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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.

Prevalence of Escherichia coli O157:H7 among diarrhoeic HIV/AIDS patients in the Eastern Cape Province - South Africa

Abong'o, BO, Momba, MNB, Malakate, VK, Mwambakana, JN 25 April 2008 (has links)
This study investigated the prevalence of Escherichia coli O157:H7 in the stool of confirmed and non-confirmed diarrhoeic HIV/AIDS patients. Escherichia coli O157:H7 was isolated by culture-based and immunomagnetic separation from three hundred and sixty stool swabs. Identification was by conventional IMViC, 20E API and molecular techniques. Confirmed and non-confirmed diarrhoeic HIV/AIDS patients had 56.5% (74/131) and 43.5% (57/131) respectively of E. coli O157:H7. Molecular results indicated that the prevalence of E. coli O157:H7 was 12.16% (9/74) and 8.77% (5/57) from stool swabs of confirmed and non-confirmed diarrhoeic HIV/AIDS patients. Antimicrobial resistance was higher for E. coli O157:H7 isolates from stools of confirmed HIV/AIDS than it was for non-confirmed HIV/AIDS patients. Escherichia coli O157:H7 might be a silent cause of diarrhoea in HIV/AIDS patients. It is recommended that HIV/AIDS patients with diarrhoea should be screened for E. coli O157:H7 and surveillance programmes for these bacteria should be established in both urban and rural areas of South Africa.

Factors contributing to the presence of Escherichia coli O157:H7 and O157:NM in feedlots and feedlot cattle.

Ungkuraphinunt, Paphapit 15 November 2004 (has links)
Environmental sources within 5 feedlots were sampled for E. coli O157:H7 and O157:NM to determine the prevalence of this pathogen with a view to minimize or control its spread in the feedlot environment. Monthly samples were taken from the feedlots in the Panhandle and South Plains of Texas over a nine-month period. Samples were examined by an immunomagnetic bead separation, followed by plating onto CT-SMAC and CHROMagar O157 media. Sorbitol-negative colonies were tested using ImmunoCard Stat! E. coli O157:H7 Plus and confirmed as E. coli O157:H7, using biochemical (Vitek system) and serological tests (latex agglutination). Additionally, one hundred sponge samples were collected from the hides of stunned cattle at the slaughter plant. All isolates were subjected to rep-PCR DNA fingerprinting and antimicrobial profiling. E. coli O157 was isolated from hide (56%) and environmental samples (4%). E. coli O157 was isolated from all environmental sources, with peak prevalence during November (9%) and March (10%). At least one sample from each feedlot was positive 42% of the time. The most contaminated sites were the chute area (6%) and sludge from waste water ponds (6%). Positive samples were most frequently found from feedlot 5 (7%) and the greatest variation in positive samples between feedlots (0-34%) occurred during March. A decrease in the presence of E. coli O157 in feedlots was observed during January (0%), when ambient, water, and pond sludge temperatures were consistently low. No correlation with other environmental factors was observed. Hide was a primary source of E. coli O157 on carcasses with an overall prevalence of 56%. Of two sampling days, the number of positive hide samples varied from 14% for the first day to 98% for the second day. The total positive samples collected (environmental (47); hide (56)) were 64% H7, and 36% NM. The environmental isolates showed similar antibiotic resistance patterns, regardless of the source. Most E. coli O157 isolates from the feedlots and hides showed a high level of resistance to cephalothin (45%) and sulfisoxazole (56%). E. coli O157 isolates from feedlots were resistant to more than 10 antibiotics (9/317). All of the isolates appeared highly similar, with an average similarity of 53% by rep-PCR DNA fingerprinting.


Hajira, Noorein 25 April 2012 (has links)
Dental caries is a widespread global public health problem with significant health and financial implications. The purpose of this study was to determine dental caries prevalence, experience and severity, as well as to investigate disparities by geographic (urban/rural) location, dental health care utilization and oral hygiene practices in seven to eight year old Nova Scotia school children in 2006-2007. The study results demonstrated that over half (57.3%) of the seven to eight year old population was afflicted by dental caries in the overall dentition. Primary dentition caries prevalence was 55%, with a mean deft score of 2.58 ± 0.08 SE. Prevalence of permanent dentition caries was 14%, with a mean DMFT score of 0.26 ± 0.02 SE. The mean defs score was 6.86 ± 0.28 SE and the average DMFS score was 0.47 ± 0.04 SE. Geographic location was not found to have a major influence on dental caries prevalence, experience and severity in this population. However, a significant relationship was observed between dental caries and dental visit frequency, with higher overall caries prevalence and severity among those who visited the dentist less than once per year. Disparities in dental caries were also found by frequency of brushing, with significantly lower caries rates in those who brushed at least twice per day. Health promotion measures such as pit and fissure sealants and topical fluoride application in susceptible and high-risk children, and appropriate health education regarding recommended frequency of brushing twice per day using fluoridated toothpaste, as well as preventive and regular dental visits are merited to help promote children’s overall health and well-being.

A study of the aetiology of wheezing illness and allergic disease in children using data from the 1958 and 1970 British birth cohorts

Lewis, Sarah January 1997 (has links)
No description available.

Population-based prevalence of malaria among pregnant women in Enugu State, Nigeria: the Healthy Beginning Initiative

Gunn, Jayleen KL, Ehiri, John E., Jacobs, Elizabeth T., Ernst, Kacey C., Pettygrove, Sydney, Kohler, Lindsay N., Haenchen, Steven D., Obiefune, Michael C., Ezeanolue, Chinenye O., Ogidi, Amaka G., Ezeanolue, Echezona E. January 2015 (has links)
BACKGROUND: Malaria adversely affects pregnant women and their fetuses or neonates. Estimates of the malaria burden in pregnant women based on health facilities often do not present a true picture of the problem due to the low proportion of women delivering at these facilities in malaria-endemic regions. METHODS: Data for this study were obtained from the Healthy Beginning Initiative using community-based sampling. Self-identified pregnant women between the ages of 17-45 years were recruited from churches in Enugu State, Nigeria. Malaria parasitaemia was classified as high and low based on the malaria plus system. RESULTS: Of the 2069 pregnant women for whom malaria parasitaemia levels were recorded, over 99 % tested positive for malaria parasitaemia, 62 % showed low parasitaemia and 38 % high parasitaemia. After controlling for confounding variables, odds for high parasitaemia were lower among those who had more people in the household (for every one person increase in a household, OR = 0.94, 95 % CI 0.89-0.99). CONCLUSION: Results of this study are consistent with hospital-based estimates of malaria during pregnancy in southeastern Nigeria. Based on the high prevalence of malaria parasitaemia in this sample, education on best practices to prevent malaria during pregnancy, and resources in support of these practices are urgently needed.

Endoparazitózy jelena siky (Cervus nippon) v Západních Čechách

Martin, Tomáš January 2008 (has links)
No description available.

Prevalence of enterohaemorrhagic Escherichia coli O157:H7 in drinking water and its predicted impact on diarrhoeic HIV/AIDS patients in the Amathole District, Eastern Cape Province, South Africa

Momba, MNB, Abong'o, BO, Mwambakana, JN 03 July 2008 (has links)
Immunosuppressed persons such as HIV/AIDS patients are at risk of acquiring diarrhoeal infections from water-borne E. coli O157:H7. In the present study, we investigated the prevalence of E. coli O157:H7 in drinking water collected from selected distribution systems within the Amathole District of the Eastern Cape and its predicted impact on diarrhoeic conditions of HIV/AIDS persons living in this area. One hundred and eighty water samples and 360 stool swabs from confirmed and nonconfirmed HIV/AIDS diarrhoeic patients were analysed. Escherichia coli O157:H7 were isolated using enrichment culture and confirmed using molecular techniques. Of the 180 drinking water samples, 46 (25.56%) were positive for E. coli O157. The prevalence of E. coli O157 in the stools was at 36.39% (131/360) of which 56.5% (74/131) and 43.5% (57/131) were from stools of confirmed and non-confirmed HIV/AIDS patients, respectively. Molecular analysis of 27, 25 and 29 representative presumptive E. coli O157 from water and stools of confirmed and non-confirmed HIV/AIDS patients, respectively, revealed that 14.81%, 36% and 17.24% of the isolates were E. coli O157:H7. The findings predicted a possible link between E. coli O157:H7 isolated from drinking water and diarrhoeic conditions of both confirmed and non-confirmed HIV/AIDS patients visiting Frere Hospital for treatment.

The knowledge, attitudes,practices and prevalence of alcohol and cannabis use amongst South African diamond miners

Onwukwe, Victor Nnanna 17 November 2006 (has links)
Faculty of Health Sciences School of Public Health 0003100h Vicon@tiscali.co.za / The causative association between alcohol, cannabis use and accidents in the workplace have been shown in some studies. The adverse effects of these on employee’s health, work performance, public and industrial safety have also been researched internationally. But there still remains a paucity of information on the knowledge, attitudes, practices and prevalence of alcohol and cannabis use on diamond mines in South Africa even though anecdotal evidence suggests widespread use that is on the rise. As a result of this, effective intervention strategies to stem the rise have not been developed. This study assessed the knowledge, attitudes, practices and prevalence of alcohol and cannabis use amongst South African diamond miners. It was a cross-sectional analytical study which ascertained the knowledge, attitudes and practices of the miners in relation to alcohol and cannabis use through face to face structured interviews. The prevalence of alcohol was ascertained through breathalyser testing and that of cannabis through urine tests. The study site was a large diamond mine located in the northern part of South Africa. Individual written informed consent was obtained from each of the participants before questionnaire interviews, breathalyser and urine tests were carried out. All the interviews and tests were anonymous and unlinked. None of the test methods were invasive. The questionnaire was tested in a pilot survey. This research was commissioned by the Safety in Mines Research and Advisory Committee (SIMRAC). vii The reported prevalence for alcohol was 44% whilst the tested prevalence was 1.4%.For cannabis, the reported prevalence was 2.0% whilst the tested prevalence was 2.8%.The significant factors associated with alcohol use were higher educational qualification and type of work. Full time employees were more likely to have ever used alcohol. Reported users of alcohol and cannabis started before starting work on the mines. An overwhelming majority of the participants reported that alcohol and cannabis use could lead to accidents on the mines. A large majority reported that intervention strategies such as education, regular testing of employees and entertainment will decrease the use of alcohol and cannabis. Possible explanations for the patterns observed in the use of these substances have been given and suggestions on how to influence the use of these substances have been made.

Epidemiology and Genetics of Pituitary Tumors Épidémiologie et génétique des adénomes hypophysaires

Daly, Adrian Francis 18 January 2008 (has links)
Pour avoir une parfaite compréhension dune maladie, il est nécessaire den connaitre la fréquence, la symptomatologie et les causes dapparition. Dans le cas des adénomes hypophysaires, les données de la littérature concernant lépidémiologie de ces tumeurs sont contradictoires certaines études suggérant une haute prévalence, et dautres affirmant quelles sont plutôt rares. En parallèle, la compréhension de la physiopathologie des tumeurs endocrines telles que les adénomes hypophysaires a fait un bond en avant avec lavènement des techniques de biologie moléculaire. Pourtant, leur physiopathologie reste encore très floue. Le fait de se concentrer sur les causes familiales permet dapprocher plus efficacement les causes des tumeurs endocrines. Concernant les adénomes hypophysaires, mis à part les Néoplasies endocriniennes multiples de type I (MEN1) et le Complexe de Carney (CNC), le domaine des adénomes hypophysaires familiaux est peu compris. En effet, mise à part lacromégalie familiale, il ny a eu aucune étude sur dautres types dadénomes hypophysaires entrant dans le cadre familial. Les buts du travail contenu dans cette thèse étaient de décrire des aspects épidémiologiques et génétiques des adénomes hypophysaires. Tout dabord, nous avons étudié la discordance entre les taux de prévalence dadénomes hypophysaires provenant détudes radiologiques/autopsiques (les incidentalomes étant très fréquents) et dautre part ceux provenant de registres de cancers et plus rarement de données de population. Une étude intensive et complète de la prévalence des adénomes hypophysaires a été réalisée dans 3 régions géographiquement parfaitement délimitées dans la province de Liège. Dans cette étude qui a concerné une population de plus de 70 000 habitants, les adénomes hypophysaires diagnostiqués lont été en collaboration avec toute la communauté médicale de ces régions. Les données démographiques, cliniques, hormonales, radiologiques et pathologiques de tous les patients ont été confirmées de façon indépendante. A une date fixe, nous avons montré que les adénomes hypophysaires diagnostiqués suite à des symptômes cliniques surviennent avec une prévalence de 1 cas par 1064 habitants résidants dans les limites géographiques déterminées pour cette étude. Ces résultats montrent que la prévalence des adénomes hypophysaires évidents sur le plan clinique est de 3.5 à 5 fois plus haute que les estimations précédentes se rapportant à des populations ou des registres. Cela suggère que les adénomes hypophysaires significatifs sur le plan clinique surviennent assez fréquemment dans la pratique de tous les jours et ceci peut avoir des implications importantes sur la distribution des ressources de santé. Une étude épidémiologique internationale appliquant la même méthodologie est actuellement en cours. Létude des adénomes hypophysaires familiaux en-dehors du contexte de la polyendocrinopathie de type I ou du Complexe de Carney constitue la deuxième partie de ce travail. Jusquà présent, seule lacromégalie familiale avait été rapportée dans la littérature. Nous avons réalisé une étude internationale pour démontrer que tous les types dadénomes hypophysaires pouvaient survenir dans le cadre dune pathologie familiale différente de la polyendocrinopathie de type I et du complexe de Carney. La suspicion de cette pathologie est née à Liège au cours de la dernière décennie. Cette étude a démontré que les adénomes hypophysaires familiaux isolés (Familial Isolated Pituitary Adenoma ou FIPA) constituent 2% des adénomes hypophysaires et 64 familles FIPA ont été caractérisées cliniquement. Cette étude a démontré pour la première fois que tous les phénotypes dadénomes hypophysaires peuvent survenir dans les mêmes familles. Quelques familles montrent seulement un phénotype parmi les membres atteints (familles FIPA homogènes) et dautres familles montrent différents types de tumeurs chez les patients atteints (famille FIPA hétérogène). Dans les familles FIPA, les adénomes hypophysaires étaient plus agressifs et tendaient à survenir à un âge plus jeune que dans les cas sporadiques. Les familles FIPA montrent une grande proximité familiale entre les membres atteints suggérant un mode dominant de transmission. Les études ultérieures ont été réalisées sur les aspects génétiques et anatomo-pathologiques des adénomes hypophysaires et particulièrement ceux qui survenaient dans le contexte FIPA. La découverte dun gène nouveau aryl hydrocarbon receptor interacting protein (AIP), dont quelques mutations ont été associées avec des adénomes hypophysaires nous a conduit à entreprendre la première étude génétique dans les FIPA. Des mutations AIP ont été découvertes dans 15 % des familles et 50% des familles homogènes dacromégales dans le contexte FIPA. Ceci suggère que dautres gènes peuvent également être responsables du contexte FIPA. Dans les familles FIPA qui portent la mutation AIP, les tumeurs étaient plus importantes et survenaient à un âge plus jeune que dans les familles FIPA sans mutation AIP. Neuf nouvelles mutations AIP ont été identifiées, dont la majorité permet de prédire la perte du ligand ou de la région de AIP qui interagit avec son récepteur. Une mutation AIP dans les FIPA était associée avec différents types dadénomes hypophysaires incluant acromégalie, prolactinomes, adénomes mixtes à GH-prolactine et adénomes nonsécrétants. Nous avons également observé que la même mutation AIP pouvait être responsable de différents phénotypes dans 2 familles FIPA différentes. Un suivi détaillé dune famille FIPA avec mutation AIP a permis de montrer pour la première fois quune anomalie endocrinienne différente dune tumeur hypophysaire pouvait survenir chez des porteurs de mutation AIP (élévation de lIGF1). Une analyse détaillée de lADN germinal et somatique provenant dun grand groupe international européen dadénomes hypophysaires sporadiques (non familiaux) a montré que les mutations AIP surviennent rarement dans cette condition. En conclusion : Le travail entrepris a apporté une nouvelle compréhension de la vraie prévalence des adénomes hypophysaires diagnostiqués de façon clinique dans une population et il a permis de codifier et de caractériser le désordre FIPA, une nouvelle entité clinique qui représente une aire de recherche potentielle pour des études cliniques et génétiques impliquant la fonction de AIP et dautres gènes non encore identifiés. To have a full understanding of a disease, it is necessary to at least know how frequently it occurs, its clinical features and by what means it is caused. In the case of pituitary adenomas, data in the literature on the epidemiology of these tumors is conflicting, with some studies suggesting a high frequency, others that they occur rarely in the clinical setting. In parallel, the understanding of the pathophysiology of endocrine tumors like pituitary adenomas has advanced greatly with the advent of molecular genetic techniques. However, much remains unclear regarding pathophysiology. A valuable avenue for studying the causes of endocrine tumors has been to focus on the familial setting. With respect to pituitary adenomas, apart from multiple endocrine neoplasia type 1 (MEN1) and Carney complex (CNC), the field of familial pituitary tumors is poorly understood. Indeed, apart from familial acromegaly, there have been virtually no studies on other pituitary adenomas occurring in the familial setting. The aims of the work described in this thesis were based on addressing aspects of the epidemiology and genetics of pituitary tumors. Firstly, the disconnect between the prevalence rates for pituitary adenomas from autopsy/radiology studies (incidentalomas being very common) and cancer registries/population data (rare) was studied. An intensive, comprehensive, case-finding study of the prevalence of pituitary adenomas was performed in three tightly-defined geographical areas in the Province of Liège. In this study, which involved a population of more than 70,000 people, diagnosed pituitary adenomas were sought in collaboration with the entire group of community medical practitioners in the study areas, and the demographics and clinical, hormonal, radiological and pathological features of all patients were confirmed independently. On a fixed date, it was found that clinically diagnosed pituitary adenomas occurred with a prevalence of 1 case per 1064 individuals residing within the geographic boundaries of the study. These results report a clinical prevalence of pituitary adenomas that is 3.5 to 5 times higher than previous population/registry estimates. It suggests that clinically relevant pituitary adenomas occur frequently in the everyday clinical setting, which may have important implications for health resource allocations. Also, it is possible to undertake detailed, comprehensive, crosssectional epidemiological studies in well-defined geographic areas, and this methodology can be applied internationally Studying the familial occurrence of pituitary adenomas outside of MEN1 and CNC was the next aim of the work described. Up to this time, only the familial occurrence of acromegaly had been reported with any frequency in the literature. An international study was undertaken to assess whether isolated pituitary adenomas of all types could occur in the familial setting, a suspicion raised in Liège over the past decade. This study demonstrated that familial isolated pituitary adenomas (FIPA) occur in about 2% of pituitary adenoma populations, and 64 FIPA families were characterized clinically. The study demonstrated for the first time that all phenotypes of pituitary adenomas can occur together in families; some families exhibit only one phenotype among affected members (homogeneous FIPA kindreds), others have multiple tumor types among affected family members (heterogeneous FIPA). In FIPA families, pituitary tumors were more aggressive and tended to occur at a younger age than sporadic pituitary adenomas. FIPA families display a high degree of familiality, suggesting a dominant mode of inheritance. Subsequent studies were performed on the genetic and pathological features of pituitary adenomas, particularly those occurring as FIPA. The discovery of a novel gene, aryl hydrocarbon receptor interacting protein ( AIP), mutations in which were associated with isolated pituitary adenomas, led us to undertake the first such genetic studies in FIPA. AIP mutations account for a minority (15%) of FIPA families and 50% of familial acromegaly kindreds in FIPA. This suggests that other genetic causes for FIPA also exist. In AIP mutation carrying FIPA families, tumors were larger and had a younger age at diagnosis than non- AIP mutated FIPA kindreds. A series of 9 novel AIP mutations were identified, the majority of which led to predicted loss of vital ligand and receptor interacting regions of the AIP protein. AIP mutations in FIPA were associated with multiple pituitary adenoma types, including acromegaly, prolactinomas, mixed growth hormone/prolactin secreting adenomas and non-secreting tumors. It was also found that the same AIP mutation was responsible for different pituitary adenoma types in two separate FIPA families. A detailed follow-up study of an individual FIPA kindred with an AIP mutation found for the first time that non-pituitary tumor-associated endocrine abnormalities (elevated circulating insulin-like growth factor-1) occur in AIP mutation carriers. A detailed analysis of germline and somatic DNA from a large international European cohort of sporadic (non-familial) pituitary adenoma cases showed that AIP mutations occur rarely in this setting. In conclusion, the work undertaken has provided new understanding of the true prevalence of clinically-relevant pituitary adenomas in the population, in addition to codifying and characterizing FIPA, a new clinical entity that represents a potentially valuable area for genetic and clinical studies involving the function of AIP and other as yet unidentified associated genetic causes.

Zabraňují či pomáhají kondomy šíření AIDS? / Do condoms prevent or help the spread of HIV virus?

Jánská, Zuzana January 2009 (has links)
The male condoms were massively expanded to Africa in 1990s as a result of growing HIV prevalence in most parts of Sub-Saharan Africa. Many transnational non-profit organizations together with national governments were engaged in this expansion of condom distribution. The biggest condom donator are the United States of America which have already provided tens of milliards of dollars to fight against AIDS by distribution of condoms. Was this financial aid used effectively and did the money have the right intended effect? Scientists agree on the statement that the effectiveness of condoms as contraceptives is around 90%. What is the efficiency of using condoms helping against the transmission of the virus HIV, if a single HIV virus cell is much smaller than a sperm cell? With the help of regression analysis using panel data we can give a definite answer to the crucial question -- do condoms help or prevent the spread of HIV virus?

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