The da Vinci Surgical System has developed and great progress has been made recently in surgery. Despite lack of applications in tumors of head and neck, its advantages, such as minimally invasive procedure and rapid recovery, show great prospects. In this article, we reviewed the surgical method, indication, advantages and prospects of its application in tumors of head and neck.

ObjectiveTo evaluate the effects of aerobic exercise, nutrition or both on physical fitness and metabolism in obesity adolescents. Methods94 overweight/obese adolescents (12～16 years old) underwent 10 weeks exercise alone, nutrition intervention alone, and exercise combined with nutrition, respectively. The physical and metabolism index were detected before and after intervention. ResultsThe body mass index (BMI), body fat, body fat% decreased in all the groups. Especially, exercise alone decreased total cholesterol (TC), increased fasting insulin (FINS), insulin resistance (HOMA-IR), and function of β-cells (HOMA-β). Nutrition alone decreased TC, low-density lipoprotein cholesterol (LDL-C). Exercise combined with nutrition decreased TC and LDL-C, increased FINS and HOMA-β. High-density lipoprotein cholesterol (HDL-C) tended to decrease in all the groups. ConclusionThe aerobic exercise and /or nutrition intervention can improve the lipid metabolism, Exercise can improve function of the β-cell of pancreas. But the effects of exercise and/or nutrition on HDL-C and insulin resistance are not satisfactory.

Objective:To investigate the ability of fluoride toothpaste and fluoride varnish on enamel remineralization and acid resist-ance.Methods:Enamel specimens were prepared from bovine incisors,and were randomly divided into 4 groups(n=3)after acid-etching by 37%phosphoric acid.Specimens in group A(control)was processed daily with normal saline;those in group B and C were treated once with Duraphat varnish and Fluor Protector varnish respectively;in group D was daily processed with fluoride toothpaste. All specimens were incubated in artificial saliva for 2 weeks.Then all specimens received acid-etching again.Micro-hardness test, SEM observation and image analysis were performed before and after each step.Results:After 2 weeks of processing,no remineraliza-tion was found in group A.Varnish layers were observed on the surface of specimens in group B and C.In group D remineralization was detected on the enamel surface.After re-etching,micro-hardness decreased in group A and D.Fluoride varnish layers in group B and C showed strong resistance to acid-etching.After re-etching,area of micro-holes in group A and D increased(P<0.05 ),but that in group D was smaller than in the control(P<0.05).No micro-hole was observed in group B and group C.Conclusion:Protec-tive layer formed on the enamel surface by fluoride varnish is resistant to acid-etching and promotes enamel remineralization.Fluoride toothpaste application can promote enamel remineralization,but with less resistance to acid.

Objective To study CT findings, diagnosis and differential diagnosis for prostate cancer. Methods 28 cases with prostate cancer confirmed by surgery and pathology, of them 4 cases were recurrence after operation. Results In 24 cases confirmed by surgery 21 (87.5%) were diagnosed by CT. Their CT appearances were : (1) Focus: in non enhanced scanning the prostate was enlarged unevenly in 18 cases. The density of the mass was slightly lower than the normal prostate in 17 cases, and equal to normal in 11 cases. Patchy calcification was seen in 2 cases moderate. In enhanced scanning, 22 cases showed nodular enhancement but slightly less than normal, 6 cases were equal to normal. (2) Metastastic lesions: 8 cases had local thickened bladder wall, 4 cases had enlarged seminal vesicle with unneven density, 2 cases with thickened anterior wall of rectum.And pelvis mass, enlarged lymph nodes, bony destruction of pelvis and pulmonary metastasses 1 case for each respectively. Conclusion (1) It is emphasized enhanced CT study should be a routine examination in the diagnosis of prostate cancer by CT; (2)CT can define the extent of the lesion and metastases thereby helpful to predict the prognosis and evaluate the effect of treatment.

BACKGROUND: Some scholars have used finite element analysis to simulate spinal biodynamics. But there are few reports on finite element imitation of lumbar biodynamics system before and after artificial disc replacement. OBJECTIVE: This study aimed to do finite element analysis by establishing new three dimensional finite element models of SB-Chaite Ⅲ lumbar disc replacement. DESIGN, TIME AND SETTING: The observational experiments were performed at the Laboratory of Orthopaedics of Xiangya Hospital of Central South University from December 2003 to August 2004. PARTICIPANT: A healthy male volunteer served as simulation. His T12-S1 underwent continuous CT scanning. There were altogether 264 images with 2 mm in thickness each. Three-dimensional images were reconstructed every 15? in order to obtain the data for three-dimensional model. METHODS: The CT images and human anatomical data were processed by 3DSMAX software to establish three-dimensional L4-5 model of normal Chinese males. MAIN OUTCOME MEASURES: It was transformed to finite element model after processed by SAP2000 software together with SB-Chaite Ⅲ disc prosthesis model. RESULTS: The three-dimensional model and finite element model of lumbar spine were successfully established. The finite element model of SB-Chaite Ⅲ disc replacement in L4-5 spine was established. The total nodes were 2 542, including 1 924 Solid units, 592 Area units and 50 Link units. CONCLUSION: The finite element model of artificial disc replacement can be established by CT scanning, digital processor and computer aided design.

Objective To investigate the correlation between high myopia and MMP-2 in aqueous humor (AH), by comparing the protein level of MMP-2 in AH from patients with cataract combined with high myopia and with emmetropia. Design Experimental study. Participants 30 AH samples of patients with age-related cataract. Methods AH samples were collected from the patients with age-related cataract during phacoemulsification, including 15 AH samples from patients combined with high myopia (experimental group) and 15 AH samples from patients with emmetropia (control group). The expression of pro-MMP-2 and MMP-2 in AH were ana-lyzed by Western blot technique. Main Outcome Measures The gray value of MMP-2 protein band detected by Western blot. Results The level of pro MMP-2 was statistically higher than that of MMP-2 in experimental group (430.4±57.3 versus 294.5±35.2, t=10.400, P= 0.000) and control group (402.8±57.7 versus 280.3±49.7, t=8.400, P=0.000). There was no statistically difference in the level of pro-MMP-2(t=1.320, P=0.200)and MMP-2 (t=0.900,P=0.375) between the two groups. Conclusions No abnormal expression of MMP-2 was detected in AH from patients with high myopia, according to this study based on limited samples. Pro-MMP-2 was the main form of MMP-2 in AH of patients with cataract combined with high myopia or emmetropia, which possessed potential ability of transferring into form of active MMP-2. (Ophthalmol CHN, 2009, 18: 260-264)

Objective To learn the policy outcomes of the management of category-B large medical instruments deployed in Beijing.Methods Call into play the data from the surveys made in 2005,2007 and 2010 on the five types of category-B large medical instruments deployed in the city.Summarize and analyze the outcomes of such instruments in terms of their total configuration volume,and the growth,distribution and use.Results From 2005 to 2010,CT scored the fastest growth of these five types of instruments,with 48 units deployed; SPECT was the lowest,with 8 units deployed.Conclusion The volume growth,instruments distribution,and use efficiency of such instruments in Beijing are rationally evolving,which proves that the deployment and management of category-B large medical instruments is compliant with conditions of the city.

[ ABSTRACT] AIM:To establish the insulin resistance rat model for evaluating the correlation of omentin-1 level and insulin resistance.METHODS: SPF male Wistar rats ( n =30 ) were randomly divided into normal control group (NC, n=15) and high-fat diet group (HF, n=15).The rats in NC group were fed with basic diet.The insulin resistant model was established by feeding the rats with high-fat diet in HF group.After 10 weeks, 5 rats in each group were as-sessed by the technique of hyperinsulinaemic-euglycaemic clamp.After the insulin resistant model was successfully estab-lished, the body weight and fasting blood glucose were detected.The concentration of fasting serum omentin-1 was analyzed by ELISA.Fasting serum insulin was measured by radioimmunoassay.RESULTS: No difference of fasting blood glucose between the 2 groups was observed.The level of fasting serum insulin in HF group was significantly higher than that in NC group ( P <0.05 ) .The level of serum omentin-1 in HF group were significantly decreased compared with NC group (P<0.01).Pearson’s correlation analysis showed that negative correlations between serum omentin-1 and fasting serum insulin (r=-0.654,P<0.01), serum omentin-1 and free fatty acid (r=-0.446, P<0.05) was found.CONCLU-SION:In rats, serum omentin-1 level began to decrease at insulin resistance stage.As serum omentin-1 level decreased, the basal insulin level increased, indicating that decreased serum omentin-1 level may be an early factor of IR, diabetes and cardiovascular diseases.

Objective To study the anatomical characteristic of nanophthalmos with ultrasonography and its clinical significance. Methods Forty-four nanophthalmic eyes (22 patients) and 200 normal eyes (100 persons) were included. A series of ocular parameters, including ocular axial length, angle between trabeculum and iris,thickness of lens and sclera.and vitreous cavity length were measured with ultrasound A-scan and ultrasound biomicroscopy. The refractive status was examined with dioptometry. Results The ocular axial length[(15. 95±0. 76)mm] and vitreous cavity length [(8. 48±0. 90)mm] were shorter, the lens [(4. 9±0. 53)mm] and sclera [(0. 917±0. 119)mm] were thicker in nanophthalmic eyes than those of normal eyes( P <0.01). The relative position of lens (0.312±0.09) was more forward, and the angle between trabeculum and iris (11. 41 ±7. 63 ) was narrower in nanophthalmic eyes, compared with normal eyes( P <0. 01). The hyperopia of nanophthalmic eyes was negatively correlated with the ocular axial length ( r = -0.806) and vitreous cavity length ( r = - 0. 663) ( P <0. 01). Conclusions Nanophthalmos was characterized by short ocular axial length, thick lens and sclera.and narrow anterior chamber angle. The thickness of sclera and the angle between trabeculum and iris measured with ultrasound biomicroscopy could provide a solid indication of the treatment to the complication of angle closure glaucoma.

Objective To compare the characteristics of intrahepatic cholangiocarcinoma (ICC) and different differentiated hepatocellular carcinoma (HCC) by CEUS and evaluate the diagnostic value of CEUS.Methods The cases who underwent CEUS and were pathologically demonstrated as ICC (n=34) and HCC (n=136) were observed.The characteristics of ICC and different differentiated HCC in conventional ultrasound and CEUS were analyzed,and the diagnostic efficiency of wash out time were calculated.Results ICC had higher percentage (24/34,70.59％) of washout emerging in early portal phase than those of HCC.And ICC had lower percentage (0;4/34,11.76％) of washout emerging in middle and late portal phase than poorly and moderate differentiated HCC.Poorly differentiated HCCs had higher percentage (16/41,39.02％) of washout emerging in middle portal phase than well differentiated HCC.The sensitivity,specificity,positive predictive value,negative predictive value,accuracy,positive likelihood ratio and negative likelihood ratio of washout time in diagnosis of ICC were 82.35 ％ (28/34),91.18％ (124/136),70.00％ (28/40),95.38％ (124/130),89.41％ (152/170),9.4,0.2,respectively.The rise time of ICC and well,moderate and poorly differentiated HCC were (13.03 ± 3.49) s,(13.80 ± 3.04)s,(14.89±4.12)s,(16.00±3.38)s,respectively,and the difference was significant (F=4.369,P＜0.05).The rise time of ICC was significantly higher than that of well differentiated HCC (P＜0.05).Conclusion The CEUS performances are different significantly among ICCs and different differentiated HCCs,which has value for the differential diagnosis.