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in subjects: "Organs"

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Tumor production in Syrian hamsters following inhalation of PuO/sub 2/--ZrO/sub 2/ aerosol

Syrian golden hamsters of both sexes were exposed to aerosols of ZrO/sub 2/ containing PuO/sub 2/. The starting material in the aerosol generator also had a small amount of /sup 57/Co added as a tracer. The mixture of all three constituents was nebulized and the droplets passed through a heating column at 1000/sup 0/C. Aerosol sampling was accomplished with a cascade impactor and electrostatic precipitator. The median aerodynamic diameters in all inhalation runs were approximately 2 ..mu..m wit… more

Date: January 1, 1978

Creator: Thomas, R. G. & Smith, D. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Drug metabolizing enzyme systems and their relationship to toxic mechanisms

The metabolism and toxicity of 3-methylfuran (3-MF) are described. The major product of metabolic activation of 3-MF appears to be disemicarbazones. Cursory description of toxic effects of 3-MF on lung and kidneys are provided. 18 refs.

Date: January 1, 1983

Creator: Boyd, M. R.; Ravindranath, V.; Burka, L. T.; Dutcher, J. S.; Franklin, R. B.; Statham, C. N. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

In-Vitro and in-Vivo Characterization of Ruthenium-Bleomycin Compared to Cobalt- and Copper-Bleomycin

Bleomycin (BLM) has undergone extensive investigation both as a cancer chemotherapeutic agent, and as a carrier for radionuclides for tumor imaging. The available methods or the radionuclides used, however, have had limited effectiveness. Although labeling of BLM with /sup 103/Ru has been reported earlier, we carried out a study to develop a more reproducible method of labeling particularly for use with Brookhaven Linac Isotope Producer produced /sup 97/Ru. Ruthenium-97 has favorable physical p… more

Date: January 1, 1986

Creator: Shao, H. S.; Meinken, G. E.; Srivastava, S. C.; Slosman, D.; Sacker, D. F.; Som, P. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Clonal theory of radiation carcinogenesis

In some cases, usually involving high-LET radiations, the dose response at low doses follows a power function of dose with exponent less than one over a wide dose range. This type of response is of great interest since (a) it implies greater effect per unit dose at progressively smaller doses, and (b) it is not predicted by most models and theories of radiobiology. A theoretical framework is presented for responses having the above characteristics over a dose range extending over a factor of 10… more

Date: January 1, 1982

Creator: Baum, J.W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Radiation induced micrencephaly in guinea pigs

A brain weight deficit of about 70 mg was induced at doses of approximately 75-mGy and a deficit of 60 mg was induced at 100 mGy. This confirms the effects projected and observed by Wanner and Edwards. Although the data do not demonstrate a clear dose-response relationship between the 75-mGy and 100-mGy groups, the data are statistically consistent with a dose-response effect because of the overlapping confidence intervals. The lack of a statistically significant observation is most likely rela… more

Date: January 1, 1991

Creator: Wagner, L.K.; Johnston, D.A. & Felleman, D.J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Stochastic modelling of physiologic processes with radiotracers and positron emission tomography

The compartment model, so often used in nuclear medicine and in pharmacokinetics, is formed by a set of linear differential equations of order one with constant coefficients; its validity depends upon the hypothesis that the system described contains a finite number of components, and that each component is homogeneous. These hypotheses exclude the presence of diffusion and of age-dependent processes, or in general of transport of a non-Markovian nature. The fact that frequently the experimenta… more

Date: January 1, 1982

Creator: Rescigno, A.; Lambrecht, R. M. & Duncan, C. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Research on human genetics in Iceland. Progress report

Records of the Icelandic Population are being used to investigate the possible inheritance of disabilities and diseases as well as other characters and the effect of environment on man. The progress report of research covers the period 1977 to 1980. The investigation was begun in 1965 by the Genetical Committee of the University of Iceland and the materials used are demographic records from the year 1840 to present and various medical information. The records are being computerized and linked t… more

Date: October 31, 1980

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Tumors of the skin and soft tissues

The majority of the body surface is covered by the skin. Many internal disorders are reflected in the condition of the skin. One of the major functions of the skin is protection of the other organ systems from a variety of environmental insults. In this role, the skin itself is exposed to factors that can ultimately cause chronic diseases and cancer. Since it is relatively easy to recognize skin abnormalities, most skin cancers are brought to professional attention sooner than other types of ca… more

Date: October 1, 1991

Creator: Weller, R. E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

FY 1992 task plans for the Hanford Environmental Dose Reconstruction Project

Phase 1 of the HEDR Project was designed to develop and demonstrate a method for estimating radiation doses people may have received from Hanford Site operations since 1944. The method researchers developed relied on a variety of measured and reconstructed data as input to a modular computer model that generates dose estimates and their uncertainties. As part of Phase 1, researchers used the reconstructed data and computer model to calculate preliminary dose estimates for populations from limit… more

Date: October 1, 1991

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Emission computed tomography of /sup 18/F-fluorodeoxyglucose and /sup 13/N-ammonia in stroke and epilepsy

The ECAT Positron Tomograph was used to scan normal control subjects, stroke patients at various times during recovery, and patients with partial epilepsy during EEG monitoring. /sup 18/F-fluorodeoxyglucose (/sup 18/FDG) and /sup 13/N-Ammonia (/sup 13/NH/sub 3/) were used as indicators of abnormalities in local cerebral glucose utilization (LCMR/sub glc/) and relative perfusion, respectively. Hypometabolism, due to deactivation or minimal damage, was demonstrated with the /sup 18/FDG scan in de… more

Date: January 1, 1980

Creator: Kuhl, D. E.; Phelps, M. E. & Engel Jr., J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

PNL In Vivo Phantom Library Calibration Program

No Description Available.

Date: October 1, 1991

Creator: Olsen, P. C.; Nichols, L. L.; Sisk, D. R. (Pacific Northwest Lab., Richland, WA (United States)) & Loesch, R. M. (USDOE, Washington, DC (United States))

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Analytical review of structure and regulation of hemopoiesis

The development of knowledge on the structure of hemopoiesis and its regulation can be divided into four broad areas: descriptive morphology, kinetics of cell proliferation, regulation of rates of cell proliferation through interaction of molecular regulators and their cell surface receptors, and clinical applications. 60 refs., 6 figs.

Date: January 1, 1987

Creator: Cronkite, E.P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Radiation protection: an analysis of thyroid blocking. [Effectiveness of KI in reducing radioactive uptake following potential reactor accident]

An analysis was performed to provide guidance to policymakers concerning the effectiveness of potassium iodide (KI) as a thyroid blocking agent in potential reactor accident situations, the distance to which (or area within which) it should be distributed, and its relative effectiveness compared to other available protective measures. The analysis was performed using the Reactor Safety Study (WASH-1400) consequence model. Four categories of accidents were addressed: gap activity release acciden… more

Date: January 1, 1980

Creator: Aldrich, D.C. & Blond, R.M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Estimated risk from exposure to radon decay products in US homes

Recent analyses now permit direct estimation of the risks of lung cancer from radon decay products in US homes. Analysis of data from indoor monitoring in single-family homes yields a tentative frequency distribution of annual-average /sup 222/Rn concentrations averaging 55 Bq m/sup -3/ and having 2% of homes exceeding 300 Bq m/sup -3/. Application of the results of occupational epidemiological studies, either directly or using recent advances in lung dosimetry, to indoor exposures suggests tha… more

Date: May 1, 1986

Creator: Nero, A.V. Jr.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Purification of phospholamban, a 22,000 dalton protein from cardiac sarcoplasmic reticulum that is specifically phosphorylated by cyclic AMP-dependent protein kinase

Very low concentrations deoxycholate (DOC) were used to isolate two proteins from canine cardiac sarcoplasmic reticulum. These two proteins are phospholamban, a 22,000 dalton protein, and the Ca/sup 2 +/ + Mg/sup 2 +/-ATPase, the major protein of the sarcoplasmic reticulum, responsible for the active transport of calcium. The 22,000 dalton protein is first solubilized in a very low concentration of DOC and then subjected to column chromatography. After molecular weight sieving on a Sephadex G-7… more

Date: January 1, 1979

Creator: Bidlack, J. M. & Shamoo, A. E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Dose-rate conversion factors for external exposure to photons and electrons

Dose-rate conversion factors for external exposure to photons and electrons have been calculated for approximately 500 radionuclides of potential importance in environmental radiological assessments. The dose-rate factors were obtained using the DOSFACTER computer code. The results given in this report incorporate calculation of electron dose-rate factors for radiosensitive tissues of the skin, improved estimates of organ dose-rate factors for photons, based on organ doses for monoenergetic sou… more

Date: August 1, 1981

Creator: Kocher, David C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Accommodation project for physically restricted personnel. Phase II. Low back project

This report presents a course outline and its associated criteria for a Back Pain Prevention Program for Sandia National Laboratories.

Date: August 1, 1982

Creator: Young, L. L. & Mossman, P. B.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

UV action spectra for mammalian systems: their implications for the predicted effects of ozone depletion on skin cancer incidence

The predicted environmental effect of UV-B depend on the action spectrum for the response studied. Since such spectra change rapidly - usually decreasing with increasing wavelength - and since the biological effects depend on the product of the action spectrum and the sun's spectrum at the surface of the earth which decreases with decreasing wavelength, a slight change in action spectrum will markedly influence the predicted effects of ozone depletion on biological systems. Thus, the key, but b… more

Date: January 1, 1982

Creator: Setlow, R.B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Microdistribution of lead in bone: A new approach

A knowledge of the microdistribution of lead in bone is important in order to understand the mechanisms for accumulation and release of lead. The availability of the synchrotron x-ray microscope for sensitive measurements of bone content and distribution of lead provides a valuable tool which, when combined with kinetic, balance, and tissue measurements, can lead to better evaluation of lead toxicity. It may also provide the basis for the development of a suitable model of how lead behaves in t… more

Date: January 1, 1991

Creator: Jones, K.W. (Brookhaven National Lab., Upton, NY (United States)); Bockman, R.S. (Cornell Univ., New York, NY (United States). Medical Coll.) & Bronner, F. (Connecticut Univ. Health Center, Farmington, CT (United States))

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Indoor concentrations of radon 222 and its daughters: sources, range, and environmental influences

The author here reviews what is presently known about factors affecting indoor concentrations of radon 222 and its daughters. In US single-family homes, radon concentrations are found to average about 1.5 pCi/1, but substantially higher concentrations occur frequently: perhaps a million US homes have concentrations exceeding 8 pCi/1 (from which occupants receive radiation doses comparable to those now experienced by uranium miners). The major contributor to indoor radon is ordinary soil underly… more

Date: April 1, 1985

Creator: Nero, A.V. Jr.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Mathematical Model for Predicting the Probability of Acute Mortality in a Human Population Exposed to Accidentally Released Airborne Radionuclides. Final Report for Phase I

A mathematical model was constructed for the purpose of predicting the fraction of human population which would die within 1 year of an accidental exposure to airborne radionuclides. The model is based on data from laboratory experiments with rats, dogs and baboons, and from human epidemiological data. Doses from external, whole-body irradiation and from inhaled, alpha- and beta-emitting radionuclides are calculated for several organs. The probabilities of death from radiation pneumonitis and f… more

Date: May 1, 1980

Creator: Filipy, R. E.; Borst, F. J.; Cross, F. T.; Park, J. F.; Moss, O. R.; Roswell, R. L. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Kinetics of reversible-sequestration of leukocytes by the isolated perfused rat lung

The kinetics and morphology of sequestration and margination of rat leukocytes were studied using an isolated perfused and ventilated rat lung preparation. Whole rat blood, bone marrow suspension, or leukocyte suspensions, were used to perfuse the isolated rat lung. The lung was also perfused with latex particle suspensions and the passage of particles through the lung capillaries was studied. When a leukocyte suspension was perfused through the lung in the single-pass mode, the rate of sequest… more

Date: August 1, 1980

Creator: Goliaei, B.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Effect of physical activity on body composition

It has been noted that the deleterious effects on bone calcium of prolonged periods of inactivity, such as bed rest, are halted following resumption of activity. It would seem possible in light of the observations that have been made, that exercise may stimulate bone formation and perhaps counter, to some extent, bone loss as observed in the osteoporosis of aging. The present study was designed to determine the relation between total body calcium, total body potassium and bone mineral content o… more

Date: January 1, 1980

Creator: Zanzi, I; Ellis, K J; Aloia, J & Cohn, S H

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

MLE (Maximum Likelihood Estimator) reconstruction of a brain phantom using a Monte Carlo transition matrix and a statistical stopping rule

In order to study properties of the Maximum Likelihood Estimator (MLE) algorithm for image reconstruction in Positron Emission Tomographyy (PET), the algorithm is applied to data obtained by the ECAT-III tomograph from a brain phantom. The procedure for subtracting accidental coincidences from the data stream generated by this physical phantom is such that he resultant data are not Poisson distributed. This makes the present investigation different from other investigations based on computer-si… more

Date: October 1, 1987

Creator: Veklerov, E.; Llacer, J. & Hoffman, E.J.

Item Type: Article

Partner: UNT Libraries Government Documents Department