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101.
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This study reports a cross-modal, olfactory/visual event related potential (ERP) using odours as olfactory primes. The results show a difference in the ERP waveform for the N400 waveform when a visual image does not match the priming odour. An N400 peak was produced for both the matched and mismatched conditions but the peaks were significantly more negative for the mismatched condition. By the use of non-food odours this study extends an earlier finding by Grigor, who, using the same ERP paradigm, obtained similar results for food odours and photographs of food. 相似文献
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V. N. Orlov Yu. M. Borisov E. V. Cherepanova O. O. Grigor’eva A. G. Shestak V. B. Sycheva 《Russian Journal of Genetics》2012,48(1):70-78
The contact zone between Moscow and Western Dvina chromosomal races of common shrew Sorex araneus L. at the south of the Valdai Hights was traced over a distance of 20 km. Within this, close to parapatric, contact zone
of chromosomal races the width of sympatry zone was about 500 m (the narrowest among currently known hybrid zones), and the
proportion of hybrids was 24.3%. It was shown that in bimodal hybrid zones between chromosomal races of common shrew the width
of sympatry zones varied from 0.5 to 13 km. This width does not correlate with the cytogenetic features of the hybrids, and
seems to be determined by competitive relations between the races. The hybrid proportion is determined by the type of hybrid
heterozygosity, and decreased in the race sympatry zone from 33–40 to 21.5–25.2%. The decrease of the hybrid proportion can
be associated with the abnormal fertility of either the first generation, or the backcross hybrids. 相似文献
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A. N. Antimonova N. I. Petrenko E. E. Shults Yu. F. Polienko M. M. Shakirov I. G. Irtegova M. A. Pokrovskii K. M. Sherman I. A. Grigor’ev A. G. Pokrovskii G. A. Tolstikov 《Russian Journal of Bioorganic Chemistry》2013,39(2):181-185
Interaction of betulonic acid chloride with 4-amino-2,2,6,6-tetramethylpiperidine-1-oxyl, 3-amino-2,2,5,5-tetramethylpyrrolidine-1-oxyl, and 3-aminomethyl-2,2,5,5-tetramethylpyrrolidine-1-oxyl yielded the corresponding triterpene amides. The synthesized derivatives of betulonic acid were shown to exhibit a cytotoxic activity on models of the CEM-13, U-937, and MT-4 tumor cells. The concentration of the most active N-[3-oxo-28-norlup-20(29)-en-17-carbamoyl-(2,2,6,6-tetramethylpiperidine-4-yl)-1-oxyl that inhibited survival of the tumor cells by 50% (CCID50) proved to be 5.7–33.1 μM. 相似文献
108.
This paper studies how exposure conditions affect the trophic activity of Daphnia crustaceans and their sensitivity to heavy metals. To register the trophic activity of crustaceans, the change in intensity of the zero level of rapid fluorescence in chlorella alga utilized as feed is used. The optimal conditions (stocking density, age of test organisms, feeding schedule, and exposure time) are determined under which a high level of the trophic activity and sensitivity of crustaceans to pollution are registered. An experimental design is suggested in which crustaceans are first exposed to a toxicant and then a suspension of the alga is introduced into a cultivation medium. 相似文献
109.
T. N. Nazina A. A. Grigor’yan N. M. Shestakova T. L. Babich V. S. Ivoilov Qingxian Feng Fangtian Ni Jianqiang Wang Yuehui She Tingsheng Xiang Zhibin Luo S. S. Belyaev M. V. Ivanov 《Microbiology》2007,76(3):287-296
The physicochemical conditions and microbiological characteristics of the formation waters of the Kongdian oilfield of the Dagang oilfield (China) were studied. It was demonstrated that this oilfield is a high-temperature ecosystem with formation waters characterized by low mineralization. The concentrations of nitrogen and phosphorus compounds, as well as of electron acceptors, are low. Oil and oil gas are the main organic matter sources. The oilfield is exploited with water-flooding. The oil stratum was inhabited mostly by anaerobic thermophilic microorganisms, including fermentative (102–105 cells/ml), sulfate-reducing (0–102 cells/ml), and methanogenic (0–103 cells/ml) microorganisms. Aerobic bacteria were detected mainly in the near-bottom zone of injection wells. The rate of sulfate reduction varied from 0.002 to 18.940 μg S2? l?1 day?1 and the rate of methanogenesis from 0.012 to 16.235 μg CH4 l?1 day?1. Microorganisms with great biotechnological potential inhabited the oilfield. Aerobic thermophilic bacteria were capable of oxidizing oil with formation of biomass, the products of partial oxidation of oil (volatile acids), and surfactants. During growth on the culture liquid of oil-oxidizing bacteria, methanogenic communities produced methane and carbon dioxide, which also had oil-releasing capabilities. Using various labeled tracers, the primary filtration flows of injected solutions at the test site were studied. Our comprehensive investigations allowed us to conclude that the method for microbial enhancement of oil recovery based on the activation of the stratal microflora can be applied in the Kongdian oilfield. 相似文献
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