Objective To explore the role of remote ischemic preconditioning(RIPC)in prevention of contrast -induced nephropathy(CIN)in elderly patients undergoing coronary artery angiography(CAA).Methods 106 elderly patients were enrolled in this randomized control trial.According to random number table,the patients were randomized into control group (n =53)and RIPC group(n =53).All of the patients received 1 000mL of 0.9% sodium chloride injection before CAA.The RIPC group patients underwent RIPC in their right arms with sphygmomanometer cuff infla-tion for 5 minutes prior to the CAA,three cycles were repeated.Serum creatinine was detected before and 48 hours after CAA.Results CIN was reported in 10 cases in the control group and 3 cases in the RIPC group(χ2 =4.30, P =0.04).The levels of serum creatinine were increased[(96.38 ±9.50)μmol/L vs (88.87 ±10.24)μmol/L] after CAA in the control group(t =2.28,P =0.03),and there was no difference in the RIPC group(t =1.17,P =0.24).Conclusion RIPC has a protective effect on CIN in elderly patients in our study.Since this method is harm-less and cost effective,further studies is required to popularize PIPC to our clinical practice for prevention of CIN.

Objective To investigate visual impairment students' quality of life and its influencing factors in Braille learning class at Quanzhou Special School. Methods November, 2020, 52 students (aged seven to 26) with the best corrected distance visual acuity of the better eye above 0.02 were investigated with near visual acuity, contrast sensitivity and Chinese-version Low Vision Quality of Life Questionnaire (CLVQOL). The subjects were divided into second grade blindness group, first grade low vision group and second grade low vision group according to the best corrected distance visual acuity of the better eye. Results There were significant differences in distance visual acuity (Z = 45.671, P < 0.001), near visual acuity (Z = 24.972, P < 0.001), and contrast sensitivity (CS) ( Z = 13.285, P = 0.001) among three groups. There was a correlation between near visual acuity and distance visual acuity (r = 0.74, P < 0.001), CS to distance visual acuity (r = -0.58, P < 0.001) and near visual acuity (r = -0.57, P < 0.001), score of CLVQOL and CS (r = 0.44, P < 0.001). There were significant differences in the total score (Z = 10.145, P = 0.006), distance visual acuity subscale (Z = 13.586, P = 0.001), psychological adjustment subscale (Z = 7.824, P = 0.020), reading and fine work subscale (Z = 7.923, P = 0.019) of CLVQOL among the three groups. Conclusion Quality of life is different with the visual impairment for students in special school, especially the distance visual acuity, psychological adjustment and fine reading. CS correlates to the quality of life of visually impaired students, which needs to be a part of evaluation of visual function.