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11.
Y Nagai K Akiyama S Kotani Y Watanabe T Shimono T Shiba S Kusumoto 《Cellular immunology》1978,35(1):168-172
The peptide N-acetylmuramyl-l-alanyl-d-isoglutamine (MDP), which has adjuvant activities, and 17 of its derivatives and analogs were synthesized and assayed to elucidate the structure necessary for adjuvant activity in induction of experimental allergic encephalomyelitis (EAE) in guinea pigs. The results revealed the importance of the d configuration and the α-carboxamide group of the isoglutaminyl residue of MDP for adjuvant activity. Replacement of the l-alanyl residue of MDP by d-alanine, but not by l-serine or glycine, resulted in a marked decrease in the activity. The β-methyl glycoside of MDP was found to be more active than the α-methyl derivative. 6-O-Stearoyl-N-acetylmuramyl-l-alanyl-d-isoglutamme showed activity. 相似文献
12.
Ayako Ueki Yukiko Fukushima Tetsuo Kimoto 《Virchows Archiv. B, Cell pathology including molecular pathology》1976,22(1):315-321
The presence of C3 receptor sites on the cell surfaces of WI-38 fibroblasts was reported in a previous paper. Here the effect of dexamethasone
sodium sulfate of C3 receptor site function was studied. The incubation of WI-38 fibroblasts with dexamethasone sodium sulfate produces the biphasic
mode of action, i.e., the growth-stimulating phase with low doses (90–230 μg/ml) and the growth-inhibiting phase with high
doses (450–900 μg/ml). The function of C3 receptor sites on WI-38 fibroblasts seems to be very stable and cannot be suppressed by the pretreatment of WI-38 fibroblasts
with dexamethasone in high concentrations, where the cell growth is inhibited. 相似文献
13.
Attempts were made to isolate and identify the unit chemical structure essential for manifestation of the immunoadjuvant activities characteristic of bacterial cell walls. The N-acetylmuramyl-peptide subunit monomers, Nalpha-(N-acetylmuramyl-L-alanyl-D-isoglutaminyl)-Nepsilon-(glycylglycyl)-L-lysyl-D-alanine from the cell walls of Staphylococcus aureus (FDA 209P) and N-acetylmuramyl-L-alanyl-D-isoglutaminyl-meso-diaminopimelic acid and/or N-acetylmuramyl-L-alanyl-D-isoglutaminyl-meso-diaminopimelyl-D-alanine from those of Lactobacillus plantarum (ATCC 8014), were shown to be unit chemical entities with definite adjuvant activity both in stimulation of antibody production and in induction of delayed-type hypersensitivity to ovalbumin when administered to guinea-pigs as water-in-oil emulsions. 相似文献
14.
Sakamoto K Hayashi A Sakamoto A Kiga D Nakayama H Soma A Kobayashi T Kitabatake M Takio K Saito K Shirouzu M Hirao I Yokoyama S 《Nucleic acids research》2002,30(21):4692-4699
A suppressor tRNA(Tyr) and mutant tyrosyl-tRNA synthetase (TyrRS) pair was developed to incorporate 3-iodo-L-tyrosine into proteins in mammalian cells. First, the Escherichia coli suppressor tRNA(Tyr) gene was mutated, at three positions in the D arm, to generate the internal promoter for expression. However, this tRNA, together with the cognate TyrRS, failed to exhibit suppressor activity in mammalian cells. Then, we found that amber suppression can occur with the heterologous pair of E.coli TyrRS and Bacillus stearothermophilus suppressor tRNA(Tyr), which naturally contains the promoter sequence. Furthermore, the efficiency of this suppression was significantly improved when the suppressor tRNA was expressed from a gene cluster, in which the tRNA gene was tandemly repeated nine times in the same direction. For incorporation of 3-iodo-L-tyrosine, its specific E.coli TyrRS variant, TyrRS(V37C195), which we recently created, was expressed in mammalian cells, together with the B.stearothermophilus suppressor tRNA(Tyr), while 3-iodo-L-tyrosine was supplied in the growth medium. 3-Iodo-L-tyrosine was thus incorporated into the proteins at amber positions, with an occupancy of >95%. Finally, we demonstrated conditional 3-iodo-L-tyrosine incorporation, regulated by inducible expression of the TyrRS(V37C195) gene from a tetracycline-regulated promoter. 相似文献
15.
Nagase Takahiro; Seki Naohiko; Tanaka Ayako; Ishikawa Ken-ichi; Nomura Nobuo 《DNA research》1995,2(4):167-174
In this series of projects regarding the accumulation of sequenceinformation of unidentified human genes, we newly deduced thesequences of 40 full-length cDNA clones of human cell line KG-1,and predicted the coding sequences of the corresponding genes,named KIAA0121 to 0160. The results of a computer search ofpublic databases indicated that the sequences of 13 genes wereunrelated to any reported genes, while the remaining 27 genescarried sequences which showed some similarities to known genes.Obvious unique sequences noted were as follows. A stretch oftriplet repeats was contained in each of three genes: Thesewere GAG(Glu) in KIAA0122 and KIAA0147, and TCC(Ser) in KIAA0150.A stretch of 10 amino acidresidues was repeated 21 times inKIAA0139, and a homologous sequence of 7678 nucleotideswas found repeated 6 times in the untranslated region of KIAA0125.northern hybridization analysis demonstrated that 13 genes wereexpressed in a cell- or tissue-specific manner. Although a vastnumber of expressed sequence tags (ESTs) have been registeredfor comprehensive analysis of cDNA clones, our sequence dataindicated that their distribution is very unbalanced: e.g. whileno EST hit 7 genes, 85 ESTs fell in a single gene. 相似文献
16.
Kosuke Yanagida Ayako Sakuda Chiho Suzuki-Minakuchi Masaki Shintani Kazuhiro Matsui Kazunori Okada 《Bioscience, biotechnology, and biochemistry》2016,80(5):1020-1023
The transferability of plasmids pCAR1, pB10, R388, and NAH7 was compared using the same donor-recipient system at different cell density combinations in liquid or on a solid surface. pCAR1 was efficiently transferred in liquid, whereas the other plasmids were preferentially transferred on a solid surface. Difference of liquid or solid affected the transfer frequency especially at lower cell densities. 相似文献
17.
Kazutoshi Shindo Ayako Osawa Yuki Kasai Nobuko Iba Ayako Saotome Norihiko Misawa 《Journal of Molecular Catalysis .B, Enzymatic》2007,48(3-4):77-83
Bioconversion experiments of various mono- or di-substituted naphthalenes such as dimethylnaphthalenes were carried out using the cells of Escherichia coli that expressed aromatic dihydroxylating dioxygenase genes (phnA1A2A3A4 and phdABCD) from polycyclic aromatic hydrocarbon-utilizing marine bacteria, Nocardioides sp. KP7 and Cycloclasticus sp. A5, respectively. We found that the former dioxygenase PhnA1A2A3A4 had broad substrate preference for these compounds and often was able to hydroxylate their methyl groups. Specifically, 1,4-dimethylnaphthalene was predominantly bioconverted into 1,4-dihydroxymethylnaphthalene. 相似文献
18.
Kondo-Okamoto N Noda NN Suzuki SW Nakatogawa H Takahashi I Matsunami M Hashimoto A Inagaki F Ohsumi Y Okamoto K 《The Journal of biological chemistry》2012,287(13):10631-10638
Autophagy-related degradation selective for mitochondria (mitophagy) is an evolutionarily conserved process that is thought to be critical for mitochondrial quality and quantity control. In budding yeast, autophagy-related protein 32 (Atg32) is inserted into the outer membrane of mitochondria with its N- and C-terminal domains exposed to the cytosol and mitochondrial intermembrane space, respectively, and plays an essential role in mitophagy. Atg32 interacts with Atg8, a ubiquitin-like protein localized to the autophagosome, and Atg11, a scaffold protein required for selective autophagy-related pathways, although the significance of these interactions remains elusive. In addition, whether Atg32 is the sole protein necessary and sufficient for initiation of autophagosome formation has not been addressed. Here we show that the Atg32 IMS domain is dispensable for mitophagy. Notably, when anchored to peroxisomes, the Atg32 cytosol domain promoted autophagy-dependent peroxisome degradation, suggesting that Atg32 contains a module compatible for other organelle autophagy. X-ray crystallography reveals that the Atg32 Atg8 family-interacting motif peptide binds Atg8 in a conserved manner. Mutations in this binding interface impair association of Atg32 with the free form of Atg8 and mitophagy. Moreover, Atg32 variants, which do not stably interact with Atg11, are strongly defective in mitochondrial degradation. Finally, we demonstrate that Atg32 forms a complex with Atg8 and Atg11 prior to and independent of isolation membrane generation and subsequent autophagosome formation. Taken together, our data implicate Atg32 as a bipartite platform recruiting Atg8 and Atg11 to the mitochondrial surface and forming an initiator complex crucial for mitophagy. 相似文献
19.
20.
Nakamura A Nakajima N Goda H Shimada Y Hayashi K Nozaki H Asami T Yoshida S Fujioka S 《The Plant journal : for cell and molecular biology》2006,48(2):193-205
We examined whether auxin/indole-3-acetic acid (Aux/IAA) proteins, which are key players in auxin-signal transduction, are involved in brassinosteroid (BR) responses. iaa7/axr2-1 and iaa17/axr3-3 mutants showed aberrant BR sensitivity and aberrant BR-induced gene expression in an organ-dependent manner. Two auxin inhibitors were tested in terms of BR responses. Yokonolide B inhibited BR responses, whereas p-chlorophenoxyisobutyric acid did not inhibit BR responses. DNA microarray analysis revealed that 108 genes were up-regulated, while only eight genes were down-regulated in iaa7. Among the genes that were up- or down-regulated in axr2, 22% were brassinolide-inducible genes, 20% were auxin-inducible genes, and the majority were sensitive neither to BR nor to auxin. An inhibitor of BR biosynthesis, brassinazole, inhibited auxin induction of the DR5-GUS gene, which consists of a synthetic auxin-response element, a minimum promoter, and a beta-glucuronidase. These results suggest that Aux/IAA proteins function in auxin- and BR-signaling pathways, and that IAA proteins function as the signaling components modulating BR sensitivity in a manner dependent on organ type. 相似文献