A total of 30 patients with degenerative disc disease underwent posterior lumbar interbody fusion (PLIF) using a B-twin expandable spinal spacer (ESS) at the Department of Orthopedics,First Hospital,Peking University between August 2005 and February 2008 and were retrospectively analyzed.These patients consisted of 14 males and 16 females and averaged 28-72 years old.PLIF was performed at L1/2 in 1 patient,at L2/3 in 1 patient,at L3/4 in 1 patient,at L4/5 in 14 patients,and at L5/S1 in 13 patients.Patients underwent PLIF using simple B-twin ESS (n=8,1 employing single spacer,and 7 a pair of spacers) or B-twin ESS combined with pedicle screw (n=22,17 employing single placer,and 5 a pair of placers).B-twin ESS with a diameter of 9.5-11.0 mm was used in 28 patients and with a diameter of 11.5-13.0 mm in 2 patients.Examinations were carried out before surgery,post surgery,and during follow-up.Clinical symptoms were assessed using a 29-point Japanese Orthopaedic Association (JOA) score rating system.Spinal dysfunction was evaluated using the Oswestry Disability Index (ODI).The intervertebral space height and slippage reduction were measured through X-ray images.Twenty-eight of thirty patients were averagely followed up for 9 months.The excellent and good rate of ODI was 97% post surgery and 100% during follow-up period.The excellent and good rate of JOA was 93% post surgery and 96% during follow-up period.The proportion of intervertebral space height in upper vertebra that averaged 0.29±0.09 before surgery increased to 0.44±0.09 post surgery and stabilized at 0.4±0.09 upon final follow-up.The slippage was 10%-60% of upper vertebra before surgery,0%-40% post surgery,and 0%-30% till final follow-up.No neurological impairment or infection was found.There was 1 patient suffering from dural tear for adherence during decompression,1 patient presenting implant subsidence into the endplate post surgery,and 1 patient exhibiting spacer fragmentation during follow-up period.All outcomes indicate that B-twin ESS is characterized by minimal invasion,short surgery time,and less neurostimulation and provides satisfactory postoperative and follow-up efficiency.Attention should be paid to selecting suitable spacer type according to preoperative and intraoperative measurements.There is a breakage possibility if the spacer is put on one side of the space.To avoid this,sufficient bone graft is essential and two spacers may be put in one vertebra space if necessary.

[Objective]To study the effect of repairing of rat peripheral nerve defect with engineering artificial nerve composed with Schwann cells and poly lactic glycoli aced(PLGA).[Method]Human Schwann cells were vaccinated into PLGA tube with polyglactin 910.Sixty SD rats were divided into 3 groups randomly with 20 rats in each one: group A,self-nerve graft;group B,Schwann cells artificial nerve;group C,pure PLGA.Evaluations of electrophysiological and histological examines were carried out 8 weeks ad 12 weeks after operation.[Result]The outcome of group B showed similar to group A in general and histological study,however it expressed slightly lower in electrophysiological study,muscle weight and nerve fiber quantity.Marked neuron could be found in spinal cord after group B had been traced.Large number of regeneration nerve fibers could be seen from electron microscope.[Conclusion]The tissue engineering artificial nerve composed with Schwann cells is able to repair 20 mm defects of peripheral nerve,and it has an approximate treatment effect to the self-nerve grafting.

【Objective】To evaluate the therapeutic effect of comprehensive therapy for supine and prone external rotationed ankle fracture.【Methods】Thirty-nine patients with supine and prone external rotationed ankle fracture were treated with manipulative reduction,plaster and splint fixation,functional exercises and steaming with herbal medicine decoction(mainly composed of Herba Lycopodii,Herba Speranskia tuberculatae,Caulis Spatholobi,Semen Persicae,Flos Carthami,Radix Angelicae Sinensis,Rhizoma Chuanxiong,Myrrha,Lignum Sappan,Rhizoma Drynariae,Radix Dipsaci,Radix Achyranthis Bidentatae,Ramulus Cinnamomi,etc.)【Results】X-ray film after reduction showed that apposition of fracture was good in 39 patients.The fixation time ranged from 6~11 weeks,averaged 8 weeks.The fracture union achieved in all of the patients,and the time for union was 53~84 days,averaged 58 days.The therapeutic effect in 39 patients was as follows:excellent in 28,good in 6,ordinary in 3,ineffective in 2 and the excellent and good rate being 87.2%.【Conclusion】A satisfactory effect can be achieved when applying proper reduction methods for different types of ankle fracture,and when adopting functional exercises and steaming with herbal medicine decoction.

Objective:To investigate the levels of parathyroid hormo ne -related protein(PTHrP) in mandibular condylar cartilage during mandible forwar d positioning in different seasons. Methods:64 SD rats were rand omly divided into four groups according to seasons. Orthodontic appliance was us ed in 32 rats for 12 hours each day in daytime for mandibular protrusion. 8 rats were sacrificed at each season time point.Condyle samples were processed for PT HrP detection by a two-site immunoradiometric assay (IRMA) method.Another 32 ra ts without treatment were used as the controls.Macroscopic and microscopic appro ach were applied to analyze the results. Results:The level of P THrP in mandibular condylar cartilage(MCC) in the group of orthodontic treatmen t was higher than that in the control group(P

The incidence of locally recurrent rectal cancer is about 10%. Most patients have serious symptoms after tumor recurrence, which seriously affects the quality of life and prognosis of patients. Although it is more difficult to perform reoperation, it is still the main method to treat local recurrence of rectal cancer. At present, the main methods of reoperation include transabdominal anterior resection, combined pelvic organ resection, combined pelvic organ resection, and sacral resection. Open surgery is the main method. In recent years, with the extensive development of laparoscopic technology, laparoscopic techniques have been tried at home and abroad to perform reoperations for locally recurrent rectal cancer, showing good short-term results. The authors systematically introduce the application of laparoscopic technology in the reoperation of locally recurrent rectal cancer based on relevant research advances at home and abroad, in order to explore its clinical application prospects and promotion value.

Objective: To establish a simple, stable and high success rate separation method of myocardial cells in New Zealand rabbits. Methods: Compared influence between perfusion speed of 50 r/min (8 ml/min) and 65 r/min (11 ml/min) of Langendorff perfusion device on cell separation during separation course of myocardial cells. Results: Compared with perfusion speed of 50 r/min, there was significant decrease in time to obtain cells [(33±9.10) min vs. (19.29±2.73) min], and significant increase in success rate (50% vs. 91%) and survival rate [(38.26±2.63) % vs. (85.71±2.21) %] by perfusion speed of 65 r/min, P<0.01 all. Conclusion: Perfusion speed is an important factor that affects acute separation of myocardial cells in New Zealand rabbits, and 65r/min perfusion speed may be more stable and successful to obtain single myocardial cell.

Objective To verify the performance of the ABI ViiA 7 Taqman HBV-DNA detecting system for confirming its sta-bility,accuracy and reliability.Methods According to the evaluation protocols of Clinical and Laboratory Standards Institute (CLSI),the performance of ABI ViiA 7 Taqman HBV-DNA detecting system was assessed in the aspects of precision,accuracy,lin-earity and comparability;the quantitative detection limit validation experiments was performed by diluting specimen until quantita-tive detection limit is lower than the lower limit of detection,and the detection results were compared with the quality target re-quirements and the analysis capability declared by manufacturers.Results The CV in within-run precision of this detection system was 1.485%,1.990% and 0.932% respectively;the total CV was 1.876%,3.361% and 1.891%,respectively;the maximum devia-tion of accuracy was -6.8%;the linear correlation coefficient was 0.998 3;the regression equation was Y =0.974 8X +0.050 7. The linear range was 1.00E2 - 2.00E8;the quantitative detection limit was 100 IU/mL;the comparability of ABIViiA7 and ABI7500:P =0.115,r2 =0.994,the linear regression equation was Y =0.987 2X +0.051 7.Conclusion The ABI ViiA 7 Taqman HBV-DNA detection system has excellent precision,accuracy,sensitivity and linearity and has a good correlation with ABI7500, which can be used for the detection of clinical specimens.

Objective To evaluate the clinical and imaging features of the sellar region lesions in children.Methods The clinical and imaging features of 112 cases with sellar region lesions were analyzed retrospectively,which were confirmed by pathology.Results 37 cases were craniopharyngiomas, which had two main symptoms of intracranial hypertension(57%)and diabetes insipidus(11%).On imaging it demonstrated as a calcified cystic tumor(81%).18 cases were gliomas, the main clinical feature of which was decreased visual acuity,13 of them were pilocytic astrocytoma, which manifested as a solid tumor with significantly enhancement(94%).16 cases were germ cell tumors,the main complaint was diabetes insipidus (75%),13 of them were germinoma, which showed iso-high density on CT and moderate enhancement after administration of contrast.And it showed high signal intensity on DWI.7 cases were hamartoma,86% patients of which showed gelasmus epilepsy,the imaging showed iso-signal masses with no enhacement in the hypothalamic papillary region.5 cases were LCH,80% of which had the complaint of diabetes insipidus,imaging findings manifested as thinkened pituitary stalk and loss of hyperintensity of posterior pituitary on T1WI.3 cases were pituitary tumors.23 cases were Rathke's cleft cysts,3 cases were arachnoid cyst.Most of the patients presented with headache.Conclusion The clinical and imaging features shows some specific features, which is helpful to improve the correct rate of diagnosis and provide the basis for further treatment.

Objective To investigate the expression of COX-2 and angiogenesis in colorectal carcinoma tissue.Methods The expressions of COX-2 and MVD of 88 cases of colorectal carcinoma and 20cases of control tissue were examined by immunohistochemical staining. Results Compared with normal control,positive expression rates of COX-2(3/20 vs 64/88),and CD34(7/20 vs 74/88)of colorectal carcinoma tissue increased significantly(P＜0.05).MVD in COX-2 positive expressed tissue(63.24-20.4)was higher than that in COX-2 negative expressed tissue(41.2±29.8)(P＜0.01).Conclusion COX-2 is overexpressed in colorectal carcinoma tissue,which may have a strong relationship with MVD.

Objective To evaluate the safety and effect of local resection of the duodenum for the treatment of gastrointestinal stromal tumors(GISTs). Methods In this study, 12 duodenal GIST cases in which tumors located more than 1.0 cm away from the major duodenal papilla, underwent simple local resection of the duodenum along with the tumors measuring at 4 cm in diameter or less. The clinical data were retrospectively analyzed. Results After simple local resection of the duodenum for GISTs, no stomal leak occurred and the margin was all negative. Pathologically tumors were all low risk grade. There was no recurrence during a follow-up of 9-38 months. Conclusions Local resection of the duodenum is safe and efficient in the treatment of duodenal GISTs should the tumors locat more than 1.0 cm away from the papilla.