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213.
Galal Elgemeie Nahed Fathy Wafaa Zaghary Ayman Farag 《Nucleosides, nucleotides & nucleic acids》2017,36(3):198-212
A one-pot reaction of a sodium 2-cyanoethylene-1-thiolate salt with 2,3,4,6-tetra-O-acetyl-α-D-gluco- and galactopyranosyl bromides affords a new class of cyanoethylene thioglycosides. The conversion to the corresponding 5-aminopyrazoles confirms the E-configuration of these cyanoethylene thioglycosides. 相似文献
214.
Anna Faragó Péter Hasznos Ferenc Antoni Tibor Romhányi 《Biochimica et Biophysica Acta (BBA)/General Subjects》1978,538(3):493-504
Low- and high-affinity binding sites for cyclic GMP were found to be associated with the cyclic AMP-dependent protein kinase (ATP: protein phosphotransferase, EC 2.7.1.37) from human tonsillar lymphocytes, but neither of them was identical with the cyclic AMP binding site.The enzyme activated by cyclic GMP phosphorylated the same site of calf thymus H2b histone as the cyclic AMP activated enzyme; however, more complex kinetics of activation were found with cyclic GMP.Two classes of cyclic GMP binding site were demonstrated by kinetic analysis of cyclic [3H]GMP binding in the enzyme preparations eluted by 0.1 M potassium phosphate (pH 7.0) from DEAE cellulose. The high-affinity cyclic GMP binding site (Kd about 44 · 10?8 M belonged to some complex form of the protein kinase, as evidenced by the mutual inhibition of cyclic AMP binding and high affinity cyclic GMP binding. However, the high-affinity cyclic GMP binding site disappeared on Sephadex G-100 gel chromatography of the enzyme preparation, whereas the cyclic AMP binding activity was recovered quantitively as separate fractions. The low-affinity cyclic GMP binding site (Kd 2–5 · 10?6 M) was demonstrated by the inhibitory effect of 10?5 M cyclic GMP on cyclic AMP binding in each cyclic AMP binding fraction obtained by gel chromatography. However, cyclic AMP did not inhibit the binding of cyclic GMP to the low-affinity binding site. 相似文献
215.
The aim of this study was to evaluate the effect of transgenic alfalfa (Medicago sativa L.) plants, in comparison to their non-transgenic counterpart, on the density and physiological profiles of aerobic bacteria
in the rhizosphere. Plants of transgenic alfalfa expressing the AMVcp-s gene coding for Alfalfa Mosaic Virus coat protein were cultivated in a climatic chamber. Two methods were used to determine
the microbial diversity in rhizospheres of transgenic plants. First, the cultivation-dependent plating method, based on the
determination of the density of colony-forming bacteria, and second, a biochemical method using the Biolog™ system, based
on the utilization of different carbon sources by soil microorganisms. Statistically significant differences in densities
of rhizospheric bacteria between transgenic and non-transgenic alfalfa clones were observed in ammonifying bacteria (GTL4/404-1),
cellulolytic bacteria (GTL4/404-1, GTL4/402-2, A5-3-3), rhizobial bacteria (GTL4/402-2), denitrifying bacteria (A5-3-3) and
Azotobacter spp. (GTL4/402-2). The highest values of substrate utilization by microbial communities and average respiration of C-sources
were determined in non-transgenic alfalfa plants of the isogenic line SE/22-GT2. Carbohydrates, carboxylic acids and amino-acids
were the most utilized carbon substrates by both Gram-negative and Gram-positive bacteria. Both, the community metabolic diversity
and the utilization of C-sources increased in all alfalfa lines with culture time and regardless of transgenic or non-transgenic
nature of lines. 相似文献
216.
Comparison of six different populations of Xanthium strumarium grown under controlled laboratory conditions revealed a general pattern of greater chlorophyll levels with increase in latitude of origin. Indications of ultrastructural differences were found, with plants containing greater chlorophyll levels having more chloroplasts with greater membrane development compared to plants of this species from more southern or lower latitude habitats. 相似文献