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111.
Hayashi N Chen R Ikezaki H Yamaguchi S Maruyama D Yamaguchi Y Ujihara T Kohata K 《Bioscience, biotechnology, and biochemistry》2006,70(3):626-631
A practical method for universal evaluation of the astringency of green tea infusion by a taste sensor system was established. The use of EGCg aqueous solution as a standard enabled analysis with high accuracy and reproducibility. The sensor output was converted into taste-intensity on the basis of Weber's and Weber-Fechner laws, which was named the "EIT(ast)" value ("EIT" and "ast" are abbreviations for "Estimated Intensity of Taste" and "astringency" respectively). It was clarified that green tea infusion is to be classified into eight grades on the EIT(ast) scale. Furthermore, the high correlation of the EIT(ast) value with the human gustatory sense and the high stability of the taste sensor were proved. 相似文献
112.
Takao Suzuki Minoru Moriya Toshihiro Sakamoto Takuya Suga Hiroyuki Kishino Hidekazu Takahashi Makoto Ishikawa Keita Nagai Yumiko Imai Etsuko Sekino Masahiko Ito Hisashi Iwaasa Akane Ishihara Shigeru Tokita Akio Kanatani Nagaaki Sato Takehiro Fukami 《Bioorganic & medicinal chemistry letters》2009,19(11):3072-3077
Optimization of high-throughput screening hit 1a led to the identification of a novel spiro-piperidine class of melanin-concentrating hormone 1 receptor (MCH-1R) antagonists. Compound 3c was identified as a highly potent and selective MCH-1R antagonist, which has an IC50 value of 0.09 nM at hMCH-1R. The synthesis and structure–activity relationships of the novel spiro-piperidine MCH-1R antagonists are described. 相似文献
113.
Masahiro Ono Shun Hayashi Hiroyuki Kimura Hidekazu Kawashima Morio Nakayama Hideo Saji 《Bioorganic & medicinal chemistry》2009,17(19):7002-7007
We synthesized push–pull benzothiazole derivatives and evaluated their potential as β-amyloid imaging probes. In binding experiments in vitro, the benzothiazoles showed excellent affinity for synthetic Aβ(1-42) aggregates. β-Amyloid plaques in the mouse and human brain were clearly visualized with the benzothiazoles, reflecting the results in vitro. These compounds may be a useful scaffold for the development of novel PET/SPECT and fluorescent tracers for detecting β-amyloid in Alzheimer’s brains. 相似文献
114.
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116.
Kana Sugimoto Hidekazu Tanaka Hiroshi Ochi Ryoji Matoba 《Biochemical and biophysical research communications》2009,390(4):1214-1807
Methamphetamine induces several cardiac dysfunctions, which leads to arrhythmia, cardiac failure and sudden cardiac death. Although these cardiac alterations elicited by methamphetamine were thought to be due to an indirect action of methamphetamine, namely, an excessive catecholamine release from synaptic terminals, while it seems likely that methamphetamine directly modulates the functioning of cardiomyocytes independent of neurotransmitters. However, the direct effects of methamphetamine on cardiomyocytes are still not clear. We show that methamphetamine directly accelerates the beating rate and alters Ca2+ oscillation pattern in cultured neonatal rat cardiomyocytes. Adrenergic receptor antagonists did not block the methamphetamine-induced alterations in cardiomyocytes. Treatment with a ryanodine receptor type 2 inhibitor and a sarcoplasmic reticulum Ca2+-ATPase inhibitor did not affect these responses, either. In contrast, the L-type Ca2+ channel inhibitor nifedipine eradicated these responses. Furthermore, methamphetamine elevated the internal free Ca2+ concentration in HEK-293T cells stably transfected with the L-type Ca2+ channel α1C subunit. In neonatal rat cardiomyocytes, methamphetamine accelerates beating rate and alters Ca2+ oscillation pattern by increasing Ca2+ entry via the L-type Ca2+ channels independent of any neurotransmitters. 相似文献
117.
Tanaka H Fujita K Sagisaka A Tomimoto K Imanishi S Yamakawa M 《Molecular biotechnology》2009,41(2):173-179
RNAi knockdown by using shRNA expression plasmids is widely used to determine the function of individual genes in mammals. Here we developed a simple method to create an IR DNA in a U6 small nuclear RNA promoter-based parent vector using a single-stranded IR DNA with short hairpin structure and Bst DNA polymerase. Furthermore, we demonstrated that the shRNA expression plasmids constructed by our method effectively induced target-specific RNAi in the silkworm cell line. We also found that sequence preference in the silkworm cell line was much lower than in mammalian cells and shRNA-induced RNAi was influenced by the length of the stem region. 相似文献
118.
Hidekazu Kobayashi Mikiko Yanaka Tatsuya M. Ikeda 《Journal of Plant Growth Regulation》2010,29(4):506-511
Jasmonates, including jasmonic acid and its derivatives such as methyl jasmonate (MeJA), are plant growth substances that
control various responses. Jasmonates regulate leaf trichome density in dicotyledonous plants, but their effects on the trichome
density of monocotyledonous plants, such as those in the Poaceae, remain unclear. In the present study we examined the effects
of exogenous MeJA on the trichome density of Rhodes grass, which has three kinds of trichomes: macrohairs, salt glands, and
prickles. Exogenous MeJA significantly increased the densities of macrohairs and salt glands on the adaxial and abaxial leaf
surfaces and those of prickles on the adaxial leaf surface. Because exogenous MeJA significantly reduced the leaf area, we
calculated the number of trichomes per 1000 epidermal cells to eliminate the effects of reduced leaf area. Exogenous MeJA
significantly increased the number of macrohairs per 1000 epidermal cells on both adaxial and abaxial leaf surfaces, but it
significantly decreased the number of salt glands per 1000 epidermal cells on both surfaces. Exogenous MeJA had no significant
effects on the number of prickles per 1000 epidermal cells on either of the leaf surfaces. These results indicate that exogenous
MeJA alters the trichome density by affecting leaf area and trichome initiation, and the effects of exogenous MeJA on trichome
initiation differ among the various trichome types. 相似文献
119.
Yoichi Kawazu Ryoi Fujiyama Yuji Noguchi Masaharu Kubota Hidekazu Ito Hiroyuki Fukuoka 《Transgenic research》2010,19(2):211-220
Lettuce big-vein disease is caused by Mirafiori lettuce virus (MiLV), which is vectored by the soil-borne fungus Olpidium brassicae. A MiLV-resistant transgenic lettuce line was developed through introducing inverted repeats of the MiLV coat protein (CP)
gene. Here, a detailed characterization study of this lettuce line was conducted by comparing it with the parental, non-transformed
‘Kaiser’ cultivar. There were no significant differences between transgenic and non-transgenic lettuce in terms of pollen
fertility, pollen dispersal, seed production, seed dispersal, dormancy, germination, growth of seedlings under low or high
temperature, chromatographic patterns of leaf extracts, or effects of lettuce on the growth of broccoli or soil microflora.
A significant difference in pollen size was noted, but the difference was small. The length of the cotyledons of the transgenic
lettuce was shorter than that of ‘Kaiser,’ but there were no differences in other morphological characteristics. Agrobacterium tumefaciens used for the production of transgenic lettuce was not detected in transgenic seeds. The transgenic T3, T4, and T5 generations showed higher resistance to MiLV and big-vein symptoms expression than the resistant ‘Pacific’ cultivar, indicating
that high resistance to lettuce big-vein disease is stably inherited. PCR analysis showed that segregation of the CP gene
was nearly 3:1 in the T1 and T2 generations, and that the transgenic T3 generation was homozygous for the CP gene. Segregation of the neomycin phosphotransferase II (npt II) gene was about 3:1 in the T1 generation, but the full length npt II gene was not detected in the T2 or T3 generation. The segregation pattern of the CP and npt II genes in the T1 generation showed the expected 9:3:3:1 ratio. These results suggest that the fragment including the CP gene and that including
the npt II gene have been integrated into two unlinked loci, and that the T1 plant selected in our study did not have the npt II gene. DNA sequences flanking T-DNA insertions in the T2 generation were determined using inverse PCR, and showed that the right side of the T-DNA including the npt II gene had been truncated in the transgenic lettuce. 相似文献
120.
Takata K Kitamura Y Saeki M Terada M Kagitani S Kitamura R Fujikawa Y Maelicke A Tomimoto H Taniguchi T Shimohama S 《The Journal of biological chemistry》2010,285(51):40180-40191
Reduction of brain amyloid-β (Aβ) has been proposed as a therapeutic target for Alzheimer disease (AD), and microglial Aβ phagocytosis is noted as an Aβ clearance system in brains. Galantamine is an acetylcholinesterase inhibitor approved for symptomatic treatment of AD. Galantamine also acts as an allosterically potentiating ligand (APL) for nicotinic acetylcholine receptors (nAChRs). APL-binding site is located close to but distinct from that for acetylcholine on nAChRs, and FK1 antibody specifically binds to the APL-binding site without interfering with the acetylcholine-binding site. We found that in human AD brain, microglia accumulated on Aβ deposits and expressed α7 nAChRs including the APL-binding site recognized with FK1 antibody. Treatment of rat microglia with galantamine significantly enhanced microglial Aβ phagocytosis, and acetylcholine competitive antagonists as well as FK1 antibody inhibited the enhancement. Thus, the galantamine-enhanced microglial Aβ phagocytosis required the combined actions of an acetylcholine competitive agonist and the APL for nAChRs. Indeed, depletion of choline, an acetylcholine-competitive α7 nAChR agonist, from the culture medium impeded the enhancement. Similarly, Ca(2+) depletion or inhibition of the calmodulin-dependent pathways for the actin reorganization abolished the enhancement. These results suggest that galantamine sensitizes microglial α7 nAChRs to choline and induces Ca(2+) influx into microglia. The Ca(2+)-induced intracellular signaling cascades may then stimulate Aβ phagocytosis through the actin reorganization. We further demonstrated that galantamine treatment facilitated Aβ clearance in brains of rodent AD models. In conclusion, we propose a further advantage of galantamine in clinical AD treatment and microglial nAChRs as a new therapeutic target. 相似文献