miR-185-5p alleviates the inflammatory response of acute gouty arthritis by inhibiting of IL-1β / 细胞与分子免疫学杂志

Objective To investigate the relationship between interleukin-1β (IL-1β) and miR-185-5p in the process of joint injury in acute gouty arthritis (AGA). Methods The serum miR-185-5p levels of 89 AGA patients and 91 healthy volunteers were detected by real-time quantitative PCR. The correlation between miR-185-5p expression level and VAS score or IL-1β expression level was evaluated by Pearson correlation coefficient method. Receiver operating characteristic (ROC) curve was used to evaluate the diagnostic value of miR-185-5p in AGA. THP-1 cells were induced by sodium urate (MSU) to construct an in vitro acute gouty inflammatory cell model. After the expression level of miR-185-5p in THP-1 cells was upregulated or downregulated by transfection of miR-185-5p mimics or inhibitors in vitro, inflammatory cytokines of THP-1 cells, such as IL-1β, IL-8 and tumor necrosis factor α (TNF-α), were detected by ELISA. The luciferase reporter gene assay was used to determine the interaction between miR-185-5p and the 3'-UTR of IL-1β. Results Compared with the healthy control group, the expression level of serum miR-185-5p in AGA patients was significantly reduced. The level of serum miR-185-5p was negatively correlated with VAS score and IL-1β expression level. The area under the curve (AUC) was 0.905, the sensitivity was 80.17% and the specificity was 83.52%. Down-regulation of miR-185-5p significantly promoted the expression of IL-1β, IL-8 and tumor necrosis factor (TNF-α), while overexpression of miR-185-5p showed the opposite results. Luciferase reporter gene assay showed that IL-1β was the target gene of miR-185-5p, and miR-185-5p negatively regulated the expression of IL-1β. Conclusion miR-185-5p alleviates the inflammatory response in AGA by inhibiting IL-1β.

Clinical value of complete lateral position endoscopic combined intra-renal surgery in treatment of staghorn kidney calculi / 中国医师进修杂志

Objective:To assess the safety and feasibility of complete lateral position endoscopic combined intra-renal surgery (ECIRS) in treatment of staghorn kidney calculi.Methods:The clinical data of 105 patients with staghorn kidney calculi from March 2016 to July 2022 in the First Hospital of Shanxi Medical University were retrospectively analyzed. Among them, 55 patients were treated with lateral position percutaneous nephrolithotomy (PCNL) (PCNL group), and 50 patients were treated with complete lateral position ECIRS (ECIRS group). The operative time, removal time of double J-tube, postoperative hospital stay, postoperative hemoglobin decrease value, operative complications (using Clavien-Dindo grading criteria), additional postoperative intervention and calculi free rate were compared between two groups.Results:Both groups of patients were successfully operated. The operative time, postoperative hemoglobin decrease value and rate of additional postoperative intervention in ECIRS group were significantly lower than those in PCNL group: (98.3 ± 19.1) min vs. (103.4 ± 16.5) min, (9.34 ± 3.04) g/L vs. (12.55 ± 4.75) g/L and 8.00% (4/50) vs. 21.82% (12/55), the calculi free rate was significantly higher than that in PCNL group: 90.00% (45/50) vs. 74.55% (41/55), and there were no statistical differences ( P<0.05 or <0.01); there were no statistical differences in the removal time of double J-tube, postoperative hospital stay, incidence of Clavien-Dindo≥ grade Ⅱ operative complications between two groups ( P>0.05). Conclusion:The complete lateral position ECIRS is a safe and effective treatment for staghorn kidney calculi, and is a good complement to the ECIRS technique because of its high stone free rate in phase Ⅰ, low complication incidence and easy dissemination.

Research progress of non-coding ribonucleic acid in pulmonaryartery hypertension / 中华胸心血管外科杂志

Non-coding RNA refers to a class of RNAs that cannot encode proteins, and they play a very important role in regulating cellular activities. Pulmonary arteryhypertension is a group of diseases characterized by progressive elevation of pulmonary vascular pressure. Its pathogenesis is complex and its influencing factors are numerous. The study found that non-coding RNA, as a transcription product that does not participate in translational functions, plays an important role in the pathogenesis of patients with pulmonary arteryhypertension. With regard to the more well-studied and relatively mature circRNAs, lncRNAs, and miRNAs in non-coding RNAs, this article review the pathophysiological processes involved in the formation of pulmonary arteryhypertension.

The value of synthetic MRI combined with diffusion weighted imaging in differential diagnosis of benign and malignant breast lesions / 中华放射学杂志

Objective:To evaluate the value of synthetic MRI combined with DWI in the diagnosis of benign and malignant breast lesions.Methods:The data of 184 consecutive patients with suspected breast lesions in Yunnan Cancer Hospital from July to September 2019 were prospectively analyzed. All patients were randomly assigned to training group ( n=110) and validation group ( n=74), and underwent conventional MRI and synthetic MRI respectively before and after contrast injection. At the maximum slice of the lesion, the ROI was drawn along the edge and recorded as "tumor". In the solid area with the most obvious tumor enhancement, the second ROI was drawn and recorded as "local". At the same time, ADC values (ADC local and ADC tumor) and relaxation time values (T local and T tumor) were measured. T and T + represented the relaxation time value of the ROI pre-and post-contrast scanning. ΔT% represented the relative change rate in T value between pre-and post-contrast scanning.The rank sum test was used to test the quantitative parameters of benign and malignant breast lesions in the training group and the validation group, and the variables with P<0.05 were included in the binary logistic regression analysis to screen the independent variables and establish the prediction model. The area under ROC curve was used to evaluate the discrimination of parameters and models. The clinical applicability of model was analyzed by decision curve analysis (DCA). Results:In the training group, univariate analysis showed that there were significant differences in T 1tumor, T 1+tumor, ΔT 1% tumor, T 2local, T 2+local, T 2tumor and T 2+tumor, ADC local, ADC tumor between benign and malignant breast lesions ( P<0.05). Multivariate logistic regression analysis showed that T 1+tumor, ΔT 1% tumor, T 2tumor, ADC local, ADC tumor were independent variables in the diagnosis of breast cancer. The relaxation time model (model A: T 1+tumor, ΔT 1% tumor, T 2tumor) and ADC model (model B: ADC local, ADC tumor) established by combining the above variables had the same diagnostic efficiency (AUC=0.905, 0.914, Z=-1.874, P=0.062), and the multi-parameter combination model (model C: T 1+tumor, ΔT 1% tumor, T 2tumor, ADC local, ADC tumor) had the highest diagnostic efficiency (AUC=0.965). DCA analysis showed that when the threshold probability ranges between 21%-99% (training cohort) and 15%-99% (validation cohort), the net benefit of model C was better than model A and B. Conclusion:The multi-parameter combined prediction model established based on the relaxation time value and ADC can identify breast cancer efficiently and can be used as an auxiliary diagnostic tool.

Application of percutaneous intervention in the treatment of benign biliary-enteric anastomosis stricture / 国际外科学杂志

Choledochojejunostomy is a common surgical method for the treatment of organ diseases such as hepatobiliary, gastrointestinal and pancreatic diseases, but there are many complications related to the operation. Benign biliary-enteric anastomosis stricture (BBES) is the most common long-term complication after operation, which seriously affects the quality of life of patients. At present, bile duct reconstruction and endoscopic treatment are the main methods to deal with BBES, but there are some limitations. The new interventional therapy has the advantages of small trauma, good repeatability, high success rate and few complications. It has been applied in many medical centers. The main treatment methods include percutaneous transhepatic biliary balloon dilatation, percutaneous temporary stent placement, percutaneous transhepatic choledochoscopy, magnetic compression anastomosis and intrabiliary ablation. Up to now, there is no uniform standard for the choice of interventional therapy for BBES at home and abroad, so it is of great clinical significance to establish a standardized interventional therapy strategy.

Low-dose chloroquine mediated neuroprotection against n-methyl-d-aspartate induced excitotoxicity in adult mice / 中华眼底病杂志

Objective:To investigate the protective effects of different concentrations of chloroquine on RGC in n-methyl-d-aspartate (NMDA) injured mice and its possible mechanisms.Methods:Fifty-four healthy male C57/BL6 mice were randomly divided into three groups, 18 in each group. The mice in low-dose chloroquine group were intraperitoneally injected with chloroquine solution at a dose of 10 mg/kg daily. Mice in high-dose chloroquine group were intraperitoneally injected with chloroquine solution at a dose of 100 mg/kg, and the mice in control group were intraperitoneally injected with the same volume of PBS. NMDA intravitreal injection was performed 2 days after intraperitoneal injection, 5 nmoles NMDA was injected into the left eye, and the same volume of PBS was injected into the right eye as a control. The RGC staining of retinal plaques were performed 7 days after NMDA injection, and the number of alive RGC was calculated. The visual acuity and electroretinogram were used to evaluate the electrophysiological functions of RGC at 9 and 10 days after modeling. Real-time quantitative PCR and retinal frozen sections and glial fibrillary acidic protein (GFAP) immunofluorescence staining were performed 11 days after NMDA injection to evaluate the glial activation of the retina. The density, visual acuity, and the amplitude of PhNR-wave of RGC between groups were compared by one-way analysis of variance.Results:At 7 days after NMDA injection, the density of RGC in retinal patch of low-dose chloroquine group was significantly higher than that of intraperitoneal injection of PBS control group ( F=54.41, P<0.01). The density of RGC in retinal patch of high-dose chloroquine group was lower than that of control group ( F=1.18, P>0.05). The visual acuity was higher than control group, and the difference was statistically significant ( F=9.10, P<0.05). The amplitude of PhNR-wave was significantly higher in low-dose chloroquine group than that of the control group ( F=17.60, P<0.01). The mRNA level of inflammatory factor and GFAP positive signal was also significantly lower than that of the control group ( F=23.66, P<0.05). The amplitude of PhNR-wave, the expression of GFAP ( F=110.20, P<0.01) and the mRNA level of inflammatory factors ( F=167.60, 17.78; P<0.01) in the high-dose chloroquine group were higher than the other two groups, and the differences were statistically significant. Conclusions:In NMDA injury retinal model, low-dose chloroquine significantly increased the survival and physiological function of RGC, and the mechanism may be related to the inhibition of glial activation and inflammatory response. High-dose of chloroquine would aggravate the apoptosis of RGC.

Comparison of biomechanical properties of cervical paravertebral foramen screws, lateral mass screws and pedicle screws / 中华骨科杂志

Objective:To investigate and compare the biomechanical strength of paravertebral foramen screws (PVFS), lateral mass screws (LMS) and pedicle screws (PS).Methods:A total of 30 human cervical spine vertebrae (C 3-C 6) were harvested from 8 fresh-frozen cadaver specimens whose mean age was 45.3±11.2 years at death. The vertebrae were randomly divided into three groups for specific screws. For each vertebra, one side was randomly chosen for direct pullout strength test (speed 5 mm/s), and the other side for fatigue test (displacement ±1.0 mm, frequency 1 Hz, 500 cycles) and residual pullout strength test. 4.5 mm × 12 mm screws were used for PVFS, 3.5 mm × 14 mm screws for LMS, and 3.5 mm × 24 mm screws for PS. Results:The direct pullout strength was 327.10±17.07 N for PVFS, 305.71 ± 11.63 N for LMS, and 635.67 ± 22.82 N for PS. The residual pullout strength was 265.62 ±18.19 N for PVFS, 192.80 ±17.10 N for LMS, and 494.89 ±41.79 N for PS. The residual pullout strength of PVFS, LMS and PS respectively, compared with the direct pullout strength, decreased by 18.8%, 36.93% and 22.15% ( tPVFS=7.795 , tLMS=17.267 , tPS=9.349 , P<0.001). The direct pullout strength of PS was higher than that of PVFS and LMS( t=34.245, t=40.741, P< 0.001), as well as PVFS was slightly higher than LMS ( t=3.275, P=0.004). The residual pullout strength of PS was the highest, PVFS was the second, and LMS was the smallest ( F=314.619, P<0.001). For the fatigue test, the load at the first cycle and the first time when the set position was reached of PVFS were higher than those of LMS ( t=3.625, P=0.002; t=5.388, P<0.001) and PS ( t=2.575, P=0.019; t=2.680, P=0.015), but there was no difference between those of LMS and PS ( t=0.609 , P=0.550; t=1.953 , P=0.067). The load at the last cycle of PVFS and PS was higher than that of LMS ( t=5.341 , P<0.001 ; t=3.439 , P=0.003), while there was no difference between PVFS and PS ( t=1.606, P=0.126). Conclusion:The direct pullout strength of PVFS was slightly higher than that of LMS, and the residual pullout strength was significantly higher than LMS. The property of fatigue resistance of PVFS was similar to PS and obviously better than LMS. In summary, PVFS can be used as an effective substitute for LMS and PS.

Application of single-cell RNA sequencing in visual system / 中华实验眼科杂志

Single-cell RNA sequencing (scRNA-seq) is an emerging technology that observes transcriptomes' differences between individual cells at the cellular level.The basic strategy is to capture single cells and lysis the cells to get mRNA, then amplify them after reversing transcriptions, finally cDNA is used to build sequencing libraries.At present, this technology has been widely used in many subject areas.Visual system includes retina, lateral geniculate nucleus, and visual cortex, etc.It's responsible for the acquisition and processing of visual information and the formation of vision.Visual information accounts for more than 70% of all sensory information.Therefore, the study of the visual system is particularly important.With the rapid development of science and technology, there are more and more research results on scRNA-seq.This technology is gradually becoming an important tool for guiding clinical practice, and has provided a bridge for basic research transforming to clinical research.In this review, we introduce the main technical routes and methods of scRNA-seq and detail its application in visual system.

Research progress of acute aortic syndrome / 中华外科杂志

Acute aortic syndrome(AAS) is a lethal disease with acute onset and a high mortality rate as well as a higher incidence rate especially in an aging population. The diagnostic techniques of AAS have been improving in recent years. Many serum biomarkers have been shown to have the potential of further clinical implication. Advancement of imaging techniques has also improved the accuracy of early diagnosis. Although traditional treatment modality involving open surgery is life-saving, it still has a high mortality rate and a high major morbidity rate. The increasing utilization of endovascular techniques has greatly improved the prognosis of AAS, while it still need further optimization to be applied in different subgroups of patients.

Fabrication and in vitro biological safety of a novel functional coating on microarc-oxidized titanium / 实用口腔医学杂志

Objective:To fabricate and to study the surface morphology and biological safety of a novel coating on microarc-oxidized titanium.Methods:The novel functional coating was fabricated by cross-linking the double-layer nanoparticles loading rhBMP-2 and SDF-1 with gelatin on microarc-oxidation coating on titanium implant surface.The surface topography was observed and optimized,and the biological safety of the novel coating was primarily evaluated by cell toxicity test,oral mucosa stimulation test and hemolysis test in vitro.Results:The novel functional coating possesses excellent morphology.The coating showed the cytotoxicity of score 1 and no mucous membrane irritation,the hemolytic rate of the coating was 4.6％.Conclusion:The coating possesses good morphology and biological safety.

Application of language intervention to alleviate the discomfort of patients during the colonoscopy process / 中国实用护理杂志

Objective To investigate the effect of the language intervention to reduce patients′discomfort during a colonoscopy examination. Methods A total of 72 subjects who accepted a colonoscopy process in the Digestive Endoscopy Department of the Dalian Central Hospital from September 2014 to December 2015 were divided by random number table method into two groups, 38 for the control group and 34 for the observation group. The control group adopted routine nursing care, while the observation group adopted the language intervention besides the routine nursing care, in accordance with the implementation steps of language intervention for patients who accepted the colonoscopy examination, which means the four stages , the four positions and the four methods. The first stage: the enteroscope entered the anus and arrived the rectum , applied the deep breathing with anal movement method . The second stage: from the rectum to the sigmoid colon, used the induce distraction method. The third stage: stimulated the patients′ excitement at the junctional area of descending colon and transverse colon (the spleen area). The fourth stage: at the junctional area of transverse and ascending colon (the liver ares), used the continuous excitation method. In each stage, individualized language intervention and psychological nursing were given to every patient in the observation group. The cooperating effect of the two groups were evaluated. Results The frequency of pain, the pain scores,the frequency of pressing and the average insertion time of the control group respectively were (8.68 ± 0.83) times,(45.08 ± 6.66) points, (5.73±0.75) times,(372.26±31.77) s, while the observation group were (4.53±0.38) times,(17.07± 3.01) times,(2.05±0.38) times,(268.61±14.51) s, less than the control group ,the t value respectively were 3.81,27.17,3.51,4.66, and the difference was significant (P<0.01 or 0.05). Conclusions Using the language intervention nursing method can significantly relieve the patients′ nervous and anxiety during the procedure, ease the pain and discomfort, shorten the insertion time, improve the subjects′ experience during the colonoscopy examination, make the patients more coordinate with the examination and complete it successfully.

Study on the fit of titanium alloy removable partial denture framework fabricated by selective laser melting / 实用口腔医学杂志

Objective:To evaluate the fit of titanium alloy removable partial denture framework fabricated by selective laser melting(SLM) technique.Methods:7 Kennedy Ⅲ Ti-6Al-4V removable titanium alloy partial denture frameworks were fabricated by SLM technology.An optical scanner was used to scan the gypsum model adhered with the silicone rubber film obtained by the impression method before and after removal of the film.Geomagic Qualify 2013 software was used to analyze the gap between the model and the tissue surface of the major connector of the framework,the fit of the frame work was evaluated.Results:The overall 3D deviation between the titanium alloy frameworks and the gypsum model was (0.221 9±0.07) mm.Conclusion:The fit of the titanium alloy removable partial denture framework made by SLM technology can basically met the clinical requirements.

A preliminary study on the forming quality of titanium alloy removable partial denture frameworks fabricated by selective laser melting / 中华口腔医学杂志

Objective@#To evaluate the processing accuracy, internal quality and suitability of the titanium alloy frameworks of removable partial denture (RPD) fabricated by selective laser melting (SLM) technique, and to provide reference for clinical application.@*Methods@#The plaster model of one clinical patient was used as the working model, and was scanned and reconstructed into a digital working model. A RPD framework was designed on it. Then, eight corresponding RPD frameworks were fabricated using SLM technique. Three-dimensional (3D) optical scanner was used to scan and obtain the 3D data of the frameworks and the data was compared with the original computer aided design (CAD) model to evaluate their processing precision. The traditional casting pure titanium frameworks was used as the control group, and the internal quality was analyzed by X-ray examination. Finally, the fitness of the frameworks was examined on the plaster model.@*Results@#The overall average deviation of the titanium alloy RPD framework fabricated by SLM technology was (0.089±0.076) mm, the root mean square error was 0.103 mm. No visible pores, cracks and other internal defects was detected in the frameworks. The framework fits on the plaster model completely, and its tissue surface fitted on the plaster model well. There was no obvious movement.@*Conclusions@#The titanium alloy RPD framework fabricated by SLM technology is of good quality.

Genetic analysis of a patient featuring developmental delay and mental retardation / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To explore the genetic cause for a child featuring developmental delay and mental retardation.</p><p><b>METHODS</b>The child was analyzed with G-banded karyotyping and an Illumina Human CytoSNP-12 Beadchip.</p><p><b>RESULTS</b>The father of the patient had a normal karyotype. The mother had a karyotype of 46, XX, t(12;15)(p13.3;q13). The child had a karyotype of 45, XY, der(12)t(12;15)(p13.3;q13)mat, -15. SNP array analysis showed that the child has deletions in 12p13.31-p13.33 and 15q11.2-q13.2. But no deletion or duplication was detected in his mother.</p><p><b>CONCLUSION</b>The unbalanced translocation involving chromosomes 12 and 15 probably accounts for the mental retardation in the child. SNP array is useful for the detection of chromosomal rearrangements and genetic counseling.</p>

Clinical diagnosis and surgical management of ureteral obstruction after renal transplantation / 中华器官移植杂志

Objective To investigate the diagnosis and surgical management of ureteral obstruction after renal transplantation.Method A respective study was performed on 15 cases of ureteral obstruction who received renal allografts.All of the cases were confirmed,including 5 cases of stenosis of ureterovesical junction,4 cases of stenosis of distal ureter,2 cases of blood clot blockage,2 cases of edema due to perforation of distal ureter,1 case of ureteral calculi,and 1 case of extrinsic compression of hematoma.All 14 patients underwent open surgical management to reestablish ureter with D-J catheter as stent for 12-16 weeks.One patient was subjected to percutaneous nephrostomy followed by percutaneous ureteroscopy,the obstructed site was identified at ureterovesical junction and antegrade balloon dilation and D-J stent in ureter were performed subsequently.Result Fifteen patients were diagnosed as ureteral obstruction by colour Doppler ultrasound and MRU.All of the patients were resolved the obstructions after surgical managements and the renal function got improved.No reobstruction occured during one year follow-up period.Conclusion Colour Doppler ultrasound and MRU can definitely be used to diagnose ureteral obstruction after renal transplantation.Early diagnosis and surgical management are very important.Open surgical management of the obstructed ureter is an effective method.Antigrade balloon dilation is a therapeutic approach to treat ureteral obstruction.

Association of single nucleotide polymorphism of interleukin 6 receptor gene and metabolic syndrome / 中华内分泌代谢杂志

The association of interleukin 6 receptor ( IL-6R ) gene - 183 A/G ( rs4845617 ) and Asp358 Ala (rs8192284 A/C) polymorphisms with metabolic syndrome was investigated in Chinese Han population.The result showed that the frequencies of AA genotype and A allele were higher in patients with metabolic syndrome ( MS ) than those in healthy subjects ( P＜0.05 or P＜0.01 ).The risk of MS in patients with A allele was 1.643 folds of that with allele C(95％ CI 1.163-2.320,P＜0.01 ).No differences were found in the genotype and allele frequencies of -183A/G between two groups ( P＞0.05 ).The Asp358Ala polymorphism of IL-6R was significantly associated with MS in Chinese Han population.

Shear mechanical properties of lumbar trabecular bone in aged people / 中国组织工程研究

BACKGROUND:Shear mechanical properties of lumbar trabecular bone should be understood in treating osteoporosis,bone remodeling,bone reconstruction,as well as the choice of fracture fixed equipment.OBJECTIVE:To explore whether the shear mechanical properties of lumbar trabecular bone is different in young and aged normal fresh cadavers.METHODS:Experimental samples were from 4 normal fresh corpse,aged 22,28,70 and 75 years,were provided by Department of Anatomy,Norman Bethune Medical University.Spinal column thoracic vertebra L_2-L_5 specimen were obtained from corpse within 1 hour and cut into 40 min×5 mm×5 mm pieces.The specimen were tested on electronic universal testing machine with speed of 5 mm/min,the shear load,stress,strain and other data would be printed automatically,and the morphology of fracture surface was observed.RESULTS AND CONCLUSION:Majority of the fracture surfaces were comminuted,minority were transverse or oblique fracture.The macroscopic observation showed that trabecular arranged compact in the thoracic vertebra cancellous bone of the youth group,which was sparse arrangement and presented with senile osteoporosis in the aged group.The shear force,shear stress and strain of the youth group was greater than that of the aged group[(37.19±3.25),(28.34±3.42) N;(1.49+0.13),(1.13±0.14) MPa;(1.40±0.50)%,(0.90±0.20)%,P＜0.05].It demonstrated that the impact mechanics properties of thoracic vertebra cancellous bone are different between the youth and aged groups.

Stress relaxation characteristics in brachial plexus of experimental animals using function as description method / 中国组织工程研究

BACKGROUND:The brachial plexus injury anastomosis suture technique is necessary to understand the mechanics characteristic of brachial plexus nerve stress relaxation.Previous studies mainly focused on single tension mechanics of brechial plexus nerve,but few studies concerning stress relaxation and creeping elasticity.OBJECTIVE:To observe and analyze experimental animal brachial plexus nerve stress relaxation mechanics characteristic in the description manner of function,to provide experimental parameters for clinic.DESIGN,TIME AND SETTING:The experimental observations to use function as a way to describe from 1~(st) to 10~(th_ March,2007 at the Experimental Center of Jilin University.MATERIALS:The experimental male Sprague Dawley rats aged 6 months were provided by Changchun Gaoxin Medicine Animal Experimentation Center.METHODS:The stress relaxation experiment was performed in Experimental animal Brachial plexus Nerve on the the electronic universal testing machine (Shimadzu,Japan).The stress relaxation experiment strain increased speed was 1%/s,setting time of 7 200 seconds.100 empirical data were collected and disposed by one-way linear regression analysis.MAIN OUTCOME MEASURES:The stress relaxation data and curve,the Stress and time change rule were measured.RESULTS:The stress relaxation quantity of animal brachial plexus nerve test specimen at 7 200 s was 0.316 MPa.Stress relaxation curve changed with logarithm.Stress relaxation changed rapidly at 600 seconds,decreased gradually,and reached a balance level at 7 200 seconds.CONCLUSION:The stress relaxation curve changed with the logarithm relations.Brachial plexus has visco-elastic mechanical properties.