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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

Unsteady Aerodynamics of Rotorcraft at Low Advance Ratios in Ground Effect

Ganesh, Balakrishnan 05 April 2006 (has links)
The aerodynamic characteristics of rotorcraft flying at low speed close to the ground are investigated. This will help better understand and quantify the flowfield structures and unsteadiness associated with various in ground effect flight conditions. This study aims to separate out the various phenomena according to their causal factors. Experimental investigations first involved flow visualization, which helped in identifying the various flight regimes and in getting an approximate estimate of the unsteadiness. The problem was divided into its unsteady and quasi-steady aspects. Hotwire measurements were performed and the unsteadiness in the flow structure was quantified. It was found that there were long time scale and fluctuations in the upwind side of the rotor disk, with significant changes in the in and flow. On the quasi-steady side, the fuselage loads for two fuselage cross-sectional shapes were investigated both in and out of ground effect. The fuselage cross-section shape had a significant effect on the loads felt by the fuselage in ground effect. The power required for the experimental configuration was measured to provide a basis for comparison. Finally, the flowfield around the ground vortex was quantified, and the structure of the ground vortex was investigated using Particle Image Velocimetry. It was found that tip vorticity was ingested by the ground vortex and that the strength of the ground vortex was considerably more than the tip vortex.
2

IgE para ácaros, barata e Ascaris lumbricoides: impacto na IgE total e implicações para o desenvolvimento de alergia e asma / IgE to mites, cockroach and Ascaris lumbricoides: impact on total IgE and implications for the development of allergy and asthma

Palhas, Priscila Botelho 17 May 2018 (has links)
A imunoglobulina E (IgE) tem papel central na patogênese das doenças alérgicas. É parte da resposta do tipo 2, e as citocinas IL-4 e IL-13 são essenciais para que haja produção deste isotipo de imunoglobulina. Produção de IgE é também induzida por parasitas intestinais, particularmente helmintos. O objetivo do presente estudo foi avaliar a contribuição de IgE específica para ácaros, barata, gato, cachorro e para o parasita Ascaris lumbricoides sobre os níveis de IgE total entre crianças de áreas distintas no Brasil. Anticorpos IgE para ácaros Dermatophagoides pteronyssinus e Blomia tropicalis; barata Blattella germanica; gato; cachorro; e A. lumbricoides foram medidos usando o sistema ImmunoCAP, e comparados à IgE total no soro de 150 crianças de 3-6 anos de idade vivendo na cidade de Natal, endêmica para parasitoses intestinais, e de 54 crianças de 3-6 anos de idade com asma e/ou rinite, vivendo em Ribeirão Preto. Níveis de IgE total foram significantemente mais elevados em crianças de Natal quando comparados aqueles em crianças de Ribeirão Preto (média geométrica 630,9 kU/L, faixa 19,6-63.290 kU/L; e 398,1 kU/L, faixa 35,7-4.803 kU/L, respectivamente). Entre as 150 crianças de Natal, 52(34,6%) apresentaram IgE positiva para D.pteronyssinus; 70(46,6%) para B.tropicalis; 45(30%) para barata; 19(12,6%) para gato; 17(11,3%) para cachorro; e 125(83,3%) para A.lumbricoides. Entre as 54 crianças com asma e/ou rinite de Ribeirão Preto, 41(75,9%) apresentaram IgE positiva para D.pteronyssinus; 34(62,9%) para B.tropicalis; 22(40,7%) para barata; 11(20,3%) para gato; 12(22,2%) para cachorro. Embora estas crianças fossem negativas para parasitas à inclusão no estudo, 22(40,7%) tinham IgE para A.lumbricoides. Anticorpos IgE para A. lumbricoides foram mais elevados entre crianças de Natal, quando comparados a IgE para alérgenos inalantes (p<0,01). Níveis de IgE para D. pteronyssinus entre crianças de Ribeirão Preto foram mais altos que IgE para outros inalantes e A.lumbricoides (p<0,01). Em Natal, a porcentagem de IgE para A. lumbricoides em relação à IgE total foi maior em comparação a IgE para D.pteronyssinus e B.germanica (mediana 0,41%; 0,08%; e 0,04% respectivamente, p<0,01). Em Ribeirão Preto, a porcentagem de IgE para D.pteronyssinus e para B.tropicalis em relação à IgE total foi maiorem comparação a IgE para A.lumbricoides e barata (mediana 9,8%; 0,6%; 0,3%; e 0,2%, respectivamente, p<0,05). Regressão linear revelou que a associação mais forte foi para IgE para A.lumbricoides com IgE total em Natal (R²=0,56; p<0,01); associação significante foi também observada para IgE para ácaros com IgE total em Ribeirão Preto (R2=0,35; p<0,01 para D.pteronyssinus; R2=0,33; p<0,01 para B.tropicalis, respectivamente). Nossos resultados demonstraram que anticorpos IgE para ácaros contribuem fortemente para a IgE total entre crianças com asma e/ou rinite, vivendo em uma área de baixa taxa de infecções parasitárias em nosso meio. Por outro lado, entre crianças vivendo em uma área em que parasitas são encontrados em abundância, infecções parasitárias induzem uma forte resposta IgE policlonal, e anticorpos IgE específicos para parasita, além de ácaros, barata, gato e cachorro representam uma modesta proporção da IgE total. A especificidade desta IgE, e os efeitos a longo prazo desta resposta cedo na vida, permanecem desconhecidos. / Immunoglobulin E (IgE) plays a central role in the pathogenesis of allergic diseases. It is part of the type 2 response, and the cytokines IL-4 and IL-13 are essential for the production of this immunoglobulin isotype. IgE production is also induced by intestinal parasites, particularly helminths. The aim of the present study was to evaluate the contribution of specific IgE to mites, cockroach, cat, dog and parasite Ascaris lumbricoides on total IgE levels among children living in different areas in Brazil. IgE antibodies to mites Dermatophagoides pteronyssinus and Blomia tropicalis; cockroach Blattella germanica; cat; dog; and A. lumbricoides were measured using the ImmunoCAP system and compared to total serum IgE of 150 children 3-6 year-old living in the city of Natal, endemic for intestinal parasites, and 54 children 3-6 years of age with asthma and /or rhinitis, living in Ribeirão Preto. Total IgE levels were significantly higher in children from Natal as compared to those among children in Ribeirão Preto (geometric mean 630,9 kU/L, range 19,6-63.290 kU/L; e 398,1 kU/L, range 35,7-4.803 kU/L, respectively). Among the 150 children from Natal, 52(34.6%) presented IgE positive to D.pteronyssinus; 70(46.6%) to B. tropicalis; 45(30%) to cockroach; 19 (12.6%) to cat; 17(11.3%) to dog; and 125(83.3%) to A. lumbricoides. Among the 54 children with asthma and /or rhinitis from Ribeirão Preto, 41(75.9%) had IgE positive to D.pteronyssinus; 34(62.9%) to B.tropicalis; 22(40.7%) to cockroach; 11(20.3%) to cat; 12(22.2%) to dog. Although these children were negative for parasites at inclusion in the study, 22(40.7%) had IgE to A.lumbricoides. IgE antibodies to A.lumbricoides were higher among children from Natal, as compared to IgE to inhalant allergens (p<0.01). IgE levels to D.pteronyssinus among children living in Ribeirão Preto were higher than IgE to other inhalants and A.lumbricoides (p<0.01). In Natal, the percentage of IgE to A.lumbricoides in relation to total IgE was higher in comparison to IgE to D.pteronyssinus e B.germanica (median 0.41%, 0.08%, and 0.04% respectively, p<0.01). In Ribeirão Preto, the percentage of IgE to D.pteronyssinus and to B.tropicalis in relation to total IgE was higher in comparison to IgE to A.lumbricoides and cockroach (median 9.8%, 0,6%, 0.3%, and 0.2%, respectively, p <0.05). Linear regression analysis revealed that the strongest association was for IgE to A.lumbricoides with total IgE in Natal (R²=0.56, p<0.01); significantassociation was also observed for IgE to mites with total IgE in Ribeirão Preto (R2=0.35, p<0.01 for D. pteronyssinus, R2=0.33, p<0.01 for B.tropicalis, respectively). Our results demonstrated that IgE antibodies to mites contribute strongly to total IgE among children with asthma and /or rhinitis, living in an area of low parasite infection rates in our country. On the contrary, among children living in an area where parasites are found in abundance, parasitic infections induce a strong polyclonal IgE response, and IgE antibodies specific for parasite, and also for mites, cockroaches, cat and dog represent a modest proportion of total IgE. The specificity of these IgE antibodies and the implications of this response occurring early in life remain unknown.
3

Analyses of IgE response appeared in different body fluid of mice infected with Angiostrongylus cantonensis

Cheng, Po-Ching 27 June 2001 (has links)
The IgE response increased in hosts infected with Angiostrongylus cantonensis. This study analyzes IgE responses appeared in different body fluids of mice infected with A. cantonensis. BALB/c, CBA, C57BL/6 and C57BL/10 strain of mice were used in the experiment. BALB/c mice exhibited the highest susceptibility to A. cantonensis, CBA mice showed intermediate susceptibility, while C57BL/6 and C57BL/10 mice showed the lowest susceptibility. Analyses of specific antibodies against L5 antigens, and ES antigens in mice showed antibodies appeared in sera and in cerebrospinal fluids(CSF), especially IgE antibodies, were related to the worm rejection happened in mouse brain. However, antibodies appeared in ascites had no influence. The level of IgE increased in brain of susceptible BALB/c mice is much lower than that increased in other strain. Our data suggested that IgE response elicited in brain might be much more important than that in serum. Western blot analyses showed that among antigens extracted from L5 both IgE and IgG responses were positive in CSF. IgE antibodies against a 105 kDa protein of L5 antigen in C57BL/10 mice appeared in third week after infection, while in BALB/c mice appeared in fifth week. IgG antibodies against 105 kDa protein appeared in the identical weeks. Our results indicated that 105 kDa protein was related to specific antibodies responses about protective function of mice infected with A. cantonensis. Further researches will be required to understand function and characterization of this protein.
4

CD23's role as a negative regulator of allergic disease : in vivo effects of murine CD23 destabilization and allelic mutations /

Ford, Jill Wallace, January 2007 (has links)
Thesis (Ph. D.)--Virginia Commonwealth University, 2007. / Prepared for: Dept. of Microbiology and Immunology. Bibliography: leaves 233-255. Also available online via the Internet.
5

IgE para ácaros, barata e Ascaris lumbricoides: impacto na IgE total e implicações para o desenvolvimento de alergia e asma / IgE to mites, cockroach and Ascaris lumbricoides: impact on total IgE and implications for the development of allergy and asthma

Priscila Botelho Palhas 17 May 2018 (has links)
A imunoglobulina E (IgE) tem papel central na patogênese das doenças alérgicas. É parte da resposta do tipo 2, e as citocinas IL-4 e IL-13 são essenciais para que haja produção deste isotipo de imunoglobulina. Produção de IgE é também induzida por parasitas intestinais, particularmente helmintos. O objetivo do presente estudo foi avaliar a contribuição de IgE específica para ácaros, barata, gato, cachorro e para o parasita Ascaris lumbricoides sobre os níveis de IgE total entre crianças de áreas distintas no Brasil. Anticorpos IgE para ácaros Dermatophagoides pteronyssinus e Blomia tropicalis; barata Blattella germanica; gato; cachorro; e A. lumbricoides foram medidos usando o sistema ImmunoCAP, e comparados à IgE total no soro de 150 crianças de 3-6 anos de idade vivendo na cidade de Natal, endêmica para parasitoses intestinais, e de 54 crianças de 3-6 anos de idade com asma e/ou rinite, vivendo em Ribeirão Preto. Níveis de IgE total foram significantemente mais elevados em crianças de Natal quando comparados aqueles em crianças de Ribeirão Preto (média geométrica 630,9 kU/L, faixa 19,6-63.290 kU/L; e 398,1 kU/L, faixa 35,7-4.803 kU/L, respectivamente). Entre as 150 crianças de Natal, 52(34,6%) apresentaram IgE positiva para D.pteronyssinus; 70(46,6%) para B.tropicalis; 45(30%) para barata; 19(12,6%) para gato; 17(11,3%) para cachorro; e 125(83,3%) para A.lumbricoides. Entre as 54 crianças com asma e/ou rinite de Ribeirão Preto, 41(75,9%) apresentaram IgE positiva para D.pteronyssinus; 34(62,9%) para B.tropicalis; 22(40,7%) para barata; 11(20,3%) para gato; 12(22,2%) para cachorro. Embora estas crianças fossem negativas para parasitas à inclusão no estudo, 22(40,7%) tinham IgE para A.lumbricoides. Anticorpos IgE para A. lumbricoides foram mais elevados entre crianças de Natal, quando comparados a IgE para alérgenos inalantes (p<0,01). Níveis de IgE para D. pteronyssinus entre crianças de Ribeirão Preto foram mais altos que IgE para outros inalantes e A.lumbricoides (p<0,01). Em Natal, a porcentagem de IgE para A. lumbricoides em relação à IgE total foi maior em comparação a IgE para D.pteronyssinus e B.germanica (mediana 0,41%; 0,08%; e 0,04% respectivamente, p<0,01). Em Ribeirão Preto, a porcentagem de IgE para D.pteronyssinus e para B.tropicalis em relação à IgE total foi maiorem comparação a IgE para A.lumbricoides e barata (mediana 9,8%; 0,6%; 0,3%; e 0,2%, respectivamente, p<0,05). Regressão linear revelou que a associação mais forte foi para IgE para A.lumbricoides com IgE total em Natal (R²=0,56; p<0,01); associação significante foi também observada para IgE para ácaros com IgE total em Ribeirão Preto (R2=0,35; p<0,01 para D.pteronyssinus; R2=0,33; p<0,01 para B.tropicalis, respectivamente). Nossos resultados demonstraram que anticorpos IgE para ácaros contribuem fortemente para a IgE total entre crianças com asma e/ou rinite, vivendo em uma área de baixa taxa de infecções parasitárias em nosso meio. Por outro lado, entre crianças vivendo em uma área em que parasitas são encontrados em abundância, infecções parasitárias induzem uma forte resposta IgE policlonal, e anticorpos IgE específicos para parasita, além de ácaros, barata, gato e cachorro representam uma modesta proporção da IgE total. A especificidade desta IgE, e os efeitos a longo prazo desta resposta cedo na vida, permanecem desconhecidos. / Immunoglobulin E (IgE) plays a central role in the pathogenesis of allergic diseases. It is part of the type 2 response, and the cytokines IL-4 and IL-13 are essential for the production of this immunoglobulin isotype. IgE production is also induced by intestinal parasites, particularly helminths. The aim of the present study was to evaluate the contribution of specific IgE to mites, cockroach, cat, dog and parasite Ascaris lumbricoides on total IgE levels among children living in different areas in Brazil. IgE antibodies to mites Dermatophagoides pteronyssinus and Blomia tropicalis; cockroach Blattella germanica; cat; dog; and A. lumbricoides were measured using the ImmunoCAP system and compared to total serum IgE of 150 children 3-6 year-old living in the city of Natal, endemic for intestinal parasites, and 54 children 3-6 years of age with asthma and /or rhinitis, living in Ribeirão Preto. Total IgE levels were significantly higher in children from Natal as compared to those among children in Ribeirão Preto (geometric mean 630,9 kU/L, range 19,6-63.290 kU/L; e 398,1 kU/L, range 35,7-4.803 kU/L, respectively). Among the 150 children from Natal, 52(34.6%) presented IgE positive to D.pteronyssinus; 70(46.6%) to B. tropicalis; 45(30%) to cockroach; 19 (12.6%) to cat; 17(11.3%) to dog; and 125(83.3%) to A. lumbricoides. Among the 54 children with asthma and /or rhinitis from Ribeirão Preto, 41(75.9%) had IgE positive to D.pteronyssinus; 34(62.9%) to B.tropicalis; 22(40.7%) to cockroach; 11(20.3%) to cat; 12(22.2%) to dog. Although these children were negative for parasites at inclusion in the study, 22(40.7%) had IgE to A.lumbricoides. IgE antibodies to A.lumbricoides were higher among children from Natal, as compared to IgE to inhalant allergens (p<0.01). IgE levels to D.pteronyssinus among children living in Ribeirão Preto were higher than IgE to other inhalants and A.lumbricoides (p<0.01). In Natal, the percentage of IgE to A.lumbricoides in relation to total IgE was higher in comparison to IgE to D.pteronyssinus e B.germanica (median 0.41%, 0.08%, and 0.04% respectively, p<0.01). In Ribeirão Preto, the percentage of IgE to D.pteronyssinus and to B.tropicalis in relation to total IgE was higher in comparison to IgE to A.lumbricoides and cockroach (median 9.8%, 0,6%, 0.3%, and 0.2%, respectively, p <0.05). Linear regression analysis revealed that the strongest association was for IgE to A.lumbricoides with total IgE in Natal (R²=0.56, p<0.01); significantassociation was also observed for IgE to mites with total IgE in Ribeirão Preto (R2=0.35, p<0.01 for D. pteronyssinus, R2=0.33, p<0.01 for B.tropicalis, respectively). Our results demonstrated that IgE antibodies to mites contribute strongly to total IgE among children with asthma and /or rhinitis, living in an area of low parasite infection rates in our country. On the contrary, among children living in an area where parasites are found in abundance, parasitic infections induce a strong polyclonal IgE response, and IgE antibodies specific for parasite, and also for mites, cockroaches, cat and dog represent a modest proportion of total IgE. The specificity of these IgE antibodies and the implications of this response occurring early in life remain unknown.
6

The Responsiveness of Rabbit Bronchial Rings to Antigen, AGEPC and Histamine

Smith, Peter F., Palmer, John D., Holmes, Todd, Cutcher, Ann, Dunn, Anita M., Halonen, Marilyn 01 January 1986 (has links)
Rings of intrapulmonary bronchi isolated from rabbits producing anti-horseradish peroxidase IgE antibodies contracted when exposed to antigen. The contractile response had a lag period of about 1 min, reached a peak at 6 min and then subsided. Bronchi from rabbits with detectable levels of specific IgG (in addition to IgE) antibodies did not differ in response from those with undetectable specific IgG levels. Histamine also contracted rabbit intrapulmonary bronchi with an EC50 of 10ωM (SD 1.29). The response to antigen was completely inhibited with chlorpheniramine (30 ωM). In contrast to intrapulmonary bronchi, responsiveness of mainstem bronchi to antigen was observed only occasionally, whereas histamine was equipotent on both mainstem and intrapulmonary bronchi. Thus, the amount of antigen-induced mediator release may be less in the mainstem bronchi. Acetyl glyceryl ether phosphorylcholine, in concentrations up to 10 ωM, did not contract either mainstem or intrapulmonary bronchi. This study indicates that histamine is the major mediator of (and acetyl glyceryl ether phosphorylcholine does not significantly participate in) antigen-induced contraction of isolated bronchi from IgE-producing rabbits. The results provide a likely mechanism for the increase in pulmonary resistance observed in IgE anaphylaxis in this species.
7

Šunų I tipo padidinto jautrumo reakcijos klinikinė ir laboratorinė diagnostika / Clinical and laboratory diagnosis of type I hypersensitivity reaction in dogs

Liaudanskaitė, Urtė 05 March 2014 (has links)
Šunų I tipo padidinto jautrumo reakcijos klinikinė ir laboratorinė diagnostika. Darbo apimtis 42 puslapiai, sudarytos 8 lentelės, 6 paveikslai, naudoti 62 literatūros šaltiniai. Darbo tikslas - klinikiniais ir laboratoriniais tyrimo metodais įvertinti I tipo alerginės reakcijos atvejus šunų tarpe, kurie pasitaiko nedidelės smulkių gyvūnų klinikos praktikoje. Tyrimas buvo atliekamas veterinarijos klinikoje „Pas pumą“ 2012 – 2013 m. Buvo užregistruoti 38 šunų susirgimai, susiję su I tipo padidinto jautrumo reakcijos klikiniais požymiais, iš savininkų surinkta išsami anamnezė ir atlikti hematologiniai (morfologija) tyrimai. Imunologiniam tyrimui surinkti 13 alergiškų ir 12 sveikų šunų kraujo serumo mėginiai. Imunologinis IFA (ELISA) tyrimas, nustatyti tiriamųjų šunų IgE koncentracijai kraujo serume, buvo atliktas Lietuvos sveikatos mokslų universiteto veterinarijos fakulteto anatomijos ir fiziologijos katedros imunologijos laboratorijoje. Tyrimo metu nustatyta, kad dažniausiai pasitaikanti I tipo padidinto jautrumo reakcijos forma šunų tarpe buvo atopinis dermatitas (63,2 proc.), kurios ryškiausias požymis buvo niežulys (57,9 proc.), daugiausiai apimantis ausis ir pilvo ventralinę sieną. Šunų lytis ir veislė neturėjo reikšmingos įtakos I tipo padidinto jautrumo reakcijos pasireiškimui, o amžiaus tendencija ryški – alergijos pirmieji požymiai pasireiškia 6 mėn. – 2 m. šunims (62,5 – 78,57 proc.), o šunims iki 6 metų amžiaus alergijos pasikartoja dažniau. Kraujo neutrofilų... [toliau žr. visą tekstą] / Master thesis: Clinical and laboratory diagnosis of type I hypersensitivity reaction in dogs. Master thesis volume 41 pages, consisting of 8 tables, 6 pictures, 61 references used. The main aim of the thesis is to evaluate type I hypersensitivity reaction cases in dogs in small animal veterinary practice using clinical and laboratory methods. The study was carried out in veterinary practise “Pas pumą” in 2012 – 2013. 38 cases of dogs associated with type I hypersensitivity reaction were registered and a detailed medical history was collected from these dogs owners. Haematological examination was performed. Blood samples were collected from 13 dogs with type I hypersensitivity and from 12 healthy dogs. Immunological test ELISA was done to evaluate canine serum IgE levels concentration. Testing was performed in Lithuanian University of Health Sciences , Faculty of Veterinary Anatomy and Physiology, Department of Immunology laboratory. The analysis of clinical findings has shown the most common type I hypersensitivity clinical presentation among dogs is atopic dermatitis (63.2 percent). The most common clinical features were pruritus (57.9 percent) mainly of the ears and the ventral abdominal wall. Dog gender and breed had no significant effect on type I hypersensitivity reactions. The analysis showed that first signs of allergy for dogs commonly occur from 6 months until 2 years of age (62.5 – 78.57 percent of dogs). Allergies had a higher incidence of recurrence in dogs up... [to full text]
8

Cytokin mRNA profil i perifera mononukleära celler hos barn med födoämnesallergi / Profiling of cytokine mRNA in peripheral mononuclear cells in children with food allergy.

Strzelczyk, Barbara January 2011 (has links)
No description available.
9

Risk factors for impaired lung function in the elderly

Villar, M. Tracey A. January 1995 (has links)
No description available.
10

IgE Enhances B Cell-Derived Exosomal Induced T Cell Proliferation

Keith, Brooks 30 November 2012 (has links)
For many years it has been known that the injection of antigen bound to an antibody leads to more than a 1000-fold increase in antigen specific antibody response. This observation holds true for IgE, which is dependent upon CD23 expression, as this enhancement is not present in mice deficient in CD23. It also has been shown that when mice are injected with IgE-antigen complexes also display an increase in antigen specific T cell proliferation. While there are published studies that demonstrate a role for B cell derived exosomes in the activation and proliferation of T cells, none have focused upon the potential role of CD23 as a molecular basis for this phenomenon, at least in the context of allergy and asthma. This thesis provides direct evidence that B cell-derived exosomes possess co-stimulatory molecules, including CD80 and CD86, which act in concert with CD23 to induce T cell proliferation, at least in vitro. This is due to, or enhanced by, the exosomal transfer of the antigen or peptide to T cells. Importantly, the antigen transfer is dependent upon the availability of IgE and the expression of CD23.

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