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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.
31

The pattern of anatomical connections in visual area V2 of Macaque monkey /

Abel, Paul Lawrence. January 1997 (has links)
Thesis (Ph. D.)--University of Washington, 1997. / Vita. Includes bibliographical references (leaves [81]-115).
32

Estudo morfológico e histoquímico do tubo digestivo de eleuteroembriões e larvas de Leporinus obtusidens (Valenciennes, 1836) /

Chedid, Renata Alari. January 2012 (has links)
Orientador: Carlos Alberto Vicentini / Banca: Maíra Aparecida Stefanini / Banca: Bruno Cesar Schimming / Resumo: Leporinus obtusidens apresenta características zootécnicas interessantes e promissoras para o cultivo em piscicultura. Na maioria das espécies cultivadas, as larvas, ao iniciarem a alimentação exógena, são organismos cujo desenvolvimento ainda não se completou, razão pela qual os órgãos digestivos não estão totalmente definidos e o conteúdo enzimático ainda é deficiente. As pesquisas com larvas de peixes apontam para a alimentação como o fator de maior importância a ser considerado durante o desenvolvimento inicial, pois os organismos estão na fase de diferenciação estrutural e funcional do sistema digestório. Assim o objetivo deste trabalho foi analisar as características histológicas e histoquímicas do tudo digestivo de Leporinus obtusidens nas fases iniciais do desenvolvimento. As amostras foram fixadas em solução de Karnovsky e processadas para análises histológicas e histoquímicas. A eclosão dos eleuteroembriões de L. obtusidens ocorreu às 15 horas após a fertilização (28°C) e as reservas de vitelo foram observadas até 120 horas após a eclosão (HAE). A boca sofreu modificações na posição, passando de ventral para subterminal. Com relação ao esôfago, foi possível observar as primeiras células caliciformes com 48 HAE e a partir de 64 HAE intensa positividade ao PAS e ao AB. A partir de 30 HAE foi possível observar o primórdio do estômago, caracterizado pela substituição do epitélio esofágico estratificado por epitélio gástrico simples, com presença de poucas células caliciformes. Com 96 HAE foi observada intensa reação ao PAS no epitélio de revestimento do estômago, o que indica funcionalidade do órgão. Quanto ao intestino, foi observado um desenvolvimento lento, as primeiras células caliciformes foram observadas com 96 HAE. Os cecos pilóricos foram evidenciados... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Leporinus obtusidens husbandry has characteristics very interesting and promising for cultivation in aquaculture programs. Most of the cultivated species, the larvae begin to feed exogenously, are organisms whose metamorphosis is not complete, which is why the digestive organs are not fully defined and the enzyme content is still deficient. The studies with fish larvae feeding point to as the most important factor to be considered during early development, because the organisms are in the process of structural and functional differentiation of the digestive system. Thus the objective of this study was to analyze the histological and histochemical features of digestive L. obtusidens in all stages of development. Samples were collected in the Hydrobiology and Aquaculture Station of Companhia Energetica de São Paulo (CESP) Jupiá, SP. The samples were fixed in Karnovsky solution, processed for histological and immunohistochemical analysis. The outbreak of eleuteroembryo L. obtusidens occurred approximately 15 hours after fertilization (28 ° C) and the yolk reserves were observed up to 120 HAE. The mouth has undergone successive changes during development, the ventral position to the subterminal position. With regard to the esophagus, it was possible to observe the first goblet cells with 48 HAE and and starting at 64 HAE intense positivity to PAS and AB. From 30 HAE was possible to observe the beginnings of the stomach, characterized only by the substitution of an esophageal epithelium stratified by gastric epithelium simple with cuboidal cells, with little presence of goblet cells. Was observed with 96 HAE intense reaction to PAS in the epithelium lining of the stomach, indicating functionality of the organ. As the intestine, we observed a slow development, the first goblet cells were observed... (Complete abstract click electronic access below) / Mestre
33

Myosin isoform fiber type and fiber architecture in the tail of the Virginia opossum (Didelphis virginiana)

Hazimihalis, Pano John January 2010 (has links)
No description available.
34

Histochemical studies on the pathogenesis of the elm disease incited by Ceratocystus Ulmi (buism.) C. Moreau in Ulmus Americana L.

Gagnon, Camilien Joseph Xavier. January 1965 (has links)
No description available.
35

Histology and Histochemistry of the Ovary during Oogenesis in the Autogenous Black-fly Simulium vittatum Zett.

Chen, Amy Whei-Mei 09 1900 (has links)
This research was designed to gain a better understanding of the oogenesis of the autogenous black-fly, Simulium vittatum and to compare it with studies on other Diptera. The autogenous character in S. vittatum showed only for the first gonadotropic cycle. Since the cytoblasts are first produced in the late larval period, the late larvae, early pupae, late pupae and adults of various ages were prepared separately for histological and histochemical examination. The adult female flies were fed only sugar and water. The changes in size, histology, and histochemistry of the oocyte, follicular cells and nurse-cells during oogenesis were described and the possible physiological role of these cells in oogenesis suggested. The amount and composition of larval fat-body remaining in females was compared with the stages of the oocyte development and the age of the flies. / Thesis / Master of Science (MS)
36

AN EVALUATION OF THE NEWBORN MOUSE AS A POTENTIAL MODEL FOR THE BIOASSAY OF LIVER CARCINOGENESIS USING HISTOLOGICAL AND HISTOCHEMICAL MARKERS.

Cater, Kathleen Carmelle. January 1982 (has links)
No description available.
37

Avaliação do infiltrado inflamatório do microambiente tumoral e sua relação com diferentes tipos histológicos de neoplasias mamárias caninas /

Souza, Thiago Alves de January 2017 (has links)
Orientador: Geovanni Dantas Cassali / Resumo: As neoplasias mamárias constituem os tumores com maior incidência em cadelas. Dentre os fatores que contribuem para o desenvolvimento desta e de outras neoplasias, o microambiente tumoral inflamatório desempenha um papel crucial. Vários estudos relataram papéis importantes para linfócitos, macrófagos, plasmócitos, neutrófilos, eosinófilos e mastócitos neste contexto. No presente estudo, o objetivo foi avaliar a densidade de células inflamatórias e área de fibrose tumoral e sua relação com tumores mamários caninos com diferentes características histológicas e clínicas (tumor misto benigno, carcinoma em tumor misto, carcinoma sólido e carcinoma tubular). A análise de células inflamatórias e área de fibrose tumoral foram realizadas por meio de técnicas histoquímicas, enquanto a identificação de linfócitos Tregs foram realizadas por imuno-histoquímica. A análise estatística das densidades de células inflamatórias e áreas fibrose tumoral e sua relação com os tipos histológicos revelou diferença significativa para as plasmócitos (p = 0,035), neutrófilos (p = 0,0113), macrófagos (p = 0,0047) e fibrose tumoral (p = 0,05). Os dados encontrados sugerem associações entre alto número de neutrófilos e neoplasias mamárias agressivas, entre altas densidades de plasmócitos, macrófagos e células CD8+ e entre menor densidade de células CD4+ e neoplasias menos agressivas. Maiores áreas de fibrose tumoral mostraram relação com neoplasias mamárias caninas mais agressivas. / Abstract: Mammary neoplasias constitute the tumors with higher incidence in bitches. Among the factors that contribute for the development of this and other neoplasias, the inflammatory tumor microenvironment plays a crucial role. Several studies reported important roles for lymphocytes, macrophages, plasma cells, neutrophils, eosinophils and mast cells in this context. In the present study, the goal was to evaluate density of inflammatory cells and area of tumor fibrosis and their relation with canine mammary tumors with different histologic and clinical presentation (benign mixed tumor, carcinoma in mixed tumor, solid carcinoma and tubular carcinoma) Counting and staining of inflammatory cells and tumor fibrosis were performed through histochemistry, while counting and staining of Tregs were performed through immunohistochemistry. Statistical analysis of the densities of inflammatory cells and tumor fibrosis related to histologic types revealed significant difference for plasma cells (p=0,035), neutrophils (p=0,0113), macrophages (p=0,0047), and tumor fibrosis (p=0,05). The found data suggest associations between high number of neutrophils and agressive mammary neoplasias, between high densities of plasma cells, macrophages and CD8+ cells and between low density of CD4+ cells and less aggressive neoplasias. Higher areas of tumor fibrosis showed relation with more aggressive canine mammary neoplasias. / Mestre
38

Avalia??o lectino-histoqu?mica de f?gado e linfonodo mesent?rico de b?falos mantidos em pastagens de Brachiaria spp / Lectin histochemistry evaluation of liver and mesenteric lymph node of buffaloes kept in Brachiaria spp

MIRANDA, Ileana Costa 15 December 2015 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2016-10-26T18:07:29Z No. of bitstreams: 1 2015 - Ileana Costa Miranda.pdf: 4377950 bytes, checksum: 0fd81889ff042fdd5ef81568986b1e7a (MD5) / Made available in DSpace on 2016-10-26T18:07:29Z (GMT). No. of bitstreams: 1 2015 - Ileana Costa Miranda.pdf: 4377950 bytes, checksum: 0fd81889ff042fdd5ef81568986b1e7a (MD5) Previous issue date: 2015-12-15 / CAPES / Animals grazing Brachiaria spp commonly present foamy macrophages isolated or grouped in the liver, and crystals within biliary ducts. The pathogenesis of formation and the nature of the material stored on these cells, however, are not completely known. Through lectin histochemistry evaluation, steroidal saponins (secondary glycosylated metabolites) have been identified in the crystals and within the cytoplasm of the foam cells, which are probably liable for damage the liver leading to accumulation of phylloerythrin. This study aims to standardize the use of lectin histochemistry to detect glycosylated metabolites in tissues of buffaloes kept in different Brachiaria spp pastures in Brazil. Fragments of liver and mesenteric lymph node from 40 animals were analyzed: 10 buffaloes that were kept in predominant pasture of B. decumbens for 12 months; 10 buffaloes that were kept in pasture with a predominance of B. brizantha for 18 months; 10 buffaloes that were kept in pasture of B. brizantha for approximately four years; and, as a negative control, 10 buffaloes that were maintained in native pasture without Brachiaria spp since birth. Fourteen lectins were tested (Con-A, SBA, WGA, DBA, UEA, RCA, PNA, GSL-I, PSA, LCA, PHA-E, PHA-L, SJA and SWGA), in a total of 1120 evaluated fragments. Previous studies demonstrated that PNA showed great binding reactivity for foamy macrophages in bovine and ovine. In the present study, SWGA presented high specificity and marked binding reactivity for foamy macrophages; WGA, GSL, PHA-E and PHA-L showed moderate to marked reactivity but low specificity for foamy macrophages; the other lectins didn't show significant reactivity or specificity. It remains unclear why there is this difference in lectins binding reactivity to foamy macrophages; it is suggested that divergences may occur depending on the species of Brachiaria ingested, the plant growth stage, the type and proportion of saponins stored in the plant due to seasonality, the differences in the metabolism of animal species, the presence of photosensitivity, the clinical course of the disease and the plant intake time. Moreover, there was no significant reactivity difference between the collected fragments of animals that grazed in B. decumbens for 12 months and B. brizantha for 18 months. However, the decreased presence of foamy macrophages and its lectin histochemical binding in animals that fed on B. brizantha for a longer time indicates that the animals can pass through an adaptation process according to the the plant intake time. Lectin histochemistry analysis can be used to characterize the material stored in foamy macrophages present in liver and mesenteric lymph node of buffaloes that graze in Brachiaria spp pastures and helps to clarify the pathogenesis of these cells. / Animais que se alimentam em pastos de Brachiaria spp comumente apresentam macr?fagos espumosos isolados ou agrupados no f?gado, al?m de cristais no interior de ductos biliares. A patog?nese da forma??o e a natureza do material armazenado nestas c?lulas, contudo, ainda n?o s?o completamente conhecidas. Atrav?s da avalia??o lectino-histoqu?mica, saponinas esteroidais (metab?litos glicosilados secund?rios) t?m sido identificadas nos cristais e no citoplasma das c?lulas espumosas, que provavelmente s?o respons?veis por danificar o f?gado e levar ao ac?mulo de filoeritrina. Por meio deste trabalho, objetivou-se padronizar e caracterizar a utiliza??o da lectino-histoqu?mica na detec??o de metab?litos glicosilados nos tecidos de b?falos mantidos em diferentes pastos de Brachiaria spp no Brasil. Fragmentos de f?gado e linfonodo mesent?rico de 40 animais foram analisados: 10 b?falos mantidos em pastagem predominante de B. decumbens por aproximadamente 12 meses; 10 b?falos mantidos em pastagem predominante de B. brizantha por aproximadamente 18 meses; 10 b?falos mantidos em pastagem de B. brizantha por aproximadamente quatro anos; e, como controle negativo, 10 b?falos mantidos em pastagem livre de Brachiaria spp desde o nascimento. Quatorze lectinas foram testadas (Con-A, SBA, WGA, DBA, UEA, RCA, PNA, GSL-I, PSA, LCA, PHA-E, PHA-L, SJA e SWGA), em um total de 1120 fragmentos avaliados. Estudos anteriores demonstraram que a lectina PNA possui marcada reatividade para macr?fagos espumosos de bovinos e ovinos. No presente estudo, a lectina SWGA apresentou acentuada reatividade e alta especificidade para macr?fagos espumosos; WGA, GSL, PHA-E e PHA-L mostraram moderada a acentuada reatividade, mas baixa especificidade aos macr?fagos espumosos; as outras lectinas n?o apresentaram reatividade ou especificidade significativas. Ainda n?o se sabe exatamente a que atribuir a diferen?a de reatividade aos macr?fagos espumosos. Sugere-se que diverg?ncias ocorram em fun??o da esp?cie de Brachiaria ingerida, da fase de crescimento da planta, do tipo e propor??o dos glicoconjugados armazenados na planta em decorr?ncia da ?poca do ano, das diferen?as no metabolismo da esp?cie do animal em quest?o, da presen?a de fotossensibiliza??o, da evolu??o cl?nica da doen?a e do tempo de ingest?o da planta. N?o houve diferen?a de marca??o significativa entre os fragmentos coletados de animais que se alimentaram de B. decumbens por 12 meses e B. brizantha por 18 meses. Por?m, a diminui??o da presen?a e marca??o lectino-histoqu?mica dos macr?fagos espumosos nos tecidos dos b?falos que ingeriram B. brizantha durante mais tempo indica que os animais podem passar por um processo de adapta??o de acordo com o tempo de ingest?o da planta. A avalia??o lectino-histoqu?mica pode ser utilizada para caracterizar o material armazenado em macr?fagos espumosos presentes no f?gado e linfonodo mesent?rico de b?falos que se alimentam em pastagens de Brachiaria spp e ajuda na compreens?o da patog?nese de forma??o destas c?lulas.
39

Immunohistochemical fiber typing, ultrastructure, and morphometry of harbor seal skeletal muscle

Watson, Rebecca Reiko 30 September 2004 (has links)
There is strong evidence that the skeletal muscles of pinnipeds are adapted for an aerobic, lipid-based metabolism under the hypoxic conditions associated with breath-hold diving. However, regional variations in mitochondrial density are unknown, and the few fiber typing studies performed on pinniped skeletal muscles are not consistent with an aerobic physiological profile. Thus, the objectives of this study were to (1) reexamine the fiber type distribution throughout the primary locomotory muscles of the harbor seal, and (2) to better understand the density and distribution of mitochondria in the locomotory muscles. Multiple samples from transverse sections of the epaxial muscles and a single sample of the pectoralis muscle of wild harbor seals were analyzed using immunohistochemical fiber typing and electron microscopy. Fiber typing results indicated that harbor seal epaxial muscles are composed of 47.4% type I (slow twitch, oxidative) fibers and 52.8%, IIa (fast twitch, oxidative) fibers. No fast twitch, glycolytic (type IIb) fibers were detected in the epaxial muscles or the pectoralis muscle. Mean volume density of mitochondria [Vv(mt,f)] was 5.6%, which is elevated over what would be predicted for a terrestrial mammal of similar mass. The elevated Vv(mt,f) had a high proportion of intermyofibrillar mitochondria, a trait not normally found in the muscles of terrestrial mammals with elevated Vv(mt,f). These results provide further evidence that the elevated mitochondrial volume density in pinniped muscle decreases the oxygen diffusion distance between myoglobin and mitochondria to facilitate aerobic respiration in working muscles. In addition, analyses of heterogeneity revealed that the regions of the epaxial muscles that were located deep within the muscle showed a significantly higher Vv(mt,f) relative to those regions that were superficially-located. In contrast, there was no significant heterogeneity of fiber type detected in either plane of the epaxial muscles. Thus, there was a fine-scale pattern of spatial heterogeneity of Vv(mt,f) within the epaxial muscles that does not manifest in fiber type distribution, indicating that the fibers have similar oxidative capacities.
40

Immunohistochemical fiber typing, ultrastructure, and morphometry of harbor seal skeletal muscle

Watson, Rebecca Reiko 30 September 2004 (has links)
There is strong evidence that the skeletal muscles of pinnipeds are adapted for an aerobic, lipid-based metabolism under the hypoxic conditions associated with breath-hold diving. However, regional variations in mitochondrial density are unknown, and the few fiber typing studies performed on pinniped skeletal muscles are not consistent with an aerobic physiological profile. Thus, the objectives of this study were to (1) reexamine the fiber type distribution throughout the primary locomotory muscles of the harbor seal, and (2) to better understand the density and distribution of mitochondria in the locomotory muscles. Multiple samples from transverse sections of the epaxial muscles and a single sample of the pectoralis muscle of wild harbor seals were analyzed using immunohistochemical fiber typing and electron microscopy. Fiber typing results indicated that harbor seal epaxial muscles are composed of 47.4% type I (slow twitch, oxidative) fibers and 52.8%, IIa (fast twitch, oxidative) fibers. No fast twitch, glycolytic (type IIb) fibers were detected in the epaxial muscles or the pectoralis muscle. Mean volume density of mitochondria [Vv(mt,f)] was 5.6%, which is elevated over what would be predicted for a terrestrial mammal of similar mass. The elevated Vv(mt,f) had a high proportion of intermyofibrillar mitochondria, a trait not normally found in the muscles of terrestrial mammals with elevated Vv(mt,f). These results provide further evidence that the elevated mitochondrial volume density in pinniped muscle decreases the oxygen diffusion distance between myoglobin and mitochondria to facilitate aerobic respiration in working muscles. In addition, analyses of heterogeneity revealed that the regions of the epaxial muscles that were located deep within the muscle showed a significantly higher Vv(mt,f) relative to those regions that were superficially-located. In contrast, there was no significant heterogeneity of fiber type detected in either plane of the epaxial muscles. Thus, there was a fine-scale pattern of spatial heterogeneity of Vv(mt,f) within the epaxial muscles that does not manifest in fiber type distribution, indicating that the fibers have similar oxidative capacities.

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