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Anti-inflammatory therapy approaches have been in the focus of attention in the treatment of neurodegenerative diseases, such as Alzheimer's disease (AD). In this study, we examined the role of new 1,2,4-triazine derivatives against cytotoxicity exerted by lipopolysaccharide (LPS) in differentiated rat pheochromocytoma (PC12) cell line. Our results indicated that LPS-induced cell death can be inhibited in the presence of some of these compounds, as measured by MTT test, acridine orange/ethidium bromide staining and caspase-3 expression assay. We further showed that these compounds exert their protective effects through the inhibition of LPS-induced generation of nitric oxide and reactive oxygen species. Triazine derivatives inhibited LPS-induced nuclear translocation of nuclear factor- κB, a known regulator of a host of genes involved in specific stress and inflammatory responses. Pretreatment of PC12 cells with triazine derivatives also suppressed LPS-induced cyclooxygenase-2 expression while up-regulated heat shock protein-70 (Hsp-70). Moreover, the treatment of brain diseases is limited by the insufficiency in delivering therapeutic drugs into brain relating to highly limited transport of compounds through blood-brain barrier (BBB). Using a reliable model based on the artificial neural network, we indicated that these compounds are capable of penetrating BBB and may be useful agents for preventing neuroinflammatory diseases like AD.  相似文献   
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We have performed genome-wide expression profiling of endocrine regulation of genes expressed in the mouse initial segment (IS) and distal caput of the epididymis by using Affymetrix microarrays. The data revealed that of the 15 020 genes expressed in the epididymis, 35% were enriched in one of the two regions studied, indicating that differential functions can be attributed to the IS and the more distal caput regions. The data, furthermore, showed that 27% of the genes expressed in the IS and/or distal caput epididymidis are under the regulation of testicular factors present in the duct fluid, while bloodborne androgens can regulate for 14% of them. This is in line with the high testis dependency of epididymal physiology. We then focused on genes with moderate or strong expression, showing strict segment enrichment and strong dependency on testicular factors. Analyses of the 59 genes, including upregulated and downregulated genes, fulfilling the criteria indicated that the expression of 18 (17 downregulated genes; 1 upregulated gene) of 19 gonadectomy-responsive genes enriched in the IS was not maintained by the androgen treatment, whereas the expression of all six downregulated genes enriched in the distal caput and the majority of those with no strict segment enrichment of expression (28 of 34; consisting of 23 downregulated and 5 upregulated genes) were maintained by androgens. Hence, it is evident that testicular factors other than androgens are important for the expression of IS-enriched genes, whereas the expression of distal caput-enriched genes is typically regulated by androgens. Identical data were obtained by independent clustering analyses performed for the expression data of 3626 epididymal genes. Several novel genes with putative involvement in epididymal sperm maturation, such as a disintegrin and metallopeptidase domain 28 (Adam28) and a solute carrier organic anion transporter family, member 4C1 (Slco4c1), were identified, indicating that this approach is successful for identifying novel epididymal genes.  相似文献   
156.

Background  

The relationship between functional recovery after brain injury and concomitant neuroplastic changes is emphasized in recent research. In the present study we aimed to delineate brain regions essential for language performance in aphasia using functional magnetic resonance imaging and acquisition in a temporal sparse sampling procedure, which allows monitoring of overt verbal responses during scanning.  相似文献   
157.
Gene expression QTL (eQTL) mapping can suggest candidate regulatory relationships between genes. Recent advances in mammalian phenotype annotation such as mammalian phenotype ontology (MPO) enable systematic analysis of the phenotypic spectrum subserved by many genes. In this study we combined eQTL mapping and phenotypic spectrum analysis to predict gene regulatory relationships. Five pairs of genes with similar phenotypic effects and potential regulatory relationships suggested by eQTL mapping were identified. Lines of evidence supporting some of the predicted regulatory relationships were obtained from biological literature. A particularly notable example is that promoter sequence analysis and real-time PCR assays support the predicted regulation of protein kinase C epsilon (Prkce) by cAMP responsive element binding protein 1 (Creb1). Our results show that the combination of gene eQTL mapping and phenotypic spectrum analysis may provide a valuable approach to uncovering gene regulatory relations underlying mammalian phenotypes.  相似文献   
158.
Synthesis and in vivo evaluation of 2-{4-[4-(3-methoxyphenyl)piperazin-1-yl]-butyl}-4-methyl-2H-[1,2,4]triazine-3,5-dione (5 or MMT), a high affinity and selective serotonin 5-HT1AR agonist PET tracer, are described. GTPgammaS assay shows that MMT is an agonist with an EC50 comparable to 5-HT. Radiolabeling of 5 was achieved in 30% yield (EOS) from desmethyl-MMT (4) with >99% chemical and radiochemical purities and a specific activity >1000 Ci/mmol. PET studies in baboon show that [11C]5 penetrates the blood-brain barrier but, because of low specific binding and fast clearance of radioactivity it is not a suitable PET tracer for the in vivo quantification of 5-HT1AR.  相似文献   
159.
QSAR studies indicated that the potency of nifedipine analogues was dependent upon lipophilicity, an electronic term and separated terms for each position on the DHP ring. Changes in the substitution pattern at the C3, C4, and C5 positions of DHPs alter potency, tissue selectivity, and the conformation of the 1,4-DHP ring. In this project a group of alkyl ester analogues of new derivatives of nifedipine, in which the ortho-nitrophenyl group at position 4 is replaced by a 1-methyl-5-nitro-2-imidazolyl substituent, and the methyl group at position 6 is replaced by a phenyl substituent, were synthesized and evaluated as calcium channel antagonist using the high K+ contraction of guinea-pig ileal longitudinal smooth muscle. The results for asymmetrical esters showed that lengthening of the substituent in C3 ester substituent increased activity. When increasing of the length is accompanied by increasing the hindrance, the activity decreased. The results demonstrate that all compounds were more active or similar in effect to that of the reference drug nifedipine.  相似文献   
160.
A series of new aluminum(III), gallium(III) and indium(III) complexes with some tridentate Schiff base, viz., N-{pyridine-2-ylmethyl}-2-hydroxy-5-methoxy-benzylideneamine [HL1], N-{pyridine-2-ylmethyl}-2-hydroxy-benzylideneamine [HL2], N-{pyridine-2-ylmethyl}-2-hydroxy-5-nitro-benzylideneamine [HL3], N-{pyridine-2-ylmethyl}-2-hydroxy-5-bromo-benzylideneamine [HL4], N-{pyridine-2-ylethyl}-2-hydroxy-5-methoxy-benzylideneamine [HL5], N-{pyridine-2-ylethyl}-2-hydroxy-benzylideneamine [HL6], N-{pyridine-2-ylethyl}-2-hydroxy-5-nitro-benzylideneamine [HL7], N-{pyridine-2-ylethyl}-2-hydroxy-5-bromo-benzylideneamine [HL8], with the general formula [ML2][Y] (M = Al3+, Ga3+, In3+; Y = NO3, ClO4) were synthesised and characterized by elemental analysis, 1H NMR, FT-IR, UV-Vis spectrophotometry and mass spectrometry. The thermodynamic formation constants of the complexes were determined spectrophotometrically at constant ionic strength (I = 0.10 M NaClO4) and at 25 °C in methanol. The trend of formation constants of the complexes are as follow:
Al<Ga<In  相似文献   
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