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61.
62.
Coloninae is a tiny and distinctive subfamily of the highly diverse family Leiodidae (round fungus and small carrion beetles). Although only one leiodid fossil is known from the Mesozoic, its taxonomic position and classification are doubtful. We describe the first definitive Coloninae fossil, Colon burmiticum Yamamoto sp. nov., from Upper Cretaceous amber of Myanmar. Our finding sheds light on the origin and early evolutionary history of this peculiar genus and its subfamily. 相似文献
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64.
Yuki Yasumoto Hirofumi Miyazaki Linda Koshy Vaidyan Yoshiteru Kagawa Majid Ebrahimi Yui Yamamoto Masaki Ogata Yu Katsuyama Hirokazu Sadahiro Michiyasu Suzuki Yuji Owada 《PloS one》2016,11(1)
Cellular metabolic changes, especially to lipid metabolism, have recently been recognized as a hallmark of various cancer cells. However, little is known about the significance of cellular lipid metabolism in the regulation of biological activity of glioma stem cells (GSCs). In this study, we examined the expression and role of fatty acid synthase (FASN), a key lipogenic enzyme, in GSCs. In the de novo lipid synthesis assay, GSCs exhibited higher lipogenesis than differentiated non-GSCs. Western blot and immunocytochemical analyses revealed that FASN is strongly expressed in multiple lines of patient-derived GSCs (G144 and Y10), but its expression was markedly reduced upon differentiation. When GSCs were treated with 20 μM cerulenin, a pharmacological inhibitor of FASN, their proliferation and migration were significantly suppressed and de novo lipogenesis decreased. Furthermore, following cerulenin treatment, expression of the GSC markers nestin, Sox2 and fatty acid binding protein (FABP7), markers of GCSs, decreased while that of glial fibrillary acidic protein (GFAP) expression increased. Taken together, our results indicate that FASN plays a pivotal role in the maintenance of GSC stemness, and FASN-mediated de novo lipid biosynthesis is closely associated with tumor growth and invasion in glioblastoma. 相似文献
65.
Y Yui R Hattori K Kosuga H Eizawa K Hiki C Kawai 《The Journal of biological chemistry》1991,266(19):12544-12547
Nitric oxide (NO) synthase (EC 1.14.23) has been purified to apparent homogeneity from rat macrophages. The purification procedure involves affinity chromatography with adenosine 2',5'-diphosphate-agarose and gel filtration chromatography on a Superose 12 HR 10/30 column. The apparent molecular weight is 300,000 by gel filtration. On polyacrylamide gel electrophoresis in sodium dodecyl sulfate, the enzyme migrates as a single protein band with Mr = 150,000. The purified enzyme is colorless, and an absorption maximum is observed at 280 nm. The half-life of the enzyme activity is 6 h at pH 7.4 and 4 degrees C. The enzyme activity required the presence of NADPH, (6R)-5,6,7,8-tetrahydro-L-biopterin, and dithiothreitol. Although the cerebellar and endothelial enzyme require Ca2+ and calmodulin, these are not required by the macrophage enzyme. The macrophage nitric oxide synthase (an inducible enzyme) seems to be different from the cerebellar and endothelial enzyme (a constitutive enzyme). 相似文献
66.
The resistance or susceptibility of Biomphalaria glabrata strains to strains of Schistosoma mansoni, the human blood fluke, are evidenced by the responses of snail hemocytes to sporocysts of the schistosome, both in vivo and in vitro. It is now reported that living sporocysts of the PR1 strain of S. mansoni agglutinate in the plasma of all tested strains of B. glabrata, in contrast to fixed sporocysts which agglutinate only in plasma from resistant snail strains. The agglutinating activity in resistant plasmas is not divalent cation dependent, and was not inhibited by the 26 carbohydrates and four amino acids tested. In addition, the observation that gelatinous deposits develop on transforming miracidia-sporocysts in B. glabrata plasmas is also reported. Both the agglutination and gel-formation phenomena may facilitate recognition of, and attacks on, sporocysts, thereby contributing to susceptibility and resistance in this host-parasite system. 相似文献
67.
Tamami Nakano Kyoko Tanaka Yuuki Endo Yui Yamane Takahiro Yamamoto Yoshiaki Nakano Haruhisa Ohta Nobumasa Kato Shigeru Kitazawa 《Proceedings. Biological sciences / The Royal Society》2010,277(1696):2935-2943
Eye tracking has been used to investigate gaze behaviours in individuals with autism spectrum disorder (ASD). However, traditional analysis has yet to find behavioural characteristics shared by both children and adults with ASD. To distinguish core ASD gaze behaviours from those that change with development, we examined temporo-spatial gaze patterns in children and adults with and without ASD while they viewed video clips. We summarized the gaze patterns of 104 participants using multidimensional scaling so that participants with similar gaze patterns would cluster together in a two-dimensional plane. Control participants clustered in the centre, reflecting a standard gaze behaviour, whereas participants with ASD were distributed around the periphery. Moreover, children and adults were separated on the plane, thereby showing a clear effect of development on gaze behaviours. Post hoc frame-by-frame analyses revealed the following findings: (i) both ASD groups shifted their gaze away from a speaker earlier than the control groups; (ii) both ASD groups showed a particular preference for letters; and (iii) typical infants preferred to watch the mouth rather than the eyes during speech, a preference that reversed with development. These results highlight the importance of taking the effect of development into account when addressing gaze behaviours characteristic of ASD. 相似文献
68.
Two linear plasmid-like DNA elements simultaneously maintained in Pleurotus ostreatus 总被引:1,自引:0,他引:1
Two linear plasmid-like DNA elements, designated pLP01 and pLP02, have been isolated from a strain of Pleurotus ostreatus, an edible basidiomycete. pLP01 (10.0 kb) and pLP02 (9.4 kb) were found in mitochondrial preparations of the fungus and appear to have 5' ends blocked by association of a protein. Proteinase K cleavability of the 5'-terminal protein of pLP01 was higher than that of pLP02, indicating that the terminal proteins of both plasmid-like elements are distinct from one another. pLP01 and pLP02 were estimated to be present to the extent of 1-2 copies each per mitochondrial genome equivalent. The two plasmid-like elements had no homology between them and also were not homologous with the mitochondrial and nuclear genomic DNAs of the fungus. 相似文献
69.
The photocatalytic activity of titanium dioxide is widely utilized in science and technology. In the biological field, titanium dioxide is believed to be a disinfectant because it produces reactive oxygen species (ROS). However, there are multiple types of ROS such as hydroxyl radicals, superoxide anions, singlet oxygen, and hydrogen peroxide. In this study, we attempted to characterize the various mechanisms and roles of ROS in disinfection. Surprisingly, we found that titanium dioxide protected yeast cells from ultraviolet irradiation. We characterized the ROS produced under these conditions. The production of hydroxyl radicals and superoxide anions was confirmed; however, glucose in the yeast medium scavenged hydroxyl radicals. The photocatalytic activity of titanium dioxide produced oxidative products and reductive products, as oxidation and reduction occurred simultaneously. Once hydroxyl radicals are scavenged, the photocatalytic activity of titanium dioxide produces a reductive environment for fermenting yeast cells and protects them from oxidative stress by ultraviolet irradiation. 相似文献