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991.
A 12-year-old, neutered female, Siberian Husky dog presented with a hind limb weakness of one month duration. To facilitate making a diagnosis multiple imaging modalities were performed. These modalities included radiography, ultrasonography, magnetic resonance imaging (MRI), magnetic resonance angiography (MRA) and selective angiography of the abdominal aorta. In this dog, the MRI/MRA studies provided the first documentation of the external iliac thrombi and the collateral circulation via the lumbar arteries. At necropsy, an aortoiliac thrombus caused by a mineralized arteriosclerotic plaque was noted.  相似文献   
992.
Peru has 103 taxa of wild potatoes (species, subspecies, varieties, and forms) according to Hawkes (1990; modified by us by a reduction of species in theSolanum brevicaule complex) and including taxa described by C. Ochoa since 1989. Sixty-nine of these 103 taxa (67% ) were unavailable from any of the world’s genebanks and 85 of them (83%) had less than three germplasm accessions. We conducted a collaborative Peru (INIA), United States (NRSP-6), and International Potato Center (CIP) wild potato (Solanum sect.Petota) collecting expedition in Peru to collect germplasm and gather taxonomic data. This is the first of a series of planned expeditions from 1998–2002. We collected from February 18 to April 18, 1998, in the southern departments of Apurímac, Arequipa, Cusco, Moquegua, Puno, and Tacna. We made 57 germplasm collections, including 14 taxa that are the first available as germplasm for any country (Solanum aymaraesense, S. chillonanum, S. incasicum, S. megistacrolobum subsp.megistacrolobum f. purpureum, S. longiusculus, S. multiflorum,S. pillahuatense, S. sawyeri, S. sandemanii, S. tacnaense, S. tarapatanum, S. urubambae, S. velardei, S. villuspetalum), and two additional taxa that are the first available for Peru but with germplasm from Bolivia (S. megistacrolobum subsp.toralapanum, S. yungasense). Collections also were made for the rare taxaS. acroscopicum, S. buesii, S. limbaniense, andS. santolallae. Our collections suggest the following minimum synonymy may be needed for Peruvian potatoes:S. sawyeri as a synonym ofS. tuberosum;S. hawkesii andS. incasicum as synonyms ofS. raphanifolium;S. multiflorum andS. villuspetalum as synonyms ofS. urubambae.  相似文献   
993.
To select the best microalgae for Ostrea edulis conditioning, four single species diets were fed to batches of broodstock, which were then compared using physiological and biochemical approaches. Ingestion and absorption were first studied, showing that Chaetoceros gracilis and Skeletonema marinoï were efficiently ingested (4.9–5.3 mg g?1 h?1) and absorbed (1.9–2.5 mg g?1 h?1) while Tetraselmis suecica led to the lowest physiological responses (0.36 and 0.12 mg g?1 h?1 respectively). When O. edulis were fed any microalgae except T‐ISO with only 79 mg g?1, gonads accumulated carbohydrates from 116 to 141 mg g?1 and the extent of accumulation depended on the species supplied in the order T. suecica<C. gracilis<S. marinoï. When oysters were fed either of the diatoms (C. gracilis or S. marinoï), an efficient transfer of 20:5(n‐3) to all tissues, including the gonads, was recorded while no enrichment in 22:6(n‐3) occurred in all tissues (polar fraction) when oysters were fed T‐ISO. In contrast (22:5(n‐6)), a characteristic fatty acid of T‐ISO accumulated in all tissues, confirming its allocation despite particularly low ingestion (1.66 mg g?1 h?1) and absorption (0.32 mg g?1 h?1). When oysters were fed C. gracilis or S. marinoï an efficient transfer of cholesterol and campesterol from diatoms to the gonads was observed, while no sterol accumulation occurred in the gonad when fed T. suecica. Because of low ingestion, absorption and poor biochemical compounds' transfer, T. suecica is not recommended for O. edulis conditioning. T‐ISO also exhibited low physiological performances but due to a specific 22:6(n‐3) enrichment in the gonad neutral fraction (16.1%), its potential role in reproduction should be considered. Chaetoceros gracilis is highly recommended for O. edulis broodstock while a source of DHA other than that provided by T‐ISO should be found due to its poor absorption. Because a mixed diet has been shown to be more efficient for O. edulis broodstock conditioning, complementary trials dealing with the effects of other species rich in 22:6(n‐3) such as Rhodomonas salina or Pavlova lutheri should be performed.  相似文献   
994.
995.
We determined how varying stocking density and food ration can influence the growth, mortality and biomass return of abalone raised in slab tanks. The abalone used were 2- year-old hybrids of Haliotis laevigata and Haliotis rubra . The experimental design involved replicate tanks and three levels of each factor (normal practice and ±20% density or food ration). Although increasing density from that typically used in farm practices reduced the growth rate by roughly 6%, biomass return increased by 15.5%, over the 9-month period. Increasing feed ration by 20% boosted biomass by significantly increasing abalone growth during the first 3 months by 4%, but was less effective as the animals grew. Growth, mortality and food conversion ratios were optimized in tanks with a low density and a low feed ration, but economic gains were dominated by the increased biomass return from tanks with a higher stocking density. It is thought that reduced dissolved oxygen and differing access to food contributed to the patterns observed.  相似文献   
996.
A popular species for food and sport, the European catfish (Silurus glanis) is well‐studied in its native range, but little studied in its introduced range. Silurus glanis is the largest‐bodied freshwater fish of Europe and is historically known to take a wide range of food items including human remains. As a result of its piscivorous diet, S. glanis is assumed to be an invasive fish species presenting a risk to native species and ecosystems. To assess the potential risks of S. glanis introductions, published and ‘grey’ literature on the species’ environmental biology (but not aquaculture) was extensively reviewed. Silurus glanis appears well adapted to, and sufficiently robust for, translocation and introduction outside its native range. A nest‐guarding species, S. glanis is long‐lived, rather sedentary and produces relatively fewer eggs per body mass than many fish species. It appears to establish relatively easily, although more so in warmer (i.e. Mediterranean) than in northern countries (e.g. Belgium, UK). Telemetry data suggest that dispersal is linked to flooding/spates and human translation of the species. Potential impacts in its introduced European range include disease transmission, hybridization (in Greece with native endemic Aristotle’s catfish [Silurus aristotelis]), predation on native species and possibly the modification of food web structure in some regions. However, S. glanis has also been reported (France, Spain, Turkmenistan) to prey intensively on other non‐native species and in its native Germany to be a poor biomanipulation tool for top‐down predation of zooplanktivorous fishes. As such, S. glanis is unlikely to exert trophic pressure on native fishes except in circumstances where other human impacts are already in force. In summary, virtually all aspects of the environmental biology of introduced S. glanis require further study to determine the potential risks of its introduction to novel environments.  相似文献   
997.
Relative abundance of many shark species in the Atlantic is assessed by compiling data from several independently conducted, but somewhat spatially limited surveys. Although these localized surveys annually sample the same populations, resulting trends in yearly indices often conflict with one another, thereby hindering interpretation of abundance patterns at broad spatial scales. We used delta‐lognormal generalized linear models (GLMs) to generate indices of abundance for seven Atlantic coastal shark species from six fishery‐independent surveys along the US east coast and Gulf of Mexico from 1975 to 2014. These indices were further analysed using dynamic factor analysis (DFA) to produce simplified, broad‐scale common trends in relative abundance over the entire sampled distribution. Effects of drivers including the North Atlantic Oscillation index, the Atlantic Multidecadal Oscillation index, annually averaged sea surface temperature and species landings were evaluated within the DFA model. The two decadal oscillations and species landings were shown to affect shark distribution along south‐east US coast. Estimated common trends of relative abundance for all large coastal shark species showed similar decreasing patterns into the early 1990s, periods of sustained low index values thereafter and recent indications of recovery. Small coastal shark species exhibited more regional variability in their estimated common trends, such that two common trends were required to adequately describe patterns in relative abundance throughout the Gulf of Mexico and Atlantic. Overall, all species’ (except the Gulf of Mexico blacknose shark) time series concluded with an increasing trend, suggestive of initial recovery from past exploitation.  相似文献   
998.
A study of the availability of pesticide-treated seed on arable fields was performed. The research was carried out in three different areas of The Netherlands (soil types ranging between sand and heavy clay) and included the following topics: drilling techniques, soil conditions, location on the field and spillage. The results show that there is a large variation among the various crops in the percentage of seed remaining on the soil surface. This is mainly caused by differences in drilling techniques and soil conditions. The percentage of surface seeds after standard drilling is approximately four times higher than after precision drilling. The best correlation for the impact of soil conditions was found for the overall measure of clod weight. Large differences in seed densities (factor of 3.5) were found between the headland and the field centre. Spillage occured in most crops investigated, with an average of two spills per field. Based on the field data it is recommended to use in the current risk assessment for birds and mammals the following percentages of seed remaining on the soil surface: 0.5% for precision drilling, 3.3% for standard drilling in spring and 9.2% for standard drilling in autumn.  相似文献   
999.
The variability in commercial corn hybrids for corn fiber yields, amounts of extractable oil, and levels of individual and total phytosterol components in corn fiber oil was determined. Also, the effect of growth location on fiber yields, fiber oil content, and the levels of individual and total phytosterol compounds was determined. Significant variation was observed in the commercial hybrids for fiber yield (13.2–16.6%) and fiber oil yield (0.9–2.4%). No significant correlation was observed between fiber and oil yields. Significant variations in the commercial corn hybrids were also observed in the individual phytosterol compounds in corn fiber oil: 2.9–9.2% for ferulate phytosterol esters (FPE); 1.9–4.3% for free phytosterols (St); and 6.5–9.5% for phytosterol fatty acyl esters (St:E). Positive correlations were observed among the three phytosterol compounds in the corn fiber oil (R = 0.75 for FPE and St:E; 0.48 for St:E and St; and 0.68 for FPE and St). The effect of location on dependent variables was also significant. The same hybrids grown at different locations showed a variation (range) of 4.0–17.5% for FPE, 4.9–12.2% for St:E, and 1.95–4.45% for St. Relative ranking of hybrids with respect to phytosterol composition was consistent for almost all of the growth locations.  相似文献   
1000.
Breadmaking quality in wheat is one of several considerations that plant breeders face when developing new cultivars. In routine breeding programs, quality is assessed by small-scale dough-handling and bake tests, and to some extent, by biochemical analysis of gluten proteins. An alternative, not yet fully examined, method for wheat flour quality assessment is near-infrared reflectance (NIR) spectrophotometry. The present study was performed on 30 genotypes of hard red winter wheat grown during two crop years at eight to nine locations in the Great Plains area of the United States. Biochemical testing consisted of measuring protein fractions from size-exclusion HPLC (M r > 100k, M r 25–100k, and M r < 25k designated as glutenin, gliadins, and albumin and globulins, respectively), pentosan content, and SDS sedimentation volume. Dough-handling properties were measured on a mixograph and recorded as the time to peak dough development, the peak resistance, the width of the mixing curve, and the width of the curve at 2 min past peak. Partial least squares analyses on diffuse NIR spectra (1,100–2,498 nm) were developed for each constituent or property. When applied to a separate validation set, NIR models for glutenin content, gliadin content, SDS sedimentation volume, and mixograph peak resistance demonstrated reference vs. predicted correlations ranging from r = 0.87 to r = 0.94. Such models were considered sufficiently accurate for screening purposes in breeding programs. NIR spectra were responsive to each constituent or property at a level higher than expected from a correlation between the constituent or property and protein content (recognizing that protein content is modeled by NIR with high accuracy).  相似文献   
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