Objective To study the effect of nerve growth factor(NGF)in survival of super-length random flap.Methods The experiment employed the animal model of random flap in Wistar's rat back,applied 66.7 μg NGF locally in trial group's flap at the first day after operation with auto-control.The survival proportion,skin temperature and survival rate of random flap were observed,and the blood flow,the blood flow velocity,the blood flow volume change of random flap were measured by the laser and photic-conduct fiber means in differ time.Results The survival proportion(7.12±1.54)cm2 and survival rate(92±5)%of random flap of trial group was obviously higher(P＜0.05)than those in control group[(5.23±0.19)cm2,(69±5)%]after pedicle division.The blood flow,the blood flow velocity,the blood flow volume and skin temperature in the midge and at the end of random flap in the trial group were obviously higher than those in control group 1 day after operation(P＜0.05),and the blood flow velocity in the pedicle of random flap in the trial group was increased markedly(P＜0.05).The blood flow volume and skin temperature in the pedicle of random flap in the trial group were higher than those in control group 3 days after operation(P＜0.05).The survival of randomflapinthetrial groupwere very significantly increased than those in control group 7 days after operation(P＜0.01).Conclusion NGF can increase flap's blood flow,blood flow velocity and blood flow volume,enhancing survival of the big-proportioned and super-length random flap.

Objective To examine the chracteristics of distribution of the FGF R before and after the flap transplantation and the influence of exogenic bFGF on the distribution of FGF R. Method Caudally based random skin flaps were raised on the backs of Wistar rats,bFGF was instilled under flaps after closure.An immunohistochemical techniques stanining method was used. Results FGF receptors distributes in the stratum basal of epidermis,the vascular endothelial cells in the dermis and hypodermis,the fibroblasts and the epithelial cells of the hair follicle and the sweat gland.In compared with preoperation,the quantity of increased gradually from the 1st day to the fifth day after operation,and the peak value is on the fifth day,it then recovered to the pre operation level on the serventh day.After applying the exogenic bFGF,the positive immunoreactive cells in the experimental group,increased remarkably from the Ist day to the 3rd day after operation in contrast with the control group.The peak value is on the 3rd day which was two days earlier than that of the control group and the peak value of the experimental group is remarkably higher than that of the control group.Conclusion\ FGF R distributes in the stratum basal of epidermis,the vascular endothelial cells in the dermis and hypodermis,the fibroblasts,and the epithelial cells of the hair follicle and the sweat gland.In compaired with pre operation,the quantity of the positive immunoreactive cells of FGF R were increased gradually from the Ist day to fifth day after operation,and the peak value is on the fifth day.After applying the exogenic bFGF,the positive immunoreactive cells of FGF receptors were increased.\;[