• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 331
  • 137
  • 39
  • 36
  • 31
  • 20
  • 19
  • 14
  • 12
  • 12
  • 4
  • 2
  • 2
  • 1
  • 1
  • Tagged with
  • 729
  • 81
  • 78
  • 72
  • 61
  • 61
  • 55
  • 54
  • 52
  • 52
  • 49
  • 48
  • 46
  • 45
  • 42
  • 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

Mise au point d'un test ELISA pour détecter les anticorps anti-Chlamydia pneumoniae

Boufaied, Nadia. January 2000 (has links)
Thèses (M.Sc.)--Université de Sherbrooke (Canada), 2000. / Titre de l'écran-titre (visionné le 20 juin 2006). Publié aussi en version papier.
2

Three surveillance systems for describing the spatial distribution of Johne's disease seropositivity in Texas cattle

Pearce, Brielle H. 15 May 2009 (has links)
Johne’s disease is a chronic and debilitating disease of cattle caused by infection with Mycobacterium avium subsp. paratuberculosis (Mptb). This disease affects both dairy and beef cattle, though it is more commonly recognized in dairy cattle. Mptb is able to persist in the environment of cattle for extended periods of time; therefore the distribution of the disease depends on the presence of infected animals and environmental conditions. Three surveillance systems were used to describe the spatial distribution of Johne’s disease seropositivity in Texas cattle. These three systems were hypothesized to describe different spatial patterns. These systems involved sampling, 1) herds throughout Texas, 2) market cattle from four markets each month (one each from northern, southern, eastern, and western regions of Texas) and 3) sick animals submitted by veterinarians throughout Texas. Samples were tested for Johne’s disease at the Texas Veterinary Medical Diagnostic Laboratory using serum ELISA. Spatial distributions were estimated by kriging the sample-to-positive control ratios (S/P). Sera were evaluated for Mptb antibodies from 2358 cattle with 1084 animals in system 1, 1200 from system 2 and 74 from system 3. Total number of positive ELISA results was 51, with 25, 19 and 7 positve ELISA results for systems one, two and three, respectively. Results showed an overall prevalence of 2.16%, and prevalence’s of 2.31%, 1.58% and 9.46% for systems one, two and three, respectively. Differences in the spatial distribution of Johne’s disease seropositvity, based on the three surveillance systems, confirmed our hypothesis that estimation of disease distribution is dependant upon the source of surveillance samples.
3

Target validation of a myokinin receptor from the southern cattle tick Boophilus microplus (Canestrini)

Blandon, Maria Adylia 17 September 2007 (has links)
A novel approach to control Boophilus microplus is to disrupt the physiological function of an endogenous myokinin receptor of this tick that was previously cloned in our laboratory. To test the hypothesis that this myokinin receptor might be a suitable target for development of a novel acaricide, this target was validated by immunological disruption. A mixture of peptides, corresponding to the sequence of the extracellular loops of this receptor which were synthesized and linked to a carrier protein, was injected into Hereford cattle to induce an immunological response. Immunological tests (ELISA) were developed to test the sera of these animals for antibody titers. The data were analyzed using a randomized block split plot design and were compared between the control (calves numbers 407, 408, 427, 436, and 438) and peptide-injected calves (calves numbers 417, 420, 421, 426, and 435). A gradual increase of antibody production was observed with the peptide-injected calves with bleed 4 showing the highest absorbances. Control calves and peptide-injected calves with high antibody titers were challenged with approximately 20,000 tick larvae at the USDA Cattle Tick Research laboratory. The tick challenge test determined that disruption of the receptor function produces a detrimental effect on tick physiology (development, feeding and reproduction) by looking at percentage of molting, time of survivorship, number of ticks dropped, weight of fed females, weight of egg masses, and blood meal conversion. The results, which were analyzed by a contingency table and a 2 sample T-test, did not support the hypothesis that the sera ingested from the peptide-injected cattle would cause a detrimental effect on tick physiology. There was no statistical significance in the percentage of metanymphs molting from peptide-injected calves versus control calves (p = 0.282) and in the time of adult survivorship. A statistical inference could be made about the number of ticks that dropped since four calves died of bovine babesiosis after the metanymphal collection. There was no statistical significance in the weight of fed females (p = 0.061), weight of egg masses (p = 0.885), and bloodmeal conversion (p = 0.312) from peptide-injected calves versus control calves.
4

The evaluation of the utility of bulk tank tests for the surveillance of Johne's disease and the effect of storage time and temperature on Johne's milk ELISA results

Innes, Carolyn 30 September 2011 (has links)
The first objective of this study was to evaluate the utility of bulk tank tests to detect the presence of Mycobacterium avium subspecies paratuberculosis (MAP) antibody in dairy herds for the purpose of Johne’s disease surveillance. Individual cow milk samples were collected by CanWest Dairy Herd Improvement customer service representatives in herds across Ontario, Canada. These samples, along with bronopol preserved bulk tank samples were collected from herds participating in the Ontario Johne’s Education and Management Assistance Program (OJEMAP), a producer funded Johne’s control scheme. Overall, there were 309 farms tested, with herd size from 15 to 986 milking cows. The relative sensitivity and specificity of the bulk tank ELISA test when a positive herd was defined as 1 or more positive cows was 54.7% and 90.6%, respectively. The second objective was to determine the effect of milk storage temperature and duration on the Johne’s milk ELISA test result. When herd level factors were considered in a logistic model, average monthly protein (%) and the percent of positive milk contributed to the bulk tank by milk ELISA positive cows were found to be significantly (p<0.05) associated with the probability of a herd testing positive on the bulk tank Hyper ELISA protocol. Positive and negative MAP milk samples were stored for varying times and under different temperature conditions. In a mixed linear model, time was found to be significantly (<0.001) associated with the log transformed ELISA optical density. When the results were dichotomized into positive and negative by the cut-off of 0.10 and cross classified, the amount of misclassification was considered biologically negligible.
5

Metallothionein in the acute phase response and in zinc deficiency in humans

Akintola, Durojaiye Funmilayo January 1995 (has links)
No description available.
6

Antibodies to acetylcholinesterase, their detection and clinical significance

Green, John January 1999 (has links)
No description available.
7

Humoral immune responses to the human hookworm Necator americanus in an endemic population

Walsh, Elizabeth A. January 1994 (has links)
No description available.
8

Target validation of a myokinin receptor from the southern cattle tick Boophilus microplus (Canestrini)

Blandon, Maria Adylia 17 September 2007 (has links)
A novel approach to control Boophilus microplus is to disrupt the physiological function of an endogenous myokinin receptor of this tick that was previously cloned in our laboratory. To test the hypothesis that this myokinin receptor might be a suitable target for development of a novel acaricide, this target was validated by immunological disruption. A mixture of peptides, corresponding to the sequence of the extracellular loops of this receptor which were synthesized and linked to a carrier protein, was injected into Hereford cattle to induce an immunological response. Immunological tests (ELISA) were developed to test the sera of these animals for antibody titers. The data were analyzed using a randomized block split plot design and were compared between the control (calves numbers 407, 408, 427, 436, and 438) and peptide-injected calves (calves numbers 417, 420, 421, 426, and 435). A gradual increase of antibody production was observed with the peptide-injected calves with bleed 4 showing the highest absorbances. Control calves and peptide-injected calves with high antibody titers were challenged with approximately 20,000 tick larvae at the USDA Cattle Tick Research laboratory. The tick challenge test determined that disruption of the receptor function produces a detrimental effect on tick physiology (development, feeding and reproduction) by looking at percentage of molting, time of survivorship, number of ticks dropped, weight of fed females, weight of egg masses, and blood meal conversion. The results, which were analyzed by a contingency table and a 2 sample T-test, did not support the hypothesis that the sera ingested from the peptide-injected cattle would cause a detrimental effect on tick physiology. There was no statistical significance in the percentage of metanymphs molting from peptide-injected calves versus control calves (p = 0.282) and in the time of adult survivorship. A statistical inference could be made about the number of ticks that dropped since four calves died of bovine babesiosis after the metanymphal collection. There was no statistical significance in the weight of fed females (p = 0.061), weight of egg masses (p = 0.885), and bloodmeal conversion (p = 0.312) from peptide-injected calves versus control calves.
9

Étude sur la colonisation des tissus de porc par Yersinia enterocolitica et mise au point d'une épreuve ELISA pour détecter les porcs porteurs de cette bactérie

Thibodeau, Valérie. January 2000 (has links)
Thèses (M.Sc.)--Université de Sherbrooke (Canada), 2000. / Titre de l'écran-titre (visionné le 20 juin 2006). Publié aussi en version papier.
10

Utvärdering av Malaria Antigen ELISA kit för diagnostik av malaria vid Christian Medical College and Hospital i Vellore, Indien. : en jämförande studie mellan Quantitative buffy coat och enzyme-linked immunosorbent assays (ELISA) metodik.

Andersson, Josefin January 2006 (has links)
Malaria är ett globalt hälsoproblem som orsakar många dödsfall runt om i världen varje år och nästan hälften av jordens befolkning ligger i riskzonen att drabbas av sjukdomen. I Indien drabbas mellan 2-3 miljoner människor varje år och det inträffar omkring 900 dödsfall. Malaria orsakas av Plasmodium sp. som är en protozoe, och det finns fyra olika arter som är patogena för människor, P. vivax, P. ovale, P. falciparium samt P. malariae. Vanliga metoder för att diagnostisera malaria är genom tunna och tjocka blodutstryk som färgas till exempel med Giemsa, Fields eller Leishmans färgningsteknik och studeras mikroskopiskt, Quantitative Buffy Coat (QBC), PCR tester, acridinorange färgning samt olika immunologiska tester för detektion av antikroppar eller antigen som till exempel enzyme-linked immunosorbent assays (ELISA) test och dipstick test. Syftet med denna studie är att utvärdera om en användning av SD Bio Line Malaria Antigen ELISA kit ger en mer känslig, tillförlitlig, praktisk samt mindre kostsam diagnostikmetod för malaria hos patienter med misstänkt malariainfektion än den nuvarande guldstandardmetoden, QBC tillsammans med blodutstryk, vid Christian Medical College and Hospital i Vellore. Patientproverna har i både ELISA testet samt QBC testet tillsammans med utstryk erhållit samma resultat vilket tyder på att SD Bio Line Malaria Antigen ELISA kitet skulle kunna vara en lika bra diagnostikmetod som QBC testet för diagnos av malaria. ELISA kitet har dock fler nackdelar, i jämförelse med QBC testet, så därför är slutsatsen att SD Bio Line Malaria Antigen ELISA kitet inte är en mer lämplig diagnostisk metod för malaria än den som används vid CMCH. Men då ELISA testet ändå ger en säker diagnos, enligt resultatet i studien, kan den vara ett lämpligt test inom något annat användningsområde.

Page generated in 0.0256 seconds