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51.
doi: 10.1111/j.1741‐2358.2011.00605.x
Effects of systemic sitafloxacin on periodontal infection control in elderly patients Objective: To evaluate the microbiological and clinical effects of the systemic administration of sitafloxacin (STFX) on periodontal pockets in elderly patients receiving supportive periodontal therapy (SPT). Background: Periodontitis is a risk factor for atherosclerosis. Better periodontal health contributes to reduce atherosclerosis‐related diseases in elderly population. Materials and methods: Forty‐four patients undergoing SPT were randomly assigned to two groups: a test group took 100 mg/day of STFX for five consecutive days, or a control group received scaling and root planing (SRP) under local anaesthesia. Microbiological and clinical parameters were examined at baseline and at 1 and 3 months after therapy. Results: The presence of Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia was significantly reduced at 1 month after treatment in both groups. The median reductions of the bacteria between the baseline and 1 month were 3.08 and 2.54% in the STFX‐ and SRP‐treated groups, respectively. Both treatments significantly decreased the probing depth at 1 and 3 months compared to the baseline. Conclusion: The systemic administration of STFX is effective at improving periodontal health during SPT and could be an alternative to SRP for elderly patients who cannot undergo anaesthesia or are at risk of tissue injury.  相似文献   
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Here, we report for the first time a comparative phosphoproteomic analysis of distinct tumor cell lines in the presence or absence of the microtubule‐interfering agent nocodazole. In total, 1525 phosphorylation sites assigned to 726 phosphoproteins were identified using LC‐MS‐based technology following phosphopeptide enrichment. Analysis of the amino acid composition surrounding the identified in vivo phosphorylation sites revealed that they could be classified into two motif groups: pSer‐Pro and pSer‐Asp/Glu. Phosphoproteomic change resulting from nocodazole treatment varied among cell lines in terms of the numbers of total phosphopeptides identified, motif groups, and functional annotation groups; however, the cell lines were equally sensitive to nocodazole. The identified phosphoproteome subset contained major signaling proteins and proteins known to be involved in mitosis, but did not always exhibit the same changes in the tumor cells from nocodazole treatment. In spite of the complex changes observed in the phosphorylation of many of the proteins, possible common features induced by nocodazole were found, including phosphorylation of nucleophosmin (NPM) S254 and coatomer protein complex, subunit α (COPA) S173, suggesting that the events are not cell‐type specific but events generally occurring in mitosis or induced by a microtubule‐interfering agent. Further, temporal analysis of phosphoproteome change revealed that phosphorylation of NPM S254 and COPA S173 was observed from the early (6 h) and late (24 h) time point after nocodazole treatment, respectively, suggesting that NPM S254 may be involved in the induction of M‐phase arrest by nocodazole, whereas COPA S173 may be caused as a result of M‐phase arrest.  相似文献   
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The primary structures of three -amylase inhibitors (TAI, DAI, and MAI-2) consisting of glycoprotein subunits and from the respective seeds of three cultivars of Phaseolus beans, Toramame (Phaseolus vulgaris L.), Daifukumame (Phaseolus vulgaris L.), and Murasakihanamame (Phaseolus coccineus L.) were determined by sequencing the peptide fragments derived from their enzymatic digestions. Major sugar chains of the inhibitors were also assessed by analyzing glycopeptides in the enzymatic digests. The subunits, and , were shown to be composed of 76 and 139 amino acid residues, respectively, in each inhibitor. The overall amino acid sequences of the inhibitors were slightly different from one another. Furthermore, the sequence of TAI was the same as that deduced from a cDNA clone encording -amylase inhibitor-1 from the common bean (Phaseolus vulgaris L.). It was also revealed that there were two N-glycosylation sites in each -subunit: PA-derivatives of the major N-glycans were estimated to be M6B at Asn(12) and M9A at Asn(65). Each -subunit of TAI and MAI-2 had two N-glycosylation sites, while the -subunit of DAI had only one site. The major N-glycans pyridylaminated were estimated to be M3X at Asn(63) in each -subunit and M3FX at Asn(83) in -subunits of TAI and MAI-2.  相似文献   
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Fission yeast cells identify growing regions at the opposite ends of the cell, producing the rod-like shape. The positioning of the growth zone(s) and the polarized growth require CLIP170-like protein Tip1 and the Ndr kinase Orb6, respectively. Here, we show that the mor2/cps12 mutation disrupts the localization of F-actin at the cell ends, producing spherical cells and concomitantly inducing a G(2) delay at 36 degrees C. Mor2 is important for the localization of F-actin at the cell end(s) but not at the medial region, and is essential for the restriction of the growth zone(s) where Tip1 targets. Mor2 is homologous to the Drosophila Furry protein, which is required to maintain the integrity of cellular extensions, and is localized at both cell ends and the medial region of the cell in an actin-dependent fashion. Cellular localization of Mor2 and Orb6 was interdependent. The tyrosine kinase Wee1 is necessary for the G(2) delay and maintenance of viability of the mor2 mutant. These results indicate that Mor2 plays an essential role in cell morphogenesis in concert with Orb6, and the mutation activates the mechanism coordinating morphogenesis with cell cycle progression.  相似文献   
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6-Sulfo-sialyl Lewis X structure is attributable to recognition between lymphocytes and high endothelial venules. However, the biosynthetic pathway still remains unclear. We found that a β-galactosyltransferase (βGalT) in human colorectal mucosa preferentially acts on GlcNAc-6-O-sulfate (6S-GN). 6S-GN:β4GalT was partially purified by UDP-hexanolamine-Sepharose and asialo-agalacto-ovomucin-Sepharose chromatographies. The optimum pH of this enzyme was found to be 6.5–7.5 and the Michaelis constants for 6S-GN and UDP-Gal were 0.43 mM and 16 μM, respectively. The enzymatic activity was dependent on divalent cations and the substrate specificity was not affected by α-lactalbumin. This is the first demonstration of the occurrence of 6S-GN:β4GalT.  相似文献   
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As a first step towards studying the biochemical relationship between Golgi vesicles (GVs) and tube wall components, isolation of GVs from the growing pollen tubes ofCamellia japonica was attempted using a centrifugation method with mannitol. The isolated GV was identified ultrastructurally and immunocytochemically. The main components of the GV were proteins and carbohydrates. The main monosaccharides of GV polysaccharides were galactose, arabinose and uronic acid, and pectins and arabinogalactan proteins also were detected immunochemically. An antiserum against the isolated GVs reacted with the outer layer of the pollen tube wall and the intine layers of the grain wall as well as thein situ GVs in the pollen tube and the grain cytoplasm. We have thus successfully isolated GVs and shown that they contain pectic substances and arabinogalactan proteins which contribute to formation of the pollen tube primary wall.  相似文献   
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During vertebrate limb development, the apical ectodermal ridge (AER) plays a vital role in both limb initiation and distal outgrowth of the limb bud. In the early chick embryo the prelimb bud mesoderm induces the AER in the overlying ectoderm. However, the direct inducer of the AER remains unknown. Here we report that FGF7 and FGF10, members of the fibroblast growth factor family, are the best candidates for the direct inducer of the AER. FGF7 induces an ectopic AER in the flank ectoderm of the chick embryo in a different manner from FGF1, -2, and -4 and activates the expression of Fgf8, an AER marker gene, in a cultured flank ectoderm without the mesoderm. Remarkably, FGF7 and FGF10 applied in the back induced an ectopic AER in the dorsal median ectoderm. Our results suggest that FGF7 and FGF10 directly induce the AER in the ectoderm both of the flank and of the dorsal midline and that these two regions have the competence for AER induction. Formation of the AER of the dorsal median ectoderm in the chick embryo is likely to appear as a vestige of the dorsal fin of the ancestors.  相似文献   
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