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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.
1

The establishment of normal adult reference values for a selected panel of laboratory analytes in South Africa

Smit, Francois Christiaan January 2019 (has links)
Thesis (PhD (Biomedical Sciences))--Cape Peninsula University of Technology, 2019
2

Nutrient intake of WIC participants ages 6-28 months compared to dietary reference intakes

Turner, Kara L. January 1900 (has links)
Thesis (M.S.)--West Virginia University, 2004. / Title from document title page. Document formatted into pages; contains vi, 67 p. : map. Includes abstract. Includes bibliographical references (p. 44-45).
3

Lung function and prevalence trends in asthma and COPD : the Obstructive Lung Disease in Northern Sweden Thesis XVI

Backman, Helena January 2016 (has links)
Background Asthma and chronic obstructive pulmonary disease (COPD) are common obstructive airway diseases with a substantial burden in terms of morbidity, mortality and costs. Smoking is the single most important risk factor for COPD, and is associated with incident asthma. It is important to know if the prevalence of asthma and COPD is increasing or decreasing in the population in order to effectively allocate health care resources. The definitions of these diseases have varied over time which makes it difficult to measure changes in prevalence. The preferred method is to estimate the prevalence with the same procedures and definitions based on cross-sectional population samples with identical age distributions in the same geographical area at different time points. Measurements of lung function (spirometry) are required to diagnose COPD, and spirometry is used to evaluate disease severity and progress of both asthma and COPD, where observed values are compared to reference values. The most commonly used reference values in Sweden are published during the mid 1980s, and there are few evaluations of how appropriate they are today based on Swedish population samples. The aim of the thesis was to estimate trends in the prevalence of asthma and COPD in relation to smoking habits, and to evaluate and estimate reference values for spirometry. Methods The project was based on population-based samples of adults from the Obstructive Lung Disease in Northern Sweden (OLIN) studies. Postal questionnaires were sent to large cohorts, recruited in 1992 (n=4851, 20-69 years), 1996 (n=7420, 20-74 years) and 2006 (n=6165, 20-69 years), respectively. The questionnaire included questions on respiratory symptoms and diseases, their comorbidities and several possible risk factors including smoking habits. Structured interviews and spirometry were performed in random samples of the responders to the 1992 and 2006 surveys, of which n=660 (in 1994) and n=623 (in 2009) were within identical age-spans (23-72 years). The trend in asthma prevalence was estimated by comparing the postal questionnaire surveys in 1996 and 2006, and the trend in COPD prevalence was estimated by comparing the samples participating in dynamic spirometry in 1994 and 2009, respectively. The prevalence of COPD was estimated based on two different definitions of COPD. Commonly used reference values for spirometry were evaluated based on randomly sampled healthy non-smokers defined in clinical examinations of participants in the 2006 postal questionnaire (n=501). The main focus of the evaluation was the global lung function initiative (GLI) reference values published in 2012, for which Z-scores and percent of predicted values were analysed. New sex-specific reference values for spirometry were estimated by linear regression, with age and height as predictors. These new OLIN reference values were also evaluated on a sample of healthy non-smokers identified in the population-based West Sweden Asthma Study. Results Although the prevalence of smoking decreased from 27.4% to 19.1%, p<0.001, between 1996 and 2006, the prevalence of physician-diagnosed asthma increased from 9.4% to 11.6%, p<0.001. The prevalence of symptoms common in asthma such as recurrent wheeze did not change significantly between the surveys or tended to decrease, while bronchitis symptoms such as cough and sputum production decreased significantly. The evaluation of the GLI reference values showed that the predicted values were significantly lower compared to the observed values in Norrbotten, which makes the percent of predicted too high. This was especially true for FVC percent predicted with a mean of 106%. In general, the deviations were more pronounced among women. New OLIN reference values valid for the Norrbotten sample were modelled and showed a high external validity when applied on the sample from western Sweden. The prevalence of moderate to severe COPD decreased substantially over the 15-year period between 1994 and 2009, regardless of definition. Conclusions In parallel with substantially decreased smoking habits in the population between 1996 and 2006, the prevalence of several airway symptoms decreased while the prevalence of physician-diagnosed asthma increased. These results suggest increased diagnostic activity for asthma, but may also suggest that the asthma prevalence has continued to increase. In contrast to asthma, the prevalence of COPD tended to decrease and moderate to severe COPD decreased substantially. The continuous decrease in smoking in Sweden during several decades prior to the study period is most likely contributing to these results. The evaluation of reference values showed that the GLI reference values were lower than the observed spirometric values in the population, especially for women, why the new up-to date reference values may be of importance for disease evaluation in epidemiology and in the health care as well.
4

Interpretation of diagnostic information given patient characteristics /

Gellerstedt, Martin, January 2006 (has links)
Diss. (sammanfattning) Göteborg : Göteborgs universitet, 2006. / Härtill 5 uppsatser.
5

Biochemical Reference Intervals in Geriatrics / Biochemical Reference Intervals in Geriatrics: A Systematic Review and Examination of the Influence of Morbidity on Creatinine Reference Intervals

Arseneau, Erika 11 1900 (has links)
Reference intervals are important estimates used to determine whether an individual is healthy or unhealthy. They are the most widely used decision making tool in medicine and heavily influence doctor’s decisions regarding patient care. Despite the abundance of reference interval research in the field of clinical chemistry, age-related reference intervals have yet to be well-established for elderly populations. Many physiological and biochemical changes have been documented to occur with age however limited attempts have been made to quantify these changes. As a result, it is typical in clinical practice to assess geriatric patient data using an adult reference interval. Such practices can result in over-medicalization, unnecessary medical procedures and/or missed diagnoses. This thesis aims to address this gap in literature by summarizing what geriatric reference intervals are available and by investigating how reference intervals are affected by the presence of morbidity, a common characteristic of the elderly. The first chapter of the thesis introduces the reader to reference intervals, summarizes the current guidelines used in their determination and provides a rationale for the use of age-related reference intervals in geriatrics. Chapter 2 presents a systematic review that summarizes all available reference intervals for populations ≥65 years of age and the methodology used in their determination. Despite extreme variability in methodology, evidence suggests that geriatric reference intervals are significantly different from those of adults for many analytes. Chapter 3 presents a study that evaluates the effect morbidity has on reference intervals. In this study data from the National Health and Nutrition Examination Survey (NHANES) was used to calculate age-specific reference intervals for creatinine, a marker of kidney function known to increase with age. Findings suggest that the presence of morbidity significantly increases the upper limit for creatinine in elderly populations. Finally, the concluding chapter summarizes the overall findings of the thesis, proposes areas for future research and reinforces the importance of the above findings. / Thesis / Master of Science (MSc) / Reference intervals are estimates used to determine whether an individual is healthy or unhealthy. In particular this thesis investigates reference intervals for blood test results. Currently no age-specific reference intervals for the elderly are used clinically, instead the normalcy of a blood test result for an elderly person is based on adult reference intervals. This process may lead to over-medicalization or missed diagnoses in geriatrics. Within this thesis is a systematic review of the literature that was performed to capture any available reference intervals that have been published for populations greater than 65 years of age. It was determined that a multitude of geriatric reference intervals are available in literature but they are not used clinically and have no standardized methodology for their determination. Despite this lack of standardization, studies proved that geriatric reference intervals are significantly different from those of adult populations. Given that morbidity or the presence of disease is common in older patients it was suspected this may be a reason for the difference in reference intervals. A separate study was then performed to determine whether the presence of disease affects reference interval calculations. Results from this study showed that the presence of disease affects reference intervals in older individuals more so than younger individuals.
6

The normal range of the leukocyte count : implications for surveillance of occupational and environmental exposure and the practice of preventive medicine.

Cropper, Charles Austin. Delclos, George L. Escobar Chaves, Soledad Liliana. January 2008 (has links)
Thesis (M.P.H.)--University of Texas Health Science Center at Houston, School of Public Health, 2008. / Source: Masters Abstracts International, Volume: 46-04, page: 2059. Adviser: George L. Delclos. Includes bibliographical references.
7

Physiological monitoring of welfare for conservation of Arabian oryx, Oryx leucoryx

Al Jahdhami, Mansoor January 2010 (has links)
The endangered Arabian oryx, Oryx leucoryx faces a wide range of issues that potentially have adverse effects on their welfare while they are free-ranging in their natural habitat, housed in captivity for conservation breeding or when they are translocated from the wild to captivity or vice versa. Furthermore, the global increase in the number of captive Arabian oryx (currently more than 95 % of the world population of about 8000 individuals), gives rise to particular concern for their welfare and health within captive conditions. Thorough assessment of the welfare of animals involves physiological and behavioural measures. Methods for assessment of welfare in Arabian oryx have not been established and the present studies aim at establishing physiological tools for assessment of welfare. Therefore, the present studies developed and applied new methods for non-invasive assessment of welfare in the Arabian oryx (using faecal samples), and established reference values for a range of haematological, biochemical and clinical parameters. The potential disturbances in these parameters were investigated after immobilisation and tranquillisation and post- transportation. Two enzyme immuno-assays (EIA I and II) for faecal glucocorticoid metabolites (FGM) were validated by stimulation and suppression of the hypothalamic-pituitary-adrenal axis through injection of synthetic adrenocorticotropic hormone (ACTH) and dexamethasone, respectively. These studies established a lag-time of 14 ± 1 h between secretion of glucocorticoids into the blood stream and excretion of the measured FGM. Faecal incubation at 30°C for 3 days showed that EIA I measured more stable faecal glucocorticoid metabolites than EIA II, and has greater potential for application in field conditions. This method was found to be invaluable for measuring stress and hence assessment of welfare status, and its use is recommended in planning welfare improvements. Measurement of FGM successfully detected the stress of road transportation (630 km for 8-10 h), showing an increase 2 days after transport, followed by recovery to basal FGM levels after re-housing for up to 11 days. Releasing oryx to the wild, in Oman, and tracking for 11 days, after transportation 50-70 km from the captive site (Arabian Oryx Sanctuary, Jaaluni), caused an increase in FGM to the highest levels seen in these studies, and suggests a high level of stress was experienced after release of oryx. Published reference values for haematological, biochemical, hormonal and clinical parameters for Arabian oryx are limited, with little information for non-immobilised and non-tranquillised oryx or consideration of possible age and sex differences. Therefore, reference values and inter-percentile ranges (2.5 and 97.5 percentiles) were established for 32 parameters, in separate groups of male and female adult oryx, without using immobilising or tranquillising chemicals during capture. The haematological parameters investigated were white blood cell count and differentiation (%) of cell types (neutrophils, lymphocytes, monocytes, eosinophils, basophils), number of platelets, red blood cell count, haemoglobin concentration and haematocrit, erythrocyte cell volume, erythrocyte haemoglobin content and concentration, serum osmolality and ions (sodium, potassium, chloride, calcium, magnesium and phosphorus). Biochemical parameters investigated were serum urea, glucose, total protein, albumin and plasma lactate concentrations. Clinical parameters investigated were body temperature, heart and respiratory rates. Hormonal parameters measured were cortisol, free-thyroxine, free-triiodothyronine and insulin concentrations. Near basal values for serum cortisol were measured in Arabian oryx sampled within 2 min, while values were significantly higher in oryx sampled within 5-10 min. The reference values established in these studies are considered valuable tools for diagnosis of disease and physiological alterations in male and female Arabian oryx. To investigate the possible effects of the common practice of immobilisation and tranquillisation on physiological and biochemical status, two restraint chemicals (xylazine and perphenazine enanthate) were evaluated. Xylazine (an immobilising agent) caused changes in many clinical, hormonal, haematological and biochemical parameters; respiratory rate decreased by 74 %, heart rate decreased by 58 %, causing a decrease in red blood cell count, haemoglobin concentration and haematocrit, serum albumin and total protein concentration. Xylazine also induced a decrease in serum insulin, which probably caused the observed increase in serum glucose. Perphenazine enanthate (a long-acting tranquilliser) was found to have no adverse effects on most parameters, which generally remained in the reference ranges. However, a reduction in blood haematocrit and related parameters (red blood cell count and plasma haemoglobin concentration) occurred, 1-3 days after injection. The tranquilliser also plays a role in reducing stress and significantly reduced serum cortisol 2-3 days after injection in oryx held in captivity compared to oryx that received a saline (control) injection. FGM increased significantly one day after injection of perphenazine enanthate and saline, suggesting the animals were initially stressed by the handling and venipuncture, taking into consideration the lag-time from cortisol secretion to appearance of FGM. The baseline concentration of serum cortisol was used in assessing the stress caused by handling before and after transporting Arabian oryx for 630 km (8-10 h) and the acute effects of handling and injections. Increased serum cortisol was always associated with leukocytosis, neutrophilia and lymphopenia. Serum cortisol of non-transported oryx was reduced by the tranquilliser perphenazine enanthate, but transportation of tranquillised Arabian oryx during hot ambient temperature (maximum 42 °C) resulted in fatigue and prevented reaching a clear conclusion of the role of the tranquilliser in reducing transport stress. Non-tranquillised oryx transported at a maximum of 26-30 °C showed a similar level of stress as implied by the level of faecal glucocorticoid metabolites, but without fatigue. However, the tranquilliser induced calmness in Arabian oryx for up to 7 days, which facilitated capture and handling. Therefore, perphenazine enanthate has a potential to be used in the management practices, such as movement and transport of Arabian oryx. This thesis discusses the current and future welfare issues that face Arabian oryx in captivity, upon release and in the wild. Additional methods are proposed for thorough assessment and improvement of welfare to complement the methods established by the present studies.
8

Spirometrické měření studentů v závislosti na sportovní výkonosti / Spirometric Parameters of Students Depending on Their Physical Activity

Nedbalová, Jana January 2013 (has links)
The present work aims to answer questions regarding lung function among students of two types of grammar schools and describe selected indicators of differences between different groups of students within a reference population. The starting point for this work was speculation that the obligations defined by seconadary education in the ordinary type of school may significantly affect the students of the same age group and same Framework educational program for intensive regime of movement, breathing function. Is it possible that the secondary school educational program could affect the degree of respiratory function of students, for example by having less time and not having time for regular exercise? Are students of common type of grammar school physically less active than their peers from sports-oriented type of school? What are lung volumes of today's teens and how much do they differ from the current standards? The selection of respondents was elected from the students of sport-oriented grammar school and the common type of secondary school students. A total of 196 students participated in the study. Students were measured by spirometry lung capacity and function through painstaking cast in relation to strenuous breath. I have found that ordinary secondary school students have a positive...
9

Valores de referência de elementos em sangue de cavalos da Raça Crioula via metodologia nuclear / Reference values in blood elements in Crioula breed horses by nuclear methodology

Baptista, Tatyana Spinosa 01 October 2010 (has links)
No presente estudo valores de referência para Br (0,0008 - 0,0056 gL-1), Ca (0,089 - 0,369 gL-1), Cl (2,10 - 3,26 gL-1), Fe (0,381 - 0,689 gL-1), I (0,00018 - 0,00266 gL-1), K (1,14 - 2,74 gL-1), Mg (0,030 - 0,074 gL-1), Na (1,36 - 2,80 gL-1), P (<1,99 gL-1), S (0,99 - 2,79 gL-1) e Zn (0,0012 - 0,0048 gL-1) bem como a matriz de correlação em sangue de eqüinos da Raça Crioula foram determinados utilizando metodologia nuclear (técnica de Análise por Ativação com Nêutrons). Estes dados permitiram identificar alterações fisiológicas relacionadas ao gênero e regime de exercício em que se enquadram estes animais (produção de soros hiperimunes no Instituto Butantan, São Paulo, Brasil). Para realização dessas análises foram utilizados 20 cavalos adultos (8 machos e 12 fêmeas) sadios, na faixa etária de 1 a 3 anos e peso médio de 350 kg, mantidos na Fazenda São Joaquim do Instituto Butantan (São Paulo). Outro grupo recém imunizados, composto por 6 cavalos machos (mesmo peso e idade) foram também analisados. Estes dados auxiliaram na interpretação das funções fisiológicas desses elementos no sangue destes animais durante o processo de imunização para produção de soros. / In this study the reference value for Br (0,0008 - 0,0056 gL-1), Ca (0,089 - 0,369 gL-1), Cl (2,10 - 3,26 gL-1), Fe (0,381 - 0,689 gL-1), I (0,00018 - 0,00266 gL-1), K (1,14 - 2,74 gL-1), Mg (0,030 - 0,074 gL-1), Na (1,36 - 2,80 gL-1), P (<1,99 gL-1), S (0,99 - 2,79 gL-1) and Zn (0,0012 - 0,0048 gL-1) as well as the correlation matrix in blood of Crioulo breed horses were determined using nuclear methodology (Neutron Activation Analysis Technique). These data allowed to identifying physiological alterations related to the sex and regime of exercise (hyperimmune sera production at Butantan Institute, São Paulo, Brasil). To perform these analyses was used 20 adult horses (8 males and 12 females), with average mass 350 kg, without clinical signs of disease, 1-3 years old, kept on pasture in São Joaquim Farm at Butantan Institute (São Paulo city). Other group just immunized, composed by 6 equines males (same age and weight), were also analyzed. These data are an important support to understand the physiological functions of these elements in blood during the process of sera production.
10

Valores de referência para metais potencialmente tóxicos em sedimentos e em moluscos filtradores no Rio Ribeira de Iguape / Reference values to potentially toxic metals in sediments and mussels in the River Ribeira de Iguape

Martins, Letícia Manolio de Paula 20 June 2012 (has links)
O alto da Bacia Hidrográfica do Rio Ribeira de Iguape foi submetido a intensa atividade mineira, cujo objeto mineral principal era a obtenção de chumbo (Pb). Durante longo período as condições de explotação foram rudimentares, não havendo controle sobre o impacto ambiental gerado durante as fases de extração e beneficiamento do minério, cujos rejeitos (escória e concentrado) foram lançados por anos diretamente no rio Ribeira de Iguape. Com o propósito de se criar uma indicação clara do comprometimento ambiental ou não da bacia hidrográfica do rio Ribeira de Iguape quanto ao teor dos metais Cd, Pb, Cr, Zn e Cu, este trabalho exibe resultados de valores que podem servir de referência em teor para estes metais. Para tanto, foram coletadas amostras de duas espécies de moluscos bivalves, Anodontites tenebricosus e Corbicula fluminea e de sedimento aluvionar, em uma porção localizada a montante das fontes de contaminação pelas atividades de mineração e fundição. Os moluscos foram coletados por exame tátil do substrato, seus tecidos foram separados das conchas, liofilizados e analisados em espectrômetro de massa (ICP/MS) e em espectrômetro de absorção atômica (AES). Os valores médios foram em sua maioria inferiores aos valores obtidos por outros autores em pontos localizados ao longo do rio Ribeira de Iguape sob a influência das atividades de mineração e fundição. Em relação às amostras de sedimento aluvionar estas foram separadas em duas porções, uma contendo sedimentos com minerais não magnéticos e a outra sedimentos com minerais magnéticos. Estas amostras foram tratadas granulometricamente e analisadas por fluorescência de raio X (FRX), a fim de se obter a concentração dos metais contidos em cada fração granulométrica. Nas amostras de sedimento não magnético, o composto químico em maior concentração foi SiO2. Quanto aos metais potencialmente tóxicos aqui investigados, todos foram encontrados nestas amostras. Já em relação ao sedimento magnético, as amostras exibiram constituição química composta principalmente por Fe2O3. Os metais Pb, Cr, Zn e Cu, foram encontrados em maior concentração nas amostras referentes as frações granulométricas mais finas, sendo a concentração do Cr nitidamente mais elevada. A elevada concentração deste metal nas amostras de sedimento magnético, quando comparada com as obtidas nas amostras não magnéticas, pode indicar uma provável origem do Cr a partir do mineral cromita (FeCr2O4). Estes dados juntamente com informações contida na literatura específica, indicam que provavelmente a origem do Cr, Pb, Zn e Cu na bacia do rio Ribeira de Iguape possui origem geogênica. De maneira geral, as concentrações dos metais potencialmente tóxicos aqui verificadas, tanto nas amostras referentes às duas espécies de moluscos quanto nas amostras de sedimentos, são inferiores, em sua maioria, às obtidas em pontos ao longo do rio Ribeira de Iguape estudados por outros autores onde há influência das atividades de mineração, o que permite considerar esses dados como referência. / The Ribeira do Iguape River Basin (RIRB) was historically influenced by intense mining activities mainly related to lead (Pb) extraction. For many decades, such exploitation was conducted under rudimentary conditions without control of environmental impacts produced during the stages of ore extraction and beneficiation. Thus, mining wastes and metallurgical slags were directly discharged into the Ribeira de Iguape River, causing environmental contamination by metals. The present investigation has the purpose of developing reference values to some metals (Cd, Pb, Cr, Zn and Cu) to RIRB, in order to provide information that allow the environmental monitoring and the determination of environmental contamination to Ribeira do Iguape River Basin. To achieve that, samples of two bivalves species were collected: Corbicula fluminea and Anodontites tenebricosus. Besides, alluvial sediments from a site located upstream to the contamination sources for metals (mining and smelting activities) were also collected. For both species, soft tissues were firstly separated from their respective shells, freeze-dried and then analyzed in a mass spectrometer (ICP/MS) and atomic absorption spectrometer (AAS). Alluvial sediment samples were splitted into two aliquots, one containing magnetic minerals and another with sediment containing non-magnetic minerals. These samples were separated for particle size and analyzed by X-ray fluorescence (XRF) in order to obtain the metals concentrations for each class of particle size. For presence of metals in bivalves, concentrations were mostly lower than those reported by other authors along RIRB areas influenced by mining and smelting residues. In the non-magnetic sediment fraction, the prominent substance was SiO2. Regarding to potentially toxic metals investigated in this study, all of them were found in such samples. On the other hand, in the magnetic sediment fraction, the prominent chemical was Fe2O3. Pb, Cr, Zn and Cu were found in highest concentrations in the finer grain fractions. The Cr concentration was noticeably high. The higher concentration of this metal in magnetic sediment fractions, when compared to the non-magnetic ones, may indicate a probable source of Cr, Pb, Zn e Cu from the mineral chromite (FeCr2O4). These data, together with that from specific literature, indicate that the origin of Cr at RIRB is probably natural .In general, the potentially toxic metals concentrations found in this study for both species of mussel and sediment are mostly lower than the concentrations obtained by others authors for other portions of Ribeira de Iguape River under influence of mining activities, thus, such results suggest that these concentrations may be considered as local reference values for RIRB.

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