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排序方式: 共有588条查询结果,搜索用时 15 毫秒
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Nathaly Enciso Luciana L. K. Ostronoff Guillermo Mejías Leticia G. León María Luisa Fermín Elena Merino Cristina Fragio Luis Avedillo Concepción Tejero 《Veterinary research communications》2018,42(1):29-38
Adult Mesenchymal Stem Cells (MSC) are cells that can be defined as multipotent cells able to differentiate into diverse lineages, under appropriate conditions. These cells have been widely used in regenerative medicine, both in preclinical and clinical settings. Initially discovered in bone marrow, MSC can now be isolated from a wide spectrum of adult and foetal tissues. Studies to evaluate the therapeutic potential of these cells are based on their ability to arrive to damaged tissues. In this paper we have done a comparative study analyzing proliferation, surface markers and OCT4, SOX9, RUNX2, PPARG genes expression in MSC cells from Bone marrow (BMMSC) and Adipose tissue (ASC). We also analyzed the role of Stem Cell Factor (SCF) on MSC proliferation and on ASCs metalloproteinases MMP-2, MMP-9 secretion. Healthy dogs were used as BMMSC donors, and ASC were collected from omentum during elective ovariohysterectomy surgery. Both cell types were cultured in IMDM medium with or without SCF, 10% Dog Serum (DS), and incubated at 38 °C with 5% CO2. Growth of BMMSCs and ASCs was exponential until 25–30 days. Flow citometry of MSCs revealed positive results for CD90 and negative for CD34, CD45 and MCH-II. Genes were evaluated by RT-PCR and metalloproteinases by zymografy. Our findings indicate morphological and immunological similarities as well as expression of genes from both origins on analyzed cells. Furthermore, SCF did not affect proliferation of MSCs, however it up-regulated MMP-2 and MMP-9 secretion in ASCs. These results suggest that metalloproteinases are possibly essential molecules pivoting migration. 相似文献
3.
Evaluating the nutritive profile of three insect meals and their effects to replace soya bean in broiler diet
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S. Khan R. U. Khan W. Alam A. Sultan 《Journal of animal physiology and animal nutrition》2018,102(2):e662-e668
This study was conducted to evaluate the comparative effect of maggot meal, silkworm meal and mealworm as dietary protein source on the production performance and some aspects of meat quality in broilers. In this regard, maggot meal was reared on chicken offal and poultry waste. Silkworm meal was obtained from silk industry, while mealworm was developed through beetles rearing. A total of 120‐day‐old broiler chicks were randomly divided into four groups where soya bean meal (M0) was replaced with maggot meal (M1), silkworm meal (M2) and mealworm (M3) respectively. Each group was further divided into three replicates. The study was carried out for a period of 5 weeks. Diets containing mealworm significantly reduced overall feed consumption and resulted into higher weight gain (p < .05). Lowest feed conversion ratio (FCR) was recorded for birds fed with mealworm diet (p < .05). Tenderness and juiciness of meat were higher (p < .05) in M3 compared to the control and other treatments. Mortality did not vary between the control and the treated groups. Therefore, it is concluded that insect meal is rich in essential nutrients and could be successfully used in broiler ration without compromising acceptability. In the light of this study, mealworm is the best choice in broiler ration, in comparison with maggot and silkworm. 相似文献
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Inmaculada Riba Enrique García-Luque Alejandra Maz-Courrau María Luisa González de Canales Tomás Ángel DelValls 《Water, air, and soil pollution》2010,212(1-4):329-336
This study assesses the effect of salinity in bioavailability and toxicity of Zn by means of laboratory bioassays by observing contamination in both sediment and water, accumulation of Zn in biological tissues, and histopathological damage in the gills and guts tissues of Ruditapes philippinarum clams, which were exposed to different types of sediments from the Gulf of Cádiz (SW Spain) as well as two dilutions of toxic mud coming from an accidental mining spill. With this objective, the coefficients of distribution (K D) for Zn between overlying water and sediments were calculated, the histopathological frequencies in the tissues of the gills and guts of clams were determined, and the biota-sediment bioaccumulation factors as well as the bioaccumulation factors were quantified in the different stations. Results showed that the greatest histopathological damages appeared when the salinity values decreased. Statistical results showed that salinity was inversely correlated with histopathological damage (p?<?0.01) for the lesion index for gills. The most outstanding results were observed in the two dilutions of toxic mud (0.3% and 7.9%) at a salinity value of 10. Salinity was inversely correlated with the concentration of Zn in biological tissues (p?<?0.05) and inversely correlated with the concentration of Zn in water and sediment. Zn mobilization to the overlying water is produced when salinity values decrease. 相似文献
6.
Yousef S. Al-Hafedh Aftab Alam Mohamed Salaheldin Beltagi 《Journal of the World Aquaculture Society》2008,39(4):510-520
An indoor aquaponic system (i.e., the integration of fish culture with hydroponic plant production in a recirculating setup) was operated for maximizing water reuse and year-round intensive food production (Nile tilapia, Oreochromis niloticus , and leaf lettuce) at different fish feed to plants ratios. The system consisted of a fish culture component, solid removal component, and hydroponic component comprising six long channels with floating styrofoam rafts for holding plants. Fish culture effluents flowed by gravity from the fish culture component to the solid removal component and then to the hydroponic component. Effluents were collected in a sump from which a 1-horsepower in-line pump recirculated the water back to the fish culture tanks at a rate of about 250 L/min. The hydroponic component performed as biofilter and effectively managed the water quality. Fish production was staggered to harvest one of the four fish tanks at regular intervals when fish attained a minimum weight of 250 g. Out of the total eight harvests in 13 mo, net fish production per harvest averaged 33.5 kg/m3 of water with an overall water consumption of 320 L/kg of fish produced along with the production of leaf lettuce at 42 heads/m2 of hydroponic surface area. Only 1.4% of the total system water was added daily to compensate the evaporation and transpiration losses. A ratio of 56 g fish feed/m2 of hydroponic surface effectively controlled nutrient buildup in the effluents. However, plant density could be decreased from 42 to 25–30 plants/m2 to produce a better quality lettuce. 相似文献
7.
FDI in Space Revisited: The Role of Spillovers on Foreign Direct Investment within the European Union
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Luisa Alamá‐Sabater Benedikt Heid Eduardo Jiménez‐Fernández Laura Márquez‐Ramos 《Growth and change》2017,48(3):390-408
We estimate a spatial econometric interaction model for bilateral aggregate FDI stock data between 25 European Union member countries in 2010. We find evidence for spatial spillovers of foreign direct investment for three different types of spatial dependence. Our results document FDI spillovers between neighboring countries of FDI origin countries, neighboring countries of FDI destination countries as well as between neighboring countries of both FDI origin and destination countries. Relying on recently developed methods, we provide the first model‐consistent interpretation of marginal effects of market size (measured by GDP) as well as GDP per capita on bilateral FDI activity. Our research highlights the importance of taking into account spatial lags when estimating bilateral FDI gravity models. 相似文献
8.
Phytate degradation by lactic acid bacteria and yeasts during the wholemeal dough fermentation: a 31P NMR study 总被引:1,自引:0,他引:1
Reale A Mannina L Tremonte P Sobolev AP Succi M Sorrentino E Coppola R 《Journal of agricultural and food chemistry》2004,52(20):6300-6305
myo-Inositol hexaphosphate (IP6) is the main source of phosphorus in cereal grains, and therefore, in bakery products. Different microorganisms such as yeasts and lactic acid bacteria have phytase enzymes able to hydrolyze IP6 during the wholemeal breadmaking. In this paper, the phytase activity of Lactobacillus plantarum, Lactobacillus brevis, Lactobacillus curvatus, and Saccharomyces cerevisiae strains, isolated from southern Italian sourdoughs, is assayed using the (31)P NMR technique. The sourdough technology based on the use of lactic acid bacteria in the breadmaking is finally suggested. 相似文献
9.
Cruciferous oilseeds are important sources of oil, proteins, and glucosinolates (GLs), potentially available when biorefinery processes are used. The proposed extraction technology is based on the use of reverse micelles (RMs) made with cetyltrimethylammonium bromide (CTAB) dispersed in organic solvent. The physicochemical properties of this extraction system and the good water solubility of many high value compounds, such as GLs and some proteins, permit the simultaneous extraction of oil, and these products from cruciferous oilseed meals. This procedure is based on three main steps: (i) seed conditioning; (ii) solid-liquid extraction by RM solution; and (iii) back-transfer of the RM solution for recovery of the extracted compounds. The method makes it possible to simultaneously extract almost the same amount of oil as with pure organic solvents used in the current extraction plants and more than 90% of soluble proteins and GLs. It is a promising biorefinery technology alternative to traditional oil extraction processes. 相似文献
10.
Blanch Gracia Patricia Gómez-Jiménez Maria C. del Castillo Maria Luisa Ruiz 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(2):177-183
Plant Foods for Human Nutrition - Grapes contain high contents of phenolics, which are known to possess health promoting properties. Exogenous application of phytoregulators, mainly methyl... 相似文献