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find Keyword "Dynamic" 60 results
  • DYNAMICCHANGE OF EPIDERMAL STEM CELLS IN THE WOUND HEALING COURSE OF DIABETIC RATS

    Objective To observe the epidermal width, the amount variation and distribution character of epidermal stem cells(ESCs) and the wound healing rate at different periods of diabetes mellitus(DM) rats after trauma, thento study the correlation of them. Methods Forty-eight Wistarrats were divided into DM group and normal control group randomly(n=24).TheDM rats were induced by streptozocin (STZ) and then made chronic healing wound by special perforex.At the 3rd, 4th, 7th,14th and 21st days after trauma, the healing rate was calculated, the wound edge and granulation tissue were obtained for haematoxylin-eosin (HE) staining and immunohistochemical staining of keratin 19(K19) and β1 integrin. Then the epidermal width, the area and the gradation value of positive unit(PU) were measured. Results At the 3rd, 7th,14th and 21st days after trauma, the wound healing rates of normal rats were 24.48%±3.37%, 50.46%±1.26%, 92.82%±2.12% and 99.41%±0.66% respectively, while those of DM rats were 2.43%±1.02%, 40.59%±1.65%, 80.77%±3.57% and 85.40%±0.94% respectively, showing significant differences (Plt;0.01). Before trauma, there was no significant difference in the epidermal width between normal rats and DM rats (Pgt;0.05). However, at the 3rd, 7th, 14th and 21st days after trauma, the epidermal widths of normal rats were 26.43±3.21, 33.29±3.52, 31.53±3.35 and 26.01±3.19 μm respectively, while those of DM rats were23.58±2.33, 31.02±3.38, 33.72±5.49 and 21.80±4.02 μm respectively,the epidermal widths in DM rats were significantly lower than those in normal rats(Plt;0.01). The average PU value of K19 in normal rats were 91.68%, 93.14%, 72.27% and 70.31% respectively, while those in DM rats were 40.29%, 40.79%, 29.94% and 10.37% respectively. The average PU value of β1 integrin in normal rats were 49.6%, 91.16%, 77.13% and 57.17% respectively, while those inDM rats were 38.94%, 24.16%, 61.36% and 38.83%. The results indicated that the average PU values of K19 and β1 integrin in DM rats were significantly lower than those in normal rats(Plt;0.05). Conclusion The amountand activity decrease of ESCs may be one of the important mechanisms of difficult recovering wounds of DM rats.

    Release date:2016-09-01 09:23 Export PDF Favorites Scan
  • Clinical characteristics of dynamic benign tracheobtonchial stenosis: two cases report

    Objective To improve the knowledge on dynamic benign central airway stenosis through two typical cases. Methods The clinical features, imaging findings, and bronchial morphologic changes of two cases characterized by dynamic benign central airway stenosis were retrospectively analyzed. The etiologies for the two cases were tracheobronchomalacia (TBM) and excessive dynamic airway collapse (EDAC), respectively. Results Central airway stenosis and reversible airway obstruction were common clinical characteristics for the two cases. However, there were identifiable differences on imaging findings and bronchial morphologic changes between the two cases. Multidetector computed tomography showed sabre-sheath trachea and narrowed trachea in coronal position for TBM, while small sized trachea in exhalation phase and narrowed trachea in sagittal position for EDAC. Bronchoscopy displayed narrowed airway, swelling mucosa, and the absence of annular cartilage for TBM, while crescent airway with membranacea part protruding to lumen in inspiration phase, and the integrity of annular cartilage for EDAC. Conclusion Multidetector computed tomography and bronchoscopy examinations are valid methods to distinguish TBM and EDAC, which are both characterized by dynamic benign central airway stenosis.

    Release date:2018-05-28 09:22 Export PDF Favorites Scan
  • A COMPARATIVE STUDY BETWEEN Coflex INTERSPINOUS DYNAMIC RECONSTRUCTION AND LUMBAR 360° FUSION IN TREATING SINGLE-LEVEL DEGENERATIVE LUMBAR SPINAL DISORDERS

    Objective To compare the effectiveness and radiological changes of posterior decompression combined with Coflex interspinous dynamic reconstruction or lumbar 360° fusion for degenerative lumbar spinal disorders at L4, 5. MethodsBetween October 2008 and November 2010, a comparative study was carried out on patients with degenerative lumbar spinal disorders at L4, 5. In group A, 29 patients underwent posterior decompression combined with Coflex interspinous dynamic reconstruction; there were 20 males and 9 females with an average age of 45.1 years (range, 21-67 years); and the disease duration was 2 months to 4 years. In group B, 31 patients underwent posterior decompression combined with lumbar 360° fusion treatment; there were 16 males and 15 females with an average age of 56.2 years (range, 32-86 years); and the disease duration was 3 months to 6 years. Except the age, there was no significant difference in gender, disease duration, and etiology etc. between 2 groups (P gt; 0.05). The results were assessed by Japanese Orthopaedic Association (JOA), visual analogue scale (VAS) scores, and Oswestry disabil ity index (ODI). The range of motion (ROM) and intervertebral height of affected and adjacent segments, and the ROM of lumbar were measured before operation and last follow-up. Results Significant differences were found in the operative time and blood loss between 2 groups (P lt; 0.05). Intraoperative dural tear occurred in 1 case of group B, spinal canal venous plexus hemorrhage in 1 case of group B, and postoperative cerebrospinal fluid leakage in 2 cases of group A and B respectively, showing no significant difference (χ2=0.119, P =0.731). The follow-up was 12-21 months in group A and was 12-23 months in group B. At the last follow-up, the JOA, VAS scores, and ODI of groups A and B were significantly improvedwhen compared with the preoperative values (P lt; 0.05). The VAS score of group A was significantly higher than that of group B (P lt; 0.05). There was no significant difference in the intervertebral height of L4, 5 and L5, S1 of groups A and B between pre- and post-operation (P gt; 0.05). In group B, the intervertebral height of L3, 4 was significantly reduced (P lt; 0.05) compared with the preoperative one. There was no significant difference in the ROM of L5, S1 and ROM of lumbar in groups A and B between preand post-operation (P gt; 0.05). At last follow-up, the ROM of L4, 5 was significantly reduced in group A (P lt; 0.05), and the ROM of L3, 4 was significantly increased in group B (P lt; 0.05). Except significant differences in the intervertebral height and ROM of L3, 4 between 2 groups (P lt; 0.05), no significant difference was found in other parameters (P gt; 0.05). Conclusion Posterior decompression combined with Coflex interspinous dynamic reconstruction has the same effectiveness as lumbar 360° fusion in treating degenerative lumbar spinal disorders at L4, 5, but the former has a protective effect on the adjacent segments of fusion and is recommended for initial treatment of young adults and the elderly and frail patients with recurrent.

    Release date:2016-08-31 05:44 Export PDF Favorites Scan
  • BIOMECHANICAL RESEARCH OF LESS INVASIVE STABILIZATION SYSTEM AND DYNAMIC CONDYLAR SCREW IN FIXING SUBTROCHANTERIC FRACTURES OF FEMUR

    Objective To compare the biomechanical characteristics of the less invasive stabilization system (LISS) and the dynamic condylar screw (DCS) in the fixation of subtrochanteric fractures of the femur so as to provide theoretical basis for choosing internal fixator in clinical application. Methods Twelve cadaveric human femurs (35-50 years old) were selected with similar proximal femur, excluding deformities, fractures, and other lesions. The twelve femur specimens were randomly divided into 2 groups, 6 specimens per group. An 1 cm gap of osteotomy model was made in the proximal femur up to 1 cm below the lesser trochanter to simulate a comminuted subtrochanteric fracture of femur, and the distal end was embedded with denture acrylic and liquid for denture acrylic. Fracture was fixed by LISS in group A, and was fixed by DCS in group B. The specimens were fixed on Instron-8874 servo-hydraulic mechanical testing machine in a single-leg standing position, and the axial compression test and dynamic fatigue test were carried out to compare the compressive strength and the strain distribution at both sides of the fracture line. Results Axial compression test: the strain values of the 2 strain gauges in group A were significantly smaller than those in group B (P lt; 0.01); the vertical down displacement of the femoral head in group A was significantly smaller than that in group B (P lt; 0.01) under the same load; when the load was 600 N, the axial rigidity of group A was (209.06 ± 18.63) N/mm, which was significantly higher than that of group B [(65.79 ± 7.26) N/mm] (t=3.787, P=0.004). Dynamic fatigue test: the vertical down displacement of the femoral head in group A was significantly smaller than that in group B in the same cyclic loading cycle (P lt; 0.01); when the vertical down displacement of the femoral head was 0.5 mm, the force and the cyclic loading cycles in group A were significantly larger than those in group B (P lt; 0.01). Conclusion LISS, which has good mechanical stability, can meet the requirements for subtrochanteric fracture of femur fixation in biomechanics and anatomical structures. It can be proven that the LISS internal fixator is firmer than the DCS internal fixator by biomechanical comparison.

    Release date:2016-08-31 04:21 Export PDF Favorites Scan
  • RESEARCH ADVANCE OF DYNAMIC HIP SCREW INTERNAL FIXATION IN TREATMENT OF INTERTROCHANTERIC FRACTURES

    Objective To investigate the development of dynamic hipscrew (DHS) internal fixation in the treatment of intertrochanteric femur fractures. Methods The latest relevant articles were reviewed extensively, including biomechanics and clinical application research. Results DHS is the effective selection for the treatment of intertrochanteric femur fractures, especially by the innovation of DHS structure, operative manipulation.Conclusion Treatment of intertrochanteric femur fractures with DHS is still a gold level, but strict selection of patients, proficiency operation and invasive manipulation are the most essential principles.

    Release date:2016-09-01 09:28 Export PDF Favorites Scan
  • RESEARCH ADVANCEMENT OF LUMBAR INTER-SPINOUS PROCESS NON-FUSION TECHNIQUES

    Objective To elucidate the new development, structural features and appl ication of the lumbar interspinous process non-fusion techniques. Methods With the review of the development course and important research works in the field of the lumbar inter-spinous process non-fusion techniques, the regularity summary, science induction, and prospect were carried out. Results The lumbar inter-spinous process non-fusion technique was a part of non-fusion insertof spinal division posterior surface. According to the design, it could be divided into two major categories: dynamic and static systems. The dynamic system included Coflex and device for intervertebral assisted motion; the static system included X-STOP, ExtenSure and Wall is. The lumbar inter-spinous process non-fusion technique was a new technique of spinal division, it could reserve the integrated function of intervertebral disc and zygapophysial joint, maintain or recover the segmental movement to a normal level, and have no adverse effect on the neighboring segments. A lot of basic and cl inical researches indicated that lumbar inter-spinous process insert had extensive appl ication to curatio retrogression lumbar spinal stenosis, discogenic low back pain, articular process syndrome, lumbar intervertebral disc protrusion and lumbar instabil ity and so on. Conclusion With the matures of lumbar inter-spinous process non-fusion techniques and the increased study of various types of internal fixation devices, it will greatly facil itate the development of treatment of lumbar degenerative disease. But long-term follow-up is needed to investigating the long-term efficacy and perfect operation indication.

    Release date:2016-08-31 05:47 Export PDF Favorites Scan
  • TREATMENTS OF GERIATRIC FEMORAL INTERTROCHANTERIC FRACTURES

    Objective To investigate the treatment method of senile patients with femoral intertrochanteric fractures and its cl inical outcomes. Methods From January 2005 to December 2007, 192 senile patients with femoral intertrochanteric fractures were treated, including 85 males and 107 females aged 65-92 years old (average 75 years old). The injury was causedby fall on walking in 106 cases, fall when riding a bicycle in 55 cases, and traffic accidents in 31 cases. According to Evans classification, there were 12 cases of type I A, 43 cases of type I B, 29 cases of type II, 24 cases of type III A, 23 cases of type III B, 26 cases of type IV, and 35 cases of type V. One hundred and fifty patients were associated with cardio-cerebrovascular diseases, 120 patients were compl icated with chronicle hypertension, 90 cases were associated with bronchitis, and 75 cases were compl icated with diabetes. The time from injury to hospital admission was 1 hour to 14 days. Among those patients, 108 were treated with conservative treatment, 68 received dynamic hip screw (DHS) fixation, and 16 underwent proximal femoral Gamma nail fixation. Results All the patients were followed up for 12-36 months (average 18 months). The fracture all reached bone union without occurrence of nonunion and delayed union. Patients could take care of themselves, and there were no occurrences of serious pains and dysfunctions. The therapeutic effect was satisfactory. The conservative treatment group: the average hospital stay length was 48 days; the average bone heal ing time was 14 weeks; 23 cases had different degrees of coxa adducta; Harris score system was adopted to evaluate hip joint function, 45 cases were graded as excellent, 31 as good, 10 as fair, and 22 as poor, and the excellent and good rate was 70.4%. DHS internal fixation group: the average operation time was 60 minutes; the average bleeding volume during operation was 200 mL, the average hospital stay length was 24 days; the average bone heal ing time after operation was 12 weeks; Harris score system was adopted to evaluate the injured hip joint function, 38 cases were graded as excellent, 21 as good, 8 as fair, and 1 as poor, and the excellent and good rate was 86.8%. Gamma nailfixation group: the average operation time was 70 minutes; the average bleeding volume during operation was 200 mL, the average hospital stay length was 14 days; the average bone heal ing time after operation was 12 weeks; Harris score system was adopted to evaluate the injured hip joint function, 11 cases were graded as excellent, 4 as good, 1 as fair, and the excellent and good rate was 93.8%. Conclusion For geriatric femoral intertrochanteric fractures, operative treatment should be performed, the preoperative preparation should be sufficient, and individual-oriented treatment method should be selected on the basis of physical conditions of patients and the types of fractures.

    Release date:2016-09-01 09:08 Export PDF Favorites Scan
  • A Blinding Comparative Study of Multiparametric Magnetic Resonance Imaging in Diagnosing Prostate Cancer

    ObjectiveTo compare the effectiveness of T2 weighted image (T2WI) and some compounded MRI techniques, including T2WI combined with magnetic resonance spectroscopy (T2WI+MRS), T2WI combined with diffusion weighted imaging (T2WI+DWI) and T2WI combined with dynamic contrast-enhancement [T2WI+(DCE-MRI)] respectively, with 1.5 T MR scanner in diagnosing prostate cancer through a blinding method. MethodsBetween March 2011 and April 2013, two observers diagnosed 59 cases with a blinding method. The research direction of radiologist A was to diagnose prostate cancer. The observers diagnosed and scored the cases with T2WI, T2WI+(DCE-MRI), T2WI+MRS, T2WI+DWI and compositive method respectively. The data were statistically analyzed with receiver operating characteristic (ROC) curve. ResultsAccording to the ROC curve, both observers got the sequence of area under curve (AUC) as T2WI+DWI > T2WI+(DCE-MRI) > T2WI+MRS > T2WI. On the basis of the result from observer A, the AUC from each technique was similar. The AUC of T2+DWI was slightly bigger than others. The specificity of single T2WI was the lowest; the sensitivity of T2WI was slightly higher. The AUC of the compositive method was marginally larger than T2WI+DWI. According to the result from observer B, the AUC of T2WI+DWI was obviously larger than the others. The AUC of single T2WI was much smaller than the other techniques. The single T2WI method had the lowest sensitivity and the highest specificity. The AUC of T2WI+DWI was slightly larger than the compositive method. The AUC of T2WI+(DCE-MRI), T2WI+MRS, single T2WI methods from observer A was obviously higher than those from the score of observer B. The AUC of T2WI+DWI from the two observers was similar. ConclusionThe method of combined T2WI and functional imaging sequences can improve the diagnosing specificity when a 1.5 T MR scanner is used. T2WI+DWI is the best method in diagnosing prostate cancer with least influence from the experience of observers in this research. The compositive method can improve the diagnosis of prostate cancer effectively, but when there are contradictions between different methods, the T2WI+DWI should be considered as a key factor.

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  • Standard Operating Procedure for Drug Labeling and Dynamic Medication Management of Double-blinded Randomized Controlled Trial

    Dynamic medication management can help to improve efficacy and save consumption in such trials when an investigational medication is expensive or in short supply or has a fairly short shelf-life in a long-lasting clinical trial, or, if protocol changes during study period. We presented the standard operating procedure of dynamic medication management and drug labeling through an instance of double-blind randomized controlled trial of Chinese Medicine for hepatopathy. Compared to conventional drug labeling, dynamic medication management and drug labeling is more flexibility to deal with problems during the study period, such as protocol update, medication waste, and outdated medication and so on. Appropriate method and reasonable procedure can ensure the precise implementation for drug labeling and medication management of double-blinded randomized controlled trials.

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  • Correlation Between Volume Dependence of Respiratory Mechanics and Dynamic Intrinsic Positive End-Expiratory Pressure in COPD Patients During Pressure Support Ventilation

    Objective To investigate the correlation between dynamic intrinsic positive endexpiratory pressure ( PEEPidyn) and volume dependence of elastance and resistance of respiratory system ( Evd/Rvd) derived from nonlinear analysis of respiratory mechanics in COPD patients during pressure support ventilation ( PSV) . Methods Twenty-five COPD patients mechanically ventilated using mode of PSV were ventilated at a PSV level of no less than 20 cm H2O in a period of 15 minutes to attain so-callednear-relaxation state. The pressure( P) , flow( V′) and volume( V) data were analyzed by nonlinear mode of respiratory motion. PEEPidyn was determined by esophageal balloon-tipped catheter technique. The correlations between PEEPidyn and Evd, Rvd as well as Evd ×Rvd were analyzed. Results The correlation coefficients between PEEPidyn and Evd, Rvd as well as Evd ×Rvd were 0. 85,0. 80, and 0. 90, respectively. Conclusions Nonlinear mode of respiratory motion is suitable to analyze respiratory mechanics of COPD patients mechanically ventilated using mode of PSV. There are good correlations between PEEPidyn and Evd,Rvd as well as Evd ×Rvd which may be used to noninvasively monitor PEEPidyn in mechanically ventilated COPD patients using mode of PSV.

    Release date:2016-08-30 11:54 Export PDF Favorites Scan
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