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171.
Summary. Equine lymphocyte antigen (ELA) gene frequencies were estimated for pacing and trotting Standardbred mares residing on a breeding farm in central Ohio. The ELA gene frequencies for Ohio Standardbreds did not differ significantly from the ELA gene frequencies of Kentucky Standardbreds, determined by Bailey (1983). No significant differences were found in the distribution of ELA class I antigens in horses with lower overall fertility or a history of abortion on the investigated breeding farm. Likewise, no significant association was observed when the ELA types of both the mare and the stallion to which she was mated were compared with the reproductive efficiency of the mare.  相似文献   
172.
PARK  DAVID 《Annals of botany》1959,23(1):35-49
From either a mycelial or a conidial inoculum the fungus survivedin soil as inactive chlamydospores. The level of its soil populationat equilibrium was too low to be studied by dilution plating.Plant materials placed on or beneath the surface of inoculatedsoil were colonized deeply by the fungus, which produced conidiaon them. Dispersal of conidia can occur with water movementin soil, and at right angles to, as well as in the directionof, that movement. No evidence was found of dispersal of thefungus in soil by continuous growth, even over continuous stretchesof organic matter. This finding was related to the inabilityof the fungus to colonize those organic materials that werepreviously colonized by other organisms from the soil, unlessits inoculum potential were greatly augmented. The fungus isthus seen to be a pioneer fungus. The strain used here grewoutwards a short distance from colonized organic food basesin the soil, leaving in the soil resting spores which couldcolonize fresh pieces of organic material subsequently addedthere. The organism could thus spread by discontinuous growthon successively available, fresh, organic materials.  相似文献   
173.
The distinctive feature of leaf‐rolling weevils is their special care for their progeny. In many species among the family Attelabidae, the female recognizes the size and shape of the leaf of the host‐plant and does the leaf cutting by a definite method. The location of cutting line, length and shape becomes the basic information in understanding the most fundamental structure of female's recognition process and cradle formation strategy. Leaf cutting is not only the process of withering the leaf by blocking the water flow along the main vein but also the process of making reversal easy at the leaf‐blade part. The difference in forms of cutting line, leaf blade, interval or dispersion of nibble marks on the stem and pitch of leaf rolling has effects on the shape of the completed cradle. In the present paper we provide leaf‐cutting patterns and the cradle formation process for 13 species of subfamily Apoderinae. We also provide a pictorial key of the cradle for the first time in Korea.  相似文献   
174.
Water uptake by Agave deserti and Ferocatus acanthodes was predictedusing a two-dimensional simulation model in which the soil arounda plant was divided into a series of layers and concentric cylindricalshells. Root lengths in 0.05 m thick soil layers were determinedfor both species in the field, where mean root depths were only0.11 m for A. deserti and 0.10 m for F. acanthodes. For a yearwith average precipitation (159 mm), 42 per cent of the annualprecipitation could be taken up by A. deserti and 25 per centby F. acanthodes. Predicted water uptake by both species wasgreater from the upper soil layers (above 0.15 m) for averageand dry years, but was greater from the deeper layers for awet year. The actual root distribution for both species ledto more water uptake than when all of the roots were in a singlelayer. The large number of days per year when the soil temperaturesexceeded 57 °C (the temperature for 50 per cent inhibitionof uptake of a vital stain by root cells) may exclude rootsfrom the 0.00–0.05 m soil layer, even though water uptakewhen all roots were located there was predicted to be maximal.Therefore, the observed root distribution of A. deserti andF. acanthodes may be limited near the soil surface by high temperaturesand at maximum depths by water availability for all but wetyears. Agave deserti, Ferocactus acanthodes, desert succulents, root system, root distribution, soil temperature, water uptake  相似文献   
175.
176.
Acid phosphatase (AP) in the egg of the lady beetle, Harmonia axyridis, was purified and characterized. Ammonium sulfate precipitation, CM column and isoelectrofocusing (IEF) were applied to purify an estimated molecular weight of 66 kDa AP. The purity was checked by SDS PAGE, native PAGE and Western blot. AP was detected in the hemolymph of the female and the egg, but not in the male on the blotting. Km of AP for a substrate, p‐nitrophenyl phosphate (p‐NPP), was 1.64 x 10‐4 M. AP had the optimum enzymatic activity at pH 3.5. In inhibition tests performed with various chemicals, ammonium molybdate suppressed 99% of the enzyme activity of AP even at the concentration of 5 x 10‐4 mM. AP was stable up to 50°C.  相似文献   
177.
People can eat a food without having a strong preference for it, and people can prefer a food without eating it. Given this seeming disconnect between attitude and behavior, which type of measure or segment can best be used to profile or identify loyal consumer segments of a food, such as soy? This research compares a usage‐based method (heavy‐light‐nonusers) with a new attitude‐based method (seeker‐neutral‐avoider), and finds that the attitude‐based method differentiates purchase‐related intentions better than the usage‐based method. Implications for profiling consumer taste patterns and consumer segments are provided.  相似文献   
178.
179.
A taxonomic study of the Korean Prostomidae is presented. Two species (Prostomis latoris Reitter, P. mordax Reitter) are recognized and P. mordax is reported for the first time in Korea. Comparison with type specimens was made. An illustration of the habitus and line drawings of diagnostic characters are provided.  相似文献   
180.
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