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81.
Bergamot (Citrus bergamia, Risso) is a fruit most knowledgeable for its essential oil (BEO) used in aromatherapy to minimize symptoms of stress-induced anxiety and mild mood disorders and cancer pain though the rational basis for such applications awaits to be discovered. The behavioural and EEG spectrum power effects of BEO correlate well with its exocytotic and carrier-mediated release of discrete amino acids endowed with neurotransmitter function in the mammalian hippocampus supporting the deduction that BEO is able to interfere with normal and pathological synaptic plasticity. The observed neuroprotection in the course of experimental brain ischemia and pain does support this view. In conclusion, the data yielded so far contribute to our understanding of the mode of action of this phytocomplex on nerve tissue under normal and pathological experimental conditions and provide a rational basis for the practical use of BEO in complementary medicine. The opening of a wide venue for future research and translation into clinical settings is also envisaged.  相似文献   
82.
This study aims to investigate wood density at different levels of moisture, basic density and shrinkage of timber from Turkey oak (Quercus cerris L.) coppice forests growing in Central Italy. We also studied the variability in density in the trees within and among sites. Density shows no significant statistical differences in the tested population. A higher variability in the shrinkage than in the density was found. Wood moisture is referred to as dry mass and fresh mass, which is related to many performance characteristics of wood, i.e., energy production. Trends in moisture and water content were studied because these physical parameters play an important role in the specific area of firewood which requires an accurate estimation of mass, volume and energy content. This work is a contribution to improve xylo-energy estimates of small and medium forestry issues.  相似文献   
83.
A combined effect of steaming and heat treatment was imposed on green Turkey oak wood, both for sapwood and heartwood. Steaming was carried out in an autoclave at 100–120–130°C whereas heating was carried out in an oven for 2?h at 120–180°C. Equilibrium moisture content at dry, intermediate and moist state both in desorption and adsorption, swelling, cup, twist, color change, and spectral reflectance measures were registered. Swelling and water absorption decreased due to the hydro-thermal treatment. During adsorption, heartwood showed a higher hygroscopic inertia compared to sapwood and this difference increased with temperature. Cup increased with temperature in the steaming process. Twist seemed to be affected more by quality of original trunks than treatments. The wood color was more sensitive at a steaming temperature of 130°C combined with heat treatment at 180°C. Transitional treatments assured more reliable results on homogenization of hue between sapwood and heartwood.  相似文献   
84.
High tolerance of European plum varieties to plum leptonecrosis   总被引:1,自引:0,他引:1  
A 13 year comparative study was carried out on the behaviour of four European and two Japanese plum varieties grown in adjacent rows in an area of northern Italy where plum leptonecrosis is epidemic. Within seven years, 100% of the Japanese plum trees became symptomatically infected. Nine years after planting, five trees of each of the European cvs, which were asymptomatic, were top-grafted with healthy buds of the cv Ozark Premier, which is an indicator for plum leptonecrosis. Based on the results of PCR analysis, DAPI staining and on the reaction of the top-grafted Ozark Premier indicators, 50% of the European plum trees, despite their healthy appearance, were shown to be infected with plum leptonecrosis. The detectable presence and graft transmissibility of the plum leptonecrosis phytoplasma in the asymptomatic European plum trees means that the European plum trees are not resistant to the infection but that they are tolerant. The active presence of a still unknown vector/s in the investigated area is stressed as well as the important role of Prunus domestica L. played in the conservation and spread of plum leptonecrosis.  相似文献   
85.
Powdery mildews (PMs) cause disease in a wide range of plant species including important crops. Taking tomato as an example, here we review findings on the genetic basis and mechanisms of plant resistance to PMs. First, we present a summary of our research on tomato resistance to two PM species, with the focus on Oidium neolycopersici. We discuss the genetics of resistance to this pathogen in tomato. Then, we compare different forms of resistance mediated by different resistance genes based on molecular and cytological data. Also, we provide a comparison between these resistance genes in tomato with those in barley, Arabidopsis and wheat, in order to present a model for the genetic basis of resistance to PMs in plants. We try to accommodate these resistance mechanisms in the current model of plant innate immunity. At the end we discuss possibilities to translate these findings to practical approaches in breeding for resistance to PMs in crops.  相似文献   
86.
87.
Normative regulations on benzene in fuels and urban management strategies are expected to improve air quality. The present study deals with the application of self-organizing maps (SOMs) in order to explore the spatiotemporal variations of benzene, toluene, ethylbenzene, and xylene levels in an urban atmosphere. Temperature, wind speed, and concentration values of these four volatile organic compounds were measured after passive sampling at 21 different sampling sites located in the city of Trieste (Italy) in the framework of a multi-year long-term monitoring program. SOM helps in defining pollution patterns and changes in the urban context, showing clear improvements for what concerns benzene, toluene, ethylbenzene, and xylene concentrations in air for the 2001–2008 timeframe.  相似文献   
88.
Worldwide, a variety of pathogens negatively affect potato production, resulting in an estimated 22% annual yield reduction. Wild Solanum species represent a unique gene pool where all the traits necessary to improve the cultivated potato can be found. Therefore, breeding efforts for improved disease resistance and research aimed at characterizing wild germplasm have been extensively made. In this paper, sources of resistance to Phytophthora infestans, Erwinia carotovora subsp. carotovora, Fusarium solani and Globodera spp. have been investigated in several clones of two Solanum species originating from Central Mexico (S. bulbocastanum and S. cardiophyllum). Interestingly, we found sources of combined resistance to late blight and bacterial soft rot. This is an important finding considering that the development of resistant potato varieties has been hindered by the scarcity of resistant germplasm. In addition, we explored molecular differences within and between the two species generating AFLP fingerprints. By means of six primer pair combinations, we found 13 and 16 putative species-specific AFLP markers for S. bulbocastanum and S. cardiophyllum, respectively, and a bounty of markers useful for mapping, MAS, and cloning purposes. The phenotypic and molecular information associated to S. bulbocastanum and S. cardiophyllum for designing strategies of assisted selection are discussed.  相似文献   
89.
The chemical composition of 30 samples of juices obtained from bergamot (Citrus bergamia Risso and Poit.) fruits is reported and compared to the genuineness parameters adopted by Association of the Industry of Juice and Nectars (AIJN) for lemon juice. It was found that the compositional differences between the two juices are distinguishable, although with difficulty. However, these differences are not strong enough to detect the fraudulent addition of bergamot juice to lemon juice. Instead, we found the high-performance liquid chromatography (HPLC) analysis of the flavanones naringin, neohesperidin, and neoeriocitrin, which are present in bergamot juice and practically absent in the lemon juice, is a convenient way to detect and quantify the fraudulent addition of bergamot juice. The method has been validated by calculating the detection and quantification limits according to Eurachem procedures. Employing neoeriocitrin (detection limit = 0.7 mg/L) and naringin (detection limit = 1 mg/L) as markers, it is possible to detect the addition of bergamot juice to lemon juice at the 1% level. When using neohesperidin as a marker (detection limit = 1 mg/L), the minimal percentage of detectable addition of bergamot juice was about 2%. Finally, it is reported that the pattern of flavonoid content of the bergamot juice is similar to those of chinotto (Citrus myrtifolia Raf) and bitter orange (Citrus aurantium L.) juices and that it is possible to distinguish the three kinds of juices by HPLC analysis.  相似文献   
90.
The chemical composition of the volatile fractions from leaves of three Olea europaea L. cultivars (Leccino, Frantoio, and Cipressino) harvested at two different times of the year were examined by GC and GC-MS. The results showed a high content of aliphatic aldehydes in the three cultivars during both harvesting periods and an increase of (E)-2-hexenal (an aldehyde with high antimicrobial properties) percentage from July to November.  相似文献   
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