In order to understand the students'knowledge mastery,assess teaching effects and improve the quality of teaching,this article analyzed the test papers of Neurology among the five-year program clinical medicine students of Grade 2006 in our College.The results indicated that the mean score of the exam was 87.29 with a standard deviation of 7.90.The distribution was negatively skewed.The degree of difficulty was 0.78 and the discrimination is 0.19.The reliability was 0.59.It demonstrated that the test papers had a good reliability,the design of the test papers was too easy and could not reasonablely discriminate the degree in evaluating the students'mastery of the course.Therefore,we shoud pay attention to appropriate difficulty and ensare quality in preparing test papers to scientifically evaluate teaching quality.

Objective To evaluate the feasibility of the lateralization of unilateral medial temporal lobe epilepsy(mTLE)by using arterial-spin-labeling(ASL)based perfusion MR imaging and investigate the changes of perfusion in the regions related to mTLE network and the relationship between the perfusion and the clinical status.Methods Twenty-five patients with left-sided and 23 with right-sided mTLE were enroiled,and 30 healthy volunteers were recruited.The cerebral blood flow(CBF)of related region was measured based on pulsed-ASL sequence on Siemens 3 T scanner.The CBF of the mTLE group were compared with that in the controls by using ANOVA analysis.The asymmetric indices of CBF in the medial temporal lobe were calculated as the lesion side compared with the normal side in matched region in mTLE group.Results Compared with the volunteers,the patients with mTLE showed the decrease of CBF in the bilateral medial and lateral temporal,the frontal and parietal regions relating to the default-mode network and more serious in lesion side.The CBF values of the medial temporal lobe were negatively correlated with the epilepsy duration(r =-0.51,P ＜0.01).The asymmetric index of CBF as-0.01 has a 76.0％(19/25)sensitivity and a 78.3％(18/23)specificity to distinguish the lesion side.Conclusions The decrease of CBF in the temporal and extra-temporal region by ASL-based MRI suggests the functional abnormalities in the network involved by mTLE.The ASL technique is a useful tool for lateralizing the unilateral mTLE.

Objective: To explore the role of targeted ultrasound contrast agent in the evaluation of angiogenesis in papillary thyroid carcinoma (PTC) in nude mice by constructing platelet derived growth factor receptor α (PDGFRα)-targeted ultrasound contrast agents, and to explore the effect of platelet derived growth factor (PDGF) on angiogenesis in PTC. Methods: PDGFRα-targeted ultrasound contrast agents were constructed through biotin-avidin linkage, and blank micro-bubbles were served as control group. After the siRNA-PDGF BCPAP cell line was established, well prepared BCPAP cells or siRNA-PDGF-BCPAP cells were injected subcutaneously into the back of male BABL/C nude mice. The growth of the tumors was observed closely. All tumors of the normal group and the siRNA-PDGF group were examined by PDGFRα-targeted ultrasound contrast agents or blank micro-bubbles, and the dynamic images were analyzed quantitatively by QontraXt software.All mice were sacrificed after ultrasonography. Microvessels density (MVD) in the tumors was counted by CD31 staining and the expressions of vascular endothelial growth factor(VEGF) and PDGF were detected by Western Blot. Results: PTCs in nude mice were enhanced well by PDGFRα-targeted ultrasound contrast agent or blank micro-bubbles. The peak of tumors in siRNA-PDGF group was significantly lower than that in the normal group [(43.085±13.244)% vs (57.428±10.952)%, P=0.004]; MVD of the siRNA-PDGF group was significantly less than that of the normal group [(23.200±6.017)strips/view vs (35.000±8.456)strips/view, P=0.012]. The protein expression of PDGF and VEGF in siRNA-PDGF group were significantly lower than those in the normal group, respectively (0.142±0.058 vs 0.269±0.102, P=0.002; 0.096±0.036 vs 0.158±0.072, P=0.016). Conclusions PDGF plays an important role in angiogenesis of PTC, it maybe a new ultrasound molecular imaging method for monitoring tumor angiogenesis.