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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

Analysis and comparison of blood lead risk area models for selected urban areas in Indiana

Zhao, Yunzhong. January 2009 (has links)
Although much progress has been made in the United States, childhood lead poisoning remains a critical environmental health problem. Lead causes many problems such as learning disabilities, coma, and even death. Many studies have focused on these problems in the last three decades, but Geographic Information System (GIS) technology has only been employed since the 1990s. In addition, no research has examined the differences among the models based on the different geographic locations and size of cities. In this study, screening results of childhood lead levels in Indiana are evaluated based on a census tract geography. The relationship between the number of children less than six years old with elevated Blood Lead Levels (BLLs) and social-economic factors such as percentage of children in poverty and age of housing stock are examined for selected urban areas in Indiana. Stepwise and backward elimination are used to choose the independent variables and least squares regression methods are used to build evaluation models according to the location and size of urban areas in Indiana. Finally, a comparison is made among these models to examine whether there is any difference according to city size and location, and whether a state level model would be suitable for the selected urban areas. The results show that backward elimination is a better way to select the independent variables in most of the models. The census tracts with high value of residuals are located in the outer periphery of most urban areas. For some models, the residuals are lower in the census tracts with a high ratio of children screened. The results also manifest that some of the same parameters exist in the models of the same urban size or location in Indiana and geographic factors could be potential elements in building model for children’s EBLLs. None of the models have exactly the same parameters. In addition, the comparison shows that the state model is not as accurate as the urban area models. How to balance the weakness of both state model and urban area model could be an extension for further study. / Department of Geography
42

Oxytocin and oxytocic substance in blood and hypothalamus : being an investigation of (a) oxytocin and oxytocic substance in extracts of blood and hypothalami : and (b) and "enzyme" in blood and placental extracts which destroys oxytocin, antidi

Hawker, Ross Wilson, d. 1996. Unknown Date (has links)
No description available.
43

Oxytocin and oxytocic substance in blood and hypothalamus : being an investigation of (a) oxytocin and oxytocic substance in extracts of blood and hypothalami : and (b) and "enzyme" in blood and placental extracts which destroys oxytocin, antidi

Hawker, Ross Wilson, d. 1996. Unknown Date (has links)
No description available.
44

The physiological effect of vitamin B12 deficiency in human blood

Abel, Stefan 11 1900 (has links)
Thesis (MSc) -- Stellenbosch University, 1990. / ENGLISH ABSTRACT: The main aim of this workpiece was to establish the physiological parameters against which a vitamin Bu deficiency could be measured. A comparison between the hematological values of healthy patients and those suffering from pernicious anemia due to vitamin Bu deficiency was done. A specific case of pernicious anemia was used in the comparison of abnormal values to the values of normal healthy patients. The comparison consisted of blood analyses with the help of specified instruments, photomicrographs of bone marrow and blood smears and statistical data. A Coulter Counter Model ZF was used for the hematological analyses of blood, a radio-isotope assay for serum vitamin B u was done and photomicrographs were taken with a NIKON Microflex camera with photomicrographic attachments. The importance of vitamin Bu has been shown in this workpiece. With the use of techniques and certain instruments, the effects of a shortage of vitamin Bu has been shown. Analyses of the blood from normal ,healthy patients was compared to that of patients suffering from pernicious anemia. It was demonstrated that pernicious anemia is characterized by a low erythrocyte count, hematocrit (Het), hemoglobin (Hb) and vitamin Bu levels together with a higher mean corpuscular hemoglobin (MCH) and mean corpuscular volume (MCV). In severe cases of pernicious anemia these levels are extremely high or low as the case may be. Together with these values, the investigation of pernicious anemic blood and bone marrow smears revealed abnormally large erythrocyte precursors and fewer leucocytes than normal. Abnormally shaped cells, called macrocytes, were seen which was due to the disruption in deoxyribonucleic acid (DNA) synthesis caused by the vitamin Bu deficiency. This study produced a set of hematological reference values. The comparative study between healthy and pernicious anemic patients demonstrated a significant drop in serum vitamin B12 values during pernicious anemia. The hematological effect was illustrated by the Coulter Counter blood analysis results and the microscopic examination revealed the presence of megaloblastic erythrocytes, oval erythrocytes, pear-shaped poikilocytes and polymorphonuclear neutropbils with hypersegmented nuclei in blood smears I during vitamin B12 deficiency. This dianoses can be supported by the presence of megaloblasts and metamyelocytes in pernicious anemic bone marrow. / AFRIKAANSE OPSOMMING: Die hoof doel van hierdie werkstuk was om fisiologiese grense te bepaal waarteen 'n vitamien B12 tekort gemeet kan word. 'n Vergelyking tussen die hematologiese waardes van gesonde persone en die van pasiente met pernisieuse anemie wat ontstaan het as gevolg van 'n vitamien B12 tekort was uitgevoer. Die waardes verkry vanaf 'n spesifieke geval van pernisieuse anemie. was vergelyk met waardes vanaf normale gesonde persone. Hierdie vergelyking het bestaan uit bloed analises, fotomikrograwe van bloed en beenmurg smere en statistiese data. Die hematologiese bloed analises was met behulp van 'n Coulter Teller model ZF uitgevoer. 'n Radio-isotoop bepaling vir serum vitamien B12 was gedoen en fotomikrograwe was met 'n NIKON Microflex kamera geneem. Die belang van 'n vitamien B12 tekort was in hierdie werkstuk gedemonstreer. Die effek van hierdie tekort is deur die gebruik van sekere instrumente en tegnieke aangedui en die resultate hiervan is vergelyk tussen gesonde persone en pasiente met 'n vitamien B12 tekort. Hierdie studie het bevestig dat pernisieuse anemie gekenmerk word deur verlaagde eritrosiet, hematokrit (Het), hemoglobien (Hb) en vitamien B12 vlakke tesame met verhoogde gemene korpuskulere hemoglobien (GKH) en gemene korpuskulere volume (GKV) vlakke. Gedurende ernstige gevalle van pernisieuse anemie kan hierdie waardes uitermatig hoog of laag wees. Benewens hierdie waardes het die ondersoek van bloed en beenmurg gedurende vitamien B12 tekort, abnormale groot eritrosiet voorgangers en 'n verminderde hoeveelheid leukosiete getoon. Abnormale sel vorms was ook sigbaar a.g.v. die onderbreking in DNA sintese wat deur 'n vitamien B12 tekort veroorsaak word. Pernisieuse anemie word verkry wanneer daar 'n vitamien B12 en/of folaat tekort in die dieet is of wanneer hierdie vitamiene nie geabsorbeer kan word nie. Die teenwoordigheid van makrosiete, ovaal eritrosiete, peervormige poikilosiete en polimorfonuklere neutrofiele met hipergesegmenteerde keme in bloedsmere dui op 'n megaloblastiese anemie. Hierdie diagnose kan ondersteun word deur die aanwesigheid van megaloblaste en reuse metamielosiete in die beenmurg. Die bepaling van vitamien B12 en folaat vlakke in die bloed kan as addisionele bewysstukke vir 'n volledige diagnose dien. Gedurende hierdie studie is daar 'n stel hematologiese verwysingswaardes vasgestel. Die vergelykende studie tussen gesonde persone en pasiente met pernisieuse anemie het getoon dat daar 'n beduidende verlaging in serum vitamien B12 waardes gedurende pernisieuse anemie is. Die hematologiese effek was ook duidelik waameembaar in die Coulter teller se bloed analiese en mikroskopiese ondersoeke het die · teenwoordigheid van makrosiete, ovaal eritrosiete, peervormige poikilosiete en polimorfenuklere neutrofiele met hipersegmenteerde keme in bloedsmere aangedui. Hierdie diagnose kan ondersteun word deur die aanwesigheid van megaloblaste en reuse metamielosiete in die beenmurg. / This study was financially aided by a bursary from the CSIR.
45

Foetal acid-base status and foetal electrocardiography [microform] / by Edwin Malcolm Symonds

Symonds, E. M. (Edwin Malcolm) January 1970 (has links)
Bibliography: leaves 284-298 / 4 microfiches (339 fr.) : / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Summary: Shows that foetal acidosis is related to prolongation of the QT interval, a change which cannot be accounted for in foetal heart rate. Describes the configuration and time constants of the foetal electrocardiogram both during labour and at the time of delivery in normal and acidotic subjects. Confirms that foetal acidosis during labour is associated with acidosis at the time of delivery and with clinical depression of the newborn infant / Thesis (M.D.)--Dept. of Obstetrics and Gynaecology, University of Adelaide, 1970
46

Real-time RNA-based amplification allows for sensitive forensic blood evidence analysis / Real time ribonucleic acid based amplification allows for sensitive forensic blood evidence analysis

Counsil, Tyler I. January 2008 (has links)
The purpose of this experiment was to determine if nucleic acid sequence based amplification (NASBA) is a suitable application for the differentiation of body fluids that might comprise a forensic evidence sample. NASBA is a sensitive RNA transcription based amplification system. NASBA could theorhetically be used for bodily fluid identification based upon amplification of tissue-specific mRNA transcripts present in a given forensic sample.Amplification of both Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and Matrix Metalloproteinase 1 1 (MMPmRNA transcripts were used to determine that NASBA could amplify body fluid transcripts and whether it could distinguish between menstrual and non-menstrual blood, respectively. GAPDH is a housekeeping gene that is constituently expressed and its mRNA transcripts could therefore be used to determine whether non-menstrual blood could be amplified using the NASBA procedure. MMP 11 is a menstrual cycle-specific gene associated with endometrial breakdown. Using the mRNA transcripts from MMP 11, NASBA could be utilized for menstrual blood identification. In this study, non-menstrual and menstrual blood samples were analyzed with NASBA both in the presence and absence of chemical contamination. Contaminants utilized ranged from commercial automotive wax, transmission fluid, brake fluid, artificial tears, hand soap, 10% bleach, and the luminol blood detecting reagent. Non-menstrual blood was aliquoted onto a 1 cm x 1 cm cotton cloth for contamination, while menstrual blood was provided on a 1 cm x 1 cm area of sterile menstrual pad. All samples underwent Tri reagent extraction to obtain RNA samples for NASBA amplification.With respect to NASBA amplification data, non-menstrual blood data (from extracted RNA and unextracted blood samples) revealed the highest levels of amplification as shown in relative fluorescence units (RFU). Uncontaminated menstrual blood revealed the second highest amplification data. In the presence of chemical contamination, high levels of amplification were observed when samples were contaminated with brake fluid and commercial hand soap. Moderately low amplification was observed with samples contaminated with transmission fluid, 10% bleach, and artificial tears. NASBA amplification was completely inhibited in the presence of automotive wax and luminol. Cycle threshold (CO values for each amplification result were also obtained from each reaction. Smaller Ct values correspond to a higher NASBAreaction efficiency and therefore larger amplification values. The Ct values obtained for each amplified sample correlate strongly with the amount of amplification observed from reaction. Based upon the results of this experiment, NASBA should be considered as a novel tool for forensic evidence analysis. / Department of Biology
47

Die bepaling van sekere plaagdoderreste in die bloed van plaaswerkers op appelplase in die Elgin-distrik

Morren, Carel-Jan Hendrikus January 1994 (has links)
Thesis (Masters Diploma (Technology)--Cape Technikon, Cape Town,1994 / Pesticides are generally used in south-Africa for the control of various pests; from insects and fungi to weeds. The agricultural industry is probably the biggest user of pesticides and therefore workers in this part of the labour force have the biggest risk of being exposed to the hazards of these essential products. During the 1988/89 deciduous fruit season the deciduous fruit industry earned approximately R1000 million in foreign exchange. It is therefore very important for this industry to produce fruit of high quality in a very competitive market. Of the total deciduous exports, apples comprised approximately 62,5%. The EIgin-Grabouw area is the biggest producer of apples. This industry is clearly very dependant on pesticides to protect its crops against pests. From time to time farm - workers are exposed to pesticides, a study was therefore performed to access the levels of exposure of farm workers. Blood and urine samples were collected in a comprehensive biological monitoring program in the Elgin area to determine, uusing clinical tests, the level of exposure to pesticides. It was decided later that the determination of pesticide residues in blood would form part of this main study. Other tests included serum and red cell cholinesterase. Samples were collected during August (start of spraying season), November (midseason) and February (end of spraying season). A multi-residue method was developed to extract organophosphate and organochlorine pesticides in whole blood. Although various methods exist, they allow only for the extraction of either organophosphates or organochlorines and not multi-residue extractions. This multi-residue method is based on the liquid/liquid extraction of a blood/Celite/ethanol mixture to extract the following pesticides: Azinphos-methyl, Chlorpyrifos, Endosulfan, Methidathion and Prothiophos. The pesticide residue levels were determined on gas chromatographs equipped with DB-5 and DB-2I0 capillary columns and flame photometric-, electron capture- and nitrogen/phosphorous detectors. The results were confirmed on a gas chromatograph with mass-selective detector in selective ion mode. Of the 402 blood samples analysed, 23 samples showed positive for organophoshates and 29 for organochlorines, and were sent for analysis on the mass spectrometer. Of those samples only one could be positively identified. The presence of the pesticide Endosulfan-B was confirmed. The confirmation of the pesticides was complicated by interfering substances that leached from the rubber stoppers of the collection vessels into the blood. Although the study showed that for practical purposes no pesticides were present, other important information was obtained about the handling and analyses of blood samples for pesticides.
48

Efeito do consumo de peixes gordurosos amazônicos sobre o metabolismo lipídico de ratos wistar.

Souza, Francisca das Chagas do Amaral 04 August 2006 (has links)
Made available in DSpace on 2015-04-20T12:31:39Z (GMT). No. of bitstreams: 1 - PDF.pdf: 156224 bytes, checksum: d8d6c26c25fefd22c60ea2b135c6dbc3 (MD5) Previous issue date: 2006-08-04 / Fundação de Amparo à Pesquisa do Estado do Amazonas / Obesity is a disease that occurs due to the unbalance between the ingested energy and the spent energy to maintain the vital processes. Obesity has incresingly wrong and reached, nowadays, and epidemic level. It has also been considered the main public health issues in modern society. It is asociated with the rising risk of developing Diabetes Melliteus, cardiovascular diseases, dislipodemia, and several other chronic diseases. The diet based on fat maybe crucial reason to develop such diseases. The fishing also provides a large sort of food to thousands of local inhabitants nutrional development. Among the most well-known and consumed Amazon fish there is Tambaqui (Colossoma macropomum), Matrinxã (Brycon cephalus) and Mapará (Hypophthalmus edentatus), which are all considered very fat species. And so, the main purpose of this essay is to analyse the effects of a diet based on Amazon fat fish (Mapará, Matrinxã and Tambaqui) on male mice lipydic metabolism from wistar blood line. They were feeded with Adlibitum for 14 days. To make it happen doses of total cholesterol and triglycerids, glycoses, proteins and plasma lipydic fraction were made. The rate of lypogenesis again in vivo has been measured on RET, EPI, FIG and CARC, by incorporating 3 H2O in lipy. Our results show that the enrichment of a diet based on Amazon fat fish has altered the mice lipydic metabolism, dicreased effectively the lipid plasmatic concentration (Col. TG, e LDL) and increased the HDL besides the lipolitic activity on fatty tissues has grown after 4 weeks of feeding. Admiting that the ingestion of hiperlipydic diets may have caused an aterogenic effect, mainly because they have reduced certain lipydic fractions that have been claimed to cause serious vascular problems. / A obesidade é uma doença que ocorre como conseqüência do desequilibro no balanço entre energia ingerida e a gasta para a manutenção de processos vitais. A obesidade possui prevalência crescente, assumindo atualmente caráter epidêmico, sendo considerada um dos principais problemas de saúde pública na sociedade moderna. Ela está associada com o aumento do risco de desenvolve diabetes mellitus, doenças cardiovasculares, dislipidemias e inúmeras outras doenças crônicas. As dietas ricas em lipídios podem ser um fator determinante para o desenvolvimento de tais doenças. A pesca contribui na oferta de alimentos e para o desenvolvimento nutricional de milhares de habitantes da região. Dentre os mais conhecidos e consumidos peixes da Amazônia estão o tambaqui (Colossoma macropomum), a matrinxã (Brycon cephalus) e o mapará (Hypophthalmus edentatus), os quais são consideradas espécies bastante gordurosas. Desta forma objetivo deste trabalho foi avaliar os efeitos da dieta de peixes gordurosos (mapará, matrinxã e tambaqui) da Amazônia sobre o metabolismo lipídico de ratos machos da linhagem wistar. Assim foram alimentados ad libitum por 30 dias. Para tanto foram realizadas as dosagens de colesterol total e triglicérideos, glicose, proteínas e frações lipídicas do plasma. a taxa de lipogênese de novo in vivo foi medida nos tecidos RET, EPI, FIG e CARC, por meio da incorporação de 3H2O em lipídios. Nossos resultados mostram que o enriquecimento da dieta com peixes amazônicos gordurosos alterou o metabolismo lipídico dos ratos, diminuindo de forma efetiva a concentração plasmática de lipídios (Col. TG, e LDL) e aumentando o HDL. Além disso, a atividade lipolítica nos tecidos adiposos aumentou após 4 semanas de alimentação. Sugerindo que a ingestão de dietas hiperlipídicas pode ter efeito aterogênico, principalmente, por diminuírem determinadas frações lipídicas, que tem sido responsabilizada por causar graves problemas vasculares.
49

Postsynthetic Modifications of Glycolytic Enzymes of the Geriatric Immune System and in Fibroblasts from Premature Aging Diseases

Tollefsbol, Trygve O. 08 1900 (has links)
During mitogen-induced transformation of human lymphocytes, phosphoglycerate kinase (PGK) exhibits new electrophoretic forms (pl=8.5-8.9). Electrophoresis and electrofocusing showed that the new forms are not due to expression of the autosomally linked isozyme found in semen (PGK-B; pl=9.7). The multiple electrophoretic forms are the result of protease modification of sex-linked PGK-A isozyme.When peripheral lymphocytes from young persons are stimulated in vitro with phytohemagglutinin, a selective increase in the levels of the glycolytic enzymes occurs concomitantly with blastogenesis. Human lymphocytes from a geriatric population were also subjected to mitogen stimulation. The initial levels of the enzymes were essentially identical in lymphocytes from young and old subjects as were mitogenfree cultured controls. However, during mitogen stimulation the cells from the old subjects failed to increase the glycolytic enzymes. This inability to activate glycolysis may be related to the decline in cell-mediated immunity which occurs with advancing age. Triosephosphate isomerase (TPI) has an increased thermolabile component in skin fibroblasts from patients with progeria (41.4 per cent)and Werner's syndrome (20.1 per cent) when compared with normal fibroblasts (0-3 per cent). The incorporation of various protease inhibitors failed to affect the percentages of heat-labile triosephosphate isomerases. The labile component appears to be identical to the deamidated form of the enzyme which accumulates in other aging cells. Isoelectric focusing demonstrated increased quantities of the deamidated TPI-A form in progeria and Werner's syndrome fibroblasts as compared to normal. The deamidated TPI-A was considerably more labile than the native TPI-B indicating the increased lability of triosephosphate isomerase in premature aging syndrome fibroblasts is due to an accumulation of the deamidated form of the enzyme. The levels of several proteases were found to be diminished in progeria fibroblast extracts as compared to normal. A deamidation mechanism of enzyme degradation plays a key role in the normal cellular catabolism of this enzyme and the mechanism for accumulation of defective forms in aging cells is apparently exacerbated by an impaired proteolytic capacity.
50

Genetic variation in blood proteins within and differentiation between 19 sheep breeds from Southern Africa

Sargent, Janice 27 August 2012 (has links)
M.Sc. / The amount of allozyme variation within, and the extent of genetic differentiation between, 19 sheep breeds from southern Africa were determined by six enzyme coding loci. Another eight enzyme coding loci were analyzed for five breeds. Between 55 and 66.67% of the protein coding loci were polymorphic (95% criterion) in all the breeds, except for the Namaqua sheep that were less polymorphic (33.33%). Values of 1.67 to 2.5 were obtained for the mean number of alleles per locus and average heterozygosities per locus was between 16.6 to 35.9%. The allelic constitution particularly at the transferrin (TF) locus varied appreciably for the different breeds. For example, the TF*H allele was exclusively noted in the Dormer sheep and the TF*G allele was found in the Afiino, Van Rooy, Border Leicester, Blackhead Persian and Skilder-Persian breeds. The only polymorphic breeds at the albumin locus were the South African Mutton Merino and Van Rooy breeds. The allelic constitution at the other polymorphic loci was similar for the breeds, but the allele frequencies of the South African Merino differs from Merino breeds in other countries at the TF locus. Unbiased genetic distance values were the smallest between the Dorper and Dormer breeds and the largest between the Romenof and Blackhead Persian breeds, and the mean genetic distance between the 19 breeds was 0.067. The mean amount of differentiation among the breeds relative to ' the limiting amount under complete fixation (F st) was calculated at 0.123, which is an indication of small genetic differentiation between the breeds studied. However, this , statistic is not reflected by the allele distribution that was not identical for 25 breed pairs (15%) of the total (171) at all the genetic blood systems studied. None of the breed pairs showed identical allele distributions at all the loci studied for at least one locus differed at each breed pair compared. Random amplified polimorphic DNA's gave no consistent or repeatable results. The results of the allozyme study presents the first study of the current genetic characterization of the different southern African sheep breeds.

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