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111.
Short synthetic oligodeoxynucleotides (ODNs) rich in CpG or GpG motifs have been considered as potential modulators of immunity in clinical settings. In this study, we show that a synthetic GpC-ODN conferred highly suppressive activity on mouse splenic plasmacytoid dendritic cells, demonstrable in vivo in a skin test assay. The underlying mechanism involved signaling by noncanonical NF-κB family members and TGF-β-dependent expression of the immunoregulatory enzyme IDO. Unlike CpG-ODNs, the effects of GpC-ODN required TLR7/TRIF-mediated but not TLR9/MyD88-mediated events, as do sensing of viral ssRNA and the drug imiquimod. Induction of IDO by a GpC-containing ODN could also be demonstrated in human dendritic cells, allowing those cells to assist FOXP3(+) T cell generation in vitro. Among potentially therapeutic ODNs, this study identifies GpC-rich sequences as novel activators of TLR7-mediated, IDO-dependent regulatory responses.  相似文献   
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In pursuing our research on some 2,4-diamino-benzopyranopyrimidines and 2-amino-5,6-dihydrobenzo[h]quinazolines, previously reported as antiplatelet and analgesic/anti-inflammatory agents respectively, we designed and synthesized a new series of 5,6-dihydrobenzo[h]quinazoline 2,4-diamino substituted. The insertion of amino substituents at positions 2 and 4 of the benzoquinazoline scaffold resulted in compounds endowed with a potent ASA-like antiplatelet activity, combined with an anti-inflammatory activity comparable, in some cases, to that of indomethacin, used as a reference drug.  相似文献   
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The present study was conducted to evaluate the effect of 2-phenylethynyl-butyltellurium (PEBT), an organotellurium compound, at doses of 5 and 10 mg/kg on memory, employing the step-down inhibitory avoidance task in mice. Moreover, the involvement of glutamate uptake and release in cerebral cortex and hippocampus of mice was investigated. A single oral administration (p.o.) of PEBT at the dose of 10 mg/kg 1h before training (acquisition), immediately after training (consolidation) or 1 h before the test session (retrieval) of the step-down inhibitory avoidance task increased the step-through latency time in comparison to the control mice. In the open-field test, no significant differences in the number of crossings and rearings were observed among groups. The [(3)H]glutamate uptake by cerebral cortex and hippocampal slices of mice was significantly inhibited after 1h of treatment with PEBT. After 24h of PEBT exposure, only the hippocampal [(3)H]glutamate uptake was inhibited. The [(3)H]glutamate release by cerebral cortex and hippocampal synaptosomes of mice was not altered. These results suggest that PEBT improved memory stages (acquisition, consolidation and retrieval) in the step-down inhibitory avoidance task in mice. The improvement of memory by PEBT seems most likely to be mediated through an interaction with the amino acid transporters of the glutamatergic system.  相似文献   
114.
Shoot apices of in vitro-grown plantlets of white mulberry, Morus alba L. cv Florio, were cryopreserved using either encapsulation-dehydration or vitrification. For encapsulation-dehydration, alginate beads containing apices were dehydrated for 1, 3, 5 or 7 days in a liquid medium containing various sucrose concentrations (0.5, 0.75, 1.0 or 1.25 M). Bead desiccation was performed using silica gel for either 0, 4, 6, 8, 9 or 14 h. For vitrification, apices were directly immersed for either 5, 15, 30 or 60 min in a vitrification solution (PVS2). Following encapsulation-dehydration, treatment of alginate beads with 0.75 M sucrose was more effective in promoting re-growth of explants after immersion in liquid nitrogen than in the presence of 0.5 M sucrose for either 1 or 3 days. Re-growth of explants was also observed following vitrification and this reached 47% with increasing duration of the PVS2 treatment from 5 to 30 min. Overall, the highest frequency of explant re-growth was obtained when explants were subjected to encapsulation-dehydration in the presence of 0.75 M along with a 3 day sucrose dehydration pre-treatment and followed by desiccation for 9 h in silica gel.  相似文献   
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Alveolar formation or alveolarization is orchestrated by a finely regulated and complex interaction between growth factors and extracellular matrix proteins. The lung parenchyma contains various extracellular matrix proteins including proteoglycans, which are composed of glycosaminoglycans (GAGs) linked to a protein core. Although GAGs are known to regulate growth factor distribution and activity according to their degree of sulfation the role of sulfated GAG in the respiratory system is not well understood. The degree of sulfation of GAGs is regulated in part, by sulfatases that remove sulfate groups. In vertebrates, the enzyme Sulfatase-Modifying Factor 1 (Sumf1) activates all sulfatases. Here we utilized mice lacking Sumf1(-/-) to study the importance of proteoglycan desulfation in lung development. The Sumf1(-/-) mice have normal lungs up until the onset of alveolarization at post-natal day 5 (P5). We detected increased deposition of sulfated GAG throughout the lung parenchyma and a decrease in alveolar septa formation. Moreover, stereological analysis showed that the alveolar volume is 20% larger in Sumf1(-/-) as compared to wild type (WT) mice at P10 and P30. Additionally, pulmonary function test was consistent with increased alveolar volume. Genetic experiments demonstrate that in Sumf1(-/-) mice arrest of alveolarization is independent of fibroblast growth factor signaling. In turn, the Sumf1(-/-) mice have increased transforming growth factor β (TGFβ) signaling and in vivo injection of TGFβ neutralizing antibody leads to normalization of alveolarization. Thus, absence of sulfatase activity increases sulfated GAG deposition in the lungs causing deregulation of TGFβ signaling and arrest of alveolarization.  相似文献   
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We used proteomic approach to analyze the protein profile of human follicular fluid (HFF) obtained from 25 normo-ovulatory women undergoing assisted reproduction techniques due to a male infertility factor. In all HFF samples analyzed we found 695 common spots distributed in the 3 to 10 pH range and in the 10-200 kDa range. Only 625 of these spots were also present in the plasma. We used MALDI-TOF-MS analysis to unequivocally assign 183 HFF/plasma matched spots and 27 HFF/plasma unmatched spots. A large number of acute-phase proteins, including transferrin, ceruloplasmin, afamin, hemopexin, haptoglobin and plasma amyloid protein, were identified in HFF in relatively high concentration supporting the hypothesis that mammalian ovulation can be compared to an inflammatory event. We also identified several important antioxidant enzymes; i.e., catalase, superoxide dismutase, glutathione transferase, paraoxonase, heat shock protein 27 and protein disulfide isomerase. This indicates that during maturation the human follicle is well protected against toxic injury due to oxidative stress.  相似文献   
120.
Olive trees have a plentiful bloom but a low percentage of normal fruit set. To improve fruit set, numerous investigations have sought to identify the obstacles that prevent full production. In this work, flower development in five DOP Umbria cultivars (Leccino, Frantoio, Moraiolo, Dolce Agogia and San Felice) was studied throughout different developmental phases, from before microsporogenesis and megasporogenesis to post-anthesis, by morphological and cyto-histological observations. Dolce Agogia was the most precocious cultivar, while full flowering was simultaneous in Leccino, Frantoio, Moraiolo and San Felice. Frantoio and Leccino were also good pollen producers, having the highest percentage of pollen viability and germinability. Dolce Agogia can also be considered a good pollen producer in terms of the high quantity of released pollen, but it had the lowest levels of pollen viability and germinability and the highest percentage of aborted flowers and ovaries. Morphological and cyto-histological observations on the number of flowers per inflorescence and the number of aborted flowers and ovaries suggest that fruit set was not influenced by the number of flowers per inflorescence, but rather by the number of inflorescences, which depends on the global fruiting potential of the tree.  相似文献   
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