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Campos E Moraes J Façanha AR Moreira E Valle D Abreu L Manso PP Nascimento A Pelajo-Machado M Lenzi H Masuda A Vaz Ida S Logullo C 《Veterinary parasitology》2006,138(3-4):349-357
The present work evaluates the kinetics of utilization of the main potential energy sources throughout the embryonic developmental stages of Boophilus microplus. The embryonic development of this arthropod is completed in 21 days. Cellularization of the blastoderm occurs on the 6th day and is rapidly followed by germ band extension and segmentation, whose first signs are visible on the 7th day. Cellularization is typically a maternal-driven process, carried out by molecular determinants deposited in the oocyte during oogenesis. On the other hand, segmentation is of zygotic nature, being the consequence of the synthesis of various components by the growing embryo. The enhancement in total B. microplus RNA was observed after cellularization, corroborating the replacement of maternal-driven processes by embryonic zygotic expression. An abrupt increase in oxygen consumption was observed from cellularization until the 8th day of development. The reduction in dry weight at the same period and the susceptibility of oxygen consumption to KCN suggest that the respiration process is activated during early embryonic development. A marked decrease in total lipid content occurred between the 5th and 7th days of development, suggesting this is the main energy source for cellularization. A major reduction in carbohydrate content occurred later, between the 7th and 9th days, and it could be assigned to the morphological segmentation of the embryo. Although the total amount of proteins remains unchanged from oviposition to hatching, a 15% reduction in vitellin (VT) content was observed before cellularization, up to the 4th day after egglaying. This observation was correlated to the synthesis of new proteins needed to support early embryo development. Additional 20% of VT was consumed thereafter, mainly at the end of embryogenesis, and in this case VT is probably used as energy source to the older embryo. Altogether, these data indicate different energy sources for maternal and zygotic driven processes. 相似文献
104.
Antinociceptive activity of the pyranocoumarin seselin in mice 总被引:1,自引:0,他引:1
Lima V Silva CB Mafezoli J Bezerra MM Moraes MO Mourão GS Silva JN Oliveira MC 《Fitoterapia》2006,77(7-8):574-578
Seselin an angular pyranocoumarin at dose of 0.5, 4.5 or 40.5 mg/kg inhibited the writhing response induced by acetic acid in a significant and dose-dependent manner, by 19.5%, 26.2% and 41.4%, respectively. Using the same doses, seselin elicited a significant inhibition of formalin response during the second phase (inflammatory), by 90.3%, 97.8% and 95.3%, respectively. Besides, a significant reduction of licking time was observed during the first phase (neurogenic) at the highest doses of seselin, by 34.4% and 66.9%, respectively. On the contrary, in the hot plate test no effect was observed after seselin treatment. In conclusion, seselin was able to inhibit inflammatory hyperalgesia, suggesting that this natural product possesses both important peripheral anti-inflammatory and antinociceptive properties. 相似文献
105.
Wanderley dos Santos Bruno Marchetti de Souza Daniele Fernanda Zulian Gilberto Terra Ribeiro Alves Jo 《林业研究》2022,33(1):309-319
Investment in silvicultural techniques is notice-ably lacking,especially in breeding programs for non-con-ventional wood species.Studying genotype × environment interaction (G × E) is essential to the development of breed-ing programs.Thus,this study aimed to estimate genetic diversity of and the effects of G × E interaction on two prog-eny tests of Cordia trichotoma,including the estimation of genetic gain and genetic diversity after selection.For the experiment,30 progenies of C.trichotoma were tested at two sites with differing soil textures.Diameter at breast height (1.30 m above soil surface,dbh-cm),total height,diameter at 30 cm from the soil,first branch height,and survival were all monitored for four years.Statistical devi-ance,best linear unbiased estimator,and harmonic mean of relative performance of genetic values (MHPRVG) were all calculated to predict breeding values,estimate genetic parameters,and analyze deviance.All quantified traits varied significantly among progenies by soil type,with greatest variation recorded for genetic variability.Heritability of the progenies led to predictions of genetic gain,ranging from 7.73 to 15.45%,for dbh at four years of age.The calculated decrease in genetic diversity after selection showed that this parameter should be monitored in subsequent breed-ing cycles.G × E was low for all tests.The best-performing progenies proved most stable and best adapted to the differ-ent environmental conditions tested. 相似文献
106.
107.
Carneiro Mario Davi Dias Maltez Lucas Campos Rodrigues Ricardo Vieira Planas Miquel Sampaio Luís André 《Fish physiology and biochemistry》2021,47(4):841-848
Fish Physiology and Biochemistry - The nitrification process in recirculating aquaculture systems can reduce water pH. Fish can also be exposed to water acidification during transport, an important... 相似文献
108.
Ligation of the caudal mesenteric artery during resection and anastomosis of the colorectal junction for annular adenocarcinoma in two dogs 总被引:1,自引:1,他引:0
An 8-year-old terrier cross and a 10-year-old German Shorthaired Pointer presented to the University Veterinary Centre, Sydney, for investigation of long-standing tenesmus and dyschezia. Both patients had an annular adenocarcinoma at the colorectal junction. Exploratory laparotomy was performed and the affected large intestinal segment was removed by resection and anastomosis. In both dogs, the caudal mesenteric artery was intimately associated with the mass, necessitating its ligation and transection. Postoperatively, there was no evidence of anastomosis breakdown in either case and both animals recovered well from surgery. The dogs were euthanased 8 and 10 months, respectively, after surgery because of clinical signs relating to metastatic disease. 相似文献
109.
Moraes ML Ribeiro AM Kessler AM Ledur VS Fischer MM Bockor L Cibulski SP Gava D 《Journal of animal science》2012,90(8):2590-2598
An experiment was conducted to evaluate the effect of CLA on the immune response and performance of piglets when subjected to an immune challenge. A total of 32 weanling pigs (17 to 23 d of age) with an initial BW of 8.9 kg were allotted to a 3 × 2 factorial arrangement of treatments. There were 3 levels of dietary CLA (0%, 1%, and 2%) and 2 levels of lipopolysaccharide (LPS) challenge (unchallenged and challenged). Challenged pigs were challenged on d 7 and 21. On d 4 and 18, all pigs were inoculated with BSA for assessment of IgG production. There was no difference in growth performance among piglets receiving different CLA supplementation levels. However, LPS-challenged piglets had poorer BW (P < 0.05), ADFI (P < 0.01), and ADG (P < 0.001) compared with the control group at d 35 postweaning. Lipopolysaccharide-challenged piglets also had increased respiratory rate (P < 0.001) and rectal temperature (P < 0.001), and decreased plasma proteins, hematocrit, and white blood cell counts (P < 0.05). Production of IgG against BSA was increased in the 1% CLA supplementation group (P < 0.001), indicating that CLA has an immunomodulatory effect. Supplementation with CLA did not affect lymphocyte proliferation, percentage of CD4(+) and CD8(+) cells, plasma proteins, red and white blood cell count, respiratory rate, or rectal temperature after LPS challenge. Although CLA supplementation did not influence growth performance or certain immune system measurements, the increased IgG titers with 1% CLA dietary supplementation indicate that it has a beneficial effect on the humoral immune system of weaned piglets. 相似文献
110.
JR Delaney DS Kelley MD Lilley DA Butterfield JA Baross WSD Wilcock RW Embley M Summit 《Science (New York, N.Y.)》1998,281(5374):222-230
Seafloor diking-eruptive events represent the irreducible, quantum events of upper oceanic crustal accretion. They record events by which a large portion of the oceanic crust has formed through geological history. Since 1993, the U.S. Navy's real-time Sound Surveillance System has allowed location of ongoing acoustic signatures of dike emplacement and basalt eruptions at ridge crests in the northeast Pacific. These diking-eruptive events trigger a sequence of related, rapidly evolving physical, chemical, and biological processes. Magmatic volatiles released during these events may provide nutrients for communities of subseafloor microorganisms, some of which thrive in high-temperature anaerobic environments. Many of the organisms identified from these systems are Archaea. If microorganisms can thrive in the water-saturated pores and cracks within deep, volcanically active portions of our planet, other hydrothermally active planets may harbor similar life forms. 相似文献