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61.
Well-defined lactose-containing glycopolymer has been synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization with (4-cyanopentanoic acid)-4- dithiobenozoate (CAD) as chain transfer agent. The glycopolymer was introduced onto the exterior surfaces of the bovine serum albumin (BSA) imprinted polymer beads by grafting copolymerization with methyl methacrylate and ethylene glycol dimethacrylate. After alcoholysis, the hydrophilic lactose residues of glycopolymer will stretched on the surface of the MIP beads and then the hydrophilicity of the surface will be enhanced. Rebinding test shows that the glycopolymer hydrophilic modified BSA imprinted polymer presents higher performance selectivity than that of unmodified one, which means that the hydrophobic-hydrophilic balance of the imprinted polymer surface is in favor of the improvement of specific recognition property of the material. 相似文献
62.
A strain of Paenibacillus sp., OSY-SE, was isolated from soil and found to produce a novel lipopeptide antibiotic. The antibiotic, paenibacterin, is active against Gram-negative and Gram-positive bacterial pathogens. Paenibacterin is biosynthesized by a nonribosomal peptide synthetase pathway. Here we report the draft genome sequence of Paenibacillus sp. OSY-SE. 相似文献
63.
Lingjun Hu Weibin Song Yuhui Meng Dean Guo Xuan Liu Lihong Hu 《Bioorganic & medicinal chemistry letters》2012,22(24):7547-7550
A series of 3-demethoxycarbonyl-3-acylamide methyl vinorelbine derivatives (compounds 7a–7z) were designed, synthesized, and evaluated for their inhibition activities against human non-small cell lung cancer cell line (A549). Most of the amide derivatives exhibited potent cytotoxicity, with the size of the introduced substituents being the foremost factor in determining the resultant cytotoxic activity. Test results in vivo against nude mice bearing A549 xenografts indicated that 7y showed comparable activities compared to the parent NVB. 相似文献
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Wei Guo Wenfeng Liu Lingjian Zhu Yongqiang Zhang Pengfei Cheng Guoqiang Dong Chunlin Zhuang Jianzhong Yao Chunquan Sheng Zhenyuan Miao Wannian Zhang 《化学与生物多样性》2011,8(8):1539-1549
Homocamptothecin (hCPT) is an E‐ring modified camptothecin (CPT) analogue, which showed pronounced inhibitory activity of topoisomerase I. In search of novel hCPT‐type anticancer agents, two series of hCPT derivatives were synthesized and evaluated in vitro against three human tumor cell lines. The results indicated that the 10‐substituted hCPT derivatives had a considerably higher cytotoxic activity than the 12‐substituted ones. Among the 10‐substituted compounds, 8a, 8b, 9b , and 9i showed an equivalent or even more potent activity than the positive control drug topotecan against the lung cancer cell line A‐549. Moreover, the hCPT analogues 8a and 8b exhibited a higher topoisomerase I inhibitory activity than CPT at a concentration of 100 μM . 相似文献
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M. Dong F. Guo J. Yang S. Liu Z. Tao Y. Fang C. Zhang J. Li G. Li 《Netherlands heart journal》2013,21(4):175-180
Objective
Traditionally, oestrogens were considered to be protective for the cardiovascular system for premenopausal women. Therefore, we conducted a retrospective case–control study to examine the association between endogenous oestrogens and acute myocardial infarction (AMI) risk among postmenopausal women.Methods
A case–control study was performed among 30 primary AMI patients and 60 control subjects. Baseline characteristics data was collected and endogenous sex hormones levels were determined using chemoluminescence and radioimmunoassay methods. Conditional logistic regression models were developed with adjustment for confounders.Results
Compared with controls, the circulating oestrone, oestradiol, androstenedione and testosterone levels were significantly higher in AMI patients (P < 0.05) while the sex hormone binding globulin (SHBG) level was lower (P < 0.05). Spearman correlation coefficients showed oestradiol was positively correlated with body mass index (BMI) and waist-to-hip ratio (WHR) in cases, but not in controls. In univariable conditional logistic regression models, oestrone, oestradiol, testosterone, WHR, BMI, diabetes and hypertension were all found to be positively associated with AMI (P < 0.05). After adjusting for these factors, oestradiol (odds ratio (OR) = 4.75; 95 % confidence interval (CI) = 1.07–21.10; P = 0.04) and WHR (OR = 6.46; 95 % CI = 1.09–38.39; P = 0.04) continued to demonstrate strong positive associations with AMI.Conclusions
A higher level of oestradiol was potentially associated with primary AMI risk among postmenopausal women. 相似文献69.
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