Objective To explore the mechanism of multi-medicine drug resistance in human ovarian cancer cell line COC1/5-Fu. Methods The apoptosis and the tolerance of COC1/5-Fu cell induced by 5-Fu were analyzed by FACS. The expression of apoptosis related genes, such as p53, bcl-2, bcl-xl and bax, in COCI/5-Fu cell line were analyzed by RT-PCR. Results The COC1/5-Fu cell has some de-gree of drug resistance to 5-Fu and several other commonly used kind of chemotherapy medicine, among of which, drug resistance of 5-Fu reach 107.0 times and Paclitaxel reach 9.0 times compared with COC1. When COC1 was treated with the concentration of 5-Fu (0μmo/L, 30μmo/L or 150 μmol/L), the AI was (6.5±1.0) %, (14.0±4.0) % and (20.0±5.0) %, respectively. The rate of apoptosis increased 1.2 time and 2.1 time, compared with not treated with 5-Fu, which were significantly different (P<0.05). But when COC1/5-Fu was treated with the same concentration of 5-Fu (30 μmo/L or 150 μmoL/L), the AI was (6.7±0.7)%, (7.1±2.2)% and (6.5±2.0)%. When treated with the same concentration of 5-Fu (30 μmo/L or 150 μmol/L) , the proportion of apoptosis was significantly increased, G0/G1 phase was increased, and S and G2/ M phases were reduced in COC1 cells, but the proportion of apoptosis and cell cycle was not changed in COC1/5-Fu cells. The expression of bcl-xl , bcl-xs and bax mRNA were significantly increased and the expression of p53 and cpp32 mRNA were significantly decreased in resistant COC1/5-Fu cells , compared with COC1 cells. Conclusion wtp53 gene mutation is related with cell cycle change of ovary cancer cell and drug resistance, which is one of multi- medicine drug resistance mechanisms of COC1/5-Fu.

Pulmonary blast injury has become the main type of trauma in modern warfare, characterized by externally mild injuries but internally severe injuries, rapid disease progression, and a high rate of early death. The injury is complicated in clinical practice, often with multiple and compound injuries. Currently, there is a lack of effective protective materials, accurate injury detection instrument and portable monitoring and transportation equipment, standardized clinical treatment guidelines in various medical centers, and evidence-based guidelines at home and abroad, resulting in a high mortality in clinlcal practice. Therefore, the Trauma Branch of Chinese Medical Association and the Editorial Committee of Chinese Journal of Trauma organized military and civilian experts in related fields such as thoracic surgery and traumatic surgery to jointly develop the Clinical treatment guideline for pulmonary blast injury ( version 2023) by combining evidence for effectiveness and clinical first-line treatment experience. This guideline provided 16 recommended opinions surrounding definition, characteristics, pre-hospital diagnosis and treatment, and in-hospital treatment of pulmonary blast injury, hoping to provide a basis for the clinical treatment in hospitals at different levels.