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11.
A Philipp A Schneider I V?srik K Finke Y Xiong D Beach K Alitalo M Eilers 《Molecular and cellular biology》1994,14(6):4032-4043
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Karina Reiter Christoph Plutzar Dietmar Moser Philipp Semenchuk Karl-Heinz Erb Franz Essl Andreas Gattringer Helmut Haberl Fridolin Krausmann Bernd Lenzner Johannes Wessely Sarah Matej Robin Pouteau Stefan Dullinger 《Global Ecology and Biogeography》2023,32(6):855-866
Aim
Land use is the most pervasive driver of biodiversity loss. Predicting its impact on species richness (SR) is often based on indicators of habitat loss. However, the degradation of habitats, especially through land-use intensification, also affects species. Here, we evaluate whether an integrative metric of land-use intensity, the human appropriation of net primary production, is correlated with the decline of SR in used landscapes across the globe.Location
Global.Time period
Present.Major taxa studied
Birds, mammals and amphibians.Methods
Based on species range maps (spatial resolution: 20 km × 20 km) and an area-of-habitat approach, we calibrated a “species–energy model” by correlating the SR of three groups of vertebrates with net primary production and biogeographical covariables in “wilderness” areas (i.e., those where available energy is assumed to be still at pristine levels). We used this model to project the difference between pristine SR and the SR corresponding to the energy remaining in used landscapes (i.e., SR loss expected owing to human energy extraction outside wilderness areas). We validated the projected species loss by comparison with the realized and impending loss reconstructed from habitat conversion and documented by national Red Lists.Results
Species–energy models largely explained landscape-scale variation of mapped SR in wilderness areas (adjusted R2-values: 0.79–0.93). Model-based projections of SR loss were lower, on average, than reconstructed and documented ones, but the spatial patterns were correlated significantly, with stronger correlation in mammals (Pearson's r = 0.68) than in amphibians (r = 0.60) and birds (r = 0.57).Main conclusions
Our results suggest that the human appropriation of net primary production is a useful indicator of heterotrophic species loss in used landscapes, hence we recommend its inclusion in models based on species–area relationships to improve predictions of land-use-driven biodiversity loss. 相似文献15.
Walter K. F. Seelentag Ursula Günthert Parvin Saremaslani Eva Futo Madeleine Pfaltz Philipp U. Heitz Jürgen Roth 《Histochemistry and cell biology》1996,106(3):283-289
CD44 isoforms have been implicated in tumor progression and metastasis formation. This study presents a thorough immunohistochemical
analysis of CD44 standard and isoform expression in normal human skin appendages and epidermis applying monoclonal antibodies
against CD44s, CD44v3, -v4, -v5, -v6, and -v9. An improved immunohistochemical protocol with microwave-based antigen retrieval
in paraffin sections and heavy metal amplification of the diaminobenzidine reaction product provided enhanced resolution and
sensitivity as compared to studies on frozen sections. The hair follicle, the seborrheic and eccrine sweat glands were strongly
positive for all CD44 isoforms studied. In the latter, the clear cells but not the dark (intercalated) cells were positive.
The sudoriferous ducts adjacent to the glands were weakly positive for all CD44 isoforms and strongly positive near the skin
surface. In the apocrine glands, the basal cells showed only a moderate positivity. The myoepithelial cells expressed only
CD44s. In the epidermis, all CD44 isoforms were detectable, with strongest CD44 immunostaining in the lower third of the stratum
spinosum and weaker staining in the stratum basale and the upper two-thirds of the stratum granulosum. The stratum granulosum
and corneum were unreactive. Thus, a regional and cell type-specific CD44 expression was revealed.
Accepted: 10 May 1996 相似文献
16.
Johannes E. Philipp 《Radiation and environmental biophysics》1984,23(4):295-297
Summary In the above mentioned article [1] the notion of a time-dependent Gibbs free energy has been introduced to explain the observed time-pattern of embryo growth in seeds. Furthermore, the notion of a non-random thermal communication has been inferred from an inspection of the shapes of germination time distributions. It can be shown, however, that the reasoning leading to the time-dependent thermodynamic potential is based on inappropriate interpretation of kinetic equations, and that the shape of the distributions of germination time might be a natural consequence of the initial distribution of embryo size in the seeds.Discussion about the Paper Seed Germination as a Thermobiological Problem by L. G. Labouriau Radiation and Environmental Biophysics 15:345–366 (1978) 相似文献
17.
Marianne Philipp 《Ecography》1978,1(1):46-53
The vegetation of a snow bed has been described by a pin-point method and a modified Raunkiær frequency analysis. The thawing of the snow has been followed and some soil properties have been investigated. It is concluded that the composition of the vegetation in the snow bed is influenced mainly by the duration of the growth period, but locally the density and the species composition are determined by the downward flow of the melt water. 相似文献
18.
Large single crystals of isocitrate dehydrogenase from Azotobacter vinelandii have been grown by vapor diffusion from ammonium sulfate and phosphate solutions. The crystals are tetragonal, space group P42212 with cell dimensions , . There are two molecules of 80,000 molecular weight per asymmetric unit. Native data to 5.5 Å resolution have been collected on a diffractometer. A rotation function using data between 10 Å and 6 Å resolution indicates three possible orientations of the non-crystallographic 2-fold axis relating the two molecules. 相似文献
19.
Dialysis Continuous Process for Ammonium-Lactate Fermentation of Whey: Mathematical Model and Computer Simulation 总被引:3,自引:3,他引:0
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A mathematical model was developed to describe a dialysis process for the continuous fermentation of whey lactose to lactic acid, with neutralization to a constant pH by ammonia. In the process, whey of a relatively high concentration is fed into the fermentor circuit at a relatively low rate so that the residual concentration of lactose is low. The fermentor effluent contains ammonium lactate, bacterial cells, and residual whey solids and could be used as a nitrogen-enriched feedstuff for ruminant animals. Only water is fed into the dialysate circuit at a relatively high rate. The dialysate effluent contains purified ammonium lactate and could be converted to lactic acid and ammonium sulfate for industry. The fermentation was specifically modeled as a set of equations representing material balances and rate relationships in the two circuits. Dialysis continuous fermentations, in general, were modeled by combining these equations and by using dimensionless parameters. The generalized model was then solved for the steady state and used to simulate the specific fermentation on a digital computer. The results showed the effects of various material and operational and kinetic parameters on the process and predicted that it could be operated efficiently. 相似文献
20.
Interaction of invertase with polyelectrolytes 总被引:1,自引:0,他引:1
Dautzenberg H Kötz J Philipp B Rother G Schellenberger A Mansfeld J 《Biotechnology and bioengineering》1991,38(9):1012-1019
In connection with our work on polyelectrolyte complex formation with polyampholytes, the interaction between invertase and several linear polyelectorlytes has been investigated by means of turbidimetry, light scattering measurements, and determination of the enzyme activity. Polyelectrolyte complex formation of invertase was shown to occur with cationic polyelectrolytes only. The light-scattering data yield information on aggregation and desegregation processes in complex formation. As indicated by our results, only a part of the protein molecules is engaged in this Coulombic interaction, and this part shows a rather small enzyme activity only. Thus, a direct interaction between invertase and a cationic polyelectrolyte is no effective approach to enzyme binding, but a complete immobilization of invertase can be achieved via an "inclusion flocculation" with a symplex formed by interaction between an anionic and a cationic linear polyelectrolyte or via immobilization in symplex microcapsules. 相似文献