[Retracted] Surgery and Postoperative Care of Patients Undergoing Percutaneous Nephrolithotomy under the Guidance of B-Ultrasound Based on Smart Internet of Things

Table 1

General information of patients.

Variable	Minimum	Max
Age	17	82
Creatinine before operation (μmmol/L)	17	1180
Stone size (mm)	4	65.7
Number of surgical channels	1	3
Operation time (min)	14	149
Antibiotic application days before surgery	1	16