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71.
Seiji Sugimoto Yoshiharu Yokoo Noritaka Hatakeyama Akira Yotsuji Sadao Teshiba Hiroshi Hagino 《Biotechnology letters》1991,13(6):385-388
Summary Higher culture pH of 7.6 was shown to be preferable for the inclusion body formation of salmon growth hormone (SGH) inEscherichia
coli harboring a recombinant plasmid. High-level formation of SGH inclusion bodies was achieved at 33°C (pH 7.6). Growth inhibition by soluble SGH was also observed. 相似文献
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73.
Naoki Tokuhara Kana Namiki Mai Uesugi Chihiro Miyamoto Makoto Ohgoh Katsutoshi Ido Takashi Yoshinaga Toshihiko Yamauchi Junro Kuromitsu Sadao Kimura Norimasa Miyamoto Yoshitoshi Kasuya 《The Journal of biological chemistry》2010,285(43):33294-33306
One of the family of voltage-gated calcium channels (VGCC), the N-type Ca2+ channel, is located predominantly in neurons and is associated with a variety of neuronal responses, including neurodegeneration. A precise mechanism for how the N-type Ca2+ channel plays a role in neurodegenerative disease, however, is unknown. In this study, we immunized N-type Ca2+ channel α1B-deficient (α1B−/−) mice and their wild type (WT) littermates with myelin oligodendrocyte glycoprotein 35–55 and analyzed the progression of experimental autoimmune encephalomyelitis (EAE). The neurological symptoms of EAE in the α1B−/− mice were less severe than in the WT mice. In conjunction with these results, sections of the spinal cord (SC) from α1B−/− mice revealed a reduction in both leukocytic infiltration and demyelination compared with WT mice. No differences were observed in the delayed-type hypersensitivity response, spleen cell proliferation, or cytokine production from splenocytes between the two genotypes. On the other hand, Western blot array analysis and RT-PCR revealed that a typical increase in the expression of MCP-1 in the SC showed a good correlation with the infiltration of leukocytes into the SC. Likewise, immunohistochemical analysis showed that the predominant source of MCP-1 was activated microglia. The cytokine-induced production of MCP-1 in primary cultured microglia from WT mice was significantly higher than that from α1B−/− mice and was significantly inhibited by a selective N-type Ca2+ channel antagonist, ω-conotoxin GVIA or a withdrawal of extracellular Ca2+. These results suggest that the N-type Ca2+ channel is involved in the pathogenesis of EAE at least in part by regulating MCP-1 production by microglia. 相似文献
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75.
Does genomic variation in a foundation species predict arthropod community structure in a riparian forest? 下载免费PDF全文
Shinnosuke Kagiya Masaki Yasugi Hiroshi Kudoh Atsushi J. Nagano Shunsuke Utsumi 《Molecular ecology》2018,27(5):1284-1295
Understanding how genetic variation within a foundation species determines the structure of associated communities and ecosystem processes has been an emerging frontier in ecology. Previous studies in common gardens identified close links between intraspecific variation and multispecies community structure, and these findings are now being evaluated directly in the complex natural ecosystem. In this study, we examined to what extent genomic variation in a foundation tree species explains the structure of associated arthropod communities in the field, comparing with spatial, temporal and environmental factors. In a continuous mixed forest, arthropods were surveyed on 85 mature alders (Alnus hirsuta) in 2 years. Moreover, we estimated Nei's genetic distance among the alders based on 1,077 single nucleotide polymorphisms obtained from restricted‐site‐associated DNA sequencing of the alders’ genome. In both years, we detected significant correlations between genetic distance and dissimilarity of arthropod communities. A generalized dissimilarity modelling indicated that the genetic distance of alder populations was the most important predictor to explain the variance of arthropod communities. Among arthropod functional groups, carnivores were consistently correlated with genetic distance of the foundation species in both years. Furthermore, the extent of year‐to‐year changes in arthropod communities was more similar between more genetically closed alder populations. This study demonstrates that the genetic similarity rule would be primarily prominent in community assembly of plant‐associated arthropods under temporally and spatially variable environments in the field. 相似文献
76.
Tadaaki Kishi Masato Kato Toshiyuki Shimizu Keiko Kato Kazumasa Matsumoto Shigetaka Yoshida Sadao Shiosaka Toshio Hakoshima 《Journal of structural biology》1997,118(3):248-251
Neuropsin (Mr25 032) is a serine protease expressed in the limbic system of mouse brain. It has been implicated in various neurological processes including formation of memory and may be important as a drug target in the treatment of epilepsy. The recombinant protein was produced using a baculovirus expression system and was purified. Two crystal forms were obtained by a hanging-drop vapor-diffusion method with polyethylene glycol. Preliminary X-ray crystallographic analysis revealed that crystal form I belongs to triclinic space groupP1 with unit cell dimensionsa= 97.16 Å,b= 97.12 Å,c= 46.75 Å and α = 99.17°, β = 99.77°, γ = 117.35°. Self-rotation function analysis of these data of form I indicates the position of a noncrystallographic threefold axis. There are six molecules in the crystallographic asymmetric unit. Crystal form II also belongs to triclinic space groupP1 but has unit cell dimensions ofa= 38.40 Å,b= 55.16 Å,c= 65.37 Å and α = 95.38°, β = 89.98°, γ = 110.46° with two molecules in the crystallographic asymmetric unit. Form II has a noncrystallographic twofold axis. Intensity data to 3.1 Å resolution for form I and to 2.2 Å resolution for form II have been collected. 相似文献
77.
R4/B subfamily RGS (regulator of G protein signaling) proteins play roles in regulation of many GPCR-mediated responses. Multiple RGS proteins are usually expressed in a cell, and it is difficult to point out which RGS protein species are functionally important in the cell. To evaluate intrinsic potency of these RGS proteins, we compared inhibitory effects of RGS1, RGS2, RGS3, RGS4, RGS5, RGS8 and RGS16 on AT1 receptor signaling. Intracellular Ca2+ responses to angiotensin II were markedly attenuated by transiently expressed RGS2, RGS3 and RGS8, compared to weak inhibition by RGS1, RGS4, RGS5 and RGS16. N-terminally deleted RGS2 (RGS2 domain) lost this potent inhibitory effect, whereas RGS domains of RGS3 and RGS8 showed strong inhibition similar to those of the full-length proteins. To investigate key determinants that specify the differences in potency, we constructed chimeric domains by replacing one or two of three exon parts of RGS8 domain with the corresponding part of RGS5. The chimeric RGS8 domains containing the first or the second exon part of RGS5 showed strong inhibitory effects similar to that of wild type RGS8, but the chimeric domain with the third exon part of RGS5 lost its activity. On the contrary, replacement of the third exon part of RGS5 with the corresponding residues of RGS8 increased the inhibitory effect. The role of the third exon part of RGS8 domain was further confirmed with the chimeric RGS8/RGS4 domains. These results indicate the potent inhibitory activity of RGS8 among R4/B subfamily proteins and importance of the third exon. 相似文献
78.
Mutation Rate and Dominance of Genes Affecting Viability in DROSOPHILA MELANOGASTER 总被引:10,自引:28,他引:10
Spontaneous mutations were allowed to accumulate in a second chromosome that was transmitted only through heterozygous males for 40 generations. At 10-generation intervals the chromosomes were assayed for homozygous effects of the accumulated mutants. From the regression of homozygous viability on the number of generations of mutant accumulation and from the increase in genetic variance between replicate chromosomes it is possible to estimate the mutation rate and average effect of the individual mutants. Lethal mutations arose at a rate of 0.0060 per chromosome per generation. The mutants having small effects on viability are estimated to arise with a frequency at least 10 times as high as lethals, more likely 20 times as high, and possibly many more times as high if there is a large class of very nearly neutral mutations.-The dominance of such mutants was measured for chromosomes extracted from a natural population. This was determined from the regression of heterozygous viability on that of the sum of the two constituent homozygotes. The average dominance for minor viability genes in an equilibrium population was estimated to be 0.21. This is lower than the value for new mutants, as expected since those with the greatest heterozygous effect are most quickly eliminated from the population. That these mutants have a disproportionately large heterozygous effect on total fitness (as well as on the viability component thereof) is shown by the low ratio of the genetic load in equilibrium homozygotes to that of new mutant homozygotes. 相似文献
79.
Synergistic antitumor effects of interleukin-12 gene transfer and systemic administration of interleukin-18 in a mouse bladder cancer model 总被引:2,自引:0,他引:2
Kazuki Yamanaka Isao Hara Hiroshi Nagai Hideaki Miyake Kazuo Gohji Mark J. Micallef Masashi Kurimoto Soichi Arakawa Sadao Kamidono 《Cancer immunology, immunotherapy : CII》1999,48(6):297-302
We introduced the interleukin-12 (IL-12) gene into the mouse bladder cancer cell line (MBT2) to establish sublines that secrete
bioactive IL-12. IL-12-secreting MBT2 (MBT2/IL-12) sublines were completely rejected when subcutaneously implanted into immunocompetent
syngeneic C3H mice. Although this antitumor effect did not change when IL-12-secreting cells were injected into immunodeficient
mice whose CD8+ T or CD4+ T cells had been depleted by the corresponding antibody, it was abrogated when natural killer cells were depleted by anti-asialoGM1
antibody. In addition, when parental MBT2 cells mixed with MBT2/IL-12 cells were subcutaneously injected into mice, admixed
MBT2/IL-12 inhibited the growth of the parental tumor. Furthermore, this antitumor effect was enhanced by systemic IL-18 administration.
This synergism was abrogated when the mice were treated with interferon-γ-neutralizing antibody in vivo. In conclusion, local
secretion of IL-12 led to effective antitumor activity that was enhanced by systemic administration of IL-18. Interferon-γ
plays an important role in the synergism of IL-12 gene transduction and systemic administration of IL-18.
Received: 7 May 1998 / Accepted: 27 May 1999 相似文献
80.