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[Fluorescence cytophotometric DNA studies of Ewing and osteosarcomas].

The single-cell fluorescence cytometric data presented in this study basing on measurements on 6 osseous Ewing's-Sarcoma and 17 classical osteosarcoma are showing a mirrorlike behaviour to cytological and histological appearance. The cellular monotony in Ewing's-Sarcoma and the polymorphic appearance of osteosarcoma are represented by typical aneuploid DNA-histograms. Ewing's-Sarcoma histogram's show a large peak between the diploid and tetraploid region and little deviation to the octoploid value. The conventional osteosarcomas are characterised by a very polyploid and changeable DNA-histogram with variable blocks and peaks and deviation up to 34c. Special trends in the subtypes are remarkable, but depend on further investigations. DNA-measurements support objectivization of histological appearance on the one hand and the controlling of therapeutical responses on the other hand.

Adolescent↗

PubMedDate not supplied

Physicochemical surface properties of various intraocular lenses.

PURPOSE: It is of major interest to understand how intraocular lens (IOL) surfaces interact with aqueous humor or tissues after implantation. Important parameters to describe the physicochemical surface properties are the contact angle and critical surface tension. Therefore, we performed measurements of the contact angle and critical surface tension of several commercially available IOLs. SETTING: Department of Ophthalmology, Johannes Gutenberg University, Mainz, University Eye Hospital, Tübingen, and Max Planck Institute for Polymer Research, Mainz, Germany. METHODS: A total of 17 commercially available standard quality IOL types (6 of each) of different materials from several manufacturers were studied. Scanning electron microscopy and contact angle measurements using the sessile drop method were made. RESULTS: The sessile drop method differentiated all materials based on their surface forces. The contact angle (mean +/- SD) ranged from 56.5 +/- 3.8b 3. CONCLUSION: Contact angles differed between the IOLs depending on the IOL material with the lowest contact angle in the heparin-surface-modified IOL. The contact angle measurement method generates useful information about the material surface and its potential biomaterial interactions.

Acrylic Resins↗