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761.
Valentin Jean L.; Monteiro-Ribas Wanda M.; Mureb M. Anita; Pessotti Eliane 《Journal of plankton research》1987,9(6):1195-1216
On some zooplankters common in the Cabo Frio (Brazil) upwelling.In the waters off Cabo Frio zooplankton maxima are observedbetween February and April, which is the period of upwellingoccurrence. Copepods are highly diversified; we identified 96species at a single collecting station during one year. In summerCalanoides carinatus, Paracalanus parvus and Oncea media areabundant, whereas we observed dominance of Temora stylifera,Clausocalanus furcatus, C. arcuicomis, Oithona plumifera andgreat quantity of Creseis acicula during winter. Chaetognatha(Sagitta enflata), Appendicularia (Oikopleura longicauda), Ostracoda(Conchoecia spp.) and Pteropoda (Limacina sp.) are permanentthroughout the year, and maximum in summer. The vertical distributionof zooplankton depends on the hydrological structure, i.e. natureof the water mass and degree of mixing between different waters.Brazil current water, with low quantity of organisms and dominanceof copepods (Clausocalanus furcatus, Mecynocera clausi, Corycaeidae,Oithonidae, Oncaeidae) accompanied by Evadne spinifera and Lucifertypicus. South Atlantic Central Water (upwelling water) characterizedby rare deep copepods and abundance of Calanoides carinatusand Ctenocalanus vanus which are excellent indicator speciesfor upwelling occurrence. Coastal water, with low salinity,where some species with brackish affinity are observed, likeOithona ovalis and Podon polyphemoides. 相似文献
762.
Chapmannia Torrey & Gray, a monotypic legume genus of Florida, is shown to have perfect flowers, rather than sterile and fertile flowers incorrectly attributed to the genus by authors for the past one hundred years. The species is described and illustrated with accompanying notes on its habitat, distribution, reproductive biology, phylogeny and cytology. 相似文献
763.
Pachecoa Standley & Steyerm., a monotypic legume genus of Mexico, Guatemala, and Venezuela, is described and illustrated with accompanying notes on its habitat, distribution, reproductive biology, phylogeny, cytology, and relationship (with key) to allied genera. 相似文献
764.
Anapaula Sommer Vinagre Ana Paula Nunes do Amaral Fabiana Pinto Ribarcki Eliane Fraga da Silveira Eduardo Prico 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2007,146(4):514
The aim of this study was to analyze the seasonal variations of carbohydrate and lipid metabolism of the ghost crab Ocypode quadrata (Fabricius, 1787) on a sandy beach in the southern region of Brazil. Crabs and hemolymph samples were collected monthly in the field. Hepatopancreas, gills, gonads and claw muscles were used for glycogen determination. In males, blood glucose levels increased in the summer and in the winter. The glycogen values increased significantly in the hepatopancreas in the winter, but remained constant in the muscle, gonads and gills. In females, hemolymph glucose levels, glycogen values in the hepatopancreas and in the gills remained constant throughout the year; however, muscular glycogen increased in the spring and gonad glycogen decreased in the summer. Hemolymph triglyceride levels of males and females and total cholesterol of males decreased significantly in the spring. In females, a significant increase of total cholesterol levels was found in the winter. The findings suggest that in O. quadrata lipids seem to be an important reserve of energy used during reproduction, both in males and females, while glycogen may be used during periods of intense activity or fasting. 相似文献
765.
Eliane Noirot 《Animal behaviour》1974,22(2):410-420
When a naïve virgin female mouse is exposed to an inaccessible litter so that it perceives the odour and the ultrasounds from the pups, its nest-building behaviour undergoes changes that are different from changes occurring in a control condition providing exposure to an inaccessible adult female. Virgin females exposed to a litter built their nest as near as possible to the pups. Other characteristics of their nest-building behaviour were influenced differently according to the type of ultrasound that the pups were emitting. In a condition where pups were mainly calling in response to cold, virgin females built heavier nests than control females. When mainly calls in response to handling were given by the pups, the females built lighter nests than control females. Finally, there was also some suggestion that the females exposed to ultrasounds from handled pups tended to chew the nest-material more than either control females or females exposed to ultrasound from cooled pups. 相似文献
766.
H. Taina Darius Catherine Dauga Patrick A. D. Grimont Eliane Chungue Paul M. V. Martin 《The Journal of eukaryotic microbiology》1998,45(6):619-627
ABSTRACT The diversity of symbiotic dinoflagellates (SD) from seven coral species ( Fungia scutaria, Fungia paumotensis, Lep-tastrea transversa, Pavona cactus, Pocillopora verrucosa, Montastrea curia , and Acropora fonnosa ) was studied in a restricted geographical area, the Lagoon of Arue on the island of Tahiti. Their diversity was explored by small subunit ribosomal RNA gene (SSU rDNA) restriction fragment length polymorphism (RFLP). After a nested amplification with SD specific primers, RFLP analyses were performed directly and after a cloning step. The diversity of these different SSU rDNA was estimated in respect to possible technical artifacts. In an axenic culture of SD from the coral Galaxea fascicularis , both heterogeneous SSU rDNAs and artifact molecules were observed as in our SD samples. According to the number of patterns observed, corals Fungia paumotensis, Leptastrea transversa. Pavona cactus, Montastrea curia, and Acropora fonnosa contained one class of SD SSU rDNAs. whereas Fungia scutaria and Pocillopora verrucosa contained three and two classes of SD SSU rDNAs respectively. In the limited geographic area studied. SD from different coral species shared the same pattern, except SD from Montastrea curta , which showed a unique pattern. In addition to the possibility of SD flux among different coral species, specific mechanisms could also be involved in the establishment of a symbiosis. 相似文献
767.
Mechanical loading regulates NOS expression and activity in developing and adult skeletal muscle 总被引:10,自引:0,他引:10
Tidball James G.; Lavergne Eliane; Lau Kim S.; Spencer Melissa J.; Stull James T.; Wehling Michelle 《American journal of physiology. Cell physiology》1998,275(1):C260
The hypothesis that changes in muscle activation and loadingregulate the expression and activity of neuronal nitric oxide (NO)synthase (nNOS) was tested using in vitro and in vivo approaches. Removal of weight bearing from rat hindlimb muscles for 10 days resulted in a significant decrease in nNOS protein and mRNAconcentration in soleus muscles, which returned to controlconcentrations after return to weight bearing. Similarly, theconcentration of nNOS in cultured myotubes increased by application ofcyclic loading for 2 days. NO release from excised soleus muscles wasincreased significantly by a single passive stretch of 20% or bysubmaximal activation at 2 Hz, although the increases were not additivewhen both stimuli were applied simultaneously. Increased NO release resulting from passive stretch or activation was dependent on thepresence of extracellular calcium. Cyclic loading of cultured myotubesalso resulted in a significant increase in NO release. Together, thesefindings show that activity of muscle influences NO production in theshort term, by regulating NOS activity, and in the long term, byregulating nNOS expression. 相似文献