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231.
Ohne Zusammenfassung 相似文献
232.
233.
The effect of two chemosterilant materials 5-fluoroorotic acid (FA) and 5-fluorouracil (FU) was studied on the predatory mite,Amblyseius gossipi (El-Badry) in the laboratory. Percentages of mortality for adult females ranged from 6.00 to 41.30% (FA) and from 3.00 to 28.70% (FU). Results showed that the number of eggs layed/female and egg hatchability of the mite were decreased when the two chemosterilants were used comparing with control, while liefe cycle and longivity were slightly decreased for both males and females. 相似文献
234.
Zusammenfassung Beobachtungen bei Zürich ergaben, daß Lepidopteren-Falter oft in der Lage sind, sich aus Spinnennetzen von Arten der Argiopidae und Tetragnathidae zu befreien. Lepidopteren machen nur einen sehr kleinen Teil der Nahrung dieser Spinnen aus. Diese Tatsache muß bei der Bewertung von Spinnen als Schädlingsfeinde mit berücksichtigt werden.
Mit einer Tabelle
Ausgeführt mit Unterstützung durch den schweizerischen Nationalfonds zur Förderung der Wissenschaftlichen Forschung. 相似文献
Some observations on the escape of adult Lepidoptera from webs of orb-weaving spiders
Field studies near Zurich (Switzerland) have shown, that adult Lepidoptera often are able to escape from spider webs of the families Argiopidae and Tetragnathidae. In the food of these orb-weaving spiders Lepidoptera made up only a very small part. The capability of the lepidopterans to escape from spider webs seems to be of great ecological importance.
Mit einer Tabelle
Ausgeführt mit Unterstützung durch den schweizerischen Nationalfonds zur Förderung der Wissenschaftlichen Forschung. 相似文献
235.
Dr. F. N. Zaki 《Journal of pest science》1986,59(2):34-36
Full-grown paralyzed larvae ofSpodoptera littoralis, Phthorimaea operculella andAnagasta kuebniella were used as preys for rearingChrysoperla canea larvae.P. operculella induced the shortest larval period, the lowest larval or pupal mortality, highest percent of emergence, longest adult longevity and maximum productivity. Using mature larvae ofS. littoralis gave intermediate values between those reported forP. operculella andA. kuebniella. 相似文献
236.
Dr. F. Kühlhorn 《Journal of pest science》1981,54(12):179-184
In connection with the consideration on the annual cycle and the population dynamics ofAnopheles messeae messeae Fall. in the surroundings of Munich/ West-Germany the effects of the different ecological conditions are discussed. The following factors and connexions are considered: the sphere of life of the larvae; the temperature of water and the pH beneath the surface of the biotopes during the period of development of the larvae; representatives of the accessary flora and fauna as possible booindicators and the importance of many of these species as factors of limitation for the larvae. A view is given of the annual cycle ofA. m. messeae and the possible causes for the considerable reduction of its population in the months after the maximum of July. Finally remarks are made on the higienical importance ofA. m. messeae. 相似文献
237.
Dr. A. M. Korayem 《Journal of pest science》1993,66(1):18-21
The effect of different levels of zinc fertilization applied by two methods on the growth and yield of rice infected with the rice-root nematode,Hirschmanniella oryzae was assayed under the field conditions. A positive correlation between zinc concentration and both rice grain yield andH. oryzae total population was found. Only the seed-soaking method of zinc application, significantly increased the rice growth and the nematode total population density. Increasing percentages of nematode total population and growth and grain rice yield caused by the soaking method were more than those of the second one. In case of the first method the nematode total population ofH. oryzae reached the peak 60 days after transplanting and then declined thereafter as the rice plants reached maturity. While, in case of the second method, the nematode total population reached the peak 90 days after transplanting as the rice plants reached maturity. 相似文献
238.
Dr. S. A. Temerak 《Journal of pest science》1984,57(3):54-56
Sesamia cretica larvae infected with the bacterium,Serratia marcescens orBacillus thuringiensis were exposed toBracon brevicornis females, separately and in combination with non-infected larvae in the laboratory. Host larvae were exposed to the parasitoid under two manipulations “the larvae still alive or dead completely”. Bracon brevicornis females could not absolutely discriminate between healthy and moribund larvae (due toB. t. orS. m.) when those larvae exposed in a live appearance separately or jointly. However, they could discriminate between dead larvae (due to parasitoid's venom) and dead larvae due to Bacteria (B. t. orS. m.). 相似文献
239.
The potential drivers in forming avian biodiversity hotspots in the East Himalaya Mountains of Southwest China 总被引:1,自引:0,他引:1 下载免费PDF全文
Little has been published to describe or interpret Asian biodiversity hotspots, including those in the East Himalayan Mountains of Southwest China (HMSC), thus making necessary a review of the current knowledge. The Pliocene and Pleistocene geological and glacial histories of the Asian continent differ from those of Europe and North America, suggesting different mechanisms of speciation and extinction, and, thus, different responses to climate changes during the Quaternary glaciations. This short review summarizes potential drivers in shaping and maintaining high species richness and endemism of birds in the HMSC. The geographical location at the junction of different biogeographical realms, the wide range of habitats and climates along the extensive elevational range, the complex topography and the distinct geological history of this region have probably contributed to the evolution of an exceptionally species‐rich and endemic‐rich, specialized montane avian fauna. The Mountain systems in the HMSC may have provided refugia where species survived during the glacial periods and barriers for preventing species dispersal after the glacial periods. More studies are required to further test this refugia hypothesis by comparing more cold‐tolerent and warm‐tolerent species. 相似文献
240.
Hydrated gluten, treated with various salts, was analyzed by near-infrared (NIR) spectroscopy to assess the ability of this method to reveal protein structure and interaction changes in perturbed food systems. The spectra were pretreated with second-derivative transformation and extended multiplicative signal correction for improving the band resolution and removing physical and quantitative spectral variations. Principal component analysis of the preprocessed spectra showed spectral effects that depended on salt type and concentration. Although both gluten texture and the NIR spectra were little influenced by treatment with salt solutions of low concentrations (0.1-0.2 M), they were significantly and diversely affected by treatment with 1.0 M salt solutions. Compared to hydration in water, hydration in 1.0 M sulfate salts caused spectral effects similar to a drying-out effect, which could be explained by salting-out. 相似文献