Objective To obtain the acceptable range for posed smile characteristic index,in order to supply diagnostic and therapeutic basis for orthodontic treatment.Methods The 200 subjects included in the study consisted of 100 experienced orthodontists and 100 laypersons.Both two frontal posed smile photographs of man and woman were changed by several smile characteristic indexes,including the amount of incisor exposure,amount of gingival display,smile arc,buccal corridor fill,horizontal inclination of maxillary occlusal plate and distance from lower lip to maxillary incisor.All the subjects were desired to evaluate each images according to their own aesthetic standard.Results Each acceptable range for the amount of incisor exposure,amount of gingival display,smile arc,buccal corridor fill,horizontal inclination of maxillary occlusal plate and distance from lower lip to maxillary incisor,was 75 ％-100 ％ (male and female),0-2 mm (male) and 0-3 mm (female) ; 50 ％-100 ％(male and female) ; 0 ％-15 ％ (male) and 0 ％-20 ％ (female) ; 0-6° (male and female) ; 0 mm (male and female)(P＜0.05),respectively.And there was perception difference between the orthodontists and the laypersons on smile evaluation (P＜0.05).Conclusions Posed smile analysis should be an im portant aspect of orthodontic diagnosis and treatment planning.Orthodontists should not disturb con sonant smiles but create them with proper bracket positioning.

A total of 180 community medical staff in Jiangning District of Nanjing received continuous education in practical emergency medicine through theory teaching,practice and scene simulation once a year from 2011 to 2013.And the training outcomes were evaluated before and after training and the feedbacks of community medical staff collected each time.The assessment results of theory and practical skills after training in 2013 were better than before training in 2011 [theory:(61.72 ± 5.03) vs.(92.11 ± 5.56) points ; operation skills (55.28 ± 6.18) vs.(93.33 ± 3.45) points] (P ＜ 0.05).And the total satisfaction rate was 98.0％.

Traditional Tibetan medicine nature theory was the core of Tibetan medicine. This study was aimed to understand the scientific values of Tibetan medicine correctly and catch its unique advantages accurately. The history origin, nature and taste, target, effect, the relationship between diseases and Tibetan medicine and other aspects of traditional Tibetan medicine nature theory were discussed in this paper. Several points were put forward, which included the research of Tibetan medicine nature theory was the premise to maintain and develop Tibetan medicine; it was necessary to carry out literature research, definite and improve the nature theory; the data mining technology and systems biology should be applied to the theory research to elucidate the rules and scientific connotation of Tibetan medicine nature; building the model of experimental study with clinical research to determine its clinical values forward during the development of Tibetan medicine nature theory research.

Objective To explore the survival mechanism of hippocampal ne urons after damage of hypoxia-ischemia and reperfusion of brain.Methods Seven days old SD rats(n=56) were randomly divided into hypoxia-ischemia br a in iniury(HIBD) group and sham group.The HIBD and reperfusion model was establis hed.The flowing of blood was de tected by multicolor Doppler.The p-CREB(phosphorylated c-AMP response element bi nding protein)and c-Jun were immunohistochemically evaluated in hippocampus.Thi onin staining was used to observe the apoptosis.Results The expression of p-CREB reache d the peak at 3,24 h postreperfusion in the right hippocampus of HIBD group,and then decreased to the normal level on the 7th day.In contral group the same reg ions showed basic immn-noreactivity.While c-Jun reached the peak at 6 h postreperfusion,then with a slightly decrease at 24 h;and at 48 h the other peak appeared,then with a gradual decline .On the 7th day the mumber of positive cells were still significanthy more than control group(P0.05).The sham animal showed very few apoptosis cells in the regio ns of hippocampus.Conclusions The persistent activation of CREB in the hippocampus regulates,the expression of c-Jun through the signal transductions and is involved in the course of neuron s′ survival and repair during the period of post hypoxia-ischemia reperfusion.I t is very important for the protection of the pyramidal hippocampal neurons on t he damaged side,especially for the sensitive region CA1. J Appl Clin Pediatr,2005,20(2):133-135

Objective To assess the value of three-dimensional contrast-enhanced ultrasound (3D-CEUS) in evaluation origin of segment Ⅳ feeding artery in living liver donors. Methods 3D-CEUS were used to examine 20 living liver donors. The origin of segment Ⅳ feeding artery were evaluated by two radiologists who blinded to other imaging information. The findings obtained on operation and (or) CTA were used as the reference standard. Results Segment Ⅳ feeding artery originating from left artery, both left and right artery, proper hepatic artery were demonstrated on 3D-CEUS in 13, 1 and 2 patients,respectively. 3D-CEUS accurately depicted the origin of segment Ⅳ feeding artery in 16(80%) patiens.Conclusions 3D-CEUS could be a useful method to demonstrate the origin of segment Ⅳ feeding artery in preoperative evaluation for LDLT.

Objective To assess the value of three-dimensional contrast-enhanced ultrasonography (3D-CEUS) in evaluation of hepatic arteries variants.Methods Both two-dimensional contrast-enhanced ultrasonography (2D-CEUS) and 3D-CEUS were used to assess 30 patients including living donor candidates and patients with upper abdomen tumors.The reference standard was operation or CTA or DSA or MRA,and the accuracy for detecting hepatic artery variants provided by the two methods was evaluated.Arterial anatomic types were defined by using Michels classification.Results The total accuracy for detecting hepatic artery anatomy types by 2D-CEUS was 40.0% (12/30),while 83.3% (25/30) by 2D-CEUS.For convention anatomy types the accuracy on 2D-CEUS and 3D-CEUS were 40.9%(9/22)and 90.9%(20/22),respectively.The difference was statistically significant (P<0.05).For anatomy variants types the accuracy on 2D-CEUS and 3D-CEUS were 37.5%(3/8)and 62.5%(5/8),respectively.No significant difference between these two methods was observed.Conclusion 3D-CEUS was a new method in diagnosis of hepatic arteries anatomy types with practical clinical value in evaluation of the living liver donors.

Objective To investigate the feasibility and methodology of detecting the microcirculation of hilar bile duct wall with contrast-enhanced ultrasound (CEUS). Methods Sixteen patients after orthotropic liver transplantation(OLT) were studied. The dosage of contrast agent(SonoVue) was set for 2 groups: 1.5 ml and 2.4 ml. Each group was composed of 8 patients. The imaging quality of CEUS were retrospectively analyzed and divided into 3 grades: good, ordinary and bad. There were 2 patients received retransplantation. Their morphologic features of hilar bile duct wall in baseline ultrasound (US) and CEUS were compared with those in pathological examination. Results Biliary perfusion could be displayed by CEUS continuously,real-timely and clearly. The imaging quality was good in 8 cases(50%), ordinary in 6 cases (37. 5%) and bad in 2 cases(12. 5%). There was no significant difference between the imaging quality of 1. 5 ml and that of 2. 4 ml group ( P = 0. 78). Conclusions The imaging quality of hilar bile duct wall in CEUS is good enough to detect its microcirculation. There is no significant difference between the imaging quality of 1. 5 ml and that of 2.4 ml group.

Objective To investigate the diagnostic value of MRI in the infantile developmental dislocation of the hip.Methods Forty-five cases of preoperative hip MRI data of DDH (patient group)and 40 cases of normal hip (control group)MRI data were retrospectively analyzed.Three types were classified according to the standard of Dunn.Then the bony acetabular index (BAI),cartilaginous acetabular index (CAI)were measured on coronal MRI and all the intra-articular structures (articular cartilage,labrum, teres ligament and iliopsoas)in the acetabulum that impeded the reduction of the femoral head were observed.Results There were normal hips (80 hips)and dislocated hips (73 hips).In dislocated hips typeⅠ (30 hips),typeⅡ (20 hips),and typeⅢ (23 hips) were found.The values of BAI were (26.13±2.19)°and (35.87±4.42)°,CAI (13.84±1.07)°and (21.92±4.70)°for patient group and control group.The values of BAI were (31.80±1.74)°,(37.80±3.40)°and (39.17±4.11)°,CAI (17.20±2.68)°,(20.91±2.02)°and (27.50±2.78)°for the typesⅠ,Ⅱ,Ⅲ respectively.Differences of BAI and CAI between patient group and control group were showed (t=-11.048 and -9.188,P =0.000).Statistically significants were found among the typeⅠ,Ⅱ,Ⅲ(F=22.159 and 47.241,P =0.000).There were linear correlations for patient group ,control group,and the typeⅠ,Ⅱ,Ⅲ (r= 0.964,0.844,0.953,0.931 and 0.870,P =0.000).Some pathological changes such as varus labrum,thick teres ligament,iliopsoas spasm,articular cartilage hyperplasia,fat hyperplasia,joint effusion were observed in the type Ⅱand Ⅲ.Conclusion MRI is not only used for measuring the values of BAI and CAI,and a linear correlation among all kinds of DDH,but also some factors hindering the reduction of the femoral head can be found clearly.It can provide an important reference basis for the diagnosis and treatment of DDH.

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 study the whole genome DNA methylation changes induced by low dose radiation (LDR) in mouse,and mRNA expression profiles of DNMT1 and MBD2 in peripheral blood mononuclear cell (PBMC) and tissues.Methods Thirty male BALB/c mice were randomly divided into 3 groups:control,single exposure (0.5 Gy),and fractionated exposure of 6 MV X-rays for 10 d (0.05 Gy/d × 10 d).Control mice were sham-treated.To determine the immediate (early) effect of irradiation,15 mice (5/group) were sacrificed 2 h after the last irradiation.The other 15 mice were sacrificed 1 month after the last irradiation (delayed effect).Before sacrifice,blood was sampled immediately.Kidney,liver,spleen,brain and lung tissues were collected.A global DNA methylation quantification Kit and highperformance liquid chromatography (HPLC) were used to investigate the methylation level in blood DNA.The expressions of DNMT1 and MBD2 were determined by RT-PCR.Results For the early effects of irradiation,as compared with controls,fractionated exposure to X-ray irradiation led to the significant depression of global DNA methylation level in blood (t =10.19 and 8.93,P ＜ 0.05).DNMT1 and MBD2 mRNA were down-regulated in PBMC,kidney and liver (t =5.06,3.01,3.97,12.25,3.50 and 3.73,P ＜0.05),and MBD2 was also down-regulated in spleen (t =3.03,P ＜ 0.05).However,no changes were observed in single exposed group.As for the delayed effects,the methylation levels of blood were not changed in the single or fractionated exposed groups,and only MBD2 mRNA was down-regulated in PBMC and brain of fractionated exposed group (t =3.52 and 2.85,P ＜ 0.05).Conclusions Fractionated LDR exposure can induce genome DNA hypomethylation,which is tissue-specific,and may be related with down-regulation of DNMT1 and MBD2.