简介:Thispaperpresentsanewalgorithmforgenerating3DimagesofB-repsobjectswithtrimmedsurfaceboundaries.The3Dimageisadiscretevoxel-maprepresentationwithinaCubicFrameBuffer(CFB).Thedefinitionof3Dimagesforcurve,surfaceandsolidobjectareintroducedwhichimplytheconnectivityandfidelityrequirements.AdaptiveForwardDifferencingmatrix(AFD-matrix)for1D-3Dmanifoldsin3Dspaceisdeveloped.BysettingrulestoupdatetheAFD-matrix,theforwarddifferencedirectionandstepwisecanbeadjusted.Finally,anefficientalgorithmispresentedbasedontheAFD-matrixconceptforconvertingtheobjectin3Dspaceto3Dimagein3Ddiscretespace.
简介:大环内酯类抗生素基因工程是近年来生物工程领域研究的一个热点,利用基因工程改造大环内酯类抗生素合成基因,已经合成了100多种"非天然”的天然化合物,为筛选新抗生素开辟了新的途径.本研究以糖多孢红霉菌A226基因组DNA为模板,先用PCR扩增出红霉素合成基因eryKR6两侧片段,再用重叠PCR将其拼接成去除KR6的约3.2kbDNA片段,并克隆于pWHM3载体,构建了同源重组质粒pWHM2201.用PEG介导将pWHM2201转入糖多孢红霉菌A226原生质体.PCR鉴定和生物活性检测均显示pWHM2201已重组到红霉素合成基因位点.在无抗性R3M斜面上生长两代后,制备重组体原生质体,并涂R3M平皿.利用PCR筛选出KR6敲除的突变体糖多孢红霉菌M.
简介:Thedull-finishferriticstainlesssteel(FSS)sheetB445RforarchitecturalroofinghasbeendevelopedbyBaosteel.ThissteelproductexhibitsexcellentcorrosionresistancesuperiortothatofSUS316Lwithalowercost.Itcanbeeasilyformedintoroofingpanelsbyordinaryprocesses.Moreover,thethermalstrainofitislessthanSUS316Lbecauseofitslowerthermalexpansioncoefficient,anditsreflectivityislowerduetothedull-finishtreatment.Allofthesefeaturesmakeitcapableofbeingusedasarchitecturalroofingmaterialsincoastalregions.
简介:AbstractAlthough the first-line rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone regimen (R-CHOP) substantially improved outcomes for patients with diffuse large B-cell lymphoma (DLBCL), 40% of the patients suffered from relapsed/refractory disease and had poor survival outcomes. The detailed mechanism underlying R-CHOP resistance has not been well defined. For this review, we conducted a thorough search for literature and clinical trials involving DLBCL resistance. We discussed DLBCL biology, epigenetics, and aberrant signaling of the B-cell receptor (BCR), phosphatidylinositol 3-kinase (PI3K)/Akt, nuclear factor kappa light chain enhancer of activated B-cells (NF-κB), and the Janus kinase (JAK)/signal transducer and activator of transcription 3 (STAT3) pathways as defining mechanisms of DLBCL heterogeneity and R-CHOP resistance. The cell of origin, double- or triple-hit lymphoma and double-protein-expression, clonal evolution, tumor microenvironment, and multi-drug resistance help to contextualize DLBCL resistance in an (epi)genetically and biologically comparative manner. With better understanding of the biological and molecular landscape of DLBCL, a more detailed classification system and tailored treatments will ideally become available to further improve the prognosis of DLBCL patients.
简介:MYB蛋白质在真核细胞的有机体起重要作用。在植物,R1R2R3类型MYB蛋白质在房间周期控制工作。然而,R2R3类型MYB蛋白质是否也涉及房间部门过程,仍然保持未知。这里,我们报导那R2R3类型抄写因素基因,AtMYB59,涉及房间周期前进和根生长的规定。AtMYB59蛋白质在洋葱的原子核是局部性的表皮的房间并且transactivation活动。在酵母房间的AtMYB59的表示压制房间增长,和transformants与更长的房间有更多的原子核和更高的aneuploidDNA内容。在AtMYB59的保存领域的变化在酵母细胞生长上废除它的效果。在同步Arabidopsis房间暂停,AtMYB59基因明确地在房间周期前进期间在S阶段被表示。表示和promoter-GUS分析表明AtMYB59基因富有地在根被表示。转基因的植物overexpressingAtMYB59更短的根与野类型的植物(Arabidopsis就职Col-0)相比,并且在在根尖端的有丝分裂的房间的一半附近在中期。相反地,空变异的myb59-1比关口在中期让更长的根和更少有丝分裂的房间,建议那AtMYB59可以由扩大有丝分裂的房间的中期禁止根生长。AtMYB59调整许多下游的基因,包括CYCB1;1基因,可能通过到MYB应答的元素的绑定。这些结果在细胞周期规定和植物根生长为AtMYB59支持一个角色。
简介:目的建立棕背的实验室繁育方法,测定棕背生长和繁殖数据,为开展棕背实验动物化研究提供基础。方法将黑龙江省牡丹江市牡丹峰林地的野生棕背引入实验室,于大型硬壁式啮齿动物负压隔离器内进行人工饲育、繁殖,测定棕背生长和繁育数据,评价棕背实验室繁育效果。结果棕背在实验室条件下可以实现人工饲育、繁殖。妊娠率54.55%,平均妊娠期为20.4d(18~22d);一个繁殖期内平均繁殖2.9次,最高繁殖次数为7次,远远超过自然条件下所统计到的繁殖次数(1~4次);平均窝产仔数(4.3±1.22)只,单窝最高产仔数为8只;幼仔离乳率94.8%,生长发育状况良好。结论实现了棕背的实验室繁育,测定了棕背在实验室条件下的生长和繁育数据,为棕背实验动物化打下了基础。