Research-oriented study is a comprehensive learning method focusing on the experimental process deriving from a main issue.Given our clinical teaching experience in years,we incorporated the research-oriented studies into the undergraduate Clinical Medicine course for grade 2009,integrating the trait of the clinical skills education and our local professional training objectives.In the studies,students selected their own topic,designed and did their experiments,searched for the information,processed and analyzed the experiment result and finally completed the thesis.Practice showed that after the strict implementation of research learning plan,students' learning interest,innovative thinking,practical skills,research ability and cooperation spirit all significantly enhanced.

Objective To discuss the application and effect evaluation of the standard operation procedure ( SOP ) teaching method during applying surgical practice teaching in local medical college . Method 123 undergraduate students from Grade 2011 clinical medical major in Medical College of Shaoguan University were selected as objects of study. The students were divided into test (odd) group and control (even) group by draw. The two groups were taught by the same teachers, while the SOP method was applied to the test group (n=62) and the traditional surgical clinical teaching method was applied to the control group (n=61). Meanwhile, we used a combined method of the formative assessment and final assess-ment to compare and analyze the teaching feedback. After their graduate internship, we compared their autonomous study capability, clinical evaluation thought, normativity of the operation and capability in their intern positions as well as the degree of satisfaction of the test of two groups by doing a survey among them. All these were analyzed by SPSS 18.0 software, and t test was used to compare two groups' measurement in-formation and count data with chi-square. Results The comprehensive evaluation scores of the test group were significantly higher than the control group, in which the margin was of statistical value [(79.394 ± 8.049) vs. (71.703±10.462), t=39.632, P=0.000]. The percentage of excellence of the test group was signif-icantly higher than the control group, in which the margin was of statistical value (59.68% vs. 39.35%, χ2=5.082, P=0.024). The percentage of failure of the test group was lower than the group taught by the tradi-tional method, in which the margin was of statistical value (3.22%vs. 16.39%, χ2=4.652, P=0.031). Its for-mative assessment result on the evaluation of the experimental teaching process and summative assessment scores were higher than the control group, and the difference was statistically significant [formative scores points: (46.018 ±5.749) vs. (42.771 ±6.459), t=19.445, P=0.000; summative scores: (33.659 ±3.437) vs. (29.063±4.366), t=36.249, P=0.000]. As far as their clinical graduate internship adaptation capabilities were concerned, students from the test group had more satisfaction on the teaching feedback over 4 perspectives than the other group, in which the margin was of statistical value. Experimental groups' satisfaction showed that: 93.55% of students thought the standard operation procedure (SOP) teaching method was beneficial to improving their clinical practice skills, 91.94%thought that it improved their surgical clinical work ability to adapt, 85.48% thought it helped to cultivate their surgical clinical thinking and innovation ability. Conclusions The SOP teaching method in surgical practice teaching helps to enhance students' clinical operation and adaptation capability and promote the teaching quality.

【Objective】 To determine the best collection time period of plasma which can be used for human COVID-19 immunoglobulin for intravenous injection through SARS-CoV-2-IgG change and neutralizing antibody distribution against different virus strain in representative mixed plasma before and after Omicron strain infection by ELISA and pseudovirus neutralization test. 【Methods】 An ELISA method for quantitative detection of SARS-CoV-2-IgG was established and its linear range,accuracy and precision was verified. SARS-CoV-2-IgG potency was detected in 25 convalescent plasma which were collected 20-40 days after confirmed Omicron infection, two groups of mixed plasma samples WP1 and WP2 were prepared according to the SARS-CoV-2-IgG results, and pseudovirus neutralization experiments with different virus strain (prototype strain, BA. 1,BA.2, BA.4/5, BF.7, BQ.1.1) were carried out to determine the distribution of neutralizing antibodies against different virus strain. SARS-CoV-2-IgG potency of representative mixed plasma collected from 14 plasma stations subordinate to the company before and after Omicron strain infection was detected, including Omicron convalescent plasma (OP) collected from different plasma stations from December 2022 to May 2023 and normal pool plasma (VN) feed in March 2023 which collected from March 2022 to December 2022. According to the results, the difference and the change rule with time of SARS-CoV-2-IgG before and after Omicron strain infection were analyzed. 【Results】 The linearity of SARS-CoV-2-IgG ranged from 6.25 to 200 EIU/mL, the accuracy in-batch ranged from 81.793% to 106.985%, the precision in-batch ranged from 1. 100% to 13.000%, and the total error in-batch ranged from 2.988% to 22.679%. The accuracy between batches ranged from 90.788%to 96.893%, the precision between batches ranged from 4.870% to 6.272%, and the total error between batches ranged from 9.192% to 15.399%. The results of pseudovirus neutralizing antibody showed that the potency of different virus strain neutralizing antibodies were in the order of prototype strain>BA.2>BA.4/5>BF.7≈ BQ.1.1>BA.1 and the correlation between WP1 and WP2 was high (Pearson r=0. 931 1, P=0.002 3) which indicated that the potency distribution of neutralizing antibodies of different virus strain in Omicron convalescent plasma was basically stable. Compared with the mixed convalescent plasma sample G128 collected in June 2022, the potency of Omicron neutralizing antibodies of WP series were significantly higher, the ratio of BA.2 antibody to prototype antibody increased from 26.9% (before infection) to 82.6%-87.5% (after infection). The results of VN series before Omicron infection were < 100 EIU/mL, and the results of OP series after Omicron infection showed that the plasma collected from the beginning of December 2022 was the peak of antibody in the same month,and then dropped sharply, entering a short plateau in February-March 2023 (potency was about 40% of the peak value),and then dropped sharply again in April (potency was about 20% of the peak value). 【Conclusion】 The potency and proportion of neutralizing antibody against Omicron subtype in convalescent plasma after COVID-19 Omicron strain infection increased significantly. IgG antibody of plasma donors in different regions reached its peak in the month of infection, then continued to dropped sharply. The best collection period of plasma that can be used for human COVID-19 immunoglobulin for intravenous injection was 1 to 2 months after infection.

【Objective】 To determine the ELISA kit for screening convalescence plasma with high potency of SARS-CoV-2 IgG by comparing and analyzing the plasma detection results of convalescent plasma collected in different periods via ELISA kits from two manufacturers and the results of mixed plasma with different potency via pseudovirus neutralization experiments. 【Methods】 Two ELISA kits from different manufacturers(named A, B) were used to detect the plasma of 269 convalescent patients collected from Feb.2020~Jan.2022. The correlation and concordance rate of the two results were analyzed to determine the kit preliminarily. According to the titers of diluted series of standard of the preliminary selected kit, 5 mixed plasma samples (G4-G128) with different potency were prepared. The correlation of ELISA IgG results of product A/B, as well as the pseudovirus neutralization test of the original strain, Omicron mutant BA.1 and BA.2 strains were analyzed. Combined with the outside-well dilution mode of the strongly positive samples, the kit for high potency of SARS-CoV-2 IgG screening was determined. 【Results】 When the internal control reference B2 was used as the standard, the detection sensitivity of product A and B was 1∶32 vs 1∶8; the detection sensitivity of product A was 4 times that of product B. The correlation Pearson r between the results given by two kits was 0.944 1(P<0.000 1). Product B with low sensitivity was primarily selected as an alternative kit. The ELISA IgG results of samples from mixed plasma showed that the order of correlation r between product A and B was 0.988. The correlation r between product A and neutralization antibody potency of the three viruses was original strain (0.978)>BA.2(0.970)>BA.1(0.799); the order of correlation r between ELISA IgG results of product B and neutralization antibody potency of the three viruses was original strain(0.994)>BA.2(0.968)>BA.1(0.804). If twice-diluted B2 was taken as the excellent standard, 55.4% of product B met the criterion, while 47.2% of product A met.For positive plasma with high IgG potency, the product B kit required a lower dilution of the sample, which was more convenient to operate. 【Conclusion】 Both of the ELISA IgG kit from product A and B can be used to screen IgG antibodies of SARS-CoV-2, while product B is more suitable for screening positive plasma with high IgG potency.