984 resultados para veia coccígea dorsal


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Adults of Pseudopolydora rosebelae sp. nov. inhabit silty tubes on muddy bottoms in shallow water in southern Brazil, states of Sao Paulo and Rio de Janeiro. They are rare and extremely delicate, attaining 20 mm long for 55 chaetigers. The worms are distinctive by their colourful yellow and black pigmentation on the anterior part of body and palps, prominent transverse hood on the dorsal anterior edge of chaetiger 3, and lack of coloured respiratory pigment in blood. Of 12 examined individuals, all were females. Oogenesis is intraovarian; oocytes develop from chaetigers 14-15 to chaetigers 24-36. Recently laid oocytes were about 150 mu m in diameter, with embryos and developing larvae found in capsules inside female tubes in March-June. Broods comprised up to 23 capsules with 400 propagules. Capsules were joined to each other in a string and each attached by a single thin stalk to the inner wall of the tube. Larvae hatched at the 4-chaetiger stage and fed on plankton. Pelagic larvae are unique among Pseudopolydora in having large ramified mid-dorsal melanophores from chaetiger 3 onwards. Competent larvae are able to settle and metamorphose at the 15-chaetiger stage, but can remain planktonic up to 18 chaetigers. They have one pair of unpigmented ocelli and three pairs of black eyes in the prostomium, unpaired ramified mid-dorsal melanophores on chaetiger 1 and on the pygidium, ramified lateral melanophores on chaetigers 5-10, prominent yellow chromatophores in the prostomium, peristomium, on dorsal and ventral sides of chaetigers and in the pygidium. Branchiae are present on chaetigers 7-10, and gastrotrochs are arranged on chaetigers 3, 5, 7 and 12. Provisional serrated bristles are present in all notopodia, and hooks are present in neuropodia from chaetiger 8 onwards. Two pairs of provisional protonephridia are present in chaetigers 1 and 2, and adult metanephridia are present from chaetiger 4.

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Linepithema humile Mayr is an ant species originally native to South America that has been spread accidently throughout the globe through international trade. It is a serious urban and crop pest. Despite its economic importance, little is known about the larvae of this species apart from a brief description based on a few specimens. The present investigation is aimed at describing every immature stage of L. humile. Three larval instars were determined through the frequency distribution of the maximum width of head capsules from a sample of 525 larvae. The morphological descriptions were based on 150 eggs, 70 larvae, and 90 pupae examined by light and scanning electron microscopy. Some morphological characteristics reported to be typical of Linepithema Mayr larvae were confirmed - dolichoderoid body shape, presence of dorsal protuberance, sparse simple body hairs, presence of nine pairs of spiracles and dolichoderoid mandibles. We concluded that an earlier published description was based on queen larvae, and that the protuberance is only present in worker larvae. The information provided in this study may aid ant systematics and phylogenetics, as well provide a better understanding of the biology of this species.

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Linepithema micans Forel is a poorly studied species that is now considered a pest in vineyards in South Brazil. Larval characters have been used in a few phylogenetic studies, and their importance greatly depends in the amount of available information on different species. This study presents a complete panorama on the external morphology of the immatures of L. micans based on observations by light and scanning electron microscopy. The number of larval instars was estimated as three based on the frequency distribution of head widths of 965 larvae. Larvae of L. micans were similar to other Linepithema Mayr in the general format of body and mandibles, presenting a dorsal abdominal protuberance, nine pairs of spiracle, and unbranched hairs. On the other hand, L. micans was unique for having shorter hairs, predominantly denticulate, intraspecific variation in the number of antennal sensilla and in the types of sensilla on the labial palps were reported. Microsc. Res. Tech. 74:337-342, 2011. (C) 2010 Wiley-Liss, Inc.

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Eusarcus Perty 1833 is one of the oldest described genera of Pachylinae, comprising 36 species distributed from northeastern to southern Brazil (including the central west region), northeastern Argentina, eastern Paraguay and Uruguay. The genus is reviewed and a new classification is proposed based on a cladistic analysis. A cladistic analysis was performed with the 34 valid species of Eusarcus and 11 species belonging to certain Gonyleptidae subfamilies. The data matrix has 67 characters: 14 from dorsal scutum and pedipalp, 38 from male legs and 15 from male genitalia. Two equally parsimonious trees were found (L=319; C. I.=0.26, R. I.=0.61). Pygophalangodus gemignanii uruguayensis Ringuelet 1955a and Pygophalangodus gemignanii gemignanii Mello-Leitao 1931b are here elevated to the category of species, and the following new combinations are proposed: E. catharinensis (Mello-Leitao 1927); E. berlae (Mello-Leitao 1932); E. gemignanii (Mello-Leitao 1931b); E. signatus(Roewer 1949); E. sooretamae (Soares & Soares 1946a); E. uruguayensis (Ringuelet 1955a). The following generic synonymies are proposed: Eusarcus Perty 1833 (type species E. armatus Perty 1833) = Metagraphinotus Mello-Leitao 1927 (type species M. catharinensis Mello-Leitao 1927), Pareusarcus Roewer 1929 (type species P. corniculatus Roewer 1929), Pygophalangodus Mello-Leitao 1931b (type species P. gemignanii-gemignanii Mello-Leitao 1931b) and Antetriceras Roewer 1949 (type species A. signatus Roewer 1949). The following specific synonymies are proposed: Eusarcus hastatus Sorensen 1884 = Pucrolioides argentina Roewer 1913, E. guimaraensi H. Soares 1945, Jacarepaguana pectinifemur Piza 1943, Canestrinia canalsi Mello-Leitao 1931a, and E. maquinensis H. Soares 1966b; E. armatus Perty 1833 = E. curvispinosus Mello-Leitao 1923b, and Enantiocentron montis Mello-Leitao 1936; Eusarcus catharinensis (Mello-Leitao 1927) = E. antoninae Mello-Leitao 1936, E. perpusillus Mello-Leitao 1945, E. tripos Mello-Leitao 1940, and Metagraphinotus trochanterspinosus Soares & Soares 1947b; E. nigrimaculatus Mello-Leitao 1924 = Pareusarcus centromelos Mello-Leitao 1935a, E. furcatus Roewer 1929, Orguesia armata Roewer 1913, and Pareusarcus corniculatus Roewer 1929; E. oxyacanthus Kollar in Koch 1839a = Enantiocentron doriphorus Mello-Leitao 1932, and E. spinimanu Mello-Leitao 1932; E. pusillus Sorensen 1884 = E. vervloeti B. Soares 1944c; E. berlae Mello-Leitao 1932 = Metagraphinotus arlei Mello-Leitao 1935a. Metapucrolia armata (Sorensen 1895) is revalidated, transferred to Eusarcus and considered as a species inquirenda. A new name, Eusarcus metapucrolia is proposed for this species to avoid homonymy with the type species of Eusarcus, E. armatus Perty 1833. Eusarcus aberrans Mello-Leitao 1939a is considered as a species inquirenda. The male of E. teresincola Soares & Soares 1946a is described. Female of the following species are described: E. bifidus Roewer 1929; E. dubius B. Soares 1943b; E. insperatus B. Soares 1944a; E. schubarti Soares & Soares 1946a; E. sooretamae (Soares & Soares 1946a). The following new species are described from Brazil: E. acrophthalmus (type locality: Bahia, Ilheus, Parataquice); E. alpinus (Rio de Janeiro, Santa Maria Madalena, Parque Estadual do Desengano); E. caparaoensis (Minas Gerais, Alto Caparao, Parque Nacional do Caparao); E. cavernicola (Goias, Sao Domingos, Parque Estadual de Terra Ronca, Lapa da Angelica); E. didactylus (Rio de Janeiro, Teresopolis, Parque Nacional Serra dos Orgaos); E. garibaldiae (Santa Catarina, Itajai); E. geometricus (Rio de Janeiro, Teresopolis, Parque Nacional Serra dos Orgaos); E. manero (Rio de Janeiro, Marica, Itaipuacu); E. matogrossensis (Mato Grosso, Chapada dos Guimaraes); E. mirabilis (Minas Gerais, Marlieria, Parque Estadual Rio Doce); E. sergipanus (Sergipe, Itabaiana, Parque Nacional de Itabaiana) and E. tripectinatus (Minas Gerais, Rio Preto). The holotype of E. curvispinosus is proposed as the neotype of E. armatus Perty 1833, the type material of which has been lost. Lectotypes for the following species were designated: E. aduncus; E. hastatus; E. oxyacanthus.

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A new species of Geoplaninae land planarian from south Peru, Gigantea urubambensis sp. nov., is described. The most outstanding features of the new species are the very dorsal location of the testes, between the dorsal diagonal and the supra-intestinal parenchymatic muscle layers; a penis papilla projecting from the roof of the male atrium and acentrally traversed by the ejaculatory duct; and the absence of glandular ridges on the penis papilla.

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In this paper we present the description of five new species of tetranychid mites collected in south Tunisian oasis areas. These are: Bryobia alveolata sp. nov., Aplonobia crispipilis sp. nov., Petrobia (Petrobia) carthagensis sp. nov., Petrobia (Petrobia) pseudotetranychina sp. nov. and Tetranychus (Tetranychus) atriplexi sp. nov. The notion of dorsal tubercles used to separate the sub-genera Tetranychina from Petrobia sensu stricto and Mesotetranychus among the genus Petrobia is also discussed.

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BACKGROUND: A dichloromethane-methanol extract of the seeds of Piper tuberculatum Jacq. (Piperaceae) and two isobutyl amides, 4,5-dihydropiperlonguminine (1) and pellitorine (2), which were isolated by chromatographic methods, were assayed for their lethality against the sugarcane borer Diatraea saccharalis F. (Lepidoptera: Pyralidae). RESULTS: Bioassays were carried out with fourth-instar caterpillars through topical application of test solutions to the dorsal surface of the prothorax, and dose-response correlations were determined. Significant insect mortalities were observed 24, 48 and 72 h after treatment at concentrations of >= 100 mu g insect(-1). The LD(50) and LD(90) values for compound 1 were 92.83 and 176.50 mu g insect(-1), and for compound 2 they were 91.19 and 184.56 mu g insect(-1). CONCLUSION: According to the LD(50) and LD(90) for compounds 1 and 2, it can be inferred that the values reflect an acute lethal response to both compounds, based on interaction(s) of the toxicants with a primary target or series of targets. Thus, the amides were demonstrated to have potential value in the control of the sugarcane borer. (C) 2008 Society of Chemical Industry

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In this work the effects of topic use of Brazilian green propolis gel in the contraction of wounds performed in rat`s skin was evaluated. In ten female Wistar rats were done four wounds in dorsal region. Two wounds in each rat were treated daily with Brazilian green propolis gel during 10 days. The wounds were photographed daily, and the images were analyzed with ImageJ software, in order to measure wound areas and evaluate wound contraction. In the graphic analysis, treated group and control group had similar behavior, and both evolved for complete closure in 10th experimentation day. The wound clots fell down before in treated wounds. Green propolis in the gel formulation at 5% in topical use had not effect in the process of wound contraction. The macroscopic visualization of the contraction of wounds, by itself, does not seem to be a good indicator of the process of tissue repair.

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Simultaneous measurements of pulmonary blood flow (qPA), coeliacomesenteric blood flow (qCoA), dorsal aortic blood pressure (PDA), heart rate (fH) and branchial ventilation frequency (fv) were made in the Australian lungfish, /Neoceratodus forsteri, /during air breathing and aquatic hypoxia. The cho­linergic and adrenergic influences on the cardiovascular system were investigated during normoxia using pharmacological agents, and the presence of catecholamines and serotonin in different tissues was investi­gated using histochemistry. Air breathing rarely occurred during normoxia but when it did, it was always associated with increased pulmonary blood flow. The pulmonary vasculature is influenced by both a cho­linergic and adrenergic tonus whereas the coeliacomesenteric vasculature is influenced by a β-adrenergic vasodilator mechanism. No adrenergic nerve fibers could be demonstrated in /Neoceratodus /but catecholamine-containing endothelial cells were found in the atrium of the heart. In addition, serotonin-­immunoreactive cells were demonstrated in the pulmonary epithelium. The most prominent response to aquatic hypoxia was an increase in gill breathing frequency followed by an increased number of air breaths together with increased pulmonary blood flow. It is clear from the present investigation that /Neoceratodus /is able to match cardiovascular performance to meet the changes in respiration during hypoxia.

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Although it has long been supposed that resistance training causes adaptive changes in the CNS, the sites and nature of these adaptations have not previously been identified. In order to determine whether the neural adaptations to resistance training occur to a greater extent at cortical or subcortical sites in the CNS, we compared the effects of resistance training on the electromyographic (EMG) responses to transcranial magnetic (TMS) and electrical (TES) stimulation. Motor evoked potentials (MEPs) were recorded from the first dorsal interosseous muscle of 16 individuals before and after 4 weeks of resistance training for the index finger abductors (n = 8), or training involving finger abduction-adduction without external resistance (n = 8). TMS was delivered at rest at intensities from 5 % below the passive threshold to the maximal output of the stimulator. TMS and TES were also delivered at the active threshold intensity while the participants exerted torques ranging from 5 to 60 % of their maximum voluntary contraction (MVC) torque. The average latency of MEPs elicited by TES was significantly shorter than that of TMS MEPs (TES latency = 21.5 ± 1.4 ms; TMS latency = 23.4 ± 1.4 ms; P < 0.05), which indicates that the site of activation differed between the two forms of stimulation. Training resulted in a significant increase in MVC torque for the resistance-training group, but not the control group. There were no statistically significant changes in the corticospinal properties measured at rest for either group. For the active trials involving both TMS and TES, however, the slope of the relationship between MEP size and the torque exerted was significantly lower after training for the resistance-training group (P < 0.05). Thus, for a specific level of muscle activity, the magnitude of the EMG responses to both forms of transcranial stimulation were smaller following resistance training. These results suggest that resistance training changes the functional properties of spinal cord circuitry in humans, but does not substantially affect the organisation of the motor cortex.

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Tissue responses to the application of Rototags and Jumbo Rototags in the first dorsal fin of Carcharhinus melanopterus, C. obscurus and C. plumbeus were examined. The acute response included tissue tearing and haemorrhage and was present by 5 days post-tagging. The intermediate response had begun by 20 days post-tagging and continued beyond 207 days. This response involved decreased red blood cell activity as the inflammatory response commenced. The chronic response had begun by 301 days and was complete by 553 days with a layer of fibrous connective tissue walling off the tag. External damage to the fin was caused by continued abrasion by the tag. Repair scales were observed at 242 days using scanning electron microscopy and were confirmed histologically in 61- and 553-day samples. Repair scales were not seen in areas of continuous abrasion. No infection was observed in tissues surrounding the wound. Disruption of the fin surface was observed due to abrasion by the tag, but did not appear to cause a severe tissue reaction. The tissue responses observed were consistent with a normal, but relatively slow, healing in the vicinity of the tag wound. Use of Rototags or Jumbo Rototags appears to be an efficient way of marking elasmobranchs with minimal damage to the shark. (C) 1998 The Fisheries Society of the British Isles.

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The deep-sea pearleye, Scopelarchus michaelsarsi (Scopelarchidae) is a mesopelagic teleost with asymmetric or tubular eyes. The main retina subtends a large dorsal binocular field, while the accessory retina subtends a restricted monocular field of lateral visual space. Ocular specializations to increase the lateral visual field include an oblique pupil and a corneal lens pad. A detailed morphological and topographic study of the photoreceptors and retinal ganglion cells reveals seven specializations: a centronasal region of the main retina with ungrouped rod-like photoreceptors overlying a retinal tapetum; a region of high ganglion cell density (area centralis of 56.1x10(3) cells per mm(2)) in the centrolateral region of the main retina; a centrotemporal region of the main retina with grouped rod-like photoreceptors; a region (area giganto cellularis) of large (32.2+/-5.6 mu m(2)), alpha-like ganglion cells arranged in a regular array (nearest neighbour distance 53.5+/-9.3 mu m with a conformity ratio of 5.8) in the temporal main retina; an accessory retina with grouped rod-like photoreceptors; a nasotemporal band of a mixture of rod-and cone-like photoreceptors restricted to the ventral accessory retina; and a retinal diverticulum comprised of a ventral region of differentiated accessory retina located medial to the optic nerve head. Retrograde labelling from the optic nerve with DiI shows that approximately 14% of the cells in the ganglion cell layer of the main retina are displaced amacrine cells at 1.5 mm eccentricity. Cryosectioning of the tubular eye confirms Matthiessen's ratio (2.59), and calculations of the spatial resolving power suggests that the function of the area centralis (7.4 cycles per degree/8.1 minutes of are) and the cohort of temporal alpha-like ganglion cells (0.85 cycles per degree/70.6 minutes of are) in the main retina may be different. Low summation ratios in these various retinal zones suggests that each zone may mediate distinct visual tasks in a certain region of the visual field by optimizing sensitivity and/or resolving power.

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Chondroitin sulfate proteoglycans display both inhibitory and stimulatory effects on cell adhesion and neurite outgrowth in vitro. The functional activity of these proteoglycans appears to be context specific and dependent on the presence of different chondroitin sulfate-binding molecules. Little is known about the role of chondroitin sulfate proteoglycans in the growth and guidance of axons in vivo. To address this question, we examined the effects of exogenous soluble chondroitin sulfates on the growth and guidance of axons arising from a subpopulation of neurons in the vertebrate brain which express NOC-2, a novel glycoform of the neural cell adhesion molecule N-CAM. Intact brains of stage 28 Xenopus embryos were unilaterally exposed to medium containing soluble exogenous chondroitin sulfates. When exposed to chondroitin sulfate, NOC-2(+) axons within the tract of the postoptic commissure failed to follow their normal trajectory across the ventral midline via the ventral commissure in the midbrain. Instead, these axons either stalled or grew into the dorsal midbrain or continued growing longitudinally within the ventral longitudinal tract. These findings suggest that chondroitin sulfate proteoglycans indirectly modulate the growth and guidance of a subpopulation of forebrain axons by regulating either matrix-bound or cell surface cues at specific choice points within the developing vertebrate brain. (C) 1998 Academic Press.

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The effect of N-2 respiration on cerebral blood flow (CBF) velocity on the dorsal surface of cerebellum was examined in the estuarine crocodile, Crocodylus porosus, using epi-illumination microscopy. Twelve minutes of N-2 respiration resulted in a 126% increase in CBF velocity. N-2 respiration had no effect on blood pressure, indicating an underlying cerebral vasodilation. In addition, heart rate increased significantly. Systemic injections of aminophylline and the NO synthase (NOS) inhibitor nitro-L-arginine (L-NA) did not affect the hypoxia induced increase in CBF. We conclude that C. porosus responds to hypoxia with adenosine and nitric oxide (NO) independent cerebral vasodilation, and that this is likely to be a mechanism protecting the brain from energy deficiency during prolonged dives. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.

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Three defensin-like peptides (DLPs) were isolated from platypus venom and sequenced. One of these peptides, DLP-1, was synthesized chemically and its three-dimensional structure was determined using NMR spectroscopy. The main structural elements of this 42-residue peptide were an anti-parallel beta-sheet comprising residues 15-18 and 37-40 and a small 3(10) helix spanning residues 10-12. The overall three-dimensional fold is similar to that of beta-defensin-12, and similar to the sodium-channel neurotoxin ShI (Stichodactyla helianthus neurotoxin I). However, the side chains known to be functionally important in beta-defensin-12 and ShI are not conserved in DLP-1, suggesting that it has a different biological function. Consistent with this contention, we showed that DLP-1 possesses no anti-microbial properties and has no observable activity on rat dorsal-root-ganglion sodium-channel currents.