2.1 Model Preparation

2.1 Model Preparation

2.1.1 Abdominal Fluid Extraction

Three mice inoculated with the H22 tumor strain for 7 days were euthanized by cervical dislocation, fixed on a wax board, and after disinfecting the abdominal skin, the skin was cut open and removed. Using a high-temperature sterilized syringe, milky white abdominal fluid was aspirated and placed in a sterile container, then stored on ice. A small amount of abdominal fluid was also placed in a heparinized test tube for observing cell morphology and counting cells. The remaining abdominal fluid in the syringe was dropped onto a slide, smeared, stained with Wright's stain, and subjected to cell classification and counting; only when the proportion of cancer cells exceeded 97% could it be used [32].

2.1.2 Inoculation

① Draw 10 ml of normal saline into a triangular flask;

② Use a 5 ml syringe to draw 3 ml of abdominal fluid, immediately bring it into a clean bench, inject it into the 10 ml normal saline triangular flask, then add another 5 ml of normal saline (1:5 dilution), shake well, and adjust the cell count to 2 × 10⁷ cells/ml [33];

③ Take 3 ml of the above cell suspension into another triangular flask, then add 17 ml of normal saline to obtain the tumor cell suspension;

④ Randomly leave 10 mice un-inoculated as the normal control group, while the remaining 60 mice are inoculated with solid tumors;

⑤ Disinfect the right anterior axillary skin of the mice with a 75% alcohol cotton ball, and use a 1 ml syringe to subcutaneously inject 0.2 ml of the tumor cell suspension [32].