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71.
Akifumi S. Tanabe Satoshi Nagai Kohsuke Hida Motoshige Yasuike Atushi Fujiwara Yoji Nakamura Yoshihito Takano Seiji Katakura 《Molecular ecology resources》2016,16(2):402-414
The nuclear 18S‐rRNA gene has been used as a metabarcoding marker in massively parallel sequencing (MPS)‐based environmental surveys for plankton biodiversity research. However, different hypervariable regions have been used in different studies, and their utility has been debated among researchers. In this study, detailed investigations into 18S‐rRNA were carried out; we investigated the effective number of sequences deposited in international nucleotide sequence databases (INSDs), the amplification bias, and the amplicon sequence variability among the three variable regions, V1–3, V4–5 and V7–9, using in silico polymerase chain reaction (PCR) amplification based on INSDs. We also examined the primer universality and the taxonomic identification power, using MPS‐based environmental surveys in the Sea of Okhotsk, to determine which region is more useful for MPS‐based monitoring. The primer universality was not significantly different among the three regions, but the number of sequences deposited in INSDs was markedly larger for the V4–5 region than for the other two regions. The sequence variability was significantly different, with the highest variability in the V1–3 region, followed by the V7–9 region, and the lowest variability in the V4–5 region. The results of the MPS‐based environmental surveys showed significantly higher identification power in the V1–3 and V7–9 regions than in the V4–5 region, but no significant difference was detected between the V1–3 and V7–9 regions. We therefore conclude that the V1–3 region will be the most suitable for future MPS‐based monitoring of natural eukaryote communities, as the number of sequences deposited in INSDs increases. 相似文献
72.
K Kino K Mizumoto J Watanabe H Tsunoo 《The journal of histochemistry and cytochemistry》1987,35(3):381-386
In order to clarify the catabolism sites of Hb-Hp and free Hb, the organ distributions of [125I]-Hb-Hp and [125I]-Hb were studied, and the cell types in each organ incorporating them were determined by immunohistochemical methods. After administration of [125I]-Hb-Hp in very small amounts to rats, 84.5% was incorporated into the liver, but the renal uptake was only 0.6%. [125I]-Hb was incorporated into the kidneys rather than into the liver when a fivefold greater amount of [125I]-Hb than the binding capacity of plasma Hp was administered. Parenchymal cells, but not Kupffer cells, in the liver were stained with anti-Hb or anti-Hp IgG after administration of Hb in an amount corresponding to the Hb binding capacity of Hp. The proximal tubule cells, but not the distal tubule cells, in the kidney were stained with anti-Hb IgG after administration of a fivefold greater amount of Hb than the binding capacity of Hp. On the basis of these results, we suggest that Hb-Hp was incorporated mainly into liver parenchymal cells and did not traverse glomeruli in the kidney. In contrast to Hb-Hp, free Hb could pass through the glomeruli easily and was incorporated into the proximal tubule cells. 相似文献
73.
Shigehiro Asano Hitoshi Ban Koichi Kino Katsuhisa Ioriya Masami Muraoka 《Bioorganic & medicinal chemistry》2009,17(13):4636-4646
Based on 1,4-diarylpiperidine-4-methylureas, a new class of ACAT inhibitors, we examined in the study the SAR of a series of compounds prepared by replacing the substituent at the three aromatic parts. Introduction of long alkoxy group onto the phenyl moiety at the B-part was effective in improving both the inhibitory activity for ACAT and the up-regulatory activity for LDL-R expression. Particularly, 3-hydroxypropoxy group (43) on the phenyl moiety of B-part led to improved solubility, while keeping both biological activities. Compound 43 inhibited ACAT activity with an IC50 value of 18 nM, which is superior to that of a known ACAT inhibitor, CI-1011. In addition, compound 43 revealed an LDL-R up-regulatory activity comparable to that of SMP-797. We therefore expect this compound to be a novel ACAT inhibitor. 相似文献
74.
Imai Y Kanao T Sawada T Kobayashi Y Moriwaki Y Ishida Y Takeda K Ichijo H Lu B Takahashi R 《PLoS genetics》2010,6(12):e1001229
PTEN-induced kinase 1 (PINK1), which is required for mitochondrial homeostasis, is a gene product responsible for early-onset Parkinson's disease (PD). Another early onset PD gene product, Parkin, has been suggested to function downstream of the PINK1 signalling pathway based on genetic studies in Drosophila. PINK1 is a serine/threonine kinase with a predicted mitochondrial target sequence and a probable transmembrane domain at the N-terminus, while Parkin is a RING-finger protein with ubiquitin-ligase (E3) activity. However, how PINK1 and Parkin regulate mitochondrial activity is largely unknown. To explore the molecular mechanism underlying the interaction between PINK1 and Parkin, we biochemically purified PINK1-binding proteins from human cultured cells and screened the genes encoding these binding proteins using Drosophila PINK1 (dPINK1) models to isolate a molecule(s) involved in the PINK1 pathology. Here we report that a PINK1-binding mitochondrial protein, PGAM5, modulates the PINK1 pathway. Loss of Drosophila PGAM5 (dPGAM5) can suppress the muscle degeneration, motor defects, and shorter lifespan that result from dPINK1 inactivation and that can be attributed to mitochondrial degeneration. However, dPGAM5 inactivation fails to modulate the phenotypes of parkin mutant flies. Conversely, ectopic expression of dPGAM5 exacerbated the dPINK1 and Drosophila parkin (dParkin) phenotypes. These results suggest that PGAM5 negatively regulates the PINK1 pathway related to maintenance of the mitochondria and, furthermore, that PGAM5 acts between PINK1 and Parkin, or functions independently of Parkin downstream of PINK1. 相似文献
75.
Ying Zhou Takeshi Minami Kohsuke Honda Takeshi Omasa Hisao Ohtake 《Applied microbiology and biotechnology》2010,87(2):647-655
Systematic screening of single-gene knockout collection of Escherichia coli BW25113 (the Keio collection) was performed to select mutants that could enhance the deethylation of 7-ethoxycoumarin catalyzed
by CYP154A1. After 96-well plate high-throughput screening followed by test tube assays, four mutants (ΔcpxA, ΔgcvR, ΔglnL, and an unknown-gene-deleted one (Δuk)) were able to increase the CYP154A1 activity by approximately 1.4–1.7 times compared with that of the control strain. When
new mutants were constructed by disrupting individually the cpxA, gcvR, glnL, and uk genes in E. coli BW25113, three of them (ΔcpxA, ΔgcvR, and ΔglnL) showed high levels of CYP154A1 activity. However, the uk-disruptant failed to enhance the CYP154A1 activity, suggesting that the high CYP154A1 activity of the Δuk mutant in the Keio collection was due to a spontaneous mutation in the chromosome. In-frame deletion mutants of ΔcpxA, ΔgcvR, and ΔglnL also exhibited high enzyme activity, and complementation of these mutations could decrease CYP154A1 activity. These results
indicated that the enhancement of the enzyme activity was not caused by polar effects on their neighbor genes. To our knowledge,
this is the first report on a genome-wide screening of the genes for deletion to improve the activity of a recombinant whole-cell
biocatalyst. 相似文献
76.
Naoyuki Tajima Shusei Sato Fumito Maruyama Ken Kurokawa Hiroyuki Ohta Satoshi Tabata Kohsuke Sekine Takashi Moriyama Naoki Sato 《Journal of plant research》2014,127(3):389-397
We determined the complete nucleotide sequence of the plastid genome of the unicellular marine red alga Porphyridium purpureum strain NIES 2140, belonging to the unsequenced class Porphyridiophyceae. The genome is a circular DNA composed of 217,694 bp with the GC content of 30.3 %. Twenty-nine of the 224 protein-coding genes contain one or multiple intron(s). A group I intron was found in the rpl28 gene, whereas the other introns were group II introns. The P. purpureum plastid genome has one non-coding RNA (ncRNA) gene, 29 tRNA genes and two nonidentical ribosomal RNA operons. One rRNA operon has a tRNAAla(UGC) gene between the rrs and the rrl genes, whereas another has a tRNAIle(GAU) gene. Phylogenetic analyses suggest that the plastids of Heterokontophyta, Cryptophyta and Haptophyta originated from the subphylum Rhodophytina. The order of the genes in the ribosomal protein cluster of the P. purpureum plastid genome differs from that of other Rhodophyta and Chromalveolata. These results suggest that a large-scale rearrangement occurred in the plastid genome of P. purpureum after its separation from other Rhodophyta. 相似文献
77.
Kirimura K Yoda M Shimizu H Sugano S Mizuno M Kino K Usami S 《Bioscience, biotechnology, and biochemistry》2000,64(10):2034-2039
In Aspergillus niger, a cyanide (CN)- and antimycin A-insensitive and salicylhydroxamic acid (SHAM)-sensitive respiratory pathway exists besides the cytochrome pathway and is catalyzed by the alternative oxidase (AOX). In this study, A. niger WU-2223L, a citric acid-producing strain, was cultivated in a medium containing 120 g/l of glucose, which is the concentration usually needed for citric acid production, and the effects of 2% (v/v) methanol, an inducer of citric acid, 2 microM antimycin A, and 1 mM SHAM on AOX activities and citric acid production were investigated. The AOX activity, measured as duroquinol oxidase, was localized in the purified mitochondria regardless of the presence of any additives. When WU-2223L was cultivated with antimycin A or methanol, both citric acid production and citric acid productivity, shown as the ratio of production per mycelial dry weight, increased with the increase of both the activity of AOX and the rate of CN-insensitive and SHAM-sensitive respiration. On the other hand, when WU-2223L was cultivated with SHAM, an inhibitor of AOX, the CN-insensitive and SHAM-sensitive respiration was not detected and the citric acid production and the productivity drastically decreased, although mycelial growth was not affected. These results clearly indicated that the CN-insensitive and SHAM-sensitive respiration catalyzed by AOX, localized in the mitochondria, contributed to citric acid production by A. niger. 相似文献
78.
79.
Large‐scale culture of a megakaryocytic progenitor cell line with a single‐use bioreactor system 下载免费PDF全文
Retno Wahyu Nurhayati Yoshihiro Ojima Takeaki Dohda Masahiro Kino‐Oka 《Biotechnology progress》2018,34(2):362-369
The increasing application of regenerative medicine has generated a growing demand for stem cells and their derivatives. Single‐use bioreactors offer an attractive platform for stem cell expansion owing to their scalability for large‐scale production and feasibility of meeting clinical‐grade standards. The current work evaluated the capacity of a single‐use bioreactor system (1 L working volume) for expanding Meg01 cells, a megakaryocytic (MK) progenitor cell line. Oxygen supply was provided by surface aeration to minimize foaming and orbital shaking was used to promote oxygen transfer. Oxygen transfer rates (kLa) of shaking speeds 50, 100, and 125 rpm were estimated to be 0.39, 1.12, and 10.45 h?1, respectively. Shaking speed was a critical factor for optimizing cell growth. At 50 rpm, Meg01 cells exhibited restricted growth due to insufficient mixing. A negative effect occurred when the shaking speed was increased to 125 rpm, likely caused by high hydrodynamic shear stress. The bioreactor culture achieved the highest growth profile when shaken at 100 rpm, achieving a total expansion rate up to 5.7‐fold with a total cell number of 1.2 ± 0.2 × 109 cells L?1. In addition, cells expanded using the bioreactor system could maintain their potency to differentiate following the MK lineage, as analyzed from specific surface protein and morphological similarity with the cells grown in the conventional culturing system. Our study reports the impact of operational variables such as shaking speed for growth profile and MK differentiation potential of a progenitor cell line in a single‐use bioreactor. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 34:362–369, 2018 相似文献
80.
Various heterocyclic sulfur compounds such as naphtho[2,1-b]thiophene (NTH) and benzo[b]thiophene (BTH) derivatives can be detected in diesel oil, in addition to dibenzothiophene (DBT) derivatives. Mycobacterium phlei WU-0103 was newly isolated as a bacterial strain capable of growing in a medium with NTH as the sulfur source at 50°C. M. phlei WU-0103 could degrade various heterocyclic sulfur compounds, not only NTH and its derivatives but also DBT, BTH, and their derivatives at 45°C. When M. phlei WU-0103 was cultivated with the heterocyclic sulfur compounds such as NTH, NTH 3,3-dioxide, DBT, BTH, and 4,6-dialkylDBTs as sulfur sources, monohydroxy compounds and sulfone compounds corresponding to starting heterocyclic sulfur compounds were detected by gas chromatography–mass spectrometry analysis, suggesting the sulfur-specific desulfurization pathways for heterocyclic sulfur compounds. Moreover, total sulfur content in 12-fold-diluted crude straight-run light gas oil fraction was reduced from 1000 to 475 ppm S, with 52% reduction, by the biodesulfurization treatment at 45°C with growing cells of M. phlei WU-0103. Gas chromatography analysis with a flame photometric detector revealed that most of the resolvable peaks, such as those corresponding to alkylated derivatives of NTH, DBT, and BTH, disappeared after the biodesulfurization treatment. These results indicated that M. phlei WU-0103 may have a good potential as a biocatalyst for practical biodesulfurization of diesel oil. 相似文献