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991.
Junichi M. Imoto Kenji Saitoh Takeshi Sasaki Takahiro Yonezawa Jun Adachi Yuri P. Kartavtsev Masaki Miya Mutsumi Nishida Naoto Hanzawa 《Gene》2013
The distribution of freshwater taxa is a good biogeographic model to study pattern and process of vicariance and dispersal. The subfamily Leuciscinae (Cyprinidae, Teleostei) consists of many species distributed widely in Eurasia and North America. Leuciscinae have been divided into two phyletic groups, leuciscin and phoxinin. The phylogenetic relationships between major clades within the subfamily are poorly understood, largely because of the overwhelming diversity of the group. The origin of the Far Eastern phoxinin is an interesting question regarding the evolutionary history of Leuciscinae. Here we present phylogenetic analysis of 31 species of Leuciscinae and outgroups based on complete mitochondrial genome sequences to clarify the phylogenetic relationships and to infer the evolutionary history of the subfamily. 相似文献
992.
993.
994.
Yuri Nishimura Hiroki Shudo Hirokazu Seto Yu Hoshino Yoshiko Miura 《Bioorganic & medicinal chemistry letters》2013,23(23):6390-6395
The glycopolymers for glycosaminoglycan mimic were synthesized, and the inhibitory effects of Alzheimer’s β-secretase (BACE-1) were examined. The regio-selective sulfation was conducted on N-acetyl glucosamine (GlcNAc), and the acrylamide derivatives were synthesized with the consequent sulfated GlcNAc. The glycopolymers were synthesized with acrylamide using radical initiator. The glycopolymer with sulfated GlcNAc showed the strong inhibitory effect on BACE-1, and the inhibitory effects were dependent on the sulfation positions. Especially, glycopolymers carrying 3,4,6-O-sulfo-GlcNAc showed the strong inhibitory effect. The docking simulation suggested that glycopolymers bind to the active site of BACE-1. 相似文献
995.
Grigory Veinberg Maxim Vorona Liga Zvejniece Reinis Vilskersts Edijs Vavers Edvards Liepinsh Helena Kazoka Sergey Belyakov Anatoly Mishnev Jevgenijs Kuznecovs Sergejs Vikainis Natalja Orlova Anton Lebedev Yuri Ponomaryov Maija Dambrova 《Bioorganic & medicinal chemistry》2013,21(10):2764-2771
Novel positive allosteric modulators of sigma-1 receptor represented by 2-(5-methyl-4-phenyl-2-oxopyrrolidin-1-yl)-acetamide enantiomers were synthesised using an asymmetric Michael addition of 2-nitroprop-1-enylbenzene to diethyl malonate. Following the chromatographic separation of the methyl erythro- and threo-4-nitro-3R- and 3S-phenylpentanoate diastereoisomers, target compounds were obtained by their reductive cyclisation into 5-methyl-4-phenylpyrrolidin-2-one enantiomers and the attachment of the acetamide group to the heterocyclic nitrogen. Experiments with electrically stimulated rat vas deference contractions induced by the PRE-084, an agonist of sigma-1 receptor, showed that (4R,5S)- and (4R,5R)-2-(5-methyl-4-phenyl-2-oxopyrrolidin-1-yl)-acetamides with an R-configuration at the C-4 chiral centre in the 2-pyrrolidone ring were more effective positive allosteric modulators of sigma-1 receptor than were their optical antipodes. 相似文献
996.
Sho Konno Pillaiyar Thanigaimalai Takehito Yamamoto Kiyohiko Nakada Rie Kakiuchi Kentaro Takayama Yuri Yamazaki Fumika Yakushiji Kenichi Akaji Yoshiaki Kiso Yuko Kawasaki Shen-En Chen Ernesto Freire Yoshio Hayashi 《Bioorganic & medicinal chemistry》2013,21(2):412-424
We describe here the design, synthesis and biological evaluation of a series of molecules toward the development of novel peptidomimetic inhibitors of SARS-CoV 3CLpro. A docking study involving binding between the initial lead compound 1 and the SARS-CoV 3CLpro motivated the replacement of a thiazole with a benzothiazole unit as a warhead moiety at the P1′ site. This modification led to the identification of more potent derivatives, including 2i, 2k, 2m, 2o, and 2p, with IC50 or Ki values in the submicromolar to nanomolar range. In particular, compounds 2i and 2p exhibited the most potent inhibitory activities, with Ki values of 4.1 and 3.1 nM, respectively. The peptidomimetic compounds identified through this process are attractive leads for the development of potential therapeutic agents against SARS. The structural requirements of the peptidomimetics with potent inhibitory activities against SARS-CoV 3CLpro may be summarized as follows: (i) the presence of a benzothiazole warhead at the S1′-position; (ii) hydrogen bonding capabilities at the cyclic lactam of the S1-site; (iii) appropriate stereochemistry and hydrophobic moiety size at the S2-site and (iv) a unique folding conformation assumed by the phenoxyacetyl moiety at the S4-site. 相似文献
997.
Yoshihiro Noguchi Yuri Yasuda Makoto Tashiro Tadashi Kataoka Yoshiaki Kitamura Mahmoud Kandeel Yukio Kitade 《Parasitology international》2013,62(4):368-371
Plasmodium falciparum thymidylate kinase (PfTMK) is a promising antimalarial target due to its unique substrate specificity. Recently, we reported that 2′,3′-dideoxycarbocyclic thymidine showed moderate inhibitory activity and reported the related structure–activity relationship for inhibitors against PfTMK. In this study, we have designed and synthesized enantioselective 2′,3′-dideoxycarbocyclic pyrimidine nucleosides based on our previous results and screened them for inhibitory activity against PfTMK. The most potent inhibitor showed KiTMP and KidGMP values of 14 and 20 μM, respectively. The fluorinated dideoxy derivative (-)-7, exhibited lower KiTMP and higher KidGMP compared with that of the parent compound (KiTMP, KidGMP equals 20 and 7 μM, respectively). The modification of carbocyclic pyrimidine nucleosides is a promising strategy for developing powerful PfTMK inhibitors. 相似文献
998.
Fungal cell walls consist of various glucans and chitin. The inky cap, Coprinellus congregatus, produces mushrooms at 25°C in a regime of 15 h light/9 h dark, and then the mushroom is autolyzed rapidly to generate black liquid droplets in which no cell walls are detected by microscopy. Chitinase cDNA from the mature mushroom tissues of C. congregatus, which consisted of 1,622 nucleotides (chi2), was successfully cloned using the rapid amplification of cDNA ends polymerase chain reaction technique. The deduced 498 amino acid sequence of Chi2 had a conserved catalytic domain as in other fungal chitinase family 18 enzymes. The Chi2 enzyme was purified from the Pichia pastoris expression system, and its estimated molecular weight was 68 kDa. The optimum pH and temperature of Chi2 was pH 4.0 and 35°C, respectively when 4-nitrophenyl N,N′-diacetyl-β-D-chitobioside was used as the substrate. The K m value and V max for the substrate A, 4-nitrophenyl N,N′-diacetyl-β-D-chitobioside, was 0.175 mM and 0.16 OD min?1unit?1, respectively. 相似文献
999.
Anna V. Kutina Anna S. Marina Ivan I. Eliseev Mikhail I. Titov Yuri V. Natochin 《Journal of peptide science》2013,19(5):268-276
Vasopressin and nonmammalian hormone vasotocin are known to increase the water permeability of mammalian collecting ducts, frog skin and the urinary bladder. Neurohypophysial nonapeptides have also been shown to interfere with the regulation of renal ion transport. The subject of this study was a search for vasopressin and vasotocin analogues with selective effects on renal water, sodium and potassium excretion. During this study, we synthesised the following peptides: 13 vasotocin analogues modified at positions 4 (Thr or Arg), 7 (Gly or Leu) and 8 (d ‐Arg, Lys or Glu); 4 vasopressin analogues modified at positions 4 and 8; and 9 peptides shortened or extended at the C‐terminal or with substitutions for Gly‐NH2. Most of these peptides had mercaptopropionic acid (Mpa) instead of Cys in position 1. The effects of these nonapeptides on renal water, sodium and potassium transport were evaluated in in vivo experiments using Wistar rats. Some nonapeptides possessed antidiuretic, natriuretic and kaliuretic activities ([Mpa1]‐arginine vasotocin, [Mpa1, homoArg8]‐vasotocin, [Mpa1, Thr4]‐arginine vasotocin and [Mpa1, Arg4]‐arginine vasopressin). Substitutions at positions 4 and 8 increased the selectivity of peptide actions. The antidiuretic [d ‐Arg8]‐vasotocin analogues had no effects on sodium excretion. [Mpa1, Arg4]‐arginine vasotocin was antidiuretic and kaliuretic but not natriuretic. [Mpa1, Glu8]‐oxytocin had weak natriuretic activity without any effects on water and potassium transport. In accordance with the data obtained, synthesised vasotocin analogues could be good candidates for pharmaceuticals selectively regulating renal sodium and potassium transport, which is of clinical importance. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
1000.
Saito Y Shibayama H Tanaka H Tanimura A Matsumura I Kanakura Y 《Biochemical and biophysical research communications》2011,(2):41499-333
Anamorsin (AM) (also called CIAPIN-1) is a cell-death-defying factor. AM deficient mice die during late gestation; AM deficient embryos are anemic and very small compared to wild type (WT) embryos. It is thought that AM plays crucial roles in hematopoiesis and embryogenesis. To clarify the mechanisms of AM functions, we performed the yeast-two-hybrid assay to identify AM-interacting molecules; we found that PICOT (PKCθ interacting cousin of thioredoxin) preferentially bound to AM. We also showed that the N-terminal regions of both AM and PICOT were essential for their bindings and the inhibition of interaction of both molecules might lead to the cell growth retardation. Both PICOT and the yeast homolog of AM are known to be iron–sulfur proteins. The phenotype of PICOT deficient mice is very similar to that of anamorsin deficient mice; both mice are embryonic lethal. These data suggest that AM and PICOT might play cooperatively essential roles in embryogenesis as iron–sulfur cluster proteins. 相似文献