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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.
41

The pharmacological effects of Clivia miniata on isolated rat uterus and ileum

Veale, Denise Joy Hall 29 April 2013 (has links)
Thesis (M.Sc. (Med.))--University of the Witwatersrand, Faculty of Health Sciences, 1991
42

Richness and diversity of alien ethnomedicinal plant taxa used and sold for traditional medicine in South Africa

Wojtasik, Ewa Mariola 04 March 2014 (has links)
In South Africa, indigenous plant species are used and traded for traditional medicine (muthi) and so are alien plant species. A literature review of 40 previous studies and survey work at various outlets, including muthi markets and muthi shops in Johannesburg, Durban and Pretoria, found that 320 alien plant species are used and/or sold for traditional medicine in South Africa. Fifty three of the 320 species were found to have weed and/or invader status. Surveys at Faraday and Warwick muthi markets in Johannesburg and Durban respectively as well as muthi shops in Johannesburg, Durban and Pretoria were conducted from October 2010 to February 2011. The following aspects regarding the plant material traded were recorded: the differences in the number of volumes traded; the differences in the number of alien species sold in the markets and shops (and also in Indian and Black-owned shops); the source and origins of these and the viability of propagules sold in the muthi trade. The surveys found that 49 alien plant species were sold and approximately 87 x 50kg-size bags of alien plant material was present in the markets and shops during the time of the survey. Muthi shops sold more than double the number of alien plant species than were sold in the markets and the same result was found for Indian versus Black-owned shops. Alien species were either harvested in South Africa, predominantly in KwaZulu-Natal (KZN), or imported from India. Indian-owned muthi shops sold more species imported from India than alien species that were naturalised and harvested in South Africa. In contrast, the majority of alien species sold at markets and Black-owned shops were harvested in KZN. Viability tests found that 24% of alien plant species sold in this study had greater than 50% viability. Six invasive species are traded in low volumes with viable propagules sold for five of these, highlighting a possibility of spreading through the traditional medicine trade. The study concluded that the total trade in alien plant species is trivial in comparison to the trade of indigenous plant species.
43

Trade in commonly used medicinal bulbs: value and ecological implications

Brueton, Vanessa Jean 25 February 2014 (has links)
The relationship between human activity and the environment has created ecological, socio-economic and cultural patterns and feedback mechanisms that govern the presence, distribution and abundance of plant species assemblages. The trade in traditional medicinal plants in South Africa is estimated to be worth approximately R2.9 billion per year with 27 million consumers throughout the country. Bulbous species compose about 14% of the traded medicinal plant species in South Africa, however the majority of research at the species or generic level has concentrated on a limited number of life forms and plant parts and the ecological consequences of harvest and use of commonly used bulb species is poorly known. Ethnobotanical studies generally focus on ‘ethnospecies’ – i.e. the traditional name that a species may be known by. Species-specific evidence of the effects of trade and harvest is needed to provide more clarity on the implications of trade, especially since increased commercialisation of medicinal plants has often resulted in over-harvesting and, in severe cases, near extinction of valued indigenous plants. The overall aim of this study was to determine the ecological consequences, as well as some of the economic implications of harvesting important bulb species for the regional medicinal plant trade. Traditional medicinal bulb species are susceptible to over-exploitation because they are destructively harvested in large quantities. Four perennial bulbous genera were surveyed: two within the Amaryllidaceae (Boophone and Crinum) and two in the Hyacinthaceae (Bowiea and Drimia). Some discrepancies were noted where traders and traditional healers recognised species that have been synonymised by taxonomists. In order to understand the impacts of all recognised forms, original nomenclature was used to describe different bulb forms that had been synonymised. The proposed ‘functional taxonomy’ does not aim to re-examine the taxonomic revisions by previous taxonomists but rather provides a way to identify forms that have no accepted species name. In this way, the impacts on harvesting of different bulb forms can be quantified. Based on this functional taxonomy, the genus name Urginea has been used although Urginea is currently synonymised under Drimia. However, this is only to describe the different bulb form and is not meant to replace the current taxonomic nomenclature. Surveys were conducted in two national level and two small regional level markets to determine the impacts of trade. Bulb characteristics were described and used together with taxonomic literature to produce a key to bulbous species commonly traded in the markets of South Africa. Distribution data and other important information were collected and combined to provide species-specific information. Identification based on vegetative characteristics was possible, with certain features being more useful than others for creating a key. The most useful identification characteristic was the bulb scale type in the Hyacinthaceae together with bulb shape and colour, while bulb size was least useful. For the Amaryllidaceae, bulb colour and characteristics such as tunics cannot always be used due to similarities between species. However, bulb size and shape are helpful indicators and can group species into classes of similar species. Leaf characteristics are very important and may be the only way to accurately identify some species. The adaptation of taxonomic information and previous keys into more ‘vegetative’ friendly keys can provide ethnoecologists with an identification tool not solely based on ethnospecies name. The ability to identify species will allow ethnoecologists to provide more comprehensive assessments on the impact of the trade. The diameter of bulbs sold at Faraday market (Johannesburg), Warwick market (Durban) and smaller Free State markets were recorded for four genera (Bowiea, Boophone, Crinum, and Drimia – including Urginea forms), and the data were used in a variety of ways to determine the effects of trade. Populations of species of anthropogenic importance should show a corresponding decrease in the frequency of individuals in large size-classes and a decreased number of size-classes with time. Size-class distributions of Drimia delagoensis and Bowiea volubilis followed an inverse J-shaped curve, often indicative of a regenerating population (high frequency of small bulbs); however, in this case intense harvesting pressure has resulted in a highly skewed population structure. High rates of harvesting will ultimately result in regeneration failure because smaller bulbs are unable to reach maturity before harvest. All species studied tended towards smaller mean market bulb diameters over time. These trends suggest that without appropriate mitigation, bulb populations will be further impacted in the future. Bulb diameters in the market were also smaller than diameter records collected from herbarium material and literature records. Bowiea volubilis is the most severely impacted by the medicinal plant trade, with approximately 87% of bulbs <4cm in diameter, and significantly smaller than both bulb diameters in medicinal plant markets in 2001 (p<0.0001) and pressed bulbs from several herbaria (p<0.0001). The large bulbed Amaryllidaceae species Boophone disticha and Crinum species also showed a decrease in bulb diameter between the 2001 and 2007 Faraday surveys (by 1.5cm and 2.7cm, respectively), while Urginea epigea (Hyacinthaceae) showed a 1.2cm decrease in mean size in 6 years. Traditional healers, traders and harvesters can provide a wealth of information on species populations in the wild. Trader and harvester preferences may affect the impact of harvesting and trade on wild populations. Information on trader/harvester preferences and perceptions was gathered from Warwick and Free State markets. Overall, the average earnings per month per trader selling medicinal plants were low (approximately R833 in Warwick and R2,100 in Free State). Bulb species contributed 10-40% of the total earnings per trader at Warwick and 10-50% in the Free State markets. The relatively large contributions of bulb species to trader incomes emphasise the importance of popular bulb species economically and socially. The number of bulbs (equivalent in size to the mean bulb diameter) harvested annually was large and provides an order of magnitude estimate of harvesting impacts on medicinal plant species populations. The number of Drimia elata harvested was greatest in the Free State (between 600,000 and 1,400,000 dependent on estimation method). In Warwick, species sold in the largest quantities were D. robusta, Crinum species, B. volubilis and U. epigea (approximately 400,000 – based on actual volume). The high variability of number of bulbs harvested between traders suggests that these numbers should be treated with caution. The number of populations required and the rate of population regeneration needed to sustain harvesting for the traditional medicine trade is extremely high; and, without mitigating factors, the increased commercialisation of the medicinal plant industry may have potentially dramatic, negative implications on popular bulb populations. Social surveys and ethnobotanical work in local markets are the first steps in understanding patterns of demand for particular plant species, and integrated with population structure and size-class distributions, it allows for an amalgamated and complex awareness of the impacts of resource harvesting. With over 30,000 species of animals and plants that are detrimentally affected by trade worldwide, market surveys are increasingly important to provide information on the extent of trade. The varied data collected in this study included: size-class distributions, temporal changes in bulb diameter, volume and number of bulbs harvested, economic value and trader perceptions. Overall, the results suggested that all species studied were negatively impacted by harvesting to various degrees. In South Africa, harvest and trade is sometimes the only form of income generation and harvest can threaten species populations. By quantifying the volume, value and the number of individuals harvested for bulb species, together with perceived scarcity and popularity and place of harvest, a better understanding of the state of the resource-base has been provided. Continued use of market surveys as monitoring tools is important, because in the current (2011) socio-economic context of South Africa, trade and harvest is likely to increase.
44

A search for biologically active compounds in Acacia (Mimosaceae) species

Wickens, Kristen M. January 2003 (has links)
Indigenous Australians were also known to use plants for medicinal purposes. For thousands of years, Indigenous Australians have used native plants as a source of medicinal agents. Some tribes living in Central Australia still, to this day, prefer to use traditional medicines in favour of the more common and readily available western medicines. A number of plant species endemic to Australia are listed in various Aboriginal pharmacopoeias, with approximately one-third of those species belonging to two genera, Acacia and Eremophila. Of the 1100 recognised species of Acacia, approximately 900 occur in Australia. At least thirty of these species were utilised by the Indigenous Australians as a source of medicine. Extracts of 8 Acacia species were screened using four frontline bioassays. These were the brine shrimp lethality test, the crown gall tumour assays, the disc diffusion antibiotic assay and the seed germination test to determine if any of the species were biologically active. Of all the species screened, Acacia pruinocarpa showed the most promise. The species demonstrated significant activity at concentrations at low as 3.7ppm, which is well below the standard 400ppm exhibited by potassium dichromate (Sam, 1993). Acacia adsurgens and A. dictophleba were the next two promising species exhibiting activity at concentrations of 16.12ppm and 37ppm respectively. This was a trend that was also observed in the Lettuce seed germination test for allelopathy with these three species showing the most promise. Interestingly the potency of A. pruinocarpa extract decreased significantly when it was re- screened after being put through a polyamide column. It can therefore be suggested that as tannins are removed by the polyamide column, the biological activity exhibited by A. pruinocarpa is a result of the tannin content in the species (2%), although more testing is required. / Both A. pruinocarpa and A. adsurgens showed promise as anti-tumour activity when used in the Crown Gall Tumour Assay (CGTA). Acacia pruinocarpa and A. adsurgens both exhibited significant activity when compared to the control producing inhibition percentages of 31% and 37% respectively. Surprisingly, only one of the Acacia species tested inhibited pathogenic growth when tested on the common pathogens Staphylococcus aureus, Streptococcus pyogens and Candida albicans. Acacia bivenosa was the only species to exhibit any activity when tested on the pathogens. This activity, however is not considered to be significant, as the species was only active against one of pathogens tested, Staphylococcus aureus. In order to be considered to be significant, a species must be active against two or more pathogens. It is however, worthy of further evaluation. Acacia species are among the large number of plants that have long been regarded sources of biological activity. This study was guided by the indigenous use of Acacia species as sources of medicine, which led to the use of front-line bioassays. All of the species tested exhibited some form of biological activity. Acacia pruinocarpa demonstrated the most promise as a source of novel biologically active compounds exhibiting activity at very low concentrations. Such compounds have not been determined as it was outside the scope of this study to identify the active constituents of this species. However, it has been suggested that tannins are responsible for eliciting some of the activity observed in A. pruinocarpa. All of the species screened in this study are worthy of further evaluation. The bioassays used in this study are good examples of front-line bioassays. All of the tests used in the study fulfil the criterion, which defines a good test.
45

The Risk of Artemisinin in Early Pregnancy : A Case-Study from Babati District

Rayes, Leila January 2009 (has links)
<p>The intention of the study is to evaluate the risk of artemisinin in early pregnancy through the use of a qualitative research approach, with a focus on rural women in Babati District, Manyara Region, Tanzania.</p><p>Artemisinin-Based Combination Therapy (ACT) is the most effective and recommended antimalarial treatment at the present. Artemisinin compounds are extracted from <em>Artemisia annua</em><em>, </em>a plant which has been used as an herbal medical treatment in China for 2000 years.</p><p>Except few side-effects, there have not been any reports on medical problems due to artemisinin intake during pregnancy. On the other hand, artemisinin tested on animals have revealed that complications such as death of embryos are possible during pregnancy, why more research is needed concerning artemisinin safety in first trimester of pregnancy.</p><p>However, evaluating the risk of artemisinin in pregnancy is referred as complex, when numerous factors could contribute to e.g. fetal loss, abnormalities, or wrong medication. Cultural and economical aspects have to be considered when designing a monitoring system, to enable effective registration of drug quality and drug intake, and follow-up study of mother and child. Accessibility, affordability, possibility and knowledge, are other significant related aspects that have to be managed to eliminate the risk of artemisinin in early pregnancy.</p><p> </p><p><strong></strong></p><p> </p><p> </p>
46

The Risk of Artemisinin in Early Pregnancy : A Case-Study from Babati District

Rayes, Leila January 2009 (has links)
The intention of the study is to evaluate the risk of artemisinin in early pregnancy through the use of a qualitative research approach, with a focus on rural women in Babati District, Manyara Region, Tanzania. Artemisinin-Based Combination Therapy (ACT) is the most effective and recommended antimalarial treatment at the present. Artemisinin compounds are extracted from Artemisia annua, a plant which has been used as an herbal medical treatment in China for 2000 years. Except few side-effects, there have not been any reports on medical problems due to artemisinin intake during pregnancy. On the other hand, artemisinin tested on animals have revealed that complications such as death of embryos are possible during pregnancy, why more research is needed concerning artemisinin safety in first trimester of pregnancy. However, evaluating the risk of artemisinin in pregnancy is referred as complex, when numerous factors could contribute to e.g. fetal loss, abnormalities, or wrong medication. Cultural and economical aspects have to be considered when designing a monitoring system, to enable effective registration of drug quality and drug intake, and follow-up study of mother and child. Accessibility, affordability, possibility and knowledge, are other significant related aspects that have to be managed to eliminate the risk of artemisinin in early pregnancy.
47

The sulphur eaters illness, its ritual, and the social order among the Tagabawa Bagobos of Southcentral Mindanao, Philippines /

Payne, Kenneth William. January 1985 (has links)
Thesis (Ph. D.)--University of Assiut (Egypt), 1985. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (p. 486-506).
48

Devotional music and healing in Badakhshan, Tajikistan preventive and curative practices /

Koen, Benjamin David, January 2003 (has links)
Thesis (Ph. D.)--Ohio State University, 2003. / Title from first page of PDF file. Document formatted into pages; contains xx, 299 p.; also includes graphics (some col.). Includes abstract and vita. Advisor: Margartio Mazo, School of Music. Includes bibliographical references (p. 276-298).
49

Antimicrobial activity of Helichrysum species and the isolation of a new phloroglucinol from Helichrysum caespititium

Mathekga, Abbey Danny Matome. January 2001 (has links)
Thesis (Ph. D.)(Botany)--University of Pretoria, 2001. / Acrobat Adobe Reder needed to open files.
50

The protection of indigenous medicinal knowledge in international intellectual property law /

Lassonde, Marie-Claire January 2003 (has links)
For 20 years, and more intensively during the last decade, indigenous knowledge has challenged the regime of intellectual property. If this field of law has been, in the past, challenged by new technology, it is now, with the problematic of indigenous medicinal knowledge, put to the test by "old invention". The present thesis examines the status of indigenous medicinal knowledge in international intellectual property law. Thus, we will proceed to the study of the main international conventions and the common regime of intellectual property law in order to determine the treatment accorded to medicinal indigenous knowledge within the actual system. The role that intellectual property could play in the future will also be examined.

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