EPR and ENDOR Studies of1H and14N Hyperfine and Quadrupolar Couplings in Crystals ofl-O-Serine Phosphate after X-Irradiation at 295 K

Audun Sanderud; Einar Sagstuen

doi:10.1021/jp960063x

Electron Microscopic Examination of a Transplantable Rat Mammary Carcinoma

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100099842 ◽

1968 ◽

Vol 26 ◽

pp. 20-21

Author(s):

S. Shirahama ◽

G. C. Engle ◽

R. M. Dutcher

Keyword(s):

Electron Microscope ◽

Osmium Tetroxide ◽

Electron Microscopic Examination ◽

Undifferentiated Carcinoma ◽

Uranyl Acetate ◽

Sprague Dawley ◽

Electron Microscopic ◽

North West ◽

X Irradiation ◽

Tissue Specimens

A transplantable carcinoma was established in North West Sprague Dawley (NWSD) rats by use of X-irradiation by Engle and Spencer. The tumor was passaged through 63 generations over a period of 32 months. The original tumor, an adenocarcinoma, changed into an undifferentiated carcinoma following the 19th transplant. The tumor grew well in NWSD rats of either sex at various ages. It was invariably fatal, causing death of the host within 15 to 35 days following transplantation.Tumor, thymus, spleen, and plasma from 7 rats receiving transplants of tumor at 3 to 9 weeks of age were examined with an electron microscope at intervals of 8, 15, 22 and 30 days after transplantation. Four normal control rats of the same age were also examined. The tissues were fixed in glutaraldehyde, postfixed in osmium tetroxide and embedded in Epon. The plasma was separated from heparanized blood and processed as previously described for the tissue specimens. Sections were stained with uranyl acetate followed by lead citrate and examined with an RCA EMU-3G electron microscope.

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The Response of Testis Cells to Low Dose X-Irradiation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100099155 ◽

1981 ◽

Vol 39 ◽

pp. 542-543

Author(s):

D. E. Philpott ◽

W. Sapp ◽

C. Williams ◽

Joann Stevenson ◽

S. Black

Keyword(s):

Electron Microscopy ◽

Stem Cell ◽

Light Microscopy ◽

Dose Level ◽

Cross Sections ◽

Low Dose ◽

Light And Electron Microscopy ◽

Cellular Responses ◽

Post Irradiation ◽

X Irradiation

The response of spermatogonial cells to X-irradiation is well documented. It has been shown that there is a radiation resistent stem cell (As) which, after irradiation, replenishes the seminiferous epithelium. Most investigations in this area have dealt with radiation dosages of 100R or more. This study was undertaken to observe cellular responses at doses less than 100R of X-irradiation utilizing a system in which the tissue can be used for light and electron microscopy.Brown B6D2F1 mice aged 16 weeks were exposed to X-irradiation (225KeV; 15mA; filter 0.35 Cu; 50-60 R/min). Four mice were irradiated at each dose level between 1 and 100 rads. Testes were removed 3 days post-irradiation, fixed, and embedded. Sections were cut at 2 microns for light microscopy. After staining, surviving spermatogonia were identified and counted in tubule cross sections. The surviving fraction of spermatogonia compared to control, S/S0, was plotted against dose to give the curve shown in Fig. 1.

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Eds Of Radioactive Particles By Self-Induced Fluorescence

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010013479x ◽

1990 ◽

Vol 48 (2) ◽

pp. 238-239

Author(s):

Gregory L. Finch ◽

Richard G. Cuddihy

Keyword(s):

Electron Beam Irradiation ◽

Nuclear Reactor ◽

X Rays ◽

Reactor Accident ◽

Internal Radiation ◽

X Ray ◽

External Sources ◽

X Irradiation ◽

Available Information ◽

Individual Particles

The elemental composition of individual particles is commonly measured by using energydispersive spectroscopic microanalysis (EDS) of samples excited with electron beam irradiation. Similarly, several investigators have characterized particles by using external monochromatic X-irradiation rather than electrons. However, there is little available information describing measurements of particulate characteristic X rays produced not from external sources of radiation, but rather from internal radiation contained within the particle itself. Here, we describe the low-energy (< 20 KeV) characteristic X-ray spectra produced by internal radiation self-excitation of two general types of particulate samples; individual radioactive particles produced during the Chernobyl nuclear reactor accident and radioactive fused aluminosilicate particles (FAP). In addition, we compare these spectra with those generated by conventional EDS.Approximately thirty radioactive particle samples from the Chernobyl accident were on a sample of wood that was near the reactor when the accident occurred. Individual particles still on the wood were microdissected from the bulk matrix after bulk autoradiography.

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