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Objective To observe the effect of different explosion impulse on rabbit lung injury and decide the death curve,so as to provide a reference for the prediction of lung injury.Methods Six healthy male New Zealand white rabbits with weight of 2.0-2.5 kg and age of (6 ± 1)months were selected.The rabbits were put 0.5 m,0.6 m,0.7 m,0.9 m,1.0 m,and 1.2 m away from 90 g TNT to carry out the blast injury experiment.The characteristic parameters of blast shock wave and general lung injury were recorded.Based on the experimental results combined with theoretical analysis,the changes of rabbit lung injury depending on the explosion distance as well as the rabbit death curve were determined.Results After the 90 g TNT explosion,the peak overpressure of shock wave and the corresponding specific impulse decreased quickly with the increase of explosion distance.The peak overpressure was 0.79 MPa and the specific impulse was 82 Pa · s at the explosion distance of 0.5 m.The peak overpressure was 0.1 MPa and the specific impulse was 34 Pa · s at the explosion distance of 1.2 m.The rabbits at 0.5 m and 0.6 m died,the rabbit at 0.7 m was severely injured,and the rabbits at 0.9 m,1.0 m,and 1.2 m were slightly injured.The dependence of lung injury degree on the explosion distance under 90 g TNT explosion was established based on dimensional analysis theory.The lung injury degree was exponentially attenuated with the explosion distance:φ =(R/0.6)-5.64(φ represented lung injury degree,and R represented the explosion distance).Considering the combined injury effects of peak overpressure of shock wave and its specific impulse on rabbit lung,the death curve of rabbit was determined:(p-0.1) (I-59) =2.6 (p represented peak overpressure,and I represented specific impulse).The criterion of "overpressure-specific impulse" was used to estimate the death of rabbit,and the death curve of rabbit was determined as (p-0.1)(I-59) =2.6(p represented peak overpressure and I represented specific impulse).The critical overpressure was 0.1 MPa and the critical specific impulse was 59 Pa · s.Conclusions Under the explosion condition of 90 g TNT,the relationship between degree of lung injury in rabbits and explosion distance is established.Death curve of rabbits is determined based on the damage effect of shock wave peak overpressure and specific impulse on the lungs of rabbits,which is significant for predicting the blast injury.
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Objective To compare the effects of preserving the posterior ligament complex (PLC) with torque loading and displacement loading on the biomechanical properties of the adjacent segments after lumbar decompression and fusion. Methods Six fresh male cadaver lumbar specimens of T12-S2 were tested in the sequence of intact, L4-5 laminotomy (preserving the PLC) with fixation and L4-5 laminectomy (destructing the PLC) with fixation, by applying both displacement loading and torque loading, respectively. Ranges-of-motions (ROMs) of the adjacent segments were measured under a noncontact photographic recording system. Results In displacement-loading mode, the flexion ROM in laminectomy group was significantly higher than that in laminotomy group, and no obvious ROM differences were found in the laminectomy and laminotomy groups under extension, lateral bending, and rotation movement. Conclusions Torque loading and displacement loading have different biomechanical effects on the adjacent segments after lumbar decompression and fusion. Compared with the laminotomy method, in which the PLC is preserved, the laminectomy method in which PLC structures are damaged can obviously lead to an increment of flexion ROMs at the adjacent segments, and also increase the ROMs of the adjacent segments under extension, lateral bending, and rotation movements, which might increase the risk of further instability of the fused adjacent segments.
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Intervertebral disc degeneration (IVDD) takes great affection on people health all over the world.With the extension of human life and aging,the number of sick people will grow rapidly.At present,both conservative and surgical treatment can only alleviate the symptoms,rather than the fundamental treatment for the process of degeneration.Therefore,the application of cell therapy in the treatment of degenerative disc regeneration is an innovative treatment.However,it's a great bottleneck for exogenous transplanted stem cells to survive in degenerated intervertebral disc with harsh environment containing strong force,acidic pH,hypoxia,hyperosmolarity and limited nutrition.In recent years,tissue endogenous repair has been demonstrated to be present in almost all human tissues,and endogenous stem cell play an important role in the process.Similarly,nucleus pulposus was also confirmed the existence of such a kind of tissue specific stem cells-nucleus pulposus derived stem cells (NPSCs)-a new promising candidate for the treatment of IVDD.NPSCs,as a new kind of stem cells,hold either the characteristic of stem cell and the special potential of themselves,such as the nice adaption of the environment in intervertebral disc and the superior potential of cartilage differentiation.Nonetheless,the isolations of NPSCs were different;cell phenotypes were lack of wildly acceptable standard and the biological characteristics were various among different NP sources.In addition,whether the application of NPSCs could be used in nucleus pulposus tissue engineering still calls for further research.Due to the unclear in degeneration mechanism of IVDD,the study on degeneration mechanism of NPSCs may play a great important role in clarifying this issue.
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This retrospective observational study aims to explore the treatment procedure and outcomes of arthroscopically assisted radiotherapy for diffuse pigmented villonodular synovitis [PVNS] of the knee joint. From September 2006 to August 2011, 28 diffuse PVNS patients were diagnosed and treated under arthroscopy. Twenty six underwent post-operative radiotherapy. All patients were followed up, and the average follow-up period was 54 months [range: 24 to 72 months]. All 26 patients who received external radiotherapy showed no recurrence at post-operative follow-up; The Lysholm knee joint function score increased from 54.3 +/- 9.0 at pre-operation to 71.2 +/- 6.7 at post-operation [paired t-test, t = -13.35, P<0.01]. Arthroscopic synovectomy is an ideal treatment for PVNS of the knee. Adjuvant post-operative external radiotherapy prevents the recurrence of diffuse PVNS
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A finite element model of cervical spine was three-dimensionally reconstructed through computed tomography (CT) scan, recording the edges of image using Snigraphics V18.0 software, and calibrating in sequence of point, line, area, and solid. The stress distribution of cervical C_(3-4) was analyzed using compute aided design to validate the availability of reconstructed models. Results showed that the three-dimensional finite element cervical C_(3-4) was feasible in simulation analysis. These indicate that the established three-dimensional finite element models can simulate biomechanical experiments, providing foundations for analyzing biomechanical performance of local structure of this finite element model under various pressure conditions.
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0.05).The operating time in group A was 106?22.3 min,94.1?29.3 min in group B and 81.6?22.3 min in group C.There were no significant differences between group A and B,or between group B and group C,but there was significant difference(P=0.009) between group A and group C.The was Two cases of dura tear occurred at operatiom and one case was converted to open discectomy in group A.There were three cases of reoperation in group B.There were no intra-and postoperation complications in group C.[Conclusion]From the learning curve of lumbar microendoscopic discectomy,surgeons can master such skill only after performing 30 or more cases of lumbar microendoscopic disecetomy.
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[Objective]To investigate the clinical and histopathological characteristics of myofibrosarcoma,and study its treatment and prognosis.[Method]The clinical features,histopathological characteristics,diagnosis,treatment and prognosis of two rare myofibrosarcoma patients were observed,and relative literatures were reviewed.[Result]After biopsy,the frist patient was treated with amputation in her middle thigh.postoperative chemotherapy was performed in the local hospital,but the drug and its dose didn't know in detail.one year latter,the patient died because of lung metastasis.The second patient was treated with tumor resection,but three months latter,the tumor recurred and was resected again,and the patient accepted chemotherapy,eleven nonthns latter,lung metastasis was found.then the patient died.About 54 patients with myofibrosarcoma were found in the literatures published in recent years.This neoplasms often involved the head and neck region,trunk and extremities in male patient A expandable and painless mass is the chief clinical features.Myofibrosarcoma can be identified by its specific morphologic features and positive myoid markers.[Conclusion]Myofibrosarcoma is a rare spindle cell neoplasm,Its morbidity dosen't know in detail.When making diagnisis,it is important to distinguished from synovial sarcoma,fibrosarcoma and leiomyosarcoma et al,Surgical resection is the mainstay of therapy,but the result of chemotherapy is not affirmed,The tumor is lower grade malignant one,and is invadable.The rate of local recurrence is high,and distant metastasis could be found.Its prognosis is not affirmed.
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Objective To analyze the reasons and therapeutic effects for revision of spinal fractures.Method Ninteen patients with revised internal fixation on spinal fractures were reviewed in average of 3.5 years follow-up. Neurological function, pain and daily life quality of patients with revision surgery were evaluated by questionnaire.ResultIncomplete spinal canal decompression as well as improper application of instrumentation were the main reasons of failed internal fixation for spinal fractures.All patients with incomplete spinal cord injury had improvement on neurological function to some extent after re-operation, and 17 of 19 patients (89%) indicated improved daily life quality. However, revision surgery failed to have motor recovery in patients with complete spinal cord injury.ConclusionCorrect surgical technique and selection of internal fixation are very important in the treatment of spinal cord injury.
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BACKGROUND: At present, genetic recombinant technique has been utilized to express recombinant human bone morphogenetic protein-2 (rhBMP-2)and to induce either orthotopic or ectopic regenerated bone successfully. But,because that osteoblastic activity induced by rhBMP-2 is lower than that by natural BMP-2, the perfect vectors have not been discovered yet.OBJECTIVE: BMP recombinant adenovirus (rAdV) was constructed so as to provide feasible vector for the basic treatment of bone defect.DESIGN: Single sample was designed in the experiment.SETTING: Experimental Center of Molecular Biology in First Hospital of Xi'an Jiaotong University.MATERIALS: PACCMV-PLPA plasmid, PJM17 plasmid, 293-cell line.METHODS: The experiment was performed in Experimental Center of Molecular Biology in First Hospital of Xi'an Jiaotong University from September 2001 to June 2002. Reverse Transcription-Polymerase Chain Reaction (RT-PCR) was used to clone the whole-length gene of BMP-2 and construct AdV vector. DNA-calcium phosphate coprecipitation was used to transfect accessory plasmid PJM17 into 293cell and homologous recombination was used to construct rAdV. The titer was assayed and CsC1 density gradient centrifugation and purification were applied.construction of rAdV.binant plasmid is named as pGEM-T/hBMP2, (3 015+1 213)bp in size.It was indicated in agar gel electrophoresis that the practical value was in BMP2 shuttle plasmid: The plasmid was about 10 Kbp in size. Since PACCMV-PLPA plasmid multiclone sites belonged to PUC plasmid series,EcoR Ⅰ enzyme digestion was used to linerarizate recombinant plasmid,10 Kbp in size. 8.8 Kb and 1.2 Kbp visible fragments were obtained durtion of rAdV: PCR technique was used to identify rAdV. The target fragment 1.2Kbp that was amplified by BMP2 specific primer of the whole length was in conformity completely with the theoretic value.CONCLUSION: Successful construction of BMP2 rAdV lays a foundation for the feasible genetic treatment with vector of bone defect.
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Objective To investigate the biological effects of low intensity of pulsed ultrasound (LIPUS) on human periosteal cells and marrow stromal cells in vitro. Methods LIPUS of 30 mW/cm2 was used to stimulate the cultured human periosteal cells and marrow stromal cells for 5 min, 10 and 20 min per day, respectively, followed by the examination of cell proliferation and differentiation potential. Results Thymidine incorporation and total protein assay indicated that LIPUS had no significant effect on DNA and protein synthesis of the periosteal and marrow stromal cells, suggesting that LIPUS did not promote proliferation of these cells. However, ALP activity and osteocalcin secretion of the human periosteal cells were dramatically increased. Conclusion The results suggested that low intensity pulsed ultrasound stimulated periosteal cell proliferation and differentiation toward osteogenic lineage, this might contribute to the curing effect of low intensity pulsed ultrasound for fracture.
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Objective To evaluate the radical debridement and anterior spinal fusion with strut graft for the treatment of spinal tuberculosis. Methods There were 78 cases in this series, 36 males and 42 females. The age was from 15 to 72 years, the mean was 47 years. The involved vertebral bodies were at 2 segments in 29 patients, at 3 segments in 41 patients and at more than 4 segments in 8 patients. The kyphosis was 13～92 degrees with a mean of 34 degrees. Radical debridement and spinal fusion with strut graft were used in all patients. In addition, the spine was instrumented in 3 cases for further stabilization. Strut grafts consist of ribs in 22 cases, iliums in 44 cases, iliums and ribs in 12 cases. Results The period of follow up lasted from 1 to 16 years with a mean of 5.2 years. 98.7% of the patients have good results and 97.4%have solid bony fusion. The kyphosis deformity was 5～62 degrees, the mean was 22 degrees. Conclusion The present results show that the radical debridement and anterior fusion with strut graft was effective for restoring the local anatomical alignment and the stability with high rate of solid bony fusion and lower rate of postoperative low back pain.
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constrained plate group(P
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Objective:To investigate the morphology and growth kinetics of the cells derived from the adult normal and herniated nucleus pulposus tissues.Methods: The cells derived from the adult normal and herniated nucleus pulposus were cultured in vitro.Passage 1,3,5 cells were chosen for light microscope and electron microscope observation.The cell growth rate,MTT value,maximal growth density,cellular mitotic index,cloning efficiency,and other parameters were observed in normal and herniated nucleus pulposus and the results were compared.Results: Compared with adult normal nucleus pulposus cells,the cells isolated from herniated nucleus pulposus were irregularly arranged and lost polarization,with rough endoplasmic reticulum slightly dilated.Under the same cellular density and culture conditions,the growth rate of passage 1 cells from adult normal and herinated nucleus pulposus had no significant difference,but the differences of passage 3 cells(P(0.05);) those of passage 3 cells were respectively 6.96?0.19 and 5.48?0.22,0.154?0.018 and 0.110?0.009,(22.52?(2.16)‰) and((16.68?)(2.35)‰,) and(48.7?3.3)% and(40.7?2.5)%;and of passage 5 cells were respectively 2.42?0.13 and 0.98?(0.14,) 0.085?0.006 and 0.050?0.007,(15.61?1.96)‰ and(9.34?2.12)‰,and(40.2?2.3)% and(28.34?(2.9)%.) There were significant differences between the parameters of passage 3 and 5 cells(P