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911.
Mitsuyama K Tomiyasu N Takaki K Masuda J Yamasaki H Kuwaki K Takeda T Kitazaki S Tsuruta O Sata M 《Mediators of inflammation》2006,2006(6):26875
Using a specific enzyme-linked immunosorbent assay, IL-10 concentrations were measured in serum from 62 patients with ulcerative colitis (UC), 43 with Crohn's disease (CD), 25 with other colitides, and 44 normal control subjects. Serum IL-10 concentrations were increased in patients with active UC but not in those with active CD when compared with normal control subjects. A time course study showed that in patients with UC and CD, serum concentrations of IL-6 and C-reactive protein increased during the acute phase and returned to normal as patients go into remission. Notably, serum IL-10 concentrations increased during the phase of disease resolution and declined thereafter regardless of the treatment modality. Gel filtration analysis indicated that IL-10 circulated predominantly as a dimer. In conclusion, this study shows that serum IL-10 is increased during disease recovery in patients with inflammatory bowel disease, and may be a helpful marker in monitoring disease status. 相似文献
912.
Imaginal disc growth factor (IDGF) is a soluble polypeptide growth factor that was first identified from the conditioned medium of Drosophilia imaginal disc C1.8+ cells. Working with insulin, IDGF stimulated the growth of cultured imaginal disk cells, which suggested that IDGF might function as a cofactor of Drosophila insulin or insulin like peptide. Here we report a new member of the IDGF family, named MbIDGF, from the cabbage armyworm, Mamestra brassicae. Using a cloned cDNA of MbIDGF, recombinant MbIDGF protein was expressed in baculovirus-infected Sf9 cells and purified. Without insulin, the recombinant MbIDGF protein stimulated cell growth of SES-MaBr-4 and NIAS-MaBr-93 cell lines that were derived from the fat bodies and hemocytes of M. brassicae, in a dose-dependent manner. The saturation of growth stimulation by MbIDGF was attained for the two types of cells at 80 ng/ml (0.8 nM) and 300 ng/ml (6 nM), respectively. The results suggest that MbIDGF may stimulate the growth of lepidopteran cells by a new mechanism without associating with the insulin pathway. 相似文献
913.
Phosphorylation of tau at Ser214 mediates its interaction with 14-3-3 protein: implications for the mechanism of tau aggregation 总被引:1,自引:0,他引:1
Golam Sadik Toshihisa Tanaka Kiyoko Kato Hidenaga Yamamori Begum Nurun Nessa Takashi Morihara Masatoshi Takeda 《Journal of neurochemistry》2009,108(1):33-43
The microtubule associated protein tau is a major component of neurofibrillary tangles in Alzheimer disease brain, however the neuropathological processes behind the formation of neurofibrillary tangles are still unclear. Previously, 14-3-3 proteins were reported to bind with tau. 14-3-3 Proteins usually bind their targets through specific serine/threonine –phosphorylated motifs. Therefore, the interaction of tau with 14-3-3 mediated by phosphorylation was investigated. In this study, we show that the phosphorylation of tau by either protein kinase A (PKA) or protein kinase B (PKB) enhances the binding of tau with 14-3-3 in vitro . The affinity between tau and 14-3-3 is increased 12- to 14-fold by phosphorylation as determined by real time surface plasmon resonance studies. Mutational analyses revealed that Ser214 is critical for the phosphorylation-mediated interaction of tau with 14-3-3. Finally, in vitro aggregation assays demonstrated that phosphorylation by PKA/PKB inhibits the formation of aggregates/filaments of tau induced by 14-3-3. As the phosphorylation at Ser214 is up-regulated in fetal brain, tau's interaction with 14-3-3 may have a significant role in the organization of the microtubule cytoskeleton in development. Also as the phosphorylation at Ser214 is up-regulated in Alzheimer's disease brain, tau's interaction with 14-3-3 might be involved in the pathology of this disease. 相似文献
914.
The Temperature-Sensitive brush Mutant of the Legume Lotus japonicus Reveals a Link between Root Development and Nodule Infection by Rhizobia
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Makoto Maekawa-Yoshikawa Judith Müller Naoya Takeda Takaki Maekawa Shusei Sato Satoshi Tabata Jillian Perry Trevor L. Wang Martin Groth Andreas Brachmann Martin Parniske 《Plant physiology》2009,149(4):1785-1796
The brush mutant of Lotus japonicus exhibits a temperature-dependent impairment in nodule, root, and shoot development. At 26°C, brush formed fewer nodules, most of which were not colonized by rhizobia bacteria. Primary root growth was retarded and the anatomy of the brush root apical meristem revealed distorted cellular organization and reduced cell expansion. Reciprocal grafting of brush with wild-type plants indicated that this genotype only affected the root and that the shoot phenotype was a secondary effect. The root and nodulation phenotype cosegregated as a single Mendelian trait and the BRUSH gene could be mapped to the short arm of chromosome 2. At 18°C, the brush root anatomy was rescued and similar to the wild type, and primary root length, number of infection threads, and nodule formation were partially rescued. Superficially, the brush root phenotype resembled the ethylene-related thick short root syndrome. However, treatment with ethylene inhibitor did not recover the observed phenotypes, although brush primary roots were slightly longer. The defects of brush in root architecture and infection thread development, together with intact nodule architecture and complete absence of symptoms from shoots, suggest that BRUSH affects cellular differentiation in a tissue-dependent way. 相似文献
915.
The effects of starvation on cell death in the midgut of Periplaneta americana were studied histochemically and ultrastructurally. TUNEL assays showed that cell death began to increase in the columnar
cells and nidi, the nests of stem cells and newborn cells from 2 weeks of starvation. A significant increase in cell death
occurred in the nidi after 4 weeks of starvation. Cockroaches starved for 4 weeks showed active-caspase-3-like immuno-reactivity
both in the columnar cells and nidi, whereas control cockroaches that were fed for 4 weeks showed this reactivity only in
the apical cytoplasm of columnar cells. Electron microscopy revealed no chromatin condensation in the nucleus of columnar
cells of cockroaches, whether fed or starved for 4 weeks. Starved cockroaches exhibited many small vacuoles in the cytoplasm
of some columnar cells and “floating” organelles including nuclei in the lumen. A 4-week starvation induced the appearance
of cytoplasmic fragmentation and secondary lysosomes in the nidi. Each fragment contained nuclear derivatives with condensed
chromatin, i.e. apoptotic bodies. Mitotic cells were found in some, but not all nidi, even within the same starved sample.
Fragmentation was not observed in the nidi of control cockroaches. Thus, starvation increases cell death not only in the columnar
cells, but also in the nidi. The cell death in the nidi is presumably apoptosis executed by caspase 3. 相似文献
916.
Masahiko Nakamura Takayuki Hamasaki Maiko Tokitou Masanori Baba Yuichi Hashimoto Hiroshi Aoyama 《Bioorganic & medicinal chemistry》2009,17(13):4740-4746
Adult T cell leukemia (ATL), caused by infection of human T-lymphotropic virus type 1 (HTLV-1), has a poor prognosis and curative therapy is unavailable, so it is important to find or design superior lead compounds for the drug treatment of ATL. We used our micro-reversed fragment-based drug design hypothesis and multi-template hypothesis to extract the tetrahydrotetramethylnaphthalene (TMN) skeleton from tamibarotene, a useful medicament for the treatment of acute promyelocytic leukemia (APL). Structural development of TMN yielded highly ATL cell-selective growth inhibitors, including 2-acetyl-3-hydroxy-5,6,7,8-tetrahydro-5,5,8,8-tetramethylnaphthalene (6). Structure–activity relationship analysis suggests the existence of a specific target molecule for ATL cell-selective inhibition of proliferation through G2 arrest. 相似文献
917.
918.
Tomohiko Urano Takahiko Usui Shizu Takeda Atsushi Okada Yoshiko Ishida Jun Otomo Satoshi Inoue 《Biochemical and biophysical research communications》2009,383(2):263-251
Terf/TRIM17 is a member of the TRIM family of proteins, which is characterized by the RING finger, B-box, and coiled-coil domains. In the present study, we found that terf interacts with TRIM44. Terf underwent ubiquitination in vitro in the presence of the E2 enzyme UbcH6; this suggests that terf exhibits E3 ubiquitin ligase activity. It was also found that terf was conjugated with polyubiquitin chains and stabilized by the proteasome inhibitor in mammalian cells; this suggested that terf rendered itself susceptible to proteasomal degradation through polyubiquitination. We also found that TRIM44 inhibited ubiquitination of terf, and thus stabilized the protein. The N-terminal region of TRIM44 contains a zinc-finger domain found in ubiquitin hydrolases (ZF UBP) and ubiquitin specific proteases (USPs). Thus, we proposed that TRIM44 may function as a new class of the “USP-like-TRIM” which regulates the activity of associated TRIM proteins. 相似文献
919.
Atsushi Nagai Takeshi Maruyama Kohsuke Takeda Hidenori Ichijo 《Biochemical and biophysical research communications》2009,379(4):995-1000
Accumulation of unfolded proteins within the endoplasmic reticulum (ER) lumen induces ER stress. Eukaryotic cells possess the ER quality control systems, the unfolded protein response (UPR), to adapt to ER stress. IRE1α is one of the ER stress receptors and mediates the UPR. Here, we identified ubiquitin specific protease (USP) 14 as a binding partner of IRE1α. USP14 interacted with the cytoplasmic region of IRE1α, and the endogenous interaction between USP14 and IRE1α was inhibited by ER stress. Overexpression of USP14 inhibited the ER-associated degradation (ERAD) pathway, and USP14 depletion by small interfering RNA effectively activated ERAD. These findings suggest that USP14 is a novel player in the UPR by serving as a physiological inhibitor of ERAD under the non-stressed condition. 相似文献
920.
Yoshikazu Fujii Hiroki Kabumoto Tadashi Fujii Koji Takeda Akira Arisawa Tomohiro Tamura 《Biochemical and biophysical research communications》2009,385(2):170-8310
Vitamin D3 (VD3) is a fat-soluble prohormone that plays a crucial role in bone metabolism, immunity, and control of cell proliferation and cell differentiation in mammals. The actinomycete Pseudonocardia autotrophica is capable of bioconversion of VD3 into its physiologically active forms, namely, 25(OH)VD3 or 1α,25(OH)2VD3. In this study, we isolated and characterized Vdh (vitamin D3 hydroxylase), which hydroxylates VD3 from P. autotrophica NBRC 12743. The vdh gene encodes a protein containing 403 amino acids with a molecular weight of 44,368 Da. This hydroxylase was found to be homologous with the P450 belonging to CYP107 family. Vdh had the same ratio of the Vmax values for VD3 25-hydroxylation and 25(OH)VD3 1α-hydroxylation, while other enzymes showed preferential regio-specific hydroxylation on VD3. We characterized a collection of Vdh mutants obtained by random mutagenesis and obtained a Vdh-K1 mutant by the combination of four amino acid substitutions. Vdh-K1 showed one-order higher VD3 25-hydroxylase activity than the wild-type enzyme. Biotransformation of VD3 into 25(OH)VD3 was successfully accomplished with a Vdh-expressed recombinant strain of actinobacterium Rhodococcus erythropolis. Vdh may be a useful enzyme for the production of physiologically active forms of VD3 by a single cytochrome P450. 相似文献