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741.
Y Menezo A Cupo L Bueno 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1987,304(12):337-340
In search of early pregnancy factors, we detected by radioimmunoassay the presence of enkephalin in bovine and human corpus luteum. In vitro met-enkephalin release by bovine corpus luteum is about 0.5 to 1 pmole/mg of fresh tissue/24 hrs. The content of the fresh tissue is between 0.7 and 1.9 pmoles per gram of human tissue, and 0.9 pmoles for bovine tissue. Furthermore, we determined the presence of leu-enkephalin and met-enkephalin Arg-Gly-Leu to. The ratios observed confirm a pro-enkephalin A expression in the ovary. Opiates or opioid-like peptides are present in the female genitalia at the time of early embryo development. The roles of these opioid peptides is discussed in term of ovum transport, granulosa cell physiology and early pregnancy factors. 相似文献
742.
Walter A. Boeger Delane C. Kritsky Luciana Patella Marlus Bueno‐Silva 《Zoologica scripta》2021,50(1):112-124
Phylogenetic analyses of sequences of the 18S rDNA and MT‐CO2 gene fragments indicated that the oviparous and viviparous gyrodactylid‐like monogenoids formed independent monophyletic clades within the Order Gyrodactylidea, supporting the reinstatement of the Oogyrodactylidae and limiting the Gyrodactylidae to the viviparous species. Analyses further indicated that the clade comprising the two families shared a common ancestor with the Udonellidae. Two clades, that of Aglaiogyrodactylus and that of Phanerothecium, were identified within the Oogyrodactylidae, while Onychogyrodactylus was shown to be polyphyletic and Oogyrodactylus basal within the family. One putative synapomorphy was identified for the Oogyrodactylidae, that is presence of a massive Mehlis’ gland. The Gyrodactylidae was limited to species having a viviparous mode of reproduction, although relationships within the family were generally poorly resolved. Several putative synapomorphies were found for the Gyrodactylidae, including viviparity and protogyny, a bulbous and armed MCO, absence of a vitellarium, and presence of a knob‐like deep anchor root (Fig. 3e). Ultrametric analyses suggested that the initial divergence of the clade of the gyrodactylid‐like monogenoids and Udonellidae occurred about 335 mya (based on the 18S rDNA fragment) and about 400 mya (based on the MT‐CO2 gene fragment). Using the 18S rDNA fragment and three calibration points, ultrametric analyses indicated that the Gyrodactylidae and Oogyrodactylidae diverged at approximately 278 mya, with initial diversification within the Gyrodactylidae (about 211 mya) occurring earlier than that of the Oogyrodactylidae (about 133 mya), the latter coinciding with the breakup of Gondwana and the initial diversification of the armoured catfishes (Loricariidae). Finally, diagnoses were provided for the Gyrodactylidae and Oogyrodactylidae along with a list of genera assigned to each family. 相似文献
743.
744.
Junio Tavares Amaro Adeney de Freitas Bueno Pedro Manuel Oliveira Janeiro Neves Débora Mello da Silva Aline Pomari-Fernandes Bruna Magda Favetti 《Revista Brasileira de Entomologia》2018,62(3):195-197
The selectivity of five entomopathogens and a chemical insecticide (positive control) to pupae and adults of the egg parasitoid Telenomus remus (Nixon) was evaluated in the laboratory under controlled environmental conditions according to protocols established by the International Organization for Biological Control. Baculovirus anticarsia (Baculovirus AEE®), Bacillus thuringiensis var. kurstaki (Thuricide®), Bacillus thuringiensis var. aizawai (Agree®), Beauveria bassiana (Boveril®), Metarhizium anisopliae (Metarril®) and Trichoderma harzianum (Trichodermil®) are harmless to T. remus pupae, and adults. Thus, our results suggest that the insect control strategies applied here are compatible since entomopathogens were classified as harmless to T. remus in most examined cases and therefore facilitate a joint application to control different pests. Bacillus thuringiensis var. kurstaki (Dipel®), despite being classified as slightly harmful in some of the evaluations, can still be considered compatible for use together with T. remus, especially when compared with chemical insecticides such as chlorpyrifos that might be considered harmful to the parasitoid survival. 相似文献
745.
Myocyte differentiation and body wall muscle regeneration in the planarian Girardia tigrina 总被引:2,自引:0,他引:2
F. Cebrià Marcelo Vispo P. Newmark David Bueno Rafael Romero 《Development genes and evolution》1997,207(5):306-316
Freshwater planarians (Platyhelminthes, Turbellaria) show a great degree of morphological plasticity, making them a useful
model for studying cell differentiation and pattern restoration processes during regeneration. Using confocal microscopy and
a monoclonal antibody specific for muscle cells (TMUS-13), we have monitored the restoration of the body wall musculature
during head regeneration in whole-mount organisms. Our results show that until the 4th day of regeneration the blastema is
occupied by very disorganized muscle fibers, that from this moment become progressively organized restoring the original muscle
pattern. In addition to recognizing mature muscle cells, TMUS-13 also recognizes differentiating myocytes, allowing us to
trace the origin of newly formed muscle cells. We report that myocytes are detected in the postblastema region as early as
day 1 of regeneration. This is the first demonstration that, in addition to serving as a proliferative zone as previously
described, overt differentiation begins in the postblastema, at least for muscle cells. We also show that the TMUS13 antigen
is the myosin heavy-chain gene from planarians.
Received: 15 April 1997 / Accepted: 7 July 1997 相似文献