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91.
Summary Experiments were conducted to determine the influence of N, P, and K and of the NP and NK interactions on root yields and
tissue concentrations of N, P, and K of rutabagas grown on a sandy loam soil under greenhouse conditions. Root yields were
increased by applications of N and K but not by added P. The yield response to N was dependent on K supply. The highest dry
matter content in roots was associated with the lowest rates of N and K and the lowest root yields.
The N content of tissue at the early vegetative stage increased with increasing rates of N and decreased with increasing rates
of P and K. The N content of root tissue at harvest increased at the highest rates of N but was unaffected by rates of P and
K. The P and K content of root tissue increased with increasing rates of P and K, respectively.
The levels of nutrients in early vegetative tissue associated with optimum yields were about 2.6, 0.24, and 2.0% for N, P,
and K, respectively. The corresponding values in the leaf tissue at harvest were about 1.2, 0.12, and 1.5% N, P, and K, respectively.
Contribution No.222. 相似文献
92.
93.
D. Gupta I. Kovács 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1974,45(2):64-71
Summary Hybrids obtained from two series of diallel crosses made between six o
2 converted inbred lines on the one hand and their normal analogues on the other were compared for twenty-five characters including yield and several of the yield components, including the parents. Observations on simple inter-character correlation coefficients presented here have shown that the majority of the correlations at the o
2 level are of the same order as at the normal level. A number of correlations of the o
2 type are inferior to those of their normal analogues, whereas a few are favoured by the o
2 gene including the correlation of grain yield with kernels per row. A measure of heterosis for each hybrid over its mid-parent also demonstrated that the o
2 types show poorer heterosis in more cases than do their normal counterparts. Still, in nearly 40 percent of the cases the o
2 hybrids were found to be more heterotic than their normal analogues, particularly for the various maturity characters and several of the yield components. Thus, the possibility of improvement exists in breeding maize with the opaque-2 gene. 相似文献
94.
The 0.5M KCl wash of rabbit reticulocyte ribosomes (I fraction) catalyzes the deacylation of Met-tRNAfMet. Upon DEAE-cellulose column chromatography, the deacylase activity elutes with the 0.1M KCl wash of the column (f1) and is well-resolved from the peptide chain initiation factors (1–3). The deacylase activity is specific for Met-tRNAfMet (retic., ). Other aminoacyl tRNAs tested including fMet-tRNAfMet (retic., ), Phe-tRNA (), Val-tRNA (retic.), and Arg-tRNA (retic.) are completely resistant to the action of the deacylase. In the presence of the peptide chain initiation factor (IF1) and GTP, retic. Met-tRNAfMet forms the initiation complex Met-tRNAfMet:IF1:GTP (2), and in this ternary complex Met-tRNAfMet is not degraded by the deacylase. Met-tRNAfMet binds to IF1 independent of GTP, and in this complex, this Met-tRNAfMet is degraded by the deacylase.Prior incubation of f1 with Met-tRNAfMet (retic.) strongly inhibited protein synthesis initiation, presumably due to deacylation of the initiator tRNA. This inhibition by f1 was completely prevented when Met-tRNAfMet (retic.) was pre-incubated with peptide chain initiation factors. 相似文献
95.
S L Gupta M L Sopori P Lengyel 《Biochemical and biophysical research communications》1973,54(2):777-783
Protein synthesis directed by exogenous (viral or cellular) messengers is impaired, but endogenous protein synthesis is not affected in an extract of interferon-treated Ehrlich ascites tumor cells (INT-extract). Protein synthesis directed by exogenous messengers is also impaired in a mixture of an INT-extract with an extract from control cells. This reveals that the impairment is due to one or more inhibitors in the INT-extract. The nondialyzability of the inhibitor(s) is probably an indication of large molecular size. In a not incubated INT-extract much of the inhibitory activity is in the high speed sediment fraction i.e., is presumably bound directly or indirectly to ribosomes. During incubation of the extract most of the inhibitory activity is released into the high speed supernatant fraction. The dose-response curve shows that in our conditions the translation of cellular messengers (from mouse L cells) is as sensitive to impairment by the inhibitor(s) as that of viral messengers (from reovirus or from encephalomyocarditis virus). 相似文献
96.
Mass spectra of nucleoside components of tRNA 总被引:2,自引:0,他引:2
97.
98.
Nocardiosis: A review 总被引:2,自引:0,他引:2
99.
100.
Expression and posttranslational processing of preprodynorphin complementary DNA in the mouse anterior pituitary cell line AtT-20 总被引:2,自引:0,他引:2
A recombinant plasmid containing the rat prodynorphin cDNA was introduced into the mouse anterior pituitary corticotroph cell line AtT-20. These cells normally express and posttranslationally process proopiomelanocortin, but not prodynorphin. Stable transformants were isolated and analyzed for the expression and processing of prodynorphin. The stably transformed AtT-20 cells that expressed a 1.3-kilobase prodynorphin mRNA also expressed prodynorphin protein and processed it to dynorphin peptides. The peptides included leucine-enkephalin, beta-neoendorphin, dynorphin-A8, and dynorphin-B, as identified by gel filtration and reverse phase HPLC followed by RIA using peptide-specific antisera. These results demonstrate that AtT-20 cells efficiently and accurately process prodynorphin at both dibasic sites and monobasic cleavage sites, indicating that the AtT-20 cells contain enzymes capable of cleaving the precursor not only at dibasic residues but also at monobasic residues. The release of prodynorphin-derived peptides paralleled secretion of endogenous proopiomelanocortin-derived peptides when stimulated by CRF, a natural secretagogue for ACTH. 相似文献