| 1. | The virulent strains had a polysaccharide capsule and formed smooth colonies on agar medium .
有毒菌株具有多糖荚膜它在琼脂培养基上形成光滑的菌落。 |
| 2. | Some virulent strains of pvx cause rugosity go the leaves even crinkling, called pvx crinkle .
PVX的有些强毒株系引起叶子的粗缩甚至皱缩，叫做PVX皱缩。 |
| 3. | Its mortality rate , in its most virulent strains , is 90 %
就有毒菌株而言，死亡率高达90 % 。 |
| 4. | Its mortality rate , in its most virulent strains , is 90 %
最致命的病毒株引起的死亡率达到90 % 。 |
| 5. | Its mortality rate , in its most virulent strains , is 90 %
由于该病毒含有剧毒的菌株，因此它的致死率为90 % 。 |
| 6. | Health experts are worried that a new , more virulent strain may be to blame
卫生专家考虑这归咎于一种毒力更强的新菌种。 |
| 7. | Deaths could be dramatically higher if the next pandemic virus is a very virulent strain
若病毒毒性较强，死亡的人数更可能大幅上升。 |
| 8. | Some virulent strains of pvx cause rugosity go the leaves even crinkling , called pvx crinkle
Pvx的有些强毒株系引起叶子的粗缩甚至皱缩，叫做pvx皱缩。 |
| 9. | This result indicated that the virus pd70344v derived from the infectious molecular clone is a highly virulent strain which had inherited main characters from its parental virus dv
这一结果说明本文所构建的感染性分子克隆株pd70344v具有其亲本dv株的基本生物学性状，是一株具有高致病力的衍生病毒。 |
| 10. | Two amino acid substitutions near the vp2 - vp4 cleavage site were identified in the virulent strain jz2000 and might be involved in increased virulence of the virus . phylogenetic analyses indicated that these two strains were most closely related to some european strains but distinct from wibdv and variant strains
分子系统进化树分析表明， zj2000株和jd1株与cu - 1 、 p2 、 cef94 、 harbin等毒株的关系最近，而与欧洲、香港、日本的超强毒株和美国的变异株相对较远。 |
