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排序方式: 共有1147条查询结果,搜索用时 15 毫秒
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Zajdel P Marciniec K Maślankiewicz A Paluchowska MH Satała G Partyka A Jastrzębska-Więsek M Wróbel D Wesołowska A Duszyńska B Bojarski AJ Pawłowski M 《Bioorganic & medicinal chemistry》2011,19(22):6750-6759
Novel arene- and quinolinesulfonamides were synthesized using different solutions and a solid-support methodology, and were evaluated for their affinity for 5-HT(1A), 5-HT(2A), 5-HT(6), and 5-HT(7) receptors. Compound 54 (N-Ethyl-N-[4-(1,2,3,4,4a,5,6,7,8,8a-decahydroisoquinolin-2-yl)butyl]-8-quinolinesulfonamide) was identified as potent 5-HT(7) antagonist (K(i)=13 nM, K(B)=140 nM) with good selectivity over 5-HT(1A), 5-HT(2A), 5-HT(6) receptors. In the FST in mice, it reduced immobility in a manner similar to the selective 5-HT(7) antagonist SB-269970. 相似文献
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Beata Olas Joanna Kołodziejczyk-Czepas Barbara Wachowicz Dariusz Jędrejek Anna Stochmal Wiesław Oleszek 《Central European Journal of Biology》2011,6(6):990-996
Humulus lupulus (Cannabaceae) is well known throughout the world as a raw material in the brewing industry. The antioxidative action of hop cones is poorly
understood, therefore the aim of our present study was to investigate in vitro changes in human plasma induced by peroxynitrite in the presence of the highly purified extract from hop cones (Humulus lupulus). The aim of our study was also to explain the effect of the extract from hop cones on coagulation activity of human plasma
treated with peroxynitrite. The action of the extract from hop cones was compared with the properties of a well-characterized
commercial monomeric polyphenol — resveratrol (3,4′,5-trihydroxystilbene). The tested plant extract, like resveratrol, significantly
inhibited protein carbonylation and nitration in plasma treated with ONOO−(0.1 mM). The extract from hop cones, like resveratrol, also caused a distinct reduction of plasma lipid peroxidation induced
by ONOO−. Moreover, the tested extract modulated the coagulation properties of plasma treated with peroxynitrite. It seems that antioxidative
activities of the highly purified extract from hop cones may be responsible for its medicinal properties. 相似文献
86.
The chemokine receptor CXCR3, which was shown to take part in many inflammatory processes, is considered as a Th1 specific marker. Here, we show in a mouse model that CXCR3 expressing CD4(+) cells preferentially migrate to the peritoneal cavity under steady-state conditions. The peritoneal cavity milieu leads to an up-regulated expression of CXCR3. However, blocking of known ligands of this chemokine receptor did not alter the preferential migration. The peritoneal cavity environment also results in an increased percentage of memory cells producing cytokines. Up-regulation of IFNγ production occurs mostly in CXCR3(+) cells considered as Th1, whereas the up-regulation of IL-4 affects mostly in CXCR3(-) cells which are considered as Th2. We conclude that the peritoneal cavity does not change the Th-lineage of the cells, but that domination of this anatomic niche by Th1 cells rather results from preferential migration to this compartment. 相似文献
87.
Usarek E Gajewska B Kaźmierczak B Kuźma M Dziewulska D Barańczyk-Kuźma A 《Neurochemical research》2005,30(8):1003-1007
The expression of glutathione S-transferase pi (GST pi), an enzyme responsible for inactivation of a large variety of toxic compounds was studied in spinal
cord, motor and sensory brain cortex obtained from patients who died in the course of amyotrophic lateral sclerosis (ALS).
The studies were performed on formalin-fixed, paraffin-embedded (FFPE) and freshly frozen tissues. The method of RNA isolation
from FFPE was modified. A significant decrease of GST pi-mRNA expression was found in cervical spinal cord and motor brain
cortex of ALS subjects comparing to analogue control tissues (P < 0.01), as well as in motor cortex of ALS subjects comparing to their sensory cortex (P < 0.05). In spinal cords the decrease in GST pi-mRNA expression was accompanied by a decrease of GST pi protein level. Results
indicated lowered GST pi expression on both mRNA and protein levels in the regions of nervous system affected by ALS. The
non-properly inactivated by GST toxic electrophiles and organic peroxides may thus contribute to motor neurons damage. 相似文献
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Paluchowska MH Bugno R Bojarski AJ Charakchieva-Minol S Duszyńska B Tatarczyńska E Kłodzińska A Stachowicz K Chojnacka-Wójcik E 《Bioorganic & medicinal chemistry》2005,13(4):1195-1200
Novel, flexible arylpiperazine gepirone analogs (1a-3a) with a mixed 5-HT1A/5-HT2A receptor profile, low D2 receptor affinity, and agonistic (2a) or partial agonistic (1a, 3a) activity toward 5-HT1A receptor sites were synthesized. Their conformationally restricted counterparts (1b-3b) were selective 5-HT1A ligands (over 5-HT2A and D2 receptors), which turned out to be agonists (2b, 3b), or partial agonist (1b) of 5-HT1A receptors. 相似文献
89.
Olsson M Madsen T Uller T Wapstra E Ujvari B 《Evolution; international journal of organic evolution》2005,59(1):221-225
Sex allocation theory predicts that parents should bias their reproductive investments toward the offspring sex generating the greatest fitness return. When females are the heterogametic sex (e.g., ZW in butterflies, some lizards, and birds), production of daughters is associated with an increased risk of offspring inviability due to the expression of paternal, detrimental recessives on the Z chromosome. Thus, daughters should primarily be produced when mating with partners of high genetic quality. When female sand lizards (Lacerta agilis) mate with genetically superior males, exhibiting high MHC Class I polymorphism, offspring sex ratios are biased towards daughters, possibly due to recruitment of more Z-carrying oocytes when females have assessed the genetic quality of their partners. If our study has general applicability across taxa, it predicts taxon-specific sex allocation effects depending on which sex is the heterogametic one. 相似文献