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Articles 13621 - 13650 of 13689

Full-Text Articles in Biochemistry, Biophysics, and Structural Biology

Leaf Ribonuclease Activity As Related To Virus Infection, And Ribonucleic Acid Concentration, Andrew Chien-Yau Hsu May 1963

Leaf Ribonuclease Activity As Related To Virus Infection, And Ribonucleic Acid Concentration, Andrew Chien-Yau Hsu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ribonucleic acid (RNA) appears to be the entity responsible for infectivity and genetic continuity in certain plant, animal and bacterial viruses. RNA also plays an important role in protein synthesis. The enzymes which are involved in RNA synthesis and degradation have received much attention. Among these enzymes ribonuclease (RNase) has been most thoroughly studied Rnase is widely distributed and has been isolated from many sources such as snake venom, bacteria, the pancreas, and many plant and animal tissues. Most studies with RNase have been concerned with its role in the hydrolysis of RNA in vitro. Therefore, it has generally been …


The Biochemical Differences Associated With Iron Chlorosis In Higher Plants, Daniel Ming-Yi Teng May 1963

The Biochemical Differences Associated With Iron Chlorosis In Higher Plants, Daniel Ming-Yi Teng

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Chlorosis, which is associated with a reduction in the chlorophyll content of leaves, is a major problem in the growing of deciduous fruit trees and some field crops on calcareous soil. Under various soil conditions more than one factor may be involved in the development of chlorosis in plants. A deficiency of magnesium, manganese, zinc or iron, and virus infections can induce chlorosis. It is also induced by the presence of high concentrations of phosphate, bicarbonate, manganese, copper, zinc, or numerous other factors.


Radicinin: Revision Of Its Structure Obtained From Nmr Measurements / D. D. Clarke F. F. Nord N. S. Bhacca Laboratory Of Organic Chemistry And Enzymology Fordham University Bronx 58, New York Spectroscopy Applications Laboratory Varian Associates Palo Alto, California, Donald Dudley Clarke Phd, Friedrich F. Nord, N. S. Bhacca Jan 1963

Radicinin: Revision Of Its Structure Obtained From Nmr Measurements / D. D. Clarke F. F. Nord N. S. Bhacca Laboratory Of Organic Chemistry And Enzymology Fordham University Bronx 58, New York Spectroscopy Applications Laboratory Varian Associates Palo Alto, California, Donald Dudley Clarke Phd, Friedrich F. Nord, N. S. Bhacca

Chemistry Faculty Publications

Radicinin, a metabolite of the formula C12H1205 was isolated from the carrot plant pathogen Stemphylium Tadicinum and described in earlier communications. Hansen isolated a metabolite from S. radicinum that inhibited the growth of Lepidium sativum and named it stemphylone. From the physical and chemical properties described for stemphylone it would appear to be identical with radicinin


Carbon Dioxide Fixation In The Brain / Soll Berl, Genkichiro Takagaki, Donald D Clarke, And Heinrich Waelsch From The New York Psychiatric Institute And The Colleg Eof Physicians And Surgeons, Columbia University, New York, New York, Soll Berl, Genkichiro Takagaki, Donald Dudley Clarke Phd, Heinrich Waelsch Jan 1963

Carbon Dioxide Fixation In The Brain / Soll Berl, Genkichiro Takagaki, Donald D Clarke, And Heinrich Waelsch From The New York Psychiatric Institute And The Colleg Eof Physicians And Surgeons, Columbia University, New York, New York, Soll Berl, Genkichiro Takagaki, Donald Dudley Clarke Phd, Heinrich Waelsch

Chemistry Faculty Publications

Carbon dioxide fixation in brain was studied in cats to which NaHC14O3, with and without ammonia, was administered by intracarotid infusion. Glutamic and aspartic acids, glutamine, glutathione, and γ-aminobutyric acid were isolated from blood, brain, and liver, and their specific activities were determined. The data indicate a significant incorporation of CO2 into the amino acids of the cerebral cortex, presumably by way of the citric acid cycle. Without simultaneous ammonia infusion, the specific activity of aspartic acid is 3 times that of glutamine, whereas in the presence of ammonia the ratios of specific activity of both compounds are closer to …


Worm Eggs: Cost You Money, E.F. Frolik, E.W. Janike Jun 1962

Worm Eggs: Cost You Money, E.F. Frolik, E.W. Janike

School of Veterinary and Biomedical Sciences: Faculty Publications

Contents

One Million Eggs Daily.......... 3

Damaging Trip......... 4

Worm Remedies......... 5

Modern Worm Remedies......... 6

A Control Program.......... 8


Biochemical Studies On The Effect Of Fluoride On Higher Plants, Shang-Fa Yang May 1962

Biochemical Studies On The Effect Of Fluoride On Higher Plants, Shang-Fa Yang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Fluoride occurs naturally in plants, but its presence has attracted attention primarily in certain industrial areas where concentrations are elevated above normal by accumulation from the atmosphere. Certain plant species have been observed to be injured as a result of accumulation of excessive fluoride from the atmosphere. The general symptoms of fluoride injury are necrotic lesions and burning which appear first in the leaf tips and margins.


A Comparative Study Of The Growth Of Polyoma Virus In Two Secondary Cell Lines: Mouse Lymphoma And Normal Mouse Fibroblasts, Rheeta M. Stecker Jun 1961

A Comparative Study Of The Growth Of Polyoma Virus In Two Secondary Cell Lines: Mouse Lymphoma And Normal Mouse Fibroblasts, Rheeta M. Stecker

Loma Linda University Electronic Theses, Dissertations & Projects

In comparing the growth of polyoma virus in secondary cell cultures of a mouse lymphoma (P388D1, a known polyoma-supporting strain) and normal mouse fibroblasts (Earle’s L cells), the following observations have been made.

The L cell is capable of supporting the growth of the polyoma virus with reproduction and release of infectious particles. Viruses appear in the fluid from time to time over a period of several weeks. This probably represents a carrier state of the virus in L cells. Many of the L cells in infected cultures are not killed by the virus infection.

Virus particles released …


The Vitamin B1-Sparing Action Of Sorbitol, Gisela Eleanor Bethsold Jun 1960

The Vitamin B1-Sparing Action Of Sorbitol, Gisela Eleanor Bethsold

Theses and Dissertations

The present study was initiated to determine the effect sorbitol has upon the enzymatic functions of thiamin; specifically, what effect sorbitol bas upon the alpha-ketoglutarate and pyruvate dehydrogenases activities of rat liver mitochondria. In addition, the effect of varying the dietary sorbitol concentration on the development of an athiaminosis was studied, particularly the effect on growth rate.


Preliminary Report: Monolayer Behavior Studies, 1959, Bureau Of Reclamation Jan 1960

Preliminary Report: Monolayer Behavior Studies, 1959, Bureau Of Reclamation

Publications (WR)

During the fall of 1959, monolayer behavior studies were made on two lakes in the southwest; Boulder Basin of Lake Mead, Nevada, and Lake Sahuaro near Phoenix, Arizona. These studies were made to evaluate the effect of geographical and climatological conditions on movement and behavior of monolayers. The Lake Sahuaro tests also were used to provide data for design and development of improved methods of application and maintenance of a film on this lake in anticipation of full scale, evaporation-reduction tests to be performed there during the summer of I960. The Lake Mead studies produced the following general points of …


Comprehensive Survey Of Sedimentation In Lake Mead, 1948-49, W. O. Smith, C. P. Vetter, G. B. Cummings, U.S. Bureau Of Reclamation Jan 1960

Comprehensive Survey Of Sedimentation In Lake Mead, 1948-49, W. O. Smith, C. P. Vetter, G. B. Cummings, U.S. Bureau Of Reclamation

Publications (WR)

Reservoirs are becoming an increasingly prominent feature of the American landscape. Built for flood mitigation and to change a fluctuating river into a dependable source of water for irrigation, power, and other purposes, they are predestined, like natural lakes, to be destroyed sometime following their creation. Sedimentation sooner or later robs most lakes and reservoirs of their capacity to store water. The significance of sedimentation in the life of Lake Mead, the largest artificial reservoir in the world, was realized when the plan for the reservoir was conceived, and an aerial survey of the floor was made in 1935 before …


Studies On The Biological Oxidation Of Ferrous Iron And Chalcopyrite, Loral Alvin Decker Aug 1959

Studies On The Biological Oxidation Of Ferrous Iron And Chalcopyrite, Loral Alvin Decker

Theses and Dissertations

The purpose of this investigation was to determine the effectiveness of the leaching streams from waste copper ore dumps as a nutrient solution for subsequent biological oxidation and solubilization of sulfide minerals. The copper in the leaching streams is precipitated by displacement with iron. As a result of this procedure the solution is high in ferrous iron concentration and has a pH of near 3.7. The bacteria in the leaching streams are capable of oxidizing ferrous iron to the ferric state and sulfide minerals to sulfates. The effects of temperatures, pH, urea, and aeration rate on the oxidation of the …


Biochemical Changes In The Devascularized Femoral Head, Jeanne Wiesseman May 1959

Biochemical Changes In The Devascularized Femoral Head, Jeanne Wiesseman

Loma Linda University Electronic Theses, Dissertations & Projects

A review of the literature indicates that there have been many attempts to determine the viability of the femoral head after trans cervical fracture of the neck of the femur. These methods have included the use of radioactive isotopes, venography, arteriography and intramedullary pressure determinations. None of these methods have proved entirely satisfactory.

The purpose of this investigation was to determine some of the biochemical changes taking place in the devascularized femoral head. Nineteen dogs were used for the experiments. The femoral neck was fractured transcervically and devascularized. Total devascularinations were performed in the majority of the animals. The animals …


Amine Incorporation Into Insulin As Catalyzed By Transglutaminase / M. J. Mycek, D. D. Clarke, A. Neidle And H. Waelsch From The Department Of Biochemistry, College Of Physicians And Surgeons, Columbia University, New York, And The New York State Psychiatric Institute, New York, New York, M. J. Mycek, Donald Dudley Clarke Phd, A. Neidle, Heinrich Waelsch Jan 1959

Amine Incorporation Into Insulin As Catalyzed By Transglutaminase / M. J. Mycek, D. D. Clarke, A. Neidle And H. Waelsch From The Department Of Biochemistry, College Of Physicians And Surgeons, Columbia University, New York, And The New York State Psychiatric Institute, New York, New York, M. J. Mycek, Donald Dudley Clarke Phd, A. Neidle, Heinrich Waelsch

Chemistry Faculty Publications

No abstract provided.


The Relationship Between The Systemic Action Of Various Carbohydrates And The Development Of Subsequent Dental Caries, Pat O. O'Day May 1958

The Relationship Between The Systemic Action Of Various Carbohydrates And The Development Of Subsequent Dental Caries, Pat O. O'Day

Loma Linda University Electronic Theses, Dissertations & Projects

Previous work with rats, hamsters and monkeys has shown a direct relationship between refined diets high in carbohydrates and caries susceptibility. Adequate amounts of vitamins and minerals have been shown to be necessary for proper tooth development and resistance to decay. The glycoprotein content of hamster teeth raised on a non-cariogenic Purina ration was reported to be lower than the amount found in the teeth of animals raised on a high sugar cariogenic diet.

In order to determine the caries susceptibility produced in Albino rats by different common carbohydrates, an artificial feeding technique was utilized in which the amount and …


A Study Of Three Photochemical Activities Of Chloroplasts, Jimmy W. Hinkson Apr 1958

A Study Of Three Photochemical Activities Of Chloroplasts, Jimmy W. Hinkson

Theses and Dissertations

Chloroplasts of sugar beet leaves were subjected to treatment by heating, by incubation at pH 8.5 and pH 5.5, by incubation in ion low water, by sonic oscillation, by digestion with enzymes (lysozyme, pancreatin, and lipase), by extraction with digitonin, and by chemical compounds including 8-hydroxy-quinoline, sodium azide, zinc sulfate, phenyl mercuric acetate, potassium cyanide, 1-allylthiourea, 2,4-dinitrophenol, thymol, and p-chloromercuribenzoate. A comparative study was made of the effects of these treatments upon three photochemical reactions (the photoreduction of 2,6- dichlorophenol indophenol, the photoreduction of indigo carmine in the presence of a couple composed of 2,6-dichlorophenol indophenol and ascorbic acid, and …


Chemosynthetic Microorganisms In Leaching Sulfide Minerals, A. Keith Jameson Jul 1957

Chemosynthetic Microorganisms In Leaching Sulfide Minerals, A. Keith Jameson

Theses and Dissertations

This investigation showed that a single bacterium was capable of sulfide oxidation in exposed ore bodies. This single bacterium was isolated and characterized. It exhibited different characteristics than any previously known organism. It was found to be a chemosynthetic autotroph. An optimum nutrient concentration was determined for pyrite oxidation. The nutrient concentration was determined for pyrite oxidation. The nutrient contains only a source of phosphate and nitrogen. Urea was found to be a better source of nitrogen than ammonium sulfate which had previously been used. The effect of various organic compounds on the oxidation of pyrite was observed. Glucose and …


Some Supplementary Studies With Wheat Proteins, Gerald G. Porter May 1957

Some Supplementary Studies With Wheat Proteins, Gerald G. Porter

Loma Linda University Electronic Theses, Dissertations & Projects

[Abstract Not Included]

Introduction The importance of selecting only foods containing proteins of high nutritive value has been somewhat over-emphasized in the past because of the failure to recognize the possibility of supplementary relationships among proteins that are not of high quality. Hart (11) has wisely suggested that a food should not be relegated to an inferior class because its proteins, when fed alone, are not of high biological value. Sherman (31) has reminded us that with a knowledge of the nutritional chemistry of the proteins of various foods, it becomes relatively easy to utilize their supplementary relationships so that …


Thermodynamics Of Phosphate Absorption On Several Charcoals, James Duncan Beaton May 1957

Thermodynamics Of Phosphate Absorption On Several Charcoals, James Duncan Beaton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Phosphorus has long been recognized by agriculturists as being one of the elements essential for plant growth. Although the total phosphorus content of a soil may be high, the amount of phosphate actually available for plant growth is often low. Many agencies such as inherent low solubilities of phosphate compounds, adsorption on Ca C03, adsorption in the diffuse double layer of clay micelles, and chemical precipitation of phosphate which refers to the removal of phosphate ions from solution and their chemical bonding to the solid phase have been studied to explain the lack of phosphate availability.


An Enzymically Catalyzed Incorporation Of Amines Into Proteins / Nirmal K. Sarkar Donald D. Clarke Heinrich Waelsch Department Of Biochemistry, College Of Physicians And Surgeons, Columbia University, New York, And The New York Psychiatric Institute, New York, N.Y. (U.S.A.), Nirmal K. Sarkar, Donald Dudley Clarke Phd, Heinrich Waelsch Jan 1957

An Enzymically Catalyzed Incorporation Of Amines Into Proteins / Nirmal K. Sarkar Donald D. Clarke Heinrich Waelsch Department Of Biochemistry, College Of Physicians And Surgeons, Columbia University, New York, And The New York Psychiatric Institute, New York, N.Y. (U.S.A.), Nirmal K. Sarkar, Donald Dudley Clarke Phd, Heinrich Waelsch

Chemistry Faculty Publications

In experiments reported some years ago the enzyme-catalyzed exchange of the amide group of glutamine and asparagine with 15N ammonia was demonstrated but an exchange of the amide groups of protein bound dicarboxylic amino acids could not be explored owing to the unfavorable experimental conditions1 . Recently the problem of the metabolism of protein-amide groups was approached again with the aid of 14C-labeled amines, such as ethanolamine or cadaverine. Soluble protein fractions obtained from sucrose homogenates (o.2sM) of the livers of guinea pigs, rats, mice, and rabbits by centrifugation at roo,ooo X g were incubated in the presence of Ca++ …


Synthesis Of Phosphatidyl Peptides I. O-(Distearoyl-L-A-Glycerylphosphoryl)-L-Serylglycylglycine / By Erich Baer, Jonas Maurukas, And Donald D. Clarke (From The Banting And Best Department Of Medical Research, University Of Toronto, Toronto, Canada), Erich Baer, Jonas Maurukas, Donald Dudley Clarke Phd Jan 1957

Synthesis Of Phosphatidyl Peptides I. O-(Distearoyl-L-A-Glycerylphosphoryl)-L-Serylglycylglycine / By Erich Baer, Jonas Maurukas, And Donald D. Clarke (From The Banting And Best Department Of Medical Research, University Of Toronto, Toronto, Canada), Erich Baer, Jonas Maurukas, Donald Dudley Clarke Phd

Chemistry Faculty Publications

The synthesis of a phosphatidyl tripeptide has been accomplished. It was prepared by (a) phosphorylation of D-α,β-distearin with phenylphosphoryl dichloride and pyridine, (b) esterification of the resulting distearoylL- α-glycerylphenylphosphoryl chloride with N-carbobenzoxy-L-serylglycylglycine benzyl ester in the presence of lutidine, and (c) removal of the protective groups by catalytic hydrogenolysis. The O-( distearoyl-L-α-glycerylphosphoryl)- L-serylglycylglycine was obtained in an over-all yield of 12 per cent. The synthesis of N-carbobenzoxy-L-serylglycylglycine benzyl ester, for which two procedures have been reported, has been simplified considerably by condensing N -carbobenzoxy-L-serine with glycylglycine benzyl ester by means of N ,N' -dicyclohexylcarbodiimide. The phosphatidyl tripeptide is cleaved by …


Metabolic Activity Of Protein Amide Groups, Donald Dudley Clarke Phd, Amos Neidle, Nirmal K. Sarkar, Heinrich Waelsch Jan 1957

Metabolic Activity Of Protein Amide Groups, Donald Dudley Clarke Phd, Amos Neidle, Nirmal K. Sarkar, Heinrich Waelsch

Chemistry Faculty Publications

No abstract provided.


Oxidation Of Molybdenite With The Aid Of Microorganisms, Ralph Anderson Aug 1956

Oxidation Of Molybdenite With The Aid Of Microorganisms, Ralph Anderson

Theses and Dissertations

This work represents a study on the biological oxidation of molybdenite, MoS2. The principal objective of this study was to investigate the possibility of the biological oxidation of molybdenite, to determine the physical and chemical conditions under which the oxidative process occurs, and to develop a strain of bacteria or alter the activity of the microorganisms by acclimatization to increase their activity on sulfide minerals, in particular molybdenite. Minerals used in this study were pyrite (FeS2), chalcopyrite (CuFeS2), molybdenite concentrate, and molybdenite ore. The microorganisms used in this investigation were autotrophic bacteria obtained from the leaching streams of Bingham Canyon, …


Photo-Oxidations Sensitized By Physiologically Important Substances, Ernel D. Ihnen Jun 1956

Photo-Oxidations Sensitized By Physiologically Important Substances, Ernel D. Ihnen

Theses and Dissertations

A study of the photo-oxidation of the 2,6-dichlorophenol indophenol-ascorbic couple was undertaken with a view to investigating the postulated mechanism of oxidation by a component of the oxygen evolving sequence operative in photosynthesis. A spectrophotometric method for the measurement of the progress of photo-oxidation was developed. Temperature and pH dependence were determined and the effect of various common inhibitors and physiological substances tested. None of the common Hill reaction inhibitors were effective in the ascorbic acid photo-oxidation in the system used. KCN and catalase as well as a few other high molecular weight proteins were able to inhibit dark auto-oxidation …


L-Serylglycylglycine / By Erich Baer, Jonas Maurukas, And Donald D. Clarke, Erich Baer, Jonas Maurukas, Donald Dudley Clarke Phd Jan 1956

L-Serylglycylglycine / By Erich Baer, Jonas Maurukas, And Donald D. Clarke, Erich Baer, Jonas Maurukas, Donald Dudley Clarke Phd

Chemistry Faculty Publications

A synthesis of the hitherto unreported L-serylglycylglycine by two different methods is described. N-carbobenzoxy L-serylglycylglycine benzyl ester, an intermediate in the preparation of the tripeptide, was found to be a suitable derivative in the synthesis of L-α-phosphatidyl L-serylglycylglycine


Radicinin: A Metabolite From Stemphylium Radicinum. I. Chemistry And Action / D. D. Clarke And F. F. Nord From The Department Of Organic Chemistry And Enzymology, Fordham University, New York, New York, Donald Dudley Clarke Phd, Friedrich F. Nord Jan 1955

Radicinin: A Metabolite From Stemphylium Radicinum. I. Chemistry And Action / D. D. Clarke And F. F. Nord From The Department Of Organic Chemistry And Enzymology, Fordham University, New York, New York, Donald Dudley Clarke Phd, Friedrich F. Nord

Chemistry Faculty Publications

The conditions for the growth of Sterad and isolation of radicinin are described. The formula C12H1205 wasas established for this compound by preparation and analyses of several derivatives. Degradation and spectrophotometric studies were employed to establish the molecular formula. Studies on the mode of action of radicinin revealed that it caused an increase in the rate of dehydrogenation of isopropyl alcohol by FIB, but that it had no effect on the quantity or degree of desaturation of the fat synthesized by FIB


Radicinin: A Metabolite From Stemphylium Radicinum. Ii. On The Mechanism Of Its Biosynthesis / D. D. Clarke And F. F. Nord From The Department Of Organic Chemistry And Enzymology, Fordham University, New York, New York, Donald Dudley Clarke Phd, Friedrich F. Nord Jan 1955

Radicinin: A Metabolite From Stemphylium Radicinum. Ii. On The Mechanism Of Its Biosynthesis / D. D. Clarke And F. F. Nord From The Department Of Organic Chemistry And Enzymology, Fordham University, New York, New York, Donald Dudley Clarke Phd, Friedrich F. Nord

Chemistry Faculty Publications

After studying the effect of various substrates and also of certain enzyme inhibitors on the rate of formation of radicinin by Sterad, it is suggested that the carbohydrate molecule is utilized intact in the biosynthesis of radicinin


Ultraviolet Absorption Spectra Of Derivatives Of 2,3,5- And 2,4,5-Trihydroxyacetophenone / By D. D. Clarke And F. F. Nord, Donald Dudley Clarke Phd, Friedrich F. Nord Jan 1955

Ultraviolet Absorption Spectra Of Derivatives Of 2,3,5- And 2,4,5-Trihydroxyacetophenone / By D. D. Clarke And F. F. Nord, Donald Dudley Clarke Phd, Friedrich F. Nord

Chemistry Faculty Publications

No abstract provided.


The Chromatographic Purification Of Human Red Blood Cell Acetylcholinesterase, Richard P. Dunkley May 1954

The Chromatographic Purification Of Human Red Blood Cell Acetylcholinesterase, Richard P. Dunkley

Theses and Dissertations

A process of column chromatography of human erythrocyte acetylcholinesterase, using a cationic exchange resin, was investigated as a possible method for the primary partial purification of the enzyme on a large scale. The investigation was based, first; on a detailed study of the enzymatic stability to variation in hydrogen-ion and salt concentrations for periods of time extending to forty eight hours and, second; on an investigation of the degree of adsorption by the resin of the enzyme at various pH values within the pH range of enzyme stability. A method for the analysis of the enzyme activity of large numbers …


Biological Oxidation Of Copper Sulfide Minerals, Delmar Boyd Davis Dec 1953

Biological Oxidation Of Copper Sulfide Minerals, Delmar Boyd Davis

Theses and Dissertations

This work represents a study of the biological oxidation of copper sulfide minerals. The principal objective of the study was to determine the extent of bacterial oxidation on copper containing sulfide minerals. It was also desired to determine if the bacteria could oxidize copper sulfides in the absence of iron. A better understanding of the nitrogen requirements of the organisms was desired. Minerals used in this study were Bingham Canyon Float Concentrate, chalcopyrite, covellite, calcocite, bornite, tetrahedrite, and reagent grade copper sulfide. The bacteria used were obtained from the mine waters of Bingham Canyon, Utah. To study the problem the …


Radicinin: A New Pigment From Stemphylium Radicinum / D. D. Clarke F. F. Nord Department Of Organic Chemistry And Enzymology, Fordham University, New York 58, New York, Donald Dudley Clarke Phd, Friedrich F. Nord Jan 1953

Radicinin: A New Pigment From Stemphylium Radicinum / D. D. Clarke F. F. Nord Department Of Organic Chemistry And Enzymology, Fordham University, New York 58, New York, Donald Dudley Clarke Phd, Friedrich F. Nord

Chemistry Faculty Publications

No abstract provided.