Great earthquakes of Chinese mainland and its vicinity usually cluster in certain regions during certain periods. We call it major regions of great earthquakes, or major regions briefly in this paper.The major regions...Great earthquakes of Chinese mainland and its vicinity usually cluster in certain regions during certain periods. We call it major regions of great earthquakes, or major regions briefly in this paper.The major regions of different periods can migrate through long distance in space. We have studied mechanism of formation of major regions. It is proposed that the ductile layer of the lithosphere is the place where the major regions form, and deformation of the ductile layer controls the locations and shape of major regions. and the actions of the plate boundaries around the continent are the main driving forces. A two-dimensional viscoelastic finite element model is established to model the deformation field and Stress field of the Chinese mainland and its vicinity The boundary of the model is divided into 12 segments to represent non-uniform of boundary conditions. The stress concentration areas in the continental ductile Iayer are simulated under various compoundings of different boundary scgments. Six models are worked out in which the stress con centration regions are consistent with the realistic major regions. It is proved that stress concentfation regions can be produced in the ductile layer which are roughly in agreement with the realistic major regions under various actions of different boundary segments.展开更多
Objective To investigate the frequency of t(14; 18) in different subtypes of B-cell lymphomas and the ability or the polymerase chain reaction(PCR) to detect this rearrangement in frozen samples. Methods 1o7 cases of ...Objective To investigate the frequency of t(14; 18) in different subtypes of B-cell lymphomas and the ability or the polymerase chain reaction(PCR) to detect this rearrangement in frozen samples. Methods 1o7 cases of B-cell lymphomas were studied uslng DNA extracted from rresh-frozen tissues. The DNA samples were amplified by PCR for bcl-2 MBR/JH. The products of bcl-2/JH rearrangement were hybridized with an internal olignucleotide probe or bcl-2 MBR. Results The rearranged bcl-2MBR/JH gene was detected in 13 of the 25(52. o% ) follicular center lymphomas, according to REAL classification: 8 of 11 (72. 7%) grade 1, 2 of 5(40. 0%) grade I, and 3 of 90 (33. 3%) grade, 17 of 82(2o. 8%) cases or difruse large B-cell lymphomas were found to have detectable bel-2 MBR/J. rearrangement- Conclusion The rrequency or bcl-2 MBR/JH rearrangement in diffuse large B-cell lymphomas is significantly lower than those in follicular center lympkomas(X2= 9. 28, P <o. oo5), suggesting that bcl2/JH rearrangements occur mainly in follicular center lymphomas. in addition, the result of reconstruction experiments suggest that amplification or bcl-2 MBR/JH rearrangements by PCR is both sensitive and specific for detection of t (14; 18 ) translocation.展开更多
采用PHA体内注射肾细胞直接制片法及银染法研究真鲷和黑鲷的核型及Ag—NOR带。指出这两种鱼的核型公式分别为2n=48,2st+46t,NF=48和2n=48,4m+4sm+2st+38t,NF=56。两种鱼的核型中各自唯一的一对亚端部着丝点染色体(st染色体)为典型的具...采用PHA体内注射肾细胞直接制片法及银染法研究真鲷和黑鲷的核型及Ag—NOR带。指出这两种鱼的核型公式分别为2n=48,2st+46t,NF=48和2n=48,4m+4sm+2st+38t,NF=56。两种鱼的核型中各自唯一的一对亚端部着丝点染色体(st染色体)为典型的具次缢痕的染色体。银染结果显示该次缢痕部位即为银染核仁组织者区域(Ag—Nucleolusorganizer regions NORs),并表现出多态性。同时,在这两种鱼的中期分裂相中普遍观察到了NORs联合现象。此外,还讨论了这两种鱼的亲缘关系和鲷科鱼类中两个类群及其核型的分化问题,认为从细胞遗传学角度看,鲷科鱼类的两个类群在演化过程中是分支进化的。展开更多
文摘Great earthquakes of Chinese mainland and its vicinity usually cluster in certain regions during certain periods. We call it major regions of great earthquakes, or major regions briefly in this paper.The major regions of different periods can migrate through long distance in space. We have studied mechanism of formation of major regions. It is proposed that the ductile layer of the lithosphere is the place where the major regions form, and deformation of the ductile layer controls the locations and shape of major regions. and the actions of the plate boundaries around the continent are the main driving forces. A two-dimensional viscoelastic finite element model is established to model the deformation field and Stress field of the Chinese mainland and its vicinity The boundary of the model is divided into 12 segments to represent non-uniform of boundary conditions. The stress concentration areas in the continental ductile Iayer are simulated under various compoundings of different boundary scgments. Six models are worked out in which the stress con centration regions are consistent with the realistic major regions. It is proved that stress concentfation regions can be produced in the ductile layer which are roughly in agreement with the realistic major regions under various actions of different boundary segments.
文摘Objective To investigate the frequency of t(14; 18) in different subtypes of B-cell lymphomas and the ability or the polymerase chain reaction(PCR) to detect this rearrangement in frozen samples. Methods 1o7 cases of B-cell lymphomas were studied uslng DNA extracted from rresh-frozen tissues. The DNA samples were amplified by PCR for bcl-2 MBR/JH. The products of bcl-2/JH rearrangement were hybridized with an internal olignucleotide probe or bcl-2 MBR. Results The rearranged bcl-2MBR/JH gene was detected in 13 of the 25(52. o% ) follicular center lymphomas, according to REAL classification: 8 of 11 (72. 7%) grade 1, 2 of 5(40. 0%) grade I, and 3 of 90 (33. 3%) grade, 17 of 82(2o. 8%) cases or difruse large B-cell lymphomas were found to have detectable bel-2 MBR/J. rearrangement- Conclusion The rrequency or bcl-2 MBR/JH rearrangement in diffuse large B-cell lymphomas is significantly lower than those in follicular center lympkomas(X2= 9. 28, P <o. oo5), suggesting that bcl2/JH rearrangements occur mainly in follicular center lymphomas. in addition, the result of reconstruction experiments suggest that amplification or bcl-2 MBR/JH rearrangements by PCR is both sensitive and specific for detection of t (14; 18 ) translocation.
文摘采用PHA体内注射肾细胞直接制片法及银染法研究真鲷和黑鲷的核型及Ag—NOR带。指出这两种鱼的核型公式分别为2n=48,2st+46t,NF=48和2n=48,4m+4sm+2st+38t,NF=56。两种鱼的核型中各自唯一的一对亚端部着丝点染色体(st染色体)为典型的具次缢痕的染色体。银染结果显示该次缢痕部位即为银染核仁组织者区域(Ag—Nucleolusorganizer regions NORs),并表现出多态性。同时,在这两种鱼的中期分裂相中普遍观察到了NORs联合现象。此外,还讨论了这两种鱼的亲缘关系和鲷科鱼类中两个类群及其核型的分化问题,认为从细胞遗传学角度看,鲷科鱼类的两个类群在演化过程中是分支进化的。