Objective To propose an improved C-means segment method based on Gibbs random field accelerated by GPU.Methods The parallel computation of pixel shades was used to take the place of the classical point-by-point method of CPU.By this way,the efficiency was higher than merely using the CPU computation.Results The efficiency of computation was improved over 400%.The load of CPU was reduced and the effect of accelerator was obvious.Conclusion The improved C-means segment method based on Gibbs random field accelerated by GPU enhances the clinical application of image segmentation,the computer rate of which is improved distinctly and closely to real time.[Chinese Medical Equipment Journal,2008,29(2):6-9]

Objective To explore the formation process of vacuum pressure differential of micro power negative pressure technology to facilitate its clinical application.MethodsThe formation of negative pressure differential and changes of negative pressure values in enclosure space were studied which was formed by liquid aspiration after the compressive polyvinyl alcohol foam material was enclosed.Micro power negative pressure technology was applied to the treatment of the right ear necrosis patient after focal cleaning,and the efficacy was observed.Results Medical adhesive film was raised gradually during the expansion of polyvinyl alcohol foam due to liquid aspiration,and then the enclosure space extended increasingly to form local vacuum negative pressure.The range of maximal negative pressure was between-110 and-200 Pa,and the mean maximal negative pressure value was-132.7 Pa.Micro power negative pressure technology behaved well in healing the wound.Conclusion Micro power negative pressure technology gains advantages in reliability and easy operation over other technologies and products,and may be a new choice for healing of refractory wounds.

The remote monitoring and alarming system of the level & pressure of the liquid-oxygen tank employes two microprocessors and remote control technique to fulfill its functions.With a cable and a video connection wire involved,the system is simple,safe,reliable and lightingproof.

Objective To determine the median effective target effect-site concentration (EC50) of sufentanil when intraoperative wake-up test was successful in patients undergoing scoliosis surgery.Methods Ninety ASA Ⅰ or Ⅱ patients,aged 18-64 yr,with body mass index ＜ 30 kg/m2,scheduled for scoliosis surgery under sevoflurane and sufentanil anesthesia,were randomly divided into Ⅰ-Ⅵ groups (n =15 each).Anesthesia was induced with sufentanil,etomidate and cisatracurium,and maintained with sevoflurane,sufentanil and cisatracurium.The patients were tracheal intubated and mechanically ventilated.Before the wake-up test,infusion of cisatracurium was stopped and the end-tidal concentration of sevoflurane was adjusted to 0.The EC50 was determined by the K(a)rber method.The target effect-site concentration of sufentanil was set at 0.19 ng/ml in group Ⅰ,0.18 ng/ml in group Ⅱ and gradually decreased in decrements of 0.01 ng/ml.The wake-up test was performed 5 min later.The EC50 and 95 ％ confidence interval of sufentanil were calculated by the K(a)rber method.Results EC50 of sufentanil obtained was 0.164 ng/ml and 95％ confidence interval of sufentanil obtained was 0.157-0.172 ng/ml when the wake-up test was successful.Conclusion The EC50 of sufentanil is 0.164 ng/ml when the intraoperative wake-up test is successful in the patients undergoing scoliosis surgery.

Objective To investigate the risk factors for postoperative delirium in patients undergoing noncardiac surgery. Methods From September-December 2009, 480 patients undergoing elective noncardiac surgery were included in this study. The criteria for enrolment of the patients in this study were (1) age ≥ 65 yr,(2) age ＜ 65 yr if associated with coronary artery disease, hypertension, diabetes mellitus, brain injury, cerebral hemorrhage, cerebral infarct, emphysema, chronic bronchitis; duration of operation ≥ 3 h and intraoperative blood loss was expected to exceed 20% of blood volume. The diagnosis of delirium was based on Confusion Assessment Method (CAM). Multivariate logistic regression was used to analyze the risk factors for postoperative delirium.Results Postoperative delirium developed in 79 patients during the first three postoperative days. The incidence of postoperative delirium was 16.5%. The logistic stepwise regression analysis indicated that the risk factors for delirium included advanced age, method of anesthesia, long operation, postoperative pain, emphysema and alcholic. Conclusion Age, method of anesthesia, long operation, postoperative pain, emphysema and alcholic are risk factors for postoperative delirium in patients undergoing noncardiac surgery.

Objective To clone and express the alkaline protease AprA , one important virulence factor secreted by Pseudomonas aeruginosa(PAE)in Escherichia coli, to clone and express the inhibitor of AprA (AprI) and its substrate flagellin , and to detect the function of AprA and the inhibitory function of AprI .Methods The genes encoding AprA ,AprI and flagellin gene were amplified respectively by PCR using PAE PAO 1 genome DNA as the template .The expression vec-tors (pET-28a-AprA, pET-28a-AprI and pET-28a-Flagellin) were constructed and transformed into E.coli BL21(DE3) respectively.The recombinant AprA protein was expressed by IPTG induction and purified via denaturing and renaturation. The recombinant AprI and flagellin were expressed and purified by Ni 2+affinity chromatography .The cleavage activities of AprA on flagellin were detected by SDS-PAGE.Results Recombinant AprA , AprI and flagellin protein were expressed and purified .It was demonstrated that AprA cleaved flagellin , which was blocked by AprI .Conclusion Recombinant AprA could cleave its substrates as an alkaline protease , and its inhibitor AprI inhibits the activities of AprA .This study will contribute to further investigations on the role of AprA in the pathogenesis of PAE .

Objective To investigate the risk factors of severe hand,foot and mouth disease (HFMD).Methods 175 severe cases of HFMD and 183 mild cases of HFMD in the same period were randomly selected.Single factor analysis was first performed between severe and mild cases on age,gender,residence,symptoms,signs and laboratory examinations,etc,to screen out the related risk factors which P value ＜ 0.05.Then,binary logistic regression analysis was carried out to determine risk factors most related to severe HFMD.Finally,receiver operating characteristic curve (ROC) analysis was performed on severe HFMD related risk factors.Results Single factor analysis showed that there were obvious differences between children with mild HFMD and those with severe HFMD in the factors like difficulty in breathing,walking instability,vomiting,limb shaking,disturbance of consciousness,convulsions,cold sweat and weakness,thermal process,the degree of fever,pulmonary rales,heart rate,serum EV71 antibody,circulatory failure,leukocyte count,platelet count,neutrophil ratio,CRP,blood glucose,etc (x2 =15.236,19.819,33.823,52.670,12.984,10.180,29.318,52.932,34.544,14.615,46.633,31.407 and 5.303,t =3.184,3.144,2.256,2.244 and 2.828,,all P ＜0.05).Binary logistic regression analysis showed that the thermal process,startle tremor or limb jitter,serum EV71 antibody,vomiting,fever,neutrophil ratio were the related risk factors of severe HFMD (B value =2.605,2.129,1.409,1.185,0.841 and 0.103,all P ＜ 0.05).ROC analysis showed that the areas under the curve of the predicted probability and thermal process were larger than any other risk factors [(95％ CI (0.888 ～ 0.961) and (0.818 ～ 0.920)],and thus had better diagnostic values.Conclusion Children under 3 years old were the high risk population of HFMD.Such clinical symptoms as persistent high fever,vomiting,startle tremor orlimb jitter,EV71 antibody in serum and increasing neutrophil ratio were risk factors for severe HFMD.The predicted probability had more diagnostic value than any other risk factors.

Objective to establish an ethical assessment system in the admittance of the limitative medical technologies.Method:literature review and Delphi method are employed to adjust and set the structure,index numbers,and index weights of ethical assessment system of the limitative medical technologies.Result:An ethical assessment system in the admittance of the limitative medical technologies was established,which included 3 primary indices,11 secondary indices and 35 tertiary indices.There were 4 qualitative levels with different weights in tertiary indices,based on which the global grade and proposed-admittance criterion were obtained.Conclusion:Establishment of ethical assessment system in the admittance of the limitative medical technologies provides an ethical evidence for the assessment of clinical admittance of the limitative medical technologies with qualitative and quantitative approaches and class-setting evidence.

Objective To investigate the effect of the intraoperative wake-up test on the postoperative delirium in patients undergoing scoliosis operation under analgesia with sufentanil. Methods Sixty ASA Ⅰ or Ⅱ patients , aged 12-60 yr, scheduled for scoliosis surgery, were randomly divided into 2 groups ( n = 30 each) : control group (group C) and intraoperative wake-up test group (group W) . The intraoperative wake-up test was not performed during operation in group C. Anesthesia was induced with target-controlled infusion of sufentanil with the target effect-site concentration set at 0.5 ng/ml and iv injection of propofol 1-2 nig/kg. As soon as the patients lost consciousness, tracheal intubation was facilitated with 0.15 mg/kg cisatracurium besylate. The patients were mechanically ventilated. Anesthesia was maintained with target-controlled inhalation of sevoflurane (target end-tidal concentration 0. 8%-1. 5%), target-controlled infusion of sufentanil (target effect-site concentration 0.2-0.3 ng/ml) and iv infusion of cisatracurium besylate 0.1 mg- kg-1·h-1 . In group W, the patients underwent the intraoperative wake-up test. Postoperative analgesia was provided with sufentanil. The occurrence of intraoperative awareness and postoperative delirium was recorded. Results No significant difference was found in the incidences of intraoperative awareness and postoperative delirium between the two groups. Conclusion The intraoperative wake-up test is not the risk factor for postoperative delirium in patients undergoing scoliosis surgery under analgesia with sufentanil, and inhibition of perioperative pain and intraoperative awareness by analgesia with sufentanil may be involved in the mechanism.

ObjectiveTo compare the intraoperative wake-up test in patients undergoing scoliosis surgery with different anesthesia methods.MethodsForty ASA Ⅰ patients aged 13-18 yr with body mass index ＜ 30 kg/m2 scheduled for scoliosis surgery were randomly divided into 2 groups ( n =20 each): propofol combined sufentanil anesthesia group (group P) and sevoflurane combined sufentanil anesthesia group (group S).Anesthesia was induced with target-controlled infusion of sufentanil(target effect-site concentration 0.5 ng/ml),and iv injection of etomidate 0.3 mg/kg in both groups.Tracheal intubation was facilitated with 0.15 mg/kg cisatracurium when patients lost consciousness.The patients were mechanically ventilated.Anesthesia was maintained with target-controlled inhalation of sevoflurane (target end-tidal concentration 0.8％-1.5％ ) in group S,and target-controlled infusion of propofol (target plasma concentration 3-5 μg/ml) in group P,and target-controlled infusion of sufentanil (target effect-site concentration 0.2-0.3 ng/ml),and iv infusion of cisatracurium 0.1 mg· kg-1· h-1 in both groups.BIS value was maintained at 40-60.Cisatracurium administration was terminated and target effect-site concentration of sufentanil decreased to 0.1 ng/ml before wake-up test,5 min later,sevoflurane and propofol administration were terminated,and 5 min later wake-up test was performed.MAP and HR were recoreded during wake-up test.The wake-up time and advers effect (bucking,restlessness and awareness)were recorded.Results The wake-up time was significantly shorter in group S than in group P( P ＜ 0.05).MAP and HR were in normal range during wake-up test in both groups,and bucking,restlessness and awareness were not found in both groups.ConclusionTarget-controlled inhalation of ssvoflurane combined with sufentanil can be safely and effectively used for intraoperative wake-up test in patients undergoing scoliosis surgery,and the wake-up time is shorter than that with propofol combined sufentanil,and it is an apporiate anesthetic technique for the intraoperative wake-up test.