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排序方式: 共有486条查询结果,搜索用时 15 毫秒
481.
Donnelly JJ Barnett SW Dorenbaum A Stamatatos L 《Science (New York, N.Y.)》2002,297(5585):1277-8; author reply 1277-8
482.
Pablo Campos Jose L. Oviedo Alejandro Caparrós Lynn Huntsinger Inocencio Coelho 《Strength and Conditioning Journal》2009,62(3):240-252
Most of the Mediterranean woodlands in Spain, Portugal, and California are managed as agrosilvopastoral enterprises, producing some combination of livestock, wood, cork products, and crops, as well as wildlife habitat and diverse environmental services. Private amenity benefits to landowners have been suggested as an explanation for high land prices and the persistence of such rangeland enterprises despite apparently marginal cash returns. In this study, private amenity values are estimated using a contingent valuation technique in surveys of private woodland owners as part of five case studies, using a design developed to separate landowner amenity income and capital values. Nonindustrial private landowners were asked about the maximum amount of money that they were willing to give up (to pay) before selling their property to invest in more commercially profitable assets, and the proportion of the market price of their woodland that they think is explained by privately consumed amenities. Amenity values were found to be relevant because, in all cases, landowners were willing to pay &spigt; €120 · ha-1 · yr-1, at 2002 prices, and attributed &spigt; 30% of land market price to amenities. These values represent an amenity profitability rate &spigt; 2% in all case studies. The data analysis shows some similarities, but mostly divergences, in the different land-simulated and amenity-simulated markets. 相似文献
483.
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
484.
Luis Otavio Brito Luis Alejandro Vinatea Arana Roberta Borda Soares William Severi Rayzza Helena Miranda Suzianny Maria Bezerra Cabral da Silva Maria Raquel Moura Coimbra Alfredo Olivera Gálvez 《Aquaculture International》2014,22(5):1649-1664
A 28-day indoor trial was conducted to evaluate the water quality, phytoplankton composition and growth of Litopenaeus vannamei in an integrated biofloc system with Gracilaria birdiae and Gracilaria domingensis. The experimental design was completely randomized with three treatments: control (shrimp monoculture); SB (shrimp and G. birdiae) and SD (shrimp and G. domingensis), all with three replicates. Random sampling was done (6 % of total population per experimental unit) to confirm white spot syndrome Virus (WSSV) infection using nested-PCR analysis due to suspicion of presence of the virus in the experiment (treatment and control groups). Shrimp L. vannamei (2.63 ± 0.10 g) were stocked in experimental tanks at a density of 425 shrimp m?3, and the Gracilaria was stocked at a biomass of 2.0 kg m?3. Shrimp mortality began in both the experimental and control groups at 10 days of culture. The integrated biofloc system (shrimp and seaweed) increased settleable solids (by 26–52 %); final weight (by 6–21 %); weekly growth (by 17–43 %); weight gain (by 17–43 %); specific growth rate (by 16–36 %); and yield (by 5–7 %) and decreased feed conversion ratio (by 21–28 %) and Cyanobacteria density about 16 % as compared to the control (shrimp monoculture). The use of red seaweed Gracilaria in an integrated biofloc system can enhance shrimp growth and reduce Cyanobacteria density in the presence of WSSV. 相似文献
485.
Volk HA Matiasek LA Luján Feliu-Pascual A Platt SR Chandler KE 《Veterinary journal (London, England : 1997)》2008,176(3):310-319
Twenty-two dogs with idiopathic epilepsy which were pharmacoresistant to phenobarbitone and bromide were treated with levetiracetam as an add-on medication. Records of eight dogs were used retrospectively to determine a safe, efficient levetiracetam dosage. Fourteen dogs were entered into a prospective, open label, non-comparative study. After 2 months of levetiracetam oral treatment (10 mg/kg TID), 8/14 dogs responded significantly to the treatment and seizure frequency was reduced by 50%. In dogs that remained refractory, the dosage was increased to 20 mg/kg TID for 2 months. One further dog responded to levetiracetam treatment. Levetiracetam responders had a significant decrease in seizure frequency of 77% (7.9+/-5.2 to 1.8+/-1.7 seizures/month) and a decrease in seizure days per month of 68% (3.8+/-1.7 to 1.2+/-1.1 seizure days/month). However, 6/9 responders experienced an increase in seizure frequency and seizure days after 4-8 months continuing with the levetiracetam treatment at the last effective dosage. Levetiracetam was well tolerated by all dogs and sedation was the only side-effect reported in just one of the 14 dogs. 相似文献
486.
Fabiola G. Valenzuela Que Gilberto Villanueva-López Alejandro Alcudia-Aguilar Ojilve Ramón Medrano-Pérez Luisa Cámara-Cabrales Pablo Martínez-Zurimendi Fernando Casanova-Lugo Deb Raj Aryal 《Soil Use and Management》2022,38(2):1237-1249
Silvopastoral systems have great potential for storing carbon because of carbon assimilation in tree woody biomass, carbon input through litterfall and below-ground carbon turnover. In this study, we quantified and compared the carbon stocks at livestock ranches in Tabasco, Mexico, containing either scattered trees in grazing pastures (STP) or grass monocultures. Sampling plots were randomly established at each ranch where the above- and below-ground carbon stocks, carbon input from litterfall, grass production and arboreal biomass growth were measured. We found that silvopastoral systems stored an average of 257.45 Mg ha−1 of soil organic carbon (SOC) compared to 119.17 Mg SOC ha−1 at grass monoculture ranches (to 30 cm depth); silvopastoral systems also stored 44.64 Mg C ha−1 in wood biomass; and, grass monocultures had greater cumulative grass biomass production. Overall, it is concluded that livestock ranches in Tabasco, Mexico, with scattered trees in grazing pastures stored 58.8% more carbon than those grass monocultures, with carbon stocks of 327.01 Mg C ha−1and 134.47 Mg C ha−1, respectively. The results are useful for land management decision making for sustainable livestock systems framed in the Sustainable Development Goals (SDGs). 相似文献