【每周一问】2023.12.25-关于毛囊组织病理切片（第2问）

王帆

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请为以下6张不同毛囊周期的毛囊的病理组织切片照片，找到对应的文字描述？

1：静止期毛囊--c

2：无毛静止期毛囊--f

3：生长期早期毛囊--d

4：生长期晚期毛囊--a

5：中间期毛囊--b

6：生长期早期的较晚阶段毛囊--e

答案：1-c；2-f；3-d；4-a；5-b；6-e

答案解析：

(a)生长期晚期HF，有发育完全的下段和峡部。

(b)中间期HF。下段因有丝分裂活动的停止和细胞凋亡(星号)而消退，并在峡部末端开始形成由毛膜角蛋白包围的棒状毛。真皮乳头(星状)改变其形状并保持与退化的上皮带连接。位于真皮乳头下方连接的结缔组织鞘，图像中不可见。

(c)静止期HF，其特征是发育完全的棒状毛和位于靠近棒状毛周围的外根鞘的真皮乳头(星状)。峡部和下段的内根鞘在静止期HF中不存在。外根鞘和真皮乳头之间的小细胞层代表下一代毛胚。

(d)生长期早期。下一代毛胚细胞(黑边白箭，末端呈锯齿状)开始向下增殖形成下段。

(e)生长期早期的较晚阶段。注意细长的外根鞘上皮带和箭指的有丝分裂图。

(f)无毛静止期HF。毛膜角蛋白附着在外根鞘，但在毛囊腔内没有HS。

HF：毛囊；HS：毛干

(a) Late anagen HF with a fully developed inferior segment and the isthmus.

(b) Catagen HF. The inferior segment regresses by cessation of the mitotic activity and by apoptosis (indicated by asterisk) and the club hair surrounded by trichilemmal keratin forms starting at the proximal end of the isthmus. The dermal papilla (star) changes its shape and remains attached to the regressing epithelial strand. The trailing connective tissue sheath, which is located below the dermal papilla, is not visible in this image.

(c) Telogen HF characterized by a fully developed club hair and a dermal papilla (star) that is located close to the outer root sheath surrounding the club hair. The inner root sheath of the isthmus and the inferior segment is not present in the telogen HF. The small cell layer between the outer root sheath and the dermal papilla represents the secondary hair germ.

(d) Early anagen stage. The cells of the secondary hair germ (white arrow with an indented end and surrounded in black) start to proliferate downward to form the inferior segment.

(e) Early anagen at a later stage. Note the elongated epithelial strand of the outer root sheath and the mitotic figure indicated by an arrow.

(f) Kenogen HF. Trichilemmal keratin is anchored to the outer root sheath, but a HS is missing in the follicular lumen.

Urumqi冬

1b、2e、3f、4a、5d、6c

潘潘小pig

1C 2D 3E 4B 5A 6F