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131.
Monomeric phenols, color and copigmentation parameters, pigments with different chemical structure, tannin, glucose, fructose, glycerol, ethanol, and organic acids were determined in DOC red wines from Marche (Italy), obtained during three different vintages ranging from 1996 to 2000. The intensity of the bitter and astringent tastes of the wines was determined with panel tastings. Lacrima di Morro and Vernaccia di Serrapetrona (obtained from local cultivars) were different from Rosso Piceno, Rosso Piceno Superiore, and Rosso Conero (produced from different percentages of Sangiovese and Montepulciano). Vernaccia, a red, sweet, "spumante" wine, was an outlier. Lacrima showed a low tannin content, a high content of small pigments and phenols, and a high ratio of copigmented color, which persisted after 3 years of aging. The chemical determinations accounted for a high percentage of variability of measured panel astringency, copigmented color, and measured wine absorbance at 520 nm. It was not possible to create a predictive model for bitterness.  相似文献   
132.
DEET (N,N-diethyl-meta-toluamide) is the world's most widely used topical insect repellent, with broad effectiveness against most insects. Its mechanism of action and molecular target remain unknown. Here, we show that DEET blocks electrophysiological responses of olfactory sensory neurons to attractive odors in Anopheles gambiae and Drosophila melanogaster. DEET inhibits behavioral attraction to food odors in Drosophila, and this inhibition requires the highly conserved olfactory co-receptor OR83b. DEET inhibits odor-evoked currents mediated by the insect odorant receptor complex, comprising a ligand-binding subunit and OR83b. We conclude that DEET masks host odor by inhibiting subsets of heteromeric insect odorant receptors that require the OR83b co-receptor. The identification of candidate molecular targets for the action of DEET may aid in the design of safer and more effective insect repellents.  相似文献   
133.
A survey has been carried out in three Regions of north-eastItaly, Emilia Romagna, Veneto and Friuli Venezia Giulia, withfour objectives: (a) to update the statistics on the use of pipedrainage; (b) to describe the farms that adopt this technique asa replacement of the traditional surface drainage methods;(c) to characterise the features of the drained soils and of thedrainage systems, and (d) to assess their performance. Withalmost 70.000 ha drained, the Regions present almost all of thepipe drained area in Italy. Pipe drainage first saw applicationsin the last seventies and became increasingly popular during theeighties. Most pipe drainage systems are installed in heavysoils, where the underground waterlogging is due to seasonalperched water table or to infiltrations from rivers or sea. Due tothe pedoclimatic variability of the area, slightly differentsolutions in terms of design variables and installation criteriaare found, but the following features are quite common: drainspacing 11–13 m slope 0.1–0.3%, depth 0.9–1 m. The pipe drains discharge in open collectors (single systems). Anincreasing interest for the use of the drainage systems forsubirrigation purposes has been observed, particularly inVeneto, requiring some adjustment in the drainage design. Theperformance of drainage in terms of control of water tabledepth and maintenance requirements are considered satisfactoryin almost all the cases. The most effective solutions forsuccessfully managing the subirrigation are also described.The introduction of pipe drains allows to enlarge fields (to morethan 10 has) and to save time for carrying out the operations forcrop cultivation. The crop yield in pipe drained fields is slightly higherto that obtained in the traditionally drained fields, withthe exception of winter wheat.  相似文献   
134.
Atriplex nummularia has been extensively planted in Northern Africa to combat desertification. However, few studies evaluated the effectiveness of these interventions. This study aimed at assessing the dynamic performance of a number of Atriplex plantations located in the Marrakech province in terms of multitemporal dry biomass production. Three SPOT 5 images (2004, 2008 and 2012) and field biomass measurements were integrated to quantify the dry biomass production dynamics of plantations established from 1996 to 2007. Different plant ages covered the whole plant life cycle curve. Vegetation indices were derived from the images and those of 2012 were coupled to the measured biomass of 2012 to formulate biomass models. An analysis of shrub biomass production was conducted in plantations and in adjacent rangelands, covering varying degree of plant development, and an estimate of the economic benefits generated by the plantations in terms of available fodder biomass was performed. The results show that, on average, the plantation sites produced 2·21 to 3·61 Mg ha−1 of dry biomass more than the surrounding rangelands. The best performing plantations yielded even greater differences, up to more than 7 Mg ha−1. It was observed that the most performing plantations, while contributing to mitigating land degradation, have generated economic value and could compensate the economic cost of the intervention even under drought conditions. However, in several cases the plantation performance was far from sustainability, particularly due to poor management (early and/or over grazing), revealing that management is a critical factor for the success of this restoration practice. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
135.
Summary In the 25-year-old vineyard of a farm near the Maremma National Park (Central Italy), replicate plots were established with a mulch of Trifolium subterraneum L. or cultivation and two levels of fertilizer. The mai objective of this research was to analyse responses by soil invertebrates and nutrients after introducing a herbaceous component into the system; the yield was also considered. The greater availability of organic substrate and the reduced cultivation as a result of green mulching increased the soil mesofauna biomass, especially detritivores. With time, a significant difference became evident between the populations of invertebrates present in the mulched plots and those in the cultivated plots. Over 2 years, most nutrients (Ca, K, P, and N) were significantly increased in the mulched plots compared to the cultivated plots. Grape yields were consistently higher in the bare plots. No significant differences were found in fertilizer effects.  相似文献   
136.
The aim of this study was to integrate hydrochemical and biological data in order to obtain a picture of the water quality along the River Lambro, considered to be one of the most polluted rivers in Italy. Biological sampling with artificial substrates was undertaken in February and May 1991 together with water sampling. Significant longitudinal variations between stations 1 and 2 were observed for temperature, conductivity and dissolved oxygen. Station 3 (Villanterio), situated on the southern tributary, showed a higher degree of pollution than the stations along the main course of the Lambro. E.B.I, and B.M.W.P. score gave a similar picture. A multivariate analysis (CCA) of the taxonomical and chemical data showed the greater influence of the environmental parameters conductivity and D.O. on the macroinvertebrate community structure. All the methods confirmed the strong impact of the Milan area on the river; two different environmental situations could be distinguished on the basis of characteristical groups of taxa. The artificial substrates combined with multivariate analysis proved to be a useful combination in the study of this river.  相似文献   
137.
The behaviour of Co, Fe, Mn, and Ni was investigated in the mixing area of the Po river in six surveys over the period March 1992 to June 1995 during low-to-medium solid load and flow conditions. The concentrations (nM) of dissolved elements for the riverine and marine end-members respectively were in the ranges 0.09 to 0.93 and 0.24 to 0.98 for Co, 10 to 53 and 5 to 20 for Ni, 12 to 87 and 5 to 33 for Fe, and 10 to 155 and 26 to 105 for Mn. Co and Mn behave non-conservatively in the Po estuary; an addition to the dissolved phase occurred for these elements that was more marked in the summer period. The concentrations of dissolved and particulate Ni decreased almost linearly with increase in salinity, with more marked variations in dissolved Ni concentration in winter than summer. The concentrations of dissolved and particulate Fe also varied conservatively with salinity. This unusual behaviour for dissolved Fe is attributed to the analytical procedure which excluded kinetically inert colloidal species.  相似文献   
138.
Melanins are very important pigments for the survival and longevity of fungi, so their biosynthesis inhibition is a new biochemical target aiming at the discovery of selective fungicides. In this work is described the synthesis of new pyrazolo-thiazolo-triazole compounds, analogues of tricyclazole (a commercial antifungal product that acts by inhibiting melanin synthesis), and their biological activity was studied on some dermatophytes and phytopathogens. The compounds poorly inhibited the growth and pigmentation of fungi tested and were less efficient than tricyclazole. Electron microscopy on Botrytis cinerea showed that treatment with the most active compound caused abnormally thickened and stratified walls in fungi, whose ultrastructure was, in contrast, generally normal. The fungus treated with tricyclazole, on the other hand, appeared to be drastically altered, so as to become completely disorganized. These results suggest that the new azole compounds employ an action mechanism similar to that of other azoles, but dissimilar to that of tricyclazole.  相似文献   
139.
Consumers are becoming increasingly aware of the relationship between food and health. Concerns have been raised about dietary fats and their relative nutritional advantages or disadvantages. In investigations of the associations between health and fat intake, special emphasis has been placed on the benefits of virgin olive oil for counteracting certain neurodegenerative diseases and ageing. With respect to ageing, accumulating evidence indicates that an improvement in quality of life can be reached by modulation of the extrinsic factors that influence many ageing processes. Of the modifiable factors, nutrition appears to be one of the strongest elements known to influence the rate of ageing as well as the incidence of age-associated diseases such as atherosclerosis and neurodegenerative pathologies. This paper reviews the theory of ageing and the role of fatty acids in the mechanisms affecting its evolution. It also confirms that virgin olive oil, an essential component of the Mediterranean diet, provides large amounts of stable and not easily oxidizable fatty acids as well as remarkable quantities of powerful antioxidant molecules.  相似文献   
140.
Pectin methylesterase was purified from kiwi (Actinidia chinensis) and kaki fruit (Diospyros kaki). The pH values of the fruit homogenates were 3.5 and 6.2, respectively. The kiwi enzyme is localized in the cell wall and has a neutral-alkaline pI, whereas the kaki enzyme is localized in the soluble fraction and has a neutral-acidic pI. The molecular weights of the kiwi and kaki enzymes were 50 and 37 kDa, respectively. The two enzymes showed a similar salt and pH dependence of activity, and a different pH dependence of the inhibition by the kiwi proteinaceous inhibitor.  相似文献   
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