Objective To investigate the effect of chronic electrical stimulus (CES) of low frequency and physiological frequency on diaphragmatic subtype of myosin heavy chain (MHC) and mechanical characteristic in rabbits with emphysema. Methods The rabbit model of emphysema was made by inhaling papain of ultrasonic atomization once a week for 3 weeks in 30 adult Japanese rabbits, 6 receiving 10 Hz chronic low-frequency electrical stimulation, 6 receiving 40 Hz, 6 receiving 10 Hz plus 40 Hz. Another 6 emphysema rabbits and 6 normal rabbits served as control. The twitch tension (Pt), titanic tension (Po), time to peak tension (TPT), half-relaxation time (1/2Rt), fatigue index (FI) and fatigue recovery index (FRI) were measured and SDS-polyacrylamide gel electrophoresis was used to observe the changes in subtype of MHC in control group, emphysema group, CES groups respectively. Results ①Following chronic electrical stimulus of 40 Hz, 10 Hz, and (10+40) Hz, the relative contents of MHC were increased in diaphragmatic muscle of rabbits with emphysema. The percentage of MHC-I was significantly increased in the 10 Hz group, while that of MHC-I and MHC-IIa were significantly increased in the (10+40) Hz group. ②Following chronic electrical stimulation using 40 Hz and (10+40)Hz, diaphragmatic muscle Pt and Po were significantly increased in rabbits with emphysema, TPT and 1/2Rt were significantly reduced, and FI and FRI were significantly decreased (P

Objective To study the influence of spinal instability after lamina decompression in symptoms and progno?sis. Methods The 76 patients were followed up for a minimum of 4 more years. The patients were divided into instability group (n=27) and non-instability (n=49) group according to the X-ray result of the final follow-up. The visual analogue scale (VAS) score, JOA score and improvement rate were compared between two groups at preoperation, 3-month after operation and the final follow-up. Results There were no significant differences in gender, age and mean follow-up time between two groups. There were no significant differences in VAS and JOA scores before surgery, 3-month after surgery and final follow-up between two groups. Postoperative VAS score decreased and JOA score increased with the increase in follow-up time (P<0.05). There were no significant differences in improvement rate [(80.0±8.8)%vs (83.6±11.7)%] and improvement ratio [81.48%(22/27) vs 61.22%(30/49)] between two groups (P > 0.05). Conclusion Although some patients show instability even with lumbar spondylolisthesis after lamina decompression on radiograph,which is no correlation with improvement of symptoms. With appropriate indications, lamina decompression is a simple and effective surgical method,which also retains the spinal movement function.

Objective To evaluate the relationship between airway obstruction and peripheral arterial stiffness in elderly patients with chronic obstructive pulmonary disease (COPD).Methods Ninetyeight elderly patients with COPD were enrolled.The patients were divided into two groups according to forced expired volume in 1 second (FEV1) percentage of predicted (FEV1 ％):mild-moderate group (FEV1 ％ ≥ 50％,62 cases) and severe group (FEV1％ ＜ 50％,36 cases).The brachium-ankle pulse wave velocity (baPWV),body mass index (BMI),24 h average heart rate,blood level of lipid,fasting blood glucose,arterial partial pressure of oxygen (PaO2) and high sensitivity C reactive protein (hs-CRP) level were compared between two groups.Results Compared with mild-moderate group,the BMI in sever group was lower:(22.9 ± 4.3) kg/m2 vs.(25.4 ± 3.3) kg/m2,24 h average heart rate was higher:(77.5 ± 12.8) times/rmin vs.(70.7 ± 9.5) times/min,PaO2 was lower:(71.7 ± 13.1) mmHg (1 mmHg =0.133 kPa) vs.(84.5 ± 13.2) mmHg,and there were statistical differences (P ＜ 0.05).The baPWV in mild-moderate group was (18.9 ± 4.2) m/s,and in sever group was (21.8 ± 3.6) m/s,and there was statistical difference (P ＜ 0.05).The hs-CRP in miid-moderate group was (6.62 ± 4.57) mg/L,and in sever group was (3.38 ± 2.13) mg/L,and there was statistical difference (P＜ 0.05).Conclusions The morbidity of peripheral arterial stiffness is increased in elderly patients with COPD.Progression of peripheral arterial stiffness is related to the severity of airway obstruction.

Objective To investigate the effect of chronic low-frequency electrical stimulation on the structural and metabolic changes of diaphragm of emphysema rabbits.Methods The rabbit model of emphysema was made by papain-inhaling of ultrasonic atomization once a week for 3 weeks in 30 adult Japanese rabbits,6 receiving 10 Hz chronic low frequency electrical stimulation,6 receiving 40 Hz,and 6 receiving(10+40)Hz.Other 6 emphysema rabbits and 6 normal rabbits served as control.An enzyme chemical method was used to observe the changes in the enzyme activities of sarcoplasmic reticulum Ca2+-ATPase,succinate dehydrogenase(SDH)and the lactate dehydrogenase(LDH)and changes in MHC in control group,emphysema group,and emphysema+chronic low frequency electrical stimulation group.Results Following chronic electrical stimulation using 40 Hz,10 Hz,and(10+40)Hz,the relative contents of MHC were increased in the diaphragmatic muscle of rabbits with emphysema.The percentage of MHC-Ⅰ was significantly increased in the 10 Hz group,while that of MHC-Ⅱa was significantly increased in the(10+40)Hz group.Following chronic electrical stimulation using 40 Hz and(10+40)Hz,diaphragmatic muscle SR Ca2+-ATPase activity was increased in rabbits with emphysema(P

Objective To observe the effects of indole-3-carbinol on neointimal hyperplasia and restenosis of rat artery after balloon injury and the possible mechanisms.Methods Balloon dilation was used to establish the neointimal injury model of left carotid artery in rats.Twenty Sprague-Dawley rats were randomly divided into single balloon dilation group(control group)and balloon dilation followed by indole-3-carbinol therapy group(therapeutic group).After balloon dilation,indole-3-carbinol(12.5,25,50 mg/d)was applied to the rats for 7 days respectively.The rats were killed two weeks after balloon dilation and the injured vascular specimens were harvested for pathologic examination and immunohistochemical staining.Results ①The neointimal thickness,neointimal area in the therapeutic groups were significantly less than that of the control group(P

Based on a small-scale questionnaire survey, the study analyzed the dilemma of medical students in clinical training, discussing how young teachers should guide the students get out of the dilemma, including how to resolve the conflict between further study and career, acquire more practicing opportunity, improve their communication ability with patients, and value their lives finally.

Objective To analyze the clinical results and early complications of corpectomy and reconstruction with titanium mesh cage implantation and pedicle screw fixation via a single posterior approach for severe thoracic and lumbar fractures.Methods Forty-four patients treated by reconstruction with titanium mesh cage implantation and pedicle screw fixation via a single posterior were studied retrospectively.There were 35 males and 9 females,with an average age of 37.3 years(range,19-66 years).The injury segments include 1 case at T11,5 cases at T12,20 cases at L1,11 cases at L2,5 cases at L3 and 2 cases at L4.According to AO classification,there were 24 cases of A3,17 cases of B1 and B2,and 3 cases of C1.According to ASIA,there were 10 cases of grade A,17 cases of grade B,10 cases of grade C and 7 cases of grade D.The neurologic function and effectiveness of correction of preoperative,immediate postoperative and 2years follow-up were compared,and the clinical outcome and early complications were analyzed.Results The follow-up time was 24 to 58 months,mean 38.9 months.At the time of 2 years postoperation,43 cases of incomplete neurologic deficit had improved 1 or 2 ASIA grades except 1 case of grade A.The results of decompression and reduction were satisfactory from the postoperative radiographic examinations.The correction maintained well and the implant loosening was not seen in 43 cases(97.7%)at the last follow-up.The com plications include:excessive blood loss(＞1500 ml)in 9 cases,transient nerve root injury in 4,cerebrospinal fluid leakage in 3,instrumentation failure in 1,mesh cage malposition in 3,iatrogenic leaving of free bone granula into the canal in 2,and superficial infection in 1.Conclusion This technique is effective for decompression and fusion,less invasive than combined anteroposterior procedure,and may be another good alternative for the treatment of severe thoracic and lumbar fractures.The early complications are not rare,but most of them are not serious and are relative to techniques.

Insulin secretion and insulin resistance were evaluated in 152 subjects with normal glucose tolerance, impaired fasting glucose (IFG) and (or) impaired glucose tolerance (IGT). The data showed that subjects with IGT exhibited an evident deficit in the early and late phases of insulin secretion after glucose load and mild insulin resistance, and subjects with IFG demostrated evident insulin resistant and a great decline in early phase insulin response and HOMA-β.

Objective To explore the viscoelasticity of relaxed myocardium in vivo through indentation method with an intervention ultrasound indentation system (IUIS). Methods Old myocardial infarction (OMI) models of canine were established by ligating left anterior descending branch of coronary artery for 3 months. The indentation creep tests were used respectively in OMI group and shame group (n=8, each) by IUIS in middle and advanced diastole stage in vivo. Test data were processed with three-parameter solid viscoelasticity model, and the viscoelastic parameters, such as instantaneous elastic modulus (E1), relaxation modulus (E∞), creep elastic modulus (E2) and viscous damping coefficient (η) in normal and infarcted myocardium were obtained and compared. Results All the parameters of E1, E∞, E2 and η increased obviously in OMI group than in sham group shown as follows: 27.81±6.74kPa vs. 6.78±2.43kPa; 17.87±3.59kPa vs. 4.52±1.56kPa; 49.54±14.35kPa vs. 16.82±12.37kPa and 1.97±0.78Pa.s vs. 0.66±0.40Pa.s. The differences were statistically significant (P<0.05). Conclusions IUIS is a feasible method to assess the viscoelasticity of relaxed myocardium in vivo. Three-parameter viscoelasticity model can be used to describe creep properties of relaxed myocardium. Both elastic modulus and viscosity resistance have increased in infarcted myocardium.

Objective To analyze the therapeutic effect of noninvasive mechanical ventilation in chronic obstructive pulmonary disease (COPD) patients with respiratory failure.Methods Sixty patients with COPD respiratory failure were randomly divided into two groups.30 cases in the conventional treatment group used conventional comprehensive therapy.30 cases in the nonfinvasive mechanical ventilation group were given noninvasive mechanical ventilation based on conventional treatment.The total effective rate,time to correct the abnormal breathing,hospitalization time were compared between the two groups.Before and after treatment,the arterial blood gas analysis indicators and heart rate,respiratory rate,probability,mortality for ventilator ventilation were compared in the two groups.Results The total effective rate of the noninvasive mechanical ventilation group was 96.67％,which was higher than 73.33％ of the conventional treatment group(x2 =6.405,P ＜ 0.05).The time to correct the abnormal breathing,hospitalization time of noninvasive mechanical ventilation group were (5.51 ± 1.41) d,(9.51 ± 2.13) d,respectively,which were shorter than (9.39 ± 2.56) d,(12.99 ± 3.57) d of the conventional treatment group (t =8.223,9.633,all P ＜ 0.05).Before treatment,the arterial blood gas analysis parameters and heart rate had no statistically significant differences between the two groups (all P ＞ 0.05).After treatment,the frequency of PaCO2,PaO2,heart rate and respiratory rate in the conventional treatment group were (60.45 ± 3.94)mmHg,(60.24 ± 4.12)mmHg,(92.58 ± 0.61)times/min,(22.45 ± 3.14)times/min,respectively,which in the noninvasive mechanical ventilation group were (52.24 ± 1.23) mmHg,(76.24 ± 5.26) mmHg,(83.92 ± 0.62) times/min,(17.26 ± 2.23) times/min,respectively,the differences between the two groups were statistically significant(t =5.133,3.734,5.166,6.360,all P ＜ 0.05).The invasive rate of invasive ventilator and mortality of noninvasive mechanical ventilation group were 3.33％ and 0.00％,respectively,which were lower than 20.00％,13.33％ of the conventional treatment group (x2 =7.214,6.247,all P ＜ 0.05).Conclusion Noninvasive mechanical ventilation is effective in treatment of patients with COPD respiratory failure,which can effectively improve the indicators of arterial blood gas and heart rate and respiratory rate,improve the prognosis of patients,improve the ventilation probability of invasive ventilator.