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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.

Effect of some convulsive agents on cerebral glucose-amino acid interrelationships in vitro.

Haber, Andrew. B. January 1963 (has links)
The introduction of the tissue slice technique by Warburg and his associates markedly facilitated in vitro metabolic studies. In 1924 Warburg reported that rat brain cortex slices incubated in a glucose-Ringer medium yielded an oxygen quotient (Qo2) of 10.7. Though higher rates have been recorded for the Qo2 of brain cortex slices in normal physiological media, these values have invariably been round to be lower than those calculated for the brain in vivo. Elliott estimating the respiratory rates of the whole brain invitro found that they approximate the rates observed in vivo in conditions of diminished functional activity.

The metabolism of tritium-labelled folic acid in man.

Johns, David. G. January 1963 (has links)
The beginning of our knowledge of the vitamin folic acid dates back to the discovery of Wills (1) in 1931 that the macrocytic anemia of pregnancy frequently observed in the tropics responded to oral administration of concentrated extracts of autolysed yeast. This tropical anemia resembled classical Addisonian pernicious anemia in that the bone marrow exhibited megaloblastic changes, but differed from true pernicious anemia in that achlorhydria and neurological changes were absent. A considerable advance was made in the characterization of the unknown hematopoietic factor when it was found by Wills and Stewart (2) that a similar syndrome could be induced in monkeys by feeding a diet similar to that common in those areas of India where the disease was frequent.

On the equivalence, content and state of gamma-aminobutyric acid and factor I in mammalian brain.

Lovell, Richard. A. January 1963 (has links)
The aim of neurochemistry, or the biochemistry of the nervous system, is to discover the nature or those substances involved in the changes which enable nerve cells to accomplish their unique function as highly specialized conducting cells, to study the metabolism or these substances and to determine how and to what extent they regulate these functional changes. Hence the aim or neurochemical research on gamma-aminobutyric acid is simply to further our understanding of the neuron at the molecular level and of the way in which active molecules like gamma-aminobutyric acid regulate, or are involved in, neuronal function.

The influence of electrical stimulation on the ACh-like activity of the cat’s superior cervical ganglion and the isolated frog’s heart.

Proulx, Lucille. M. January 1963 (has links)
Usually, attempts to demonstrate the physiological function of a substance are made after this substance has been shown to be present in the animal body or tissue. In the case of acetylcholine (ACh), the sequence of events was quite different, for, it will be seen that the physiological role of ACh had been suggested long before its discovery in animal tissue. It is generally believed that two different physiological events occur innerve activity: a) conduction, i.e. propagation of the nerve impulse in the nerve fibers and, b) transmission, a biochemical process that occurs at nerve endings or synapses. The fundamental findings on which these concepts were based can be traced as far back as 1843.

Absorption and metabolism of carbohydrates by the small intestine.

Sahagian, Benjamin. January 1963 (has links)
It was not until the year 1839 that Theodor Schwann, a professor of anatomy and physiology at Louvain, Germany, advanced his cell theory in which he postulated that all living matter is made up of cells. Modem biochemistry has no quarrel with this concept and accepts the cell as the fundamental organized unit of all living matter. The living cell is composed of a number of intracellularly located elements which are surrounded by an extremely thin and delicate membrane. This membrane is a complex and fragile structure which is and must be considered an integral part of the cell as a living unit. Cellular architecture or structural compartmentation within the cell is also achieved almost entirely by means of individual membranes surrounding each of the intracellularly located parts.

The influence of narcotic and convulsant drugs on acetylcholine-like substances in brain.

Samad, Roushan. A. January 1963 (has links)
Interest in acetylcholine (ACh) as a chemical transmitter in the central nervous system was developed many years ago when attempts were made to determine the mechanism of transmission of impulses occurring (a) across ganglionic synapses and (b) from motor nerve endings to the motor endplates of skeletal muscle. Although ACh was synthesized in 1867 (1) and Elliott in 1904 (2) firmly suggested the concept of humoral transmission when he found marked functional similarities between the effects of sympathetic nervous stimulation and that of adrenaline action, it was not until 1906, that Hunt and Taveau (3) proved ACh to be a nerve depressor.

Measurement of homovanillic acid in human urine.

Sankoff, Irwin. January 1963 (has links)
Homovanillic acid has been shown by several investigators to be a constituent of normal human urine. In certain disease states, the urinary level of homovanillic acid is altered. This tact may be used as a criterion for clinical diagnosis of these diseases. Several method are available for measuring homovanillic acid, but they are relatively involved and costly procedures. The purpose of this study was to determine a rapid method which could be used routinely for the clinical measurement of homovanillic acid. Dopamine and its metabolite, 3, 4-dihydroxyphenylacetic acid, have been shown in Dr. Sourkes' laboratory to be abnormal in certain diseases. Another metabolite of these substances, homovanillic acid, has also been found in elevated amounts in some diseases.

Studies on the intermediary metabolism of glycine.

Selvaraj, Ratnam. J. January 1963 (has links)
Glycine was the first amino acid shown by isolation to be present in a protein hydrolysate (Braconnot, 1820). Besides incorporation into proteins, peptide hormones and glutathione, the carbon atoms of glycine appear in other amino acids like serine and creatine, glycocholic acid, hippuric acid, purine and porphyrin rings. The methylene carbon atom of the glycine molecule also contributes significantly to the one carbon pool. Thus, although structurally the simplest amino acid, the metabolism of glycine presents a complex picture. If carbohydrate and lipids are considered as fuels for the metabolic furnace, proteins may be regarded as forming not only the structural frame work, but also the gears and leavers of the machinery.

Uptake of ascorbic acid by adrenals and brain and the action of steroid hormones and ACTH.

Sharma, Shail. K. January 1963 (has links)
During the past three decades, following the isolation of ascorbic acid from bovine adrenal glands (1), there have been many investigations concerning the possible role of this vitamin in adrenal function. The elucidation of the mechanism and significance of ACTH (adrenocorticotrophic hormone) induced depletion of ascorbic acid is still a major problem in adrenocortical physiology. Ascorbic acid occurs in two forms, one being the oxidation product of the ether. Both forms are biologically active. They are water soluble, insoluble in organic solvents, and unstable when exposed to oxygen, light, alkalies and certain metals. The most prominent chemical property of ascorbic acid is its ready oxidation to dehydroascorbic acid, which is catalyzed by small concentrations of metal ions.

Antigenicity of caffeic acid- and chlorogenic acid-protein conjugates.

Tenenhouse, Harriet. R. January 1963 (has links)
When an animal receives one or more parenteral injection of certain foreign materials - proteins, red blood cells, tissue extracts from another species, bacteria or bacterial products - there generally appears in the serum, within a few days, a substance which possesses the unique property of reacting with the material injected (1). This serum component is termed antibody and the material which stimulated its production is called antigen. The animal which has formed antibodies is said (by convention) to be immunized. The presence of antibodies in the serum of immunized animals may be recognized by the occurrence of certain characteristic reactions such as precipitation, agglutination, and complement fixation.

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