Traditional sample entropy fails to quantify inherent long-range dependencies among real data. Multiscale sample entropy (MSE) can detect intrinsic correlations in data, but it is usually used in univariate data. To generalize this method for multichannel data, we introduced multivariate multiscale entropy into multiscale signals as a reflection of the nonlinear dynamic correlation. But traditional multivariate multiscale entropy has a large quantity of computation and costs a large period of time and space for more channel system, so that it can not reflect the correlation between variables timely and accurately. In this paper, therefore, an improved multivariate multiscale entropy embeds on all variables at the same time, instead of embedding on a single variable as in the traditional methods, to solve the memory overflow while the number of channels rise, and it is more suitable for the actual multivariate signal analysis. The method was tested in simulation data and Bonn epilepsy dataset. The simulation results showed that the proposed method had a good performance to distinguish correlation data. Bonn epilepsy dataset experiment also showed that the method had a better classification accuracy among the five data set, especially with an accuracy of 100% for data collection of Z and S.
Algorithms ; Electroencephalography ; Entropy ; Epilepsy ; diagnosis ; Humans ; Multivariate Analysis ; Nonlinear Dynamics

BACKGROUND: There is still no satisfactory therapy for thetreatment of cerebral infarction at present. Although sub-hypothermia is effective in the treatment of cerebral infarction, its side effect is relatively more. Local sub-hypothermia might have favorable effects in the treatment of cerebral infarction.OBJECTIVE: To observe the protective effects of local sub-hypothermia on the ischemic brain tissues in rats to further explore its mechanism.DESIGN: A randomized controlled basic study based on the experimental animals.SETTING: Institute of neurology of a university hospital.MATERIALS: The study was conducted in the Animal Laboratory of Neurology, the First College for Clinical Medicine, Harbin Medical University between April 2000 and January 2002. Fifty male Wistar rats(cleanness grade) with a bodyweight of(250 ± 25) g were selected.INTERVENTIONS: Ten rats were randomly selected from the 50 rats and divided into normal group and sham-operation group with 5 rats each. The rest 40 rats were randomly divided into normal temperature cerebral ischemia group and local hypothermia cerebral ischemia group with 20 rats each. Rat cerebral middle-sized arterial ischemia model was established for local sub-hypothermia disposal.MAIN OUTCOME MEASURES: Impacts on cerebral infarction volume,nerve function, and neuron-specific enolase(NSE) of rats in each group.RESULTS: The cerebral infarction volume at 48 hours after embolism in rats was ( 128.95 ± 13.42) or (84.90 ± 11.36) mm3 respectively, nerve function evaluation was( 1.60 ± 0. 24) or (0. 95 ± 0. 17), and serous NSE concentration was(13.55±4.07) or(9.19±3.42) μg/L in either sub-hypothermia group or normal temperature group, which were significantly different from each other.CONCLUSION: Local sub-hypothermia therapy has protective effects on ischemic cerebral neurons.

Objective To observe the change of platelet activity marker in hypertensive patients complicated with ischemic cardiovascular and cerebrovascular disease ,and assess it s value in the happening of thrombotic disease. Method The platelet activity marker (CD62p,CD63) were measured by flow cytometry in 40 hypertensive patients complicated with ischemic cardiovascular and cerebrovascular disease (group C ),46 hypertensive patients not complicated with ischemic cardiovascular and cerebrovascular disease (group B),and 30 cases of healthy control (group A). Comparison between three groups were made. The serum fibrinogen were measured at the same time. Result serum level of CD62p, and CD63 in group B,C are higher than group A.(P

OBJECTIVE To investigate the prevailing strains of pathogens of hospital acquired infections in ICU and their drug-resistances in order to provide treatment basis for critical and severe patients in fighting against infection.METHODS A retrospective investigation analysis was made for all the isolated bacteria as well as their drug-resistance in our hospital from Jan 2000 to Dec 2005.RESULTS Totally 869 bacterial strains were isolated which included 666 strains of G-bacteria(74.3%),and 230 strains of G+bacteria(25.7%).The G-bacteria included Pseudomonas aeruginosa,Klebsiella pneumoniase,Escherichia coli,Acinetobacter baumannii,etc,which were isolated mainly from respiratory tract.The G+ bacteria consisted of Staphylococcus and Enterococcus.Staphylococcus were mainly isolated from respiratory tract and Enterococcus from urinary tract.Bacteria were highly resistant to commonly used antimicrobials and demonstrated multi-drug resistance.The isolated rate of G+bacteria and drug resistance of G-bacteria to the commonly used antibiotics was increasing yearly.CONCLUSIONS The pathogens are mainly isolated from respiratory tract and the most are G-strains and multi-drug-resistant.The selection and use of antibiotics should be based on the results of drug-sensitivity tests.

Objective: To explore influence of exercise on cardiac autonomic nerve function in patients undergoing coronary artery bypass grafting (CABG) and its clinical significance. Methods: A total of 53 patients with coronary heart disease undergoing CABG were randomly divided into routine treatment group (n=25) and rehabilitation group (n=28, received exercise training based on routine treatment). Changes of autonomic nerve function before, second and eighth week after CABG were analyzed in two groups using time domain indexes of heart rate variability (HRV) by ambulatory electrocardiography, including standard deviation of normal to normal RR intervals calculated over the 24 h period (SDNN), standard deviation of normal to normal RR intervals in all 5 min segments of the entire recording (SDANN), root-mean square of differences between successive normal to normal intervals (rMSSD) and adjacent normal RR interval difference > 50ms stroke accounted for a percentage of 24h total RR interval (PNN50). Results: Compared with before CABG, there were significant decrease in SDNN, SDANN, RMSSD and PNN50 in both groups two weeks after CABG (P<0.05~0.01); eight weeks after CABG, above indexes recovered to levels before CABG in routine treatment group[SDNN （113.6±29.4）vs.（116.7±24.7）, SDANN（112.2±32.1）vs.（113.6±28.6）, rMSSD（21.9±8.2） vs.（23.2±7.1）, and PNN50 （7.5±4.2）vs.（8.2±3.7）] , P>0.05 all; Compared with before CABG, there were significant improvements in SDNN [(114.7±25.2) ms vs. (132.6±30.6) ms], SDANN [(111.6±23.5) ms vs. (129.2±30.8) ms], rMSSD [(24.2±8.7) ms vs. (29.9±7.5) ms] and PNN50 [(7.8±2.2) ms vs. (9.5±2.3) ms], and there were significant improvement than those of routine treatment group [SDNN （132.6±30.6）vs.（113.6±29.4）, SDANN（129.2±30.8）vs.（112.2±32.1）, rMSSD（29.9±7.5）vs.（21.9±8.2）and PNN50 （9.5±2.3）vs.（7.5±4.2）] eight weeks after CABG in rehabilitation group, P<0.05 all. Conclusion: All HRV indexes significantly decrease on two weeks after CABG in both groups, suggesting that CABG can damage cardiac autonomic nerve system. These indexes of rehabilitation group were more improvement than those of routine treatment group, suggesting exercise training can more significantly improve cardiac autonomic nerve function after CABG.

Objective To evaluate the value of contrast-enhanced CT in diagnosis of mesenteric fibromatosis (MF).Methods CT images of 6 patients with pathologically proved mesenteric fibromatosis were retrospectively analyzed.The imaging characteristics analysis in-cluded the number,size,density of the lesion,the degree and quality of enhancement,as well as the relationship with the surrounding tissues.Results Singular lesion located in the mesentery was found in all the 6 patients (100%).The size of all cases ranges from 2.0 cm to 8.5 cm and the mean diameter was 6.5 cm.CT scan showed 5 tumors were homogeneous (83.3%),while one tumor had mixed den-sity (1 6.7%).On contrast-enhanced CT images,5 cases showed mild enhancement (83.3%),while 1 case showed moderate en-hancement (1 6.7%).And 4 cases appeared as heterogeneous enhancement (66.7%).4 cases of lesions infiltrated the surrounding tissue(66.7%)and the peripheral intestines were compressed in 2 cases(33.3%).5 masses were surrounded by mesenteric vessels (83.3%).Conclusion MF has certain CT manifestations,especially when mesenteric vascular surrounded the lesion.CT can provide important information for the diagnosis of this disease.

Objective To evaluate prognostic significance of early lactate clearance rate for cardiogenic shock patients on extracorporeal membrane oxygenation(ECMO).Methods Forty-seven patients with cardiogenic shock supported by venoarterial ECMO were prospectively enrolled from May 2010 to May 2013.Arterial blood lactate at pre-ECMO support(0 h),at post-ECMO 6 hours(6 h) were measured and then 6 h lactate clearance rate was calculated.90 days after admission was the endpoint of research.Patients were divided into the survival group(n =25) and the death group(n =22).6 h lactate clearance rate was compared between groups.The 6 h lactate clearance rate for predicting death was evaluated by receiver operating characteristic(ROC) curves.The surviving curve was drawn using the Kaplan-Meier method,and the survival of the patients was analyzed by the Log-rank test.Factors influencing the prognosis were analyzed by applying the multiplelogistic regression analysis.Results The 6 h lactate clearance rate was higher in survivors than in nonsurvivors [(38.6 ± 15.1) ％ vs.(14.4 ± 13.8) ％,P ＜ 0.05].The area under the ROC curve of 6 h lactate clearance rate for predicting death was 0.869 ± 0.075 (95％ CI:0.753-0.991).The best cutoff point was 20.0％ with a sensitivity of 92.0％ and specificity of 85.0％.KaplanMeier survival analysis showed that 90 days survival rate of high lactate clearance rate group and low lactate clearance rate group were 66.7％ and 35.0％,with significant difference between the two groups(Log-rank test,P ＜ 0.05).Multivariate logistic regression analysis showed that 6 h lactate clearance rate (OR =3.156,95 ％ CI:2.326-7.253,P ＜ 0.05) was one of the independent risk factors associated with mortality of patients on ECMO.Conclusion Early lactate clearance rate could be used as an important maker for evaluating the prognosis of cardiogenic shock patients on ECMO.

Humans ; Medicine ; Medicine, Chinese Traditional ; methods

OBJECTIVETo research the clinical application of lower cervical pedicle screw fixation procedure.

METHODSFrom September 2011 to July 2013,32 patients underwent posterior pedicle screw-rod system fixation were retrospective analyzed includinig 20 males and 12 females with an average age of 56.4 years old ranging from 21 to 78 years. Among them, 10 patients were traumatic cervical spinal injury, 9 patients were cervical spinal canal tumors, 7 cases were posterior longitudinal ligament ossification of cervical vertebrae, 6 cases were multiple segmental cervical spondylopathy. Preoperatively, X-ray, computed tomography, magnetic resonance imaging and magnetic resonance angiography of the vertebral artery were performed in all patients. After the operation and during the follow-up,X-ray and computed tomography were performed to confirm the pedicle screw position. The accuracy of the pedicle screw placement was evaluated by 4 grades classification from Lee. The spinal cord function was assessed by ASIA impairment scale for traumatic patients and JOA score for non traumatic patients.

RESULTSTotally 144 pedicle screws performed on 32 patients from C3 to C7 involving 132 screws of grade 0,5 screws of grade 1,5 of screws grade 2 and 2 screws of grade 3 according to postoperative CT. There were 12 screws penetrating the pedicle cortex including 8 screws at lateral,2 screws at caudal, 1 screw at medial and 1 screw at cranial. The follow-up time was 12 to 33 months with an average of (21.0±1.5) months. The spinal cord function was not improved in 6 complete cervical spinal cord injury patients,but their paraplegic level descended 1 to 3 segments. Four incomplete cervical spinal cord injury patients' ASIA impairment scale was increased by 1 to 2 grades in average. The JOA score of 22 atraumatic patients increased from preoperative 11.5±0.8 to 15.9±0.6 of postoperative at 6 months (P<0.01). There were no screw loosening,screw pullout and screw-rod breakage.

CONCLUSIONThe lower cervical pedicle screw fixation can provide excellent 3D stability of the vertebral column. The operation risk and Complication could be minimized by adequate preoperative evaluation for appropriate cases and individual pedicle screw placement. It deserved the clinical expansion.

Adult ; Aged ; Cervical Vertebrae ; injuries ; surgery ; Female ; Humans ; Male ; Middle Aged ; Pedicle Screws ; Retrospective Studies ; Spinal Cord Injuries ; physiopathology ; surgery

In this paper, we expatiate the advance of Tricholoma matsutake including distributing, environment, pure culture, domesticating cultivation and artificial forcing breeding in the area of Changbai Mountain of China.