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581.
Ozaki M Wada-Katsumata A Fujikawa K Iwasaki M Yokohari F Satoji Y Nisimura T Yamaoka R 《Science (New York, N.Y.)》2005,309(5732):311-314
In animal societies, chemical communication plays an important role in conflict and cooperation. For ants, cuticular hydrocarbon (CHC) blends produced by non-nestmates elicit overt aggression. We describe a sensory sensillum on the antennae of the carpenter ant Camponotus japonicus that functions in nestmate discrimination. This sensillum is multiporous and responds only to non-nestmate CHC blends. This suggests a role for a peripheral recognition mechanism in detecting colony-specific chemical signals. 相似文献
582.
Banks JA Nishiyama T Hasebe M Bowman JL Gribskov M dePamphilis C Albert VA Aono N Aoyama T Ambrose BA Ashton NW Axtell MJ Barker E Barker MS Bennetzen JL Bonawitz ND Chapple C Cheng C Correa LG Dacre M DeBarry J Dreyer I Elias M Engstrom EM Estelle M Feng L Finet C Floyd SK Frommer WB Fujita T Gramzow L Gutensohn M Harholt J Hattori M Heyl A Hirai T Hiwatashi Y Ishikawa M Iwata M Karol KG Koehler B Kolukisaoglu U Kubo M Kurata T Lalonde S Li K Li Y Litt A Lyons E Manning G Maruyama T Michael TP 《Science (New York, N.Y.)》2011,332(6032):960-963
583.
Kazuaki Hiramatsu Yuji Oshima Suguru Inoue Shiomi Shikasho 《Paddy and Water Environment》2005,3(2):79-92
The environmental behavior and fate of tributyltin (TBT) in the northern Ariake Sea, resulting from the use of TBT-containing
antifouling paints on hulls of ships, pleasure crafts and docking facilities, was assessed by numerical simulations. First,
a mathematical model was devised on the basis of a non-steady state equilibrium, one box multi-compartment model consisting
of the surface micro-layer, the water column, the mud-layer, and the bottom sediment compartments. The movement of TBT among
the four compartments was modeled by resuspension of bottom mud, deposition of suspended sediment, film penetration and water
advection in each compartment. Furthermore, a one-dimensional diffusion equation was introduced into the bottom sediment compartment
to calculate profile distribution of TBT. The reactivity of TBT considered within the compartments included biological degradation,
adsorption to particulate matter and diffusion. Next, the optimal amount of past TBT loads, reflecting the recent observations
of TBT concentration in the waters and sediments of the northern Ariake Sea, was searched by a simple genetic algorithm. The
relative sensitivity of various model parameters were also determined to identify the more important parameters for estimating
the environmental behavior and fate of TBT. Finally, the future status of TBT contamination of the northern Ariake Sea was
predicted assuming the discontinued use of TBT-containing antifouling paints. Despite its simple model structure relative
to hydraulics, it was concluded that this multi-compartment model adequately estimated the environmental behavior and fate
of TBT. 相似文献
584.
Tetsuya KOMATSU Erina YOSHIDA Ayumi SHIGENAGA Nozomi YASUIE Shintaro UCHIYAMA Yuji TAKAMURA Kennosuke SUGIE Kumiko KIMURA Makoto HARITANI Tomoyuki SHIBAHARA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(7):1113
One calf died (No. 1) and another was euthanized following astasia (No. 2). Histopathological examination revealed suppurative meningoencephalitis in these calves. Klebsiella pneumoniae antigens were detected in lesions. Thymocytes were decreased in the thymus cortex in both cases. 16S rRNA gene sequencing of the No. 1 isolate and bacterial extracts from formalin fixed paraffin embedded sections of No. 2 revealed that both samples were K. pneumoniae. The No. 1 isolate showed multidrug resistance against penicillin antibiotics, fosfomycin, streptomycin, macrolide antibiotics, tetracycline antibiotics, and clindamycin. Immunosuppression is a significant septicemic K. pneumoniae infection risk factor. Our study provides new aspects regarding K. pneumoniae infections in cattle, bacterial meningoencephalitis differentiation, and K. pneumoniae and bacterial meningoencephalitis treatments. 相似文献
585.
586.
Sakai H Tsushima Y Nagasawa H Ducusin RJ Tanabe S Uzuka Y Sarashina T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(1):125-127
The prevalence of Cryptosporidium infection was examined in 480 healthy cattle (0-39 months old) in the Tokachi district in Hokkaido during the period from June to September in 2000 and from June to July in 2001. C. parvum oocysts were detected in 6 of 50 cattle (0-2 months old) in 2001; while C. muris was detected in 2 of 56 cattle (6-8 months old) in 2001, in 1 of 15 cattle (9-11 months old) in 2001, in 1 of 88 cattle (15-17 months old) in 2000, in 4 of 89 cattle (18-21 months old) in 2000 and in 2 of 53 cattle (21-23 months old) in 2000. 相似文献
587.
This study was conducted to determine the microbial biomass carbon and abundance and diversity of soil microorganisms immediately
after the occurrence of fire in a Japanese red pine forest, and to determine the pattern of microbial recovery within the
first year after fire. The effects of fire at three slope positions were also determined. Three plots in each of the burnt
and unburnt areas, measuring 10 × 10 m, were established. The first plot was located at the valley bottom, the second plot
was located at the middle slope, and the third plot was located at the ridge. Analysis showed that for all parameters studied,
the three plots in the unburnt area did not differ significantly and so they were treated as one control plot. The microbial
biomass, abundance, and diversity structure in the unburnt and burnt plots showed significant differences. The unburnt area
had the highest biomass carbon, abundance, and diversity, followed by the valley bottom, the middle slope, and then the ridge
in the burnt area, and significant differences in the burnt plots were found between the valley bottom, the middle slope,
and the ridge. The microbial diversity in the burnt area differed from that of the unburnt area, the microbial diversity being
significantly lower in the burnt area, and the ridge was shown to have been the most affected by fire. 相似文献
588.
Inagawa K Seki S Bannai M Takeuchi Y Mori Y Takahashi M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(10):1063-1066
gamma-aminobutyric acid (GABA, 30 mg/kg) was administered to aged dogs with recent history of veterinary clinic visits (mean age: 15.3 years old) once daily for 2 weeks by mixing with food. Their owners subjectively evaluated the effects of GABA on behavioral signs often associated with aging in the dogs. Improvement in some of behavioral signs was notable without any observable adverse effects. Dogs administered with GABA tended to exhibit improvement in emotional states and signs may be caused by neurovegetable dysfunction, though effects on cognitive dysfunction syndrome were not always observed. Thus, GABA administration may be one of the effective means of improving the quality of life of aged dogs. 相似文献
589.
590.
不同秸秆还田方式对旱地红壤细菌多样性及群落结构的影响 总被引:3,自引:0,他引:3
为明确不同秸秆还田方式下土壤细菌群落结构变化特征,以南方典型旱地红壤为研究对象,基于中国科学院鹰潭红壤生态实验站玉米单作系统不同秸秆还田方式的长期试验,利用高通量测序明确了不同秸秆还田方式对土壤细菌多样性及群落结构的影响。结果表明:1)秸秆还田对土壤肥力提升显著,以秸秆猪粪配施(NPKSM)提升效果最佳;2)常规化肥处理(NPK)对细菌多样性无显著影响,但秸秆还田(NPKS)、秸秆猪粪配施(NPKSM)以及生物质炭(NPKB)处理均显著提升土壤细菌多样性;3)速效磷(AP)和土壤有机碳(SOC)变化是影响细菌多样性指数的主要因素,而速效钾(AK)、pH、总磷(TP)以及总氮(TN)均显著驱动细菌群落结构变异。研究结果从培育红壤肥力与微生物多样性的角度,为农业生态系统生物功能和土壤健康的协同提升提供了科学依据。 相似文献