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Variants And Polymorphisms Of Three Repetitive Dna Families In The Human Genome, Robert M. Roudabush May 1989

Variants And Polymorphisms Of Three Repetitive Dna Families In The Human Genome, Robert M. Roudabush

Electronic Theses and Dissertations

A novel 0.6 kb LINE family in human DNA, designated L2Hs, has been described (Musich and Dykes 1986). Studies employing clone N6.4, containing three 0.6 kb segments of this family, indicate that these sequences are interspersed and moderately repetitive. Two additional variant sequences of the L2Hs family, N6.1 and N6.3, have been identified. Restriction mapping of each cloned segment indicates similarities among N6.4, N6.3 and N6.1. When the cloned DNAs were cleaved with restriction enzymes and subjected to cross-hybridization, each cloned insert produced a pattern indicating that the sequences contained in N6.1 and N6.3 are represented in at least one …


Purification And Characterization Of An Inhibitor Of Thymidine Uptake From Culture Supernatants Of Human Tonsil Lymphocytes, Abdolreza Zarnegar May 1987

Purification And Characterization Of An Inhibitor Of Thymidine Uptake From Culture Supernatants Of Human Tonsil Lymphocytes, Abdolreza Zarnegar

Electronic Theses and Dissertations

Lymphocytes from human tonsils were cultured in the absence of serum for 3 days. In the presence of the concentrated culture supernatant the proliferative response of PBL, to con A, as measured by the uptake of ('3)H-tdr, was significantly reduced. The suppressor substance was referred to as SMAL (suppressor of mitogen activated lymphocytes). The estimated molecular weight of SMAL under nondenaturing conditions was 100,000-300,000. SMAL also suppressed the incorporation of ('3)H-tdr by a variety of mouse and human tumor cell lines. The activity of SMAL was sensitive to pronase and heating at 100(DEGREES)C for 30 minutes but insensitive to RNase. …


Isolation And Characterization Of Temperature-Sensitive Protein Synthesis Mutants Of Escherichia Coli By Directed Mutagenesis Of The Defective Bacteriophage Lambda Fus2, Kenton L. Lohman Dec 1985

Isolation And Characterization Of Temperature-Sensitive Protein Synthesis Mutants Of Escherichia Coli By Directed Mutagenesis Of The Defective Bacteriophage Lambda Fus2, Kenton L. Lohman

Electronic Theses and Dissertations

Mutagenesis of the defective transducing bacteriophage lambda fus2 was used to isolate a collection of temperature-sensitive mutants of E. coli in the major ribosomal protein gene cluster. Four mutants were examined in detail. Two of the mutants were resistant to the ribosomal antibiotics neamine and spectinomycin. Another mutant was defective in 50S ribosomal subunit assembly at 42(DEGREES)C. The 30S subunit proteins S17 and S19 were changed in two different mutants. Each protein migrated as a more basic species in two-dimensional gels of ribosomal proteins. Ribosomes from each of the four mutants examined showed a temperature-dependent reduction in translational activity in …


Human Lung Tryptase Purification And Characterization, Timothy J. Smith May 1985

Human Lung Tryptase Purification And Characterization, Timothy J. Smith

Electronic Theses and Dissertations

Human lung tryptase (HLT), a mast cell derived trypsin-like enzyme, was isolated from whole human lung tissue obtained at autopsy. Increased yields from this purification process allowed extensive characterization of the enzyme. One of the critical steps in the purification scheme was the use of a linear heparin gradient to elute active material from cellulose phosphate. Gel filtration studies in 1.0 M NaCl yielded an apparent M(,r) of 135,000, and subsequent electrophoresis on sodium dodecyl sulfate-polyacrylamide gels demonstrated the presence of two active species with apparent M(,r) = 30,900 and 31,600. Enzymatic activity was sensitive to NaCl concentrations above 0.05 …


Characterization Of Kpni Interspersed, Repetitive Dna Sequence Families And Their Association With The Nuclear Matrix, Joseph A. Chimera Dec 1984

Characterization Of Kpni Interspersed, Repetitive Dna Sequence Families And Their Association With The Nuclear Matrix, Joseph A. Chimera

Electronic Theses and Dissertations

The KpnI, 1.2 and 1.5 kb families of interspersed repetitive DNAs from the African green monkey genome were isolated and characterized. Each family contains three populations of segments based on their sequence lengths and susceptibility to cleavage by the restriction enzymes KpnI and RsaI. The first population contains the smallest segments which are susceptible to both KpnI and RsaI cleavage and have fragment lengths of 1.2 kb (1.2 kb family) and 1.5 kb (1.5 kb family) respectively. The members in this population are referred to as KpnI-sensitive segments. The second population contains longer segments (> 2 kb) which represent fusions …


Methemoglobin., Herbert Friedman Jan 1948

Methemoglobin., Herbert Friedman

Electronic Theses and Dissertations

No abstract provided.


Studies On Synthesis By Enzymatic Catalysis., Charles Henry Wabnitz 1916-2004 Jan 1947

Studies On Synthesis By Enzymatic Catalysis., Charles Henry Wabnitz 1916-2004

Electronic Theses and Dissertations

No abstract provided.


A Study Of Factors Influencing The Hydrolysis Of Corn Amylopectin By Barley Malt Enzymes., Thelma Munsey Back 1918-2006 Jan 1945

A Study Of Factors Influencing The Hydrolysis Of Corn Amylopectin By Barley Malt Enzymes., Thelma Munsey Back 1918-2006

Electronic Theses and Dissertations

No abstract provided.


Activated Carbon From Grapefruit Waste., Delbert Van Fletcher 1918-2005 Jan 1941

Activated Carbon From Grapefruit Waste., Delbert Van Fletcher 1918-2005

Electronic Theses and Dissertations

No abstract provided.


A Study Of The Kjeldahl Method And A Modification For The Determination Of Nitrogen In Alcoholic Distillates., Margie M. Miller Jan 1940

A Study Of The Kjeldahl Method And A Modification For The Determination Of Nitrogen In Alcoholic Distillates., Margie M. Miller

Electronic Theses and Dissertations

No abstract provided.


A Study Of The Effect Of Rickets Upon The Cholesterol And Fatty Acid Content Of The Brain., Willa Holzheimer 1909-1996 Jan 1938

A Study Of The Effect Of Rickets Upon The Cholesterol And Fatty Acid Content Of The Brain., Willa Holzheimer 1909-1996

Electronic Theses and Dissertations

No abstract provided.


The Role Of Membranes And Phase Boundaries In Generating Electric Currents In Living Tissues., Norman E. Epstein Jan 1934

The Role Of Membranes And Phase Boundaries In Generating Electric Currents In Living Tissues., Norman E. Epstein

Electronic Theses and Dissertations

No abstract provided.


The Organic Acid Content Of Normal And Pathological Blood By The Use Of The Quinhydrone Electrode., Letitia Green Jan 1933

The Organic Acid Content Of Normal And Pathological Blood By The Use Of The Quinhydrone Electrode., Letitia Green

Electronic Theses and Dissertations

No abstract provided.


The Effect Of Sodium Chloride Upon The Fission Rate Within A Single Clone Of Paramecium Caudatum And The Heritability Of That Effect., Mary C. Adolph Jan 1932

The Effect Of Sodium Chloride Upon The Fission Rate Within A Single Clone Of Paramecium Caudatum And The Heritability Of That Effect., Mary C. Adolph

Electronic Theses and Dissertations

No abstract provided.


The Natural Factors In The Selection Of Diet., Lamar William Neblett Jan 1931

The Natural Factors In The Selection Of Diet., Lamar William Neblett

Electronic Theses and Dissertations

No abstract provided.