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11.
Sun J  Dou Y  Ding H  Yang R  Sun Q  Xiao Q 《Marine drugs》2012,10(4):881-889
4-Amino-7-(5'-deoxy-β-D-xylofuranosyl)-5-iodo-pyrrolo[2,3-d]pyrimidine 1, an unusual naturally occurring marine nucleoside isolated from an ascidan, Diplosoma sp., was synthesized from D-xylose in seven steps with 28% overall yield on 10 g scale. The key step was Vorbrüggen glycosylation of 5-iodo-pyrrolo[2,3-d]pyrimidine with 5-deoxy-1,2-O-diacetyl-3-O-benzoyl-D-xylofuranose. Its absolute configuration was confirmed.  相似文献   
12.
研究板蓝根质量与土壤因子的相关性,筛选影响其质量的主导因子。HPLC法测定甘肃不同产地板蓝根核苷类、告依春有效成分的含量,理化分析法进行土壤因子(有机质,PH,全氮,铵态氮,硝态氮,全磷,速效磷,全钾,速效钾)的测定,应用相关分析及灰色关联度分析进行综合分析。结果表明尿苷与速效钾的相关系数为-0.828*;腺苷与全钾的相关系数为-0.863**;告依春与全氮的相关系数为-0.800*,告依春与铵态氮的相关系数为-0.772*。鸟苷和告依春中铵态N的关联系数最大,分别为0.9444和0.9559;尿苷中,pH值的关联系数最大,为0.9505;腺苷中全氮的关联系数最大,为0.8609;上述所有成分中,全P、全K的关联系数均次之。无论选择土壤,还是生产中施肥,应重视和合理使用N、P和K条件对板蓝根质量的影响。  相似文献   
13.
We explored the influence of nucleoside by‐products (NBP) on blood chemistry, immune response, oxidative stress and intestinal morphology of Seriola dumerili. Four experimental diets were formulated where diets 1–3 are semipurified and supplemented with liquid NBP at concentration of 0 (D1, negative control), 30 (D2) and 90 (D3) g/kg. Diet 4 (D4) is a fishmeal‐based positive control diet. Each diet was randomly allocated to triplicate groups of fish for 50 days. The results revealed a significant influence of NBP supplementations on total cholesterol, blood urea nitrogen and triglyceride level. Lysozyme activity (LA), total serum protein (TSP) and peroxidase activity (PA) also increased with NBP supplementation as compared to the negative control. TSP, PA and LA were numerically higher in diet groups D2 and D4, respectively. Anterior enterocyte height (hE) was higher in diet group D4, while NBP‐supplemented groups showed intermediate values with D1 group and negative control group showed significantly lowest value. Supplementation of NBP also increased anterior fold height (hF) and microvillus height and posterior hF, hE and microvillus height compared with D1. Finally, we concluded that NBP can be used as a cheaper nucleotide/nucleoside source for amberjack. Supplementation of more than 30 g/kg in diets improved blood chemistry, non‐specific immunity, oxidative stress resistance and intestinal morphology of amberjack.  相似文献   
14.
灵芝有效化学成分的研究   总被引:21,自引:0,他引:21  
王磊  张云 《中国食用菌》1997,16(1):8-11
本文从灵芝有效化学成分的结构,提取分离方法,结构鉴定,生理活性及应用价值等方面进行了概述。  相似文献   
15.
[目的]优化滇重楼核苷的提取工艺条件,为滇重楼资源的开发和利用提供技术支持.[方法]以滇重楼根茎为试验材料,6种核苷类物质(胞苷、尿苷、鸟苷、胸苷、腺苷和2'-脱氧腺苷)总提取量为考察指标,采用高效液相色谱法测定其提取量,先分析超声波提取法和热水浸提法对滇重楼核苷提取效果的影响,然后在单因素试验的基础上,以甲醇体积分数、料液比、提取时间和提取次数为考察因素,采用L9(34)正交试验对滇重楼核苷类物质提取工艺进行优化,确定最佳工艺条件.[结果]超声波提取法得到的滇重楼根茎中6种核苷类物质总提取量高于热水浸提法;4个因素对滇重楼核苷总提取量的影响排序为甲醇体积分数>提取时间>提取次数>料液比,最佳提取工艺条件为:以纯净水(甲醇体积分数为0)为提取溶剂,在料液比1:10(g/mL)、30℃条件下超声波提取60 min,提取2次,得到滇重楼根茎中胞苷、尿苷、鸟苷、胸苷、腺苷和2'-脱氧腺苷的总提取量为1.4216±0.0198 mg/g,高于理论值1.3434 mg/g.[结论]正交试验优化得到的滇重楼核苷超声波提取工艺操作简便、稳定可靠,较热水浸透法的提取效率高,适合用于滇重楼核苷的提取.  相似文献   
16.
草鱼呼肠孤病毒GCRV-GD108株VP5蛋白功能及免疫原性分析   总被引:3,自引:2,他引:1  
在前期研究中分离到一株草鱼呼肠孤病毒,GCRV-GD108,并获得其全基因组序列.该病毒株的M5基因编码VP5蛋白,该蛋白与哺乳动物正呼肠孤病毒μ2蛋白具有较高的同源性及相似的NTPase结合保守区域,推测VP5蛋白也同样具有NTPase活性.为检测VP5蛋白是否具有NTPase活性及其是否具有免疫保护作用,采用已构建的原核表达载体表达VP5重组蛋白,通过孔雀绿钼酸铵法检测纯化后的重组蛋白的NTPase活性.采用DNAstar软件预测M5基因编码蛋白的抗原性,综合蛋白亲水性、表面可及性与表面抗原性三项指标,预测编码蛋白可形成抗原表位的氨基酸区域数多达86个,提示VP5蛋白具有较强的免疫原性.用重组蛋白VP5免疫健康草鱼,通过人工攻毒实验检测VP5蛋白的免疫保护作用.结果显示,VP5重组蛋白具有NTPase活性,且其NTPase活性依赖于Mg2+或Na+/K+,而Ca2+的存在可能抑制其活性;VP5蛋白可诱导草鱼产生高水平的抗体滴度,并显著提高IgM mRNA的表达水平,但未能为草鱼提供抗GCRV感染的保护.研究首次证实GCRV-GD108株VP5蛋白具有NTPase活性,但不能为草鱼提供免疫保护作用.  相似文献   
17.
In order to explore the influence of nucleoside diphosphate kinase B (NDPK B) on replication and proliferation of F48E9 strain of Newcastle disease virus (NDV), the eukaryotic expression plasmid pEGFP-NDPK B was transfected into Vero cells,then we got the cell subclones by G418 screening. We identified the expression of NDPK B protein by RT-PCR, Western blotting and inverted flurescence microscope. On the basis of Vero/NDPK B cell line,we explored the influence of NDPK B on replication and proliferation of F48E9 strain of NDV by HA-HI, TCID50 and Real-time PCR.The results showed that we had successfully constructed the cell line named Vero/NDPK B, which could stably express NDPK B protein, and found that NDPK B could inhibit the replication and proliferation of F48E9 strain of NDV in Vero cells.It suggested that on the basis of NDPK B,we could design and develop new drugs or antiviral synergist to prevent or treat NDV.  相似文献   
18.
参照GenBank中禽源核苷二磷酸激酶2(NME2)基因序列,设计了NME2基因的特异性引物。采用RT-PCR扩增NME2基因,经双酶切后克隆到真核表达载体pEF1α-Myc,得到重组质粒pEF1α-Myc-NME2。将构建好的重组质粒pEF1α-Myc-NME2转染DF1细胞后,采用间接免疫荧光和Western blot技术对目的蛋白进行验证。结果表明,Myc-NME2融合蛋白在DF1细胞内得到了正确表达。本研究为后续研究禽源NME2基因的功能奠定了基础。  相似文献   
19.
为研究核苷二磷酸激酶B(nucleoside diphosphate kinase B,NDPK B)蛋白表达对新城疫病毒(Newcastle disease virus,NDV) F48E9株复制与增殖的影响,本试验将真核表达重组质粒pEGFP-NDPK B转染Vero细胞,经G418压力筛选出了阳性细胞单克隆,并通过RT-PCR、Western blotting和倒置荧光显微镜观察鉴定了NDPK B mRNA和蛋白质的表达,在细胞系基础上,通过HA-HI、TCID50及实时荧光定量PCR检测NDPK B蛋白对NDV F48E9株复制和增殖的影响。结果表明,试验成功地构建了高表达NDPK B蛋白的Vero/NDPK B细胞系,并在此基础上,通过检测证明了NDPK B能抑制NDV F48E9株在Vero细胞中的复制与增殖,提示以NDPK B为基础有可能设计开发抗NDV的新药物或抗病毒增效剂,对NDV进行预防或治疗。  相似文献   
20.
Neoplastic lymphocytes from a horse with lymphosarcoma and IgM deficiency were analyzed for ability to grow in culture; surface and cytoplasmic IgM; functional activity in blastogenesis, cytoxicity, and suppressor assays; and activities of six enzymes involved in purine and pyrimidine metabolism. The cells lacked surface and cytoplasmic IgM. They had elevated activity of adenosine deaminase and reduced activity of purine nucleoside phosphorylase. Neoplastic cells were nonresponsive in blastogenesis assay and did not kill allogeneic lymphocyte target cells or YAC-1 targets in a lectin-dependent cytotoxicity assay, however, the cells were active in a suppressor assay. They were grown for 16 weeks in cultures supplemented with interleukin 2, during which time the cells retained suppressive activity. These results are consistent with a T cell lymphoma of suppressor cell origin, and may explain the deficiency of IgM observed in some horses with lymphoreticular neoplasms.  相似文献   
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