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991.
Hiromasa Miyaji Tatsunari Nishi Akiko Saito Shuichiro Maeda Kazunori Shimada Toshio Hirano 《Bioscience, biotechnology, and biochemistry》2013,77(4):1135-1142
A mature human interleukin 2 (hIl-2) and its derivatives that lacked the N-terminal portion were expressed in Escherichia coli under the control of the phage λ PL promoter. They accumulated in the form of insoluble inclusion bodies and accounted for about 30% of the total cellular protein. The mature hIl-2 and its derivatives were further purified and their in vitro biological activity was compared in an Il-2 microassay. The results suggested that the hIl-2 derivatives without the N- terminal three or five amino acids were as active as intact hIl-2 and that those without the N- terminal eight or nine amino acids were less active than the intact form. 相似文献
992.
A relatively guanine-specific endoribonuclease (RB-1) was isolated from rice bran. The pH optimum was 8.5 using yeast RNA as a substrate. The enzyme activity was inhibited by Cu2+, Zn2+, DTT and SDS, while EDTA, PCMB, IAA and heparin had no effect on the activity. The enzymic activity of RB-1 was inhibited by 3′-GMP as an end-product inhibitor. The enzyme protein was highly heat-stable. RB-1 did not hydrolyze native calf thymus DNA, heat-denatured DNA, poly A, poly U and poly C. Among synthetic substrates, only poly I was depolymerized. Only 2′,3′-cyclic GMP was identified in the hydrolysate of yeast RNA after 6hr hydrolysis. 相似文献
993.
Mariko Kato Takashi Aoyama Masayoshi Maeshima 《The Plant journal : for cell and molecular biology》2013,74(4):690-700
Plasma membrane‐associated Ca2+‐binding protein–2 (PCaP2) of Arabidopsis thaliana is a novel‐type protein that binds to the Ca2+/calmodulin complex and phosphatidylinositol phosphates (PtdInsPs) as well as free Ca2+. Although the PCaP2 gene is predominantly expressed in root hair cells, it remains unknown how PCaP2 functions in root hair cells via binding to ligands. From biochemical analyses using purified PCaP2 and its variants, we found that the N–terminal basic domain with 23 amino acids (N23) is necessary and sufficient for binding to PtdInsPs and the Ca2+/calmodulin complex, and that the residual domain of PCaP2 binds to free Ca2+. In mutant analysis, a pcap2 knockdown line displayed longer root hairs than the wild‐type. To examine the function of each domain in root hair cells, we over‐expressed PCaP2 and its variants using the root hair cell‐specific EXPANSIN A7 promoter. Transgenic lines over‐expressing PCaP2, PCaP2G2A (second glycine substituted by alanine) and ?23PCaP2 (lacking the N23 domain) exhibited abnormal branched and bulbous root hair cells, while over‐expression of the N23 domain suppressed root hair emergence and elongation. The N23 domain was necessary and sufficient for the plasma membrane localization of GFP‐tagged PCaP2. These results suggest that the N23 domain of PCaP2 negatively regulates root hair tip growth via processing Ca2+ and PtdInsP signals on the plasma membrane, while the residual domain is involved in the polarization of cell expansion. 相似文献
994.
Eiki Takahashi Noriyuki Hirano Takashi Nagahara Satoru Yoshikawa Shinobu Momen Hiroshi Yokokawa Ryoji Hayashi 《Bioorganic & medicinal chemistry letters》2013,23(11):3154-3156
We aimed to discover a novel type of transient receptor potential vanilloid 1 (TRPV1) antagonist because such antagonists are possible drug candidates for treating various disorders. We modified the structure of hit compound 7 (human TRPV1 IC50 = 411 nM) and converted its pyrrolidino group to a (hydroxyethyl)methylamino group, which substantially improved inhibitory activity (15d; human TRPV1 IC50 = 33 nM). In addition, 15d ameliorated bladder overactivity in rats in vivo. 相似文献
995.
Kazuhiko Nakatani Mariko Toda Hanping He 《Bioorganic & medicinal chemistry letters》2013,23(2):558-561
A dimeric form of N-methoxycarbonyl-2-amino-1,8-naphthyridine (MCND) connected at the C2 position with a three-atom linker was examined for the binding to mismatches in double stranded RNA. Despite the fully complementary hydrogen bonding groups to guanine, MCND did not bind to guanine–guanine mismatch but did to adenine–adenine mismatch. The base pairs flanking the mismatch had weak effect on the binding, with showing the strongest binding to the A–A mismatch in the CAG/CAG sequence. The A–A mismatch in the GAC/GAC sequence was a poor substrate for the MCND binding. A monomeric derivative of MCND and another derivative lacking a methylcarbamate group showed negligilble binding to the A–A mismatch and the sequence selectivity. These results are important clues for the better molecular design of RNA binding small molecules. 相似文献
996.
997.
Fanmiao Wang Kenji Yano Shiro Nagamatsu Mayuko Inari‐Ikeda Eriko Koketsu Ko Hirano Koichiro Aya Makoto Matsuoka 《The Plant journal : for cell and molecular biology》2020,103(1):266-278
The morphology of rice (Oryza sativa L.) panicles is an important determinant of grain yield, and elucidation of the genetic control of panicle structure is very important for fulfilling the demand for high yield in breeding programs. In a quantitative trait locus (QTL) study using 82 backcross inbred lines (BILs) derived from Koshihikari and Habataki, 68 QTLs for 25 panicle morphological traits were identified. Gene expression profiling from inflorescence meristems of BILs was obtained. A combination of phenotypic QTL (pQTL) and expression QTL (eQTL) analysis revealed co‐localization between pQTLs and eQTLs, consistent with significant correlations between phenotypic traits and gene expression levels. By combining pQTL and eQTL data, two genes were identified as controlling panicle structure: OsMADS18 modulates the average length of the primary rachis and OsFTL1 has pleiotropic effects on the total number of secondary rachides, number of grains per panicle, plant height and the length of flag leaves. Phenotypes were confirmed in RNA interference knocked‐down plants and overexpressor lines. The combination of pQTL and eQTL analysis could facilitate identification of genes involved in rice panicle formation. 相似文献
998.
Hirano N Muroi T Kihara Y Kobayashi R Takahashi H Haruki M 《Applied microbiology and biotechnology》2011,89(6):1877-1884
Phage integrases are enzymes that catalyze unidirectional site-specific recombination between the attachment sites of phage
and host bacteria, attP and attB, respectively. We recently developed an in vivo intra-molecular site-specific recombination system based on actinophage TG1
serine-type integrase that efficiently acts between attP and attB on a single plasmid DNA in heterologous Escherichia coli cells. Here, we developed an in vivo inter-molecular site-specific recombination system that efficiently acted between the
att site on exogenous non-replicative plasmid DNA and the corresponding att site on endogenous plasmid or genomic DNA in E. coli cells, and the recombination efficiencies increased by a factor of ~101–3 in cells expressing TG1 integrase over those without. Moreover, integration of attB-containing incoming plasmid DNA into attP-inserted E. coli genome was more efficient than that of the reverse substrate configuration. Together with our previous result that purified
TG1 integrase functions efficiently without auxiliary host factors in vitro, these in vivo results indicate that TG1 integrase
may be able to introduce attB-containing circular DNAs efficiently into attP-inserted genomes of many bacterial species in a site-specific and unidirectional manner. This system thus may be beneficial
to genome engineering for a wide variety of bacterial species. 相似文献
999.
Minami M Ichikawa M Matsui H Hata N Wakiyama N Matsumoto M Ohta M Hasegawa T 《Current microbiology》2011,62(3):884-887
Streptococcus dysgalactiae subsp. equisimilis isolates (n = 110) were analyzed by PCR to determine whether the gene encoding SICG, a homolog of Streptococcus pyogenes SIC, was present. Nineteen strains (17%) had this gene of which 11 (55%) were isolated from patients with invasive disease. All 19 strains possessed group G carbohydrate. Molecular characterization of emm type revealed that the majority of emm sequences were stG643 and stG2078. Only the N-terminal sequence of SICG was similar to that of SIC in S. pyogenes. Although we found no significant relationship between pathogenic severity and sicG possession, further investigation into the mechanism of SICG may elucidate the virulence in S. dysgalactiae subsp. equisimilis infection. 相似文献
1000.
Yukitake H Naito M Sato K Shoji M Ohara N Yoshimura M Sakai E Nakayama K 《Microbiology and immunology》2011,55(3):141-153
The oral anaerobic bacterium Porphyromonas gingivalis, which is implicated as an important pathogen for chronic periodontitis, requires heme for its growth. Non-iron metalloporphyrins, In-PPIX and Ga-PPIX, were examined for antibacterial effects on P. gingivalis. Both In-PPIX and Ga-PPIX caused retardation of P. gingivalis growth in a dose-dependent fashion. Microarray and qPCR analyses revealed that In-PPIX treatment upregulated the expression of several genes encoding proteins including ClpB and ClpC, which are members of the Clp (caseinolytic protease, Hsp100) family, and aRNR, aRNR-activating protein and thioredoxin reductase, whereas In-PPIX treatment had no effect on the expression of genes encoding proteins involved in heme uptake pathways, Hmu-mediated, Iht-mediated and Tlr-mediated pathways. P. gingivalis ihtA and ihtB mutants were more resistant to In-PPIX than was the wild-type parent, whereas hmuR and tlr mutants did not show such resistance to In-PPIX. The results suggest that In-PPIX is incorporated by the Iht-mediated heme uptake pathway and that it influences protein quality control and nucleotide metabolism and retards growth of P. gingivalis. 相似文献