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321.
Attention is drawn to a basicallyinverse correlation between some adverse weather events which occur in two adjacent zones of the Alps. Since atmospheric precipitation is known to be influenced by both air and thermal pollution which are generated by urban complexes, power plants etc., and since the occurrence and effects of some forms of precipitation in two small adjacent areas are normally reasonably concomitant, the existence of this inverse interdependence appears to be of interest. The phenomenon is discussed in terms of a simple model which fits, with excellent approximation, the data available on annual losses, due to hail of the agricultural produce in the Bolzano and Trento Provinces over the years 1970–1979 incl. This model may thus also be useful in future studies of annual precipitation changes which may locally be caused by the air polluting effects of increasing industrialization and urbanization.  相似文献   
322.
Summary After finishing a six years' program for exploring and collecting plant genetic resources in South Italy in 1986, these activities were extended to central parts of the country in September 1987 jointly by staff members of the Istituto del Germoplasma, Bari, and the Zentralinstitut für Genetik und Kulturpflanzenforschung, Gatersleben. A major part of the Abruzzi area has been covered. 165 samples, mainly of cereals, grain legumes and vegetables, could be collected. This material represents variable land-races. Two accessions ofTriticum dicoccon are especially worth mentioning.
Sammlung pflanzlicher genetischer Ressourcen in Italien 1987
Zusammenfassung Nach Beendigung eines sechsjährigen Programms zum Studium und zur Sammlung pflanzlicher genetischer Ressourcen in Süditalien im Jahre 1986, wurden diese Aktivitäten im September 1987 gemeinsam von Mitarbeitern des Istituto del Germoplasma, Bari, und des Zentralinstitus für Genetik und Kulturpflanzenforschung, Gatersleben, in mittleren Landesteilen fortgesetzt. Ein großer Teil des Abruzzi-Gebietes wurde erfaßt. 165 Proben, vor allem von Getreiden, Körnerleguminosen und Gemüsen, konnten gesammelt werden. Dieses Material setzt sich aus variablen Landsorten zusammen. Zwei Proben vonTriticum dicoccon sind besonders erwähnenswert.

1987
1986 , . . 165 , , — , . . Triticum dicoccon .
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323.
324.
Summary In continuation of collecting missions in 1980, 1981 and 1982a further mission has been carried out in South Italy jointly by staff members of the Istituto del Germoplasma, Bari, and the Zentralinstitut für Genetik und Kulturpflanzenforschung, Gatersleben, in July 1983 for studying and collecting indigenous forms of cultivated plants and their wild relatives. 277 samples, mainly of cereals, grain legumes and vegetables have been collected. The material represents highly variable old land-races; this is especially true for wheat, maize, french beans, faba beans andBrassica spp. In some fields of the Sila Mts. introgressions fromSecale montanum into cultivated rye could be observed. The results of this mission stress the necessity for continuing the exploration of plant genetic resources in South Italy.
Sammlung von Kulturpflanzen-Landsorten in Süditalien 1983
Zusammenfassung In Fortführung von Sammelreisen in den Jahren 1980, 1981 und 1982 wurde im Juli 1983 eine weitere Reise nach Süditalien gemeinsam von Mitarbeitern des Istituto del Germoplasma, Bari, und des Zentralinstituts für Genetik und Kulturpflanzenforschung, Gatersleben, unternommen, die dem Studium und der Sammlung indigener Formen von Kulturpflanzen und ihrer verwandten Wildsippen diente. 277 Proben, besonders von Getreiden, Körnerleguminosen und Gemüsen, wurden gesammelt. Das Material besteht aus hochvariablen alten Landsorten, besonders von Weizen, Mais, Gartenbohnen, Ackerbohnen undBrassica-Arten. In einigen Feldern des Sila-Gebirges konnten Introgressionen vonSecale montanum in Kulturroggen beobachtet werden. Die Ergebnisse dieser Sammelreise unterstreichen die Notwendigkeit zur Weiterführung der Exploration pflanzengenetischer Ressourcen in Süditalien.

1983
1980 . 1981 1982 . , 1983 . . 277 , , , . , , , , Brassica. Secale montanum . , .
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325.

Purpose

Microwave (MW) heating has been identified as a potential cost-effective technique to remediate hydrocarbon-polluted soils; however, the soil texture and properties could have a great impact on its full-scale treatment. In addition, very limited energy and economical data on MW treatment are available, and this lack makes its real application very limited. In this work, a first experimental phase was performed simulating a MW of several hydrocarbon-polluted soils. Obtained data were elaborated for a techno-economic analysis.

Materials and methods

Four soil textures, corresponding to medium, fine silica sand (at different soil moistures), silt as silica flour and clay as kaolin, were artificially contaminated with diesel fuel and irradiated by MWs using a bench scale apparatus. Soil samples were treated applying four specific power values at different times. At the end, soil temperature was measured, whereas residual contaminant concentrations were measured and fitted considering and exponential decay kinetic model. Temperature data, as well as kinetic parameters obtained, were used for the techno-economic analysis. The changing of the internal electric field was calculated for all the soils and operating conditions, then considering initial contamination values ranging from 750 to 5000 mg kg?1, the minimal remediation time, specific energy and costs for the remediation were assessed.

Results and discussion

At low powers, MW effectiveness is limited by low soil moistures or fine soil textures due to a limitation of the electric field penetration, whereas when high powers are used soil properties have a limited effect. Remediation time, as a function of the initial contamination level, follows a linear trend, except for dry soils, for which an exponential trend was observed. For powers higher than 30 kW Kg?1, remediation times lower than about 100 min are needed, for all the moisturized soils, in order to treat a contamination of 5000 mg kg?1. The variation of soil moisture or soil texture results in the range 20–160 € ton?1, and doubled costs are required for the treatment of clayey soils respect to sandy soils.

Conclusions

The analysis performed suggests that soil layers lower than 70 cm should be considered for ex situ remediation. MW has been shown as a quick technique also for high hydrocarbon concentrations; however, for energy saving, the application of some powers should be avoid. Unmoisturized or fine texture soil treatment results in higher costs; however, a maximum cost of 160 € ton?1 generally makes MW heating a quick and cost-effective ex situ technique.
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326.
327.
The aim of the present study was to investigate the gastroprotective activity of a sulfated-polysaccharide (PLS) fraction extracted from the marine red algae Gracilaria caudata and the mechanism underlying the gastroprotective activity. Male Swiss mice were treated with PLS (3, 10, 30 and 90 mg·kg(-1), p.o.), and after 30 min, they were administered 50% ethanol (0.5 mL/25 g(-1), p.o.). One hour later, gastric damage was measured using a planimeter. Samples of the stomach tissue were also obtained for histopathological assessment and for assays of glutathione (GSH) and malondialdehyde (MDA). Other groups were pretreated with l-NAME (10 mg·kg(-1), i.p.), dl-propargylglycine (PAG, 50 mg·kg(-1), p.o.) or glibenclamide (5 mg·kg(-1), i.p.). After 1 h, PLS (30 mg·kg(-1), p.o.) was administered. After 30 min, ethanol 50% was administered (0.5 mL/25 g(-1), p.o.), followed by sacrifice after 60 min. PLS prevented-ethanol-induced macroscopic and microscopic gastric injury in a dose-dependent manner. However, treatment with l-NAME or glibenclamide reversed this gastroprotective effect. Administration of propargylglycine did not influence the effect of PLS. Our results suggest that PLS has a protective effect against ethanol-induced gastric damage in mice via activation of the NO/K(ATP) pathway.  相似文献   
328.
Climate, soil physical–chemical characteristics, land management, and carbon (C) input from crop residues greatly affect soil organic carbon (SOC) sequestration. According to the concept of SOC saturation, the ability of SOC to increase with C input decreases as SOC increases and approaches a SOC saturation level. In a 12‐year experiment, six semi‐arid cropping systems characterized by different rates of C input to soil were compared for ability to sequester SOC, SOC saturation level, and the time necessary to reach the SOC saturation level. SOC stocks, soil aggregate sizes, and C inputs were measured in durum wheat monocropping with (Ws) and without (W) return of aboveground residue to the soil and in the following cropping systems without return of aboveground residue to soil: durum wheat/fallow (Wfall), durum wheat/berseem clover, durum wheat/barley/faba bean, and durum wheat/Hedysarum coronarium. The C sequestration rate and SOC content were lowest in Wfall plots but did not differ among the other cropping systems. The C sequestration rate ranged from 0.47 Mg C ha−1 y−1 in Ws plots to 0.66 Mg C ha−1 y−1 in W plots but was negative (−0.06 Mg C ha−1 y−1) in Wfall plots. Increases in SOC were related to C input up to a SOC saturation value; over this value, further C inputs did not lead to SOC increase. Across all cropping systems, the C saturation value for the experimental soil was 57.7 Mg ha−1, which was reached with a cumulative C input of 15 Mg ha−1. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
329.
Elaeis oleifera or ‘caiaué’, a close relative of oil palm (E. guineensis), has some agronomic traits of great interest for the oil palm genetic breeding such as slow growth, oil quality (mostly unsaturated) and disease resistance. An analysis of a Brazilian oil palm germplasm collection was carried out using RAPD (Random Amplified Polymorphic DNA) markers with the objective of understanding the genetic variation of ‘caiaué’ accessions collected in the Amazon Forest in the last two decades. A sample of 175 accessions obtained along the Amazon River Basin was analyzed and compared to 17 accessions of oil palm from Africa. Ninety-six RAPD markers were used in the analysis, of which fourteen were shown to be specific to oil palm, while twelve were specific to ‘caiaué’. Results showed that the Brazilian ‘caiaué’ accessions studied have moderate levels of genetic diversity as compared to oil palm accessions. The data allowed the establishment of similarity groups for ‘caiaué’ accessions, which is useful for selecting parental plants for population breeding. Cluster analysis showed that, in general, genetic similarities are not correlated to geographical distances, but consistent with geographical dispersal along the Amazon River network. AMOVA showed that most of the genetic variation is found within populations, as expected for anallogamous and long-lived perennial species. The study provides important information to define strategies for future collection expeditions, for germplasm conservation and for the use of E. oleifera in breeding programs. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
330.
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