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571.
Differentiation between organic and conventional coffee has increased due to the growing demand and high consumption of healthy foods that contain compounds with antioxidant potential, which have been associated with the reduction of chronic diseases. We used organic and conventional coffee in powder 4% (w/w) and infusions 5%, 10% and 20% (w/v) incorporated in a commercial diet to test in vivo. The levels of chlorogenic acid, caffeine and trigonelline were determined by high performance liquid chromatography. The body weight, weight gain, food consumption, aberrant foci crypt, mucin depleted foci, stress biomarkers protein carbonyl and malondialdehyde, biochemical parameters and behavior of the rats were compared between the experimental and control groups within a framework of colon carcinogenesis. The organic coffee showed higher levels of chlorogenic acid, caffeine and trigonelline than conventional, however, this difference did not significantly affect behavior. The infusions had an antioxidant effect, reducing the levels of malondialdehyde; however, the biochemical parameters of the serum were not altered, and there was neither induction nor prevention of preneoplasic lesions.  相似文献   
572.
Genetic Resources and Crop Evolution - Cacao (Theobroma cacao L.) is among the most important cash crops in tropical countries. The existing cacao genetic diversity represents a key resource to...  相似文献   
573.
Journal of Plant Diseases and Protection - The mango seed weevil Sternochetus mangiferae (Fabricius) (Coleoptera: Curculionidae) was detected in Brazil in 2014, becoming a potential threat to mango...  相似文献   
574.
Methylxanthinic alkaloids and phenolic compounds are related to the therapeutic properties of Ilex paraguariensis infusions. Considering the known vascular tropism of xanthines, an aqueous extract (mate) and caffeine were evaluated on blood vessel formation, in connection with the analysis of those secondary metabolites, which was performed in young and mature leaf samples collected in three cultivation systems located in the southern region in Brazil (Santa Catarina State). Samples of young and mature leaves from a monoculture cultivation system (MC) showed the highest content of phenolic compounds (149.68 microg/mL, young leaves; 135.50 microg/mL, mature leaves) and caffeine (young leaves, 148.07 microg/mL; mature leaves, 244.63 microg/mL) as compared to samples from agroforesty (AF) and shaded-native (NT) cultures. Theophylline was not detected in samples by reverse phase-high performance liquid chromatography, and mature leaves showed lower theobromine amounts (11.46 microg/mL). Treatments performed with mate aqueous extract and caffeine (1.03-4.12 microM/disk) in the yolk sac vascular membranes of 2-day-old chick embryos revealed pro-vasculo- and angiogenic properties as well as embryonic growth enhancement. These findings, uncoupled from any detectable embryotoxic effect, suggest a potential therapeutic and/or prophylactic use in cardiovascular disorders for caffeine and related constituents of mate plant extracts, an issue that waits further studies.  相似文献   
575.
During the past 40 years colluvial and alluvial deposits have been used in Brazil as good indicators of regional landscape sensitivity to Quaternary environmental changes. In spite of the low resolution of most of the continental sedimentary record, geomorphology and sedimentology may favor palaeoenvironmental interpretation when supported by independent proxy data. This paper presents results obtained from pedostratigraphic sequences, in near-valley head sites of southern Brazilian highlands, based on geomorphologic, sedimentologic, micromorphologic, isotopic and palynologic data. Results point to environmental changes, with ages that coincide with Marine Isotopic Stages (MIS) 5b; 3; 2 and 1. During the late Pleistocene, although under temperatures and precipitation lower than today, the local record points to relatively wet local environments, where shallow soil-water saturated zones contributed to erosion and sedimentation during periods of climatic change, as during the transition between MIS 2 and MIS 1. Late Pleistocene events with ages that coincide with the Northern Hemisphere Younger Dryas are also depicted. During the mid Holocene, slope-wash deposits suggest a climate drier than today, probably under the influence of seasonally contrasted precipitation regimes. The predominance of overland flow-related sedimentary deposits suggests an excess of precipitation over evaporation that influenced local palaeohydrology. This environmental condition seems to be recurrent and explains how slope morphology had influenced pedogenesis and sedimentation in the study area. Due to relative sensitiveness, resilience and short source-to-sink sedimentary pathways, near-valley head sites deserve further attention in Quaternary studies in the humid tropics.  相似文献   
576.
Recent global assessments have shown the limited coverage of protected areas across tropical biotas, fuelling a growing interest in the potential conservation services provided by anthropogenic landscapes. Here we examine the geographic distribution of biological diversity in the Atlantic Forest of South America, synthesize the most conspicuous forest biodiversity responses to human disturbances, propose further conservation initiatives for this biota, and offer a range of general insights into the prospects of forest species persistence in human-modified tropical forest landscapes worldwide. At the biome scale, the most extensive pre-Columbian habitats across the Atlantic Forest ranged across elevations below 800 masl, which still concentrate most areas within the major centers of species endemism. Unfortunately, up to 88% of the original forest habitat has been lost, mainly across these low to intermediate elevations, whereas protected areas are clearly skewed towards high elevations above 1200 masl. At the landscape scale, most remaining Atlantic Forest cover is embedded within dynamic agro-mosaics including elements such as small forest fragments, early-to-late secondary forest patches and exotic tree monocultures. In this sort of aging or long-term modified landscapes, habitat fragmentation appears to effectively drive edge-dominated portions of forest fragments towards an early-successional system, greatly limiting the long-term persistence of forest-obligate and forest-dependent species. However, the extent to which forest habitats approach early-successional systems, thereby threatening the bulk of the Atlantic Forest biodiversity, depends on both past and present landscape configuration. Many elements of human-modified landscapes (e.g. patches of early-secondary forests and tree monocultures) may offer excellent conservation opportunities, but they cannot replace the conservation value of protected areas and hitherto unprotected large patches of old-growth forests. Finally, the biodiversity conservation services provided by anthropogenic landscapes across Atlantic Forest and other tropical forest regions can be significantly augmented by coupling biodiversity corridor initiatives with biota-scale attempts to plug existing gaps in the representativeness of protected areas.  相似文献   
577.
Andean Potato is a major crop for farmers in the Andes and represents an important gene pool for potato improvement. We present the population structure and genetic diversity of 88 Andigena accessions collected in Northwestern Argentina based on functional markers (25 SSR) distributed along 12 chromosomes. Polymorphic information content ranged from 0.40 to 0.87. A Bayesian approach, a Principal Coordinate Analysis and a Cluster Analysis revealed the presence of: I) a major group containing most of the Andean accessions and II) a smaller group including the out-group cv. Spunta and the sequenced genotype DM. Several group specific alleles were detected. AMOVA showed that 81% of the variability was within each group. Eleven of the SSRs analyzed are linked or within genes reported to regulate traits of nutritional and industrial interest. Additionally, the allelic variant of a photoperiod dependent tuberization regulator gene, StCDF1.2, was exclusively detected in accessions clustered in group II.  相似文献   
578.
The implementation of aquaponics systems has significantly increased in the last two decades, and several studies have reported on the technical, socioeconomic, and environmental ramifications in order to achieve sustainability in food production. The present study, however, aimed to perform a commercial-scale economic evaluation, using a model marine aquaponics production system with the halophyte Sarcocornia ambigua and the shrimp Litopenaeus vannamei cultivated in nutrient film technology (NFT) and biofloc technology (BFT) systems, respectively. To calculate phytotechnical and zootechnical indexes, we used recent studies available in the literature. Indicators of operational costs (total cost of production—TCP) and financial viability were calculated based on a cash flow horizon of 10 years. The proposed study estimated an initial investment of US$ 474,253.07, with annual TCPs around US$ 192,220.50, US$ 247,740.52, and US$ 223,482.65 years 1, 2 to 9, and 10, the different periods studied. Within these respective periods, the annual production of halophyte was 17,017, 23,286, and 18,808 kg, while marine shrimp production was 10,659, 14,586, and 11,781 kg. Based on these annual production numbers, the TCPs were US$ 4.75, US$ 4.03, and US$ 4.67 kg?1 for halophyte and US$ 10.45, US$ 14.43, and US$ 11.52 kg?1 for shrimp. Three sales prices were estimated per kilogram of halophyte produced and one fixed price per kilogram of shrimp produced. Only the highest selling price showed favorable indexes after testing sensitivities. Based on the above parameters, halophyte TCP was below sales value, i.e., reference price, with the possibility of increasing the price to “premium” level, indicating that this marine aquaponics production system was feasible for implementation in Brazil.  相似文献   
579.
This study evaluated the effects of short-term exposure to sublethal levels of nitrite on oxidative stress parameters and histology of juvenile Brazilian flounder Paralichthys orbignyanus. An assessment of fish recovery was also performed. Fish were exposed to 0.08 (control), 5.72, 10.43, and 15.27 NO2-N mg L?1 for 10 days followed by the same recovery time. Gill, liver, and muscle samples were collected after 1, 5, and 10 days of exposure and after recovery for the measurement of antioxidant capacity against peroxyl radicals (ACAP), glutathione-S-transferase (GST) activity, content of non-protein (NPSH) and protein thiols (PSH), and lipid peroxidation levels by thiobarbituric acid-reactive substances (TBARS) content. Nitrite exposure induced alterations which compromised the overall antioxidant system (reduced ACAP and GST activity) and enhanced oxidative damage in lipids and proteins. Increases in GST activity and NPSH and PSH contents were also demonstrated. The recovery period allowed for resumption of basal levels for all (treatment 5.72 NO2-N mg L?1) or some of the evaluated parameters (other treatments). In conclusion, exposure to nitrite concentrations from 5.72 to 15.27 NO2-N mg L?1 induced oxidative stress and antioxidant responses in juvenile Brazilian flounder. The 10-day recovery period was sufficient for a complete resumption of basal physiological condition of fish exposed to concentrations of up to 5.72 NO2-N mg L?1.  相似文献   
580.
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