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991.
Sachi Nabeshima Taku Chiba Yutaka Takei Shiro Watanabe Harumi Okuyama Kikuo Onozaki 《Glycoconjugate journal》1998,15(1):69-74
In the previous study, galactose with C9 spacer was chemically coupled to human recombinant (rh) IL-1 alpha in order to study the effect of glycosylation on its activities, and to develop IL-1 with less deleterious effects. In this study we examined a variety of IL-1 activities in vitro, including proliferative effect on T cells, antiproliferative effect on myeloid leukemic cells and melanoma cells, stimulatory effects on IL-6 synthesis by melanoma cells and PGE2 synthesis by fibroblast cells Galactose-introduced IL-1 alpha (Gal-IL-1 alpha) exhibited reduced activities from 10 to 10000 times compared with unmodified IL-1 alpha in all the activities performed in vitro. The competitive binding of 125I-IL-1 alpha to mouse T cells and pre-B cells with unlabeled IL-1 alpha s suggests a decrease in binding affinities of Gal-IL-1 alpha to both type I and type II IL-1 receptors. Therefore, reduced activities of Gal-IL-1 alpha are due, at least partially, to the decrease in their receptor binding affinities. 相似文献
992.
Evidence of an increased risk of hearing loss in heterozygous carriers in a Wolfram syndrome family 总被引:5,自引:0,他引:5
Tomoaki Ohata A. Koizumi Tsuyoshi Kayo Yutaka Shoji Arata Watanabe Katsumi Monoh Koichiro Higashi Seiki Ito Osamu Ogawa Yasuhiko Wada Goro Takada 《Human genetics》1998,103(4):470-474
Wolfram syndrome (MIM 222300) is characterized by juvenile-onset diabetes mellitus and optic atrophy. Previous linkage analyses
in the United States and UK families have indicated that the gene for Wolfram syndrome (WFS) is localized on the short arm
of chromosome 4. We herein confirm the linkage of the WFS locus to D4S3023 on 4p with a two-point LOD score of 3.42 in a large
Japanese family with Wolfram syndrome. Multipoint linkage analysis revealed the maximum LOD score of 4.82 between D4S3023
and D4S394. We also evaluated putative health risks in carriers by multiple logistic analysis with independent variables,
age, gender, and numbers of affected haplotypes and with dependent variables, such as hearing loss, diabetes mellitus, polyuria,
incontinence, psychological illness, and visual acuity. The results showed that the putative disease haplotype increased a
risk of hearing loss (odds ratio =35.68, 95% confidence interval =4.12–308.95) and diabetes mellitus (odds ratio =7.57, 95%
confidence interval =2.03–28.23) independently. This is the first report of an increased health risk of illness in carriers,
other than for psychiatric disease.
Received: 23 June 1998 / Accepted: 15 August 1998 相似文献
993.
Fujita Kimikazu Kato Toshiaki Yamauchi Masamitsu Ando Masato Honda Masao Nagata Yutaka 《Neurochemical research》1998,23(2):169-174
Using one-dimensional polyacrylamide gel electrophoresis, we analyzed protein fractions extracted from the spinal cords of patients with amyotrophic lateral sclerosis (ALS). Several protein bands with molecular weights of 35–55 kDa were stained with Coomassie brilliant blue much more intensely in the ALS than in the non-ALS spinal cord. Glial fibrillary acidic protein (GFAP) immunoreactivity showed a significant decrease of 50 and 45 kDa band and increase in fragmented 36 and 37 kDa bands, which represented GFAP fragments devoid of 59 and 40 residues from the N-terminal, respectively, as determined by protein sequence analysis. Immunohistochemical examination of ALS spinal cord transections demonstrated increased GFAP-stained astrocytes in the shrunken ventral horn with massive degeneration of motoneurons. These results will provide new insight into the possible role of astrocytes in the pathophysiology and/or pathogenesis of ALS. 相似文献
994.
Isolation and characterization of a rice homebox gene, OSH15 总被引:4,自引:0,他引:4
In many eukaryotic organisms including plants, homeobox genes are thought to be master regulators that establish the cellular or regional identities and specify the fundamental body plan. We isolated and characterized a cDNA designated OSH15 (Oryza sativa homeobox 15) that encodes a KNOTTED-type homeodomain protein. Transgenic tobacco plants overexpressing the OSH15 cDNA showed a dramatically altered morphological phenotype caused by disturbance of specific aspects of tobacco development, thereby indicating the involvement of OSH15 in plant development. We analyzed the in situ mRNA localization of OSH15 through the whole plant life cycle, comparing the expression pattern with that of another rice homeobox gene, OSH1. In early embryogenesis, both genes were expressed as the same pattern at a region where the shoot apical meristem would develop later. In late embryogenesis, the expression pattern of the two genes became different. Whereas the expression of OSH1 continued within the shoot apical meristem, OSH15 expression within the shoot apical meristem ceased but became observable in a ring shaped pattern at the boundaries of some embryonic organs. This pattern of expression was similar to that observed around vegetative or reproductive shoots, or the floral meristem in mature plants. RNA in situ localization data suggest that OSH15 may play roles in the shoot organization during early embryogenesis and thereafter, OSH15 may be involved in morphogenetic events around the shoot apical meristem. 相似文献
995.
Yutaka Kawakami Noritaka Mochioka Koichiro Morishita Toshihiro Tajima Hisaki Nakagawa Hidetoshi Toh Akinobu Nakazono 《Environmental Biology of Fishes》1998,52(1-3):299-303
The effects of temperature and salinity on the concentration ratios of strontium (Sr) to calcium (Ca) within the sagittal otoliths of elvers of the Japanese eel, Anguilla japonica, were studied by spot analysis using a wavelength dispersive X-ray electron microprobe. A total of 340 elvers were used: 100 elvers were reared for 15 days under various salinity conditions (freshwater, one-third seawater, two-thirds seawater and pure seawater at 22 °C; 240 elvers were reared for 58 days under various water temperature conditions (12, 17, 22, 27 °C) in either freshwater or pure seawater. Otolith Sr/Ca ratios were found to be positively correlated with water salinity. On the other hand, the Sr/Ca ratios were not found to be significantly different among the various temperature groups. The above results strongly suggest that the physiological mechanism of incorporation of Sr and Ca within the otolith of an eurythermal fish, Japanese eel, does not change within this range of temperatures (12–27 °C). 相似文献
996.
Determination of the freshwater mark in otoliths of Japanese eel elvers using microstructure and Sr/Ca ratios 总被引:1,自引:0,他引:1
Yutaka Kawakami Noritaka Mochioka Koichiro Morishita Hidetoshi Toh Akinobu Nakazono 《Environmental Biology of Fishes》1998,53(4):421-427
The microstructure, in particular checks within the otolith edge, of Anguilla japonica glass-eels and elvers and changes in otolith Sr/Ca ratios were examined to ascertain the environmental history of the eels, especially with regard to the time when glass-eels entered the river, and as a benchmark for count daily increments. The percentage of glass eels and elvers with checks and the mean number of checks within the otoliths of glass-eels caught at four localities, Tosa Bay off Tosa City, the mouth of the Gokase River, the mouth of the Saigo River and the dam of the Tsuri River were 0% (0), 15.0% (0.2), 51.6% (1.0) and 100.0% (4.2), respectively. The Sr/Ca ratios and Sr content peaked in the region where checks were formed and the values decreased rapidly towards the edge of the checks; on the other hand, these decreased gradually in the otolith when checks were not formed. These checks were estimated to be formed by stress when the glass-eels were affected by ambient fresh water within the river. The innermost check was called the freshwater mark in the present study and this mark may be useful as a benchmark in studying the growth history of the eel before and after entering freshwater. 相似文献
997.
Induction of Reactive Oxygen Species in Neurons by Haloperidol 总被引:7,自引:0,他引:7
Yutaka Sagara 《Journal of neurochemistry》1998,71(3):1002-1012
Abstract: Haloperidol (HP) is widely prescribed for schizophrenia and other affective disorders but has severe side effects such as tardive dyskinesia. Because oxidative stress has been implicated in the clinical side effects of HP, rat primary cortical neurons and the mouse hippocampal cell line HT-22 were used to characterize the generation of reactive oxygen species (ROS) and other cellular alterations caused by HP. Primary neurons and HT-22 cells are equally sensitive to HP with an IC50 of 35 µ M in the primary neurons and 45 µ M in HT-22. HP induces a sixfold increase in levels of ROS, which are generated from mitochondria but not from the metabolism of catecholamines by monoamine oxidases. Glutathione (GSH) is an important antioxidant for the protection of cells against HP toxicity because (1) the intracellular GSH decreases as the ROS production increases, (2) the exogenous addition of antioxidants, such as β-estradiol and vitamin E, lowers the level of ROS and protects diol and vitamin E, lowers the level of ROS and protects HT-22 cells from HP, and (3) treatments that result in the reduction of the intracellular GSH potentiate HP toxicity. The GSH decrease is followed by the increase in the intracellular level of Ca2+ , which immediately precedes cell death. Therefore, HP causes a sequence of cellular alterations that lead to cell death and the production of ROS is the integral part of this cascade. 相似文献
998.
Formation of Protoplasts from Cultured Tobacco Cells and Arabidopsis thaliana by the Action of Cellulosomes and Pectate Lyase from Clostridium cellulovorans
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Yutaka Tamaru Sadaharu Ui Koichiro Murashima Akihiko Kosugi Helen Chan Roy H. Doi Bo Liu 《Applied microbiology》2002,68(5):2614-2618
The crude culture supernatants from Clostridium cellulovorans were tested for their ability to convert plant cells to protoplasts. The supernatants readily released protoplasts from cultured tobacco cells and Arabidopsis thaliana. The crude culture supernatant from pectin-grown cells was more active than supernatants from glucose-, cellobiose-, xylan-, and locust bean gum-grown cells. After removal of cellulosomes, the crude culture supernatant lost its protoplast formation activity. The protoplast formation activity of the crude culture supernatant from C. cellulovorans was more effective than those of commercial enzymes based on protein content. 相似文献
999.
Mitsutoshi Kitao Thomas T. Lei Takayoshi Koike Hiroyuki Tobita Yutaka Maruyama 《Physiologia plantarum》2003,118(3):406-413
The influence of long‐term drought stress on photosynthesis of Japanese mountain birch (Betula ermanii Cham.) was examined using chlorophyll fluorescence and gas exchange measurements. Drought stress was imposed in potted plants by reducing irrigation frequency from daily (control) to twice‐weekly and once‐weekly. Thirty‐day‐old leaves, which had developed under fully stressed conditions, were used for the measurements. The decline in net CO2 assimilation rate (A) observed in situ in drought‐stressed plants resulted from a lower intercellular CO2 concentration (Ci) due to stomatal closure but the carboxylation efficiency was not affected as there was no difference in the initial slope of the A/Ci response after watering. Although there were no treatment differences in A at Ci below 270 μmol mol?1 (with ambient air at 360 μmol mol?1 CO2), higher electron transport rate (ETR), photochemical quenching (qP) and the efficiency of energy conversion of open PSII (Fv′/Fm′), and similar or even lower non‐photochemical quenching (NPQ) were observed at a given Ci in drought‐stressed plants (of both twice‐ and once‐weekly irrigation), suggesting a higher fraction of open PSII resulting from energy dissipation achieved through higher electron flow rather than through thermal dissipation in PSII antennae. The once‐weekly watered plants showed a lower ratio of gross carbon assimilation rate to ETR (A*/ETR), suggesting an enhanced alternative pathway of electron flow probably involving the Mehler‐peroxidase (MP) reaction as indicated by a higher ΦPSII at a given ΦCO2 under non‐photorespiratory conditions. On the other hand, plants of twice‐weekly watering exhibited almost the same A*/ETR and ΦPSII–ΦCO2 relationship as control plants, indicating no enhanced alternative pathways under mild drought stress. 相似文献
1000.