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Pseudoscience : a case study of a South African lifestyle magazine, and a survey of its usageBesaans, Linda Carol 12 1900 (has links)
Thesis (MA)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Across the globe scientists are taking issue with pseudoscience, as well as the role of the media in promoting it. Articles based on pseudoscience, especially those relating to Complementary and Alternative Medicine (CAM) that fall outside the realms of orthodox medicine, are common in all forms of media, but especially in women’s health and lifestyle magazines.
Scientists are quite vociferous in their condemnation of CAM for both ethical and safety reasons, since neither the therapies nor the remedies associated with CAM practices have been proven to be efficacious, or even safe. In fact, some of the therapies and advice offered by CAM practitioners are dangerous and, in some instances, may even be life threatening. Nevertheless, the media continue to promote CAM, and the public continues to support it – despite the warnings and denunciation by scientists.
This is an exploratory study to determine the prevalence of pseudoscience, generally, in South African women’s health and lifestyle magazines, and to uncover the reasons the public supports it. The magazine Longevity is used as an example of this type of publication, and a content analysis is used to illustrate the prevalence of pseudoscience articles and adverts in South African media, while field research, in the form of personal interviews, attempts to determine the reasons people support CAM in spite of its denunciation, as well as the media’s role in fostering this support.
Both mainstream science and pseudoscience are described, while a literature review reveals the scientific perspective of CAM, provides examples of the more popular forms of CAM and the dangers inherent in them, as well as the ways in which science and pseudoscience in general, are handled by the media. Using the hypodermic needle theory, plus the results of the content analysis and field research, this study shows that media promote pseudoscience because it pays; the public support CAM because they believe it works; and that that belief is primarily the result of public disillusionment with the practice of orthodox medicine, rather than the result of media’s promotion of CAM, as scientists contend. / AFRIKKANSE OPSOMMING: Wetenskaplikes van regoor die wêreld het ’n probleem met pseudowetenskap, sowel as die rol wat die media speel om dit bevorder. Artikels gebaseer op pseudowetenskap, veral dié met betrekking tot Aanvullende en Alternatiewe Medisyne (AAM), wat buite die grense van ortodokse medisyne val, is algemeen in alle vorme van media, maar veral in gesondheid-en lewenstyltydskrifte vir vroue.
Wetenskaplikes is baie uitgesproke in hul veroordeling van AAM om beide etiese en veiligheidsredes, omdat nóg die terapie nóg die middels wat verband hou met AAM praktyke bewys is om doeltreffend, of selfs veilig te wees. Trouens, sommige van die terapieë en advies wat aangebied word deur AAM beoefenaars is gevaarlik, en in sommige gevalle selfs lewensgevaarlik. Tog hou die media aan om AAM te bevorder, en die publiek om dit te ondersteun – ten spyte van die waarskuwings en veroordeling deur wetenskaplikes.
Hierdie narvorsing is ’n verkennende studie om die voorkoms van pseudowetenskap in Suid-Afrikaanse vroue se gesondheid- en lewenstyltydskrifte te bepaal, en die redes te ontbloot waarom die publiek dit ondersteun. Die tydskrif Longevity word gebruik as ’n voorbeeld van hierdie tipe publikasie, en ’n inhoudsanalise word gebruik om die voorkoms van pseudowetenskaplike artikels en advertensies in die Suid-Afrikaanse media te illustreer, terwyl navorsing in die veld, in die vorm van persoonlike onderhoude, poog om die redes te bepaal waarom mense AAM ondersteun, ten spyte van veroordeling, sowel as die rol wat die media speel in die bevordering van hierdie ondersteuning. Beide hoofstroom wetenskap en pseudowetenskap word beskryf, terwyl ’n literatuuroorsig die wetenskaplike perspektief van AAM ontbloot, voorbeelde van die meer populêre vorme van AAM word verskaf asook van die gevare daaraan verbonde, sowel as die maniere waarop wetenskap en pseudowetenskap in die algemeen, hanteer word deur die media. Met behulp van die spuitnaald teorie, plus die resultate van die inhoudsanalise en navorsing in die veld, bewys hierdie studie dat die media pseudowetenskap bevorder, want dit betaal; die publiek ondersteun AAM omdat hulle glo dit werk; en dat daardie geloof primêr die gevolg is van openbare ontnugtering met die beoefening van ortodokse medisyne, eerder as die gevolg van die media se bevordering van AAM, soos wetenskaplikes beweer.
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Traditional healing in contemporary South Africa : perspective from traditional health practitioners in Vhembe District (Limpopo).Risimati, Tlharihani Michael 05 1900 (has links)
MAAS / Centre for African Studies / See the attached abstract below
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South African traditional healers' organisations in the context of traditionalism and modernityFenyves, Katalin January 1994 (has links)
A Research Report submitted to the Faculty of Arts, Department of Sociology, University
of the Witwatersrand, Johannesburg, in partial fulfillment for the degree of Master of Arts.
Johannesburg, 1994 / This research report seeks to explore the issues surrounding the organisation of traditiional healers and how their world views can be contextualised within tradtionalism and modernity. [Abbreviated Abstract. Open document to view full version] / MT2017
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An investigation into aspects of medicinal plant use by traditional healers from Blouberg Mountain, Limpopo Province, South AfricaMathibela, Khomotso Malehu January 2013 (has links)
Thesis (M.Sc. (Botany)) -- University of Limpopo, 2013 / Traditional medicine plays a major role in the primary health care of many people
residing in rural areas. People in these areas still consult traditional healers who
utilise plants as medicine. Medicinal plants have come under increasing pressure due to a number of factors, which have resulted in the decline of certain species, extinction in others, and a general decrease in biodiversity of high use areas of South Africa, Blouberg Mountain included. To date there has been a lack of information on how traditional healers utilise the Blouberg Mountain with respect to amounts and species removed, or where the most important collecting sites are located. Thus, no conservation strategy exists for the
Blouberg Mountain to ensure sustainable management of its natural resources.
Furthermore, there is a perception amongst elders of this area that, as with
indigenous knowledge around the world, the knowledge centered around Blouberg’s
medicinal plants is declining, and little formal documentation of that knowledge has
taken place. Consequently, this study investigated aspects related to medicinal plant use such as collection, patterns of collection, legislation, storage and packaging of medicinal plants by traditional healers around Blouberg Mountain. These were documented via a semi-structured questionnaire and a data collection sheet. Furthermore, traditional harvesting methods employed by traditional healers, and in situ conservation issues related to species removal from the mountain were investigated.
Data was collected between September 2010 and September 2011. Sixteen villages in close proximity to the mountain, and 32 healers (two per village) were selected. In
addition 16 consulting rooms were sampled (one per village) in order to gather
information on the number of species collected from the mountain and stored in the
consulting rooms. The 16 most used (indicated by village traditional healers) collection tracks, (one per village surrounding Blouberg Mountain), were travelled with traditional healers to
record botanical and vernacular names of the medicinal plants, vegetation type,
habitat, parts used, harvesting method, replacement value of plant species and
perceived rarity of collected material. A Garmin GPS was used to record waypoints
for the beginning and end of each track. Co-ordinates were logged automatically
every 10 m. A map using Quantum GIS software to capture the position of the healers’ collection tracks, overlaid with topographical and vegetation information, and protected area information of the Blouberg Mountain, was generated. Geographic Information System software was used to geo-process the collection tracks of the healers with respect to where medicinal plants were collected relative to the various vegetation
types. This gave information on vegetation types important to healers. The majority of traditional healers were females. Most of them had no formal education, with only a minority reaching secondary school. Due to their low level of literacy they tended to shy away from sources of written information, with the result
that none of the questioned healers had any knowledge of the various national or
provincial environmental legislations. The majority of them see between 15 and 20
patients per month. Most of the healers had more than 30 years of experience in
traditional healing. The study found 64 plant species commonly used for medicinal purposes. Most of them were harvested for their roots and bark. According to the healers, Boophane disticha and Hypoxis hemerocallidea are declining in Blouberg Mountain, with Warburgia salutaris, endangered in South Africa, not perceived as rare or declining. However, a number of plant species recorded in the Red Data List as of least concern, or not threatened, are seen as rare by the healers. These include Clivia caulescens, Erythrina lysistemon, Lannea schweinfurthii and Maerua juncea.
No exotic species were documented from the surveyed tracks. However, two naturalised exotics were collected from the mountain, namely Cassytha filiformis and Corchorus tridens. Cocculus hirsutus, a naturalised exotic and Abrus precatorius, an exotic species were found in one of the consulting rooms. Dichrostachys cinerea,
Philenoptera violacea and Tarchonanthus camphoratus, which are indicators of bush
encroachment, were identified on selected tracks. Tracks on which indicators of bush
encroachment are present should be investigated more thoroughly to ascertain the
extent and severity of such a threat.
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Investigations into healers’ collection tracks showed that the Soutpansberg Mountain
Bushveld vegetation type is the most heavily utilised of the five vegetation types
around Blouberg Mountain. This vegetation type is vulnerable to human population
densities as most species were collected from it, therefore it should be conserved
and managed if possible as it is targeted for plant species of medicinal value. The
most travelled tracks were found in the Catha-Faurea Wooded Grassland
community.
Solutions to the problems of over harvesting of medicinal plants require local
innovations and the full participation of traditional healers in resource management
initiatives. The development of medicinal plant nurseries together with propagation of
key species will be a crucial management tool, as this will reduce over harvesting of
natural resources from the wild.
In conclusion, it was found that although most species utilised around Blouberg
Mountain are abundant and not threatened, healers are nevertheless concerned
about dwindling medicinal plant supplies. They would welcome conservation
initiatives and the use of GIS maps would be useful in prioritising conservation areas.
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Knowledge, attitude and perception of private practitioners based in Gauteng, South Africa, regarding evidence-based practicede Wet, Wouter 12 1900 (has links)
Thesis (MMed) -- Stellenbosch University, 2010. / Bibliography / Background: Evidence-based medicine (EBM) involves the care of patients using the best available evidence from the results of good quality clinical research to guide clinical decision making 1 – 3. By incorporating the principles of Evidence-based Medicine (EBM), the family practitioner would be able to treat a patient according to the best clinical research available. This principle is implemented widely in the USA, Canada, the United Kingdom and Europe. In South Africa, however, EBM is not yet as widely incorporated into family practice. This is so despite the plethora of websites available to practitioners and the relative ease with which applicable research evidence can be found.
Very few published studies are available regarding EBM or Evidence–based Practice (EBP) in the South African context. The findings of this study would thus highlight reasons and/ or barriers preventing family practitioners from implementing EBM in their respective practices. This could also lead to further research into possible methods of implementation of EBM into South African family practices.
Aim:
The aim of the study was to describe the perceptions, knowledge and attitudes of private practitioners regarding evidence based practice and to identify the barriers encountered in evidence based practice.
Methods
A questionnaire survey of general practitioners in Gauteng, South Africa, was conducted. Questionnaires were distributed to a random sample of practitioners in the Gauteng region. Two hundred and twenty one (221) practitioners participated in the survey and responded to questionnaires mailed to them. The questionnaire was mailed, faxed or e-mailed to the practitioners, which they then completed and returned for statistical analysis.
Study design
The study design is that of quantitative, statistical analysis (descriptive cross-sectional survey).
Setting
General practitioners were randomly selected from a list of practitioners in the Gauteng Province. Doing a nationwide survey would have been a mammoth undertaking. It was therefore decided to limit the research to one province and therefore it was only concentrated on practitioners practicing in the Gauteng area.
Results
It is interesting to note that of the two hundred and twenty one participants in this study; only 10% of the practitioners were against using EBM in their practices. This, however, stands in stark contrast to the 56% of practitioners who do not implement EBM in their practices or make use of the EBM principle at all. The major barriers preventing practitioners from implementing EBM is depicted in the following graph: Lack of time and the training in aspects of Evidence-based medicine were the main barriers preventing the full scale implementation of EBM in family practices in Gauteng.
Conclusion
Participating Gauteng doctors were in principle, very positive towards the implementation of EBM in their respective practices. Most of the participants agreed that EBM would benefit their patients’ care and treatment. Very few of the participants, however, make use of EBM in practice. A lack of training and time constraints were the main barriers with regards to the implementation of EBM. Proper training of medical students at undergraduate level at faculties of health sciences, would go a long way assisting prospective doctors in mastering the concept of EBM and increasing their overall awareness of EBM. Further definitive research would assist in establishing whether such awareness would be associated with improved implementation of evidence in the form of evidence based guidelines in practice.
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Non-divulgence of patients who use traditional medicine in the critical care units of a West Rand Mine HospitalMatlala, Benga Sidwell 03 April 2014 (has links)
M.Cur.(Medical & Surgical Nursing: Critical Care General) / The majority of Africans use traditional medicine, but do not divulge this information to the nurses and doctors when admitted to critical care units. For this reason, patients develop complications, and these makes it difficult for nurses and medical doctors in critical care units to assess and to provide comprehensive quality care, as they treat only the visible clinical manifestations. The purpose of this study was to explore and describe the factors leading to non- divulgence by patients who used traditional medicines in critical care units of a Westrand mine hospital, in order to describe strategies to facilitate divulgence. The researcher used a qualitative, exploratory, descriptive and contextual research design. The population was composed of the patients who were envisaged to have used traditional medicines in the critical care unit of a Westrand mine hospital. Twelve participants were purposively selected from the critical care unit register because these patients displayed the symptoms of having used traditional medicine. Semi-structured individual interviews were conducted. Ethical principles were adhered to. Trustworthiness was ensured by using namely; credibility, transferability, dependability and confirmability. A qualitative open coding method of data analysis was used according to Tesch’s protocol. The following theme and subthemes emerged from the data analysis: Fear and anxiety as the main theme. Subthemes were 1. Fear to divulge secrets. 2. Fear of negative attitudes from nurses and 3. Fear to lose rights, norms and values. It is recommended that the strategies described be used in clinical practice, nursing education and for further research regarding divulgence of the use of traditional medicine to the nurses and doctors, in order to provide a comprehensive assessment and treatment of the patients in critical care units.
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Building a semantic web-based e-health component for a multipurpose communication centreHlungulu, Bulumko January 2010 (has links)
Rural communities have limited access to health information which is made available on the internet. This is due to poor infrastructure (i.e., lack of clinics or Internet access) and that gives them problems in accessing information within the domain of health. The availability of Information and Communication Technologies (ICTs) in a rural community can provide the community with a number of beneficial solutions to their problems as they maximize the potential of knowledge sharing and delivery. This research seeks to make use of ICTs deployed in the community of Dwesa, in order to contribute to improving the health standards of the community. It seeks to accomplish this by carrying out an investigation and literature review with the aim of understanding health knowledge sharing dynamics in the context of marginalized communities. The knowledge acquired will then be used in the development and implementation of a semantic web-based e-Health portal as part of the Siyakhula Living Lab (SLL) project. This portal will share and deliver western medical knowledge, traditional knowledge and indigenous knowledge. This research seeks to make use of a combination of Free and/or Open Sources Software in developing the portal to make it affordable to the community.
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The perception of veterinarians towards chiropractic and the chiropractic treatment of animals in South AfricaTaverner, Charles Bryce January 2011 (has links)
Dissertation submitted in partial compliance with the requirements for the
Master’s Degree in Technology: Chiropractic, Durban University of Technology, 2011. / Introduction: The chiropractic treatment of animals has been integrated into the
veterinary health care systems of various countries outside of South Africa. While South
Africa has seen the integration of the chiropractic treatment of humans into its health
care system, the chiropractic treatment of animals has been slow to develop in this
country. This is evident in the lack of a professional association or education system
concerning the chiropractic treatment of animals in South Africa. Veterinarians
represent the primary contact for animals to receive chiropractic care through referral in
South Africa. It is therefore important to ascertain the knowledge and perception that
veterinarians have towards chiropractic and the chiropractic treatment of animals as
their views and participation could influence the future integration of chiropractic into the
veterinary health care system of South Africa.
Primary Objective: To determine the perception of veterinarians towards chiropractic
and the chiropractic treatment of animals in South Africa.
Methods: A questionnaire was set up on an Internet based website. An electronic mail
(e-mail) was then sent to all the South African veterinarians with a functional e-mail
address registered with the South African Veterinary Council (SAVC), requesting
participation in this research. This amounted to 1841 veterinarians. The veterinarians
who met the inclusion criteria were then able to access and complete the questionnaire
electronically.
Results: A response rate of 13.8% was achieved. The respondents were predominantly
white (87.1%) with an average age of 41.5 years and a nearly even split between male
and female. The veterinary respondents expressed a poor level of confidence relating to
their knowledge of chiropractic and its application to the health care of animals. The
objective knowledge scores for chiropractic and the chiropractic treatment of animals
were 65% and 63%, respectively, giving a reasonably high overall knowledge score of
64%. It was found that the knowledge scores were stronger in the respondents who had
iii
personally utilized a chiropractor as well as being stronger regarding human chiropractic
and overall chiropractic knowledge in those who had referred an animal to a
chiropractor.
The average score for perceptions of the respondents was relatively low (48%), but
positive correlations were found between the knowledge and perceptions of the
respondents regarding chiropractic and \ or the chiropractic treatment of animals.
It was found that the majority of the veterinarian respondents (79.9%) felt that
chiropractors should only be allowed to practice on animals in South Africa under
referral from a veterinarian. The majority of respondents (62.4%) further believed that
the chiropractic treatment of animals should be governed by the South African
Veterinary Council (SAVC) and 57.7 % of the respondents indicated that they would be
in favour of the chiropractic treatment of animals being affiliated to the South African
Veterinary Association (SAVA).
It was determined that 84.4% of the respondents were in support of the formation of a
course concerning the chiropractic treatment of animals in South Africa, with 49.1%
further stating they would be interested in attending such a course. The majority of
respondents indicated that they believed both veterinarians and chiropractors should
administer (77.2%) and be able to attend (75.1%) such a course.
Conclusion: This study has established a knowledge base that will facilitate greater
understanding of the perceptions that South African veterinarians have towards
chiropractic and the chiropractic treatment of animals as well as the part they perceive
chiropractic to play in the South African veterinary health care system. The various
outcomes should be noted when considering the future education of South African
veterinarians regarding chiropractic, as well as the development of the chiropractic
treatment of animals in South Africa.
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Die maatskaplike werker as ondersteuningsbron vir geneeshere in privaat praktykVogt, Tertia 12 1900 (has links)
Thesis (MSocialWork)--Stellenbosch University, 2001. / ENGLISH ABSTRACT: The aim of this study was to compile practical guidelines to assist medical practitioners in
utilizing social work services in their practices. Exploratory, descriptive and applied
research was done to determine and describe medical practitioners' knowledge of
psychosocial problems and their present and potential utilization of social work services.
Results were generalized in respect of the population as a whole.
In the theoretical study social functioning was conceptualized by the description of
micro, mezzo and macro levels of functioning. The approach towards rendering of
services (in the Medical field) and intervention (in the Social Work field) was described,
followed by recommendations for the eclectical utilization of the approaches.
The eclectical application of the intervention approaches requires that social workers
should have certain knowledge, values and skills to interpret certain roles. This occurs
within certain social work areas, with the achievement of the aims and functions of Social
Work as goal. The ethical and value basis of Social Work and Medical Science shows
certain similarities and disparities. The values of Social Work, as contained in the
Behavioural- and Ethical Code for Social Work and the Oath of Hippocrates, in Medical
Science, are described in this study.
In the empirical study qualitative and quantitative information was gathered, inter alia,
about the existence of psychosocial problems of patients in medical practitioners'
practices, how medical practitioners handled them, how well equipped they were to do it,
their present and potential utilization of Social Work services, the role of third parties in
the rendering of services and referral procedures. Thirty nine (39) medical practitioners,
selected by random sampling procedure, were involved in the study and completed selfadministered
questionnaires.
The majority respondents indicated that their undergraduate training was inadequate in
enabling them to handle psychosocial problems of patients. The entire spectrum of
psychosocial problems existed in all the respondents' practices. The majority of
respondents handled such problems themselves, while specialists, psychologists and
psychiatrists were at times used as resources. The majority of respondents indicated that
they could perhaps utilize Social Work services and that there is a great need for such a
resource. Most medical practitioners preferred to send written referrals via patients, with
the responsibility being with the patient for making an appointment with the social
worker. Minimal use was made of third parties in the patients' frame of reference in the
assessment and treatment of patients.
Third parties, within the reference framework of patients, were used minimally by
medical practitioners in the making of assessments and the rendering of services.
Respondents had divergent opinions regarding their competence in the psychosocial field
of service rendering. The majority of respondents indicated the need for training
programs focusing on the handling of patients' psychosocial problems. Limited time for
attending such training programs was however mentioned as the biggest obstacle. These
findings of the empirical study, together with the theoretical framework, were used as a
guideline for the composition of a practical guideline for the referral of services to social
workers in private practice. / AFRIKAANSE OPSOMMING: Die doelstelling van hierdie studie was om praktykriglynne te ontwikkel, waarvolgens
geneeshere in privaat praktyk maatskaplike werkers as ondersteuningshulpbron kan
benut. Verkennende, beskrywende en toegepaste navorsing is gedoen, ten einde
geneeshere se kennis van psigososiale probleme en hul huidige en potensiele benutting
van maatskaplikewerkdienste te bepaal en te beskryf. Bevindinge is ten opsigte van die
populasie as geheel veralgemeen.
In die teoretiese studie is maatskaplike funksionering deur die beskrywing van mikro-,
meso- en makrovlakfunksionering, gekonseptualiseer. Die benaderings tot dienslewering
(in Geneeskunde) en intervensie (in Maatskaplike Werk) is beskryf. Daarna is 'n
aanbeveling vir die eklektiese benutting van die benaderings gedoen.
Die eklektiese benutting van die intervensiebenaderings vereis dat maatskaplike werkers
oor sekere kennis, waardes en vaardighede moet beskik en sekere rolle moet vertolk. Dit
geskied binne sekere maatskaplikewerkvelde en het as mikpunt die verwesenliking van
die doelstellings en funksies van Maatskaplike Werk. Die etiese en waardegrondslag van
Maatskaplike Werk en Geneeskunde toon sekere ooreenkomste en verskille. Die waardes
van Maatskaplike Werk, soos vervat in die Gedrags- en Etiese Kodes vir Maatskaplike
Werk, en van Geneeskunde, soos vervat in die Eed van Hippocrates, word in hierdie
studie bespreek.
In die empiriese studie is kwalitatiewe en kwantitatiewe inligting ingesamel oor, onder
andere, die voorkoms van psigososiale probleme by pasiente in geneeshere se praktyke,
geneeshere se hantering daarvan, hul bekwaamheid om sodanige probleme te hanteer,
hul huidige en potensiele benutting van maatskaplikewerkdienste, die rol van derde
partye by dienslewering en verwysingsprosedures. Nege-en-dertig (39) geneeshere,
geselekteer deur ewekansige steekproeftrekking, is by die ondersoek betrek en het self
die vraelyste ingevul.
Die meeste geneeshere het aangedui dat hul voorgraadse opleiding hulle nie voldoende
toegerus het om psigososiale probleme by pasiente te hanteer nie. Die hele spektrum van
psigososiale probleme het in respondente se praktyke voorgekom. Die meeste
respondente het sodanige probleme self hanteer, terwyl spesialiste, sielkundiges en
psigiaters soms as hulpbronne benut is. Die meeste respondente het aangetoon dat hulle
moontlik van maatskaplike werkers gebruik kan maak en dat daar 'n groot behoefte aan
sodanige hulpbron bestaan. Die verwysingsprosedure wat deur die meeste geneeshere
verkies is, was die stuur van skriftelike verwysings saam met pasiente.
Derde partye, in pasiente se verwysingsraamwerk, is minimaal deur geneeshere by
assessering en dienslewering betrek. Geneeshere het uiteenlopende menings gehad oor
hul bevoegdhede in die psigososiale veld van dienslewering. Die behoefte aan
opleidingsprogramme, wat fokus op die hantering van psigososiale probleme by pasiente,
is deur die meeste respondente aangedui. Beperkte tyd is egter as die grootste struikelblok
vir die bywoning van sodanige opleidingsessies aangevoer. Hierdie bevindinge van die
empiriese studie, saam met die teoretiese raamwerk, is as riglyn benut vir die
ontwikkeling van 'n praktykriglyn vir verwysing van dienste na maatskaplike werkers in
privaat praktyk.
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Isolation and characterisation of secondary metabolites of two asteraceae species, Artemisia afra and Elytropappus rhinocerotis.Gakuba, Emmanuel. January 2009 (has links)
In this study two medicinal plant species, namely Artemisia afra Jacq. ex. Willd and Elytropappus rhinocerotis Less. (L.f) (= Dicerotamnus rhinocerotis Koekemoer), both belonging to the family Asteraceae, have been investigated and different compounds isolated and characterised. Both species are important plants used in traditional medicine in general in Africa and particularly in South Africa. A. afra, commonly called "African wormwood" is one of 400 species belonging to the genus Artemisia and it is the only one indigenous to Africa. E. rhinocerotis is one of eight Elytropappus species which are all restricted to the Cape floristic region. The aim of this study was to investigate the phytochemistry of these species. In total fifteen compounds were isolated and characterised. From the E. rhinocerotis extract, four known compounds, labdanolic acid, methyl labdanolate, 6, 7- dimethoxycoumarin and a sesquiterpene viridiflorol were isolated. These compounds were not previously reported from E. rhinocerotis. Two different chemotypes of A. afra were studied and eleven compounds were isolated. These compounds include sesquiterpenes such as taurin, artesin, maritimin, artemin, norsantolinifolide, santolinifolide A, and reynosin, a flavonoid, 5- hydroxy-7,4-dimethoxyflavone, a coumarin called scopoletin or 7-hydroxy-6- methoxycoumarin and other aromatic compounds such as p-hydroxyacetophenone, and 2,4-dihydroxy-6-methoxyacetophenone. Except for taurin, scopoletin and 5-hydroxy-7, 4- dimethoxyflavone , none of these other compounds has been reported previously from A. afra. This study has shown that A. afra contains a large number of sesquiterpenoids, mostly from the eudesmane-type. Structural elucidation of different compounds was performed using mainly NMR spectroscopy. Other methods used for identification include LC-MS and infrared spectroscopy. The major compound, labdanolic acid, is known to selectively inhibit cyclooxygenase-2, an enzyme associated with inflammation. The presence of labdanolic acid in the plant may account for its traditional use as an anti-inflammatory. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2009.
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