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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.
281

Analgesic effect of paeoniflorin in rats with visceral hyperalgesia induced by neonatal maternal separation

Zhang, Xiaojun 01 January 2008 (has links)
No description available.
282

A phenomenological investigation into the psychoanalytic psychotherapist's experience of identifying, differentiating and processing the patient's transference-based and reality-oriented reactions

Danilewitz, Larry Mark January 1993 (has links)
The aim of this study was to describe the psychoanalytically-oriented therapist's experience of identifying, differentiating and processing the patient's transference-based and reality-oriented reactions. In order to investigate the therapist's lived experience of being receptive to the total communication of the patient in the analytic situation, the researcher adopted the empirical phenomenological method. This descriptive and intuitive method grounded the researcher in the concreteness of the everyday life-world of the therapist, and enabled him to explicate the therapist's immediate, pre-theoretical experiences of his patient. The appropriate central research question, formulated to elicit the experience of this phenomenon, emerged through the process of enquiry during the pilot study. Thirteen experienced, psychoanalytically-oriented psychotherapists were interviewed and the five protocols considered most revelatory of the phenomenon under investigation were analyzed in detail. The remaining eight protocols were used to illuminate central themes and to clarify areas of uncertainty during the phase of formal explication. The central findings revealed that the oscillating process of the therapist as he shifts from being immersed in the world of his patient to being in a position of observation and self reflection is the fulcrum around which he evaluates the nature of his patient's communications. During this ongoing process of discrimination, living in duality, the therapist comes to experience himself as a patient scrutinized by his own and his patient's confrontations. His journey of disentanglement, the endeavour to differentiate his responses from his patient's actions, is dependent on his ability to engage in honest selfreflection and to access his pre-theoretical and articulated cognitions of his patient. This allows him to acknowledge his own role in what has unfolded interpersonally and to appropriate his previously denied feelings for and attitudes towards his patient, a prerequisite for the accurate and full appraisal of the nature of his patient's communications. Forsaking fixed judgements, the therapist becomes open to the confluence between the reality-oriented responses and transference-based reactions of his patient. This salient discovery, when dialogued with the literature, reinforced the theories of Greenson and Langs that not all the interactions between the patient and the analyst/therapist are transference-based and that it is therefore imperative that the analyst/therapist reflect on his participation in the analytic situation.
283

Nutrient supplementation and secondary metaolites in melanoma cells

Stoll, Karin Elisabeth January 1994 (has links)
Considerable interest exists with regard to the putative therapeutic role of ascorbic acid in various conditions. A condition which has received much attention is cancer, as it is reported that ascorbic acid may be a prophylactic against cancer development. However, the actual involvement of ascorbic acid, an oxidizing/reducing agent, in the development and progression of tumours is presently a subject of much speculation. This study initially addressed the effect of ascorbic acid supplementation over a nutritional concentration range (0 - 100 μg/ml) on the in vitro growth of non-malignant LLCMK and malignant B16 cells. Ascorbic acid supplementation of these two cell types resulted in an overall decrease in the growth of both types of cells. The actual inhibitory mechanism of ascorbic acid on cell growth was not clear. Further study attempted to define and explain a mechanism responsible for this effect. Ascorbic acid has a role in the maintenance of tissue integrity and host defences, thus providing a rational basis for examining its relationship to cancer. Ascorbic acid is lcnown to be essential for the structural integrity of the intercellular matrix of the cells, the latter being a complex aqueous gel containing, amongst other compounds, fats and prostaglandins. Fats and prostaglandins have diverse effects on. membrane stability, enzyme activity and secondary messengers within cells. Hence, this study investigated the effect of ascorbic acid supplementation on certain enzymes and secondary metabolites within the cells, which had the potential to be involved in the control of cell growth. Throughout this study, emphasis was placed on the Bl6 melanoma cells as ascorbic acid supplementation did not significantly affect levels of secondary metabolites within the non-malignant LLCMK cells. Ascorbic acid supplementation of the B16 cells resulted in significant increases in adenylate cyclase activity and cyclic adenosine monophosphate levels, witb a significant decrease in Bl6 cell growth in that particular experiment. As cyclic adenosine monophosphate has a regulatory role in the cell cycle, this study suggested that the inhibitory effect of ascorbic acid supplementation on cell growth was mediated tbrough a final effect provided by the second messenger, cyclic adenosine monophosphate. However, clarification of tbe mechanism of tbe effect of ascorbic acid on adenylate cyclase activity was required. Hence, a further study investigated prostaglandin E₂ levels, as tbese affect adenylate cyclase activity. Prostaglandin E₂ levels were also found to be inversely related to Bl6 cell growth with ascorbic acid supplementation. It thus appeared tbat adenylate cyclase activity was dependent on prostaglandin E₂ levels in the B16 cells, and further study showed that tbis was indeed the case. Here, higher levels of prostaglandin E₂ supplementation of the Bl6 cells inhibited cell growth significantly and also significantly increased adenylate cyclase activity. Arachidonic acid is the precursor of prostaglandin E₂. In the presence of ascorbic acid supplementation, the percentage arachidonic acid composition of the Bl6 cells was inversely correlated with cell growth. Hence, prostaglandin E₂ levels in ascorbic acid supplemented B16 cells appeared dependent on tbe amount of precursor present. This was confirmed when Bl6 cells were supplemented with arachidonic acid. The latter had an inhibitory effect on Bl6 cell growth and also stimulated prostaglandin E₂ production. The cause of tbe inverse relationship between B16 cell growth and arachidonic acid composition with ascorbic acid supplementation was furtber investigated and found to be dependent on tbe uptake of arachidonic acid and other essential fatty acids from tbe medium. The enzymes phospholipase A₂ delta-5 and delta-6-desaturase, and elongase which could influence arachidonic acid levels were not affected to any extent by ascorbic acid supplementation and therefore did not influence the inverse relationship between B16 cell growth and arachidonic acid. Hence, it can be concluded that the effect of ascorbic acid supplementation on the BI6 cells is mediated, in part at least, by cyclic adenosine monophosphate. However, this is not the result of a direct effect of ascorbic acid supplementation. The initial effect of ascorbic acid supplementation concerns fatty acid - in particular arachidonic acid - uptake from the medium, with subsequent cascade effects On secondary metabolites, ultimately affecting the cellular levels of cyclic adenosine monophosphate.
284

The effect of 6-Methoxy-2-Benzoxazolinone (6-MBOA) on indoleamine regulation and its possible role in depression

Tanda, Sindiswa Eunice January 2000 (has links)
Tryptophan is an essential amino acid that is obtained from the diet. Approximately 98 % of ingested tryptophan is metabolized by the enzyme tryptophan 2,3-dioxygenase (TDO). The metabolism of tryptophan by TDO is an important determinant of tryptophan bioavailability to the brain for serotonin (5-HT) biosynthesis, an essential amine in affective disorders such as depression. Studies done on circadian rhythmicity of the enzyme activity have shown that, TDO activity is high during the scoto-phase (dark-phase), which is attributable to the de novo enzyme synthesis that occurs during this phase. 6-Methoxy-2-benzoxazolinontr-(6-MBOA), a structural analogue of melatonin (aMT) was shown to inhibit TDO activity in both the photo-phase (light-phase) and the scoto-phase with greater potency during the light-phase. Further studies were directed at demonstrating the effects of 6-MBOA on the brain tryptophan hydroxylase (TH) activity, which is a rate limiting enzyme in 5-HT biosynthesis and subsequently on 5-HT levels. The findings showed that, 6-MBOA induces TH activity with a concomitant rise in brain 5-HT levels. The blockade of 5-HT re-uptake into the presynaptic neuron leads to an increase in 5-HT available for the stimulatory action of 5-HT receptors. An attempt to establish whether the administration of 6-MBOA would block the binding of 5-HT to receptors on the synaptosomal membrane showed that 6-MBO A only inhibits the binding of 5 -HT at specific concentrations. In view of the positive effects imposed by 6-MBOA on brain 5-HT levels, urinary 5-hydroxyindole acetic acid (5-HIAA) excretion was measured before and after treatment with 6-MBOA. 5-HIAA excretion was found to be significantly increased after 6-MBOA treatment. Extensive research on the biosynthesis of pineal metabolites has been conducted in the past two decades. The pineal metabolites are synthesized from the precursor tryptophan. In order to obtain an overall picture of the effect of6-MBOA on pineal indole metabolism, an organ culture technique was employed. The results obtained showed that although 6-MBOA administration to rats caused a significant increase in aMT production, there was an insignificant increase in NAS production. This is an immediate precursor of aMT. Other pineal indoles were not affected at all by 6-MBOA administration. Furthermore, the production of pineal NAS and aMT showed an inter-individual variation with some animals producing very high, some very low and some produced average levels of these two metabolites in both photo and scoto-phase experiments. A study undertaken to investigate the circadian rhythm in endogenous aMT production using the competitive ELISA technique showed a clear pattern with high levels of aMT produced during the dark-phase and low levels ofaMT produced during the light-phase. Furthermore, the administration of6-MBOA to rats lead to a significant rise in endogenous aMT production.
285

An investigation into the neuroprotective properties of curcumin

Daniel, Sheril January 2003 (has links)
An increasing number of studies show that nutritional antioxidants such as vitamin E and polyphenols are capable of blocking neuronal death in vitro and may have therapeutic properties in animal models of neurodegenerative diseases including Alzheimer’s and Parkinson’s diseases. In the present study, the neuroprotective ability of one such polyphenolic antioxidant, curcumin, was investigated. Curcumin is the yellow curry spice derived from turmeric, and is widely used as a dietary component and herbal medicine in India. Most neurological disorders are postulated to have an oxidative or excitototoxic basis. Thus the effects of curcumin on oxidative stress in the rat brain were investigated. Curcumin, administered to the rat in vivo and in vitro, was able to exert protective effects on oxidative damage in the brain, induced by cyanide, a mitochondrial inhibitor. Curcumin also offered protection against quinolinic acid induced lipid peroxidation, and this protection was extended to lipid peroxidation induced by metals such as lead and cadmium in the rat brain. Experiments conducted on the pineal gland revealed an increased production of the neuroprotective hormone melatonin in presence of curcumin in vivo. The hippocampus is functionally related to vital behaviour and intellectual activities and is known to be a primary target for neuronal degeneration in the brains of patients with Alzheimer’s disease. Histological studies were undertaken to assess the effects of curcumin on lead induced toxicity on the rat hippocampus, the results of which show that curcumin affords significant protection to the hippocampus of the lead treated rats. This study also sought to elucidate possible mechanisms by which curcumin exerts its neuroprotective capabilities. Curcumin was found to inhibit the action of cyanide on the mitochondrial electron transport chain, one of the most common sources of free radicals. Electrochemical, UV/VIS and Infrared spectroscopy were used to characterise interactions between curcumin and the metals lead, cadmium, iron (II) and iron (III). Curcumin was shown to directly chelate these metals with the formation and isolation of two new curcumin complexes with lead, and one complex each with cadmium and iron (III). These results suggest chelation of toxic metals as a mechanism of neuroprotection afforded by curcumin. The need for neuroprotective agents is urgent considering the rapid rise in the elderly population and the proportionate increase in neurological disorders. The findings of this study indicate that curcumin, a well-established dietary antioxidant, is capable of playing a bigger role in neuroprotection, which needs to be further explored and exploited.
286

A gas chromatographic study of oils from some Agathosma species (family Rutaceae)

Persicaner, Peter Henry Robert 13 November 2013 (has links)
From Introduction: Buchu leaf is a very widely used household medicine in South Africa, and is usually administered in the form of a brandy tincture or a vinegar, known as "buchu brandy" and "buchu vinegar" respectively. These preparations have a great reputation in curing diseases of the kidney and urinary tract, and in addition are employed as local applications to bruises, and for the relief of rheumatic pains. We owe its introduction into medicine to the Hottentot, who gave the name "buchu" or "bookoo" to any aromatic herb or shrub which they found suitable for use as a dusting powder.
287

A study of the efficacy of manipulation as opposed to cryotherapy and manipulation in the treatment of tension-type headache

Angus, Antony Keith January 1997 (has links)
A dissertation submitted in partial compliance with the requirements for a Master's Degree in Technology: Chiropractic, Technikon Natal, 1997. / The purpose of this investigation, was to determine what role cryotherapy plays in conjunction with manipulation headaches. / M
288

The efficacy of detuned ultrasound compared to proprioceptive neuromuscular facilitation of the gluteal musculature both used in conjunction with manipulation in the treatment of sacroiliac syndrome

Paton, Jaqueline January 2001 (has links)
A dissertation presented in partial compliance with the requirements for the Master's Degree in Technology: Chiropractic, Technikon Natal, 2001. / The purpose of this study was to determine the relative efficacy of chiropractic manipulation used in conjunction with detuned ultrasound over the gluteal muscles compared to manipulation used in conjunction with proprioceptive neuromuscular facilitation stretching of the gluteal muscle group in the treatment of sacroiliac syndrome. It was hypothesised that both treatment groups would be effective in the treatment of sacroiliac syndrome but that manipulation used in conjunction with proprioceptive neuromuscular facilitation of the gluteal musculature would be more effective than manipulation used in conjunction with detuned ultrasound, in terms of subjective and objective clinical findings. / M
289

Efficacy of two medical plant extracts and metformin in the prevention of diet induced fatty liver

Tshidino, Shonisani Cathphonia January 2014 (has links)
Non‐alcoholic fatty liver diseases (NAFLD) is manifested in the absent of alcohol abuse. This disease is the major cause of liver failure and death among adults and children worldwide, including South Africa. Its increasing prevalence urges the need of therapeutic intervention. The main objectives of this study were to investigate the following: (1) The effect of 38.9% high fat diet (HFD)‐induced insulin resistance and fatty liver in male Wistar rats, (2) The efficacy of aqueous extracts from Sutherlandia frutescens leaves and Prunus africana bark and metformin in the treatment of HFDinduced insulin resistance and fatty liver. Male Wistar rats were fed on HFD (the HF group) or normal rat chow (the LF group) for 12 weeks. Even though the HFD‐fed rats had developed insulin resistance by week 12, fatty liver developed by week 16. After week 12, the HF group was divided into four groups of 6‐7 rats each and three of those groups were gavaged with either 0.125 mg P. africana extract/kg bwt/day (the HF+Pa group) or 50 mg S. frutescens extract kg bwt/day (the HF+Sf group) or 16 mg metformin/ kg bwt/day (HF+Met group), while kept on the same diet for an additional of 4 weeks, to investigate whether two medicinal plant extracts and metformin can prevent HFD to induce fatty liver or not. After 16 weeks, the liver histological images revealed that the HF group developed fatty liver in the form of both microsteatosis and macrosteatosis. Fatty liver was confirmed by significant increased liver total lipid (TL) and activities of glucose‐6‐phosphate dehydrogenase (cG6PD) and xanthine oxidase (XO), mitochondrial NADH oxidase (mNOX) and by a decrease (P<0.05) in the activities of the homogenate superoxide dismutase (hSOD) and mitochondrial complex II in the HF group, when compared to the LF group. Since the activities of mCS and cACL enzymes were not changed in the HF group, hence increased cG6PD activity in the HF group indicates that there was increased NADPH demand for lipid accumulation from activated NEFAs taken up by the liver from circulation and for maintenance of the NADPH‐dependent antioxidants and oxidants, respectively. The obtained data also show that mitochondria of the HFD‐fed rats adapted to an increase in energy availability, thereby compensation through decreasing complex II activity, to allow electron flux from β‐oxidation to respiratory chain in the HF group. Liver TL content was significantly decreased in the rats treated with metformin and P. africana extract, but not in the rats treated with S. frutescens when compared to the HF group (P < 0.05). However, the TL content remained >5% per liver weight in all treated groups. The present study demonstrates that these two plant extracts and metformin have different glucogenic and lipogenic effects from that presented by HFD alone when compared to the LFD alone. In conclusion, metformin and P. africana extract can attenuate HFD‐induced fatty liver without changing the dietary habits. Hence S. frutescens extract is less effective in the prevention of HFD‐induced fatty liver. A change in the dietary habits is recommended to be considered during the use of these three remedies in the treatment of HFD‐induced insulin resistance and fatty liver. All three treatments enhanced antioxidant capacity, and may improve insulin resistance and fatty liver mediated by the present HFD through different mechanism of actions in the liver.
290

A systematic review of the effectiveness of animal-assisted interventions

Badenhorst, Estelle January 2014 (has links)
There is a global increase in research on the benefits of animals and the value of incorporating them into interventional practices. This is referred to as animal-assisted interventions. Due to the novelty of this type of intervention and the accompanying complexity of variables, a need exists to explore the various aspects within these interventions. Looking specifically at animal-assisted interventions within the mental health field, this study focuses on the psycho-therapeutic value of companion animals, such as dogs and cats. The primary aim of this study was to identify the mechanisms through which an animal-assisted intervention exerts its influence. A secondary aim was to indentify salient methodological aspects within the included studies. A systematic review of existing literature was undertaken to explore these factors. Each study was appraised against specific inclusion and exclusion criteria and themes were extracted. The data was synthesised, integrated and discussed in relation to previously conducted studies in relevant fields. Six themes emerged from the systematic review. These included enhanced comfort, the living nature of animals, physical contact, adjunctive nature, an affinity for animals, as well as methodological considerations. Based on these emergent themes conclusions were drawn as to the psycho-therapeutic influences of companion animals. This may serve as informative knowledge regarding animal-assisted interventions for practitioners seeking additional methods to reach treatment goals. Information is also provided for researchers interested in the field, particularly methodological considerations, before embarking on a study of animal-assisted intervention efficacy.

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