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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.
211

Part I¡GCharacterization of humoral immune responses of mice infected with Angiostrongylus cantonensis Part II¡GAnalysis on the cranial morphology of mice infected with Angiostrongylus cantonensis

Yang, Zhi-Ya 10 September 2002 (has links)
Abstract -1 The immune response occurred in the mice infected with Angiostrongylus cantonensis was mainly humoral immune response. This study was designed to compare the systemic and localized humoral immune responses occurred after primary and secondary infections in C57BL/6J mice. Eight weeks after the primary infection with 20 third-stage larvae, each mouse received a second inoculation of the same dosage. Specific serum IgM, IgG and IgE were found in the second week after primary infection. However, the titers of IgG1 and IgG2b increased at the fourth week after primary infection. Antibodies of these mentioned increased continuously as the progress of infection. On the other hand, the IgM and IgG1 titers increased in brain tissue infusion since the forth week after primary infection, while the titer of IgG start to elevate at the sixth week. Nevertheless, the increase of IgG2B was only noticed at the sixth week and no significant change was observed for IgG2a and IgE. After the secondary infection, serum IgM titers increased while the titer of IgG1 in the brain tissue infusion decreased. Results of Western blot showed that IgG1and IgE in the brain tissue infusion lost the ability to recognize a 42 kDa molecule of the somatic and excreting-secreting antigens of fifth-stage larvae. These variations could be used in the diagnosis of the early stage of mice that re-infected with Angiostrongylus cantonensis. Abstract -2 The radiographic lateral views of the skulls of the mice infected with Angiostrongylus cantonensis were taken. Thus, the parietofrontal index ( PI ) was obtained by measuring and calculating the distances among specific positions on their skulls. Compared with the controls, a significant elevation over the top of the crania of the cases was observed sixty days post-infection. In addition, the phenomenon emerged apparently during the second to the fourth week post-infection. These findings are able to be applied as the external diagnostic references for the infection course of mice infected with Angiostrongylus cantonensis.
212

Effective antigen presentation and survival requirements for tumor-specific CD8+ T cells in vivo /

Markiewicz, Mary A. M. January 2001 (has links)
Thesis (Ph. D.)--University of Chicago, Committy on immunology, June 2001. / Includes bibliographical references. Also available on the Internet.
213

Studies of the regulatory function of L2a in mouse CD8 gene expression

Yao, Xin 28 August 2008 (has links)
Not available
214

A comparison between humoral and cellular immune responses following measles vaccination in two different settings /

Bautista-López, Norma Leticia. January 2000 (has links)
Despite the use of measles vaccine for over 30 years, measles continues to occur even in highly vaccinated populations. The goal set by the Pan American Health Organization to eliminate measles from the Americas has not been accomplished yet. Although live-measles attenuated vaccines have dramatically reduced the incidence of measles infection, relatively little is known about the immune response generated by vaccination. The principal objective of the work described in this thesis was to perform detailed analysis of cellular and humoral responses to primary measles vaccination in children from the developed and developing worlds. Studies involving Canadian children ranging in age from 12 months to 15 years of age demonstrated that cellular "memory" for measles antigens (lymphoproliferation) was induced in only 50--60% of vaccinees but that, in some children, this cellular response was more durable than anti measles antibody production. Phenotypic studies in these children demonstrated an evolution of early CD8+ T cell activation with later CD4+ T cell activation over a 5--8 week period after vaccination. Expression of CD30, a putative Th2 marker and the costimulatory molecule CTLA-4 on CD4+ and CD8+ T cells, was associated with a strong humoral response while increased production of IFN-gamma and IL-12 was associated with a strong LP response to vaccination. Similar, though less extensive, studies in Peru revealed that less than 25% of these developing world children mount detectable measles-specific LP responses after vaccination, despite having high antibody titers. Although there are many differences between the two study populations (e.g.: race, age at vaccination, vaccine strain), one especially striking difference was the relative "maturity" of T cells in Peruvian children (CD45RO expression) and the marked degree of PBMC activation at the time of vaccination in this setting.
215

Effects of Delivery Mode on Initial Infant Gut Colonization And Subsequent Immune System Development

Kang, Christina 01 January 2014 (has links)
Since the 1970s, the United States has encountered an increasing proportion of Cesarean deliveries (CS), surpassing the advised 10-15% maximum rate established in 1985 by the World Health Organization (World Health Organization, 1985). This increasing rate has fueled correlational and causational studies observing the impact of Cesarean delivery on several aspects of infant health. Previous studies on CS infants have observed a delay in gut colonization by beneficial bacteria – for instance Bifidobacteria – traditionally transmitted from the mother’s gut and vaginal microbiome as other environmental factors have influenced the initial microflora (Biasucci et al., 2010; Dong, Yang, & Wang, 2010; Penders et al., 2006). In addition, an increasing proportion of births are occurring within a home setting, providing an opportunity to study how these possible environmental factors may influence bacterial colonization. This initial gastrointestinal colonization is considered one of the most important factors towards immune system development and general health. This thesis proposes an examination of how the mode and setting of delivery influence the diversity of Bifidobacterium species in infants’ initial gut microbiomes. Additionally, while several studies have examined the impact of specific bacterial species on immune system development, this study will provide an approach to understanding how differences in the overall gastrointestinal (GI) ecologies of CS and vaginal delivery (VD) infants impact immune system development.
216

Immunocompetence in young and old laying hens in response to dietary folic acid and Escherichia coli lipopolysaccharide challenge

Munyaka, Peris Mumbi 06 September 2012 (has links)
We investigated the effects of dietary folic acid and age, on immunological parameters in laying hens challenged with LPS. 48 Shaver White hens at different ages were fed 2 wheat-soybean based diets with 0 or 4 mg supplemental FA per kg of diet for 8 wk. 6 hens from each dietary treatment were injected with 8 mg/kg body weight of LPS or saline and observed for 4 h. A few diet X challenge interaction were observed in young hens, whereas FA and LPS independently influenced a number of parameters. In older hens, there were very few diet X challenge interactions as well as effects of FA, whereas LPS affected several parameters. In conclusion, dietary FA influenced some immune responses in younger hens, but no such effects were observed in older hens. FA may modulate immune responses in laying hens under acute LPS challenge which could be tissue and age dependent.
217

The influence of physical activity on cytokine production in healthy older males

Jankord, Ryan D. January 2002 (has links)
The purpose of this study was to examine the influence of physical activity on cytokine production in healthy older males. Twelve males (six very active, six less active) ages 65 to 74 were recruited for this study. Blood was obtained at rest and serum concentrations for MIP-I a, IL-1 ra, IL-6 and IL-10 were measured. No difference was found in MIP-la and IL-Ira concentrations between the two groups. The serum concentration of IL-6 was significantly lower (p = 0.016) in the very active group compared to the less active group. The very active group had a significantly higher (p = 0.016) concentration of IL-10 compared to the less active group. The beneficial influence of physical activity on cytokine production is clinically important because of the role of IL-6 and IL-10 in disease development in older adults. Through influencing cytokine concentrations, our results provide further insights into the role of physical activity in attenuating the effects of aging. / School of Physical Education
218

Host induced microevolution of ESX secretion systems of M. Tuberculosis.

Sukkhu, Melisha. January 2013 (has links)
The ESX family of genes (esxA-W) in Mycobacterium tuberculosis (Mtb) encodes 23 effector molecules influencing immunogenicity and pathogenicity. This study was aimed at identifying and evaluating variations in ESX sequence and protein expression profiles in clinical isolates and examining how diversity might influence immune responses. 23 ESX genes from 55 clinical isolates (20 Beijing, 25 KZN and 10 Other) and 3 Laboratory strains (H37Rv, H37Ra and BCG) were sequenced. 482 single nucleotide polymorphisms (SNPs) were identified in 12 ESX genes relative to H37Rv. Majority of the identified 363 nsSNPs occured in Beijing isolates. No mutations were observed in esxA, B, C, E, G, H, J, R, S and T. Six unique nsSNPs were identified in the Beijing isolates: esxI (Q20L), esxO (E52G), 2 in esxP (T3S; N83D), esxU (P63S) and esxW (T2A). Three unique nsSNPs were identified in the KZN isolates: esxK (A58T), esxL (R33S). The esxL polymorphism resulted from a dinucleotide change. ESX gene transcription levels were evaluated using RT-qPCR. Varying expression levels were observed for esxA, B, C, F, M and Q across all clinical isolates with lowest levels seen amongst the Beijing isolates. This correlated with immunoblots with confirmed decreased esxAB protein expression relative to the other strains. The Matrix-Assisted Laser Desorption Ionization Time of Flight (MALDI-TOF) spectral protein profiles were quantitatively compared within and between Mtb clinical and laboratory isolates. Protein spectral profiles within the mass range of the CFP-10 protein with variations in peak intensities were observed across all isolates. QILSS and Mtb9.9 peptides were tested individually for immune responses in TB infected patients. Healthy patients displayed no responses to QILSS and Mtb9.9, strong but variable immune responses were detected for specific regions of QILSS and Mtb9.9 in TB infected patients. These findings demonstrate that differences in sequence, transcriptional profiles and protein expression patterns in ESX secreted proteins exist between clinical isolates, and may translate into differences in human immune responses. Further research is needed to correlate human host immune responses to the phenotype and genotype of the infecting strain of Mtb to determine the consequences of specific variations of the other ESX members. These studies are important for the development of improved immune diagnostics and vaccines. / Thesis (Ph.D.)-University of University of Natal, Durban, 2013.
219

Immunocompetence in young and old laying hens in response to dietary folic acid and Escherichia coli lipopolysaccharide challenge

Munyaka, Peris Mumbi 06 September 2012 (has links)
We investigated the effects of dietary folic acid and age, on immunological parameters in laying hens challenged with LPS. 48 Shaver White hens at different ages were fed 2 wheat-soybean based diets with 0 or 4 mg supplemental FA per kg of diet for 8 wk. 6 hens from each dietary treatment were injected with 8 mg/kg body weight of LPS or saline and observed for 4 h. A few diet X challenge interaction were observed in young hens, whereas FA and LPS independently influenced a number of parameters. In older hens, there were very few diet X challenge interactions as well as effects of FA, whereas LPS affected several parameters. In conclusion, dietary FA influenced some immune responses in younger hens, but no such effects were observed in older hens. FA may modulate immune responses in laying hens under acute LPS challenge which could be tissue and age dependent.
220

Immunomodulatory activity of murine keratinocyte-derived exosomes

Kotzerke, Kristina 20 January 2015 (has links)
No description available.

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