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The toxicity of ochratoxin A (OTA), a mycotoxin produced by fungi ofAspergillus orPenicillium genera is now well documented. Its nephrotoxicity, immunosuppression, teratogenicity, and carcinogenicity have been widely studied. Physical and biochemical methods have been studied to prevent these toxinogenicAspergillus andPenicillium from producing OTA, and/or to destroy the mycotoxin when already produced in a liquid or a solid medium. Repeated freezing at ? 20?C and thawing at + 26?C aleatory reduce OTA production in a liquid medium. Exposure to UV B for different periods of time is efficient in preventing OTA production in a liquid medium. Gamma-irradiation from 2 to 5 kGy gives good results in preventing the production of OTA or destroying it when already produced. Carboxypeptidase is very efficient at 5 units/50 ml in a liquid medium for cleaving the OTA already produced.  相似文献   
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This study was undertaken to evaluate the relationship between concentrations of insulin and insulin-like growth factor I (IGF-I) in follicular fluid and fertilization and cleavage of human oocytes fertilized in vitro. The concentration of oestradiol, progesterone, luteinizing hormone, follicle-stimulating hormone, testosterone, insulin and IGF-I was determined in 36 follicular fluids, free of visible blood contamination and containing mature oocyte-corona-cumulus complexes, obtained from 12 women undergoing in vitro fertilization. Follicular development was induced by clomiphene citrate and human menopausal gonadotrophin, and follicular aspiration was performed 35 h after an ovulatory dose of human chorionic gonadotrophin. Concentrations of IGF-I were significantly higher in follicular fluids associated with mature oocytes that fertilized and cleaved, than in follicular fluid associated with mature oocytes that did not fertilize (P < 0.001). There was no difference in the concentration of insulin between follicular fluids from which fertilized oocytes were obtained and those with oocytes that remained unfertilized. No significant correlations were found between rates of embryo cleavage, concentrations of insulin and IGF-I. Multiple linear regression analysis demonstrated that the concentrations of IGF-I in follicular fluid were predicted statistically by a negative regression coefficient for the concentration of testosterone, and by a positive regression coefficient for the concentration of progesterone in follicular fluid. No candidate variable was included in the model to predict concentrations of insulin. These data suggest an important role for IGF-I in the mature follicle.  相似文献   
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The study is based on almost 10 million births and reports on 215 infants with two unusual malformations: amelia and gross body wall defect. Amelia without body wall defect was present in 116 cases, 67 had body wall defects without amelia, and 32 had both. The total rate was 2.2 per 100,000 births. The infants were divided into five mutually exclusive groups. There were 40 infants (0.4 per 100,000) with agenesis of the body stalk, 18 with amelia and other types of gross body wall defects (0.2 per 100,000), 56 with amelia and malformations other than gross body wall defects (0.6 per 100,000), 41 with amelia (with or without other limb reduction defects) but no nonlimb malformations (0.4 per 100,000), and 60 infants with gross body wall defects of a type other than agenesis of body stalk and without amelia (0.6 per 100,000). A weak trend of decreasing prevalence of these malformations was found during the observation period. Infants with agenesis of the body stalk and infants with amelia combined with other types of gross body wall defects occurred at an increased rate in infants of young women. This maternal age effect is also found with gastroschisis, but not with omphalocele, and may indicate etiological or pathogenetic similarities between gastroschisis and the two former groups of defect. In infants with amelia, additional limb reduction defects could be of any type: transverse, longitudinal, or intercalary. Therefore, amelia may be the end result of different types of disturbances of limb morphogenesis. There was an increased rate of twinning. The relationship with amniotic band syndrome is discussed.  相似文献   
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A method for perfusion of isolated canine tibia is described. With this procedure the influence of different albumins on the uptake of tritiated 25-hydroxyvitamin D3 (3H-25(OH)D3) by the tibia has been studied. Bovine serum albumin at 1% concentration seems to be optimum for this system. This experimental approach seems to be useful for the study of mineral metabolism.  相似文献   
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In northern Chile, Pyura praeputialis is an invasive species inhabiting rocky intertidal and subtidal habitats restricted exclusively to the Bay of Antofagasta where it forms extensive aggregations. The negative impact of Pyura gathering on mid‐intertidal abundances of this species has recently been reported at the south‐eastern end of this bay. In the present study we have increased sampling sites to cover the entire bay toward the north‐western end and the northern section, where a coastal marine reserve for the scallop fishery partially restricts shellfish gathering. Therefore, the sampling sites were chosen to represent different levels of shellfish gathering access along the northern shore of the bay. Long‐term monitoring (1999–2014) of changes in tunicate cover and the abundances of larvae and recruits at seven sites are reported. The opening of a remodelled artificial and recreational beach in 2012, on the central‐eastern shore of the bay, has increased accessibility to rocky intertidal platforms that started to be massively visited by Pyura gatherers from the summer of 2013. This allowed for the implementation of an intensive short‐term monitoring program of changes in tunicate cover and the abundances of their larvae and recruits. When gathering access was present the reduction in intertidal cover was generalized to the entire bay and followed by reductions in larvae and recruits. However, these reductions were not found in sites with more restricted gathering access. We conclude that continuous extraction by Pyura gatherers followed by reductions of conspecific larvae and recruits are the main drivers behind the reduced abundance of P. praeputialis in the entire bay of Antofagasta. Thus, if gathering is not stopped important ecosystem services provided by this tunicate in the bay may be threatened. Similar consequences may be expected if other massive and irreversible reductions in other species of the Pyura complex, that inhabit other coasts in the southern hemisphere, occur. The controversy concerning the impacts of invasive species and whether they cause negative, positive or neutral impacts to original ecosystems and fisheries is discussed.  相似文献   
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Aquaculture practices from sub-Saharan Africa are characterised by low production, owing to improper technology. Production can be increased through integrating fish farming with other existing on-farm activities, particularly livestock husbandry. We assessed the role of fish-poultry integration on all male Nile tilapia, Oreochromis niloticus growth performance, yields and economic benefits among smallholder farmers in sub-Saharan Africa, Tanzania. The study also compared phytoplankton species composition, abundance and biomass between the fish-poultry integration and non-integrated system. After 180 days of the experiment, all male O. niloticus cultured under fish-poultry integration exhibited significantly higher growth rates than those in the non-integrated system (p < 0.05). Gross fish yield (GFY), net fish yield (NFY) and net annual yields (NAY) obtained from fish-poultry integration were significantly higher than those from non-integrated system (p < 0.05). Partial enterprise budget analysis revealed that fish-poultry integration was more profitable than the non-integrated system. Moreover, fish-poultry integrated system produced significantly higher phytoplankton abundance and biomass than those from the non-integrated system. Results demonstrate that rural smallholder farmers can achieve higher growth rate, farm net yields and income by integrating all male O. niloticus with other on-farm activities than practising a stand-alone fish culture system.  相似文献   
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Recent studies demonstrated the importance of the mitochondrial ATP in the regulation of a novel long-chain fatty acid generation/export system in mitochondria of diabetic rat heart. In steroidogenic systems, mitochondrial ATP and intramitochondrial arachidonic acid (AA) generation are important for steroidogenesis. Here, we report that mitochondrial ATP is necessary for the generation and export of AA, steroid production and steroidogenic acute regulatory protein induction supported by cyclic 3'-5'-adenosine monophosphate in steroidogenic cells. These results demonstrate that ATP depletion affects AA export and provide new evidence of the existence of the fatty acid generation and export system involved in mitochondrial cholesterol transport.  相似文献   
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