observed. Its magnitude ranged from 2 to 75% of the values of identical virgin prostheses and there was no relation with the duration of implantation. In addition to the breakage of yarn filaments (SEM), migration of fiber debris (histology) was observed in 7 cases. The structure of the polyester molecule had evolved after implantation. A decrease of crystallinity (x‐ray diffraction and differential scanning calorimetry) was noted. These observations raise the question of the established stability of vascular prostheses and emphasize the need for further investigations in human graft retrieval progr

ISSN:0021-9304    

DOI:10.1002/jbm.820220705

出版商:John Wiley&Sons, Inc.    

年代:1988

数据来源: WILEY

摘要:

AbstractThe corrosion resistance of various nickel‐containing alloys was measured in artificial sweat (perspiration) using the Tafel extrapolation method. It was found that Ni, CuNi 25 (coin alloy), NiAl (colored intermetallic compounds), WC + Ni (hard metal), white gold (jewelry alloy), FN42 and Nilo Alby K (controlled expansion alloys), and NiP (electroless nickel coating) are in an active state and dissolve readily in oxygenated artificial sweat. By contrast, austenitic stainless steels, TiC + Mo2C + Ni (hard metal), NiTi (shape‐memory alloy), Hastelloy χ (superalloy), Phydur (precipitation hardening alloy), PdNi and SnNi (nickel‐containing coatings) are in a passive state but may pit under certain conditions. Cobalt, Cr, Ti, and some of their alloys were also investigated for the purpose of comparison. Cobalt and its alloys have poor corrosion resistance except for Stellite 20. Chromium and high‐chromium ferritic stainless steels have a high pitting potential but the latter are susceptible to crevice corrosion. Ti has a pitting potential>3 V. Comparison between thein vitromeasurements of the corrosion rate of nickel‐based alloys and the clincial observation of the occurrence of contact dermatitis is

ISSN:0021-9304    

DOI:10.1002/jbm.820220706

出版商:John Wiley&Sons, Inc.    

年代:1988

数据来源: WILEY

ISSN:0021-9304    

DOI:10.1002/jbm.820220707

出版商:John Wiley&Sons, Inc.    

年代:1988

数据来源: WILEY

ISSN:0021-9304    

DOI:10.1002/jbm.820220701

出版商:John Wiley&Sons, Inc.    

年代:1988

数据来源: WILEY