动物造模 z-bo 2020-08-10 576

　　(1) Reproduction method The mini-pigs were fasted for 12 hours before the experiment. After anesthetized by intraperitoneal injection of 50g/L thiopental sodium at a dose of 0.7ml/kg body weight, the back was shaved, with an area of 40cm×25cm. After the water temperature (100°C) of the super thermostat is constant, lightly press the scald probe (copper, round, diameter 18cm, area 2.54cm2, the probe is connected to the super thermostat through a silicone tube wrapped in insulating material) on the back of the piglet Burn on the skin. The specific scald position is 2 cm away from each side of the spine, and the number of scalded planes is determined according to experimental needs.

　　(2) Model characteristics After scalding at different times, the wound surface is round with the same shape as the scald probe, and the area is the same. The edges are neat and the boundary between the burned area and the surrounding tissues is clear. In general observation, the burn wound in the 5s group was reddish and whitish, and the wound was slightly higher than the surrounding normal skin; in the scald 10-20s group, the wound was white and dull, and the wound was slightly lower than the surrounding skin. Histological observation showed that in the burned 5s group, the epidermal cells above the spinous cell layer were degenerated and necrotic, and some spinous cells and all basal cells were normal; in the burned 10s group, full-thickness degeneration and necrosis of the epidermis, separation of epidermis and dermis, superficial dermal hyperemia and edema, collagen fibers Mild swelling and degeneration, infiltration of inflammatory leukocytes; 15s burn group, epidermis and superficial dermis coagulation and necrosis, dermal collagen fibers are mildly swollen and degenerated, and they are red, causing strips, partial damage to the skin appendages of the superficial dermis, and deep skin The attachment is intact, showing histopathological changes similar to deep second-degree burns.

　　(3) Comparative medicine This method can prepare small-area scald wounds with consistent area and depth on the skin of miniature pigs. Compared with the conventionally used boiling water immersion scald and aluminum rod scald method, the biggest advantage of this method is that the edge of the planed surface is neat and clear from the normal tissue. However, it is difficult to make a standard small-area scald wound with the boiling water immersion method. It is often easy to cause non-injury tissue damage, and its burned area is not easy to control. Apply this method to burn for 5-20s. With the extension of the burn time, the skin damage gradually increases, and the depth of the damage can reach the epidermis, superficial and deep dermis respectively. A scald can reach deep second-degree scald within 15s, which is suitable for the healing process of scald wound and the experimental study of topical medicine on scald wound healing.