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R. Borges-Argez L. Balnbury A. Flowers A. Gimnez-Turba G. Ruiz P.G. Waterman L.M. Pea-Rodríguez 《Phytomedicine》2007,14(7-8):530-533
A number of flavonoids isolated from Lonchocarpus spp. were evaluated for their antiprotozoal and cytotoxic activity. Flavone 6 and chalcone 7 were found to be the most active against Leishmania parasites and against cell cultures of Leukemia P388DI and adenocarcinoma prostate PC-3. 相似文献
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P. Cruz C. H. Mejia‐Ruiz R. Perez‐Enriquez A. M. Ibarra 《Molecular ecology resources》2002,2(3):239-241
Five polymorphic microsatellite loci were characterized for Penaeus (Litopenaeus) vannamei. Loci were isolated using a partial Sau3A1 genomic library by the sequencing of randomly selected clones and by a biotinylated (CT)10 and (GT)10 probes screening procedure. The last strategy resulted in the most useful data. About 40% of the clones showed a previously reported satellite/microsatellite (PVS1), reducing the chance of finding new microsatellite regions. Whereas two of the microsatellite loci with more than 10 alleles will be useful for mating analysis in a breeding program, the others might prove useful for population genetic studies. 相似文献
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In the River Lobos-Ucero and its tributary the River Avión-Milanos (Duero basin, Old Castile, Central Spain), two limestone streams fed by aquifers, the population of brown trout, as compared with the populations of other European streams, shows a high growth rate, high condition coefficients, short life-span and early age at first maturity. Gonad cycle was also studied. Size distributions of unshed eggs exhibit a dynamic activity with a bi-modal distribution from June onwards, spawning occurred in the last days of November. Fecundity (F) can be predicted from trout length (L, mm) according to the equation: F= –646.47+5.6167 · L. Numbers and standing crop of trout range from 18 to 3903 ind. ha–1 and 3.6 to 452.9 Kg ha–1, reaching higher values in the sites close to the aquifers. Egg production had values of 22.4 and 18.0 eggs m–2 in the Rivers Ucero and Avión-Milanos respectively. Some factors suggested as regulators of these demographical characteristics are discussed in the light of recent literature. 相似文献
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Fabián Michelangeli Dalia M. Sulcas Marie-Christine Ruiz 《Cell and tissue research》1987,250(2):413-419
Summary This study is concerned with electron-microscopic observations on endocrine or paracrine cells in the fundic gastric mucosa of the bullfrog. Also, an attempt was made to identify the histamine-releasing cells involved in the secretagogue response. At least three distinct endocrine-like cell types were found. The classification is based on the appearance of secretory granules and other organelles, and the relationship of endocrine-like cells with other cells in the tissue. The amphibian endocrine-like cells resemble the ECL, D and EC cells of mammals. Type-I (ECL) cells showed degranulation after repeated stimulation with tetragastrin (TG), acetylcholine (ACh) and K+ depolarizing solution, all of which release histamine. 相似文献