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排序方式: 共有220条查询结果,搜索用时 31 毫秒
211.
Miguel Angel ANGEL Maria Antonia GIL Cristina CUELLO Jonatan SANCHEZ-OSORIO Jesus GOMIS Inmaculada PARRILLA Jordi VILA Ignacio COLINA Marta DIAZ Josep REIXACH Jose Luis VAZQUEZ Juan Maria VAZQUEZ Jordi ROCA Emilio A. MARTINEZ 《The Journal of reproduction and development》2014,60(5):371-376
This study aimed to evaluate the effect of recipient-donor estrous cycle synchrony on recipient reproductive performance
after nonsurgical deep-uterine (NsDU) embryo transfer (ET). The transfers (N=132) were conducted in recipients sows that
started estrus 24 h before (–24 h; N=9) or 0 h (synchronous; N=31), 24 h (+24 h; N=74) or 48 h (+48 h; N=18) after the
donors. A total of 30 day 5 morulae or day 6 blastocysts (day 0=onset of estrus) were transferred per recipient. The highest
farrowing rates (FRs) were achieved when estrus appeared in recipients 24 h later than that in the donors (81.1%), regardless
of the embryonic stage used for the transfers. The FR notably decreased (P<0.05) when recipients were –24 h asynchronous
(0%), synchronous (61.3%) or +48 h asynchronous (50%) relative to the donors. No differences in litter size (LS) and piglet
birth weights were observed among the synchronous and +24 h or +48 h asynchronous groups. While a +24 h asynchronous
recipient was suitable for transfers performed with either morulae (FR, 74.3%; LS, 9.2 ± 0.6 piglets) or blastocysts (FR,
84.6%; LS, 9.8 ± 0.6 piglets), a + 48 h asynchronous recipient was adequate for blastocysts (FR, 87.5%; LS, 10.4 ± 0.7
piglets) but not for morulae (FR, 30.0%; LS, 7.3 ± 2.3 piglets). In conclusion, this study confirms the effectiveness of the
NsDU-ET technology and shows that porcine embryos tolerate better a less advanced uterine environment if they are
nonsurgically transferred deep into the uterine horn. 相似文献
212.
Modeling spatial distribution of European badger in arid landscapes: an ecosystem functioning approach 总被引:1,自引:1,他引:0
Juan M. Requena-Mullor Enrique López Antonio J. Castro Javier Cabello Emilio Virgós Emilio González-Miras Hermelindo Castro 《Landscape Ecology》2014,29(5):843-855
Understanding the factors determining the spatial distribution of species is a major challenge in ecology and conservation. This study tests the use of ecosystem functioning variables, derived from satellite imagery data, to explore their potential use in modeling the distribution of the European badger in Mediterranean arid environments. We found that the performance of distribution models was enhanced by the inclusion of variables derived from the Enhanced Vegetation Index (EVI), such as mean EVI (a proxy for primary production), the coefficient of variation of mean EVI (an indicator of seasonality), and the standard deviation of mean EVI (representing spatial heterogeneity of primary production). We also found that distributions predicted by remote sensing data were consistent with the ecological preferences of badger in those environments, which may be explained by the link between EVI-derived variables and the spatial and temporal variability of food resource availability. In conclusion, we suggest the incorporation of variables associated with ecosystem function into species modeling exercises as a useful tool for improving decision-making related to wildlife conservation and management. 相似文献
213.
Canedoli Claudia Ficetola Gentile Francesco Corengia Davide Tognini Paola Ferrario Andrea Padoa-Schioppa Emilio 《Landscape Ecology》2022,37(1):347-365
Landscape Ecology - A landscape is defined as a “system of ecosystems” and this is a model in which karst areas can easily be integrated. In karst areas, much of the connectivity... 相似文献
214.
Emilio Galán Isabel González Antonio Romero Patricia Aparicio 《Journal of Soils and Sediments》2014,14(4):810-818
Purpose
The determination of the contribution of background values in a potentially polluted soil is very important in defining the contamination extension, in particular in areas of geological complexity and long-term economic development, where mining and industry have been traditional activities and soils are showing both geogenic and anthropogenic contributions. Some approaches have been proposed for the estimation of the anthropogenic input vs. the background; in this paper we present a more robust approach.Materials and methods
The proposed methodological approach includes the following steps. The first step consists of the comparison among the trace element contents in potentially polluted soils (PPS) and the reference and threshold values calculated both for the same geotectonic unit. A second stage is the calculation of the reference and threshold values for the surrounding area (LTV), natural setting, of the PPS with similar lithological characteristics. The final step is based on the analysis of the results by comparison of the PPS with LTV. On the other hand, the definition of a new pollution factor allows to grade the pollution and to classify the pollution importance.Results and discussion
The protocol proposed was applied to PPS from a potentially polluted area of SW Spain. The anthropogenic vs. geogenic anomalies and the pollution grade of the three PPS were assessed, which is important to establish the priority to further actions. In addition, this study makes clear that the use of the enrichment factors to estimate the pollution of soils is not advisable. On the other hand, in this study, new areas close to the PPS were defined as potentially polluted because of the high trace element concentration.Conclusions
The methodological approach proposed can be considered as a good indicator for evaluating the geogenic vs. anthropogenic contribution in polluted soils and for classifying the pollution importance in a more robust way than the use of other previous indexes. The proposal methodology could be used also by the administration to detect other PPS in a study area, which a priori were not considered as contaminated. 相似文献215.
Nisoli E Clementi E Paolucci C Cozzi V Tonello C Sciorati C Bracale R Valerio A Francolini M Moncada S Carruba MO 《Science (New York, N.Y.)》2003,299(5608):896-899
Nitric oxide was found to trigger mitochondrial biogenesis in cells as diverse as brown adipocytes and 3T3-L1, U937, and HeLa cells. This effect of nitric oxide was dependent on guanosine 3',5'-monophosphate (cGMP) and was mediated by the induction of peroxisome proliferator-activated receptor gamma coactivator 1alpha, a master regulator of mitochondrial biogenesis. Moreover, the mitochondrial biogenesis induced by exposure to cold was markedly reduced in brown adipose tissue of endothelial nitric oxide synthase null-mutant (eNOS-/-) mice, which had a reduced metabolic rate and accelerated weight gain as compared to wild-type mice. Thus, a nitric oxide-cGMP-dependent pathway controls mitochondrial biogenesis and body energy balance. 相似文献
216.
217.
Cárceles CM Escudero E Fernández-Varón E Marín P 《Veterinary journal (London, England : 1997)》2009,180(3):343-347
The disposition kinetics of moxifloxacin, a fluoroquinolone antibiotic, after intravenous (IV), intramuscular (IM) and subcutaneous (SC) administration was determined in sheep at a single dose of 5 mg/kg. The concentration-time data were analysed by compartmental (after IV dose) and non-compartmental (after IV, IM and SC administration) pharmacokinetic methods. Plasma concentrations of moxifloxacin were determined by high performance liquid chromatography with fluorescence detection. Steady-state volume of distribution (Vss) and clearance (Cl) of moxifloxacin after IV administration were 2.03 ± 0.36 L/kg and 0.39 ± 0.04 L/h kg, respectively. Following IM and SC administration, moxifloxacin achieved maximum plasma concentration of 1.66 ± 0.62 mg/L and 0.90 ± 0.19 mg/L at 2.25 ± 0.88 h and 3.25 ± 1.17 h, respectively. The absolute bioavailabilities after IM and SC routes were 96.12 ± 32.70% and 102.20 ± 23.76%, respectively. From these data (kinetic parameters and absence of adverse reactions) moxifloxacin may be a potentially useful antibiotic in sheep. 相似文献
218.
219.
Emilio F. Rodrigues Jr Alexandre P. Ribeiro Eduardo Perlmann† Dennis E. Brooks‡ José Luiz Laus 《Veterinary ophthalmology》2009,12(4):254-258
Chondrosarcoma accounts for about 10% of all canine bone tumors and is the second most common primary bone tumor in dogs. In veterinary medicine, chondrosarcomas are classified as skeletal and extraskeletal. Extraskeletal chondrosarcomas are mesenchymal neoplasms of soft tissues and visceral organs that produce neoplastic chondrocytes in a fibrillary matrix. There is no involvement of bone or periosteal tissues in extraskeletal chondrosarcomas. The aim of this report is to describe the first case of a metastatic intraocular extraskeletal chondrosarcoma in a dog. 相似文献
220.
Hernández A Aranda E Martín A Benito MJ Bartolomé T de Gúa Córdoba M 《Journal of agricultural and food chemistry》2010,58(22):11688-11694
The purpose of this work was to develop a PCR method for the identification of smoked paprika "Pimento?n de la Vera" adulteration with paprika elaborated from varieties of pepper foreign to the la Vera region, in central western Spain. Three autochthonous varieties of pepper, Jaranda, Jariza, and Bola, and the varieties Papri Queen, Papri King, Sonora, PS9794, and Papri Ace, foreign to the La Vera region, were used in the study. Analyses of the ITS and 5.8S rDNA, RAPD-PCR, SSR, and ISSR were tested. RAPD-PCR, SSR, and ISSR analyses allowed differentiation among the varieties of paprika analyzed. There was no difference in the sequence of ITS1-5.8S rDNA-ITS2. In addition, with the RAPD-PCR primers S13 and S22, two molecular markers were obtained of 641 and 704 bp, respectively, which allowed all of the smoked paprika varieties to be differentiated from paprikas elaborated with the five foreign varieties. These two molecular markers were investigated as a basis for detecting the adulteration of smoked paprika with paprika elaborated from foreign varieties of pepper. 相似文献