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The crude extract of an endophytic fungus isolated from Syzygium cordatum and identified as Fusarium proliferatum showed 100% cytotoxicity against the brine shrimp Artemia salina at 100 μg/mL. Seven coloured, biologically active metabolites – including ergosta-5,7,22-trien-3β-ol, nectriafurone-8-methyl ether, 9-O-methyl fusarubin, bostrycoidin, bostrycoidin-9-methyl ether and 8-hydroxy-5,6-dimethoxy-2-methyl-3-(2-oxo-propyl)-1,4-naphthoquinone– were isolated from the extract.  相似文献   
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A stereoselective approach to spiro-annulated bicyclo[2.2.2]octane ring system related to the tetracyclic skeleton of daphmanidin A–type alkaloids is described. Ring-closing metathesis, Wacker oxidation, and aldol condensation are key features ofour approach. An interesting steric effect on aldol condensation has also been observed.  相似文献   
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LED组合光谱对水培生菜矿物质吸收的影响   总被引:1,自引:0,他引:1  
在植物工厂全密闭环境中水培种植大速生生菜,以光谱比例可调节的LED灯板为植物生长光源,应用电感耦合等离子体原子发射光谱技术(ICP-AES),研究了红蓝LED组合光谱下生菜对K,P,Ca,Mg,Na,Fe,Mn,Zn,Cu,B,Mo等11种营养元素的吸收特性。结果表明:(1)与叶绿素生理吸收波峰(峰值450和660 nm)对应的单一或组合光谱均可增强水培生菜根对Na, Fe, Mn, Cu, Mo元素的吸收能力,且单一红光光谱的促进作用最为显著,四种元素含量分别为荧光灯全光谱下的7.8, 4.2, 5.3, 11.0倍;(2)根对K和B元素的吸收量在荧光灯全光谱下达到最大分别为10.309 mg·g-1和32.6 μg·g-1,而在红、蓝单一或组合光谱下吸收能力降低;(3)单一蓝色光谱下根对Ca和Mg元素的吸收受到抑制,分别比荧光灯对照降低35%,33%;(4)生菜在30%蓝光+70%红光的光谱条件下生物量最高,而在20%蓝光+80%红光条件下对Ca, Mg, Na, Fe, Mn, Zn, B七种元素的累积量达到最大值。试验结果为水培生菜光源光谱选择及营养液配方调节提供了理论依据。  相似文献   
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Hyperbranched polyurethanes are synthesized using TDI, PCL diol, butanediol, and pentaerythritol (1–5 wt%) as the B4 reactant with and without the monoglyceride of sunflower oil. The biodegradation, physico‐mechanical, and thermal properties are found to be tailored by varying the percentage weight of the branching unit. An MTT/hemolytic assay and subcutaneous implantation in Wistar rats followed by cytokine/ALP assay and histopathology studies confirm a better biocompatibility of HBPU with MG than without MG. HBPU supports the proliferation of dermatocytes with no toxic effect in major organs, in addition the in vitro degraded products are non‐toxic. Cell adherence and proliferation endorse the bio‐based HBPU as a prospective scaffold material in the niche of tissue engineering.

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A stereoselective approach to tricyclic core of yaoshanenolides from simple aromatic precursor is described. Cycloaddition of highly reactive spiroepoxycyclohexa-2,4-dienone, stereoselective Grignard reaction, alkylation, and ring-closing metathesis reaction are the key features of our approach.  相似文献   
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