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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.
1

Some effects of testosterone on cichlid fish, Cichlosoma bimaculatum (Linnaeus) /

Heitz, David Carl. January 1968 (has links)
Thesis (M.S.)--Oregon State University, 1968. / Typescript (photocopy). Includes bibliographical references (p. 57-59). Also available online.
2

Endogenous serum testosterone in man: ageing, the metabolic syndrome, functional decline and the role of supplementation

Haren, Matthew Timothy January 2005 (has links)
This thesis investigates the age - related decline in the various available measures and estimates of serum testosterone levels in men. Testosterone circulates predominantly bound with high affinity to sex - hormone binging globulin ( SHBG ) in plasma ( ~ 60 % ) and with lower affinity to albumin ( < 40 % ) ; approximately 1 - 2 % circulates unbound in plasma. It is the albumin - bound and free fractions ( termed " bioavailable testosterone " ) that are most likely to have biological effects on target tissues. This thesis reports the establishment, validation and derivation of normal ranges for an ammonium sulphate precipitation method for the measurement of bioavailable testosterone in serum. This method is in use by a number of laboratories at present including the laboratory of Professor John Morley at St Louis University with whom we collaborated. Testosterone has been shown, both cross - sectionally and longitudinally, to decline progressively beginning around the age of thirty. Total testosterone declines at approximately 0.4 % per year while bioavailable and free testosterone decline at approximately 1.2 % per year. The mechanisms that may be responsible for this include age - related changes to the hypothalamic - pituitary - testicular axis, increased SHBG levels, environmental factors, medication and chronic illness. This decline may contribute to a multitude of physiological, psychosexual and cognitive changes associated with ageing in men. This thesis crosssectionally examines the possible determinants of the various fractions of serum testosterone and the associations with various physical, psychosexual and lifestyle variables and with chronic disease and medication use. These cross - sectional data were generated from the Florey Adelaide Male Ageing study, which randomly recruited 568 men from the north and west suburbs of Adelaide, between August 2001 and August 2002. Moreover, this thesis includes a randomised controlled trial of testosterone replacement therapy in men aged 60 years and over with low - normal testosterone levels at baseline, recruited by newspaper advertisement. The goals of testosterone replacement therapy might be to prevent osteoporosis, age related frailty and falls, and to maintain optimal physical, sexual, emotional and cognitive health during the ageing process. This intervention study focused on the effect of treatment on body composition and muscle strength, symptoms of testosterone deficiency, visuospatial cognition, mood, wellbeing and quality of life. Finally, preliminary work was initiated to develop an in vitro bioassay for the measurement of serum testosterone bio - action. This was done using a transient transfection protocol in cultured cells, where androgen receptor and androgen response elements were introduced into the cells, subsequently treated with testosterone containing media and the amplitude of response quantified using a dual - luciferasereporter assay. In summary, this thesis discusses the issues with the measurement of testosterone in plasma and the factors that determine the concentration of the various fractions of testosterone in plasma. A cross - sectional study, using random recruitment procedures was used to investigate associations between testosterone levels and health - related - factors and finally a randomised - controlled - trial of testosterone replacement in ageing men with low - normal testosterone levels is reported. Throughout the thesis, the following themes are common ; body composition, physical function and strength, sexual function, lower urinary tract symptoms and the prostate, visuospatial cognition, mood, quality - of - life and wellbeing. / Thesis (Ph.D.)--Medical School, 2005.
3

Use of non-specific and specific interactions in the analysis of testosterone and related compounds by capillary electromigration techniques /

Amundsen, Lotta K. January 1900 (has links) (PDF)
Thesis (doctoral)--University of Helsinki, 2008. / Includes bibliographical references. Also available on the World Wide Web.
4

Testosterone and aging in Chinese men

Chu, Leung-wing. January 2008 (has links)
Thesis (M. D.)--University of Hong Kong, 2008. / Includes bibliographical references (leaf 119-138) Also available in print.
5

Endogenous serum testosterone in man: ageing, the metabolic syndrome, functional decline and the role of supplementation

Haren, Matthew Timothy January 2005 (has links)
This thesis investigates the age - related decline in the various available measures and estimates of serum testosterone levels in men. Testosterone circulates predominantly bound with high affinity to sex - hormone binging globulin ( SHBG ) in plasma ( ~ 60 % ) and with lower affinity to albumin ( < 40 % ) ; approximately 1 - 2 % circulates unbound in plasma. It is the albumin - bound and free fractions ( termed " bioavailable testosterone " ) that are most likely to have biological effects on target tissues. This thesis reports the establishment, validation and derivation of normal ranges for an ammonium sulphate precipitation method for the measurement of bioavailable testosterone in serum. This method is in use by a number of laboratories at present including the laboratory of Professor John Morley at St Louis University with whom we collaborated. Testosterone has been shown, both cross - sectionally and longitudinally, to decline progressively beginning around the age of thirty. Total testosterone declines at approximately 0.4 % per year while bioavailable and free testosterone decline at approximately 1.2 % per year. The mechanisms that may be responsible for this include age - related changes to the hypothalamic - pituitary - testicular axis, increased SHBG levels, environmental factors, medication and chronic illness. This decline may contribute to a multitude of physiological, psychosexual and cognitive changes associated with ageing in men. This thesis crosssectionally examines the possible determinants of the various fractions of serum testosterone and the associations with various physical, psychosexual and lifestyle variables and with chronic disease and medication use. These cross - sectional data were generated from the Florey Adelaide Male Ageing study, which randomly recruited 568 men from the north and west suburbs of Adelaide, between August 2001 and August 2002. Moreover, this thesis includes a randomised controlled trial of testosterone replacement therapy in men aged 60 years and over with low - normal testosterone levels at baseline, recruited by newspaper advertisement. The goals of testosterone replacement therapy might be to prevent osteoporosis, age related frailty and falls, and to maintain optimal physical, sexual, emotional and cognitive health during the ageing process. This intervention study focused on the effect of treatment on body composition and muscle strength, symptoms of testosterone deficiency, visuospatial cognition, mood, wellbeing and quality of life. Finally, preliminary work was initiated to develop an in vitro bioassay for the measurement of serum testosterone bio - action. This was done using a transient transfection protocol in cultured cells, where androgen receptor and androgen response elements were introduced into the cells, subsequently treated with testosterone containing media and the amplitude of response quantified using a dual - luciferasereporter assay. In summary, this thesis discusses the issues with the measurement of testosterone in plasma and the factors that determine the concentration of the various fractions of testosterone in plasma. A cross - sectional study, using random recruitment procedures was used to investigate associations between testosterone levels and health - related - factors and finally a randomised - controlled - trial of testosterone replacement in ageing men with low - normal testosterone levels is reported. Throughout the thesis, the following themes are common ; body composition, physical function and strength, sexual function, lower urinary tract symptoms and the prostate, visuospatial cognition, mood, quality - of - life and wellbeing. / Thesis (Ph.D.)--Medical School, 2005.
6

Characterization of value nutritions 5-androstenediol product and its proliferative effects on the LNCaP cell line

Grouf, Jaime L. January 2007 (has links)
Thesis (M.S.) -- Worcester Polytechnic Institute. / Keywords: Nutraceuticals; Prostate cancer; 5-Androstenediol. Includes bibliographical references (p.71-76).
7

Padronizacao da dosagem de didrotestosterona apos cromatografia em celite

LANDO, VALERIA S. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:37:06Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:56:35Z (GMT). No. of bitstreams: 1 04606.pdf: 976500 bytes, checksum: 8d50374f874896beb8118294c19df921 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
8

Padronizacao da dosagem de didrotestosterona apos cromatografia em celite

LANDO, VALERIA S. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:37:06Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:56:35Z (GMT). No. of bitstreams: 1 04606.pdf: 976500 bytes, checksum: 8d50374f874896beb8118294c19df921 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
9

Testosterone replacement therapy

Vrolyk, Michael 08 April 2016 (has links)
Physicians and scientists have suspected that the testes secrete a substance into the body that causes male secondary sexual characteristics for hundreds of years. However, testosterone was not synthesized until 1935 and it was not until the 1940's when scientists could accurately measure the amount of this hormone in the blood. Since then, scientists have been able to make correlations between the levels of testosterone in the body and men's health Scientists have long observed higher levels of testosterone to be associated with an increase in levels of Hematocrit (Hct). As a result, Testosterone Replacement Therapy (TRT) has been used to treat anemia associated with chronic diseases. In recent years, prescription sales for testosterone have sky rocketed due to new clinical uses such as androgen deficiency in older men. In fact, the rate of prescription for testosterone products has increased by over 170% in the previous five years. Long-term data shows that the level of testosterone in the male body begins to decrease at about the age of 30. As the life expectancy of the general population continues to increase, TRT may be a viable option for older men with low testosterone to increase the quality and duration of life. However, an increase in Hct continues to be a major side effect of TRT. New research is beginning to make clear the mechanism by which testosterone affects erythropoeisis. New research suggests TRT suppresses hepcidin and leads to an increase in the rate of iron (Fe) retention in red blood cells (RBCs). Inter-individual differences in the pharmacogenetic effects of TRT have been observed. In the future TRT could be genetically tailored based on the individuals DNA. In this case, the optimal dose of testosterone can be given to maximize benefits and reduce side effects. Here, the risks and benefits associated with TRT and a review of the updated Clinical Guidelines for its use will be presented. The effects of TRT on erythropoeisis will be investigated via a review of the literature. The main objective of this review is to provide a general understanding of TRT and a major side effect of its use, excessive erythropoeisis.
10

The Hypothalamic-Pituitary-Gonadal Axis In Male Psychiatric Inpatients

Brdaroska, Bilyana January 2006 (has links)
Doctor of Philosophy / A large number of neuroendocrine studies indicate a possible relationship between the Hypothalamo-Pituitary-Gonadal (HPG) axis and major depressive illness in men. This observation is not surprising, considering the similarities between the symptom profiles of depression and hypogonadism. However, owing to the strong likelihood that a number of other demographic, clinical and treatment covariates may potentially obscure a possible relationship between HPG and depression, studies in this area have produced somewhat inconsistent results. The main objective of the present study was to investigate the relationship between depression and HPG hormone levels in a population of hospitalised men. Another objective was to examine the relationship of a number of demographic, behavioural, clinical and treatment variables with HPG hormone levels and depression. METHOD: Serum hormones of the HPG axis (Luteinizing Hormone (LH), Follicle Stimulating Hormone (FSH), Free Testosterone (free T), Total Testosterone (total T) and Sex Hormone Binding Globulin (SHBG)) were compared between fifty-two male patients with Major Depressive Disorder (mean age = 42.04; SD = 14.1) and twenty-five male patients with other psychiatric conditions (mean age = 40.72; SD = 13.8) on admission into hospital. In addition, to elucidate the possible relationship between clinical outcome of depression and gonadal function, HPG parameters were measured in patients with depression 3 to 6 months following discharge. Based on their HDRS (Hamilton Depression Rating Scale) score, patients were categorised as remitters and non-remitters. Demographic, behavioral, clinical and treatment variables were also examined as possible correlates of hormone levels. RESULTS: Comparison between patients with depression and patients with other diagnoses indicated a significantly lower free T and total T in patients with depression. There were no differences in other hormone parameters between the two diagnostic groups. Correlational analyses indicated significant negative relationships between free T and total T and severity as well as duration of depression. Age was inversely correlated to both free T and total T, whereas BMI was negatively correlated with Total T and SHBG. There was a positive relationship between Total T as well as Free T and measures of sexual dysfunction. While no difference in hormone parameters was observed as a function of psychotic features, patients with melancholic features exhibited significantly lower levels of free T and total T compared to patients with no melancholic features. In the multiple regression analyses, age, duration and severity of depression were the strongest predictors of both free and total T. In separate regression analyses somatic features, over and above other features of depression were found to account most in the variability in free T and total T. Longitudinal analysis revealed significantly higher free T and total T levels on follow-up compared to baseline in the patients who remitted. There was no significant change in any of the hormones studies in the non-remitting group. CONCLUSION: The main findings of the present study support previous results that both total and free testosterone levels are lower during depression and that concentrations of free T and total T parallel changes in severity of depressive symptomatology. Further investigations into the mechanism for this observation, and perhaps examinations of testosterone supplementation for treatment of depression are in order.

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