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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.
321

Aspects of host-parasite interaction in laboratory populations of insects

Rogers, David John January 1970 (has links)
No description available.
322

EVALUATION OF EFFICICACY OF CURCUMIN ON OPPORTUNISTIC BACTERIA, INFLAMMATION, AND PARASITES IN THE GASTROINTESTINAL TRACT OF WORKING HORSES

Wuest, Samantha 01 December 2016 (has links)
Twelve working horses were utilized in a completely randomized design to examine the efficacy of curcumin as an anti-parasitic, anti-inflammatory, and anti-microbial. Horses were randomly assigned to either the control (CON) containing no curcumin or to the curcumin (CUR) treatment which was dosed at 15 g of 500 mg/g of 95% curcumin per day (n = 6/treatment). Fecal samples were collected on day 0 before initiation of treatments and then daily for 30 days. Feces from working horses were evaluated for shedding of Streptococcus bovis/ equinus complex, Clostridium difficile, and Clostridium perfringens. Inflammation was observed through erythrocyte sedimentation rate (ESR) via jugular venipuncture every 3-4 days. Horses were fed treatments at 1100 daily and samples were collected prior to administration of treatments. Dosing curcumin at the recommended rate of 15 g per horse had no effect (P ≥ 0.58) on total fecal egg count, strongyles, or ascarids. There was a day effect (P ≤ 0.05) with parasite shedding mimicking the parasites life cycle. Treatment had no effect on ESR (P ≤ 0.42); however, a day effect (P ≤ 0.001) was observed with the CUR horses with ESR decreasing (P = 0.0006) on d 14 and d 21 compared to d 0. There was no treatment (P = 0.34) or day effect (P = 0.53) on concentration of Clostridium perfringens. Similarly, there was no treatment effect for Clostridium difficile (P = 0.51) or SBEC (P = 0.69). Day had an effect (P = 0.0001) on Clostridium difficile, for both CON and CUR horses with all horses having higher concentrations on d 0 and d 1 compared to all other days. Concentrations of SBEC were affected by day (P = 0.05) with concentrations increasing on different days for both CON and CUR horses. Data would suggest that curcumin has a potential benefit as an anti-inflammatory for working horses starting at d 14 when being dosed at 15 g of 500 mg/g of 95% curcumin. This dosage for 30 days however had no additional benefits as an anti-parasitic and anti-microbial. Curcumin has a potentially negative effect on the GIT by increasing opportunistic bacteria and more research is needed to further evaluate the anti-microbial and anti-parasitic effects of curcumin in horses.
323

The reproductive ecology of a northeastern Pacific nudibranch, Janolus fuscus, with an examination of its endoparasitic copepod, Ismaila belciki

Wolf, Maya, 1981- 12 1900 (has links)
xxii, 242 p. : ill. (some col.) / The arminacean nudibranch Janolus fuscus (family Zephyrinidae) is found in rocky intertidal habitats along the northeast Pacific coast. Adult J. fuscus are conspicuous from April to October but absent in the early winter at two sites, North Cove and Fossil Pt., in the Coos Bay region of Oregon. Over four years of intertidal surveys at these sites, the density of J. fuscus peaked with the abundance of their bryozoan prey, Bugula pacifica and Tricellaria circumternata , in spring and summer, while adult absence in winter was correlated with strong winter storms. To describe the timing of development and determine the life cycle of J. fuscus , embryos and larvae were reared in the laboratory and examined with light, scanning electron, and confocal microscopy. Larvae reared in the lab and juveniles collected from the field were monitored to quantify growth. Janolus fuscus exhibited typical spiral cleavage and hatched as planktotrophic veligers that grew for over a month before they reached competency, settled, and metamorphosed on their prey, B. pacifica . Juvenile growth was rapid, and adults reached maximum sizes of over 50 mm before dying. These demographic and developmental studies suggest that J. fuscus is a subannual species with a life span of approximately five months. Janolus fuscus is often infected with an endoparasitic copepod, Ismaila belciki . In the field, prevalence of I. belciki increased with host density and size. The distribution of I. belciki was weakly aggregated in the host population. The large female parasite was generally found in the anterior portion of the host hemocoel, and one or more dwarf males were typically associated with each female. Infected J. fuscus produced significantly smaller egg masses with fewer larvae than did uninfected individuals. Infection did not influence growth rate but did cause decreased survival in older nudibranchs. To examine the life cycle of I. belciki , naupliar larvae were reared in the lab and incubated with potential hosts. Additionally, copepodid stages were described from dissected J. fuscus collected from the field. Ismaila belciki has a least three planktotrophic naupliar stages and four copepodid stages in its life cycle. / Committee in charge: Barbara Roy, Chairperson; Craig Young, Advisor; Richard Emlet, Member; Sandra Brooke, Member; Frances White, Outside Member
324

A role for differential host resistance to the hemiparasitic angiosperm, Rhinanthus minor L. in determining the structure of host plant communities?

Cameron, Duncan Drummond January 2004 (has links)
This study describes the effect of the root hemi-parasitic angiosperm Rhinanthus minor on the structure of the communities in which it lives and seeks to elucidate a mechanism through which the parasite acts to effect these changes in the community. Field manipulations reveal that R. minor suppressed the growth of grasses and legumes in a newly sown meadow whilst promoting the forbs within one growing season. In contrast the removal of R. minor from mature meadow plots did not influence their composition. After an additional growing season the parasite did not further influence the composition of the new meadows but removal did begin to benefit the biomass of mature plots. In isolation the parasite caused most damage to grasses whilst leaving legumes and forbs undamaged. Moreover, the parasite performed worst in terms of growth and photosynthesis when attached to the forbs. Consequently the parasite was able to moderate intra-specific competition between grasses and forbs. I thus hypothesised that forbs were able to prevent the parasite form abstracting resources where as grasses could not. Tracer experiments using isotopically e5N) labelled potassium nitrate confirmed this hypothesis showing that more of the resources taken up by the host were stolen by the parasite from grasses than from forbs. There was much variability in the translocation of resources from the legume studied. The reasons underlying the differential uptake of resources were highlighted using histological studies which showed that all of the forbs possessed successful resistance mechanisms to the parasite whilst no successful resistance was observed in the grasses or legumes. Two different resistance mechanisms were observed in the forbs; hypersensitive cell-death at the host-parasite interface and host lignification. I therefore propose that differential host resistance may underlie this parasite's community level effects as forbs possess a resistance capacity that other potential hosts do not.
325

Střevní paraziti obratlovců na Svalbardu / Intestinal parasites of vertebrates in Svalbard

MYŠKOVÁ, Eva January 2014 (has links)
The study was aimed to obtain basic information about the distribution of intestinal parasites of mammals and birds in Svalbard. Faeces of different species were used to detect intestinal parasites. All samples were collected during two seasons and examined by microscopic methods and molecular diagnostic was used for detection of microsporidia, cryptosporidia, coccidia and giardiae.
326

Parazitofauna plazů Evropy / Parasitofauna of Reptiles of Europe

ŽÍDEK, Jakub January 2014 (has links)
This thesis presents the most comprehensive historical overwiev of reptile parasites living in Europe, including basic taxonomic information, the known geographic range, host range and important references. Data needed to create a host-parasite list was obtained from scientific articles. In the present work are recorded parasites of the Eropean reptiles throughout their entire range. Moreover was created a comprehensive list of the European herpetofauna that were still incomplete, including threat status and endemic species.
327

Caracterização de cepas de Strongyloides stercoralis (Bavay, 1876) Stiles & Hassal, 1902 (Rhabditida, Strongyloididae) isoladas de pacientes com e sem sintomatologia da região de Araraquara-SP

Miné, Júlio César [UNESP] 25 November 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:33:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-11-25Bitstream added on 2014-06-13T18:07:29Z : No. of bitstreams: 1 mine_jc_dr_arafcf.pdf: 1238485 bytes, checksum: c0cab12233278cce39285c34cc901f95 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A estrongiloidíase é uma doença parasitária que tem distribuição mundial heterogênea, cuja prevalência é dividida em três categorias: esporádica (<1%), endêmica (1-5%) e hiperendêmica (>5%). Na região de Araraquara, estudos de frequência de enteroparasitoses vêm sendo conduzidos desde 1970 e mostram que a estrongiloidíase é endêmica na região. Com o intuito de realizar caracterização morfométrica de diferentes isolados humanos desse helminto, provenientes dos municípios de Araraquara, Américo Brasiliense, Gavião Peixoto, Motuca e Rincão foi feita a mensuração de larvas rabditóides e filarióides e sequenciamento da região ITS-1 do rDNA das larvas filarióides. Com o auxilio do programa de captura e mensuração de imagens Motic Images Advanced 3.2., os parâmetros das larvas rabditóides e filarióides propostos por TEIXEIRA, 1996, foram mensurados após fixação das mesmas em TAF. A extração do DNA genômico foi realizada segundo protocolo descrito por NILFOROUSHAN et al., 2007 e em seguida realizou-se a amplificação do ITS-1 por meio de NESTED-PCR. Os fragmentos de aproximadamente 680 pb obtidos foram purificados, sequenciados e a comparação de sequências foi realizada pelo programa ClustalW. Apenas com os resultados da análise morfométrica, não foi possível caracterizar diferentes cepas de S. stercoralis, uma vez que... / Strongyloidiasis is a parasitic disease that occurs worldwide heterogeneous, whose prevalence is divided into three categories: sporadic (<1%), endemic (1-5%) and hyperendemic (> 5%). In the region of Araraquara, studies the frequency of intestinal parasites have been conducted since 1970 and show that strongyloidiasis is endemic in the region. In order to perform morphometric characterization of different isolates of human intestinal worms, from the municipalities of Araraquara, Américo Brasiliense, Gavião Peixoto, Motuca and Rincão the measurement was made of rhabditiforms and filariforms larvae and sequencing of the ITS-1 rDNA filariform larvae. With the help of the program capture and measurement of images Motic Images Advanced 3.2., the rhabditiforms and filariforms larvae parameters proposed by TEIXEIRA, 1997, were measured after fixed on the TAF. The extraction of genomic DNA was performed according to protocol described by NILFOROUSHAN et al., 2007 and then held the amplification of ITS-1 by nested-PCR. Fragments of about 680 bp obtained were purified, sequenced and the sequence comparison was performed by the program ClustalW. Only the results of the morphometric analysis was not possible to characterize different S. stercoralis strains, since the values of the parameters measured were quite homogeneous in larvae... (Complete abstract click electronic access below)
328

Evolution of Multigene Families and Single Copy Genes in Plasmodium spp.

January 2016 (has links)
abstract: The complex life cycle and widespread range of infection of Plasmodium parasites, the causal agent of malaria in humans, makes them the perfect organism for the study of various evolutionary mechanisms. In particular, multigene families are considered one of the main sources for genome adaptability and innovation. Within Plasmodium, numerous species- and clade-specific multigene families have major functions in the development and maintenance of infection. Nonetheless, while the evolutionary mechanisms predominant on many species- and clade-specific multigene families have been previously studied, there are far less studies dedicated to analyzing genus common multigene families (GCMFs). I studied the patterns of natural selection and recombination in 90 GCMFs with diverse numbers of gene gain/loss events. I found that the majority of GCMFs are formed by duplications events that predate speciation of mammal Plasmodium species, with many paralogs being neutrally maintained thereafter. In general, multigene families involved in immune evasion and host cell invasion commonly showed signs of positive selection and species-specific gain/loss events; particularly, on Plasmodium species is the simian and rodent clades. A particular multigene family: the merozoite surface protein-7 (msp7) family, is found in all Plasmodium species and has functions related to the erythrocyte invasion. Within Plasmodium vivax, differences in the number of paralogs in this multigene family has been previously explained, at least in part, as potential adaptations to the human host. To investigate this I studied msp7 orthologs in closely related non-human primate parasites where homology was evident. I also estimated paralogs’ evolutionary history and genetic polymorphism. The emerging patterns where compared with those of Plasmodium falciparum. I found that the evolution of the msp7 multigene family is consistent with a Birth-and-Death model where duplications, pseudogenization and gene lost events are common. In order to study additional aspects in the evolution of Plasmodium, I evaluated the trends of long term and short term evolution and the putative effects of vertebrate- host’s immune pressure of gametocytes across various Plasmodium species. Gametocytes, represent the only sexual stage within the Plasmodium life cycle, and are also the transition stages from the vertebrate to the mosquito vector. I found that, while male and female gametocytes showed different levels of immunogenicity, signs of positive selection were not entirely related to the location and presence of immune epitope regions. Overall, these studies further highlight the complex evolutionary patterns observed in Plasmodium. / Dissertation/Thesis / Doctoral Dissertation Biology 2016
329

Atividade endectocida de uma nova alternativa terapêutica (S-cifenotrina, Butóxido de piperonila, D-tetrametrina e Ivermectina) em cães /

Mendonça, Rafael Paranhos de. January 2007 (has links)
Orientador: Alvimar José da Costa / Banca: Gilson Pereira de Oliveira / Banca: Luciano Melo de Souza / Resumo: Utilizando-se de delineamentos experimentais apropriados, foi avaliada a atividade endectocida de uma nova associação medicamentosa, composta de dois piretróides (Scifenotrina e D-tetrametrina), butóxido de piperonila e ivermectina. Quatro experimentos foram conduzidos para avaliação terapêutica da nova associação, comparativamente à formulações adquiridas no mercado. Para avaliação carrapaticida e pulicida foram conduzidos dois experimentos. No primeiro ensaio, 21 cães naturalmente infestados por Rhipicephalus sanguineus, selecionados por meio de duas contagens consecutivas, foram randomizados e sorteados em três grupos de sete animais cada. No segundo ensaio, 21 cães selecionados foram randomizados e sorteados, também, em três grupos de sete animais cada. Infestações artificiais foram realizadas nos dias -4, -2, 6, 13, 20, 27 e 34 com Ctenocephalides felis felis (100 pulgas) e nos dias -1, 6, 13, 20, 27 e 34 com R. sanguineus (30 carrapatos). Nos dois experimentos a nova formulação foi comparada à associação D-fenotrina 78,125%+ piriproxifen 2,575%. A eficácia sarnicida da nova formulação experimental, comparativamente à selamectina 12%, foi avaliada em 15 cães naturalmente infestados por S. scabiei var. canis. Raspados cutâneos e avaliações clínicas (regressão das lesões de pele) foram realizados, em todos os cães experimentais. Para avaliação anti-helmíntica, 24 cães foram selecionados por meio de exames coprológicos e distribuídos em três grupos de oito animais cada. As contagens de ovos de nematódeos por grama de fezes (OPG) foram realizadas nos dias -3, -2, -1 (seleção dos animais) e 1, 3, 7, 10 e 14 pós-tratamento. A nova formulação experimental foi comparada à Selamectina 12%.Todos os dados foram avaliados estatisticamente, e as inferências devidamente extraídas...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Utilizing of the appropriate experimental design, was evaluated the anti-parasite activity of a new formulation, composed of two piretroids (S-cifenotrin and D-tetrametrin), piperonil butox and ivermectinn. Four experiments had been lead for therapeutical evaluation of the new association, comparativily to the formulation acquired in the market. For the evaluation against ticks and flea, two experiments had been lead. In the first assay, 21 dogs naturally infested by Rhipicephalus sanguineus, selected by means of two consecutive countings, were shuffted and randomly put into three groups of seven animals each. In the second assay, 21 selected dogs were allocated randomly, also, in three groups of seven animals each. Artificial infestations had been carried through in days -4, -2, 6, 13, 20, 27 and 34 with Ctenocephalides felis felis (100 fleas) and in days -1, 6, 13, 20, 27 and 34 with R. sanguineus (30 ticks). In the two experiments the new formulation was compared with the association D-fenotrin 78.125%+ piriproxifen 2.575%. The scabies’ effectiveness of the new experimental formulation, comparativily to selamectin 12%, was evaluated in 15 dogs naturally infested by S. scabiei var. canis. Cutaneous scrapings and clinical evaluations (regression of the skin injuries) had been carried through, in all the experimental dogs. For antihelmintic evaluation, 24 dogs had been selected by means of the coprology examinations and distributed in three groups of eight animals each. The egg countings of nematodes for gram of fezes (EPG) had been carried through in days -3, -2, -1 (election of the animals) and 1, 3, 7, 10 and 14 post-treatment. The new experimental formulation was compared with the selamectina 12%...(Complete abstract, acess undermentioned eletronic address) / Mestre
330

Atividade endectocida de uma nova alternativa terapêutica (S-cifenotrina, Butóxido de piperonila, D-tetrametrina e Ivermectina) em cães

Mendonça, Rafael Paranhos de [UNESP] 29 January 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:57Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-01-29Bitstream added on 2014-06-13T20:57:21Z : No. of bitstreams: 1 mendonca_rp_me_jabo.pdf: 999544 bytes, checksum: 24d985deb1f2b8c0000be6982d5c9e3f (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Utilizando-se de delineamentos experimentais apropriados, foi avaliada a atividade endectocida de uma nova associação medicamentosa, composta de dois piretróides (Scifenotrina e D-tetrametrina), butóxido de piperonila e ivermectina. Quatro experimentos foram conduzidos para avaliação terapêutica da nova associação, comparativamente à formulações adquiridas no mercado. Para avaliação carrapaticida e pulicida foram conduzidos dois experimentos. No primeiro ensaio, 21 cães naturalmente infestados por Rhipicephalus sanguineus, selecionados por meio de duas contagens consecutivas, foram randomizados e sorteados em três grupos de sete animais cada. No segundo ensaio, 21 cães selecionados foram randomizados e sorteados, também, em três grupos de sete animais cada. Infestações artificiais foram realizadas nos dias -4, -2, 6, 13, 20, 27 e 34 com Ctenocephalides felis felis (100 pulgas) e nos dias -1, 6, 13, 20, 27 e 34 com R. sanguineus (30 carrapatos). Nos dois experimentos a nova formulação foi comparada à associação D-fenotrina 78,125%+ piriproxifen 2,575%. A eficácia sarnicida da nova formulação experimental, comparativamente à selamectina 12%, foi avaliada em 15 cães naturalmente infestados por S. scabiei var. canis. Raspados cutâneos e avaliações clínicas (regressão das lesões de pele) foram realizados, em todos os cães experimentais. Para avaliação anti-helmíntica, 24 cães foram selecionados por meio de exames coprológicos e distribuídos em três grupos de oito animais cada. As contagens de ovos de nematódeos por grama de fezes (OPG) foram realizadas nos dias -3, -2, -1 (seleção dos animais) e 1, 3, 7, 10 e 14 pós-tratamento. A nova formulação experimental foi comparada à Selamectina 12%.Todos os dados foram avaliados estatisticamente, e as inferências devidamente extraídas... / Utilizing of the appropriate experimental design, was evaluated the anti-parasite activity of a new formulation, composed of two piretroids (S-cifenotrin and D-tetrametrin), piperonil butox and ivermectinn. Four experiments had been lead for therapeutical evaluation of the new association, comparativily to the formulation acquired in the market. For the evaluation against ticks and flea, two experiments had been lead. In the first assay, 21 dogs naturally infested by Rhipicephalus sanguineus, selected by means of two consecutive countings, were shuffted and randomly put into three groups of seven animals each. In the second assay, 21 selected dogs were allocated randomly, also, in three groups of seven animals each. Artificial infestations had been carried through in days -4, -2, 6, 13, 20, 27 and 34 with Ctenocephalides felis felis (100 fleas) and in days -1, 6, 13, 20, 27 and 34 with R. sanguineus (30 ticks). In the two experiments the new formulation was compared with the association D-fenotrin 78.125%+ piriproxifen 2.575%. The scabies effectiveness of the new experimental formulation, comparativily to selamectin 12%, was evaluated in 15 dogs naturally infested by S. scabiei var. canis. Cutaneous scrapings and clinical evaluations (regression of the skin injuries) had been carried through, in all the experimental dogs. For antihelmintic evaluation, 24 dogs had been selected by means of the coprology examinations and distributed in three groups of eight animals each. The egg countings of nematodes for gram of fezes (EPG) had been carried through in days -3, -2, -1 (election of the animals) and 1, 3, 7, 10 and 14 post-treatment. The new experimental formulation was compared with the selamectina 12%...(Complete abstract, acess undermentioned eletronic address)

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