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101.
昆虫性信息素共轭二烯的合成进展   总被引:1,自引:0,他引:1  
许多昆虫性信息素具有共轭二烯的结构,它们的双键位置和几何构型是决定其生物活性的重要因素。立体选择性和区域选择性地合成共轭二烯是有机合成中十分有意义的研究课题。文章综述了昆虫性信息素共轭二烯的合成进展。  相似文献   
102.
Abstract

Objectives: The objective of this study was the investigation of age- and sex-associations in a set of blood plasma metabolites in healthy male and female subjects.

Methods: A comparison study design with male and female subjects of various ages was used. Metabolic profiling was performed using electrospray ionization tandem mass spectrometry that yielded 186 metabolite concentrations for each study participant. The key age-related metabolites were identified using an integrative analysis of absolute concentrations, metabolite ratios and the differential correlation of pairwise metabolite concentrations. All of the age-associated metabolites were adjusted prior to the analysis to account for differences in Body Mass Index (BMI).

Results: A total of 236 plasma samples from 140 female and 96 male subjects aged 20 to 82 years-old were collected and analyzed in the study. 13 and 14 age-associated metabolites (|r|?>?0.33 and p < 6.6×10?5), 438 and 337 age-associated metabolite ratios (|r|?>?0.37 and p < 3.5×10?6), and 5 and 10 core metabolites were discovered in the female and male groups, respectively. 80% of the metabolites displaying associations with age belonged to sphingolipids and phosphatidylcholines, and the two sexes shared less than 50% of the age-associated metabolites.

Conclusion: The study found that changes in metabolite concentrations, metabolite ratios and differential correlations were age and sex-specific.  相似文献   
103.
刘瑾  李真 《应用化学》2001,18(12):998-1000
性信息素;甘薯象鼻虫信息素(E)-2-丁烯酸-(Z)-3-十二烯基酯的全合成  相似文献   
104.
在家兔皮下埋植褪黑激素丸,每周一次,共7周.结果表明,褪黑激素对家兔性器官起抑制作用:公兔睾丸重量减轻,分泌的睾酮减少;母兔卵巢变小,血浆孕酮水平降低,卵巢发育不良,母兔无发情表现  相似文献   
105.
甘蔗条螟(Chilo venosatus walker)属鳞翅目螟蛾科,广布于我国南方蔗区,尤其在珠江兰角州高产蔗区每年发生4~6代。它使甘蔗枯心或枯梢,影响甘蔗产量。若用杀虫剂防  相似文献   
106.
Components of the Grapholitha molesta sex pheromone, (Z/E)-8-dodecenyl acetates (1, 2), were synthesized in five steps in 20% overall yield using 10-hydroxydecanoic acid (3) as starting material. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 592–594, November–December, 2006.  相似文献   
107.
The relationship between nanoparticle size, charge, shape, and in vivo biodistribution is of great importance for the rational design and selection of intravenously administered nanoparticles. A resource that aids in the selection and design of nanomaterials for this purpose would be a valuable tool. Previous literature reviews have examined narrow categories of nanomaterials or have not statistically analyzed a broad range of nanomaterial literature. Here, data regarding the biodistribution of intravenously administered synthetic and organic nanomaterials in animal models from literature available in PubMed is collected. This work outlines the effect of nanoparticle size, charge, shape, animal sex, and animal disease status on biodistribution of intravenously administered nanomaterials. Particle size and charge are found to significantly and independently influence biodistribution to several organs. Finally, animal sex and disease state are observed to function as effect modifiers for biodistribution.  相似文献   
108.
Imperatorin, a naturally derived furanocoumarin, exerts promising neuropharmacological properties. Therefore, it might be applicable in the treatment of brain diseases such as depression. In the present project, we aimed to investigate the sex-dependent effects of imperatorin (1, 5, and 10 mg/kg) on behavior and neurochemistry associated with antidepressant effects. The depressive-like behaviors of male and female Swiss mice were investigated in a forced swim test (FST). Subsequently, High-Performance Liquid Chromatography (HPLC) was used to evaluate the level of serotonin, its metabolite, 5-HIAA, and noradrenaline, in mouse brains. The study revealed that only males responded to imperatorin (1 and 5 mg/kg) treatment and caused an antidepressant effect, such as with respect to depressive-like behaviors, lowering immobility time and increasing immobility latency. The HPLC analysis demonstrated that serotonin levels in the prefrontal cortex of females decreased with the middle dose of imperatorin (5 mg/kg), while in the male prefrontal cortex, the lower dose (1 mg/kg) boosted serotonin levels. There were no evident changes observed with respect to noradrenaline and serotonin metabolite levels in the male hippocampus. To conclude, we propose that imperatorin has antidepressant potential, seemingly only in males, influencing brain serotonin level, but the direct mechanism of action requires further investigation.  相似文献   
109.
桃潜蛾性信息素的合成研究   总被引:2,自引:0,他引:2  
(-)-莰烷磺内酰胺手性助剂与巴豆酸酰氯作用生成N-反式丁烯酰基衍生物(4),进而与n-C~4H~9MgBr进行Michael加成反应,发现在CuBr.Me~2S存在下,产物以S构型为主,且化学产率明显提高。经六步合成了桃潜蛾性信息素(S)-14-甲基-1-十八碳烯(1)及其对映异构体(R)-1。  相似文献   
110.
3,7-二甲基-2-十三碳醇乙酸酯的全合成   总被引:1,自引:0,他引:1  
松叶蜂;性信息素;3;7-二甲基-2-十三碳醇乙酸酯的全合成  相似文献   
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