Virtual reality technology is a kind of information technology,which can achieve the interaction between the users and the virtual environment by using relevant devices.This article introduces the application and validity of virtual reality technology in surgery of orthopedics,general surgery,neurosurgery and urology surgery and surgical training.It discusses the advantages and disadvantages and development prospects of the virtual reality technology in the field of surgery and surgical training as well.

Combined with practical experience, a stock investigation method of medicinal plants is approached from different angles, such as setting up the sample field and quadrant, doing the fieldwork, calculating the stock and annual possible gathering volume, etc. Depending on the geographical distribution features of the plants, the sample field are pointed out on topographic maps (1: 50 00 or 1: 10 000). Quadrants are set up at random or regularly according to the species and density of the plants. The locat ion, area, slop orientation, gradient,elevation, and vegetation of the sample field, also the area of quadrant and the amount of plants investigated, should be carefully noted down during the fieldwork .The quadrants are classified according to their slop orientation and gradient, then convert the recorded amonut of plants in quadrants to the amount of plants per square kilornetre. The stock of Per square kilometre is equal to the volume of the amount of the plants in per square kilometre divided by the amount of the plants per kilogram. The stock of per square kilometre multiplied by the area of earth's surface is the stock volume, which should be classified by the slop orientaion and gradient. The sum of the volunes is the total stock of a kind of plant.As to gather and make use of the medicinal plants in a gathering circle period, the annul possible gathering volume should be calculated as the stock volume of the plant divided by the gathering circle period.

Objective:To observe the accuracy of electronic method(EM), handing method(HM) and X-raying method(X-RM) in measuring root canal working length. Methods:Total 31 root canal in vivo were measured with HM, X-RM and EM(by the electronic apical locators-Root ZX and Raypex-5 respectively), and the data were compared with the actual root canal working lengths which were obtained from the sectional view's constrictions of the extracted teeth by magnifying glass. Results:Accuracy of working length measured by Raypex-5 was 93.55%, Root ZX was 87.10%, HM was 35.48%, and X-RM was 48.39%. Significantly statistical differences (P

Objective To investigate whether catestatin (bovine chromogranin A 344-364) can inhibit the biofilm formation of Candida albicans and examine its relationship with the expression of adhesion gene HWP1.Methods Clinical strains and standard strain ATCC 10231 of C.albicans were studied.XTT [2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide] method was used to assess the ability of C.albicans biofilm formation.Antifungal activity against planktonic Candida ceils was evaluated in terms of minimum inhibitory concentrations (MICs) according to the description in CLSI-M27-A3.XTT assay and colony count were used to assess the effect of catestatin on inhibiting C.albicans biofilm formation.The lowest concentration showing 50 ％ inhibition on biofilm formation (BIC50) was decided by calculating the metabolic activity.The adhesion of C.albicans reduced by catestatin was visualized under an inverted microscope and quantified by colony count.The expression of HWP1 was analyzed by RT-PCR.One-way analysis of variance (ANOVA) and Dunnett's T3 test were used to compare the results.Results Clinical strains and standard strain ATCC 10231 of C.albicans showed strong ability in forming biofilm.Catestatin exhibited MICs ranging from 40 μmol/L to 80 μmol/L against planktonic C.albicans cells,and BIC50 of 80-160 μmol/L in inhibiting C.albicans biofilm formation.Catestatin reduced the adhesion of C.albicans.The colony forming unit (CFU) was 27 822.22-±-2 472.74 in blank control group,while the CFU was 5 355.55± 1 264.03,11 377.78±2 232.58,17 488.89±1 136.27,22 377.78±3 521.99,and 26 044.44±1 329.57 in the presence of 160,80,40,20,and 10 μmol/L catestatin,respectively (F=147.018,P=0.001).The difference between control group and 160,80,and 40 μmol/L catestatin was statistically significant (P＜0.05).RT-PCR found the expression of HWP1 in the presence of 160 μmol/L catestatin was about 12.24％ of that in blank control group.Conclusions Catestatin can effectively prevent C.albicans biofilm formation.This effect may be related to the down-regulated expression of adhesion gene HWP1 by catestatin,which results in reduced adhesion of C.albicans.Promising clinical prospect is expected for this finding.

Objective To summarize and investigate the lethal factor of acute obstructive suppurative cholangitis (AOSC).Methods The clinical data of 56 patients with AOSC were retrospectively analyzed.Results Six cases died,5 cases with acidosis,5 cases with thrombocytopenia and 5 cases with temperature change obviously,4 cases with heart,lung and kidney disease or diabetes,5 cases with operation and operation time ≥ 150 min,5 cases with from onset to treatment time ≥72 h.Eighteen cases of elderly patients ≥70 years old,4 cases died.The patients whose age≥70 years,temperature ≥39 ℃ or ＜ 36 ℃,combined with acidosis,platelet counts ≤6.0 × 1012/L,with heart,lung,kidney diease or diabetes,time of anesthesia and operation ≥ 150 min and from onset to treatment time ≥72 h had higher death rate (P ＜ 0.05).Conclusion Age,obvious temperature abnormalities,significantly platelet decrease,with heart,lung,kidney diease or diabetes,acidosis,long time of anesthesia and operation and from onset to treatment time ≥ 72 h are the lethal factor of AOSC.

Objective To explore the application of high-frequency color Doppler in the diagnosis of infant intussusception and the selection of reduction mode according tO the hemodynamic situations of intussusception intestine tube and blood vessel in mesentery.Methods A total of 377 cases of doubtful intussusception infants wete checked by high-frequency color Doppler.After they had been diagnosed,the hemodynamic situations of intussuscepiton intestine tube and blood vessel in mesentery were carefully observed and the ultra-sound had 3 types and then the hydrostatic enema reduction was chosen as treatment method.Results A total of 263 cases was diagnosed by highfrequency colot Doppler with rate of coincidence of 100%.Among them are 253 successful cases reduced by hydrostatic enema.The successful rate of reduction was 96.2%and the 10 failed cases were changed to be treated bv operation.The intestinal wall of intussusception tube in failure group had serious dropsy without blood flow shown.Conclusions It is accurate that the infant intussusception is diagnosed by high-frequency color Doppler.According to the hemodynamic situations of intussusceptin intestine tube and blood vessel in mesentery,the infant intussusception can be divided into 3 types as follows:type Ⅰ:the blood signal of intestinal tube and wall is up or normal,which shall be reduced by hydrostatic enema;type Ⅱ:the blood signal of intestinal tube and wall is small with high obstruction index,which shall be reduced by hydrostatic enema as possible as it can;type Ⅲ:the intestinal wall has serious dropsy with rather high obstruction index and without blood flow shown,in which the hydrostatic enema redHetion shall bebanned and the operation shall be carried out as soon as possible.

Aim To establish a mouse breast cancer model stab-ly expressing HER2. Methods 4T1-Luc mouse breast cancer cell line was transfected with the full-length human HER2 gene and selected with G418. The HER2 expression in 4T1-Luc stable cells was detected by fluorescence-activated cell sorting ( FACS) and Western blot. 4T1-Luc/HER2 cells were implanted into the mammary fat pads of BALB/c or nude mice. After tumor stabili-zation, mice were randomly assigned into 4 groups for treatment with PBS control, chA21, Trastuzumab, or chA21 plus Trastu-zumab. Tumor volumes were measured and tumor growth inhibi-tion ratios were calculated twice a week. At the end of experi-ment, tumor metastasis in mice was detected by bioluminescence imaging technology. Results Several 4T1-Luc/HER2 stable cell clones were obtained after G418 selection. FACS and West-ern blot analysis showed that all clones expressed HER2 protein at high levels. These 4T1-Luc/HER2 clones showed good tumor-igenicity in mice with steady tumor growth after one week of cell implantation. After 2-3 weeks, metastatic tumor cells were seen in the lung, cheek and groin areas. In BALB/c mice, the tumor growth inhibition ratio was 43. 3% in chA21 plus Trastuzumab group (P<0. 05 vs PBS control), which was higher than chA21 group (11. 1%) or Trastuzumab group (23%). In addition, the luminescence number and density of tumor metastases in lungs were significantly reduced in the antibody combination group. Conclusions The mouse model of spontaneously metastasizing breast cancer with HER2 overexpression is successfully estab-lished. The preliminary study suggests that anti-HER2 antibody combination of chA21 and Trastuzumab has excellent inhibitory effects on tumor growth and metastasis.

Objective To explore the ultrasonographical characteristics of placental abruption, especially the light placental abruption that was diagnosed by color Doppler ultrasonic combining with enhancement Doppler E-flow imaging, providing diagnosis data for clinical treatment. Methods With color Doppler ultrasonic and enhancement Doppler E-flow imaging, an analysis was made on the ultrasonography and clinical result of 50 patients with heavy placental abruption and 23 patients with light placental abruption. Results The diagnosis and clinical treatment of 50 patients with heavy placental abruption who had been diagnosed by color Doppler ultrasonic combining with enhancement Doppler E-flow imaging were in conformity with the postnatal pathological diagnosis. The coincidence rate in diagnosis was 100%. Of 23 patients with light placental abruption who had been diagnosed by color Doppler ultrasonic combining with enhancement E-flow Doppler imaging, 19 cases' diagnosis and clinical treatment were in accordance with their postnatal pathological diagnosis and the coincidence rate was 83%, 4 cases were misdiagnosis and missed diagnosis. Of 73 patients with placental abruption, 60 cases were carried out caesarean birth and 13 cases performed natural labor. Conclusion The enhancement Doppler E-flow imaging combining with color Doppler ultrasonic can accurately diagnose the heavy placental abruption and also provide a new method for the diagnosis of light placental abruption and perform a dynamic monitoring for the treatment transfer result of it.

Objective To investigate the expression of the mRNA of muscle fibre types in the denervated post cricoarytenoid(PCA)muscle of rat.Methods Unilateral recurrent laryngeal nerve of eight rats were removed.Eight rats were used as controls.The mRNA expression of heavy chain myosin of PCA muscle fibre subtypes was measured with real-time quantitative RT-PCR in control rats and denervated rats 40 days after denervation.Results Compared to the control group,there were no significantly differences in mRNA expression of each muscle subtype between two groups.The ratio of MyHC type I to IIB was increased significantly(P=0.018).Conclusion The increased ratio of MyHC subtype I to IIB suggests the decreased contraction power of denervated PCA muscle.

OBJECTIVE: To explore the protective effect of calcium channel agonist BayK8644 preconditioning on the lungs against ischemia-reperfusion injury (I/R) and its mechanism in rabbits. METHODS: Forty rabbits were randomly divided into 4 groups (10 in each group): a sham-operated group (Sham), an I/R group (I/R), an ischemic preconditioning (IP) group (IP), and a BayK8644 preconditioning group(BayK8644).The wet to dry weight (W/D) ratio, superoxide dismutase (SOD) activity, myleoperoxidase (MPO), and malondialdehyde (MDA) contents of the lung tissues were measured after the operation. Morphological and ultrastructural changes of the lung tissue were observed by light and electron microscope. The expression of pulmonary surfactant-associated protein-A (SP-A) was examined with immunohistochemistry. RESULTS: The W/D ratio, MPO and MDA contents of the lung tissue in the BayK8644 group and IP group were significantly lower than those in the I/R group (P<0.05), while the SOD activity and expression of SP-A of the lung tissue in the BayK8644 group and IP group were significantly higher than those in the I/R group(P<0.05), The morphological changes and ultrastructural changes were less notable in the BayK8644 group and IP group, compared with the I/R group. There was no significant difference in SOD activity, MPO and MDA contents between the BayK8644 group and IP group (P>0.05). CONCLUSION Appropriate BayK8644 preconditioning can induce transient Ca²+ influx, and elicit strong protection against the lung ischemia-reperfusion injury, which can simulate the endogenous protective effect of ischemic preconditioning.
3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester ; pharmacology ; Animals ; Calcium Channel Agonists ; pharmacology ; Female ; Ischemic Preconditioning ; methods ; Lung ; blood supply ; Male ; Rabbits ; Random Allocation ; Reperfusion Injury ; prevention & control