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The brown alga Lobophora (Dictyotales, Phaeophyceae) is an important macroalga in the North-eastern Atlantic archipelagos (i.e., Macaronesia). Notably in the Canaries it can dominate benthic assemblages. While the genus has been the subject of several ecological studies in the Canaries, no study has yet been conducted to assess species-level diversity of Lobophora in Macaronesia. We reassessed the diversity of Lobophora in Macaronesia, reporting the presence of seven species (L. caboverdeana sp. nov., L. canariensis, L. dagamae sp. nov., L. delicata, L. dispersa, L. littlerorum, and L. schneideri). Lobophora spp. from Macaronesia are morphologically and ecologically distinguishable. In the Canaries, L. schneideri dominates the photophilic assemblages from the intertidal to 20-30 m depth. Lobophora dagamae sp. nov. grows in less illuminated shallow habitats, and replaces L. schneideri from 30 to ~80 m. Lobophora canariensis also has a wide vertical distribution, from the intertidal to deep waters, while L. delicata, L. dispersa and L. littlerorum grow in shallow waters. The dominance of species with an upright habit versus prostrate or crustose species may be mediated by the pressure of herbivores. Four species have an amphi-Atlantic distribution: L. littlerorum, L. canariensis, L. delicata, and L. schneideri. Lobophora schneideri and L. delicata are furthermore distributed in the Mediterranean Sea. By sampling a pivotal region in the Atlantic, this study significantly improves our knowledge of Lobophora biogeography in the Atlantic Ocean. Macaronesia constitutes a species–poor region for Lobophora where no diversification events occurred, and a region of overlap between the Greater Caribbean and the Indo-Pacific.  相似文献   
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A case of paracoccidioidomycosis with ocular involvement is studied. Brazilian literature is reviewed. The scarcity of human ocular mycosis is commented on. The most frequent clinic aspects of ocular lesions in natural mycosis are described.
Resumo Um caso de paracoccidioidomicose pulmonar e linfática seguido de comprometimento conjuntivo-palpebral é estudado, em São Paulo.A literatura nacional é revista. As lesões oculares, mais frequentemente verificadas, na paracoccidioidomicose natural são descritas, minuciosamente. O pequeno número de casos humanos com comprometimento ocular é discutido.A severidade e a frequencia das lesões oculares em animais inoculados intracardiacamente, com cultivos de P. brasiliensis sugerem disseminação hematogênica ocular da paracoccidioidomicose humana.
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One mechanism by which marine organisms may respond to climate shifts is range shifts. The corkwing wrasse (Symphodus melops) is a temperate fish species, inhabiting the coasts of Europe, that show strong indications of current as well as historical (ice-age) range shifts towards the north. Nine neutral microsatellite DNA markers were screened to study genetic signatures and spatial population structure over the entire geographic and thermal gradient of the species from Portugal to Norway. A major genetic break (F ST  = 0.159 average among pairs) was identified between Scandinavian and more southern populations, with a marked reduction (30% or more) in levels of genetic variability in Scandinavia. The break is probably related to bottleneck(s) associated with post-glacial colonization of the Scandinavian coasts, and indicates a lack of present gene flow across the North Sea. The lack of gene flow can most likely be attributed to the species’ need for rocky substrate for nesting and a relatively short pelagic larval phase, limiting dispersal by ocean currents. These findings demonstrate that long-distance dispersal may be severely limited in the corkwing wrasse, and that successful range-shifts following present climate change may be problematic for this and other species with limited dispersal abilities, even in the seemingly continuous marine environment.  相似文献   
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Root hypoxia produced by flooding or over-irrigation limits stone fruit tree development, particularly in orchards established on soils with restricted drainage. To overcome this problem, stone fruit trees are usually grafted on rootstocks (species or hybrid of the Prunus L. genus) with different degrees of tolerance to root hypoxia. However, the molecular base of such variability is largely unknown. In Arabidopsis thaliana (Heynh.), as well as in a number of crops and tree species, hemoglobin (Hb)-like genes stand out among hypoxia-related genes, but no such studies have been done with the Prunus species used as rootstocks. In this study, we analyzed the expression pattern of class 1 non-symbiotic Hb-like (nsHb) and class 3 truncated Hb-like (trHb) genes in Prunus rootstock roots with different responses to this stress. We observed that the putative Prunus nsHb and trHb genes were induced by root hypoxia in all analyzed Prunus genotypes, independently of their tolerance to hypoxia. However, Prunus nsHb and trHb genes had higher expression levels in roots of tolerant rootstocks. Prunus nsHb and trHb genes were also regulated by other abiotic stresses, such as salt stress and low temperatures. Our results suggest that changes in nsHb and trHb expressions could be part of the adaptive mechanisms that have evolved in the Prunus species to survive under hypoxia or other types of environmental stress that commonly challenge stone fruit tree orchards.  相似文献   
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Increased interleukin-6 (IL-6) plasma levels have been described to occur during physical exercise. A relative reduction in energy intake after physical activity has also been reported after exercise, indicating a possible involvement of IL-6 as an anorexigenic factor. Given the possible effect of interleukins on appetite, we assessed whether a controlled physical activity bout is related with changes in IL-6, IL-6 soluble receptor (IL-6sR), gp130 and interleukin-18 (IL-18) plasma levels, as well as their relation with post-exercise energy intake. A co-twin intervention study was carried out with five young male monozygotic twin pairs. One co-twin performed 45 min of submaximal exercise on a treadmill near the anaerobic threshold ending with 7 min at 90 % VO2 max, while his co-twin remained non-active. Ad libitum energy intake was tested through a carbohydrate-rich meal test. Venous blood samples were drawn at baseline, immediately after exercise and after the meal ingestion. Plasma concentrations of IL-6, IL-6sR, gp130 and IL-18 were measured via ELISA. IL-6 plasma levels increased after physical activity bout (2.6-fold change; p?=?0.04). A less marked trend, although still significant, was observed for plasma levels of IL-6sR and gp130. Plasma levels of IL-18 did not significantly change during exercise. The twins who exercised exhibited significantly lower energy intake (181 versus 1,195 kcal; p?=?0.04), compared to the co-twins who remained resting. The present study in monozygotic twins shows increased IL-6 plasma levels after acute physical exercise with a significant reduction in energy intake, supporting a linkage between IL-6 and acute post-exercise eating behaviour.  相似文献   
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