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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.
71

Spatiotemporal tuning for position and velocity in primate primary motor cortex neurons /

Fellows, Matthew R. January 2005 (has links)
Thesis (Ph.D.)--Brown University, 2005. / Vita. Thesis advisor: John P. Donoghue. Includes bibliographical references (leaves 40-48, 78-80, 148-151, 229-231, 267-268). Also available online.
72

Deletion of the Bax gene severely impairs sexual behavior and modestly impairs motor function in mice

Jyotika, Jigyasa, January 2008 (has links)
Thesis (M.S.)--University of Massachusetts Amherst, 2008. / Includes bibliographical references (p. 33-40).
73

The effect of thyroxine 15ch on the growth and development of laboratory rats

Dieltiens, Ivy 16 April 2012 (has links)
M.Tech. / Thyroxine, a hormone produced by the thyroid gland, is known to be important for the growth and development of animals. A homoeopathic preparation of thyroxine added to the aquaria water of Rana temporaria tadpoles was shown to be capable of either slowing down or accelerating metamorphosis at different stages of development. In addition, ultra high dilutions of hormones (endogenous molecules) have been shown to have physiological effects on the immune system of mice. The aim of this study was to evaluate the effect of Thyroxine 15CH on the growth and development of laboratory rats. Forty male rats at the Central Animal Services of the University of Witwatersrand were administered either the placebo or Thyroxine 15CH (20 control and 20 treatment) at 16 days of age for 30 consecutive days. Body weight and linear measurements (head-body and tail lengths) were recorded from day 16 to 100 days of age, and rectal temperatures were recorded from day 58 to 100 days of age. Thereafter, rats were euthanased and the brain, heart and liver weighed, total thyroxine blood levels were determined, and bone mineral density and percentage body fat ascertained. Each control rat was paired with a treatment rat of the same litter by initial weight readings taken on day 16 to form 20 experimental couplets. The recorded data was analysed using the ANOVA for repeated measures and paired t-test for single measurements. Statistical analyses showed no significant differences between the control and treatment groups for all parameters measured (p > 0.05). In conclusion, Thyroxine 15CH did not have any statistically significant effect on the growth and development of laboratory rats. This research does not support the underlying philosophy of homoeopathy which is the Law of Similars, nor does it give evidentiary support to the theory of analogical communication as proposed by Lagache and Bastide. However, certain theories and explanations do exist to explain why no results were found, concluding that further research needs to be conducted in this field.
74

The effect of gonadotropin-releasing hormones (GnRH) I & II on sperm motility and acrosome status of the Vervet monkey (Chlorocebus aethiops) in vitro

De Villiers, Charon January 2006 (has links)
Masters of Science / Gonadotropin Releasing Hormone (GnRH) is a hypothalmic decapeptide, which regulates mammalian gonadotropin secretions by binding to specific, high affinity receptors in the pituitary. Two forms of GnRH (GnRH I and GnRH II) are expressed in the brain of human and some primates. Even though primates have been used extensively in a variety of investigations in relation to the role of GnRH in reproduction, there is no evidence of any research to investigate the direct effect of GnRH on primate sperm. / South Africa
75

Histopathological changes in male wistar rats maintained on a water-based sutherlandia frutescens extract

Wickens, Nicolas John January 2012 (has links)
In this study a standardized 46 week chronic drinking water toxicity protocol was used to elucidate the toxic potential of Sutherlandia frutescens (S. frutescens) using histopathologic, morphometric and transmission electron microscopic analysis. The histopathologic changes in the duodenum, heart, kidney, liver, lung, pancreas and spleen of male Wistar rats were evaluated. Fifty-four rats were randomly divided into four groups: Group 1 – Normal diet control (ND control), n=7, Group 2 – Normal diet + plant extract (ND + p), n=9, Group 3 – High fat diet control (HFD control), n=19Group 4 – High fat diet + p (HFD + p), n=19In the high fat group male Wistar rats were fed ±55 g/day of a specialised high fat diet over a 46 week period to induce obesity and an insulin resistant state. The treatment groups (groups 2 and 4) received a dose concentration of a tea extract of the S. frutescens plant in their drinking water daily. This study showed that the consumption of S. frutescens significantly reduces weight gain in male Wistar rats on a chronic high fat diet (p≤0.001 vs. HFD control group). S. frutescens appears to propagate periportal and centrilobular glycogen storage in rat hepatocytes in the experimental groups as exemplified by a significantly (p≤0.0001 vs. control groups) increased incidences of Periodic Acid Schiff (PAS) positive staining S. frutescens also reduced intracellular lipid accumulation as made evident by the significantly lower incidence of epicardial adipose tissue (EAT), hepatic steatosis and pancreatic interstitial fat. Obesity was associated with increased fibrotic lesions such as myocardial perivascular fibrosis, centrilobular hepatic fibrosis and pancreatic periductal fibrosis. Obesity associated hypertension contributed to the widespread and significant increase in the average lesion severity of arterial congestion in all organs in the HFD control group. Pulmonary infection was equally prevalent in all rats. Despite the complex histopathology in all groups, differences in the control groups, such as, the presence of a conservative polymorphonuclear leukocyte (PMNL) infiltration, substantial intra-alveolar oedema and focal arterial wall hypertrophy in the control groups was highly suggestive of Sendai viral infection. However histopathologic evidence, in the treatment groups, suggested chronic recurrent viral infection with superimposed Mycoplasma pulmonis (M. pulmonis) bacterial infection. The impact of advanced suppurative pulmonary infection was widespread and exemplified by increased lesion incidences of spontaneous murine progressive cardiomyopathy (MCP) and spontaneous chronic progressive nephropathy (CPN) among others. In conclusion S. frutescens administered for 46 weeks to male Wistar rats significantly lowered intracellular lipid accumulation and obesity associated myocardial, renal, hepatobiliary, pulmonary and pancreatic histopathology. Moreover, duodenal, cardiovascular, hepatobiliary, pulmonary, renal, pancreatic and splenic tissue did not show histopathologic evidence of direct plant extract associated toxicity or carcinogenicity.
76

An investigation of the organization of the cerebral cortex in the rat :: the use of horseradish peroxidase and fast blue to evaluate the columnar hypothesis.

Dodek, Anton Blaine 01 January 1984 (has links) (PDF)
No description available.
77

Auditory stimulation and control as sources of environmental enrichment for captive Rhesus monkeys.

Drewsen, Karla Hull 01 January 1985 (has links) (PDF)
No description available.
78

An Experimental Investigation to Determine Whether Change in the Visual Environment Following a Response Is Sufficient to Produce Learning in the Rat

Damm, Vernon J. January 1954 (has links)
No description available.
79

An Experimental Investigation to Determine Whether Change in the Visual Environment Following a Response Is Sufficient to Produce Learning in the Rat

Damm, Vernon J. January 1954 (has links)
No description available.
80

Mechanisms of enhancement and blockade by amphetamine in directly-stimulated rat skeletal muscle /

Meldrum, Michael Jay January 1980 (has links)
No description available.

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