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131.
To elucidate the food-entrainable oscillatory mechanism of peripheral clock systems, we examined the effect of fasting on circadian expression of clock genes including Dec1 and Dec2 in mice. Withholding of food for 2 days had these effects: the expression level of Dec1 mRNA decreased in all tissues examined, although Per1 mRNA level markedly increased; Per2 expression was reduced in the liver and heart only 42-46 h after the start of fasting; and expression profiles of Dec2 and Bmal1 were altered only in the heart and in the liver, respectively, whereas Rev-erbalpha mRNA levels did not change significantly. Re-feeding after 36-h starvation erased, at least in part, the effect of fasting on Dec1, Dec2, Per1, Per2, and Bmal1 within several hours, and restriction feeding shifted the phase of expression profiles of all examined clock genes including Dec1 and Dec2. These findings indicate that short-term fasting and re-feeding modulate the circadian rhythms of clock genes to different extents in peripheral tissues, and suggest that the expression of Dec1, Per1, and some other clock genes was closely linked with the metabolic activity of these tissues.  相似文献   
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133.
Over the last century, human activity has caused significant changes to the activity patterns of many wildlife species. The wild boar is one species known to change its activity pattern with the intensity of human disturbance. We conducted camera trap surveys in two study sites, Shingo and Himuro, in Tochigi, central Japan. We investigated effects of two types of human disturbance on the activity pattern of a wild boar population: ‘direct’ disturbance related to hunting activity and ‘indirect’ disturbance related to daily human activity. In the hunting season, relative abundance indices (RAI) of wild boars significantly decreased, and the proportion of activity at night increased compared with the nonhunting season. RAI of wild boars at night decreased with increasing distance from the settlement, while RAI of wild boars during the day did not. Relative proportion of activity at night was higher in cameras at 0–200 m from the settlements, while no significant pattern was found in cameras far from settlements. Both direct and indirect effects of human activity had a significant effect on the activity pattern of wild boars. A decrease in human activity may result in the rapid expansion of wild boar populations, and re-evaluation of the human factor is important for more intelligent management of wild boar populations and to solve the human–wildlife conflict.  相似文献   
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Immunohistochemical localization (cellular localization) of endogenous D-aspartate in the marine brown alga Sargassum fusiforme was investigated by the use of a specific polyclonal antibody raised against D-aspartate. D-Aspartate immunoreactivity was evident in the medullary layer in the blade of the alga, and weak staining was found in the cortical layer, whereas epidermal cells were found to lack D-aspartate. Within the cells of the layers, immunoreactivity was confirmed only in the cytosol and not in the cell wall, chloroplast, or vacuole. These results suggest that D-aspartate is present in S. fusiforme cells, and excludes the possibility that it is derived from attached or symbiotic organisms such as marine bacteria. This is the first report describing the localization of free D-aspartate in plant cells.  相似文献   
136.
This data paper reports tree census data collected in a network of 34 forest sites in Japan. This is the largest forest data set freely available in Japan to date. The network is a part of the Monitoring Sites 1000 Project launched by the Ministry of the Environment, Japan. It covers subarctic to subtropical climate zones and the four major forest types in Japan. Forty-two permanent plots, usually 1?ha in size, were established in old-growth or secondary natural forests. Censuses of woody species ??15?cm girth at breast height were conducted every year or once during 2004 to 2009. The data provide species abundance, survivorship and stem girth growth of 52,534 individuals of 334 tree and liana species. The censuses adopted common census protocol, which provide good opportunities for meta-analyses and comparative studies among forests. The data have been used for ecological studies as well as for the biodiversity reports published by the Ministry of the Environment.  相似文献   
137.
The bacterial community composition and diversity in rock varnish of Turpan Basin were investigated by restriction fragment length polymorphism (RFLP) and clone library of the 16S rRNA gene. 114 positive clones were screened, which could be grouped into 28 phylotypes and then further divided into 23 different operational taxonomic units (OTUs). These were affiliated into 5 phyla (Acidobacteria, Proteobacteria, Chloroflexi, Firmicutes and Cyanobacteria). Clones from actinobacteria were the dominant, accounting for 67.5% of total clones in the library, followed by Proteobacteria (15.8%), Chloroflexi (13.2%), Firmicutes (2.6%) and Cyanobacteria (0.9%). Rubrobacter (accounts for 35%) in the phylum Actinobacteria was the dominant genus and contained many species which might be resistant to gamma radiation. A 70% of the library clone sequences showed less 97% similarity to 16S rRNA gene sequences of standard strains obtained by pure culture. Shannon–Wiener index value of this study is 2.52 and is lower than deep-sea sediments, soils, lakes and other environments. Results of this study showed that bacterial diversity in rock varnishes of Turpan Basin was low, but maybe exist a large number of new unknown taxons, especially species that could well adapted to drought and resist radiation.  相似文献   
138.
We previously reported a series of 8-methyl-2-aryl-5-alkylaminoquinolines as a novel class of corticotropin-releasing factor-1 (CRF1) receptor antagonists. A critical issue encountered for this series of compounds was low aqueous solubility at physiological pH (pH 7.4). To address this issue, derivatization at key sites (R2, R3, R5, R5′, and R8) was performed and the relationships between structure and solubility were examined. As a result, it was revealed that introduction of a methoxy substituent at the C8 position had a positive impact on the solubility of the derivatives. Consequently, through in vivo and in vitro biological studies, compound 21d was identified as a potent, orally active CRF1 receptor antagonist with improved physicochemical properties.  相似文献   
139.
Miyamoto  Tetsuya  Katane  Masumi  Saitoh  Yasuaki  Sekine  Masae  Homma  Hiroshi 《Amino acids》2020,52(3):487-497
Amino Acids - Bacteria produce various d-amino acids, including non-canonical d-amino acids, to adapt to environmental changes and overcome a variety of threats. These d-amino acids are largely...  相似文献   
140.
In a previous study we isolated the meta-cleavage enzyme gene, tesB, that encodes an enzyme that carries out a meta-cleavage reaction in the breakdown of testosterone by Comamonas testeroni TA441 (M. Horinouchi et al., Microbiology 147:3367-3375, 2001). Here we report the isolation of a gene, tesD, that encodes a hydrolase which acts on the product of the meta-cleavage reaction. We isolated tesD by using a Tn5 mutant of TA441 that showed limited growth on testosterone. TesD exhibited ca. 40% identity in amino acid sequence with BphDs, known hydrolases of biphenyl degradation in Pseudomonas spp. The TesD-disrupted mutant showed limited growth on testosterone, and the culture shows an intense yellow color. High-pressure liquid chromatography analysis of the culture of TesD-disrupted mutant incubated with testosterone detected five major intermediate compounds, one of which, showing yellow color under neutral conditions, was considered to be the product of the meta-cleavage reaction. The methylation product was analyzed and identified as methyl-4,5-9,10-diseco-3-methoxy-5,9,17-trioxoandrosta-1(10),2-dien-4-oate, indicating that the substrate of TesD in testosterone degradation is 4,5-9,10-diseco-3-hydroxy-5,9,17-trioxoandrosta-1(10),2-dien-4-oic acid. 4,5-9,10-Diseco-3-hydroxy-5,9,17-trioxoandrosta-1(10),2-dien-4-oic acid was transformed by Escherichia coli-expressed TesD. Downstream of tesD, we identified tesE, F, and G, which encode for enzymes that degrade one of the products of 4,5-9,10-diseco-3-hydroxy-5,9,17-trioxoandrosta-1(10),2-dien-4-oic acid converted by TesD.  相似文献   
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