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371.
Matthew?Rocco?Price Julie?Anita Marie?Kruse M?Eric?Galvez Annaka?M?Lorincz Mauricio?Avigdor Paul?D?HeidemanEmail author 《Journal of circadian rhythms》2005,3(1):12
Background
Responsiveness to changing photoperiods from summer to winter seasons is an important but variable physiological trait in most temperate-zone mammals. Variation may be due to disorders of melatonin secretion or excretion, or to differences in physiological responses to similar patterns of melatonin secretion and excretion. One potential cause of nonphotoresponsiveness is a failure to secrete or metabolize melatonin in a pattern that reflects photoperiod length. 相似文献372.
Phosphorus (P) limitation in soil is a major concern for crop productivity. However, the use of chemical fertilizer is hazardous to the environment and costly. Therefore, the use of phosphate-solubilizing bacteria (PSB) is an eco-friendly approach for a sustainable agricultural system. In the present study, a field trial was conducted for two consecutive years to study the effects of three PSB strains isolated, Bacillus licheniformis, Pantoea dispersa, and Staphylococcus sp., with different P fertilizer rates on P uptake, P use efficiency (PUE), and grain yield of rice. The activities of soil enzymes were also studied in relation to PSB treatments. Comparative analysis of the yield and biochemical parameters revealed that inoculation of PSB consortium could reduce almost 50% of the recommended P dose in rice cultivation. Three PSB strains in combination with 50% P dose was most effective and showed the highest increases in P uptake and PUE as compared to the uninoculated control. Moreover, the PSB consortium combined with 50% P dose contributed to 50.58% and 35.64% yield increases compared to the uninoculated control for 2018 and 2019, respectively. Significant increases in the activities of soil dehydrogenase, alkaline phosphatase, and acid phosphatase were also recorded under PSB treatment. 相似文献
373.
Anita M. Glover 《Biological conservation》2008,141(6):1493-1504
Caves are an important resource to a large proportion of temperate bat species, primarily as mating and hibernation sites. However, information on bat use exists for only a small fraction of caves in many parts of the temperate world, in part because current survey methods are inappropriate for many species. We surveyed the UK’s largest karst landscape, the Yorkshire Dales, by monitoring autumn swarming (mating) activity at 53 caves using automated echolocation call loggers, followed by trapping. Over 60% of caves surveyed were used by bats, but there was considerable variation in activity. Swarming activity was positively correlated with chamber development and negatively correlated with the amount of water the cave carried: together these two predictors explained 45% of the variance. Entrance orientation and shelter explained a further 10%. Activity was not correlated with entrance size, altitude or connectivity to the nearest summer habitat. All five resident swarming species were caught at most sites: Myotis brandtii, Myotis daubentonii, Myotis mystacinus, Myotis nattereri and Plecotus auritus. Behaviour, species composition and sex and age ratios were typical of swarming reported in other studies. Bat populations and catchment sizes were large and despite the proximity of other suitable caves, bats showed high fidelity to single sites. Our results show that the national importance of these caves has been overlooked. We suggest that survey for swarming activity is a quick and effective method of identifying underground bat sites and is likely to uncover many previously unknown and important sites throughout the temperate world. 相似文献
374.
Adrian Bolliger Amarnadh Nalla Jakob Magid Andreas de Neergaard Anita Dole Nalla Thorkild C. Bøg-Hansen 《Soil biology & biochemistry》2008,40(4):887-893
Due to analytical similarities with the mycorrhizal glycoprotein glomalin, ubiquitous citrate and heat-extractable soil protein fractions have been assumed to be predominantly glomalin-stabilised within soil. Often termed glomalin-related soil protein (GRSP), little however is actually known of the “glomalin-purity” of these soil fractions. We undertook western and lectin blots and crossed immuno/lectin affinity electrophoresis (CIE/CLAE) analysis of “easily extractible” GRSP fractions, as well as liquid chromatography-tandem mass spectrometry (LC–MS/MS) of “total” GRSP fractions. To further test whether soil saprobes contribute to GRSP production, we amended soil with 14C-sucrose and examined whether 14C could be traced in the GRSP pool over a 500-day incubation period.While only four of six bands on SDS–PAGE profiles of easily extracted GRSP reacted with anti-glomalin MAb32B11 and the lectin Con A under our blotting conditions, CIE/CLAE indicated the presence of a single protein moiety in the easily extractible GRSP pool. LC–MS/MS analysis of total GRSP pooled from various soils also showed that although traces of protein tentatively assignable to soil bacteria were present in GRSP, their concentrations were low. Additionally, specific activity of total GRSP in 14C-labelled soil was relatively depleted compared to the bulk soil and soil microbial biomass. This suggests that little GRSP of heterotrophic origin was laid down over the incubation period, although the potential presence of a pre-existing 14C-free GRSP background, as well as of low microbial dynamics in the absence of any further substrate inputs to the soil warrant caution with this inference. 相似文献
375.
Kayodé AP Linnemann AR Hounhouigan JD Nout MJ van Boekel MA 《Journal of agricultural and food chemistry》2006,54(1):256-262
Seventy-six farmers' varieties of sorghum from Benin were distinguished by amplified fragment length polymorphism (AFLP) and clustered into 45 distinct genotypes. The genotype clusters were evaluated for their Fe, Zn, and phytate concentrations to assess the impact of genetic and environmental effects on the composition of the grains and to identify farmers' varieties with high potential Fe and Zn availability. The Fe concentration of the grains ranged from 30 to 113 mg/kg with an average of 58 mg/kg. The Zn concentration ranged from 11 to 44 mg/kg with an average of 25 mg/kg. The phytate concentration of the grain ranged from 0.4 to 3.5% with a mean of 1.2%. The grain-Fe and grain-Zn did not show consistent linkage to genetic variation, but varied significantly across field locations, suggesting a predominant environmental impact. The phytate concentration of the grains appeared to be environmentally as well as genetically determined. No varieties provide adequate Zn to meet nutritional requirements of sorghum consumers. The most promising varieties for Fe supply were tokogbessenou, mahi swan, biodahu, sa? ma?, mare dobi, sakarabokuru, and chabicouma, as they showed a [phytate]/[Fe] ratio of <14, which is the critical value above which Fe availability is strongly impaired. These varieties could therefore be recommended for the preparation of food products such as dibou, in which processing methods have only a slight diminishing effect on phytate levels. Further research is needed to test these varieties for the stability of [phytate]/[Fe] molar ratio across various environmental conditions. 相似文献
376.
377.
Characterization of the piRNA complex from rat testes 总被引:2,自引:0,他引:2
Lau NC Seto AG Kim J Kuramochi-Miyagawa S Nakano T Bartel DP Kingston RE 《Science (New York, N.Y.)》2006,313(5785):363-367