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101.
Kambe-Honjoh H Ohsumi K Shimoi H Nakajima H Kitamoto K 《The Journal of General and Applied Microbiology》2000,46(3):113-117
A fusion protein of hexa-histidine repeat (His) and glycosylphosphatidylinositol (GPI)-anchor region of Saccharomyces cerevisiae Cwp1 with Aspergillus oryzae Taka-amylase A (TAA) was expressed on the yeast cell surface. The expressed fusion protein (TAA-His-Cwp1) was localized on the cell wall and demonstrated amylolytic activity. In comparison with the TAA-Cwp1 expressing strain, these cells exhibited 1.6- to 2.8-fold higher adsorbing capacity for Cu(2+), Ni(2+), and Zn(2+). 相似文献
102.
Transformation of Japanese persimmon (Diospyros kaki Thunb.) with a bacterial gene for choline oxidase 总被引:4,自引:0,他引:4
Gao Mei Sakamoto Atsushi Miura Keisuke Murata Norio Sugiura Akira Tao Ryutaro 《Molecular breeding : new strategies in plant improvement》2000,6(5):501-510
This report describes the first successful genetic engineering of tolerance to salt in an agriculturally important species of woody plants by Agrobacterium-mediated transformation with the codA gene of Arthrobacter globiformis. This gene encodes choline oxidase, which catalyzes the oxidation of choline to glycinebetaine. The binary plasmid vector pGC95.091, containing a kanamycin-resistance gene (nptII), a gene for -glucuronidase (gusA) and the codA gene in its T-DNA region, was used with a disarmed strain of Agrobacterium tumefaciens, EHA101, to transform Japanese persimmon (Diospyros kaki Thunb. `Jiro') by the leaf disk transformation method. The pRS95.101 plasmid that included only nptII and gusA in the T-DNA region was used as a control. We selected eight transgenic lines with one or two copies of the T-DNA after transformation with pGC95.091 (PC lines) and three lines after transformation with pRS95.101 (PR lines). The eight PC lines produced choline oxidase and glycinebetaine whereas neither was found in untransformed `Jiro' and in the control PR lines. Transgenic plants grew normally, resembling wild-type plants both in vitro and ex vitro. The activity of photosystem II in leaves of the transgenic Japanese persimmon plants under NaCl stress was determined in terms of the ratio of the variable (F
v) to the maximum (F
m) fluorescence of chlorophyll (F
v/F
m). The rate of decline in (F
v/F
m under NaCl stress was lower in the PC lines than in the control PR lines. These results demonstrated that genetic engineering of Japanese persimmon, which allowed it to accumulate glycinebetaine, enhanced the tolerance to salt stress of this plant. 相似文献
103.
Keisuke Uno Shinya Shimada Junji Tsuruta Housei Matsuzaki Satoshi Tashima Michio Ogawa 《The Histochemical journal》1998,30(8):553-559
Our previous reports have demonstrated frequent and strong expression of glycogen phosphorylase (EC 2.4.1.1) activity mainly in the cytoplasm of gastric carcinoma. Although previous studies have suggested the phosphorylase glyco-syltransferase system to be in the nucleus from enzyme histochemical analyses, intranuclear localization of the phosphorylase has not been fully established. The aims of the present study are to investigate the nuclear localization of glycogen phosphorylase and to identify the isoform of phosphorylase in the nucleus of gastrointestinal carcinoma. The activity of glycogen phosphorylase in carcinoma cells corresponding to the nucleus was demonstrated using enzyme cytochemical analysis. The phosphorylase activity coincided with localization revealed by immunocytochemistry using affinity-purified specific anti-human brain-type glycogen phosphorylase antibody. The isoform expressed in the nuclei of carcinoma cells was identified as bei ng only the brain type according to a polymerase chain reaction-based assay using RNA obtained from gastric carcinoma cells and primers specific to muscle, liver and brain types of glycogen phosphorylase. The intranuclear localization of the brain-type isoform was confirmed by immunoelectron microscopical analyses. Further investigation to examine the nuclear localization in human carcinoma tissue (145 and 25 specimens with gastric and colonic carcinoma respectively) was carried out by immunohistochemistry using specific anti-brain-type antibody. Nuclear immunostaining was observed in seven cases out of 145 gastric carcinoma. The present study is the first to clarify the nuclear localization of glycogen phosphorylase with enzymatic activity in gastrointestinal carcinoma. The isoform of the enzyme expressed in the carcinoma was identified as the brain type. These results warrant further studies on the mechanisms for transporting the large molecule of brain-type glycogen phosphorylase to nuclei and its function in the nucleus of carcinoma cells. 相似文献
104.
105.
Induction of 72-kDa Inducible Heat Shock Protein (HSP72) in Cultured Rat Astrocytes After Energy Depletion 总被引:2,自引:1,他引:1
Naohiko Imuta Satoshi Ogawa ‡Yusuke Maeda †Keisuke Kuwabara †Osamu Hori Hirokazu Ueda Takehiko Yanagihara Masaya Tohyama 《Journal of neurochemistry》1998,70(2):550-557
Abstract: Protein synthesis is important in the readaptive processes for cultured astrocytes after hypoxia and subsequent reoxygenation. We have identified 72-kDa inducible heat shock protein (HSP72) as a major stress protein in reoxygenated astrocytes. To assess the mechanism for reoxygenation-mediated induction of HSP72, a reporter gene that consists of a human HSP promoter fused to the luciferase gene was transfected into cultured astrocytes. Analysis of cellular energy nucleotides showed an increase of the ADP/ATP ratio after reoxygenation, which synchronized with activation of the HSP promoter. Activation of the HSP promoter was also observed after an addition of iodoacetic acid to hypoxic astrocytes, which reached the maximum when the ADP/ATP ratio reached 50%, but further decline in the energy profile caused inactivation of this promoter. Inhibition of protein synthesis after reoxygenation resulted in temporary restoration of the energy profile and suppression of the DNA binding activity of the heat shock factor. Addition of quercetin greatly decreased the [3 H]leucine incorporation in the polysome fraction without any effect on the mature mRNA formation. These data suggest that the energy depletion in reoxygenation triggers induction of HSP72 after reoxygenation, which may act as a pivotal mediator in the stress response of reoxygenated astrocytes by facilitating protein synthesis. 相似文献
106.
Hideko Kambe-Honjoh Shoji Hata Keisuke Ohsumi Katsuhiko Kitamoto 《Biotechnology Techniques》1998,12(2):91-95
A novel bioassay system for estimating concentrations of several heavy metal ions was carried out with yeast mutants which are highly sensitive to heavy metal ions. The method does not need an atomic adsorption spectrometer or other special equipment. It is suitable for screening of microorganisms that efficiently remove heavy metal ions from aqueous solution. 相似文献
107.
The presence of plasmids was surveyed in 90 wild isolates ofLentinula edodes collected from geographically different world regions. DNA plasmids of different sizes were found in about 80% of the isolates.
The plasmids detected were of six kinds, designated as pLE1 (9.0 kb), pLE2 (11.1 kb,=pLLE1 described by other authors), pLE3A
(9.8 kb), pLE3B (10.8 kb), pLE3C (12.1 kb), and pLE3D (12.3 kb). Hybridization analysis suggested that pLE1 and pLE2 were
distinct plasmid types of different homology groups to each other, and the four other plasmids were variant types belonging
to a third homology group. These plasmids had no homology with their host's and non-host's nuclear and mitochondrial genome
DNAs. Restriction analysis and electron microscopy indicated that the plasmids are linear in form. Since all six plasmids
were transmitted uniparentally in sexual crosses and were consistently associated with the DNA preparations from mitochondria
fractionated from mycelia of representative isolates, they were suggested to be located in mitochondria, similar to many other
known fungal DNA plasmids. Geographically, pLE1 and pLE2 were widely distributed in natural populations ofL. edodes, while the remaining four plasmids were uniquely present in delimited natural populations.
Contribution No. 322 from the Tottori Mycological Institute. 相似文献
108.
Wadano Akira Nishikawa Keisuke Hirahashi Tomohiro Satoh Ryohei Iwaki Toshio 《Photosynthesis research》1998,56(1):27-33
The dependence of the activity of phosphoribulokinase isolated from a cyanobacterium, Synechococcus PCC7942, on Mg2+ showed that its real substrates were Mg-ATP and free D-ribulose 5-phosphate. On the basis of results of kinetic inhibition studies and previously reported result of affinity chromatography, an ordered bi bi mechanism in which Mg-ATP binds before ribulose 5-phosphate is proposed. The Km values for ATP and D-ribulose 5-phosphate were 0.09 and 0.27 mM, respectively. Ki values of ADP and D-ribulose 1,5-bisphosphate were 0.32 and 10.0 mM, respectively. Inhibition constants Ki1 and Ki2 for 6-phosphogluconate were 9.3 and 0.49 mM. Kia was 0.13 mM. New kinetics on PRK gave higher control coefficient than the kinetics on Spinach PRK did in the model with PRK activity from 175 to 1000 µmol min–1 mg–1 chl. 相似文献
109.
Keisuke Okada Hiroyuki Abe Fumio Ike Yoshitoshi Ogura Tetsuya Hayashi Aya Fukui-Miyazaki Keiji Nakamura Naoaki Shinzawa Yasuhiko Horiguchi 《PloS one》2015,10(2)
Bordetella bronchiseptica is a pathogenic bacterium causing respiratory infections in a broad range of mammals. Recently, we determined the whole genome sequence of B. bronchiseptica S798 strain isolated from a pig infected with atrophic rhinitis and found four single-nucleotide polymorphisms (SNPs) at positions -129, -72, +22, and +38 in the region upstream of dnt encoding dermonecrotic toxin (DNT), when compared with a rabbit isolate, RB50. DNT is known to be involved in turbinate atrophy observed in atrophic rhinitis. Immunoblotting, quantitative real-time PCR, and β-galactosidase reporter assay revealed that these SNPs resulted in the increased promoter activity of dnt and conferred the increased ability to produce DNT on the bacteria. Similar or identical SNPs were also found in other pig isolates kept in our laboratory, all of which produce a larger amount of DNT than RB50. Our analysis revealed that substitution of at least two of the four bases, at positions -72 and +22, influenced the promoter activity for dnt. These results imply that these SNPs are involved in the pathogenicity of bordetellae specific to pig diseases. 相似文献
110.