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991.
Clinical, neuroimaging, and neuropathological findings of 2 cases of canine primary diffuse leptomeningeal gliomatosis are described. Magnetic resonance imaging and histopathological examination of the brain revealed diffuse leptomeningeal alterations with no parenchymal involvement. These cases share many similarities with the same disease in humans.  相似文献   
992.
Tropical Animal Health and Production - The objective of this study was to evaluate the effects of rumen-protected oil (soybean and palm oil) in supplements for beef cattle during the fattening...  相似文献   
993.
The visualization of the surface of biological samples using an atomic force microscope reveals features of the external relief and can resolve very fine and detailed features of the surface. We examined specimens from the skin of the amphibians Salamandra salamandra Linnaeus, 1758, Lyciasalamandra luschani basoglui Baran & Atatür, 1980 and Mesotriton alpestris Laurenti, 1768, and from the surface of pollen grains of the plant species Cyclamen graecum Link, 1835 and Cistus salviifolius Linnaeus, 1753, which exhibit certain interesting features, imaged at the nanoscale level. It is likely that the relief influences the attributes of the interfaces between the tissues and the environment. We found that the microsculpture increases in size the surface of the examined tissues and this might be particularly important for their performance in the field. Microsculpturing of amphibians' skin may affect water regulation, dehydration and rehydration, and cutaneous gas exchange. Pollen grain relief might affect the firmness of the contact between pollen surface and water droplets. High resolution imaging of the external relief showed that roughening might induce wetting and influence the water status of the specimens. In addition, roughness affects the radius of water droplets retained in between the projections of the external relief. Roughness of the tissues was highly correlated with their vertical distance, whereas surface distances were highly correlated with horizontal distances. By enabling a more detailed characterization of the external sculptures, through sophisticated techniques, a more comprehensive examination of the samples indicates similarities among different living tissues, originated from different kingdoms, which can be attributed to environmental conditions and physiological circumstances.  相似文献   
994.
Bone marrow-derived mesenchymal stem cells (BM-MSCs) are widely used in regenerative medicine in horses. Most of the molecular characterisations of BM-MSCs have been made at 20% O2, a higher oxygen level than the one surrounding the cells inside the bone marrow. The present work compares the lifespan and the tri-lineage potential of equine BM-MSCs expanded in normoxia (20% O2) and hypoxia (5% O2). No significant differences were found in long-term cultures for osteogenesis and adipogenesis between normoxic and hypoxic expanded BM-MSCs. An up-regulation of the chondrogenesis-related genes (COL2A1, ACAN, LUM, BGL, and COMP) and an increase of the extracellular sulphated glycosaminoglycan content were found in cells that were expanded under hypoxia. These results suggest that the expansion of BM-MSCs in hypoxic conditions enhances chondrogenesis in equine BM-MSCs.  相似文献   
995.
996.
    
  1. Understanding marine mammal distributions is essential for conservation, as it can help identify critical habitat where management action can be taken. The semi‐enclosed Gulf of Corinth, Greece, has been identified as an Important Marine Mammal Area by the International Union for Conservation of Nature (IUCN) Marine Mammal Protected Areas Task Force, based on the regular occurrence of odontocete populations. A 7‐year (2011–17) dataset of boat‐based surveys was used to model and predict the distribution of striped dolphins, Stenella coeruleoalba, common dolphins, Delphinus delphis, and common bottlenose dolphins, Tursiops truncatus, in the entire Gulf (2400 km2).
  2. Multiple geographic, bathymetric, oceanographic, and anthropogenic variables were incorporated in a combined generalized additive model and generalized estimation equation (GAM‐GEE) framework to describe dolphin occurrence and produce distribution maps.
  3. Modelling indicated that striped and common dolphins prefer deep waters (>300 m) in the central and southern part of the Gulf, whereas bottlenose dolphins prefer shallow waters (<300 m) and areas close to fish farms along the northern–central shore.
  4. Model‐based maps of the predicted distribution identified a preferred habitat encompassing most of the Gulf, also revealing: (i) hot spots of dolphin distribution covering about 40% of the Gulf's surface; (ii) an almost complete overlap of striped and common dolphin distribution, consistent with the hypothesis that common dolphins modified their habitat preferences to live in mixed species groups with striped dolphins; (iii) a clear partitioning of striped/common and bottlenose dolphin habitat; and (iv) the important role played by fish farms for bottlenose dolphins, consistent with studies conducted elsewhere in Greece.
  5. Evidence provided by this study calls for area‐specific and species‐specific management measures to mitigate anthropogenic impacts.
  相似文献   
997.
998.
    
Journal of Soils and Sediments - Irrigation or flooding events with riverine waters containing compounds such as surfactants, colloids, and dissolved organic carbon and plant growth will modify...  相似文献   
999.
    
  1. Wetlands are increasingly threatened by human activities worldwide. Genetic monitoring of associated wildlife provides valuable data to support their conservation. Waterbirds such as the wood stork (Mycteria americana) are good bioindicators of wetland disturbance and destruction.
  2. This study investigated past and contemporary levels of genetic diversity, differentiation and demographic processes in 236 wood storks from two major wetlands in Brazil in which breeding colonies are concentrated, using nine microsatellite loci and a 237‐bp untranslated fragment of the mitochondrial Control Region.
  3. Amapá populations (northern region) showed slightly higher levels of genetic diversity than Pantanal populations (central western region) and both populations had a low number of effective breeders.
  4. Results from assignment tests, F‐statistics, AMOVA, spatial and non‐spatial Bayesian clustering analyses support the hypothesis of gene flow among colonies within regions, but significant differentiation between regions.
  5. The better supported Bayesian coalescent models based on both markers indicated that the northern population exchanged migrants with unsampled populations, and that the central western population was founded by individuals from the north. Mitochondrial estimates revealed that the timing of population divergence broadly overlapped the Last Glacial Maximum (LGM), and that the central western population expanded more recently than the northern population.
  6. The results support the hypothesis that the coastal wetlands in northern Brazil remained stable enough to shelter large wood stork populations during the LGM and storks colonized freshwater wetlands in the central western region following deglacial warming.
  7. Conservation policies and protective measures should consider Amapá and Pantanal wood stork populations as genetically differentiated units and priority should be given to Amapá populations that represent the source gene pool. Continuous genetic monitoring of wood storks would help detect genetic signs of changes in demographic trends that may reflect alterations or degradation in wetlands.
  相似文献   
1000.
    
To evaluate the effect of different dietary lipids on zebrafish reproduction, we examined parameters including ovary and carcass composition, oestradiol (E2) levels, eclosion rate and embryonic development. In our study, zebrafish were subjected to a 5‐month feeding trial whereby olive (OLV), linseed (LIN), fish (FIS) or corn (CRN) oil were used to compose four isonitrogenous and isoenergetic diets. A positive correlation was found between ovary EPA and whole‐body E2 concentration (= 0.005). The developmental dynamics was affected by dietary lipids and embryos from CRN treatment females; which had higher percentage of ARA in ovary (1.48 ± 0.44%) (= 0.015), developed faster at 8–9 h postfertilization (hpf) than the ones originated from females receiving other diets (= 0.0069). This effect was not sustained during later observation periods, suggesting ARA may act as a modulator of developmental dynamics only during initial phases. There was no clear effect of dietary lipid source on ovary protein content (= 0.304) and eclosion rates at 72 hpf (P = 0.0623). Dietary fatty acids play an important role in reproductive outcome; however, additional studies are necessary to elucidate the mechanisms by which HUFA affect embryonic development.  相似文献   
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