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71.
Cátia Salvador M. Rosário Martins Henrique Vicente José Neves José M. Arteiro A. Teresa Caldeira 《Agroforestry Systems》2013,87(2):295-302
Wild edible mushrooms Amanita ponderosa Malençon and Heim are very appreciated in gastronomy, with high export potential. This species grows in some microclimates, namely in the southwest of the Iberian Peninsula. The results obtained demonstrate that A. ponderosa mushrooms showed different inorganic composition according to their habitat and the molecular data, obtained by M13-PCR, allowed to distinguish the mushrooms at species level and to differentiate the A. ponderosa strains according to their location. Taking into account, on the one hand, that the characterisation of different strains is essential in further commercialisation and certification process and, on the other hand, the molecular studies are quite time consuming and an expensive process, the development of formal models to predict the molecular profile based on inorganic composition comes to be something essential. In the present work, Artificial Neural Networks (ANNs) were used to solve this problem. The ANN selected to predict molecular profile based on inorganic composition has a 6-7-14 topology. A good match between the observed and predicted values was observed. The present findings are wide potential application and both health and economical benefits arise from this study. 相似文献
72.
Rosário Gonçalves Isabel Mariano Alejandro Núñez Sandra Branco Graham Fairfoul Robin Nicholas 《Veterinary journal (London, England : 1997)》2010,183(2):219-221
An outbreak of severe respiratory disease in a goat herd was associated with Mycoplasma ovipneumoniae, Mycoplasma arginini, Mannheimia haemolytica and Pasteurella multocida with mortality rates exceeding 20% in kids. Post mortem features in affected kids included severe pleuropneumonia, lung consolidation, large quantities of pleural fluid and pericarditis. This is the first report of atypical proliferative pneumonia in goats in Portugal. 相似文献
73.
Eva Pinho Mariana Henriques Rosário Oliveira Alberto Dias Graça Soares 《Fibers and Polymers》2010,11(2):271-276
The goal of this work was to create a new generation of greener fabrics made of natural materials. For that, resveratrol (Res),
obtained from Polygonum cuspidatum extract and known to have antibacterial, antifungal, and anti-inflammatory activity, was applied by an exhaustion method
to cotton, bamboo, and silk knit fabrics. The fabrics adsorption behavior was tested and the amount of Res adsorbed was determined
by its decrease on the immersion solutions with time and measured by spectrophotometry at 350 nm. The maximum adsorption capacity
was observed for silk and it was independent of pH conditions used (50.5 % at pH=7 and 58.3 % at pH=5 of the initial Res concentration).
At acidic pH conditions, cotton adsorbed 51.2 % of Res and Bamboo adsorbed only 28.1 % in 15 min. However, neither cotton
nor bamboo adsorbed Res at pH=7. The release behavior was also analyzed and the highest Res release was observed for cotton
in alkaline sweat and urine mimic solutions. The lowest release was achieved by cotton in water (1.0 ng/ml). Moreover, no relation was found between the amounts of Res adsorbed or released and cell viability. In conclusion, this
work shows that it is possible to obtain cotton, bamboo, and silk functionalized with resveratrol. The incorporating process
here described is simple and silk-Res can be presented as a good combination. 相似文献
74.
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76.
Gerard H. Ros Ellis Hoffland Erwin J.M. Temminghoff 《Soil biology & biochemistry》2009,41(6):1029-1039
Extractable Organic N (EON) or Dissolved Organic Nitrogen (DON) pools are often analyzed to predict N mineralisation, N leaching, and to evaluate agricultural (nutrient) management practices. Size and characteristics of both pools, however, are strongly influenced by methodology. Quantifying the influence of methodology can increase the accuracy of soil tests to predict N mineralisation, improve model simulations, and can help to quantify the contribution of the EON and DON pools to soil N cycling. We estimated the relative impact of methodological, management, and environmental factors on EON and DON, using a meta-analysis approach based on 127 studies. Our results indicate that the EON and DON pools are neither similar in size nor controlled by the same factors. The influence of factors controlling EON generally decreased in the order of methodology (Δ10-2400%), followed by environment (Δ11-270%) and management (Δ16-77%). DON concentrations were primarily controlled by management factors: different land use and fertilisation caused a variation of 37-118%. Seasonal variations in DON concentrations were generally smaller than variations in EON, suggesting that high mineralisation and sorption rates buffer DON. The large range in EON as affected by different methodology emphasizes the importance of using appropriate and standardized methods for the determination of EON. The determination of DON can be useful to estimate leaching losses. EON, however, can be used to assess the impact of soil management practices on the turnover rate of labile soil organic matter pools. 相似文献
77.
Ros Green T. David Waite Mike D. Melville Ben C. T. Macdonald 《Water, air, and soil pollution》2008,191(1-4):293-304
An open limestone channel (OLC) was constructed within an existing drain to treat the acidic and metal-rich drainage waters generated from an acid sulfate soil (ASS) catchment. The OLC was constructed downstream of a catchment pump and it consisted of a series of ponds and limestone sections. The accumulation of sediment over the limestone, preventing contact of limestone with acidic water, was the greatest problem impacting the OLC in its first year of operation. The continuous or sporadic operation of the catchment pump (at 120 l/s) was not sufficient to flush sediment from the limestone. The accumulation of large amounts of sediment onto the limestone reduced the amount of alkalinity and calcium released into solution. However, if the sediment is removed by agitating the limestone then an equivalent or greater amount of alkalinity may be added to solution and more metals removed from solution compared to fresh limestone. The coating on the limestone had a high concentration of manganese oxides in addition to slightly lower concentrations of aluminium and iron. Removal of these metals from the water was due to the increase in pH produced by limestone dissolution in addition to sorption reactions of the existing coating which had natural microbial activity. 相似文献
78.
Ros Green T. David Waite Mike D. Melville Ben C. T. Macdonald 《Water, air, and soil pollution》2008,191(1-4):319-330
The principles of limestone drain systems that are commonly used to passively remediate acid rock drainage have been adapted and modified for remediation of acidic and metal-rich drainage that is produced from broad scale agricultural land use of regions underlain by Acid Sulfate Soils (ASS). The acidic drainage water from sugar cane fields in an ASS catchment was collected from an open drain, filtered to reduce the transport of large particulates, and passed vertically through a polyethylene tank, which was filled with limestone aggregates (<75 mm). This Closed Tank Reactor (CTR) uses the principles of oxic and anoxic limestone drain systems that are designed to increase the partial pressure of carbon dioxide and thereby the alkalinity produced from the dissolution of limestone by metal-laden influent. During a non-continuous 70 day monitoring period, the discharge from the CTR had higher pH, lower acidity and lower metal concentrations compared to the inflow. Under average flow conditions (9 lpm), similar proportions of incoming dissolved aluminium and iron (61% and 56% respectively) were retained within the CTR. Two perforated pipes in the base of the CTR were used to flush precipitates from the system under rapid flow conditions (>50 lpm). The flushing was effective in removing approximately 10% of accumulated iron but only about 0.3% of accumulated aluminium from the CTR. Accumulation of aluminium inside the CTR is likely to present operational problems in attempts to apply such technology to many coastal acid sulfate soil drains. 相似文献
79.
Margarita Ros Carlos Garcia Maria Teresa Hernandez Alfredo Lacasa Pedro Fernandez Jose Antonio Pascual 《Biology and Fertility of Soils》2008,45(1):37-44
The Adenosine triphosphate (ATP) content, dehydrogenase, phosphatase, urease, and β-glucosidase activity decreased after manure
amendment plus solarization (biosolarization), but they recovered after cropping, reaching levels higher than or similar to
those before the biosolarization. However, these biochemical parameters decreased and did not recover with time in the methyl
bromide (MeBr) treatment. Potential negative soil effects were assayed by measuring, ecotoxicity (Vibrio fisheri luminescence), germination index, electrical conductivity, and heavy metals content. Biosolarization did not negatively affect
these parameters, while MeBr application irreversibly decreased the germination index and ecotoxicity. Higher-quality pepper
production (extra and first class) were observed with biosolarization but not with MeBr, but no differences were found for
pepper yield. Biosolarization gave a Meloidogyne incognita (M. incognita) incidence similar to that of MeBr application. 相似文献
80.
Frontela C Haro JF Ros G Martínez C 《Journal of agricultural and food chemistry》2008,56(10):3805-3811
Cereals are introduced to infants between the ages of 4 and 6 months to supplement breast milk and follow-on formula. Our objectives were to examine the content and in vitro availability of Fe, Ca, and Zn from five commercially available infant cereals mixed with water or follow-on formula before and after dephytinization. We estimated the bioaccessibility by measuring the soluble or dialyzable mineral fraction resulting from in vitro gastrointestinal digestion of the sample. For most infant cereals analyzed, dephytinization increased the in vitro availability of iron and zinc. This finding was especially dramatic among infant cereals mixed with follow-on formula rather than with water. However, the liquid used for reconstitution did not always show a significant (p < 0.05) interaction with phytase addition and in vitro mineral availability. The results of this study indicate that adding follow-on formula to infant cereals does not improve the bioaccessibility of iron, calcium, and zinc, despite the increase in mineral content it implies. Results obtained also showed that mineral solubility and dialyzability do not always follow parallel trends. 相似文献