Scanning and transmission electron microscopy of biodegradable microspheres (DSM) in blood vessels.

A type of biodegradable microsphere (DSM), approximately 45 microns in diameter, made of polymerized potato starch (Pharmacia, Sweden) was intravenously injected into rats to observe the state of DSM in small blood vessels in the kidney and liver at the electron microscopic level. Prior to their digestion with amylase, individual DSM changed their round shape to an irregularly folded one to occupy almost the whole area of the lumen. At the transmission electron microscopic level, DSM were impregnated with colloidal iron and were easily identified.

Intraduodenally administered 14C-urokinase in Macaca Irus revealed by autoradiography.

Intraduodenally administered 14C-urokinase (14C-UK) was located in Macaca Irus by autoradiography. Sagittal sections, approximately 40 micron thick, of a frozen monkey were applied against X-ray films. Autoradiograms thus obtained indicated that a part of intraduodenally administered 14C-UK was incorporated into the systemic blood circulation by transintestinal mucosal membrane.

Calcium Detection in Secretion Granules of Avian Oviduct by Scanning Electron Microscopy (SEM) and Energy-dispersive X-Ray Microanalysis (EDX) .

Secretion granules in the shell gland, isthmus, and albumin-secreting region of the hen oviduct were analyzed with WET-scanning electron microscopy (SEM) and EDX, a combination of wide-angle backscattered electron detector (BED) and energy-dispersive X-ray microanalyzer (EDX). Glutaraldehyde-fixed but unhydrated, unstained, and uncoated samples were analyzed; Ca was localized in all secretion granules in all three sections of the hen oviduct studied.