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排序方式: 共有189条查询结果,搜索用时 15 毫秒
1.
Six young tortoises Testudo marginata Schoepff, 1792 were experimentally infected with Hemolivia mauritanica (Sergent et Sergent, 1904). The prepatent period ranged from 6 to 8 weeks. Young, smaller, club-like forms (6-9 x 3-6 Am) of gametocytes appeared in the peripheral blood first, whereas mature, elongated, cylindrical forms (9-12 x 5-7 Am) were detected after 1-2 weeks and predominated during later patency. Three of the infected tortoises were euthanized and dissected to study the endogenous stages. Meronts occurred in the cells of the reticulo-endothelial system and in the erythrocytes; these were observed mostly in parenchymatous organs. Mature forms measured 14.2 x 9.3 microm and contained 7-12 merozoites. Cysts with two (exceptionally one) cystozoites were also found predominantly in parenchymatous organs and measured 14.8 x 7.9 microm. Pathological changes attributable to Hemolivia were mild and limited to liver and kidneys. The role of individual developmental stages of haemogregarines is discussed with respect to evolution of heteroxenous life cycle and long-term persistence of parasites in their intermediate hosts. 相似文献
2.
éverton Tenório de Souza Daysianne Pereira de Lira Aline Cavalcanti de Queiroz Diogo José Costa da Silva Anansa Bezerra de Aquino Eliane A. Campessato Mella Vitor Prates Lorenzo George Emmanuel C. de Miranda Jo?o Xavier de Araújo-Júnior Maria Célia de Oliveira Chaves José Maria Barbosa-Filho Petr?nio Filgueiras de Athayde-Filho Bárbara Viviana de Oliveira Santos Magna Suzana Alexandre-Moreira 《Marine drugs》2009,7(4):689-704
The antinociceptive and anti-inflammatory activity of caulerpin was investigated. This bisindole alkaloid was isolated from the lipoid extract of Caulerpa racemosa and its structure was identified by spectroscopic methods, including IR and NMR techniques. The pharmacological assays used were the writhing and the hot plate tests, the formalin-induced pain, the capsaicin-induced ear edema and the carrageenan-induced peritonitis. Caulerpin was given orally at a concentration of 100 μmol/kg. In the abdominal constriction test caulerpin showed reduction in the acetic acid-induced nociception at 0.0945 μmol (0.0103–1.0984) and for dypirone it was 0.0426 μmol (0.0092–0.1972). In the hot plate test in vivo the inhibition of nociception by caulerpin (100 μmol/kg, p.o.) was also favorable. This result suggests that this compound exhibits a central activity, without changing the motor activity (seen in the rotarod test). Caulerpin (100 μmol/kg, p.o.) reduced the formalin effects in both phases by 35.4% and 45.6%, respectively. The possible anti-inflammatory activity observed in the second phase in the formalin test of caulerpin (100 μmol/kg, p.o.) was confirmed on the capsaicin-induced ear edema model, where an inhibition of 55.8% was presented. Indeed, it was also observed in the carrageenan-induced peritonitis that caulerpin (100 μmol/kg, p.o.) exhibited anti-inflammatory activity, reducing significantly the number of recruit cells by 48.3%. Pharmacological studies are continuing in order to characterize the mechanism(s) responsible for the antinociceptive and anti-inflammatory actions and also to identify other active principles present in Caulerpa racemosa. 相似文献
3.
Marek Šmejkal Marie Prchalová Martin Čech Mojmír Vašek Milan Říha Tomáš Jůza Petr Blabolil Jan Kubečka 《Ecology of Freshwater Fish》2014,23(3):405-413
Fish associations with different types of littoral habitats were studied in four canyon‐shaped reservoirs in the Czech Republic in years 2010 and 2011 by gillnets. Two to three habitats per reservoir–beaches (former meadows), stump fields (former forest) and rubble slopes–were defined and sampled along the longitudinal axis of reservoirs. Effects of reservoir, habitat and locality (position along longitudinal axis) on fish biomass, abundance and species structure were tested for juvenile and adult fish separately. Hierarchical analysis of variance revealed that habitats differed significantly in fish biomass and abundance. Redundancy analysis showed that analysed environmental variables had significant influence on fish community structure. Most variability in community structure was explained by reservoir and then by combination of habitat and slope steepness. Locality position had the smallest influence on community structure. For both adult and juvenile fish total abundance and biomass, the most inhabited habitat was beaches; rubble slopes were the least inhabited. Habitat associations differed among species. Among adults, bream Abramis brama, white bream Blicca bjoerkna and roach Rutilus rutilus were associated with beaches and stump fields, whereas perch Perca fluviatilis, ruffe Gymnocephalus cernuus, asp Aspius aspius and pike Esox lucius were associated with rubble slopes. Bream, white bream, bleak Alburnus alburnus, roach, ruffe and pikeperch Sander lucioperca were associated with beaches among juveniles, whereas the only juvenile associated with rubble slopes was perch. We showed that most common species are associated with distinct habitats and also that utilisation of various littoral habitats differs in general. 相似文献
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The occurrence of sleep disorder in three half sibling Lipizzaner is described. Sleepiness, swaying, stumbling, carpal joints buckling and falling down onto the carpal joints had been present since early foal age in all of them. Clinical signs had gradually reduced since the age of 2 years in cases 1 and 3. Sleepiness was induced by going out from the stable in adulthood. A physostigmine test was performed in all three affected horses and produced positive results in cases 1 and 3. The result of the test in case 2 was unclear due to the almost continuous sleepiness of the foal. Hypocretin-1 concentration in the cerebrospinal fluid was established using a standardised radioimmunoassay in case 1 (317.85?pg/mL), case 2 (303.43?pg/mL) and five adult control horses (275.2?±?47.9 [SD] pg/mL) and was considered as normal in all horses. The sire of the affected horses has had 19 other registered offspring who did not show clinical signs of sleep disorder and also dams of all three cases produced healthy foals. Based on the demographic and clinical data together with the responses to the physostigmine challenges, the diagnosis of familial equine narcolepsy was made. 相似文献
6.
Petra FRÝDLOVÁ Jan HNÍZDO Lenka CHYLÍKOVÁ Olga ŠIMKOVÁ Veronika CIKÁNOVÁ Petr VELENSKÝ Daniel FRYNTA 《Integrative zoology》2013,8(Z1):39-45
Blood cell morphology and count are not uniform across species. Recently, between‐species comparisons revealed that the size of red blood cells is associated with body size in some lizard taxa, and this finding was interpreted in the context of the metabolic theory. In the present study, we examined the numbers and the size of blood cells in 2 species of monitor lizards, the mangrove‐dwelling monitor (Varanus indicus) and the savannah monitor (V. exanthematicus), and we compared these traits in individuals of different body size. The results revealed that during the course of ontogeny, the size of red blood cells increases with body mass. Because the mass‐specific metabolic rate decreases with body size and the cell volume‐to‐surface ratio decreases with the cell size, changes in the erythrocyte size might be the result of oxygen transport adjustment. 相似文献
7.
Petr Slama Zbysek Sladek Dusan Rysanek Tereza Langrova 《Research in veterinary science》2009,87(2):233-238
The aim of this study was to determine whether lymphocyte apoptosis is modulated by infections caused by Staphylococcus aureus and Streptococcus uberis. Samples of cell populations were obtained by lavage of the mammary glands at 4 intervals (24, 48, 72 and 168 h) following infection. The percentage of apoptotic lymphocytes peaked at 168 h after challenge with S. aureus or S. uberis. Subsequent experiments focused on in vitro cultivation of mammary gland lymphocytes with S. aureus and S. uberis. These experiments showed a lower percentage of apoptotic lymphocytes following 3 h of cultivating cells with bacteria than after cultivation without bacteria. The results demonstrate that during both experimental infection of bovine mammary glands with S. aureus or S. uberis and during in vitro cultivation of lymphocytes with S. aureus or S. uberis, apoptosis of lymphocytes is delayed. 相似文献
8.
Petr Starý 《Anzeiger für Sch?dlingskunde》2000,73(3):75-78
A supplementary research on Russian wheat aphid (= RVA), Diuraphis noxia (Kurdj.) between 1998-99 documented the pest distribution all over the Czech republic already. RVA abundance was proved to be significantly area-dependent within the state. The banker areas are in southern Moravia (district Znojmo, the frontier area near Austria) up to central Moravia. The determined RWA distribution area is much broader than presumed on grounds of climatic characteristics.The abundance of RVA generally decreases from the SE to the NW and N direction, as well as with the increasing altitude within the area.The highest altitude a.s.l. of RWA occurrence in the crop was 762 in. The re-classified main expansion route was determined to follow two directions (sourcing from Hungary and Austria) to southern-central-northem Moravia, and to southern Bohemia and further on to the central Bohemian lowland. The field information indicated the development of preference of RWA for barley. 相似文献
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