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131.
A juvenile nephropathy in a 4-year-old male Boxer dog, closely resembling the Nephronophthisis (NPHP)-Medullary Cystic Kidney Disease Complex (MCKD) in humans is described. Gross examination of the kidneys revealed several multiple cysts at the corticomedullary junction and in the medulla. Histological examination was characterized by a widespread tubular atrophy and dilatation, with a marked thickening of the tubular basement membrane, interstitial lymphocytic infiltration and fibrosis. Ultrastructural studies revealed dilated tubules with irregular basement membrane thickening and splitting. Lectin histochemistry investigation revealed that the cysts originated in the distal convoluted tubule and collecting duct. Having excluded all other known cystic diseases of the kidney, and based on the lectin histochemistry results, the macroscopic and histological findings of our case are highly compatible with a diagnosis of the NPHP-MCKD complex. To our knowledge, this is the first report describing this particular lesion.  相似文献   
132.
Three olive cultivars (Oliva Nera di Colletorto, Noccioluta, and a probably a new local genotype) from two strictly related areas of Molise region (south-centre of Italy) were characterized by combining molecular data (eight SSRs analyzed on leaves) and morphological features (thirty-one parameters from leaves, drupes and pits). Both molecular and morphological analyses have shown a very good separation of the three endemic cultivars. A high correlation between morphological and molecular data was found using Mantel's test. The morphological traits of pits were less influenced by environmental pressure than the leaves and drupes; therefore, the pits are more affected by genetic control and might be considered a helpful tool for cultivar characterization and identification. Potential and limitations of three statistical models computed to perform cultivar identification by morphological measures is also discussed. We demonstrated that molecular and morphological analyses are useful for distinguishing new accessions and studying local varieties to preserve genetic diversity, even at small geographical scale in such an unequivocal way; hence the methodology could be proposed as a tool to discriminate widespread cultivars, with long genetic distances.  相似文献   
133.
In addition to its search for extrasolar planets, the NASA Kepler mission provides exquisite data on stellar oscillations. We report the detections of oscillations in 500 solar-type stars in the Kepler field of view, an ensemble that is large enough to allow statistical studies of intrinsic stellar properties (such as mass, radius, and age) and to test theories of stellar evolution. We find that the distribution of observed masses of these stars shows intriguing differences to predictions from models of synthetic stellar populations in the Galaxy.  相似文献   
134.
A strategy is presented for determining sublattice polarity at defects in compound semiconductors. Core structures of 60-degree and Lomer dislocations in the CdTe/GaAs(001) system have been obtained by the application of maximum-entropy analysis to Z-contrast images (Z is atomic number) obtained in a 300-kilovolt scanning transmission electron microscope. Sixty-degree dislocations were observed to be of the glide type, whereas in the case of Lomer dislocations, both a symmetric (Hornstra-like) core and an unexpected asymmetric structure made up of a fourfold ring were seen.  相似文献   
135.
Nuclear export of microRNA precursors   总被引:2,自引:0,他引:2  
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136.
Marine sponges commonly host a repertoire of bacterial-associated organisms, which significantly contribute to their health and survival by producing several anti-predatory molecules. Many of these compounds are produced by sponge-associated bacteria and represent an incredible source of novel bioactive metabolites with biotechnological relevance. Although most investigations are focused on tropical and temperate species, to date, few studies have described the composition of microbiota hosted by Antarctic sponges and the secondary metabolites that they produce. The investigation was conducted on four sponges collected from two different sites in the framework of the XXXIV Italian National Antarctic Research Program (PNRA) in November–December 2018. Collected species were characterized as Mycale (Oxymycale) acerata, Haliclona (Rhizoniera) dancoi, Hemigellius pilosus and Microxina sarai by morphological analysis of spicules and amplification of four molecular markers. Metataxonomic analysis of these four Antarctic sponges revealed a considerable abundance of Amplicon Sequence Variants (ASVs) belonging to the phyla Proteobacteria, Bacteroidetes, Actinobacteria and Verrucomicrobia. In particular, M. (Oxymycale) acerata, displayed several genera of great interest, such as Endozoicomonas, Rubritalea, Ulvibacter, Fulvivirga and Colwellia. On the other hand, the sponges H. pilosus and H. (Rhizoniera) dancoi hosted bacteria belonging to the genera Pseudhongella, Roseobacter and Bdellovibrio, whereas M. sarai was the sole species showing some strains affiliated to the genus Polaribacter. Considering that most of the bacteria identified in the present study are known to produce valuable secondary metabolites, the four Antarctic sponges could be proposed as potential tools for the discovery of novel pharmacologically active compounds.  相似文献   
137.
A three-year field experiment (2006–2008) was carried out in Mediterranean conditions to study the effects of organic fertilizers application on yield performance and plant nitrogen (N) status of melon crops. Soil properties at the end of experiment were further investigated. In a strip-plot experimental design, two irrigations and the following four fertilizer treatments were compared: mineral fertilizer (Min); commercial stable manure (Org); anaerobic digestate (WDD); composted municipal solid organic wastes (SUW). The results showed no statistical differences among the four different treatments on melon yields. Conversely, the highest irrigation treatment showed a significantly higher total yield (34%) and fruits number (26%). During cropping cycles, the Min treatment reached the highest mean nitrate content with an increase of about 59% and 154% respectively compared with Org and mean of WDD and SUW. The WDD and SUW significantly increased soil total, extracted and humified organic carbon of the 14, 22 and 12% compared with Min. Among treatments, no significant difference was found for heavy metals excepted for Cu, which reached the highest level in WDD treatment.  相似文献   
138.
Abstract

The aim of this study was to evaluate the effect of forms of application and application rates of phosphate fertilizer on the agronomic characteristics of carrot. A field experiment was carried out in a 2?×?7 factorial arrangement, consisting of two forms of application of the P source (over the whole area or specifically in the strip of the double row), and seven application rates of P2O5 in randomized blocks, with four replicates. Shoot dry matter yield increased linearly, and root dry matter yield increased exponentially with an increase in P rate. Total and commercial yields increased exponentially, with higher yield for P application over the whole area. However, the agronomic efficiency for site-specific application was higher. Higher rates of P application caused increases in the soil attributes and technical traits of carrot, and the application of phosphorus fertilizer is more efficient when performed in a site-specific manner.  相似文献   
139.
  1. This study presents data on a local population of short-beaked common dolphin monitored in the waters off Ischia Island (Gulf of Naples, Italy) over a 16-year period (2000-2015). We examine dolphin occurrence and distribution and perform photoidentification analysis.
  2. The data presented support the hypothesis that the waters around Ischia Island represent a feeding area, as well as a calving and an important nursery area for this local population, providing favourable conditions in which to give birth and raise calves.
  3. The levelling-off of the photoidentification curves together with the continuous decline of the encounter rate lead us to believe that the area has been a hotspot for a local population (mainly resident) for years and that now this population is dying (has died) or is moving (has moved) to other locations.
  4. Several expanding human activities at sea have the potential to impact on the common dolphin in the study area, the most significant possibly being habitat disturbance and degradation (including traffic and noise pollution) and overexploitation of food resources by the fishery.
  5. The data presented in this study offer a strong argument for explicit and urgent population-specific conservation and management strategies to be developed and applied locally for common dolphins, considering that they rely on the region for important biological processes.
  相似文献   
140.
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