High intensity focused ultrasound (HIFU) is a novel physical tumor therapeutic technology which applies the ultrasound well targeting, focusing, tissue absorbing property, and so on. It focused outer transducer low intensity ultrasound wave and targeted in the tumor, whichcan raise the temperature above 60℃ rapidly and induce tissue irreversible coagulation necrosis, with no damage to the surrounding normal tissue. It is a new physical tumor treatment technology.

High intensity focused ultrasound(HIFU) is a technique that ultrasound energy is focused on tumor target to function the treatment through the biological effects including heating effect, cavitation effect and mechanical effect of body to caused cell coagulation necrosis in vivo. Ultrasound contrast agent is one of the most important applicational agent for the treatment of hepatocellular carcinoma(HCC). We discussed in this paper the application of ultrasound contrast agent in the diagnose and focusing of target before the treatment and the assesement of treatment of HCC. Considering the enhancement of cavitation effect, better acoustic environment that enhance biological efficacy of HIFU during the treatment of HCC, ultrasound contrast agent is drawing more attention as an HIFU enhancement agent.

Objective To assess the influence of pre-exposure to non-ablating ultrasound on the effect of high intensity focused ultrasound(HIFU)ablation.Methods Forty rabbits with transplanted VX2 tumors on their livers were divided into three pre-exposure groups(60 W,80 W and 100 W)and a control group(O W),with 10 rabbits in each group.Each group was pre-exposed to lower intensity focused ultrasound at the corresponding power.From each group,5 rabbits were randomly selected to be exposed to HIFU on the next day.Each group received 14scans.The rabbits were sacrificed 24 h later to take tissue samples for tfipheny tetrazolium chloride(TTC)staining to measure the amount of coagulative necrosis.Hematoxylin and eosin(HE)staining and succinate dehydrogenase (SDH)were also measured to observe the structure and activation of pre-exposed tumors.Results After HIFU exposure,the ablated volumes increased with pre-exposure acoustic intensity,and all volumes were larger than those in the control group.The ablating efficiency in the 100 W group was the highest.The pre-exposure did not itself ablate tumor tissue,but in the 80 W and 100 W groups the structure and activation of the tissues changed.Those in the 60 W group were not obviously altered.Conclusion Prior exposure to non-ablating ultrasound can highly enhance the efficacy of HIFU ablation.

Objective To observe the pathological regression of rabbit liver after the low-dose irradiation with high intensity focused ultrasound (HIFU), and to explore the role and mechanism of the irradiation in changing acoustic environment of rabbit liver. Methods Pathological study was performed in 10 New Zealand white rabbits, the livers were observed under light and electron microscope. The observation was done immediately after low-dose HIFU irradiation and in 2, 3, 5, 7 days after the low-dose irradiation with HIFU. Results Light microscope changes: Edema existed in hepatocytes after irradiation instantly, congestion and aggravated edema were found at 2-3 days, then the injured cells recovered gradually. Electron microscope changes: Detached endothelial cells of hepatic sinusoid and swelling organelles were observed after irradiation, while 2 or 3 days later, erythrocyte aggregation was found in hepatic sinusoid and cavitation was found in cytoplasm. Thereafter, organelles swelling reduced till resumed to normal. Conclusion Low-dose HIFU irradiation can make corresponding changes to the acoustic environment of rabbit liver.

ObjectiveTo explore the PBL mode in training students' ability,improve the quality of teaching effect,in the teaching of Clinical therapeutic ultrasound and the teaching method based on problems with discussion method.MethodsTo 31 subjects of study who were randomly divided into five groups,each 6 people,a PBL teaching mode was used for 12 periods by proposing and study,group discussion,the whole class exchange and commenting on summary.ResultsThe survey shows that 93.6％ students think the teachers' design has gained their ends,71％ students are impressed by the knowlege and 96.8％ of the students show the good learning attitude,64.5％ of the students raised their interest in learning,which shows teaching results are effective.ConclusionPBL mode is superior to LBL teaching mode in training students' ability,improving the quality of teaching effect.

Requirement for Medical English teaching in physical medicine physicians training has been on the agenda to fit the new condition of globalization. According to the development of physical medicine in China and students English level, courses of medical English were set to match the requirements of both scientific research and clinic works. We try to improve students' medical English level through lectures in multimedia classroom and a lot of practical activities after class.

Objective To identify an suspected Vibrio cholerae isolated from Xiangyang Central Hospital and characterize the strain in terms of antibiotic resistance and relevant virulence genes.Methods Pathogen identification and susceptibility testing were completed with MicroScan WalkAway 40 Automated Microbiology System.Slide agglutination was used for serotyping. PCR and sequencing technology were employed for 16s RNA gene analysis.PCR technique was used to detect six major viru-lence genes.Results This suspectedVibrio cholerae isolate was confirmed as non-O1 and non-O139 Vibrio cholerae .Suscep-tibility testing results indicated that the strain was sensitive to ampicillin,chloramphenicol,trimethoprim-sulfamethoxazole, and tetracycline.16s RNA gene sequence analysis showed 100% homologous with the registered sequence in National Center for Biotechnology Information database.Virulence genes rtxC and toxR were identified.The other virulence genes such as tcpAET,ctxA,hlyA,and tcpACL were negative.Conclusions This suspected Vibrio cholerae isolate is confirmed as non-O1 and non-O139 Vibrio cholerae .The pathogenic factors may be related to the virulence genes rtxC and toxR.

Objective To observed the effect of high-intensity focused ultrasound (HIFU) in combination of submicrobubble on ablation of breast tumor VX2 in rabbits.Methods Submicrobubble was prepared,and the appearance,distribution,diameter,and zeta potential were measured.The rabbits were injected with the tumor tissue suspension in bilateral breast tissues.HIFU(150 W,120 W,5 s,3 s) combined with submicrobubble to damage rabbit breast VX2 tumors.The coagulation necrosis was assessed by HE staining.The grayscale changes of the target area before and after HIFU irradiation were recorded automatically by computer.Results The diameter of the submicrobubble was 498.9 nm on average.HE staining showed the area of coagulation necrosis was significantly larger in the HIFU + submicrobubble group than the HIFU + PBS group.The injury range of 150 W irradiation was larger than that of 120 W irradiation,given the same irradiation time.The injury range of 5 s irradiation was larger than that of 3 s irradiation,given the same irradiation strength.The gray scale change in the target area was significantly higher in the HIFU + submicrobubble group than the HIFU + PBS group.Conclusions The submicrobubble exhibited sound imaging performance,and it can be use in the ultrasound therapeutics in the future.

Objective To discusse the influence of permeating perfluoropentane drops-encapsulated mesoporous silica nanocapsules (MSNC-PFP) on HIFU surface ablation in vitro bovine liver.Methods Fifity bovine liver tissues were divided into 5 groups:Control group,0.25 mg/ml group,0.50 mg/ml group,1.00 mg/ml group,2.00 mg/ml group according to the concentration of MSNC-PFP.The synergistic agent was injected along the ablation line path under the guiding of ultrasound.The surface ablation model was structured by 6 coagulation necrosis side by using HIFU linear scanning,inner region without melting,and the ultrasonographic changes were observed in the melt area.The coagulation necrosis range was assessed by TTC staining,and necrosis degree was observed by HE staining.The coagulation necrosis volume was measured,the coverage index (CI),external volume index (EI),energy efficiency factor (EEF) were used to evaluate the ablation effect in each group.Results The MSNC-PFP more than 1.00 mg/ml was shown as strong echo in ultrasonic image,fade after 3-5 min.The grey value was changed in HIFU ablation area related to the concentration of MSNC-PFP.The total ablation volume of 0.50 mg/ml group,1.00 mg/ml group,2.00 mg/ml group were more than control group,the EEF was lower than that of the control group (all P＜0.01).The CI and EI of 1.00 mg/ml group and 2.00 mg/ml group were higher than those of the other group (all P＜0.01).The coagulation necrosis became complete when the concentration of MSNC-PFP above 0.50 mg/ml.Conclusion MSNC-PFP can increase the volume of coagulation necrosis,decrease the EEF and increase the efficiency of HIFU surface ablation of bovine liver in vitro.

Objective To investigate the condition and causes of needle-stick injuries among health care workers(HCWs), and explore effective strategies for preventing needle-stick injuries.Methods Needle-stick injuries recorded by healthcare-associated infection management department in a hospital between January 2013 and December 2015 were surveyed retrospectively.Results 164 HCWs suffered needle-stick injuries, including 71 (43.29%) doctors, 81 (49.39%) nurses, and 12 (7.32%) other HCWs.The number of injuries in 2013, 2014, and 2015 were 47(28.66%), 54(32.93%),and 63(38.41%)respectively.152(92.68%), 9(5.49%),and 3(1.83%)injuries were caused by contaminated medical instruments, uncertain-contaminated medical instruments, and non-contaminated medical instruments.Among 164 cases of needle-stick injuries, 67(40.85%) occurred in operating rooms, 141 (85.98%) were finger injuries;the main causes of needle stick injuries were carelessness, busy work and nonstandard manipulation(n=115, 70.12%), most doctors suffered needle stick injuries due to the lack of experience (52.11%), most nurses suffered needle stick injuries due to carelessness, busy work and nonstandard manipulation(93.83%).Conclusion Needle stick injuries among HCWs increased year by year, strategies should be implemented to reduce the occurrence of needle injuries, including strengthening occupational protection consciousness among HCWs, strengthening construction of healthcare-associated infection management system, and improving medical environment.