This paper introduces a new method which controls discharge energy accurately. It is achieved by calculating target voltage based on transthoracic impedance and accurately controlling charging voltage and discharge pulse width. A new defibrillator is designed and programmed using this method. The test results show that this method is valid and applicable to all kinds of external defibrillators.
Defibrillators ; standards ; Equipment Design

Objective To assess the clinical value of transcatheter arterial chemoembolization (TACE) together with radiofrequency ablation (RFA) and sorafenib in treating recurrent hepatocellular carcinoma (HCC) after surgery.Methods A total of 40 patients with recurrent HCC after surgery, who were encountered at authors' hospital during the period from December 2009 to May 2014, were collected. The patients were divided into the study group (n=20) receiving TACE combined with RFA and sorafenib and the control group (n=20) receiving TACE plus RFA. Within 7-10 days after TACE, RFA was carried out. In the study group, oral sorafenib therapy (400 mg, two times everyday) started at 4 days after TACE. Withdrawal of sorafenib would be ordered if drug resistance occurred. Each patient underwent TACE combined with RFA not less than two times. Results The median survival time of the study group and the control group was 31.0 months and 24.8 months respectively, and statistically significant difference existed between the two groups (P<0.05). The one-year, 2-year and 3-year survival rates of the study group were 85%, 70% and 50%respectively, while the one-year, 2-year and 3-year survival rates of the control group were 80%, 55% and 30% respectively; the differences between the two groups were not statistically significant (P>0.05). The progression free survival (PFS) time of the study group and the control group was 6.8 months and 5.7 months respectively, the difference between the two groups was statistically significant (P<0.05). Conclusion TACE combined with RFA and sorafenib can prolong the overall survival time and the progression free survival time of patients with recurrent HCC after surgery.

Objective To investigate the therapeutic effect of vascular pedicle bone graft and compound bone matrical gelatin (Co BMG) in treatment of nonunion of femoral neck fracture . Methods 28 cases of femoral neck fracture who had been treated with operation and traction and observed for 6 to 9 months suffered from nonunion. The 28 cases of nonunion were treated by vascular pedicle bone graft and compound bone matrical gelatin. The progress of bone healing, complications such as necrosis of femoral head, and joint function were followed up after operation. Results All the 28 cases healed. The function of joint was evaluated according to Jacobs criteria. It was excellent in 19 cases, fine in 7 cases, and poor in 2 cases. Conclusion The vascular pedicle bone graft combined with BMG is the effective choice for treatment of nonunion of femoral neck fracture in adolescents and adults, because it has the double effects of bone grafting and bone induction.

BACKGROUND: Our former studies have shown that bone marrow mesenchymal stem cells (BMMSCs) can be induced differentiation to vascular smooth muscle-like cells (VSMLCs) and vascular endothelium-like cells (VELCs), which are compatible with collagen-embedded polyglycolic acid scaffolds. OBJECTIVE: To investigate the possibility of constructing small diameter tissue-engineered blood vessels via subcutaneous implantation. METHODS: The cells-scaffold complex was produced by separately seeding VSMLCs and VELCs derived from BMMSCs on polyglycolic acid collagen scaffolds. The two layers were separated by ECMgel. The cells-scaffold complex was subcutaneous implanted into small diameter tissue-engineered blood vessels.RESULTS AND CONCLUSION: Histological analysis of the small diameter tissue-engineered blood vessel walls revealed a typical artery structure, which was similar to natural vessels. The tissue-engineered blood vessels were not broken down under a force of 26.6 kPa. Eight weeks after implantation, the Brdu-labeled seed cells were found in the three layers of the vessel walls. The results revealed that the subcutaneous tissue was a good bioreactor to construct small diameter tissue-engineered blood vessels.

Objective To evaluate the feasibility, safety, and efficacy of Y-shaped jogged stent in patients with malignant hilar biliary obstruction. Methods During the period of January 2010 to June 2015,We retrospectively reviewed 98 cases of malignant hilar biliary obstruction who were received implantation of biliary tract stent. 17 consecutive patients who were treated with Y-shaped jogged stent were identified (group A) during January 2012 to June 2015. Group A was carefully matched according to patients' age, sex, type of tumor, stage, type of biliary obstruction, level of bilirubin at diagnosis, presence of metastasis and treatment, and 17 patients who were underwent unilateral stent placement alone with PTCD were chosen as control group (group B). Patients' baseline characteristics, stenting strategy, complications, stent patency time and survival rates were analyzed, and continuous variables of the two groups were compared using Student's t-test. Categorical variables were analyzed using the Fisher exact test. Results Y-shaped jogged stent implantation group and control groups were closely matched in terms of patients' age, sex, type of tumor, stage, type of biliary obstruction, level of bilirubin at diagnosis, presence of metastasis and treatment ( P>0.05). The bilirubin decreased rate in the two groups was 88.2%and 53.0%respectively (P<0.05). The median time of stent patency after stent implantation was(7.3 ± 1.0)months and(5.7 ± 0.9) months respectively (χ2=4.04,P=0.044), and the median survival time was(9.1 ± 1.5)months and(7.2 ± 1.1)months (χ2=4.60,P=0.032), with significant difference according to Kaplan-Meier analysis. There were no severe complications such as massive hemorrhage, perforation, biliary fistula and severe pancreatitis, which were associated with stent implantation. Conclusions The application of Y-shaped jogged stent is safe, feasible and effective in patients with malignant hilar biliary obstruction. It can relieve the clinical symptoms of biliary obstruction effectively with prolongation of stent patency time and survival rate significantly.

Objective To explore the feasibility and effectiveness of channel-assisted spatium intermusculare approach interbody fusion for treating lumbar vertebra diseases.Methods A total of 81 patients with lumbar vertebra diseases were treated from June 2012 to December 2013,including 35 males and 46 females between 29 and 76 years old with an average age of 54.6.There were 36 cases of lumbar disc degeneration,10 cases of recurrence in situ after lumbar disc herniation surgery,6 cases of huge lumbar disc herniation,11 cases of lumbar disc herniation with spinal canal stenosis,5 cases of extreme lateral lumbar disc herniation and 13 cases of lumbar degenerative spondylolisthesis.There were 67 cases of single segment lesion and 14 cases of two segment lesions.Lesion sites contained L1,2 in 1 case,L3,4 in 4 cases,L4,5 in 50 cases,L5S1 in 12 cases,L3,4 and L4,5 in 8 cases,and L4,5 and L5S1 in 6 cases.Results The length of incision was 2.42±0.45 cm in cases of single segment lesion and 4.28±0.38 cm in cases of two segment lesions.The operation time was 96.00±21.53 minutes and intraoperative blood loss was 347.50± 241.62 ml.During the operation,one case suffered from dural laceration,cerebrospinal fluid leakage and ipsilateral nerve root injury.Two cases suffered from pedicle fractures.Eight cases experienced epidermal necrosis of the incision.One case had poor wound healing.Three cases suffered from nerve injury.A total of 76 patients were followed up for 12-30 months,averagely 20.5 months.Intervertebral height of lesion segments was apparently recovered after surgery,and maintained in good condition during the final follow-up.No significant difference in the changes of area and grade of multifidus was detected 12 months after surgery and before surgery.Except 4 cases,the remaining had interbody fusion with a fusion rate of 94.7％.The balance between the coronal plane and sagittal plane of the lumbar spine was evidently improved.Average Japanese Orthopaedic Association score increased from 12.66±1.88 points preoperatively to 26.4±1.92 points during the final follow-up,which showed significant differences.Conclusion The method of channel-assisted spatium intermusculare approach interbody fusion has some advantages for treating lumbar vertebra such as small incision,fewer traumas,less bleeding,fast recovery,and high fusion rate.However,there is a long time of operation in the early stage and high occurrence rate of complications.

Objective To evaluate the short-term efficacy, safety and effectiveness of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) combined with radioactive 125I seed implantation in treating advanced non-small-cell lung cancer (NSCLC). Methods A total of 48 patients with inoperable and EGFR mutation-positive advance NSCLC were included in this study. The patients were divided into study group (n = 26) and control group (n = 22). Patients in the study group were treated with EGFR-TKIs combined with radioactive 125I seed implantation; while patients in the control group only received EGFR-TKIs treatment, which was kept on until the disease progressed. The clinical efficacy, and the incidence of side effect as well as the survival rate were determined, and the results were compared between the two groups. Results Local disease control rate of the study group and the control group was 92.3% and 68.2%respectively, the difference was statistically significant (P= 0.033), while the effective rate was 76.9% and 54.5%respectively, the difference was not significant (P=0.101). Progression-free survival (PFS) time of the study group and the control group was 14.1 months and 9.7 months respectively (P< 0.05). The one-year survival rate of the study group and the control group was 80.8%and 63.6%respectively (P<0.05), and the median survival time was 26.9 months and 17.1 months respectively (P < 0.05). The major complication caused by radioactive 125I seed implantation was pneumothorax. Conclusion For EGFR mutation-positive advance NSCLC, EGFR-TKIs together with radioactive 125I seed implantation is a safe and effective treatment.Its short-term efficacy is superior to pure EGFR-TKIs therapy. At present, this combination therapy is a new alternative for the treatment of EGFR mutation-positive advance NSCLC.

Objective To analyze the clinical effect of minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) in combination with unilateral pedicle fixation on lumbar degenerative diseases in the elderly.Methods From June 2011 and June 2013,51 elderly patients with lumbar degenerative diseases who underwent MI-TLIF in combination with unilateral pedicle fixation,including 39 males and 12 females,aged from 60 to 72 years (average 65 years old),were included in this study.All the 51 cases had mono segmental lesion,including 11 cases with the lesion in L3.4,22 cases with the lesion in L4.5,and 18 cases with the lesion in L5-S1.The operation time,blood loss,postoperative drainage and complications were recorded.Postoperative outpatient follow-ups were conducted once every 2-3 months for all cases,and JOA scoring criteria (29 points) of lower back pain were adopted to evaluate the clinical effects.Thin-layer helical CT scanning reconstruction was applied to evaluate the fusion rate of bone grafting.X-ray film of lumbar vertebra AP & LAT was employed to evaluate the intervertebral space height,the internal fixation and the position of cage.Results The operation time ranged between 50-90 min with a mean value of 65 min; blood loss ranged between 80-180 ml (average 110 ml); and postoperative drainage volume ranged between 20-70 ml (average 40 ml).Healing phase I was achieved in 49 cases,while post-operative local cutaneous necrosis around the incision site occurred in 2 case and the wound healed well after wound dressing.Dural laceration without nerve root injury occurred in 2 cases.The follow up in 51 patients ranged between 18 24 months (average 20 months).In terms of JOA scoring,the preoperative score was (9.7± 1.6),the post operative score was (21.4 ± 1.4) 7 d after operation and the score was (25.4 ± 1.2) in the final follow up.During the final follow-up,35 cases were evaluated as excellent,11 cases as good and 5 cases as moderate,the excellent and good rate was 90.2％,and the fusion rate of bone grafting was 88.2％.The intervertebral space height ranged from (9.2±1.5) mm before operation to (11.2±1.3) rnm 7 d after operation,to (11.0±1.2) mm in the final follow-up.There were significant difference in intervertebral space height before and after operation (both P＜0.05),and no difference was found between 7d after operation and the final follow-up (P＞0.05).Looseness,fracture or cage displacement were not observed.Conclusions The clinical effect of MI-TLIF in combination with unilateral pedicle fixation on lumbar degenerative diseases in the elderly is satisfied.It has the advantages of high fusion rate,less trauma,quicker recoverer,higher cost effectiveness and convenience.However,the indications for operation should be restricted and the long-term curative effect remains to be studied in further clinical studies.

Objective To investigate the efficacy of modified 270°spinal canal decompression combined with one-stage pedicle screw fixation and vertebral reconstruction for severe thoracolumbar fractures.Methods A retrospective case-control study was made on 44 cases of severe thoracolumbar fractures treated from January 2009 to June 2014.There were 34 males and 10 females, with age range of 20-68 years (mean, 37.9 years).The injured vertebrae included T11/12 in one case, T12-L1 in 10, L1/2 in 21, L2/3 in nine and L3/4 in three.Injury type was all AO type B2.According to the American Spinal Injury Association (ASIA), neurological deficit was Grade A in three cases, Grade B in five, Grade C in 22, and Grade D in 14.Load sharing score (LSC) was 7-9 points (mean, 8.1 points), while the thoracolumbar injury classification and severity score (TLICS) was 7-9 points (mean, 8.2 points).According to the difference of surgical procedures, all cases were divided into traditional group (21 cases) and improved group (23 cases).The patients in traditional group were treated by 270° spinal canal decompression combined with one-stage pedicle screw fixation and vertebral reconstruction, and those in improved group were treated by modified 270°spinal canal decompression combined with one-stage pedicle screw fixation and vertebral reconstruction.Between-group differences were compared with regard to operation time, intraoperative blood loss, postoperative drainage, allogeneic blood transfusion, pain visual analogue scale (VAS) at postoperative 72 hours, Cobb angle, anterior vertebral height, spinal canal compromise, Denis score, work state, neurological function, bone graft fusion and complications.Results Duration of follow-up was (32.4±15.8)months (range, 12-60 months).No wound infection or deterioration of neurological function was found after operation.Operation time was (2.4±0.5)hours in traditional group, less than (2.8±0.6)hours in improved group (P<0.05), while there were no significant differences in intraoperative bleeding, postoperative draining and blood transfusion between the two groups (P>0.05).VAS was (3.2±0.9)points in traditional group and (3.3±0.9)points in improved group at postoperative 72 hours (P>0.05).Cobb angle, anterior vertebral height and spinal canal compromise in both groups obtained well recovery and maintained after operation (P<0.05), but the recovery of spinal canal compromise was better in improved group than traditional group [(2.1±1.8)% vs.(11.8±6.1)%] (P<0.05).Denis score and work state were similar between the two groups (P>0.05).At the last follow-up, ASIA Grade A was noted in three cases, Grade C in two, Grade D in 23, and Grade E in 16.Bone union was achieved in all cases, with no implant loosening or breakage observed.Thirteen cases in traditional group were found with residual bone fragments in the spinal canal after surgery, and two of them received revision surgery.Conclusions Either modified or traditional 270° spinal canal decompression combined with one-stage pedicle screw fixation and vertebral reconstruction can attain satisfactory clinical results in treatment of severe thoracolumbar fractures.However, the modified 270°spinal canal decompression can achieve more thorough decompression without reducing stability of the spine.

Objective To study the effects of endothelial nitric oxide synthase (eNOS) gene transfection on endothelial progenitor cells (EPCs) transplantation in the process of injured vascular endothelium repair. Methods EPCs were cultured and expanded in vitro. EPCs were transduced with pseudotyped retroviral vectors expressing eNOS gene (pMCV-eNOS-EPCs) or green fluorescent protein gene (pMCV-GFP-EPCs). EPCs with expressing eNOS, GFP or saline were injected respectively into rat injured artery model by tail vein injection after balloon injury and again 24 hours. 14 days after transplantation. eNOS expression in injured artery was detected by RT-PCR, western blot and immunohistochemical methods. The morphology of arterial intima and media was studied by optical microscopy and image analysis system. Results Compared with GFP-EPCs group and control group, the mRNA and protein of eNOS were obviously high expressed in eNOS-EPCs group. EPCs transplantation reduce lumen stenosis and inhibit neointimalhyperplasia (eNOS-EPCs group vs.control group, 0.58±0.05 vs. 1.56±0.21, P < 0.01;GFP-EPCs group vs. control group, 0.84±0.09 vs.1.56±0.21, P < 0.05). eNOS gene transfection could further enhance this anti-proliferative effects (eNOS-EPCs group vs. GFP-EPCsgroup,0.58±0.05 vs. 0.84±0.09, P < 0.05). Furthermore, eNOS modified EPCs could improve the endothelial function of injured vascular endothelium. Conclusions eNOS gene transfection could increase the anti-proliferative effect of EPCs transplantation on injured artery and obviously ameliorate endothelial function.