The developmental process of fibers could be divided into three continual stages such as fiber initial formation and the formation of primary wall and secondary wall.

纤维细胞的发育过程可以分成明显的三个连续阶段：纤维原始细胞形成期、初生壁形成期和次生壁形成期。

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TEM images showed that cell wall of the fibre is typically divided into three layers including the primary wall (p), the middle lamellar (ML) and the secondary wall (S1, S2 and S3).

纤维细胞壁的超微结构典型地分为胞间层(ML)、初生壁(P)、次生壁外层(S1)、次生壁中层(S2)及次生壁内层(S3)。

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Among primary Wall Street competitors Morgan Stanley, Bank of America, Citigroup and JPMorgan, only Goldman Sachs is a net buyer of shares.

FORBES: Goldman Sachs Floats On Buffett Moat

The Treasury can auction its own bonds without need to pass them through privately owned primary dealers on Wall Street to get them sold.

FORBES: Connect

Washington's primary role doesn't excuse Wall Street's excesses, but it puts them in proper perspective.

FORBES: Magazine Article