962 resultados para Anatomy of plants


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Differently graded areas of human prostate adenocarcinoma were examined after Masson's trichrome staining or immunohistochemistry for smooth muscle alpha-actin, type IV collagen and laminin. In addition, the ultrastructure of the prostatic smooth muscle cells (SMC) during glandular proliferation and epithelial invasion in selected tumors was studied. The SMC formed a thick layer below the epithelial structures in unaffected areas and were closely associated with each other in homotypic interactions. As the tumor grade increased, the SMC gradually lost interactions with each other and became atrophic. With the growth of the epithelial compartment, the SMC initially segregated to the tumor periphery and the intercellular spaces increased. In high grade tumors, the epithelial cancer cells invaded the spaces between the SMC. Immunohistochemical analysis of the basal membrane revealed increased disruption of the usually thick basal membrane, which became thinner and faintly stained with each of the antibodies used. We conclude that most SMC become atrophic following epithelial invasion in human tumors and that degradation of the basal membrane is an important factor in this process. At the ultrastructural level, different SMC phenotypes occur in prostatic tissues during epithelial invasion. Interconversion between these phenotypes is suggested and a probable relationship among them is proposed.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

BACKGROUND: We investigated, with magnetic resonance imaging, the distance of the dura mater to the spinal cord in patients without spinal or medullar disease at the 2nd, 5th, and 10th thoracic segments.METHODS: Fifty patients in the supine position underwent magnetic resonance imaging. Medial sagittal slices of the 2nd, 5th, and 10th thoracic segments were measured for the relative distances using the 1.5-T superconducting system (Gyroscan Intera, Philips Medical Systems, Best, the Netherlands). In 10 patients, the angles relative to the tangent at the insertion point on the skin were measured.RESULTS: The posterior dural-spinal cord distance is significantly greater at the midthoracic region (5th thoracic = 5.8 +/- 0.8 mm) than at the upper (2nd thoracic = 3.9 +/- 0.8 mm) and lower thoracic levels (10th thoracic = 4.1 +/- 1.0 mm) (P < 0.015). There were no differences between interspaces T2 and 110. There was no correlation between age and the measured distance between the dura mater and the spinal cord. The entry angle of the needle at T2 was 9.0 degrees +/- 2.5 degrees; at T5, 45.0 degrees +/- 7.4 degrees; and at T10, 9.50 degrees +/- 4.2 degrees.CONCLUSIONS: This study demonstrated that there is greater depth of the posterior subarachnoid space at the T2, T5, and T10 levels. The greater distance was found at T5. (Anesth Analg 2010;110:1494-5)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

is a predominant characteristic, conditioned by the presence of castes with different morphology, ontogeny, and development. The soldier caste is unique among social insects and it is responsible for colony defense. Soldiers belonging to the Nasutitermitinae subfamily are very peculiar, since they may be polymorphic and present a nasus in addition to either developed or vestigial mandibles. The defensive secretions of soldiers of the neotropical Nasutitermitinae have been the aim of several chemical studies, but few data exist concerning the anatomy and histology of the exocrine glands. This article presents a comparative study on the anatomy of the frontal gland of soldiers of several Nasutitermitinae species: Syntermes dirus (Burmeister), Syntermes nanus (Constantino), Constrictotermes cyphergaster (Silvestri), Nasutitermes corniger (Motschulsky) and Velocitermes heteropterus (Silvestri), with emphasis on the ultramorphology and ultrastructure of the frontal tube.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Styrax camporum Pohl is a shrub common in the cerrado vegetation of south-eastern Brazil. Root and stem wood in Styrax camporum differ quantitatively and qualitatively. Quantitative differences follow normal expectations: roots have wider and longer vessel elements, a lower vessel frequency, a lower ray frequency, and wider rays. Qualitative features of the roots are: simple perforation plates, vestured pits, and septate libriform fibres; qualitative features of the stems are: multiple perforation plates, non-vestured pits, and non-septate fibre-tracheids. Based on generally accepted evolutionary trends, root wood of Styrax camporum has more specialized features than stem wood. Additional comparative studies of stem and root anatomy are needed to determine if such differences between root and stem anatomy are widespread, and consistent with the lines of specialization observed in monocotyledons.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The effects of plant growth regulators GA(3) 50 mg. L-1, NAA 100 mg. L-1, CCC 1500 mg.L-1 and SADH 3000 mg.L-1 on stem anatomy of Lycopersicon esculentum Mill cv. Angela Gigante were studied. Two sets of experiments were carried out in greenhouse during two separte periods. Anatomical studies,revealed that growth promoters induced increased xylem thickness and increased the number of tracheary elements while the growth retardants decreased xylem thickness and induced fiber formation.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The floral anatomy of Eriocaulon elichrysoides Bong. and Syngonanthus caulescens (Poir.) Ruhland, from Brazilian mountain rock savannas (campos rupestres) was studied. The staminate flowers of E. elichrysoides present a diplostemonous androecium with six stamens, and those of S. caulescens present an isostemonous androecium with three stamens and three scalelike staminodes. Eriocaulon elichrysoides and S. caulescens have three nectariferous pistillodes located in the central portion of the receptacle. The pistillate flowers of E. elichrysoides present three simple styles while those of S. caulescens present three simple styles interspersed with three nectariferous appendices. Both the styles of E. elichrysoides and the nectariferous appendices of S. caulescens are vascularized by the dorsal vascular bundles of the carpels. The styles of S. caulescens lack vascularization. At the base of the gynoecium of E. elichrysoides there are six staminodes and there are three in the S. caulescens. Entomophily is suggested as the pollination syndrome in E. elichrysoides and S. caulescens as they present staminate and pistillate flowers with nectariferous structures. The ancestral character in Eriocaulon is probably given by the presence of the two staminal whorls. The staminate flowers of S. caulescens are probably derived from the reduction of a diplostemonous ancestral androecium. It remains open whether the pistillate flowers with nectariferous, appendices present an ancestral character or a derived one.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Elephant-grass is known like a great feed to dairy and beef cattle al tropical regions. Its agricultural aspects have been very observed. However, its botanical, mainly anatomical characteristics are few studied. The objective of this work was to investigate the anatomical changes occurred in stems of three elephant-grass cultivars (ROXO, EMPASC 307 TESTO and EMPASC 309 AREIA) at three stages of plant development (4, 8 and 16 weeks after sprouting). The anatomical features were similar among cultivars. When stems were young (4 weeks), a disorganization of vascular bundles were detected. However, at 8 weeks stage the were organized as a definitive form. Was observed a magnified of lignification as the stems age, mainly caused by the increased of bundles sheaths that surrounds all vascular bundles.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The gross anatomy of the portal vein (V. portae) and its tributaries was studied through anatomical methods, i.e. dissection, corrosion and diaphanization, in 45 opossums (Didelphis albiventris). In all animals the portal vein was formed by the junction of the cranial mesenteric, caudal mesenteric and lienal veins (V. mesenterica cranialis, V. mesenterica caudalis and V. lienalis, respectively). Many collateral tributaries were observed running into the portal venous trunk.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

In this study we present a survey on vegetative anatomy in species of Actinocephalus, Blastocaulon, Eriocaulon, Leiothrix, Paepalanthus, Philodice, Syngonanthus, and Tonina (Eriocaulaceae). Multivariate analyses were used to correlate anatomical characters to taxa and the habitats where the species occur. Root and stem anatomical characters seem to be more affected by environmental factors where these species occur, and seem of little value for delimiting major taxonomic groups within the family. Other characters in the leaves, such as epidermis with thickened wall cells, compartmented substomatal chambers, mesophyll with hypodermis, compact chlorenchyma, collenchymatous bundle sheath extensions, and numerous vascular bundles, were shown to be important for defining species clusters in Leiothrix, Syngonanthus, and Paepalanthus subg. Platycaulon. Similarly, loosely aggregated chlorenchyma caused Blastocaulon, Eriocaulon, Philodice, Syngonanthus sect. Carpocephalus, S. sect. Syngonanthus, and Tonina, genera from humid environments, to cluster. Scape characters appear to be more informative in discriminating groups. This situation probably reflects lower selection pressures determining anatomical characters of this organ.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Internal larval oral anatomy was used to explore morphological diversity and its contribution to the systematics of the genera Aplastodiscus, Bokerinannohyla, and Hypsiboas, belonging to the tribe Cophomantini. Internal oral morphology was examined for tadpoles of 12 species. All species have a large pair of infralabial papillae on the buccal floor and other papillae on the prelingual region. In Aplastodiscus and Bokerinannohyla, the large infralabial papillae have digitiform secondary projections. The number and arrangement of the buccal floor papillae varies among species, but they are more numerous in Aplastodiscus and Bokerinannohyla. The arrangement of the postnarial papillae is variable, but in Aplastodiscus and Bokerinannohyla, they show a definite, inverted V-shape pattern. The lateral ridge papillae are more complex in larvae of Bokertnannohyla with long digitiform secondary projections. Tadpoles of only Aplastodiscus albofrenatus, Aplastodiscus eugenioi, and Bokerinannohyla luctuosa have papillae on the buccal roof arena and larvae of all species have lateral roof papillae except Hypsiboas albomarginatus and Hypsiboas cinerascens. Larvae of Aplastodiscus, Bokermannohyla, and Hypsiboas presumably share the presence of vacuities anterior to the internal nares; although this character state is clearly synapomorphic within hylids, it is still uncertain whether it is exclusive of these three genera or whether it is present in the other genera of the tribe Cophomantini (Hyloscirtus and Myersiohyla). The inclusion of internal oral anatomy characters, such as the narial vacuities, in systematic studies is certainly valuable because it will provide additional information toward the understanding of phylogenetic relationships.