89 Matching Results

Search Results

Advanced search parameters have been applied.
in subjects: "Cell Cultures"  
Results: 1 - 24 next
open access

Growth regulation by macrophages

Description: The evidence reviewed here indicates that macrophages, either acting alone or in concert with other cells, influence the proliferation of multiple types of cells. Most of the data indicate that these effects are mediated by soluble macrophage-elaborated products (probably proteins) although the role of direct cell-to-cell contacts cannot be ruled out in all cases. A degree of success has been achieved on the biochemical characterization of these factors, due mainly to their low specific activit… more
Date: January 1, 1982
Creator: Wharton, W.; Walker, E. & Stewart, C.C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Excision repair of bulky lesions in the DNA of mammalian cells

Description: The report examines the process of excision repair of pyrimidine dimers from uv-irradiated and chemically challenged human cells. It is shown by means of a sensitive endonuclease assay that the amount of excision observed depends upon the isotope used to label cells, and that XP heterozygotes are between normals and XPs. (ACR)
Date: January 1, 1980
Creator: Setlow, R B & Grist, E
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Biomedical applications of digital autoradiography with a MWPC

Description: A Multiwire Proportional Chamber (MWPC) was used as a ..beta../sup -/ radioactivity detector in biological and medical applications. Two different kinds of experiments were performed: the study of variations in the ability of cell clones to incorporate a radioactive precursor of DNA biosynthesis (/sup 3/H-thymidine) and the regional carbohydrate consumption in myocardial tissue by means of a deposit tracer of glucose metabolism (/sup 3/H-deoxyglucose).
Date: May 1, 1982
Creator: Bellazzini, R.; Betti, G.; Del Guerra, A.; Massai, M. M.; Ragadini, M.; Spandre, G. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

DNA repair in human cells exposed to combinations of carcinogenic agents

Description: Normal human and XP/sup 2/ fibroblasts were treated with uv plus uv-mimetic chemicals. The uv dose used was sufficient to saturate the uv excision repair system. Excision repair after combined treatments was estimated by unscheduled DNA synthesis, BrdUrd photolysis, and the loss of sites sensitive to a uv specific endonuclease. Since the repair of damage from uv and its mimetics is coordinately controlled we expected that there would be similar rate-limiting steps in the repair of uv and chemic… more
Date: January 1, 1980
Creator: Setlow, R.B. & Ahmed, F.E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Regulation of hemopoiesis: inhibitors and stimulators produced by a murine bone marrow stromal cell line (H-1)

Description: A murine cell line (H-1) probably derived from the adventitial reticular cell has been isolated and preserved. This line produces: (1) CSF; (2) a labile inhibitor of CFU-c proliferation with preferential action on granulopoiesis; (3) PGE; (4) proliferation inhibitors of BFU-E and GEMM; and (5) suppression of entry of CFU-S into DNA synthesis in vitro. It is postulated that the adventitial reticular cell (ARC) may play a major regulatory role in hemopoiesis through intramedullary production of t… more
Date: January 1, 1982
Creator: Cronkite, E. P.; Miller, M. E.; Garnett, H. & Harigaya, K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Toxicologic studies of SRC materials

Description: Investigations on the toxicity of SRC materials are reported. Toxicological studies include: microbial mutageneis (Ames test); in vitro mammalian cell toxicity and transformation assays; epidermal carcinogenesis (skin painting); acute and subchronic oral toxicity; developmental toxicity; dominant lethal assays; inhalation toxicity; and dosimetry and metabolism. The materials tested include: SRC-I process solvent, wash solvent, and light oil; SRC-II heavy distillate, middle distillate, and light… more
Date: February 1, 1980
Creator: Mahlum, D. D.; Pelroy, R. A.; Drucker, H.; Wilson, B. W.; Massey, M. J. & Schmalzer, D. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Health effects of combustion-generated soot and polycyclic aromatic hydrocarbons. Progress report, May 1, 1979-April 30, 1980. [Lead abstract]

Description: Mutagen studies on soot and soot components are reported in aspects dealing from quantitative chemical analyses of samples and mutagenesis of cells and microorganisms exposed to mutagens, to bioassay developments and techniques. Several polycyclic aromatic hydrocarbons are characterized and discussed.
Date: May 1, 1980
Creator: Thilly, W. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Radiobiology of pions at LAMPF

Description: Recent radiobiology data for pion beams used in therapy are presented. The biological systems used were cultured cells suspended in gelatin and intestinal crypt assay. The importance of fast neutrons from pion stars in large treatment volumes is discussed. The data for compensating the depth dose distribution to produce uniform cell killing across the peak region are presented. The changes in biological effectiveness with peak width for pion beams (unlike heavy ions) are small because of fast n… more
Date: January 1, 1982
Creator: Raju, M.R. & Tokita, N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

DNA replication and the repair of DNA strand breaks in nuclei of Physarum polycephalum. Terminal report, August 1, 1978-March 31, 1980

Description: Nuclei isolated from Physarum are able to replicate approximately 15% of the total genome in a manner which is qualitatively similar to the DNA replication process occurring in the intact organism. Such nuclei, however, are defective in the joining of Okazaki intermediates in vitro. Two DNA polymerase species, isolated from nuclei or intact plasmodia of this organism, can be separated by sucrose density gradient centrifugation. Total DNA polymerase activity is low in nuclei isolated during mito… more
Date: January 1, 1980
Creator: Brewer, E. N. & Evans, T. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Quantitative and molecular analyses of mutation in a pSV2gpt transformed CHO cell line

Description: Following NDA-mediated gene transfer we have isolated a cell line useful for studying gene mutation at the molecular level. This line, AS52, derived from a hypoxanthine-guanine phosphoribosyl transferase (HGPRT) deficient Chinese hamster ovary (CHO) cell line, carries a single copy of the E. coli xanthine-guanine phosphoribosyl transferase (XGPRT) gene (gpt) and exhibits a spontaneous mutant frequency of 20 TG/sup r/ mutants/10/sup 6/ clonable cells. As with HGPRT/sup -/ mutants, XGPRT/sup -/ m… more
Date: January 1, 1983
Creator: Stankowski, L.F. Jr.; Tindall, K.R. & Hsie, A.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Annual progress report, July 1, 1979-June 30, 1980

Description: Research progress is reported for the year 1979-1980. The report is divided into sections dealing individually with the divisions of Biomolecular and Cellular Science, Environmental Biology, and Nuclear Medicine. The sections have been individually entered into EDB. (ACR)
Date: January 1, 1980
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Specificity of interaction between carcinogenic polynuclear aromatic hydrocarbons and nuclear proteins: widespread occurrence of a restricted pattern of histone-binding in intact cells

Description: Metabolic activation of benzo(a)pyrene (B(a)P) produces a number of potentially reactive metabolites. The endproducts of one metabolic pathway, 7,8-dihydroxy-9,10-oxy-7,8,9,10-tetrahydro-B(a)P (BPDE) are responsible for essentially all DNA adduct formation in animal cells treated with B(a)P, and a particular stereoisomer, designated (+)-anti-BPDE is thought to be the ultimate carcinogenic derivative of B(a)P. In hamster embryo cell nuclei treated with (+)-anti-BPDE, two of the histones of the n… more
Date: January 1, 1982
Creator: MacLeod, M. C.; Pelling, J. C.; Slaga, T. J.; Nikbakht-Noghrei, P. A.; Mansfield, B. K. & Selkirk, J. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Characterization of Metal Binding Peptides From Cadmium Resistant Plant Cells

Description: The majority of the cellular cadmium (<80%) in cadmium resistant Datura innoxia cells is bound to a small, metal induced peptide which is not metallothionein. This peptide consists of glutamate, cysteine and glycine in a ratio between 2:2:1 and 3:3:1 and has an apparent molecular weight of 776, under denaturing conditions. It is heat stable and complexes with cadmium to produce multimeric forms which are separable by gel filtration. Chemical analyses suggest that some amino acids are not joined… more
Date: January 1, 1985
Creator: Robinson, N. J.; Barton, K.; Naranjo, C. M.; Sillerud, L. O.; Trewhella, J.; Watt, K. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Criteria for the selection of nuclides for radioimmunotherapy

Description: This report describes many factors that need to be considered if radioimmunotherapy is to become a commonplace reality. For beta-emitting radionuclides, two physical features of importance are half-life and energy, with the latter determining the range. These features must be matched to the pharmacokinetics of the carrier and the distribution of the radionuclide, both macroscopically and microscopically. Alpha-particle emitters could be considered for cells that are readily accessible to the la… more
Date: January 1, 1986
Creator: Adelstein, S. J. & Kassis, A. I.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Phytochrome from green plants: assay, purification, and characterization

Description: Phytochrome from the chlorophyllous cells of light-grown higher plants and green algae has been isolated and characterized. We have developed a simple procedure that separates chlorophyll from phytochrome in crude extracts from green tissue thus permitting spectral measurement of the phytochrome in such extracts for the first time. Spectral and immunochemical analysis of phytochrome from green oat tissue indicates the presence of two distinct species of the molecule: a minority species (approx.… more
Date: January 1, 1983
Creator: Quail, P.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Sunlight activation of shale-oil byproducts as measured by genotoxic effects in cultured Chinese hamster cells

Description: Activation of certain classes of promutagens/procarcinogens can be accomplished by exposure to various radiation sources. Retort processes currently in use in the production of shale oil generate significant quantities of process waters which contain a wide spectrum of uv-absorbing, organic material. Photoactivation of these waters with an artificial source of NUV results in genotoxic events in cultured mammalian cells. Since significant amounts (2 to 4%) of solar radiation reaching the earth's… more
Date: January 1, 1981
Creator: Strniste, G.F.; Chen, D.J. & Okinaka, R.T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Environmental research program for slagging fixed-bed coal gasification. Status report, November 1981

Description: A collaborative environmental research program to provide information needed to assess the health and environmental effects associated with large-scale coal gasification technology is being conducted by Argonne National Laboratory (ANL) and the Grand Forks Energy Technology Center (GFETC). The objectives are to: investigate the toxicology and chemical composition of coal gasification by-products as a function of process variables and coal feed; compare the characteristics of isokinetic side-str… more
Date: February 1, 1982
Creator: Wilzbach, K. E.; Stetter, J. R.; Reilly, Jr., C. A. & Willson, W. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Differential gene expression in neurospora crassa cell types: amplification of rRNA genes. Progress report, July 1979-30 June 1980

Description: The significant results obtained during 1979 to 1980 of the current research program are as follows: (1) the differential rRNA gene amplification in germinated conidia of N.crassa was confirmed. N.crassa rDNAs showed differences in degrees of homology with isolated DNAs from other Neurospora species which could be due to heterogeneity in internal spacers. Studies with N.crassa rDNA clones were initiated to study their heterogeneities. The organization of the Institutional Biohazard Committee (I… more
Date: January 1, 1980
Creator: Dutta, S.K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Characterization of cell suspensions from solid tumors

Description: The desirable features of cells in suspension will necessarily be dependent upon the use for which the cells were prepared. Adequate cell yield or recovery is defined by the measurement to be performed. Retention of cellular morphology is important for microscopic identification of cell types in a heterogenous cell suspension, and may be used to determine whether the cells in suspension are representative of those in the tumor in situ. Different dispersal protocols may yield cells with differen… more
Date: July 10, 1985
Creator: Pallavicini, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Radiation effects in space

Description: The paper discusses the radiation environment in space that astronauts are likely to be exposed to. Emphasis is on proton and HZE particle effects. Recommendations for radiation protection guidelines are presented. (ACR)
Date: January 1, 1986
Creator: Fry, R.J.M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

The glycophorin A assay for somatic cell mutations in humans

Description: In this report we briefly review our past experience and some new developments with the GPA assay. Particular emphasis will be placed on two areas that affect the utility of the GPA assay for human population monitoring. The first is our efforts to simplify the GPA assay to make it more generally available for large population studies. The second is to begin to understand some of the characteristics of human hemopoiesis which affect the accumulation and expression of mutant phenotype cells. 11 … more
Date: August 18, 1989
Creator: Langlois, R.G.; Bigbee, W.L. & Jensen, R.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Legionnaires' disease bacteria in power plant cooling systems: Phase 2

Description: Legionnaires' Disease Bacteria (Legionella) are a normal component of the aquatic community. The study investigated various environmental factors that affect Legionella profiles in power plant cooling waters. The results indicate that each of the four factors investigated (incubation temperature, water quality, the presence and type of associated biota, and the nature of the indigenous Legionella population) is important in determining the Legionella profile of these waters. Simple predictive r… more
Date: April 1, 1985
Creator: Tyndall, R.L.; Christensen, S.W. & Solomon, J.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Repair of neoplastic transformation damage following protracted exposures to /sup 60/Co. gamma. -rays

Description: The incidences of neoplastic transformation induced by /sup 60/Co ..gamma..-rays in exponentially growing mouse embryo 10T1/2 cells were measured following acute and protracted exposures. Delivery of /sup 60/Co ..gamma..-rays at a low dose rate (0.1, 0.5, 2.5 rad/min) compared with a high dose rate (100 rad/min) results in appreciable, dose rate dependent reductions in cell killing and, independent of the effect on cell survival, reduces significantly the incidence of neoplastic transformation.… more
Date: January 1, 1983
Creator: Han, A.; Hill, C. K. & Elkind, M. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
Back to Top of Screen