The biological principle of genetic code and genetic computation in natural selection is discussed and a new frame of genetic computation is proposed.

[Objective]To discuss incidence of nerve root stretch injury and threshold value of traction injury in lumbar interbody fusion from posterior rout approach. [Method]Totally patients were treated by lumbar interbody fusion performed with posterior approach using the safe nerve root retractor,the force of dragging nerve root and the retracting time were showed on the display device,while the latency and amplitude of the DSEP wave were measured with Keypoint to monitor the status of the neural function.JOA scores were followed up 10 days,1 month,3 months and 12 months after operation respectively.[Result]Nineteen cases occurred latency prolongation and wave amplitude digression during the operation,when the tensile strength to nerve root was(4.1? 0.45) N and accumulating strength was(42.89?2.96) N*min.The tensile force of aggravation groups exceed stable and improvement groups obviously,incidence of FBSS was higher than the other two groups.[Conclusion]Stretch injury of nerve root during operation is the main cause of earlier period FBSS after interbody fusion.Master single tensile force less than(4.1? 0.45) N or accumulating strength less than(42.89?2.96) N*min is presumed safety.

ObjectiveTo study the role of laparoscopic splenectomy (LS) using the anterior approach with sequential layered dissection. MethodsFrom December 2007 to July 2009, we performed 27 LS using the anterior approach with sequential layered dissection. The clinical data were retrospectively analyzed. ResultsThe range of splenic length was 8-20 cm. Accessory spleen was found in 6 patients (22.2%). The mean operative time was 125 mins. The mean intraoperative blood loss was 90 ml, and the mean postoperative stay was 5.5 days. ConclusionsLaparoscopic splenectomy using the anterior approach with sequential layered dissection could be carried out smoothly and rapidly. It reduced accidental injuries and shortened the operative time.

Objective To investigate the application value of perioperative enhanced recovery after surgery (ERAS) combined with laparoscopic common bile duct exploration (LCBDE) in the treatment of choledocholithiasis.Methods The clinical data of 84 patients with choledocholithiasis who were admitted to the Yijishan Hospital from January 2011 to December 2013 were prospectively analyzed.A single-blind,randomized,controlled study was performed in the 75 patients who were allocated into the control group and the enhanced recovery after surgery group (ERAS group) based on a random number table.All the patients underwent LCBDE,the patients in the control group received conventional perioperative management and the patients in the ERAS group received perioperative management according to enhanced recovery rehabilitation program.All the patients were followed up by outpatient interview till postoperative month 6.The clinical features,liver function and residual stones in the patients were observed.The operation time,postoperative complications,postoperative intestinal function recovery,duration of hospital stay and hospital expenses in the two groups were compared.Measurement data with normal distribution were presented as x ± s.Comparison between groups were evaluated with an independant sample t test.Count data were analyzed using the chi-square test.Results All the 75 eligible patients undergoing successful operation were randomly divided into the control group (35 patients) and the ERAS group (40 patients).The operation time and volume of intraoperative blood loss in the control group and the ERAS group were (185 ±46)minutes and (124 ±28)mL,(178 ±37) minutes and (114 ±32)mL,respectively,with no significant difference (t =0.729,1.431,P ＞ 0.05).There were 12,14 and 10 patients in the control group and 5,6 and 4 patients in the ERAS group with postoperative incision pain,vomit and infection,showing a significant difference (x2=5.054,5.966,4.241,P ＜ 0.05).The level of white blood cell,alanine aminotrausferase and direct bilirubin in the control group and in the ERAS group were (11.4 ± 3.5) × 109/L,(128 ± 33)U/L,(38 ±14) μmol/L and (10.6 ± 3.0) × 109/L,(135 ± 35) U/L,(44 ± 16) μmol/L at postoperative day 1,compared with (7.8 ±2.9) × 109/L,(48 ± 14) U/L,(21 ± 8) μmol/L and (6.9 ±2.1) × 109/L,(43 ± 13) U/L,(20 ±7) μmol/L in the 2 groups at postoperative day 4,respectively,showing no significant difference between the 2 groups (t =1.018,-0.872,-1.767,1.553,1.836,1.044,P ＞ 0.05).The postoperative first flatus day,time of food intake,time of postoperative infusion and duration of hospital stay were (42 ± 13)hour,(45 ±14) hours,(6.8 ±2.3)days and (11.3 ±4.5)days in the control group,and (35± 11)hours,(19 ±7)hours,(4.2 ± 1.8) days and (9.6 ± 2.4) days in the ERAS group,with a significant difference between the 2 groups (t =2.741,10.524,5.485,2.077,P ＜ 0.05).The total hospital expenses was (18 729 ± 3 127) yuan in the control group,which was significantly greater than (16 981 ±2 756) yuan in the ERAS group (t =2.574,P ＜ 0.05).The liver function of all the patients was recovered at the postoperative month 1.Four patients with residual stones in the 2 groups were detected by T-tube cholangiography,and were cured by removal of gallstones by choledochoscopy.There were no complications of the abdominal pain,jaundice and fever in all the patients till the end of follow-up.Conclusion ERAS combined with LCBDE for the treatment of choledocholithiasis is safe and feasible,with the advantages of low morbidity,quick recovery,short duration of hospital stay and less hospital expenses.

Objective: To evaluate the effect of barrier m em brane on guided bone regeneration(GBR) in alveolar cleft. Methods: The alveolar cleft of animal model was established in the maxilla in 10 rabbi ts. The artificial alveolar clefts were treated immediately with following mater ials respectively: (1) PLA+collagen+rhBMP-2 membrane, (2)PLA membrane, (3)colla ge membrane, (4) blank control. All the membranes were fixed by PLA pin and mini -titanium pin. The animals were sacrificed 2 weeks, 1,2,3 and 6 months after su rgery respectively. Samples were studied through macroscopic observation, X-rad iography, histomorphology and enzyme histochemistry analysis. Results: In the clefts covered with the 3 kinds of membrane more bone fromation wa s observed. The compound membrane of PLA+collagen+rhBMP-2 showed the best bone regeneration effects. Conclusion: The GBR technique can be used to repair the bone defect of alveolar cleft.

Objective To explore the surgical method, clinical result, biomechanical property, and surgical indication of treatment of thoracolumbar burst fractures with titanium mesh fusion device. Methods 22 patients with the thoracolumbar burst fracture and paralysis were treated by anterior decompression and spinal stability reconstruction with titanium mesh fusion device and a titanium plate. In this group, the fracture was at the 12th thoracic vertebra in 7 cases, the 1st lumbar in 14, and the 2nd lumbar in 1. According to Frankel’s classification, 4 cases were of Grade A, 6 of Grade B, and 12 of Grade C. 20 patients experienced the kyphosis deformity. The kyphosis angles varied from 12 to 29 degrees with a mean of 19.5 degrees. Results The period of postoperative follow up varied from 0.6 to 2 years with an average of 1.2 years. The neural function was improved for more than 1 grade. 15 cases could control urination after the surgery. The kyphosis angles were reduced to 3 to 8 degrees with a mean of 5 degrees. The complications caused by the implants were not found. Conclusions To treat the thoracolumbar burst fractures with paralysis, the compressive elements from anterior side of the spinal cord should be completely removed. Since the titanium mesh fusion device plus a plate can reconstruct the spinal stability that satisfies spinal biomechanical property, it presents important application value.

Objective To investigate the electrocardiographic characteristics and assess the efficiency of ra-diofrequency catheter ablation(RFCA) in ventricular arrhythmia arising from the aortic sinus of Valsalva. Methods Eighteen patients(6 males and 12 females)were selected to undergo RFCA for ventficular arrhythmia originating from the left aortic sinus of Valsava. All of them were symptomatic,but without evidence of structural heart disease. Activation mapping was performed in the endocardium of the aortic sinus of Valsalva,then ablation was performed at the site with the earliest ventricular wave in endocardium electrograms. At the same time, coronary and aortic angiog-raphy were performed to assess the anatomic relationship between the ventricular tachycardia (VT)/ventricular pre-mature contraction (VPC) origin and coronary arteries and aortic valve before the RF energy delivery. Results Eighteen patients were successfully managed, with no major complications related to the procedure. VT eliminated and VPC counts on 24-hour ECG monitoring decreased significantly after the ablation[18 474(12 399,26 812)/24h vs 4 (1,7)/24 h, Wilcoxon signed-rank test, P<0.05]. During a follow-up period of 6 monthes, there was no recur-rence. Conclusions Ventricular arrhythmia arising from the aortic sinus of Valsalva has specific electrocardiograph-ic characteristics, and it can be successfully and safely treated under the guidance of activation mapping.

Objective To compare the clinical efficacy between continuous and intermittent androgen deprivation in high risk prostate cancer.Methods Sixty-four patients with high risk prostate cancer were treated from January 2008 to April 2009,36 cases who accepted goserelin and bicalutamide were taken as intermittent hormonal therapy (intermittent treatment group),while 28 cases who accepted bilateral orchiectomy in addition to flutamide were regarded as continuous hormonal therapy (continuous treatment group).The comparison of tumor specific mortality,time of prostate specific antigen (PSA) to nadir,tine to PSA recurrence,serum testerone and quality of life score were assessed between the two groups.Results In continuous treatment group and intermittent treatment group,follow-up period was (26.4 ± 10.3) and (28.1 ± 8.7) months,the time of PSA to nadir was (3.8 ± 2.1 ) and (4.0 ± 3.6) months,the time to PSA recurrence was (20.1 ± 12.3) and (24.5 ± 14.6) months,respectively.There was no significant difference between the two groups.At the time of 18,24 and 30 months after therapy,serum testerone was 0.85,0.88,0.89 μg/L in continuous treatment group,while 1.21,1.36,1.48 μg/L in intermittent treatment group,respectively (P ＜ 0.05 ).Similarly,quality of life score was 38.7,40.5,39.8 scores in continuous treatment group,while 49.2,51.4,52.3 scores in intermittent treatment group at the time of 12,18 and 30 months after therapy,respectively (P ＜ 0.05 ).Conclusions Clinical efficacy could not been found between continuous and intermittent endocrinic therapy of prostate cancer.During intermittent,quality of life seems to be better and increases in accordance with serum testerone recurrence at given time.

BACKGROUND: Interlocking intramedullary nails(SliN)is frequently used to treat femoral fracture.Routine pulling and compression and postoperative motorization are important for fracture healing.To improve fracture healing rate has been focused using various factors.OBJECTIVE: To explore the biomechanical performance of static SliN in fixation of femoral fracture,and the effect on fracture healing.METHODS: A total of 8 pairs of femurs from adult cadavers immersed in formalin were used to prepare models of midpiece transverse fracture.The fracture was respectively fixed using static SliN,TiNi shape-memory sawtooth-arm embracing internal fixator(TiNi SMA),and dynamic compression plate(DCP).The anti-compression,anti-bending,and anti-torsion rigidity were measured,and the stress shielding rate was calculated.RESULTS AND CONCLUSION: SliN was similar to DCP group in anti-compression rigidity and anti-bending rigidity(P > 0.05),but the anti-torsion was lower than DCP group(P<0.05).Compared with TiNi SMA group,SliN displayed greater anti-compression rigidity and anti-bending rigidity(P<0.05),but similar anti-torsion(P > 0.05).SliN was similar to DCP group in stress shielding rate(P>0.05),but significantly greater than TiNi SMA group(P<0.01).The biomechanics of SliN was stable,but the stress shielding rate was high.Changing static interlocking into dynamic interlocking in time is necessary in clinic to promote fracture healing.

Objective To evaluate the effects of pacing in right ventricular septum (RVS) on hemodynamics among atrioventricular sequential dual chamber pacing Methods Twenty patients with high grade or complete atrioventricular block received permanent dual chamber pacemaker ( DDD ),were randomized into right ventricular septum pacing group (RVS)and right ventricular apex pacing group (RVA)according to the ventricular leads position.The QRS duration of the ECG,the left ventricular ejection (LVEF),the interventricular mechanical delay( IVMD )and the plasma levels of brain natriuretic peptide (BNP)were compared before and after operations.Results Compared with the preoperation,the mean QRS duration ( ( 187.00 ± 15.67 ) ms and (94.00 ±9.17 ) ms),the IV MD ( (43.20 ± 6.79 ) ms and ( 15.00 ± 4.08 ) ms ),the level of BNP ( ( 89.70 ± 8.30) ng/L and (40.00 ± 4.73 ) ng/L) increased( P ＜ 0.05 ) and LVEF decreased significantly ( (53.70 ± 1.34) % and (58.60 ±1.65 )% ,P ＜ 0.05 ) in RVA group,but didn't change in RVS group (P ＞ 0.05 ).After three months following up,the mean QRS duration and the IVMD in RVS group( (119.00 ±7.38 )ms,(19.00 ±4.59)ms) were shorter than that of RVA group( ( 187.00 ± 15.67) ms,(43.20 ± 6.79) ms) ( P ＜ 0.05 ),the LVEF was higher and the plasma level of BNP was lower than that of RVA group ( (57.00 ± 2.00) % and ( 53.70 ± 1.34) %,(44.20 ± 9.18 ) ng/Land ( 89.70 ±8.30) ng/L,P ＜0.05).Conclusions The RVS pacing could keep the normal ventricular activation sequence and biventricular contraction synchrony farthest without side effects on hemodynamics in comparison with the RVA pacing.The RVS pacing is more approaching physiological rhythm than the RVA pacing.