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51.
The relationship between dental morphology, sex, body length and age of small cetaceans can be used to determine ontogeny, sexual dimorphism and geographical variation. The objective of this study was to determine the relationship between dental morphology, sex, body size and age. A total of 91 specimens of P. blainvillei and 80 specimens of S. fluviatilis accidentally captured in fisheries or stranded in northern Rio de Janeiro (21 masculine37'-22 masculine25'S), from September 1988 to November 1996 were analysed. The teeth root diameter in P. blainvillei was significantly different between the sex; the values for females were larger than males. In neither species aid we observed significant in variations dimension and number of teeth, thickness of dentine and cemental layers and in the maximum width of cement as a function of body size. Age was related to increases in tooth length, root and cingulum diameters, and maximum width of cement in individuals of P. blainvillei, and tooth and crown lengths and maximum width of cement in individuals of S. fluviatilis. The observation of a linear growth between maximum width of cement and age in both species indicates that the equations obtained can be used to estimate relative age in P. blainvillei and S. fluviatilis in northern of Rio de Janeiro. 相似文献
52.
The ability of two strains of Lactobacillus acidophilus, CRL 640 and CRL 800, to survive and retain their biological activities under frozen storage was determined. Freezing and thawing, as well as frozen storage, damaged the cell membrane, rendering the microorganisms sensitive to sodium chloride and bile salts. Both lactic acid production and proteolytic activity were depressed after 21 days at -20 degreesC, whereas beta-galactosidase activity per cell unit was increased. Cell injury was partially overcome after repair in a salt-rich medium. Copyright 1998 Academic Press. 相似文献
53.
Simulations show that for a certain range of its free parameters, a model of the immune network including both cellular and humoral components is capable of self-sustained oscillations. The model also possesses a number of fixed points which appear to be unstable. These results, taken together, suggest the hypothesis that the immune network may be able to sustain a non-degenerate diversity of active clones which are actively connected to each other only on condition that the activities of these clones are oscillatory. 相似文献
54.
55.
Aurigena Antunes de Araújo Hugo Varela Caroline Addison Carvalho Xavier de Medeiros Gerly Anne de Castro Brito Kênio Costa de Lima Ligia Moreno de Moura Raimundo Fernandes de Araújo Júnior 《PloS one》2015,10(2)
Oral mucositis (OM) is a common complication of treatments for head and neck cancer, particularly radiotherapy with or without chemotherapy. OM is characterised by oral erythema, ulceration, and pain. The aim of this study was to evaluate the effect of azilsartan (AZT), an angiotensin II receptor antagonist, on 5-fluorouracil (5-FU)-induced oral mucositis (OM) in Syrian hamsters. OM was induced by the intraperitoneal administration of 5-FU on experimental days 1 (60mg/Kg) and 2 (40mg/Kg). Animals were pretreated with oral AZT (1, 5, or 10 mg/kg) or vehicle 30 min before 5-FU injection and daily until day 10. Experimental treatment protocols were approved by the Animal Ethics Committee Use/CEUA (Number 28/2012) of the UFRN. Macroscopic analysis and cheek pouch samples were removed for histopathologic analysis. Myeloperoxidase (MPO), Malonyldialdehyde (MDA), interleukin-1 beta (IL-1β), interleukin-10 (IL-10), and tumour necrosis factor-alpha (TNF-α) were analysed by Enzyme Linked Immuno Sorbent Assay (ELISA). Vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), keratinocyte growth factor (KGF), and transforming growth factor (TGF)-α were measured by immunohistochemistry. Analysis of variance followed by Bonferroni’s test was used to calculate the means of intergroup differences (p ≤ 0.05). Treatment with 1 mg/kg AZT reduced levels MPO (p<0.01), MDA (p<0.5) and histological inflammatory cell infiltration, and increased the presence of granulation tissue. AZT treatment at 1 mg/kg reduced the TNF-α (p<0.05) and IL-1β (p<0.05) levels, increased the cheek pouch levels of IL-10 (p<0.01), and upregulated VEGF, FGF, KGF, and TGF-α. Administration of AZT at higher doses (5 and 10 mg/kg) did not significantly reverse the OM. AZT at a dose of 1 mg/kg prevented the mucosal damage and inflammation associated with 5-FU-induced OM, increasing granulation and tissue repair. 相似文献
56.
Ana T. Varela Anabela M. Simões João S. Teodoro Filipe V. Duarte Ana P. Gomes Carlos M. Palmeira Anabela P. Rolo 《Mitochondrion》2010,10(5):456-463
Indirubin-3′-oxime is an indirubin analogue that shows favorable inhibitory activity targeting glycogen synthase kinase 3β (GSK-3β). In this study, we evaluated if acute treatment with indirubin-3′-oxime (Ind) prevents hepatic ischemia/reperfusion (I/R) damage. Wistar rats were subjected to 150 min of 70% warm ischemia and 16 h of reperfusion. In the treated group 1 μM indirubin-3′-oxime was administered in the hepatic artery 30 min before ischemia. Acute treatment with Ind decreased serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) levels, comparatively to I/R livers. Bax translocation to the mitochondria and cytochrome c release were higher in I/R livers. Ind treatment significantly attenuated Bax translocation and preserved mitochondrial cytochrome c content. Ind also protected mitochondria from calcium-induced mitochondrial permeability transition (MPT), as well as the decrease in state 3 mitochondrial respiration, the delay in the repolarization after a phosphorylative cycle and the decrease in ATP content caused by I/R. By addressing GSK-3β activity and phosphorylated GSK-3β at Ser9 content in liver homogenates and isolated mitochondria, data suggests that inhibition of GSK-3β by indirubin-3′-oxime prevents the increase in mitochondrial phosphorylated GSK-3β at Ser9 induced by I/R, thus correlating with MPT inhibition and preservation of cytochrome c content. Pre-treatment with indirubin-3′-oxime in conditions of hepatic I/R, protects the liver by maintaining mitochondrial function and hepatic energetic balance. 相似文献
57.
The endocrine system may be the target of different types of trauma with varied consequences. The present article discusses trauma of the hypothalamic–pituitary axes, adrenal glands, gonads, and pancreas. In addition to changes in circulating hormone levels due to direct injury to these structures, there may be an endocrine response in the context of the stress caused by the trauma. 相似文献
58.
Peña Messina E Tapia Varela R Velázquez Abunader JI Orbe Mendoza AA Velazco Arce JM 《Revista de biología tropical》2010,58(4):1577-1586
Tilapia production has increased in Aguamilpa Reservoir, in Nayarit, Mexico, in the last few years and represents a good economic activity for rural communities and the country. We determined growth parameters, mortality and reproductive aspects for 2413 specimens of blue tilapia Oreochromis aureus in this reservoir. Samples were taken monthly from July 2000 through June 2001, of which 1 371 were males and 1 042 were females. Standard length (SL) and total weight (TW) were measured in each organism. The SL/TW relationships through power models for sexes were determined. The growth parameters L infinity k, and t0 of the von Bertalanffy equation were estimated using frequency distribution of length through ELEFAN-I computer program. Finally the reproductive cycle and size of first maturity were established using morph chromatic maturity scale. The results suggested that the males and females had negative allometric growth (b < 3). Significant differences were found between SL/TW model for the sexes, suggesting separate models for males and females. Results indicate that there are no differences in growth rates between sexes; the proposed parameters were L infinity = 43.33 cm standard length, k = 0.36/year and t0 = -0.43 years. Natural and fishing mortality coefficients were 0.83/year and 1.10/year, respectively. The estimated exploitation rate (0.57/year) suggested that during the study period the fishery showed signs of overfishing. Blue tilapia reproduces year-round; the highest activity occurs from January through May and size of first maturity was 23 cm SL. We conclude that it is necessary to establish a minimum catch size in this reservoir based on the reproductive behavior of this species. 相似文献
59.
Varela Eduardo Sousa; Beasley Colin Robert; Schneider Horacio; Sampaio Iracilda; Marques-Silva Nelane Do Socorro; Tagliaro Claudia Helena 《Journal of Molluscan Studies》2007,73(3):229-234
As a result of phenotypic plasticity, the cupped oysters (Crassostrea)are difficult to identify by means of their morphology. However,molecular DNA markers are a useful means of discriminating amongthese species. Cupped oysters are one of the most widely culturedmarine invertebrates and correct species identification is importantin aquaculture. Moreover, the molecular phylogeny of the genusCrassostrea and the subfamily Crassostreinae is still not clear.In order to identify the Brazilian cupped oysters and to clarifythe phylogenetic relationships of these species, we sequenceda fragment of mitochondrial DNA (16S rRNA gene) from 120 specimenscollected at nine different sites distributed along the Braziliancoast. The results identified two native species of oyster:Crassostrea gasar, from the Amazon to the Parnaíba delta;and Crassostrea rhizophorae, from the northeast (Fortim) tothe south of Brazil. An exotic Crassostrea species, closelyrelated to Indo-Pacific Crassostrea, was found in one locationin the north of Brazil. Crassostrea showed monophyly and theAtlantic oysters are clearly separated from the Indo-Pacificcluster. (Received 30 May 2006; accepted 12 April 2007) 相似文献
60.
J A Balsa C Varela T Lucas J García-Uría B Barceló J M Sancho-Rof 《Hormones et métabolisme》2002,34(8):435-440
In this study, we have investigated the effect of combined treatment using two somatostatin analogs, lanreotide or octreotide, with bromocriptine on GH release in cultures of GH-secreting pituitary tumors. Sixteen acromegalic patients were included in the study. All patients had been treated with lanreotide prior to the surgery. Five patients (31.2 %) reached GH levels below 2.0 microg/l and normal IGF-I levels according to age and sex after lanreotide treatment. A positive correlation was observed between the lanreotide-induced inhibition of GH release in vitro and serum GH decrease after lanreotide treatment (r = 0.52; p = 0.03). Combined treatment significantly inhibited GH release in vitro in 8 of the 16 tumors (50 %). However, only 5 (31.2 %) of the respective patients had been resistant to presurgical treatment with lanreotide. Three of these 5 patients (18.7 %) responded to a BC concentration similar to that achieved with therapeutic doses, and in 2 patients only when a pharmacological dose of BC was used in the combined treatment. The additive effect was observed with the combination of lanreotide and BC in 6 tumors and with octreotide and BC in 3. Only one tumor showed simultaneous response to both types of combination. These results suggest that the additive effect under the combined treatment might be found between 18 and 30 % of patients who are resistant to these drugs, and that different combinations of somatostatin analogs and dopamine agonists should be tested in resistant patients. 相似文献