Vascular cambium has formed, but the secondary structure is far from developed.

The mechanism for the initiation and activity of vascular cambium

维管形成层发生和活动的机理

Cambium The ring of dividing cells ( meristem) responsible for lateral growth in plants.

和植物生长有关的具有分裂能力的细胞层。

While for older roots, there are periderm, secondary phloem, cambium, secondary xylem and primary xylem. In root, the duct caliber of xylem in Akebia quinata ( Thunb.) Decne.

老根由外向内依次为：周皮、次生韧皮部、形成层、次生木质部、初生木质部。在根中五叶木通木质部导管口径比三叶木通的大很多。

This system simulated in vivo the processes of cambium occurrence, cell differentiation and xylogenesis.

参照杜仲的剥皮再生经验建立了毛白杨的剥皮再生系统，该过程基本模拟了自然条件下形成层发生、细胞分化及木质部形成的过程。

The results of anatomical observation indicated that the graft compatibility is better when the internal structure of scion and rootstock ( the size of cambium cell, xylem/ phloem and area of vascular) is similar;

另外，解剖结构观察发现，砧木与接穗一年生茎的形成层细胞大小、木韧比（木质部/韧皮部）及导管面积越相近，两者的亲和性越好。

The cells from the division transformed into cambium cell groups ( root initials);

转变为分生组织细胞群（即根原始细胞）；

The present results indicated the remarkable impact of salt stress on cambium cell activity and secondary xylem cell differentiation of both root and stem.

显微结构观测表明，盐胁迫对根和茎形成层细胞的活动和次生韧皮部和木质部细胞的分化产生显著影响。

It was analysed that the phenomenon was related to the divide and differentiate of vascular cambium cell.

分析此现象可能与维管形成层细胞的分裂分化作用有关。

The starch of hard species disappeared completely, content of sugar were high fat and lipids were concentrated cambium layer.

其中，抗寒种类淀粉粒小且水解彻底，还原糖含量高，脂类物质在形成层处高度聚集。

Four weeks after operation, the newborn trabecular in the group of the cambium layer facing toward the bone was more than the other two groups.

4周生发层朝向骨组，新生骨小梁较另外两组显著增多。

I raise the possibility of rhabdomyosarcoma with characteristic cambium layer under normal epithelia and possible "strap" cells.

肉瘤成分可能是横纹肌肉瘤，因为正常上皮下方见到特征性的生发层和可疑“带状细胞”。

Intrafascicular cambium ( fascicular cambium) The part of the VASCULAR CAMBIUM within the vascular between the xylem and phloem.

束中形成层：是位于木质部和韧皮部构成的维管束内的一部分维管形成层。

The primary xylem of root is diarch, of which developmental process contains primary growth and secondary growth. Secondary growth mainly depends on the activity of the vascular cambium and cork cambium.

其根为二原型，发育过程可分为初生生长和次生生长，成熟根的结构以次生结构为主，次生生长主要依靠维管形成层和木栓形成层的活动来完成。

However, before forming the cork cambium, pericyclic cells produced many layers pericyclic parenchyma cells by periclinal division.

但中柱鞘细胞在形成木栓形成层前，先进行平周分裂，形成了由多层细胞组成的中柱鞘细胞环。

About 15 days after girdling, a cork cambium developed near the surface of callus, then developed normal periderm rapidly.

大约15天左右在愈伤组织近表面细胞中发生木栓形成层，以后迅速形成正常的周皮。

The cork cambium originated from pericyclic cells that resumed their dividing capabilities.

其木栓形成层由中柱鞘细胞恢复分裂能力而形成。

Active rule of cork cambium is different in different trees, so form the many types of bark.

由于木栓形成层活动的规律不同，所以出现有各种各样的树皮。

The secondary growth mainly relied on activities of vascular cambium and cork cambium.

次生生长主要是依靠维管形成层和木栓形成层的活动来完成。

Meanwhile, paraffin-cut section method was used for studying on callus formation, cork cambium and vascular cambium initiation.

同时，运用石蜡切片法研究剥皮后愈伤组织的形成、木栓形成层和维管形成层的发生；

With the progressive development of stem, the activity of vascular cambium began. The fascicular cambium differentiated into secondary xylem and secondary phloem, while the interfascicular cambium only differentiated into wide ray of parenchyma tissue.

随着茎的继续发育，维管形成层开始活动，由束中形成层产生次生韧皮部和次生木质部分子；而束间形成层仅产生薄壁细胞组成宽的射线。