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101.
The factors controlling biomass production and the synthesis of astaxanthin esters in the microalga Haematococcus pluvialis (CCAP 34/7) have been investigated using a statistical approach employing response surface methodology (RSM). The culture
conditions required for optimal growth and carotenogenesis in this alga are very different. Of particular importance is the
photon flux density: for growth the optimum is 50–60 μmol m−2 s−1 whereas the optimum for astaxanthin synthesis is much higher at ∼-1600 μmol m−2 s−1. The addition of low levels of NaCl to the medium also stimulates to a small extent synthesis of astaxanthin, but photon
flux density remains the overriding factor. The optimal temperature for this strain is quite low at 14–15 °C. RSM has been
shown to be a rapid and effective technique leading to the optimisation of algal culture conditions. This statistical approach
can be applied readily to the majority of microalgae and their products. 相似文献
102.
Ke Gao Bo Xu Chaoshen Hong Xueliang Shi Hongbin Liu Xiaosong Li Linghai Xie Alex K‐Y Jen 《Liver Transplantation》2018,8(22)
Hole‐transporting materials (HTMs) are essential for enabling highly efficient perovskite solar cells (PVSCs) to extract and transport the hole carriers. Among numerous HTMs that are studied so far, the single‐spiro‐based compounds are the most frequently used HTMs for achieving highly efficient PVSCs. In fact, all the new spiro‐based HTMs reported so far that render PVSCs over 20% are based on spiro[fluorene‐9,9′‐xanthene] or spiro [cyclopenta [2,1‐b:3,4b′]dithiophene‐4,9′‐fluorene] cores; therefore, there is a need to diversify the design of their structures for further improving their function and performance. In addition, the fundamental understanding of structure–performance relationships for the spiro‐based HTMs is still lagging, for example, how molecular configuration, spiro numbers, and heteroatoms in spiro‐rings impact the efficacy of HTMs. To address these needs, two novel H‐shaped HTMs, G1 and G2 based on the di‐spiro‐rings as the cores are designed and synthesized. The combined good film‐forming properties, better interactions with perovskite, slightly deeper highest occupied molecular orbital, higher mobility and conductivity, as well as more efficient charge transfer for G2 help devices reach a very impressive power conversion efficiency of 20.2% and good stability. This is the first report of demonstrating the feasibility of using di‐spiro‐based HTMs for highly efficient PVSCs. 相似文献
103.
Olfaction plays an indispensable role in human and animals in self and environmental recognition, as well as intra‐ and interspecific communication. Following the discovery of a family of olfactory receptors (ORs) by Buck and Axel in 1991, it has been established that the sense of smell begins with the molecular recognition of a chemical odorant by one or more ORs expressed in the olfactory sensory neurons. Therefore, characterization of the molecular interactions between odorant molecules and ORs is a key step in the elucidation of the general properties of the olfactory system and in the development of applications, i.e., design of new odorants, search for blockers, etc. The process putted in place at ChemCom to improve the expression of ORs at the cytoplasmic membrane of the HEK293 cell and assays enabling large‐scale deorphanization, and to characterize the interaction between chemical odorants and ORs is described. The family of human ORs includes ca. 400 putatively functional ORs which are GPCRs (G protein‐coupled receptors); to date over 100 human ORs have been deorphanized. 相似文献
104.
The production of recombinant proteins in plants is an active area of research and many different high-value proteins have
now been produced in plants. Tobacco leaves have many advantages for recombinant protein production particularly since they
allow field production without seeds, flowers or pollen and therefore provide for contained production. Despite these biosafety
advantages recombinant protein accumulation in leaves still needs to be improved. Elastin-like polypeptides are repeats of
the amino acids “VPGXG” that undergo a temperature dependant phase transition and have utility in the purification of recombinant
proteins but can also enhance the accumulation of recombinant proteins they are fused to. We have used a 11.3 kDa elastin-like
polypeptide as a fusion partner for three different target proteins, human interleukin-10, murine interleukin-4 and the native
major ampullate spidroin protein 2 gene from the spider Nephila clavipes. In both transient analyses and stable transformants the concentrations of the fusion proteins were at least an order of
magnitude higher for all of the fusion proteins when compared to the target protein alone. Therefore, fusions with a small
ELP tag can be used to significantly enhance the accumulation of a range of different recombinant proteins in plant leaves.
An erratum to this article can be found at 相似文献
105.
106.
Alex Paton 《BMJ (Clinical research ed.)》1983,286(6370):1030-1031
107.
Summary The authors show that in certain isolated tissues (cornea of frog, mouse cancer) the mitotic processes continue during at least one hour. They are very strongly stimulated by heat and also by mitogenetic radiation. In the case of the cancer cells new mitoses are promoted in considerable number. A detailed analysis of both energy factors leads to the conclusion that they effect a disturbance of the unstable constellations (structures) of the elementary particles in the cell-body. Thus a certain degree of disorganisation of its plasma seems to stimulate cell-division. This statement is, in the opinion of the authors a proof that cell-division is controlled by a field, the trajectories of the elementary particles of the cell-body being a function of their coordinates relative to the cell-axes.
Résumé Les auteurs démontrent que dans certains tissus survivants (la cornée des yeux de grenouille et le cancer de souris) les mitoses continuent leur processus d'évolution durant au moins une heure. Par l'application de chaleur aussi bien que par l'irradiation mitogénétique on peut accélérer beaucoup le rhythme des mitoses en cours d'évolution et provoquer (dans les cas de cancer seulement) l'apparition d'un nombre considérable de nouvelles mitoses. L'analyse de l'action de ces deux facteurs d'énergie aboutit à la conclusion qu'il ne peut s'agir que d'un dérangement des constellations instables des éléments du corps cellulaire. On peut en déduire qu'un certain degré de désorganisation du plasme est favorable aux divisions cellulaires. En poursuivant et en développant cette conception, les auteurs arrivent à la conception du champ cellulaire de division, définissant les trajectoires des particules élémentaires comme fonction de ses coordonnés relativement aux axes des cellules.相似文献
108.
A trypsin and chymotrypsin inhibitor was partially purified from Bauhenia purpurea seeds and separated from a second inhibitor by Ecteola cellulose chromatography. The factor inhibited bovine trypsin and chymotrypsin as well as pronase trypsin and elastase. It formed a complex with trypsin and with chymotrypsin, but a ternary complex could not be detected. Differences were detected in the effect on trypsin and on chymotrypsin, although one enzyme interfered with the inhibition of the other. The results obtained point to two active centers on the inhibitor for the trypsin and chymotrypsin inhibition such that the one cannot complex with the inhibitor after this inhibitor had complexed with the other. 相似文献
110.