Objective To investigate neural correlates of the retrieval of temporal order.Methods ERP of 19 channels was recorded from 17 healthy young students while they performed a recency judgment task,a recognition task and a visual discrimination task separately,which were based on Sternberg paradigm.One-way ANOVA of repeated-measurement and post-hoc paired comparisons were carried out for both the task factor(temporal order,recognition and control)and the temporal distance factor correspondingly.The latter contains 3 intervals (1,2 and 3)between the targets.Results The temporal distance effect was significant:the closer targets correspond to longer reaction time((745.5±106.1)ms,(711.7±102.2)ms,(653.7±81.5)ms;F_((1.28,20.48))=43.37,P=0.00]and higher error rate((62.8±7.0)%,(72.5±5.4)%,(84.5±6.4)%;F_((1.32,21.11))=135.99,P=0.00].Significant behavioral effect of the task factor was also found for both reaction time(F_((1.32,21.11))=135.99,P=0.00)and error rate(F_((2,32))=200.31,P=0.00).No significant behavioral difference was found between the temporal order group and the recognition group.The spatiotemporal pattern of statistical parametric mapping(SPM)suggested the ERP effects of temporal order were presented in left temporal region (260～270 ms),bilateral parietal-occipital areas(280～290 ms),and bilateral parietal lobes(300～400 ms)prominently.No ERP effect was found between the temporal order task and the recognition task.Conclusions The neural correlates of the temporal distance effect exist in bilateral parietal regions.Temporal order as well as object information processing involves similar cerebral regions during the retrieval period.

Objective To explore the relationship between bronchoalveolar lavage fluid (BALF) Mycoplasma load and clinical characteristics in children with Mycoplasma pneumoniae (MP) pneumonia.Methods MP DNA was quantitatively detected by fluorescent real-time PCR in BALF from 67 children with MP pneumonia.They were classified into three groups:low MP load group (＜ 103/ml,21 cases),moderate MP load group (103-106/ml,22 cases) and high MP load group (＞ 106/ml,24 cases).Clinical symptom,main laboratory and imaging results of children among three groups were compared.Results When compared with low MP load group and moderate MP load group,high MP load group had longer fever duration [(7.4 ± 2.6),(10.0 ± 2.4) d vs.(12.4 ± 2.7) d],longer time to normalization of temperature with macrolide administration [(4.2 ± 1.0),(8.5 ± 2.4) d vs.(10.8 ± 4.4) d],more patients with high fever,there was significant difference (P ＜ 0.05).Statistically significant difference existed in C-reactive protein among three groups [(3.0 ± 1.4),(11.5 ±7.6),(34.0 ± 10.1) mg/L] (P =0.004).Large field of consolidation or atelectasis were found in 58.3％ (14/24) of high MP load group,much higher than 22.7％ (5/22) in moderate MP load group and 14.3％ (3/21) in low MP load group.Bilateral or massive pleural effusion was not found in low MP load group,while in moderate MP load and high MP load group,they were 13.6 ％ (3/22) and 25.0％ (6/24)(P =0.033).Conclusions There is a close relationship between MP load in BALF and clinical characteristics in children with MP pneumonia.Those with high MP load have a more severe process.

Objective To investigate neural correlates of the generation,execution and inhibition of motor intention. Methods Behavioral performance and event-related potentials (ERP) of 14 participants were recorded when they performed a two-staged Go-Nogo task. At the stage of intention preparation,three kinds of the "what" cues were presented separately to the participants : (1) to press a response key by the left or the right hand (the instructed) ,(2) to decide freely which hand will be used (the free) ,(3) to wait for the second cue (the control). At the stage of intention execution,the "whether" cue suggested the participants execute (Go) or withdraw (Nogo) the previous intention either voluntarily or forcedly. Results The interaction effect between the "what" and the "whether" was significant(F(2,26) = 8.262, P=0.002). The forced responses were faster than those of voluntary action under both the instructed condition ((468.52 ±105.87)ms vs (546.67 ±146.33)ms) and the control condition ((536.78 ± 83.28) ms vs (589.75 ± 140.80) ms). No significant difference was found for the free condition((538.71 ± 127. 39) ms vs (561. 44 ± 146. 51) ms). At the stage of intention preparation,significant ERP effects between the instructed intention and the freely intention were revealed in bilateral frontal regions (150～200 ms) , frontoparietal area (300～700 ms)and right temporal area. At the stage of intention execution,ERP effects between voluntary inhibition and voluntary action were observed in left prefrontal area (160～220 ms) ,fro-nto-cento-parietal area and right frontoparietal area. (300～550 ms). Conclusion The motor intention may be generated in the prefrontal area and maintained in the frontoparietal network. The left prefrontal and fronto-centro-parietal areas inhibit intention in the early stage and the right frontoparietal area involves response inhibition lately.

Objective Recent studies in neonatal animals have shown that even slightly decreasing in brain or core temperature could ameliorate the damage resulting from hypoxic-ischemia insults. But the influence of hypothermia which had been used after the end of hypoxia-ischemia of the model hypoxia-ischemia brain damage(HIBD)was unknown. This research wanted to investigate whether hypothermia of defferent begin time after HIBD still could protect the brain in neonatal rats. Methods Pericranial temperatures were adjusted to 31 C in neonatal rats immediately or 2h after the end of hypoxia-ischemia(HI),the number of apoptosis cells in HIBD rats' brain had been counted,rat pups' storing food ability had been observed. Results Apoptosis increased obviously when rat pups were 8 days old, while hypothermia reduced apoptosis ,and postponed apoptosis expression in group that 31 C hypothermia was used immediately or 1h after the end of HI,and hypothermia improved the rat pups' storing food ability. This effect was more obviously in the group that hypothermia was used immediately after the HI than in the group that hypothermia was used 1h after the HI. But the protective effect was not clear in the group that hypothermia was used 2 h after the HI. Conclusion Hypothermia which was used within 1h after the end of HI could protect the HIBD neonatal rat pups brain, this effect was more obviously in the hypothermia be used early after the end of HI group than in the hypothermia be used late after the end of HI group.

Objective To investigate the clinical efficiency of Huayu Xiaozhong Decoction (HXD) on preventing peri-operative deep venous thrombosis (DVT) in lower limbs following artificial total hip replacement. Methods Ninety cases following artificial total hip replacement were randomized into blank control group, Rivaroxaban group and HXD group, 30 cases in each group, and were treated with brown sugar water, Rivaroxaban, HXD respectively. Before operation, and one, 3 and 14 days after operation, we monitored the changes of bleeding volume, DVT incidence, hemoglobin, prothrombin time ( PT) , activated partial thromboplastin time ( APTT) , international normalized ratio (INR), and D-dimer (DD) in the three groups. Results (1) Fifteen cases had DVT, with a total incidence rate of 16.67%. Of the 15 cases, 10 were from blank control group, 2 from Rivaroxaban group, and 3 from HXD group. ( 2) The amount of bleeding volume of Rivaroxaban group was larger than that of the blank control group and HXD group (P<0.05), but the bleeding was mild. (3) One, 3 and 14 days after operation, PT and APTT were shortened in blank control group (P<0.01 compared with those before operation). PT, APTT and INR were prolonged, and coagulation function was improved in Rivaroxaban group and HXD group, the differences being significant as compared with the blank control group ( P<0.05). HXD group had better effect on improving INR than Rivaroxaban group ( P<0.05). ( 4) In the three groups, hemoglobin level began to decrease on postoperative day one, arrived to the bottom on postoperative day 3 (P<0.05), and rose up near to the normal level on postoperative day 14; HXD group had higher hemoglobin level than blank control group and Rivaroxaban group on postoperative day 3 and 14 ( P<0.05). The 3 groups had higher plasma DD level than the normal level before the operation, arrived to the highest level on postoperative day one and 3 ( P<0.05) , and fell down near to the normal level on postoperative day 14. The inter-group comparison results showed that Rivaroxaban group and HXD group had lower DD level than the blank control group on postoperative day 3 and 14 ( P<0.05). Conclusion HXD is effective on preventing DVT in the peri-operation period through reducing bleeding, increasing hemoglobin level and improving postoperative anemia. The efficiency and safety of HXD are similar to Rivaroxaban.

Objective To study the effects of tacrolimus(Tac) concentrations on the number of NK cells and receptor expression in peripheral blood of renal transplantation receptors.Methods A total of 60 first-time kidney transplantation recipients in our institute from Dec.2007 to July 2009 were followed up.Tac maintenance immunosuppressive therapy was given to all recipients.The recipients were divided into low-concentration Tac group (6.84 + 1.72μg/L,n =30) and highconcentration Tac group ( 11.88 + 2.59 μg/L,n =30) according to concentrations of Tac.Twenty healthy volunteers served as controls.Before and 6 months after operation,concentrations of Tac were analyzed by using micro particle immunoassay chemiluminescent method.NK cells and their receptors (CD85j,CD158d,CD94 and NKG2D) were detected by using flow cytometry.The concentrations of soluble HLA-G5 were detected by using ELISA.Results The number of NK cells in lowconcentration Tac group and high-concentration of Tac group preoperatively was significantly reduced as compared with control group (P ＜ 0.05 ). The percentage and number of NK cells in low concentration Tac group and high-concentration Tac group at 6th month after operation were significantly reduced as compared with control group (P＜0.05).The number of NK cells in lowconcentration Tac group was significantly greater than in high-concentration Tac group (P＜ 0.05).There was no significant differende in the expression of CD85j,CD158,CD94 and NKG2D before operation between two groups(P＞0.05).The expression of CD85j and CD158d in two groups was increased,but that of CD94 and NKG2D was decreased at 6th month post-transplantation as comapred with that preoperation.In low-concentration Tac group,the expression of CD85j and CD158d was increased as compared with that in high-concentration Tac group (P＜0.05 ).Spearman correlation analysis revealed that the CD85j and CD158d expression had a positive correlation with sHLA-G5(P＜0.01 ),but the NKG2D had a negative correlation with sHLA-G5(P＜0.01 ).Conclusion There was correlation between the concentrations of Tac and NK cells count and NK receptors. Low concentrations of Tac can safely and effectively protect kidney function.The number of NK cells andtheir inhibitor receptors are increased in the recipients with low concentration of Tac.

Objective To explore the value of diffusion tensor imaging (DTI)-metrics (fractional anisotropy, FA; mean diffusivity, MD; axial diffusivity, AD and radial diffusivity, RD) in assessing the neonatal neurobehavioral development. Methods From November 2010 to September 2017, 101 neonates (gestational age range, 30-42 weeks;male/female, 69/32) with no abnormalities on conventional MRI were retrospectively included. DTI scalar maps (FA, MD, AD and RD) were calculated by using FMRIB's diffusion toolbox. The tract-based spatial statistics (TBSS) was used to investigate the relationships between white matter (WM) DTI-metrics and neurobehavioral scores (i.e. behavioral and active tone). Automated fiber quantification (AFQ) was used to extract the CST (corticospinal tract), OR (optic radiation), AR (auditory radiation) and thal-PSC (thalamus-primary somatosensory cortex); Pearson correlation was further used to explore the relationships between neurobehavioral scores and DTI-metrics along the four tracts. Results TBSS results indicated that behavior scores showed significant correlations with DTI-metrics in almost the whole WM, e. g. corpus callosum, CST, OR, AR and etc (P<0.05, TFCE-FWE corrected). Significant correlations of active tone with MD, AD and RD were just observed in local WM regions, i. e. cerebral peduncle, anterior and posterior limb of internal capsule (P<0.05, TFCE-FWE corrected); while FA just showed boundary significant correlations in the above regions (P=0.055, TFCE-FWE corrected). AFQ results indicated that DTI-metrics along the almost entire CST, OR and thal-PSC showed significant correlations with behavior scores (P<0.05); while significant correlations mainly located in the initial and middle segments of AR (P<0.05). For active tone, significant correlations were only observed in the initial and middle segments of CST. Conclusions Neonatal brain WM DTI-metrics in specific sensorimotor regions, to a certain extent, could reflect the corresponding neurobehavior abilities, suggesting the potential value of DTI in assessing the neonatal neurodevelopment.

Objective To study the clinical manifestations,imaging features,treatment and outcome of umbilical venous catheters/peripherally inserted central venous catheters (UVC/PICC) associated pericardial effusion (PCE) and cardiac tamponade (CT) in neonates.Method Clinical data of cases with UVC/PICC associated PCE/CT that were found in neonatal intensive care unit of five hospitals in Shanxi province from January 2017 to December 2018 were extracted and retrospectively reviewed.Result In total,there were 632 cases received UVC/PICC insertions in 5 hospitals.7 cases of which were identified as PCE (1.0％) on echocardiography during the period of catheter indwelling,among which 5 cases suffered from PCE complicated CT (0.7％).7 cases with PCE included 6 premature infants and 1 full term infants with mean gestational age (32.6 ± 3.8) weeks and mean birth weight 1 550 (1 200,3 960) g.The mean age of PICC/UVC insertion was 14 h (1 ～ 19 h),the mean age of PCE/CT developed was 69 h (13 ～104 h) after insertion.The most common presentations included apnea/respiratory distress (7 cases),cyanosis/desaturation (7 cases),tachycardia (3 cases),bradycardia/asystole (5 cases).UVC/PICC tip ectopic was found in 6 cases after the symptoms of PCE emerged (4 cases at T6-T7 and 1 case at T12 vertebra level on chest X-ray,and 1 case at right atrium on echocardiogram).UVC/PICC tip was normal in 1 case (tip at T7-T8 vertebra level on chest X-ray).5 cases recovered after removal of catheter,pericardiocentesis and drainage of effusion;1 case recovered after removal of UVC without pericardiocentesis;1 case underwent pericardiocentesis,continued infusion for 5 h after extubated the UVC into inferior vena cava,then deceased.Conclusion UVC/PICC tip ectopic is the main cause of UVC/PICC associated PCE/CT.Immediate bedside echocardiography should be performed to any patient with UVC/PICC indwelling,who develops sudden unexplained apnea/respiratory distress,cyanosis,tachycardia/bradycardia/asystole.Timely removal of catheter and pericardiocentesis drainage may be life-saving.

Objective:To explore whether interactive learning mode can improve learning ability of medical students.Methods:From September 2017 to January 2018, there were 266 medical undergraduate interns of Grade 2014 in the department of pediatrics of the First Affiliated Hospital of Xi'an Jiaotong University. Interactive approach mode was used in pediatric probation teaching of hematological disease. And the questionnaire and final exam grade were used to evaluate the effect of interactive approach in pediatric clinical practice teaching and understand students' satisfaction with interactive learning. The test results were compared with those of 146 Grade 2013 students, who studied in the same period of 2016 and adopted traditional teaching methods. Data were analyzed using SPSS 19.0 software.Results:In the questionnaire survey, the interactive approach mode was believed to improve the learning enthusiasm by 95.8% (230/240) students, improve the ability of language expression by 97.5% (234/240) students, promote the knowledge understanding and memory by 93.3% (224/240) students, and enhance the ability of self-study and by 90.9% (218/240) students. Additionally, the mode was believed to facilitate the ability of analyzing and resolving problems by 94.2% (226/240) students, and enhance the ability of information technology, such as information retrieval ability, PPT production ability, by 96.2% (231/240) students. Moreover, the test results of students using interactive approach model mode were significantly higher than those using traditional teaching mode ( P<0.01). In the questionnaire survey, there were 92.5% (222/240) students accepting interactive approach mode. Conclusion:The teaching mode of interactive approach can improve the learning enthusiasm and learning ability of medical students, which is worthy of popularization and application in the probationary courses.

Objective:To study the relationship between white matter injury (WMI) and brain maturity in preterm infants at full-term corrected gestational age (cGA).Methods:A retrospective study was performed in preterm infants [GA≤32 weeks or birth weight (BW) ≤1 500 g] admitted to the neonatal intensive care unit of the First Affiliated Hospital of Xi'an Jiaotong University from January 2017 to August 2018 and the Northwest Women and Children's Hospital from January 2017 to June 2017. The infants received conventional magnetic resonance imaging (MRI) at cGA 37~42 weeks. The infants were assigned into the WMI group and the control group according to the WMI scoring system, including the total maturation scores (TMS) and four sub-item scores.Results:A total of 118 premature infants were enrolled in this study (17 cases in the WMI group and 101 cases in the control group). The GA was (30.3±1.7) weeks, and BW was (1 356±268) g. The proportion of delayed TMS in the WMI group was significantly higher than the control group [58.8%(10/17) vs. 31.7%(32/101), P<0.05]. The TMS of the WMI group were significantly lower than the control group [(10.7±1.8) vs. (11.8±1.5), P<0.05]. The sub-item scores of TMS showed that the myelination [(2.8±0.6) vs. (3.1±0.4), P<0.05] and glial cell migration bands of the WMI group [(1.6±0.4) vs. (2.1±0.6), P=0.004] were significantly lower than the control group and no significant differences existed in cortical folding and involution of germinal matrix tissue scores between the two groups. Conclusions:The brain maturity of preterm infants with WMI is substantially delayed than those without WMI, including delayed myelination and delayed disappearance of glial cell migration bands.