理解的对吗？ 对应的对吗？

Moderately severe as defined above but not remitting after 6 to 12 mo of therapy, or proliferative disease with impaired renal function and fibrinoid necrosis or crescents in >25% of glomeruli, or mixed membranous and proliferative nephritis, or proliferative nephritis with high chronicity alone or in combination with high activity (chronicity index >4 or chronicity index >3 and activity index >10), or rapidly progressive glomerulonephritis (doubling of serum creatinine within 2 to 3 mo)

以上定义的中度严重但在治疗6至12个月后仍未缓解、或伴有肾功能受损和纤维素样坏死的增殖性疾病或>25%的肾小球有新月体、或混合性膜性和增殖性肾炎、高度慢性化的增值性肾炎(慢性指数>4）伴或不伴高活动(慢性指数>3和活动指数>10)、快速进行性肾小球肾炎(2-3个月内血肌酐增加一倍)

 alone or in combination with理解的对吗？

chronicity index >4 or chronicity index >3 and activity index >10  对应的对吗？