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81.
In a lichen sample collected from a tree in Bârlad town (Vaslui County, Romania), a new tardigrade species belonging to the genus Milnesium (granulatum group) was found. Milnesium berladnicorum sp. n. is most similar (in the type of dorsal sculpture) to Milnesium beasleyi Kaczmarek et al., 2012 but differs from it mainly by having a different claw configuration and some morphometric characters. Additionally, the new species differs from other congeners of the granulatum group by the different type of dorsal sculpture, claw configuration and some morphometric characters.  相似文献   
82.
Optical tissue clearing is a method allowing post‐mortem deep imaging of organs in three dimensions. By optimizing the CUBIC clearing protocol, the authors provide rapid and simple approach to clear the entire adult rat organism within as little as four days, which is accompanied by the variety of its staining and imaging techniques. The image was captured with polarizers and demonstrates transparent rodent heart with thread‐like crystals of clearing reagent. Further details can be found in the article by Pawe? Matryba et al. ( e201700248 ).

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83.
UPTAKE AND RELEASE OF TAURINE FROM RAT BRAIN SLICES   总被引:13,自引:8,他引:5  
Abstract— Rapid efflux of [35S]taurine from rat brain slices was observed on electrical stimulation. Slower release resulted when the Ca2+ content of the perfusion medium was replaced with Mg2+. Uptake of [35S]taurine into rat cortical slices was unaffected by GABA, glutamic acid, glycine and leucine but was inhibited by alanine, ouabain, KCN and 2,4-dinitrophenol. Of a number of analogues of taurine, 2-aminoethylsulphinic acid was the most potent in inhibiting the uptake of [35S]taurine. The rate of uptake was found to be decreased by lowering the incubation temperature. The possibility that taurine may be a neurotransmitter is discussed.  相似文献   
84.
Leptosphaeria maculans and L. biglobosa are closely related sibling fungal pathogens that cause phoma leaf spotting, stem canker (blackleg) and stem necrosis of oilseed rape (Brassica napus). The disease is distributed worldwide, and it is one of the main causes of considerable decrease in seed yield and quality. Information about the time of ascospore release at a particular location provides important data for decision making in plant protection, thereby enabling fungicides to be used only when necessary and at optimal times and doses. Although the pathogens have been studied very extensively, the effect of climate change on the frequencies and distributions of their aerially dispersed primary inoculum has not been reported to date. We have collected a large dataset of spore counts from Poznan, located in central-west part of Poland, and studied the relationships between climate and the daily concentrations of airborne propagules over a period of 17 years (1998–2014). The average air temperature and precipitation for the time of development of pseudothecia and ascospore release (July–November), increased during the years under study at the rates of 0.1 °C and 6.3 mm per year. The day of the year (DOY) for the first detection of spores, as well as the date with maximum of spores, shifted from 270 to 248 DOY, and from 315 to 265 DOY, respectively. The acceleration of the former parameter by 22 days and the latter by 50 days has great influence on the severity of stem canker of oilseed rape.  相似文献   
85.
Seabirds in the Arctic are known to link marine and terrestrial ecosystems. They feed in the sea and breed on land, where they deposit enormous amounts of guano. Soil in the vicinity of seabird colonies is much more enriched with nutrients as compared to areas beyond their impact, which positively affects primary and secondary production. Water bears (Tardigrada) are microinvertebrates which constitute a permanent and ubiquitous faunal component of polar regions. Here, we tested the influence of seabird guano on Tardigrada communities; we established two transects in Hornsund (SW Spitsbergen): (1) SEABIRD where little auks (Alle alle) nested, and (2) CONTROL, an area without a little auk colony. In total, we collected 160 moss, lichen and mixed (moss/lichen) samples from those areas. In total, we found 1990 specimens belonging to 32 taxa (25 identified to species level). The average density of water bears was higher in the SEABIRD transect (9.31 ind g?1), where mosses predominated over lichens, in comparison with the CONTROL transect (5.83 ind g?1), where more lichens occurred. Thus, ornithogenic enrichment of soil and locally facilitated development of mosses over lichens might be important factors responsible for the increase in invertebrate abundance. According to canonical correspondence analysis, the little auk colony effect explained 13.2 % of the tardigrade species composition, and this factor appeared to be more important than the vegetation type itself. Four taxa, i.e. Isohypsibius cf. reticulatus, Microhypsibius bertolanii, Minibiotus cf. formosus and Ramazzottius cf. rupeus, have been recorded in the Svalbard archipelago for the first time.  相似文献   
86.
87.
The 2C DNA values in 38 species and accessions of the genus Lupinus (Fabaceae) from the New World have been analysed using flow cytometry. They are representatives of North and South American species (the Atlantic and the Andean regions). Estimated 2C DNA values ranged from 1.08 pg in L. pusillus to 2.68 pg in L. albicaulis (both from North America), that is a variation of more than 2.5-fold. The variation for North American lupins was much higher than that for South American ones. Statistical analysis of the data resulted in a grouping that showed for North American lupins some correlation with the length of life cycle. Discussion concerns some aspects of the evolution of the genus.  相似文献   
88.
One-pot metal promoted reactions between salicylaldehyde and 4-methyl-1,3-phenylenediamine in the presence of metal salts acting as template agents yield zinc(II) salicylaldimine complexes containing N,N′-bis(salicylidene)-4-methyl-1,3-phenylenediamine (H2L) as a result of the [2 + 1] Schiff base condensation. The complexes of formula [Zn(HL)Cl(H2O)2] · C2H5OH and [Zn(H2L)2Cl(NO3)(H2O)] · CH3OH were characterized as powder solids and in solution by spectroscopic methods (IR, 1H and 13C NMR, FAB-MS, ESI-MS, UV-Vis), thermogravimetric and elemental analysis, potentiometry, and tested for antimicrobial activity against Staphylococcusaureus in a minimum inhibitory concentration (MIC) experiment. In these two powder solid species, the salicylaldimine, formed in a self-assembly process, acts in two different coordination modes: as monodeprotonated bidentate chelator with an N,O donor set or as a neutral monodentate using exclusively oxygen as the donor atom without involving the nitrogen atoms in the coordination. However, crystals of these two complexes are isomorphous, with 1:2 metal:ligand stoichiometry, and display the latter, relatively rare coordination pattern. In solution, the presence of a 1:1 complex of monodeprotonated state is only detected. The complexes exhibit antimicrobial activity against S.aureus.  相似文献   
89.
90.
The mechanomyographic (MMG) signal analysis has been performed during single motor unit (MU) contractions of the rat medial gastrocnemius muscle. The MMG has been recorded as a muscle surface displacement by using a laser distance sensor. The profiles of the MMG signal let to categorize these signals for particular MUs into three classes. Class MMG-P (positive) comprises MUs with the MMG signal similar to the force signal profile, where the distance between the muscle surface and the laser sensor increases with the force increase. The class MMG-N (negative) has also the MMG profile similar to the force profile, however the MMG is inverted in comparison to the force signal and the distance measured by using laser sensor decreases with the force increase. The third class MMG-M (mixed) characterize the MMG which initially increases with the force increases and when the force exceeds some level it starts to decrease towards the negative values. The semi-pennate muscle model has been proposed, enabling estimation of the MMG generated by a single MU depending on its localization. The analysis have shown that in the semi-pennate muscle the localization of the MU and the relative position of the laser distance sensor determine the MMG profile and amplitude. Thus, proposed classification of the MMG recordings is not related to the physiological types of MUs, but only to the MU localization and mentioned sensor position. When the distance sensor is located over the middle of the muscle belly, a part of the muscle fibers have endings near the location of the sensor beam. For the MU MMG of class MMG-N the deflection of the muscle surface proximal to the sensor mainly influences the MMG recording, whereas for the MU MMG class MMG-P, it is mainly the distal muscle surface deformation. For the MU MMG of MMG-M type the effects of deformation within the proximal and distal muscle surfaces overlap. The model has been verified with experimental recordings, and its responses are consistent and adequate in comparison to the experimental data.  相似文献   
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