Objective To evaluate the clinical effect of Wy 10 whitening combined with enamel microabrasion on bleaching dental fluorosis.Methods Forty patients with dental fluorosis were in-cluded and divided into two groups (20 each):group A was treated with Wy 10 whitening and enamel microabrasion,and group B only with Wy 10 whitening.Efficacy was measured according to the Vita classical shade guide before and after treatment.Sensitivity between groups was also tested.Results The effective rate of group A was significantly higher than that of group B (x2 =5.096,P＜0.05).The sensitive rates were 20.0％ (4/20) and 15.0％ (3/20) in group A and group B,respectively.No significant difference was found between the two groups in sensitivity (P＞0.05).Conclusions Wy 10 whitening combined with enamel microabrasion is an effective and safe method for bleaching dental fluorosis.

Objective To improve the understanding of malignant triton tumor on imaging findings.Methods CT and MRI findings of rare malignant triton tumor in 3 cases confirmed histologically were analysed with review of the literatures.Results 3 tumors included prostatic malignant triton tumor with pulmonary metastatic tumors and neurofibromatosis-I in 1 case,left haunch malignant triton tumor in 1 case and right maxillary sinus malignant triton tumor with destruction of maxillary sinus paries in 1 case.The imaging appearances of tumors were the huge soft tissue mass which strongly suggested malignant tumors,high signal intensity on T2WI,circular septa inside the tumors with low signal intensity.Conclusion Although the qualitative diagnosis of malignant triton tumor depends on pathological examination,CT and MRI play a useful role in diagnosis and differential diagnosis of this tumors.

Objective To prepare the Target-directed probe(Hab18-SPIO) and to test its phisichemical characteristics. Methods The McAb Target-directed probe(Hab18-SPIO) was prepared through hepatocellular carcinoma(HCC) McAb(Hab18) conjugated toSPIO using chemical method,while negative McAb probe(SED-SPIO) was also prepared using the same method.These agents weretested by high-performance liquid chromatography(HPLC) and electron microscope. Results The results of HPLC and electronmicroscope proved that Hab18 was conjugated SPIO effectively.The diameter of particles was between 50 and 70 nm.The binding rate of Hab18 was 97.5%. Conclusion The probe targeted to membrane-associated antigen of HCC(Hab18g) has been successfully prepared,which has novel physiochemical property.It is of great value in specific MR diagnosis of early HCCs.

OBJECTIVETo investigate the effect of different length and diameters on the stability of mini implant and to select optimal length and diameter using continuous variation of parameters.

METHODSTo perform 3-dimensional finite element analysis, finite element models of a maxilla, and mini implants with length of 6-12 mm and diameters of 1.2-2.0 mm were generated. Load of two different forces were applied to the head of mini implant. One type was horizontal force (HF), the other was composite force (CF). The maximum equivalent stress (Max EQV) in maxilla and the maximum displacement (Max DM) of mini implant were evaluated.

RESULTSThe Max EQV in maxilla and Max DM of mini implant decreased as length and diameter increased. When length was more than 9 mm, the evaluation indexes were small and had a less change. Datas indicated that diameter played a more important role in reducing target, and was a more effective parameter in reducing Max EQV when CF was loaded.

CONCLUSIONFrom biomechanical point of view, the choice of the length should not be more than 9 mm. When CF is loaded using the mini implant, diameter exceeding 1.2 mm are optimal design for mini implant.

Objective To study the effect of MMP-9 and ZO-1 expressions on the brain edema in rats with hepatic encepha -lopathy.Methods Ninety rats were randomly divided into two groups .In one group, rats were intraperitoneal of D -galactosamine (400mg/kg) with lipopolysaccharide(100μg/kg) to induce hepatic encephalopathy , and then observe the symptom.12 hours later, ammonia, the evans blue(EB)content, the brain water content and the MMP -9 mRNA and the ZO-1 mRNA in the brain tissue was as-sessed by real-time Q-PCR.Results Two hours later the rats in hepatic encephalopathy groups begin to appear the symptom .12 hours later, the ammonia, the EB content, the brain water content and the MMP -9 mRNA content of the hepatic encephalopathy groups was increased significantly[(279.53 ±9.78)μmol /L vs (33.85 ±1.50)μmol/L, (6.71 ±0.50)μg/g vs (3.96 ±0.48)μg/g, (82.14 ±0.30)% vs (76.07 ±0.39)% and 1.4255 ±0.1131 vs 0.8298 ±0.0537, P <0.01],but the ZO-1 mRNA content was decreased (1.0795 ±0.0534 vs 1.4576 ±0.0654, P <0.01).Conclusions Blood brain barrier permeability enhancement and brain edema in hepatic encephalopathy rats, MMP-9 mRNA increase and ZO-1 mRNA decrease may play an important role .

Objective To investigate the expression and clinical value of miRNA -22 in gastric cancer tissues.Methods Real -time PCR was used to detect the miRNA -22 expression in gastric cancer tissues and matched adjacent tissues.The correlations of miRNA -22 expression with clinic pathological features were analyzed. Results 87.5%(77 /88)of the gastric tumor tissues showed aberrant down regulation of miRNA -22 compared with adjacent non -tumor tissues (χ2 =69.32,P <0.05).Lower miRNA -22 level was strongly associated with T3 -T4 stage (χ2 =64.38,P <0.05)and lymph node metastasis(χ2 =68.56,P <0.05).The correlation statistical analysis results indicated that there were no significant differencec in sex,age and differentiation grade (all P >0.05 ). Conclusion The lower expression of miRNA -22 is associated with clinic pathological features.

Objective To investigate the advantages of BLADE technique in MR T2WI/TSE abdomen scanning. Methods 36 cases, which had obvious motion defects with conventional T2WI/TSE axial abdomen scanning because of psychology or disease, performed T2WI/BLADE/TSE scan with the same regions. Then the image quality was compared, and amendment of motion defects was reviewed. The equipment was SIEMENCE 3.0T scanner and phased-array coil. Results Motion defects of all images with T2WI/BLADE/TSE were attenuated with different degree compared with T2WI/TSE. All images with T2WI/BLADE/TSE satisfied the diagnostic demand. Conclusion The BLADE technique in abdomen scanning solves the difficult problem of impossible MR scan with uneven breath and trembling patients because of psychology or disease, and obtains good diagnostic imaging.

This article introduces ethical problems emerging in the imaging trials in clinical practice,and stresses the importance of protecting the privacy of volunteers and patients,and their legal rights of informed consent.This article also stresses the importance of the respect for the basic human right of volunteers and patients,and puts forward some countermeasures to promote the efficiency and reasonable supervision system in the clinical trials.Last but not least,it also emphasizes the significance of a personalized-style of care for volunteers and patients.

Objective To discuss the clinical value of magnetic resonance imaging in the diagnosis of inner ear lesion.Methods 94 patients who took magnetic resonance imaging water imaging were selected as study subjects from February 2014 to October 2016 in Heilongjiang Province Hospital.All the patients had surgical data,CT,MRI water imaging data.Based on the standard data of surgery gold,analyzed the sensitivity,specificity,accuracy,positive predictive value and negative predictive value of CT and MRI in the diagnosis of inner ear lesions,compared the statistical differences between the two methods of examination.Results The sensitivity,specificity,positive predictive value and negative predictive value of MRI water imaging in diagnosis of inner ear werehigher than CT,but the differences were no statistically significant (all P ＞ 0.05).In the case of abnormal vestibular aqueduct (x2 =7.265,P =0.015),cochlear deformity (x2 =5.042,P =0.028),diagnostic accuracy of cochlear fibrosis (x2 =5.492,P =0.027),the differences were statistically significant(all P ＜ O.05).Conclusion MRI water imaging can effectively provide the information of ear canal,eudometrial and other internal organs,can provide a favorable clinical diagnosis,it is worth to promote the application in the clinical work.

Objective To compare the effect of preoperative CTA examination using group injection test and group injection tracking delay protocol on image quality in patients with transcatheter aortic valve implantation(TAVI)/transcatheter aortic valve replacement(TAVR).Methods A total of 43 patients who underwent TAVI/TAVR preoperative one-stop CTA examination in our hospital were randomly divided into two groups,and preoperative CTA examination was performed using group injection tracking and group injection test.After the scanning was completed,the aortic root sinus(C1),the proximal left and right coronary arteries(C2,C3),the ascending aorta(A1),the abdominal aorta(A2),the left and right femoral arteries(A3,A4),and the CT value and SD value of the paraspinal muscles of the same layer were measured;the signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR)of the corresponding parts were calculated.The obtained data results were compared and analyzed from both subjective and objective aspects.Results There was no significant difference in image quality between the two groups in the aortic root sinus(C1),the proximal left and right coronary arteries(C2,C3),or the ascending aorta(A1)(P＞0.05).At the renal artery level,there was a significant difference in image quality between the abdominal aorta(A2)and the left and right femoral artery levels(A3,A4)(P＜0.05).Conclusion In the preoperative one-stop CTA examination of TAVI/TAVR patients,the CTA images below the renal artery level can obtain better image quality than the group injection tracking method.