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331.
The fauna of Zygentoma from Italy is reviewed and extended by new data. Ctenolepisma guadianica and Allacrotelsa kraepelini are new to Italy (the second one is also a new genus for this country). Neoasterolepisma crassipes is new to continental Italy and Atelura formicaria is new to Sicily. Neoasterolepisma angustothoracica (Grassi & Rovelli, 1890) n. comb., is redescribed.The Zygentoma fauna of Italy is composed of 24 species, 2 of Ateluridae (Atelura formicaria and Proatelurina pseudolepisma), 16 of Lepismatidae (Allacrotelsa kraepelini, Ctenolepisma algharbica, C. ciliata, C. guadianica, C. lineata, C. longicaudata, C. targionii, Lepisma chlorosoma, L. saccharina, Neoasterolepisma angustothoracica, N. balcanica, N. crassipes, N. wasmanni, Thermobia domestica, Tricholepisma aurea and T. gyriniformis) and 6 of Nicoletiidae (Coletinia maggi, C. setosula, C. subterranea, Coletinia sp. III, Lepidospora sp. and Nicoletia phytophila). A key to the identification of all these species is given.  相似文献   
332.
333.
The sensorial representativeness of the headspace solid-phase microextraction (HS-SPME) aroma extract from commercial Sherry vinegars has been determined by direct gas chromatography-olfactometry (D-GCO). Extracts obtained under optimal conditions were used to characterize the aroma of these vinegars by means of GCO and aroma extract dilution analysis (AEDA). Among the 37 different odorants determined, 13 of them were identified for the first time in Sherry vinegars: 2 pyrazines (3-isopropyl-2-methoxypyrazine, 3-isobutyl-2-methoxypyrazine), 2 sulfur compounds (methanethiol, dimethyl trisulfide), 1 unsaturated ketone (1-octen-3-one), 1 norisoprenoid (β-damascenone), 1 ester (ethyl trans-cinnamate) and 6 aldehydes (2- and 3-methylbutanal, octanal, nonanal, (E)-2-nonenal and (E,E)-2,4-decadienal). The determination of the odor thresholds in a hydroacetic solution together with the quantitative analysis-which was also performed using the simple and fast SPME technique-allowed obtaining the odor activity values (OAV) of the aromatic compounds found. Thus, a first pattern of their sensory importance on commercial Sherry vinegar aroma was provided.  相似文献   
334.
The behavior in the field and the transfer from olives to olive oil during the technological process of imidacloprid, thiacloprid, and spinosad were studied. The extraction method used was effective in extracting the analytes of interest, and no interfering peaks were detected in the chromatogram. The residue levels found in olives after treatment were 0.14, 0.04, and 0.30 mg/kg for imidacloprid, thiacloprid, and spinosad, respectively, far below the maximum residue levels (MRLs) set for these insecticides in EU. At the preharvest interval (PHI), no residue was detected for imidacloprid and thiacloprid, while spinosad showed a residue level of 0.04 mg/kg. The study of the effect of the technological process on pesticide transfer in olive oil showed that these insecticides tend to remain in the olive cake. The LC/DAD/ESI/MS method showed good performance with adequate recoveries ranging from 80 to 119% and good method limits of quantitation (LOQs) and of determination (LODs). No matrix effect was detected.  相似文献   
335.
The saponin composition of leaves from the Medicago polymorpha cultivars 'Santiago' and 'Anglona' belonging to the botanical varieties brevispina and vulgaris, respectively, was investigated by a combination of chromatographic, spectroscopic, and spectrometric techniques. Several compounds were detected and quantitated by HPLC analysis using the external standard method. Twelve triterpene saponins (1-12) were purified by reverse-phase chromatography and their structures elucidated by spectroscopic (1D and 2D NMR, ESI-MS/MS) and chemical methods. They were identified as glycosides of echinocystic acid, hederagenin, caulophyllogenin, bayogenin, and soyasapogenol B. Two of them (2, 10) were previously reported in M. polymorpha; five of them (4, 6, 7, 9, 12) were already identified in other Medicago species; and three of them (1, 8, 11) were found in other plant genera. The two saponins identified as 3-O-α-L-arabinopyranosyl-28-O-[β-D-glucopyranosyl(1→6)β-D-glucopyranoside] echinocystic acid (3) and 3-O-α-L-arabinopyranosyl-28-O-β-D-glucopyranoside echinocystic acid (5) are newly identified natural compounds. The presence of echinocystic acid is reported here for the first time in the genus Medicago. Saponins from the cultivar 'Anglona' were characterized by a higher amount of echinocystic acid glycosydes, whereas saponins from the cultivar 'Santiago' were characterized by a higher amount of hederagenin glycosydes.  相似文献   
336.
337.
The main objectives were to study the effect of gap size and canopy openness on the natural regeneration dynamics considering the parameters of sapling growth, recruitment, mortality, density, species composition and above-ground biomass accumulation. The study was carried out in 32 artificial gaps with sizes varying from 100 to 1200 m2 and canopy openness from 10 to 45%, from the second to the twelfth year after gap creation. The gap size was measured using the vertical projection of the tree crowns on the ground (Brokaw's definition), and the canopy openness measurement by hemispherical photography. In the first five years, mean sapling growth (0.54 cm year−1), mortality (3.9% year−1) and AGB (26.2 Mg ha−1 or 8.7 Mg ha−1 year−1) were significantly higher in the gaps than in the forest understorey (0.17 cm year−1, 1.5% year−1 and −0.59 Mg ha−1 year−1 respectively) and positively correlated with gap size and canopy openness. In the same period, recruitment was also significantly higher in the gaps (5.8% year−1) than in the forest understorey (0.4% year−1) but decreased with gap size and negatively correlated with canopy openness. In the first five years, the relative density of pioneer species was higher in the gaps but not significantly correlated with gap size or canopy openness. AGB increased linearly since canopy opening, and twelve years after gap creation it was still higher in larger (121.2 Mg ha−1 or 10.1 Mg ha−1 year−1) rather than smaller (62.5 ha−1 or 5.2 ha−1 year−1) gaps. Twelve years after gap creation there were no significant differences in the parameters of sapling growth, recruitment, and mortality which could be attributed to the original gap size and canopy openness.  相似文献   
338.
Variation and geographic distribution of stem solidness and environmental stress tolerance were assessed under dryland conditions in a collection of 2420 durum wheat landrace morphotypes collected in 28 administrative provinces of Turkey. The former trait is known to confer resistance to wheat stem sawfly – a serious pest insect in West Asia and North Africa. Both characters were scored on a visual five-level scale. Score mean values and frequency distributions in the different provinces were significantly different for both traits according to analysis of variance and chi-square test, respectively. Two groups of provinces emerged with high frequency of solid-stemmed, and hollow-stemmed accessions, respectively. The former could be of interest in durum wheat breeding against the sawfly. The group of solid-stemmed province germplasms was collected at lower altitude than the other, being also different on average for higher temperatures and evapotranspiration, and shorter growing season at sites of origin. Overall frequency of morphotypes tolerant to stress conditions prevailing in the evaluation site was rather low (10%). This low frequency may be due to low adaptation of materials in this harsher environment than those of origin where rainfall is usually higher and temperatures markedly lower. Nonetheless, differences among provinces in frequency distribution of stress tolerant morphotypes were evidenced. The relatively more tolerant gene pools originated either along the western coast or in the southern part of the country, along the Fertile Crescent. The least tolerant province germplasms originated either in the North along the Black Sea or in the highlands of the eastern Anatolian Plateau. Germplasm from provinces Malatya and Izmir combined good levels of both stem solidness and stress tolerance.  相似文献   
339.
Summary Paper chromatography was applied to investigate the distribution of flavonoids plus other not identified phenols in ten species ofVicia.Considerable biochemical differences were found between as well as within species. The extract ofV. cordata produced a chromatogram substantially different from other taxa of theV. sativa aggregate which confirms its separation as species. The similarity in flavonoids betweenV. villosa andV. dasycarpa supports the view of considering the latter as a subspecies of the former. Similar comments are made on the other species investigated.Cluster analysis may be useful for studying species relationships. It suggests the existence of a parallel between evolutionary advancement and degree of diversification. The results of this small survey would encourage the use of flavonoids and other secondary products for improving the existing classification of the genus.
Ein chromatographischer Beitrag zur Taxonomie vonVicia L.
Zusammenfassung Papierchromatographie wurde zur Analyse des Vorkommens von Flavonoiden und weiteren nicht identifizierten phenolischen Verbindungen in 10Vicia-Arten genutzt.Betiächtliche biochemische Unterschiede wurden sowohl zwischen als auch innerhalb von Arten ermittelt. Der Extrakt vonV. cordata ergab ein wesentlich von anderen Taxa desV. sativa-Aggregats abweichendes Chromatogramm, das die Abgliederung dieser Sippe als eigene Art bestätigte. Andererseits stützt die Ähnlichkeit der Flavonoide vonV. villosa andV. dasycarpa deren Zusammenfassung als 2 Unterarten einer Art. Ähnliche Kommentare waren bei anderen untersuchten Arten möglich.Die Cluster-Analyse konnte erfolgreich zur Einschätzung der Verwandtschaft zwischen den Arten herangezogen werden. Mit ihrer Hilfe ergab sich eine Parallele zwischen dem Grad abstammungsgeschichtlicher Ableitung und dem Ausmaß der Differenzierung.Die Ergebnisse dieser ersten Übersicht ermutigen zur weiteren Verwendung von Flavonoiden und anderen sekundären Pflanzenstoffen bei der Optimierung der Klassifikation der Gattung.

Vicia L.
10 Vicia. , . V. cordata , V. sativa, ¶rt; . , V. villosa V. dasycarpa . . . . .
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340.
Summary Exploration and collection of plant genetic resources were continued in South Italy in 1988. Parts of the regions Campania, Basilicata and Apulia were covered in September jointly by staff members of the Istituto del Germoplasma, Bari, and the Zentralinstitut für Genetik und Kulturpflanzenforschung, Gatersleben. 164 samples, mainly of vegetables and grain legumes, have been collected. Worth mentioning are land-races of tomatoes,Brassica spp. andVigna unguiculata. As a part of the collecting area has been explored for the second time after eight years, the effects of genetic erosion could be observed. A map summarizes the itineraries of the ten joint collecting missions in South Italy.
Sammlung pflanzlicher genetischer Ressourcen in Süditalien 1988
Zusammenfassung Die Exploration und Sammlung pflanzlicher genetischer Ressourcen wurden 1988 in Süditalien fortgesetzt. Im September wurden Teile der Regionen Campania, Basilicata und Apulia gemeinsam von Mitarbeitern des Istituto del Germoplasma, Bari, und des Zentralinstituts für Genetik und Kulturpflanzenforschung, Gatersleben, erfaßt. 164 Proben, besonders von Gemüsen und Körnerleguminosen, wurden gesammelt. Erwähnenswert sind Landsorten von Tomaten, Kohlarten undVigna unguiculata. Da ein Teil des Sammelgebietes im Abstand von acht Jahren ein zweites Mal in die Exploration einbezogen wurde, konnte das Wirken der Generosion verfolgt werden.Die Reiserouten der zehn gemeinsamen Sammelreisen in Süditalien werden zusammenfassend in einer Karte dargestellt.

1988
1988. . . () (). 164 . . , Vigna unguiculata. 8 . .
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