Objective To explore the influence of the scores and weights of the regular grade on the evaluation of students' learning effect.Method To compare the impact of the regular grade before and after adjustment on the total mark,analyze the problems exposed during scoring and search for the solutions according to Medical Microbiology results of four grades including Grade 2010 to 2013.SPSS 13.0 software was used for statistical analysis and Pearson method was used for correlation analysis and theory achievement scores.Results The regular grade of four grades scored highly,with the average (95.00 ± 3.80),(96.00 ± 4.55),(95.00 ± 2.84) and (95.00 ±-2.82) respectively.What was more,it had randomness.The correlation coefficient between regular grade and total mark were 0.069,0.149,0.984 and 0.285 respectively.The regular grade of Grade 2010 was the same as Grade 2013 and the theoretical score of Grade 2013 was 4 points lower than Grade 2010(71 vs.75),however the total mark of Grade 2013 was 1 point higher than Grade 2010 (80 vs.79),which showed the more the regular grade weights,the greater it impacted on the total mark.Conclusion The appropriate score and weight of the regular grade is important to evaluate the students' learning effect objectively.

Objective To investigate the diagnosis and treatment of ectopic para-aortic pheochromocytoma. Methods Clinical data of 2 cases with ectopic para-aortic pheochromocytoma in the Third Affiliated Hospital of Sun Yat-sen University from August 2012 to December 2013 were analyzed retrospectively. The informed consents of both patients were obtained and local ethical committee approval had been received. Both patients were female with the age of 54, 57 years old. The occurrence of disease, diagnosis, treatments and efficacy were observed. Results Case 1 was admitted in hospital for complaint of 1-month distending pain in upper abdominal and ifnding of retroperitoneal space-occupying lesion for 8 d. Solid space-occupying lesion at the right side of mid-upper abdomen was found by abdominal ultrasound and computer tomography (CT) examination. The preoperative diagnosis was abdominal mesenchymoma. Case 2 was admitted in hospital for complaint of palpitation, chest pain and ifnding of hepatic space-occupying lesion for 10 d and had a history of 5-year hypertension. Cystic solid space-occupying lesion in the hepatic caudate lobe was found by abdominal ultrasound, CT and magnetic resonance imaging (MRI) examinations and cystadenoma was suspected. The 2 patients underwent resection of ectopic para-aortic pheochromocytoma under general anesthesia by tracheal intubation. The intraoperative exploration found that touching the tumor had great impacts on blood pressure and heart rate and ectopic para-aortic pheochromocytoma was diagnosed. The patients were transferred to surgical intensive care unit (ICU) for monitoring and treatment. Pheochromocytoma was confirmed by the pathological examination. The patients were recovered and discharged from hospital and remained well till the paper submission date. Conclusions Ectopic para-aortic pheochromocytoma is a rare disease without characteristic clinical features. It is dififcult for preoperative diagnosis. The conifrmation is mainly depends on the pathological ifndings. Surgical resection is the priority of treatment. Fully assessment of operative risk before operation, avoiding touching tumor tissues during operation, complete excision of tumor capsule, close monitoring on the blood pressure after operation can achieve a good clinical treatment outcome.

Objective To investigate the effect and mechanism of liver cancer derived mesenchymal stem cell (LCMSC) on the invasion of liver cancer cells. Methods The expressions of interleukin (IL)-6, IL-8 and chemotactic factors CXCL1, CXCL5 and CXCL12 mRNA in the bone marrow derived mesenchymal stem cell (BMSC) and LCMSC were detected by reverse transcription-polymerase chain reaction (RT-PCR). The expression of protein CXCL12 in the supernate of LCMSC was detected by enzyme-linked immunosorbent assy (ELISA) and Western blot. Different cells were co-cultured and divided into the HepG2+BMSC, HepG2+LCMSC and HepG2+LCMSC+siRNA-CXCL12 groups. The effect of CXCL12 on the invasion of liver cancer HepG2 cells were detected by Transwell migration assay. The experiment data were compared using one way analysis of variance and LSD-t test or t test. Results The expression of CXCL12 mRNA in LCMSC was 60.3±2.4, significantly higher than 13.8±1.8 in BMSC (t=15.68, P<0.05). The expression of protein CXCL12 in the supernate of LCMSC was (31.5±1.7) ng/L, significantly higher than (14.3±1.5) ng/L in BMSC (t=7.60, P<0.05). And the expression of protein CXCL12 was up-regulated. Transwell migration assay indicated that the quantity of membrane-invasion cells in the HepG2+LCMSC group was 110±12, significantly higher than 65±9 in the HepG2+BMSC group and 76±7 in the HepG2+LCMSC+siRNA-CXCL12 group (LSD-t=5.25, 4.86; P<0.05). Conclusion CXCL12 is highly expressed in LCMSC. LCMSC may enhance the invasion of HepG2 cells through up-regulating the expression of CXCL12. The invasion of liver cancer cells can be effectively weakend by silencing the CXCL12 gene with siRNA.