排序方式： 共有21条查询结果，搜索用时 15 毫秒
11.
基于事件的时空数据模型应用研究 总被引：9，自引：4，他引：5
本文首先分析和比较了几种有代表性时空数据模型的特点和存在的局限性 ,对基于事件的时空数据模型进行了改进 ,并提出了利用亲缘继承关系进行历史回溯查询 ,根据具体的实际应用 ,在现有成熟的ARCGIS平台上进行扩展 ,验证了该模型的有效性。实践表明 :利用该模型可以有效的进行各种时间、空间和属性的互查 ;时间因素和空间对象的空间特征和属性信息分开存储管理 ,便于时空分析 ,适于进行地理事件与空间对象状态因果关系的推理 ;减小了数据的存储空间 ,以及数据的冗余度 相似文献
12.
利用Hoechst 33258荧光染色法检测紫外线B(UVB)辐射诱导HaCaT细胞凋亡率。结果表明,扇贝多肽(Polypeptide from Chlamys farreri,PCF)可以剂量依赖性抑制UVB诱导的HaCaT细胞凋亡;表皮生长因子受体(EGFR)抑制剂AG1478能明显抑制UVB诱导的HaCaT细胞凋亡。采用3’-RACE法构建EGFR的cDNA片段,克隆测序检测突变位点。结果表明,UVB照射后EGFR发生碱基突变A→G,A→G,T→C,G→A,G→A;预加入5.69mmol/L的PCF,产生部分抗突变作用,1,2,3突变位点处未发生碱基的突变。 相似文献
13.
Polypeptide from Chlamys farreri inhibits UVB-induced apoptosis of HaCaT cells via iNOS/NO and HSP90
Polypeptide from Chlamys farreri(PCF) is a novel marine bioactive product that was isolated from the gonochoric Chinese scallop Chlamys farreri,and was found to be an effective antioxidant in our recent studies.In this study,we investigated the effect of PCF on ultraviolet B(UVB)-induced apoptosis of HaCaT cells and the intracellular signaling pathways involved.Pretreatment with the inducible nitric oxide synthase(iNOS) inhibitor S-methylisothiourea sulfate inhibited UVB-induced apoptosis,indicating that iN... 相似文献
14.
A novel marine active polypeptide(PCF),isolated from the gonochoric Chinese scallop,Chlamys farreri,has potential antioxidant and anti-apoptotic activity against ultraviolet irradiation.We investigated whether UVB-induced HaCaT cell apoptosis occurs via the mitochondrial pathways Apaf-1/caspase-9 and Smac/XIAP/caspase-3.We then investigated the molecular mechanisms controlling the anti-apoptotic effect of PCF.Pre-treatment with PCF and caspase-9 inhibitor significantly inhibited UVB-induced apoptosis in HaC... 相似文献
15.
盐藻β–胡萝卜素对鹌鹑脂肪肝的影响 总被引：4，自引：1，他引：3
盐藻β－胡萝卜素由中国科学院海洋研究所提供,用综合法复制鹌鹑脂肪肝动物模型藻β－胡萝卜素以观察其预防高脂饱中料致鹌鹑脂肪肝的作用,分组喂在不同饲料,对肝脏进行肉眼和病理组织学检查,结果表明,Ⅱ－Ⅶ组的肝系数与Ⅰ组相比有较明显的升高,盐藻β－胡萝卜素在６．２５ｍｇ／ｋｇ－２５ｍｇ／ｋｇ剂量范围内能使肝系数降低,肝脏脂肪变程度减轻,与Ⅱ组比较有统计学意义。实验证明,自盐泽杜氏藻中提取的以顺式炙主的β－ 相似文献
16.
Protective Effect of Topically Applied Polypeptide from Chlamys farreri Against Ultraviolet Radiation-Induced Chronic Skin Damage in Guinea Pig 总被引：2，自引：0，他引：2
INTRODUCTIONSolarultraviolet(UV)radiationisknowntobeamajoretiologicalriskofphotoaging.AsUVC(2 0 0nm -2 90nm)isabsorbedentirelybythestratosphericozonelayer,sunlightontheearthsur faceiscomposedofUVA (3 2 0nm -4 0 0nm)andUVB (2 90nm -3 2 0nm)only.UVAradiationenergyaccountsformorethan 90 %ofsolarUV ;andpenetratesthebasallayerofepidermismoreefficientlythanUVB (Brulsetal.,1984) .However,atsimilardosages,UVBismuchmoremuta genicthanUVA (Drobetskyetal.,1995) .Furthermore ,humanskinisexp… 相似文献
17.
~~The Polypeptide in Chlamys farreri can protect human dermal fibroblasts from ultraviolet B damage@张玉江$Qingdao University, Medical College,Qingdao Shandong 266021,China
@战松梅$Qingdao University, Medical College,Qingdao Shandong 266021,China
@曹鹏利$Qingdao University, Medical College,Qingdao Shandong 266021,China
@刘宁$Qingdao University, Medical College,Qingdao Shandong 266021,China
@陈雪红$Qingdao University, Medical College,Qingdao Shandong 266021,China
@… 相似文献
18.
19.
20.