OBJECTIVE To study the effect of frequency difference and intensity difference on mismatch negativity (MMN) change in normal persons. Emphatically to observe the effect on the latency and amplitude of normal people's MMN, as well as the threshold of the acoustic difference which may induce the MMN. METHODS Twenty-four adults were included in this study. Their thresholds of pure tone audiometry were within 20dBHL. The MMN were measured by using the Smart EP ( ear potentiometer provided by the company of Intelligent Hearing) and the rule of the change by the difference of frequency and intensity to the latency and amplitude of normal people’s MMN were studied. RESULTS Along with the decreasing of the difference of the frequency, the MMN latency prolonged gradually. The amplitude of the MMN decreased gradually as the decreasing of the intensity difference. CONCLUSION A stable MMN graph is an important indicator of objective physiological test with hearing distinguish.

Objective To observe the occurrence of cardiovascular adverse events in patients undergoing mechanical ventilation with dexmedetomidine sedation,and to evaluate its safety in intensive care unit (ICU).Methods A prospective randomized controlled trial was conducted.Adult critical patients undergoing mechanical ventilation over 48 hours admitted to ICU of Zigong First People's Hospital in Sichuan Province were enrolled.The patients were divided into dexmedetomidine group (Dex group) and midazolam group (Mid group) according to the randomise number generated by computer.The patients in both groups were given slow intravenous infusion of 0.05 mg/kg midazolam and 1-2 μg/kg fentanyl to induce anesthesia before tracheal intubation,followed by 0.06 mg· kg-1· h-1 midazolam and 20-50 μg· kg-1 · h-1 fentanyl or 0.1-0.2 μg· kg-1 · h-1 sufentanil for continuous intravenous pumping to maintain analgesia and sedation;on the next day,the patients in Dex group was given dexmedetomidine (with the initial dose of 0.4 μg· kg-1 · h-1,and maintenance dose of 0.1-0.7 μg· kg-1 · h-1),and midazolam was stopped half an hour later;the original sedation and analgesia plan remained unchanged in Mid group.The goal of sedation was to maintain a Richmond agitation-sedation scale (RASS) score of-2 to 1 or a Ramsay sedation score of 3 to 4;patients were given midazolam if obvious agitation occurred,in combination with propofol for sedation if necessary;wakeup test was performed every day.Observation endpoints included patients discharged from ICU,death or mechanical ventilation over 28 days.Occurrence of cardiovascular adverse events during sedation such as hypertension,hypotension,bradycardia,tachycardia and arrhythmia,dose of sedatives and analgesics,duration of mechanical ventilation,length of ICU stay and 28-day mortality were observed in two groups.Results A total of 383 patients were enrolled,with 190 patients in Dex group and 193 in Mid group.There was no statistically significant difference in general data such as gender,age,acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) score and predicted mortality between two groups.Doses of midazolam,propofol and fentanyl in Dex group were reduced as compared with those of Mid group,while the dose of sufentanil was similar in two groups.The Ramsay score and RASS score of Dex group were significantly reduced as compared with those of Mid group (3.34± 0.63 vs.3.95 ± 0.86,-1.33 ±0.87 vs.-1.98 ± 1.27,both P ＜ 0.01).Bradycardia was prominent in Dex group,which was observed in more than half of patients at the beginning of the treatment (1-2 hours),but the patients requiring isoprenaline treatment for heart rate lower than 50 bpm were less than that of Mid group (3.7％ vs.5.2％,x 2 =0.506,P =0.477).The incidences of hypotension (45.3％ vs.68.4％),tachycardia (16.3％ vs.33.7％) and arrhythmia (14.7％ vs.31.1％) in Dex group were significantly lower than those of Mid group (all P ＜ 0.01),and no other cardiovascular adverse events such as cardiac arrest,sinus arrest,hyperglycemia or hypoglycemia were observed in two groups.There was no statistically significant difference in duration of mechanical ventilation between Dex group and Mid group [days:5 (2,28) vs.4 (2,56),Z =-1.917,P =0.055],but compared with Mid group,the length of ICU stay in Dex group was significantly prolonged [days:9 (2,67) vs.6 (2,57),Z =-4.302,P =0.000],and the 28-day mortality in Dex group was significantly reduced (22.6％ vs.44.6％,x2 =20.610,P =0.000).Conclusion Long time dexmedetomidine sedation is safe in critical patients undergoing mechanical ventilation,which can significantly reduce cardiovascular adverse events except bradycardia,and lower the 28-day mortality.

Objective To evaluate clinical efficacy of treating femoral intertrochanteric and subtrochanteric fractures combined with femoral shaft fractures using anatomic locking plate.Methods From January 2009 to June 2011,we treated 72 cases of femoral intertrochanteric and subtrochanteric fractures combined with femoral shaft fractures using anatomic locking plate.Sixty-four cases were followed up.There were 50 males and 14 female,with an average age of 42.8 years (range,21-79).All patients suffered from closed femoral unilateral fractures.The interval between injury and surgery was 2 h-16 d (average,4.6 d).All patients were followed up at regular interval.During the follow-up period,clinical and radiographic data were recorded.The clinical efficacy was evaluated with Harris hip function score.Results The mean operative time was 65 min (range,45-120 min); the mean blood loss was 210 ml (range,50-650 ml).All patients began to walk with crutches 3-35 d after surgery.During the follow-up period,no infection,deep vein thrombosis,screwed cut-out and implant failure occurred in all patients.Coxa vara with shortening deformity was noted in 2 cases,solid bone union was found in all the cases.The mean time of fracture healing was 5.2 months (range,3.6-10.5 months).According to Harris hip score,45 cases were classified as excellent,14 as good and 5 as fair,with excellent and good rate being 92.19％ (59/64).Conclusion Anatomic locking plate fixation provides stable fixation,with a high union rate and a minimal complication rate in treatment of intertrochanteric and subtrochanteric fractures combined with femoral shaft fracture.

Objective To discuss and analyze effect of biotype common handle (short handle) prosthesis in treating aged patients with femoral intertrochanteric fracture.Methods A retrospective analysis was carried out on 321 patients,among which 280 (102 males and 178 females,at age of 72-98years,average 82.5 years) obtained follow-up.According to a new fracture classification method (Piansui Classification),the typeⅠ a fracture was found in 65 cases and type Ⅰ b in 215.Most patients were combined with medical diseases,and after related medical collaborative treatment,standard biotype common handle prosthesis (artificial bipolar femoral head) replacement was applied to all patients.Early rehabilitation exercise was performed postoperatively.Results All the 321 patients lived through perioperative period successively,with no death in hospitalization.Meanwhile,postoperative complications were all cured in hospitalization.The patients could take out-of-bed activity at 1-3 weeks after operation.All 280 patients could take care of themselves at 12-46 months (average 28 months) of follow-up.According to Harris score,the results were excellent in 129 cases,good in 121,fair in 22 and poor in eight,with excellence rate of 89.3％.Conclusion Biotype common handle artificial femoral head replacement is an effective method to allow early ambulation,reduce complications and improve quality of life in treatment of intertrochanteric fractures in the elderly.

Objective To investigate the stress distribution in a cemented femoral component in elderly patients with a partial marrow type Ⅰ intertrochanteric fractures and to compare differences in the stress distribution after a long-and short-stem prosthetic replacement.Methods Spiral CT images of right femur of the volunteer were obtained and processed with Mimics software and modeling software to reconstruct a three-dimensional model of the femur.Based on this,a three-dimensional physical model for partial marrow type Ⅰ intertrochanteric fractures,long-and short-stem femoral prostheses,and cement mantle was established.Subsequently,a three-dimensional finite element model of long-and short-stem prosthetic replacement for intertrochanteric fractures was established using the finite element analysis software,and biomechanical analysis was implemented for the model.Results No significant changes in stress distribution of the femur occurred after long-or short-stem prosthetic replacement.Stress on the femur still presented a gradual increase from the proximal end to the distal end,peaked at the lower 1/3 of the medial and lateral junction and then decreased at the end.A stress concentration zone formed in the medial and lateral end of cement-stem interface in short-stem prosthetic replacement.Besides,the maximum value of stress in the lateral interface reached 15.3 MPa,but without surpassing the fatigue strength of the bone cement.Whereas,a stress concentration zone formed in the distal medial and lateral part of cement-stem interface and the medial middle part of the interface in long-stem prosthetic replacement and the maximum value was also lower than the fatigue strength of bone cement.No significant stress concentration zones were found in the femoral calcar reconstructed using bone cement.Conclusions Cemented long-or short-stem prosthetic replacement achieves no significant alteration in stress distribution of the femur.Loosening probability of the cemented long-or short-stem prosthesis is almost the same,but the latter has advantages of shorter surgery time,minor trauma,and fewer complications and may be more suitable for treatment of the elderly patients with a partial marrow type Ⅰ intertrochanteric fractures.

ObjectiveTo screen out the two-component system associated with drug resistance of Mycobacterium tuberculosis by detecting the differential expression of two-component system regulator genes between multidrug resistant Mycobacterium tuberculosis strains and drug sensitive strains. MethodsTotal RNA of MTB was extracted from cultured MTB during the logarithmic phase in the 7H9 brook medium, and then its purity was identified. Reverse transcription was further completed. The expressing levels of TCS response regulators were quantified using SYBR Green I qRT-PCR, which aimed at finding the differential expressions between multidrug resistant strains and sensitive strains. Finally, all of differentially expressed TCS were screened out under the stress of INH, SM and LFA. Results Compared with sensitive strains,multidrug resistant strains of Rv0491, Rv3133c, Rv3143 and Rv3246c were up-regulated 1. 03, 7.11,3.48and 1.37 folds, respectively (t/t' =5. 623, -4. 196, -3. 559 and -3. 016, respectively, P ＜0. 01 ). The expressing level of other regulators had no statistical significance between muhidrug resistant strains and drug sensitive strains. Under the antibiotic pressure, the expression of Rv1027c, Rv3246c and Rv3143 showed significant changes compared with no antibiotic group. ConclusionRv3246c and Rv3143 may be associated with MTB drug resistance and the differentially expressed genes in multi-drug resistant strains may be used as potential drug targets against drug resistant tuberculosis.

Objective To purify native and recombinant heparin-binding hemagglutinin(HBHA)protein,and investigate the activity of HBHA polyclonal antibody against aggregation of Bacillus CalmetteGuerin(BCG)induced by HBHA.Methods After growing BCG to the stationary phase in the 7H9 liquid medium,the native HBHA protein(nHBHA)was obtained by CL-6B column chromatography.At the same time,the HBHA gene fragment was cloned and expressed by transforming Escherichia coli BL-21.Then the polyclonal antibody against rHBHA was prepared by immunizing rabbit.Different comcentration of the HBHA protein was added to the BCG liquid medium,and the aggregation of the BCG was observed.Then,add the HBHA protein that incubated with anti-HBHA antibodies to the BCG culture medium and observe the aggregation of BCG.Results The purity of native HBHA was 99% and the concentration was 1.016 mg/ml.The expressed product contained 36% of total somtic protein.After purified,the purity of the recombinant HBHA protein was 97.1% and the concentration was 10.98 mg/ml.Both the rHBHA and nHBHA could induce the aggregation of BCG.When then concentration of nHBHA is 0.2μg/ml,BCG could be induced to aggregate,while the rHBHA concentration is 2μg/ml could induce the aggregation.Both aggregations could be suppressed by the polyclonal antibody against rHBHA.Conclusions The native and recombinant HBHA are successfully obtained.It is proved that the rHBHA could induce the aggregation of BCG similar as nHBHA,and polyclonal antibody against rHBHA could also suppress the activity of nHBHA.It suggested that rHBHA could be further used in clinical diagnosis and vaccination.

BACKGROUND:Culture condition,isolation method and efficiency are different in reported human umbilical cord-derived mesenchymal stem cells,which lack of unified identification standards.Therefore,it is necessary to establish a high-efficiency and economical culture system for human umbilical cord-derived mesenchymal stem calls(hUCMSCs).OBJECTIVE:To isolate hUCMSCs and induced differentiate into adipocytes and osteblasts.METHODS:The hUCMSCs were isolated form human umbilical cord by tissue adherence and digested with collagenase.The morphology,proliferation and immunophenotype of the 3rd passage cells were analyzed,and then cells were induced to osteogenic and adipogenic differentiation in vitro.RESULTS AND CONCLUSION:The hUCMSCs isolated from human umbilical cord by tissue adherence and digested with collagenase could be cultured and proliferated in vitro.Flow cytometry analysis revealed that the hUCMSCs were positive for CD29 CD44,CD59,CD105,but were negative for CD40,CD86 and HLA-DR.These calls could be induced to differentiate into adipocytes and osteblasts under proper inducing conditions.The hUCMSCs retained the appearance and phenotype even after being expanded more than 40 passages in vitro.This confirmed that the existence of MSCs in human umbilical cord and they had the capacity of differentiating into adipocytes and osteblasts.

Objective:To optimize the extraction process of Huoxue-Sanyu effervescent tablets. Methods:The hydroxysafflor yellow A content, paeoniflorin and dry extract yield were used as the evaluation indexes, by using analytic hierarchy process (AHP) method, integrative graded indicators method combined with orthogonal test and back propagation (BP) artificial neural network. To optimize the technics parameters, such as the amount of water, extraction time and frequency.Results:Paeoniflorin and hydroxysafflor yellow A showed good linear relation in the range of 0.079 5-1.590 4 μg and 0.038 5-1.539 2 μg respectively, with the average recovery rates of 98.18% and 96.22%. RSD was 0.77% and 1.31% respectively. The optimum extraction technic was 9 times of water, 3 times of heating reflux extraction, and each extraction last for 1 hour. Conclusions:The optimized combined method of orthogonal experiment and BP artificial neural network is practical with high efficiency. The optimal extraction process is stable and reasonable.

Objective:To establish the TLC identification method and content determination method of ferulic acid, ligustilide, hydroxysafflor yellow A and paeoniflorin in Shangke Huoxue Decoction for quality evaluation.Methods:Ferulic acid, ligustilide, hydroxysafflor yellow A and paeoniflorin were qualitatively identified by TLC method, and the content was determined by HPLC method. Waters Symmetry ShieldTM RP18 column (4.6 mm×250 mm, 5 μm) was set, the mobile phase consisted of acetonitrile-0.15% phosphoric acid water with gradient elution at a flow of 1.0 ml/min, and the column temperature was 30 ℃.The detection wavelength was 320 nm (33-50 min for ferulic acid, 55-70 min for ligustilide), 403 nm (7-31 min for hydroxysafflor yellow A) and 230 nm (7-31 min for paeoniflorin).Results:The TLC spots were clear. The linear relationships of ferulic acid, ligustilide, and hydroxysafflor yellow A were good in the range of 3.05-48.74 μg, 3.50-26.24 μg, 21.34-213.44 μg. The method was stable, repeatable with good recovery rate.Conclusion:The TLC and HPLC method for the simutanous determination of the four effective components in Shangke Huoxue Decoction were established, and the methods are suitable for the quality evaluation of Shangke Huoxue Decoction.