“…The 42 studies were evaluated according to the study quality evaluation index of preclinical research, and the average score of 6.52 is shown in Table 4 . The overall score of the researches ranged 3~9, among which 23 studies scored higher than 7 ( 8 – 10 , 15 , 16 , 19 , 21 , 22 , 24 – 26 , 28 , 29 , 32 – 34 , 38 , 44 – 46 , 48 – 50 ), and 19 studies scored between 3~6 ( 7 , 14 , 17 , 18 , 20 , 23 , 27 , 30 , 31 , 35 – 37 , 39 – 43 , 47 , 51 ). The main factors causing the subtraction of the research were lack of description of temperature, types of narcotic drugs, and randomization information.…”