1、细胞的生长和调控纤维母细胞纤维细胞原始间叶细胞转化为纤维母细胞产生胶原纤维并转化为纤维细胞模式图 原始间叶细胞 毛细血管再生模式图1.基底膜分解，内皮细胞肥大、增生，形成幼芽2.内皮细胞向前移动，其后的内皮细胞分裂增生，靠近血管处的内皮细胞先分化成熟，并有新的基底膜形成正常神经纤维神经纤维断离，远端及近端的一部分髓鞘及轴突崩解神经纤维再生模式图 神经膜细胞增生，轴突生长 神经轴突达末梢，多余部分消失 神经纤维再生模式图 肉芽组织镜下结构模式图 大量由内皮细胞增生形成的实性细胞索及扩张的毛细血管，向创面垂直生长，并以小动脉为轴心，在周围形成袢状弯曲的毛细血管网。毛细血管周围有许多新生的纤维母细胞
2、。常有大量渗出液及炎性细胞。炎性细胞常以巨噬细胞为主，也有多少不等的中性粒细胞及淋巴细胞。图注：新生的毛细血管呈出芽状互相联络，内皮细胞肿胀。纤维母细胞增生（f），并可见嗜中及嗜酸性粒细胞浸润，浆细胞浸润。肌纤维母细胞：核胖、核仁明显 图注：右手烫伤累及组织较深，坏死组织脱落后由肉芽组织增生取代，最后成为瘢痕组织。瘢痕组织较硬，缺乏弹性，由于瘢痕的挛缩，皮肤成皱缩状。fibrin-clotted blooddehydration of surface scabneutrophilsDay 1:neutrophils migrate from the incision margin toward
3、 the fibrin clot.basal cells at the cut edge of the epidermis undergo mitosis.within 24-48 h,epithelial cells from both edges have begun to migrate and proliferate along the dermis,depositing basement membrane components as they progress.The cells meet in the midline beneath the surface scab,yieldin
4、g a thin but continuous epithelial layer.24 hours3-7 daysDays 2-3:neutrophils have been largely replaced by macrophagesgranulation tissue progressively invades the incision spacecollagen fibers develop at the incision marginsepithelial cell proliferation continues,yielding a thickened epidermal cove
5、ring layerDays 4-5:neovascularization reaches its peak as granulation tissue fills the incision collagen fibrils become more abundant and begin to bridge the incision.the epidermis recovers its normal thickness,yielding a mature epidermal architecture with surface keratinizationSecond week:continued
6、 collagen accumulation and fibroblast proliferation leukocyte infiltrate,edema,and increased vascularity are substantially diminishedFirst month:the unconspicuous scar comprises a cellular connective tissue largely devoid of inflammatory cells and covered by an essentially normal epidermis.1创缘整齐，组织破坏少 2经缝合，创缘对合，炎症反应轻 3表皮再生，少量肉芽组织从伤口缘长入4愈合后少量疤痕形成创伤一期愈合模式图创伤二期愈合模式图1创口大，创缘不整，组织破坏多2伤口收缩，炎症反应重3.肉芽组织从伤口底部及边缘将伤口填平，然后表皮再生4.愈合后形成疤痕大24hours3-7 daysweeks
