Objective To investigate the characteristics and neural mechanisms of visual attention dysfunction in patients with hypertension using the event related potentials(ERPs).Methods Visual Oddball pattern was adopted to analyze P3a and P3b components of 15 essential hypertensives and 15 normotensives,and all the participants were submitted to cognitive assessment by Mini-Mental State Examination (MMSE).Results ①Novelty stimulus:the mean amplitude of N2 in hypertensive patients ((1.56± 1.15) μV) was decreased than normal controls ((-2.19±1.15) μV,P＜0.05),particularly at forehead-central sites (P＜0.05).In addition,the amplitude of P3a of hypertensive patients ((6.27± 1.01) μV) was different from normal controls ((7.09± 1.01) μV),but there was no statistical significance(P＞0.05).The latency of visual P3a was significantly longer in patients with hypertension group ((432.83 ± 8.22) ms) than that in control group ((403.10 ± 8.22) ms,P＞ 0.05).②Target stimulus:compared with control group ((6.75 ±0.90)μV),visual P3b amplitude in hypertension group ((4.08 ± 0.90) μV) was significantly declined (P＜ 0.05).Besides,the latency of visual P3b of hypertensive patients ((440.70 ± 6.42) ms) was different from normal controls ((436.91±6.42) ms),but there was no statistical significance(P＞0.05).③Compared with control group (27.31± 1.22),the M MSE score of patients with hypertension (24.55±2.42) was decreased (P＜0.05).The amplitude of visual P3b was positively correlated with MMSE scores in parietal region(r=0.51,P＜0.05).Conclusions The abilities of visual involuntary attention and voluntary attention are damaged in patients with hypertension,the impact degree of hypertension on two kinds of attention and the neural mechanisms are different.Moreover,there is a significant positive correlation between the amplitude of visual P3b and MMSE,which prompts that visual P3b for clinical early assessment of attention in patients with hypertension provides more objective neurophysiological basis.

Objective To investigate the role of contrast-enhanced ultrasound(CEUS) for detection of hepatic artery stenosis(HAS) in recipients following orthotopic liver transplantation(OLT). Methods CEUS was performed in 50 OLT recipients (42 men and 8 women) with abnormal liver function test and/or abnormal findings on color Doppler ultrasound(CDUS). Digital subtraction angiography (DSA), computed tomographic angiography(CTA) or follow-up CDUS was used as the reference standard. The degree (mild,narrowing rate＜50 %; moderate, narrowing rate 50 % ～ 75 %; severe, narrowing rate＞ 75 % ), location and type (single or multiple) of HAS were evaluated. Moderate and severe stenosis were defined as substantial stenosis. Results CTA or DSA depicted substantial HAS in 39 patients, 8 patients with mild HAS or normal HA were depicted on CTA,and the remaining 3 patients were diagnosed as non-substantial HAS on clinical and CDUS follow-up. CEUS depicted substantial HAS in 38 cases. Moreover,CEUS corrected falsepositive findings on CDUS in 9 of 50 cases(18.0% ). The accuracy, sensitivity, specificity, positive predictive value and negative predictive value of CEUS in diagnosing HAS were 90.0% ,92.3% ,81.8% ,94. 7% and 75.0%,respectively. Conclusions CEUS is able to provide comprehensive information including presence,degree,location and type of HAS, which may facilitate the further interventional procedure or surgical treatment.

Objective To determine the timing for therapy and efficacy for different types of hepatic artery stenosis (HAS) after orthotopic liver transplantation(OLT). Methods From October 2003 to May 2007, a total of 21 patients had hepatic artery stenosis after OLT in this hospital. Of the 21 patients, 19 underwent stent placement in their narrowed hepatic arteries and 2 were regularly followed up. Liver function, clinical outcomes, and the hepatic artery potency were reviewed. Results The occurring rate of HAS was 3.43% (21/613) and its median time of diagnosis was 146 days (range, 2-515 days). Six patients with early HAS were treated with interventions and 2 of them died.For the 4 surviving patients, 2 received retransplantation. For the 15 patients with late HAS, 13 were treated with interventions and 4 of them died. Two patients received retransplantation. Seven surviving patients had abnormality in liver function. Another 2 patients had normal liver function because of hepatic portal form compensatory circulation. Conclusion The presence of ischemic bile duct lesion and whether or not favourable compensatory circulation exists or not should be considered before individualized therapeutic regimens adopted according to postoperative HAS types.