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81.
82.
Sequence of cDNA encoding human insulin-like growth factor I precursor 总被引:10,自引:0,他引:10
M Jansen F M van Schaik A T Ricker B Bullock D E Woods K H Gabbay A L Nussbaum J S Sussenbach J L Van den Brande 《Nature》1983,306(5943):609-611
Somatomedins (SM) or insulin-like growth factors (IGF) constitute a heterogeneous group of peptides with important growth-promoting effects in vitro as well as in vivo. Amino acid sequences have been determined for only two of them, IGF-I and IGF-II, which are highly homologous. IGF-I, which is identical with SM-C, is composed of 70 amino acid residues and IGF-II contains 73 amino acids and may be identical with SM-A. Other peptides with different charge properties but with similar SM-like or insulin-like behaviour in biological and receptor assays, have been described but have not yet been fully characterized. The liver is known to be a major site of production of these peptides, but many other tissues--especially in the fetus--may synthesize them as well. We report here the nucleotide sequence of a human liver cDNA encoding the complete amino acid sequence of IGF-I. The IGF-I coding region is flanked by sequences encoding an amino-terminal peptide of at least 25 amino acid residues and a carboxyl-terminal peptide of 35 amino acids. This provides evidence that IGF-I is synthesized as a precursor protein and that formation of IGF-I from this precursor requires proteolytic processing at both ends. 相似文献
83.
M. Protiva M. Rajšner V. Trčka M. Vaněček Z. J. Vejdělek 《Cellular and molecular life sciences : CMLS》1959,15(2):54-55
Summary A series of cyclohexylamine derivatives methylated both on nitrogen atom and in position 1, 2 and 6 of the cyclohexane ring
have been prepared. Some of them showed considerable hypotensive and ganglioplegic activity. The most interesting compound
is N,N,1,2,2-pentamethylcyclohexylamine (‘penhexamine’) whose activity compares favourably with mecamylamine or dimecamine.
9. MitteilungGanglioplegica, 8. Mitteilung siehe Českoslov. farm:8 (1959), im Druck. 相似文献
9. MitteilungGanglioplegica, 8. Mitteilung siehe Českoslov. farm:8 (1959), im Druck. 相似文献
84.
85.
86.
Summary and conclusions The recent characterization of the human insulin receptor structure and its intrinsic tyrosine kinase activity represent major advances in our understanding of the mechanism of insulin action. It is reasonable to think that the insulin-induced autophosphorylation and activation of its receptor kinase represent an important event in the action of insulin on cell metabolism and growth. The fundamental research reviewed may be followed by the discovery of molecular receptor defects in clinical syndromes of insulin resistance. 相似文献
87.
S. J. Kleinschuster H. J. Rapp A. V. Johnston K. R. Van Kampen C. C. Muscoplat J. Bier 《Cellular and molecular life sciences : CMLS》1980,36(10):1239-1240
Summary A simple method for the anchorage-dependent culture of line 10 guinea-pig hepatoma cells is described. 相似文献
88.
Germline mosaicism and Duchenne muscular dystrophy mutations 总被引:12,自引:0,他引:12
E Bakker C Van Broeckhoven E J Bonten M J van de Vooren H Veenema W Van Hul G J Van Ommen A Vandenberghe P L Pearson 《Nature》1987,329(6139):554-556
Duchenne muscular dystrophy (DMD) is a severe X-linked neuromuscular disease with an incidence of approximately 1 in 3,500 newborn boys. The DMD locus has a high mutation frequency: one third of the cases is thought to result from a new mutation. Linkage studies using probes to detect restriction fragment length polymorphisms and DNA deletion studies have greatly improved DMD carrier detection and prenatal diagnosis. Here we report on two families in which a pERT87 (DXS164) deletion was transmitted to more than one offspring by women who showed no evidence for the mutation in their own somatic (white blood) cells. We also show that the deletion in both siblings in one of the families is identical, indicating that the deletion must have occurred during mitosis in early germline proliferation, leading to a germline mosaicism. This phenomenon may turn out to be a major factor contributing to the induction of DMD mutations, and has important implications for the counselling of DMD families. 相似文献
89.
N. H. Fraeyman E. J. Van de Velde F. H. De Smet 《Cellular and molecular life sciences : CMLS》1988,44(9):746-749
Summary Dopamine beta-hydroxylase (DBH) enzyme activity was associated in rat superior cervical ganglion with tetrameric DBH-A (294,000 D) and dimeric DBH-B (147,000 D) and in rat adrenal gland with DBH-A and a novel molecular form of DBH, defined as DBH-C, with a molecular weight of 125,000 D. Pretreatment of the rats with cycloheximide markedly reduced DBH activity without altering the molecular heterogeneity. 相似文献
90.
Deletion mapping of the inducible promoter of human IFN-beta gene 总被引:11,自引:0,他引:11