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431.
Takashi Akagi Ayako Ikegami Yasuhiko Suzuki Junya Yoshida Masahiko Yamada Akihiko Sato Keizo Yonemori 《Planta》2009,230(5):899-915
Persimmon fruits accumulate a large amount of proanthocyanidin (PA) during development. Fruits of pollination-constant and
non-astringent (PCNA) type mutants lose their ability to produce PA at an early stage of fruit development, while fruits of
the normal (non-PCNA) type remain rich in PA until fully ripened. To understand the molecular mechanism for this difference,
we isolated the genes involved in PA accumulation that are differentially expressed between PCNA and non-PCNA, and confirmed
their correlation with PA content and composition. The expression of structural genes of the shikimate and flavonoid biosynthetic
pathways and genes encoding transferases homologous to those involved in the accumulation of phenolic compounds were downregulated
coincidentally only in the PCNA type. Analysis of PA composition using the phloroglucinol method suggested that the amounts
of epigallocatechin and its 3-O-gallate form were remarkably low in the PCNA type. In the PCNA type, the genes encoding flavonoid 3′5′ hydroxylase (F3′5′H)
and anthocyanidin reductase (ANR) for epigallocatechin biosynthesis showed remarkable downregulation, despite the continuous
expression level of their competitive genes, flavonoid 3′ hydroxylation (F3′H) and leucoanthocyanidin reductase (LAR). We
also confirmed that the relative expression levels of F3′5′H to F3′H, and ANR to LAR, were considerably higher, and the PA composition corresponded to the seasonal expression balances in both types. These results
suggest that expressions of F3′5′H and ANR are important for PA accumulation in persimmon fruit. Lastly, we tested enzymatic activity of recombinant DkANR in vitro,
which is thought to be an important enzyme for PA accumulation in persimmon fruits. 相似文献
432.
Arata Kojima Takashi Umeda Kazuo Saito Yoshikazu Ookubo Junya Sato Shigeyuki Nakaji Masashi Matsuzaka Makoto Yaegaki Motoki Ohnishi Maki Miyazawa Ippei Takahashi 《Luminescence》2009,24(4):224-229
Sumo is a traditional Japanese sport, but the effect of actual daily training on neutrophil function is unknown. We evaluated the effect of sumo training on serum opsonic activity (SOA), which is one of the main neutrophil‐related functions. Seventeen male university sumo wrestlers participated in the study. Changes in anthropometric parameters, concentrations of serum immunoglobulins (IgG, IgA and IgM), complements (C3 and C4), myogenic enzymes (lactate dehydrogenase, asparate aminotransferase, alanine aminotransferase and creatine kinase), white blood cell/neutrophil counts and SOA were measured immediately before and after actual daily training for 2.5 h. Compared with the pre‐values, immunoglobulins and complements, myogenic enzymes and white blood cell/neutrophil counts significantly increased (p <0.01 for all). As for SOA, the values of the peak height and the area under the curve significantly increased after the training when assessed using lucigenin as a chemiluminigenic probe (p <0.01 for all), but showed no significant change when luminol was used as the chemiluminigenic probe. In conclusion, daily actual sumo training for 2.5 h increases SOA, thus possibly activating the reactive oxygen species production of neutrophils. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
433.
Tsuyoshi Watanabe Tohru Suzuki Akira Ishikawa Yuki Yokota Hiroki R. Ueda Rikuhiro G. Yamada Hajime Tei Saki Imai Shigeru Tomida Junya Kobayashi Emiko Naito Shinobu Yasuo Nobuhiro Nakao Takao Namikawa Takashi Yoshimura Shizufumi Ebihara 《PloS one》2009,4(1)
A new circadian variant was isolated by screening the intercross offspring of wild-caught mice (Mus musculus castaneus). This variant was characterized by an initial maintenance of damped oscillations and subsequent loss of rhythmicity after being transferred from light-dark (LD) cycles to constant darkness (DD). To map the genes responsible for the persistence of rhythmicity (circadian ratio) and the length of free-running period (τ), quantitative trait locus (QTL) analysis was performed using F2 mice obtained from an F1 cross between the circadian variant and C57BL/6J mice. As a result, a significant QTL with a main effect for circadian ratio (Arrhythmicity; Arrh-1) was mapped on Chromosome (Chr) 8. For τ, four significant QTLs, Short free-running period (Sfp-1) (Chr 1), Sfp-2 (Chr 6), Sfp-3 (Chr 8), Sfp-4 (Chr 11) were determined. An epistatic interaction was detected between Chr 3 (Arrh-2) and Chr 5 (Arrh-3). An in situ hybridization study of clock genes and mouse Period1::luciferase (mPer1::luc) real-time monitoring analysis in the suprachiasmatic nucleus (SCN) suggested that arrhythmicity in this variant might not be attributed to core circadian mechanisms in the SCN neurons. Our strategy using wild-derived variant mice may provide a novel opportunity to evaluate circadian and its related disorders in human that arise from the interaction between multiple variant genes. 相似文献
434.
Functional Analysis of an Arabidopsis thaliana Abiotic Stress-inducible Facilitated Diffusion Transporter for Monosaccharides 总被引:2,自引:0,他引:2
Kohji Yamada Yuriko Osakabe Junya Mizoi Kazuo Nakashima Yasunari Fujita Kazuo Shinozaki Kazuko Yamaguchi-Shinozaki 《The Journal of biological chemistry》2010,285(2):1138-1146
Sugars play indispensable roles in biological reactions and are distributed into various tissues or organelles via transporters in plants. Under abiotic stress conditions, plants accumulate sugars as a means to increase stress tolerance. Here, we report an abiotic stress-inducible transporter for monosaccharides from Arabidopsis thaliana that is termed ESL1 (ERD six-like 1). Expression of ESL1 was induced under drought and high salinity conditions and with exogenous application of abscisic acid. Promoter analyses using β-glucuronidase and green fluorescent protein reporters revealed that ESL1 is mainly expressed in pericycle and xylem parenchyma cells. The fluorescence of ESL1-green fluorescent protein-fused protein was detected at tonoplast in transgenic Arabidopsis plants and tobacco BY-2 cells. Furthermore, alanine-scanning mutagenesis revealed that an N-terminal LXXXLL motif in ESL1 was essential for its localization at the tonoplast. Transgenic BY-2 cells expressing mutated ESL1, which was localized at the plasma membrane, showed an uptake ability for monosaccharides. Moreover, the value of Km for glucose uptake activity of mutated ESL1 in the transgenic BY-2 cells was extraordinarily high, and the transport activity was independent from a proton gradient. These results indicate that ESL1 is a low affinity facilitated diffusion transporter. Finally, we detected that vacuolar invertase activity was increased under abiotic stress conditions, and the expression patterns of vacuolar invertase genes were similar to that of ESL1. Under abiotic stress conditions, ESL1 might function coordinately with the vacuolar invertase to regulate osmotic pressure by affecting the accumulation of sugar in plant cells. 相似文献
435.
436.
Tsujimoto T Kimura J Takeuchi Y Uyama H Park C Sung MH 《Journal of microbiology and biotechnology》2010,20(10):1436-1439
Many studies have clarified that poly(gamma-glutamic acid) (PGA) increases the solubility of Ca(2+), suggesting that PGA enhances calcium absorption in small intestine. However, there has been no report on the specific interaction between PGA and Ca(2+) in water. We studied the aqueous solution properties of PGA calcium salt (PGA-Ca complex). The chelating ability and binding strength of PGA for Ca(2+) were evaluated. PGA-Ca complex was soluble in water in contrast with the insolubility of poly(acrylic acid) (PAA) calcium salt and the chelating ability of PGA for Ca(2+) was almost the same than that of PAA. The globular conformation of PGA-Ca complex in water was estimated by SEC and viscosity measurements. The chelation of PGA for Ca(2+) was examined by 1H NMR. The present study showing the characteristics of PGA-Ca complex will provide useful information of the calcium absorption by PGA in vivo. 相似文献
437.
Development of a Genetic Transformation System for an Alga-Lysing Bacterium 总被引:15,自引:1,他引:14 下载免费PDF全文
Junichi Kato Junya Amie Yoshinori Murata Akio Kuroda Atsushi Mitsutani Hisao Ohtake 《Applied microbiology》1998,64(6):2061-2064
Four marine bacteria, Alteromonas sp. strains A27, A28, A29, and A30, that lyse the diatom Skeletonema costatum NIES-324 were isolated from coastal seawater samples. They were also able to lyse the diatoms Thalassiosira sp. and Eucampia zodiacs and the raphidophycean flagellate Chattonella antiqua. Cryptic indigenous plasmids, designated pAS28 and pAS29, were detected in Alteromonas sp. strains A28 and A29, respectively. These plasmids appeared to be similar based on size and restriction site analysis. A shuttle vector that replicates in Escherichia coli and Alteromonas sp. strain A28 was constructed by fusing pAS28 and E. coli vector pCRIIc. The 16-kbp chimeric plasmid, designated pASS1, had the ability to transform strain A28 at a frequency of 106 transformants per μg of DNA. Deletion analysis of pASS1 showed that the 4.7-kb EcoRI-HindIII region of pAS28 was essential for plasmid maintenance in strain A28. This EcoRI-HindIII fragment contained an open reading frame which appeared to encode a 708-amino-acid protein. 相似文献
438.
Satoshi Tahara John L. Ingham Shiro Nakahara Junya Mizutani Jeffrey B. Harborne 《Phytochemistry》1984,23(9):1889-1900
Chromatographic investigation of a methanolic extract of white lupin roots has revealed the presence of six new dihydrofuranoisoflavones (lupinisoflavones A-F). Three monoprenylated (3,3-dimethylallyl-substituted) isoflavones (wighteone, luteone and licoisoflavone A), two diprenylated isoflavones [6,3′-di(3,3-dimethylallyl)genistein (lupalbigenin) and 6,3′-di(3,3-dimethylallyl)-2′-hydroxygenistein (2′-hydroxylupalbigenin)] and two pyranoisoflavones (parvisoflavone B and licoisoflavone B) have also been isolated from the same source. In addition to genistein, leaf extracts of L. italbus contain 3′-O-methylorobol which is presumed to be the precursor of lupisoflavone [5,7,4′-trihydroxy-3′-methoxy-6-(3,3-dimethylallyl)isoflavone]. Probable biogenetic relationships between the prenylated, and dihydrofurano-and pyrano-substituted isoflavones in roots and leaves of L. albus are briefly discussed. 相似文献
439.
We present confirmation of the experimental penetration of Trichophyton mentagrophytes into human stratum corneum under designated
conditions of temperature and humidity. When stratum corneum, obtained from healthy human heel region, was incubated at 100%
humidity, mycelium was observed in the corneum layer on day 2 at 35 °C and 27 °C, and on day 4 at 15 °C. At 90% humidity,
the hyphae penetrated into the stratum corneum on day 4 at 35 °C, and on day 6 at 27 °C. Whereas, at 80% humidity, no fungal
elements were observed in the stratum corneum at both 27 °C and 35 °C for up to 7 day. These data suggested that humidity
was a more important environmental factor for penetration than temperature, and that at least 90% humidity is necessary for
dermatophytes to penetrate into the stratum corneum within a few days. Mean humidity in the interdigital space between the
fourth and fifth toes was found to be approximately 98%.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
440.
Aoyama T Okamoto T Kohno Y Fukiage K Otsuka S Furu M Ito K Jin Y Nagayama S Nakayama T Nakamura T Toguchida J 《Biochemical and biophysical research communications》2008,365(1):124-130
The expression of the chondromodulin-I (ChM-I) gene, a cartilage-specific gene, is regulated by the binding of Sp3 to the core promoter region, which is inhibited by the methylation of CpG in the target genome in the osteogenic lineage, osteosarcoma (OS) cells. The histone tails associated with the hypermethylated promoter region of the ChM-I gene were deacetylated by histone deacetylase 2 (HDAC2) in three ChM-I-negative OS cell lines. Treatment with an HDAC inhibitor induced the binding of Sp3 in one cell line, which became ChM-I-positive. This process was associated with acetylation instead of the dimethylation of histone H3 at lysine 9 (H3-K9) and, surprisingly, the demethylation of the core promoter region. The demethylation was transient, and gradually replaced by methylation after a rapid recovery of histone deacetylaion. These results represent an example of the plasticity of differentiation being regulated by the cell-specific plasticity of epigenetic regulation. 相似文献