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21.
Joana Pais De Faria Vitor H. Paiva Sara N. Veríssimo Catarina S. Lopes Rita Soares João Oliveira Ivo dos Santos Ana C. Norte Jaime A. Ramos 《Ibis》2023,165(1):312-321
Gulls, as largely flexible opportunistic individuals, have been increasingly breeding in many cities around the world, but it is still unclear whether urban habitats are of equal or higher quality than traditional natural habitats or represent an ecological trap with immediate reproductive benefits but longer-term detrimental consequences to health. Here we present a study of breeding parameters (nest density, egg dimensions, clutch size, hatching success and adult body condition) and physiological parameters (erythrocyte sedimentation rate, heterophil/lymphocyte ratio, haemoglobin concentration and measurements of oxidative stress) as indicators of the general health condition of Yellow-legged Gull Larus michahellis adults and chicks from natural and urban colonies. Yellow-legged Gulls in the largest urban area (Porto) laid smaller eggs and clutches, showed a significantly lower occurrence of inflammatory processes in chicks, and showed a slower early chick growth than in the natural colony of Deserta. This suggests that urban gulls might be facing important trade-offs between the advantages of breeding in lower density urban colonies, with fewer intraspecific interactions and a lower disease transmission probability, and the disadvantages of having an anthropogenic diet usually lower in nutritional value. 相似文献
22.
Molecular cloning of a gene involved in glucose sensing in the yeast Saccharomyces cerevisiae 总被引:6,自引:1,他引:5
Linda Van Aelst Stefan Hohmann Botchaka Bulaya Wim de Koning Laurens Sierkstra Maria José Neves Kattie Luyten Rafael Alijo José Ramos Paola Coccetti Enzo Martegani Neuza Maria de Magalhães-Rocha Rogelio Lopes Brandão Patrick Van Dijck Mieke Vanhalewyn Peter Durnez Arnold W. H. Jans Johan M. Thevelein 《Molecular microbiology》1993,8(5):927-943
23.
24.
Dr J. O. Lopes D. V. Pereira L. A. Streher A. A. Fenalte S. H. Alves J. P. Benevenga 《Mycopathologia》1995,130(2):89-92
A case of cutaneous zygomycosis caused byAbsidia coryabifera in a leukemic patient submitted to chemotherapy is reported. The lesion was located on the little finger of the right hand and probably resulted from a latent osteomyelitis. It progressed to form extensive necrotic area. No systemic infection was detected and the lesion did not appear to be associated with any trauma. 相似文献
25.
Carlos F. de Mello Diego D. De La Vega Leandro T. Pizutti Fabiane P. Lopes Maribel A. Rubin Jaime G. Homerich Dr. Carlos R. Melo Joana E. Somer Diogo O. Souza Moacir Wajner 《Neurochemical research》1995,20(12):1437-1441
The effect ofl-pyroglutamic acid, a metabolite that accumulates in pyroglutamic aciduria, on different neurochemical parameters was investigated in adult male Wistar rats. Glutamate binding, adenylate cyclase activity and G protein coupling to adenylate cyclase were assayed in the presence of the acid.l-pyroglutamic acid decreased Na+-dependent and Na+-independent glutamate binding Basal and GMP-PNP stimulated adenylate cyclase activity were not affected by the acid. Furthermore, rats received unilateral intrastriatal injections of 10–300 nmol of bufferedl-pyroglutamic acid. Vehicle (0.25 M Tris-Cl, pH 7.35–7.4) was injected into the contralateral striatum. Neurotoxic damage was assessed seven days after the injection by histological examination and by weighing both cerebral hemispheres. No difference in histology or weight could be identified between hemispheres. These results suggest that, although capable of interfering with glutamate binding, pyroglutamate did not cause a major lesion in the present model of neurotoxicity. 相似文献
26.
Marcela F. Lopes Vânia Lúcia C. Merquior JoséMauro Peralta Lúcia M. Teixeira 《FEMS immunology and medical microbiology》1995,12(3-4):205-211
Abstract Exosubstances (cohemolysins) produced by Streptococcus agalactiae (CAMP-factor) and Streptococcus uberis (Uberis-factor) showing hemolytic synergism with β-lysin produced by Staphylococcus aureus were compared. Cohemolytic activity was evaluated in the supernatants of bacterial cultures, before and after ammonium sulfate precipitation. Sheep erythrocytes sensitized with β-lysin were used as substrate. The assays were performed in microtiter plates and results were expressed as cohemolytic units/ml. Maximum cohemolytic activity was detected, respectively, after 8 h and 14 h of growth in Columbia broth in S. uberis and S. agalactiae cultures. Cohemolytic activities of both microorganisms showed similarities when submitted to various physical and chemical treatments. They were significantly decreased by heating at 60°C and 100°C, or in presence of trypsin, and were abolished in the presence of Tween 20. Activities were found to be stable in crude supernatants and concentrated preparations maintained at −20°C for 3 months. Differences were related to levels of activity and kinetics of detection during the growth cycle. The results indicate the proteic nature, at least in part, of the Uberis factor. Analysis by PAGE in the presence or absence of SDS allowed us to correlate Uberis activity with a protein band with apparent molecular mass of 42 kDa, while CAMP activity was associated with a protein band of 27 kDa. 相似文献
27.
A. van Rotterdam F. H. Lopes da Silva J. van den Ende M. A. Viergever A. J. Hermans 《Bulletin of mathematical biology》1982,44(2):283-305
A linear spatially distributed model of a chain of neurons and interneurons was investigated in relation to the generation
of propagated alpha rhythmic activity. It was assumed that the elements of the chain were interconnected by means of recurrent
collaterals and inhibitory fibres in such a way that the connectivity functions were assumed to be homogeneous and their strength
was an exponentially decreasing function of distance. It was found that such a neuronal chain shows propagation properties
for frequencies in the alpha band. The results obtained with the model are in agreement with the phase velocities encountered
experimentally. In this way, it was possible to estimate the length of the neural fibres responsible for the phenomenon of
propagated activity. The estimates obtained are in good agreement with recent quantitative neuroanatomical data on the circuitry
of the neocortex. 相似文献
28.
29.
O U Lopes J F Palmer 《Quarterly journal of experimental physiology and cognate medical sciences》1977,62(1):41-53
Electrical stimulation of the "Defence Area" of the hypothalamus in anaesthetized cats was accomplished by stereotaxic placement of bipolar stainless steel electrodes; the spinal cord was sectioned at L4. The muscle blood flow in one hind limb was recorded with an electromagnetic flowmeter. Increases of between 100% and 300% were observed during hypothalamic stimulation. Electroneurographic recordings from small nerve filaments supplying tibialis anterior muscle revealed two populations of neurones whose activity was abolished by lumbar sympathectomy. It appears that the increased blood flow in skeletal muscle during stimulation of the hypothalamic "Defence Area" is brought about by a simultaneous inhibition of vasoconstrictor activity and increase in cholinergic vasodilator discharge. 相似文献
30.
Marcia R. Brochetto-Braga Suely Lopes Gomes JoséCarlos Da Costa Maia 《Archives of biochemistry and biophysics》1982,217(1):295-304
Using a combination of Chromatographic and sucrose density gradient techniques under carefully controlled conditions of pH and protease inhibitors, we demonstrate that there is only one form of adenosine 3′,5′-monophosphate-dependent protein kinase in the cytosol fraction of the Blastocladiella emersonii zoospore. If any of these conditions are omitted during extract preparation, one obtains what are apparently multiple forms of the enzyme, which are in reality artifacts due to extensive endogenous proteolytic activity. This endogenous protease is stimulated by alkaline pH and inhibited by antipain. The zoospore protein kinase is similar to type II protein kinase from mammalian cells in several aspects including Chromatographic behavior on DEAE-cellulose column, conditions for subunit dissociation and reassociation, as well as the molecular weight value of the regulatory subunit. 相似文献