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331.
PM10 particles were collected over three sites in France. The first one, Montagney was a rural site that was considered as a reference site. The second site Saclay, close to a highway, was used to study the influence of the traffic. The third site was Dunkerque, one of the most industrial areas in France for the production of steel, aluminium and petroleum refinement. More than 50 element concentrations were determined by instrumental neutron activation analysis and inductively coupled plasma–mass spectrometry. Comparisons between Saclay and Montagney shown that some elements, considered as crustal elements had similar concentration variations and weak (close to 1) enrichment factors. Elements with enrichment factors higher than 10 shown in Montagney correlated variations, with a Winter maximum, that should be due to Winter heating sources. Over Saclay, most of elements with high enrichment factors were attributed to the dense traffic of the highway. This is particularly true for Mn, Fe, Zn, Ba, Sb, Cu. Some additional elements correlated also, without a particular origin that can be ascertained. In Dunkerque, the most important industry is steel production. Correlation studies shown that Tl, Cs, Ba, Ag, Cu, Rb, Se, Mn, Pb concentration variations were closely associated to the Fe concentration variations. The second polluting industry is aluminium production. Correlation studies allowed to associate Ni, Y, Co, V, rare earth elements, Ti, Sr, Th, U, Ca, Sc, concentration variations to the aluminium concentration variations. A third important industry is petroleum refinement. The only element observed here and that is suspected to be emitted more specifically is La, used in cracking processes. An important enrichment of La with respect to Ce is observed. A strong decrease of the ratio Cl/Na was observed over the three sites, between the beginning of the experiment in Autumn 2005, and its end in Spring 2006. This was attributed to a release of gaseous HCl, produced by acidification of aerosols by other pollutants like NO x and SO x , that should have been oxidized to NO2 and SO3, then dissolved in the aerosols. The effects responsible for the loss of Cl, represents a large surface and long-term pollution event over the North of France. This work allowed a characterization of the heavy metal concentrations of the aerosol that will sustain results published in a companion paper, and that concerned the bio-accumulation of metals by Scleropodium purum, simultaneously exposed in the same sites.  相似文献   
332.
BACKGROUND: Herbicides that affect lipid metabolism have been used commercially for many years. Here, napropamide, diphenamid, dimethachlor and cafenstrole are compared; these have all been classified by the Herbicide Resistance Action Committee (HRAC) as K3 herbicides and inhibitors of cell division and/or synthesis of very‐long‐chain fatty acids (VLCFAs). In addition, spiro‐decanedione A and pinoxaden dione are compared as inhibitors of lipid synthesis through inhibition of acetyl‐CoA carboxylase (ACCase). RESULTS: Whereas the chloracetamide dimethachlor and the carboxyamide cafenstrole potently inhibited VLCFA synthesis in both barley and cucumber, the acetamides napropamide and diphenamid which are also classified as K3 herbicides and likewise the unclassified herbicide cinmethylin did not. The graminicide pinoxaden dione inhibited de novo fatty acid synthesis in barley, but not in cucumber, and correspondingly inhibited the plastid form of maize ACCase much more than the cytosolic form (IC50 values of 0.1 and 17 µM ). By contrast, spiro‐decanedione A exhibited herbicidal effects not only on grasses but also on broad leaves, strongly inhibited maize cytosolic ACCase and inhibited synthesis of VLCFAs in cucumber. CONCLUSIONS: The acetamides napropamide and diphenamid, which do not inhibit VLCFA synthesis, should be classified separately from K3 herbicides that do. Pinoxaden dione and spiro‐decanedione A represent new classes of chemicals acting on plant lipid synthesis. Copyright © 2010 Society of Chemical Industry  相似文献   
333.
For the last 10 years, the European and Mediterranean Plant Protection Organization (EPPO) has run a European Panel on diagnostics, which has developed regional standards on diagnostic protocols. Nearly 80 such standards have now been approved, and are in active use in EPPO countries. In 2003, the Commission for Phytosanitary Measures (CPM) of FAO, in reviewing global needs for International Standards for Phytosanitary Measures (ISPMs), recognized that there is a strong interest in developing diagnostic protocols for all contracting parties to the International Plant Protection Convention (IPPC). Such protocols would support the harmonization of detection and identification procedures worldwide, contribute to greater transparency and comparability in the diagnostics for regulated pests, and assist in the resolution of disputes between trading partners. In addition, such protocols would be very useful in technical assistance programmes. In 2004, the CPM adopted a mechanism for rapid development of ISPMs in specific areas, particularly suitable for diagnostic protocols. A Technical Panel was accordingly established to develop protocols for specific pests and meets on an annual basis. A format for international diagnostic protocols was adopted in 2006 and a list of priority pests was established. In 2003, EPPO initiated a new programme on quality management and accreditation for plant pest laboratories and Standards are now also being developed in this area. In 2006, a survey of existing diagnostic capacities in EPPO member countries was undertaken and a database on diagnostic expertise was created.  相似文献   
334.
In forests worldwide, ~10?40% of bird and mammal species require cavities for nesting or roosting. Although knowledge of tree cavity availability and dynamics has increased during past decades, there is a striking lack of studies from boreal Europe. We studied the density and characteristics of cavities and cavity-bearing trees in three categories of forest in a north-Swedish landscape: clearcuts with tree retention, managed old (>100 years) forest, and unmanaged old forest. Unmanaged old forests had significantly higher mean density of cavities (2.4?±?2.2(SD)?ha?1) than managed old forest (1.1?±?2.1?ha?1). On clearcuts the mean cavity density was 0.4?±?2.3?ha?1. Eurasian aspen (Populus tremula) had a higher probability of containing excavated cavities than other tree species. There was a greater variety of entrance hole shapes and a higher proportion of cavities with larger entrances in old forest than on clearcuts. Although studies of breeding success will be necessary to more accurately assess the impact of forest management on cavity-nesting birds, our results show reduced cavity densities in managed forest. To ensure future provision of cavities, managers should retain existing cavity-bearing trees as well as trees suitable for cavity formation, particularly aspen and dead trees.  相似文献   
335.
Deserts exhibit extreme climatic conditions. Small desert‐dwelling vertebrates have physiological and behavioral adaptations to cope with these conditions, including the ability to seek shelter. We investigated the temperature (T) and relative humidity (RH) regulating properties of the soil cracks that characterize the extensive cracking‐clay landscapes of arid Australia, and the extent of their use by 2 small marsupial species: fat‐tailed and stripe‐faced dunnarts (Sminthopsis crassicaudata and Sminthopsis macroura). We measured hourly (over 24‐h periods) the T and RH of randomly‐selected soil cracks compared to outside conditions, during 2 summers and 2 winters. We tracked 17 dunnarts (8 Sminthopsis crassicaudata and 9 Sminthopsis macroura) to quantify their use of cracks. Cracks consistently moderated microclimate, providing more stable conditions than available from non‐crack points, which often displayed comparatively dramatic fluctuations in T and RH. Both dunnart species used crack shelters extensively. Cracks constitute important shelter for small animals during extreme conditions by providing a stable microclimate, which is typically cooler than outside conditions in summer and warmer in winter. Cracks likely play a fundamental sheltering role by sustaining the physiological needs of small mammal populations. Globally, cracking‐clay areas are dominated by agricultural land uses, including livestock grazing. Management of these systems should focus not only on vegetation condition, but also on soil integrity, to maintain shelter resources for ground‐dwelling fauna.  相似文献   
336.
337.
The present study was conducted to determine the prevalence and incidence of trypanosomosis and to investigate some factors influencing them in an agro-pastoral area of southwestern Burkina Faso. A total of 363 crossbred cattle (Baoule-zebu peul), which were bred under natural trypanosomosis challenge, were monitored monthly for parasitaemia, packed cell volume (PCV) and serological analyses over 2 years. The parasitological prevalence estimated at the beginning of the survey using the buffy coat technique (BCT) was 7.54%. As much as 66.7% of all trypanosome infections were due to Trypanosoma vivax, 23.8% due to Trypanosoma congolense and 9.5% due to T. vivax/T. congolense mixed infections. The monthly serological incidence varied from 0.29% to 19.29%.The season was the most important factor influencing the serological prevalence and incidence and the animal PCV. The dry hot season is associated with increasing seroprevalences and incidences and consequently a decreasing average of PCV. In addition, an important spatial heterogeneity was observed.  相似文献   
338.
Six commercially grown samples of hard spring wheat were milled using a tandem Buhler laboratory mill. Individual flour streams and branny by‐products, as well as whole‐grain wheat and straight‐grade flour, were characterized in terms of total (TP), water‐extractable (WEP), and water‐unextractable (WUP) pentosans. One representative cultivar sample was analyzed for its ratio of arabinose to xylose (A/X). TP and WEP of whole grain wheat of the six samples had ranges of 5.45–7.32% and 0.62–0.90% (dm), respectively. Neither TP nor WEP of whole grain was related to ash content variation. There was significant variation in the distribution and composition of pentosans in 16 millstreams of all the wheat samples, including bran and shorts fractions; TP and WEP contents had ranges of 1.69–32.4% and 0.42–1.76% (dm), respectively. When ash contents exceeded ≈0.6% (dm), strong positive correlations were obtained between ash and TP contents, and between ash and WUP contents for all the millstreams. Among bran and shorts fractions, TP and WUP content increased in the order of coarse bran > fine bran > shorts; while WEP, WEP/WUP and A/X showed the opposite pattern of variation of shorts > fine bran > coarse bran. Bran and shorts fractions had pentosan contents several times higher than would be predicted from the relationship between pentosan and ash contents of the flour streams. Pentosans therefore represented a much more sensitive marker of flour refinement compared with ash content. Pentosans of endosperm were substantially different in their extractability and composition from those of bran. On this basis, different functionalities of pentosans of bran and endosperm would be expected. Results demonstrated the importance of milling extraction and millstream blending in the functionality and quality of wheat flour for breadmaking.  相似文献   
339.
A saline extract of boiled-formalinized whole cells from a local strain (81–750; Quebec, Canada) of Actinobacillus pleuropneumoniae, serotype 5b was used as an antigen in an enzyme-linked immunosorbent assay (ELISA) for serodiagnosis of swine pleuropneumonia. Characterization of this crude extract was done and proteins, neutral sugars, hexosamines, and 2-keto-3-deoxyoctonate (KDO) were evaluated. On phenol extraction of the crude extract a serotype-specific antigen of polysaccharidic nature was recovered from the aqueous phase. This antigen was characterized using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) with Coomassie blue, silver and Schiff stainings. Immunoblots were done using sera of experimentally infected pigs that showed serotype specificity and cross-reactivity. Overall, the results indicate that the O-chain of lipopolysaccharides is a specific antigen that could be used in ELISA for the serodiagnosis of serotype 5 of A. pleuropneumoniae.  相似文献   
340.
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