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51.
棉花黄萎病是真菌病害,病原菌为大丽轮枝菌(Vertillium daliae),因致病力不同可分为不同的致病类型或生理小种。据统计,黄萎病对棉花的危害有逐年加重的趋势。1993年是我国棉花黄萎病大发生的一年,发病面积约占全国棉田的一半以上。尤其是北方棉区受害更重,重病棉田棉花病株率在80%以上,其中落叶成光秆的病株率高达50%,损失皮棉达1亿公斤。新疆棉区由于种植面积不断扩大(2000年皮棉总产占全国的1/3以上),引种不规范和  相似文献   
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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   
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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   
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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   
57.

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   
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The complete mitogenome of Haliotis iris, an economically important shellfish endemic to New Zealand, was sequenced for the first time. The mitogenome was 17,131?base pairs (bp) in length and contained 13 protein-coding genes (PCGs), 2 ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes and a control region. All 13 genes were initiated by the start codon ATG, except for nad5 (ATA). Two typical stop codons, TAA and TAG, were present. All of the tRNAs could be folded into typical cloverleaf secondary structures except tRNASer1 and tRNALys, which lacked a DHU stem and complete amino acid acceptor stem, respectively. The control region was 1132?bp in length and contained six AT tandem repeats. According to the gene order of the mitogenome, the 30 analysed Vetigastropoda species could be classified into three types—type I: over half of the studied species were very similar to the gastropod ancestral gene order, and the rearrangements occurred in five tRNAs; type II: eight species were found to be missing several tRNA genes; type III: Fissurellidae, Lepetodrilidae showed a large inverted fragment.  相似文献   
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