1.A meta-analysis of risk factors for residual back pain after vertebral augmentation for osteoporotic vertebral compression fractures
Peng YANG ; Chenghan XU ; Yingjie ZHOU ; Xubin CHAI ; Hanjie ZHUO ; Lin LI ; Jinyu SHI
Chinese Journal of Tissue Engineering Research 2026;30(3):731-739
OBJECTIVE:Patients with osteoporotic vertebral compression fractures still have residual back pain after vertebral augmentation.The current research is characterized by limited sample size,complex confounding factors,and inconsistent research results.To gain a deeper understanding of this phenomenon,the aim of this study was to identify and evaluate the risk factors for residual back pain after surgery through a systematic review and meta-analysis.METHODS:A comprehensive search was conducted in CNKI,VIP,WanFang,CBMdisc,PubMed,The Cochrane Library,Embase,and Web of Science for case-control studies on residual back pain after vertebral body augmentation for osteoporotic vertebral compression fractures from database inception to July 2024.The search terms were a combination of subject terms and free terms.The basic information,patient characteristics,surgical-related indicators,and risk factors for surgical back pain of the included studies were extracted.After evaluating the bias risk of all included studies,a meta-analysis was conducted using Stata 14.0 software on the relevant indicators.RESULTS:(1)21 case-control studies with a total of 8 043 patients were included.Among them,965 patients developed back pain.The quality score of all 21 studies was ≥7.(2)The meta-analysis results showed that age(WMD=0.98,95%CI:0.40-1.56,P=0.010),bone mineral density(WMD=-0.28,95%CI:-0.34 to-0.21,P=0.000),the number of vertebral fractures(OR=3.50,95%CI:2.65-4.62,P=0.000),thoracolumbar fracture index(OR=3.65,95%CI:2.61-5.11,P=0.000),cement volume(OR=6.89,95%CI:2.62-18.17,P=0.000),and cement distribution(OR=2.38,95%CI:1.93-2.93,P=0.000)were risk factors for the development of back pain after vertebral body augmentation in patients with osteoporotic vertebral compression fractures.CONCLUSION:Current evidence indicates that age,bone mineral density,the number of vertebral fractures,thoracolumbar fracture index,bone cement injection volume,and the distribution of bone cement are risk factors for low back pain.Specifically,bone mineral density,the number of vertebral fractures,thoracolumbar fracture index,and non-uniform distribution of bone cement are identified as independent risk factors for low back pain.Patients exhibiting these high-risk factors require vigilant monitoring and prompt intervention to mitigate the occurrence of clinical low back pain,thereby enhancing patient outcomes and quality of life.
2.A meta-analysis of risk factors for residual back pain after vertebral augmentation for osteoporotic vertebral compression fractures
Peng YANG ; Chenghan XU ; Yingjie ZHOU ; Xubin CHAI ; Hanjie ZHUO ; Lin LI ; Jinyu SHI
Chinese Journal of Tissue Engineering Research 2026;30(3):731-739
OBJECTIVE:Patients with osteoporotic vertebral compression fractures still have residual back pain after vertebral augmentation.The current research is characterized by limited sample size,complex confounding factors,and inconsistent research results.To gain a deeper understanding of this phenomenon,the aim of this study was to identify and evaluate the risk factors for residual back pain after surgery through a systematic review and meta-analysis.METHODS:A comprehensive search was conducted in CNKI,VIP,WanFang,CBMdisc,PubMed,The Cochrane Library,Embase,and Web of Science for case-control studies on residual back pain after vertebral body augmentation for osteoporotic vertebral compression fractures from database inception to July 2024.The search terms were a combination of subject terms and free terms.The basic information,patient characteristics,surgical-related indicators,and risk factors for surgical back pain of the included studies were extracted.After evaluating the bias risk of all included studies,a meta-analysis was conducted using Stata 14.0 software on the relevant indicators.RESULTS:(1)21 case-control studies with a total of 8 043 patients were included.Among them,965 patients developed back pain.The quality score of all 21 studies was ≥7.(2)The meta-analysis results showed that age(WMD=0.98,95%CI:0.40-1.56,P=0.010),bone mineral density(WMD=-0.28,95%CI:-0.34 to-0.21,P=0.000),the number of vertebral fractures(OR=3.50,95%CI:2.65-4.62,P=0.000),thoracolumbar fracture index(OR=3.65,95%CI:2.61-5.11,P=0.000),cement volume(OR=6.89,95%CI:2.62-18.17,P=0.000),and cement distribution(OR=2.38,95%CI:1.93-2.93,P=0.000)were risk factors for the development of back pain after vertebral body augmentation in patients with osteoporotic vertebral compression fractures.CONCLUSION:Current evidence indicates that age,bone mineral density,the number of vertebral fractures,thoracolumbar fracture index,bone cement injection volume,and the distribution of bone cement are risk factors for low back pain.Specifically,bone mineral density,the number of vertebral fractures,thoracolumbar fracture index,and non-uniform distribution of bone cement are identified as independent risk factors for low back pain.Patients exhibiting these high-risk factors require vigilant monitoring and prompt intervention to mitigate the occurrence of clinical low back pain,thereby enhancing patient outcomes and quality of life.
3.Study on the correlation between serum Hcy,HGB,and HCT levels and the severity of condition and inflammatory factor levels in patients with chronic atrophic gastritis
Mei XUE ; Wei JIA ; Xubin LI ; Chunbo KANG ; Haiying SUN
International Journal of Laboratory Medicine 2025;46(3):319-324
Objective To investigate the correlation between serum homocysteine(Hcy),hemoglobin(HGB)and hematocrit(HCT)levels and the severity of condition and inflammatory factor levels in patients with chronic atrophic gastritis.Methods A total of 122 patients with chronic atrophic gastritis admitted to a hospital from January 2022 to December 2023 were selected as the disease group,and the disease group was di-vided into mild group(n=63)and severe group(n=59)according to pathological grades,and 106 healthy volunteers who underwent physical examination in a hospital during the same period were selected as the con-trol group.Clinical data of patients were collected and binary Logistic regression analysis was performed to an-alyze the factors affecting the severity of patients'condition,and Pearson correlation analysis was used to ana-lyze the correlation between Hcy,HGB,HCT and the levels of inflammatory factors.Receiver operating char-acteristic(ROC)curve was drawn to analyze the diagnostic value of Hcy,HGB and HCT on the severity of patients'condition.Results Compared with the control group,the serum Hcy level in the diseased group was increased,the serum HGB and HCT levels were decreased,the difference was statistically significant(P<0.05).Compared with the mild group,the serum Hcy level in the severe group was increased,the HGB and HCT levels were decreased,and the difference was statistically significant(P<0.05).Compared with mild group,the levels of C-reactive protein(CRP),tumor necrosis factor-α(TNF-α)and interleukin(IL)-6 in se-vere group were increased,and the levels of IL-10 were decreased,with statistical significance(P<0.05).Bi-nary Logistic regression analysis showed that Hcy and CRP were the risk factors affecting the severity of pa-tients'condition(P<0.05),and HCT,HGB and IL-10 were the protective factors affecting the severity of pa-tients'condition(P<0.05).Hcy was positively correlated with CRP,TNF-α and IL-6,and negatively correla-ted with IL-10(P<0.05).HGB and HCT were negatively correlated with CRP,TNF-α and IL-6,and posi-tively correlated with IL-10(P<0.05).ROC curve analysis showed that the area under the curve of serum Hcy,HGB,HCT and the combined diagnosis of the severity of patients'condition were 0.834,0.814,0.822 and 0.923,respectively,and the combined diagnosis value of the three was significantly better than that of Hcy(Z=2.519,P=0.012),HGB(Z=2.660,P=0.008)and HCT(Z=2.596,P=0.009)alone.Conclusion The increase of serum Hcy and the decrease of serum HGB and HCT in patients with chronic atrophic gastritis are correlated with the severity of the patient's condition and the level of inflammatory factors.The combined de-tection of the three can be used for the diagnosis of the severity of chronic atrophic gastritis.
4.A machine learning-based model for predicting the risk of diabetic kidney disease in type 2 diabetes mellitus
Tingting LI ; Peng SU ; Jinbo CHEN ; Xiaoyan HE ; Yi CAO ; Xin ZHANG ; Qingling TANG ; Xubin MIAO ; Xiaohua LIANG ; Dong MA
Chinese Journal of Diabetes 2025;33(4):241-247
Objective To compare and find an optimal model for predicting the risk of DKD occurrence in patients with type 2 diabetes mellitus(T2DM).Methods A total of 2005 patients with T2DM were enrolled in this study from The Second Hospital of Shijiazhuang City during December 2017 to December 2022.All the subjects were divided into a training set(n=1403)and a validation set(n=602)according to the ratio of 3∶1 by simple random sampling.With the occurrence of DKD as the outcome variablein the training set,important feature variables were screened by LASSO regression.Six different machine learning models were established according to the feature variables,thenthe optimal model was determined by comparison,and anonlinerisk predictor for DKD occurrence was constructed in patients with T2DM.Results Taking the occurrence of DKD as the outcome variable in the training set,the results of LASSO regression analysis showed that the optimal value of the model was 10-fold cross validation lambda.1se=0.01662473,and 15 characteristic variables with nonzero coefficient were screened out to be related to the occurrence of DKD.The data included sex,age,family history of DM,DM duration,LDL-C,HbA1c,WBC,PDW,Scr,urine α1-microglobulin,urine β2-microglobulin,urine microalbumin,hypertension,hypokalemia,and DR.In the training set and validation set,the prediction performance of XGBoost model was better than that of other models(AUC=0.872,0.893,95%CI 0.853~0.891,0.865~0.921),the sensitivity was 0.779,0.863,and the specificity was 0.721,0.758,respectively.The F1 scores were 0.774 and 0.787.DCA analysis showed that the XGBoost model had a greater net benefit and threshold probability.According to the XGBoost model,the online predictor of DKD risk in T2DM patients was laid out,and two patients were selected for application,the results showed that the predictive value of the model was 0.185 in non-DKD patients,and the predictive value was 0.510 in DKD patients.Conclusions The XGBoost model is the best model for predicting the occurrence of DKD in T2DM patients,and an online predictor was successfully built.
5.A machine learning-based model for predicting the risk of diabetic kidney disease in type 2 diabetes mellitus
Tingting LI ; Peng SU ; Jinbo CHEN ; Xiaoyan HE ; Yi CAO ; Xin ZHANG ; Qingling TANG ; Xubin MIAO ; Xiaohua LIANG ; Dong MA
Chinese Journal of Diabetes 2025;33(4):241-247
Objective To compare and find an optimal model for predicting the risk of DKD occurrence in patients with type 2 diabetes mellitus(T2DM).Methods A total of 2005 patients with T2DM were enrolled in this study from The Second Hospital of Shijiazhuang City during December 2017 to December 2022.All the subjects were divided into a training set(n=1403)and a validation set(n=602)according to the ratio of 3∶1 by simple random sampling.With the occurrence of DKD as the outcome variablein the training set,important feature variables were screened by LASSO regression.Six different machine learning models were established according to the feature variables,thenthe optimal model was determined by comparison,and anonlinerisk predictor for DKD occurrence was constructed in patients with T2DM.Results Taking the occurrence of DKD as the outcome variable in the training set,the results of LASSO regression analysis showed that the optimal value of the model was 10-fold cross validation lambda.1se=0.01662473,and 15 characteristic variables with nonzero coefficient were screened out to be related to the occurrence of DKD.The data included sex,age,family history of DM,DM duration,LDL-C,HbA1c,WBC,PDW,Scr,urine α1-microglobulin,urine β2-microglobulin,urine microalbumin,hypertension,hypokalemia,and DR.In the training set and validation set,the prediction performance of XGBoost model was better than that of other models(AUC=0.872,0.893,95%CI 0.853~0.891,0.865~0.921),the sensitivity was 0.779,0.863,and the specificity was 0.721,0.758,respectively.The F1 scores were 0.774 and 0.787.DCA analysis showed that the XGBoost model had a greater net benefit and threshold probability.According to the XGBoost model,the online predictor of DKD risk in T2DM patients was laid out,and two patients were selected for application,the results showed that the predictive value of the model was 0.185 in non-DKD patients,and the predictive value was 0.510 in DKD patients.Conclusions The XGBoost model is the best model for predicting the occurrence of DKD in T2DM patients,and an online predictor was successfully built.
6.A comparative study of short-term clinical outcomes of total laparoscopic and laparoscopic- assisted radical resection of distal gastric cancer: a propensity score-matched analysis
Shenxiang LONG ; Xinning WANG ; Xubin WANG ; Xuehui MAO ; Shubo TIAN ; Leping LI ; Xiaobo GUO
Chinese Journal of General Surgery 2024;39(2):86-91
Objective:To analyze the short-term clinical outcomes of total laparoscopic distal gastrectomy (TLDG) and laparoscopic-assisted distal gastrectomy (LADG) combined with Billroth-Ⅱ+Braun anastomosis.Methods:Clinical characteristics of patients undergoing laparoscopic distal gastrectomy combined with Billroth-Ⅱ+Braun anastomosis at Department of Gastrointestinal Surgery, Shandong Provincial Hospital Affiliated to Shandong First Medical University from Jan 2020 to Oct 2022 were analyzed. Patients were divided into TLDG group ( n=62) and LADG group ( n=62) according to the surgical approach. Results:There were significant differences in the preoperative clinical data section between the two groups, and 124 patients (62 in each group) were enrolled after using propensity score matching to balance significant variables. Compared with the LADG group, the TLDG group showed statistically differences in time to first venting [(2.9±1.3) vs. (2.3±0.8) d, Z=-3.072, P=0.002], time to first fluid diet [(5.9±1.3) vs. (5.4±1.4) d, Z=-2.031, P=0.042] and incision length [(7.1±1.4) vs. (4.8±0.8) cm, Z=-6.331, P=0.000]. Total postoperative complication rate in the TLDG group and the LADG group (29% vs. 37%, χ2=0.911, P=0.340) was not statistically significant. Incidence of postoperative pneumonia was lower in the TLDG group than in the LADG group (3% vs. 13%, χ2=3.916, P=0.048), and incidence of all remaining postoperative complications were not statistically significant. There was no statistically significant difference in the incidence of serious postoperative complications between the TLDG and LADG groups ( P=1.000). Multifactorial analysis revealed that male ( P=0.023) and age ≥65 years ( P=0.001) were independent risk factors for postoperative complications. Conclusion:TLDG is safe and feasible and has better short-term clinical efficacy than LADG.
7.Meta-analysis of the incidence and related factors for cervical spine instability in patients with rheumatoid arthritis
Chenghan XU ; Hanjie ZHUO ; Xubin CHAI ; Yong HUANG ; Bowen ZHANG ; Qin CHEN ; Yupeng HAO ; Lin LI ; Yingjie ZHOU
Chinese Journal of Tissue Engineering Research 2024;28(24):3922-3929
OBJECTIVE:At present,there are many reports on the related factors associated with the incidence of cervical spine instability in patients with rheumatoid arthritis,but there are problems such as small sample size and many confounding factors,and the research results of various studies on the same related factors are also different.This article analyzed the factors related to cervical spine instability in patients with rheumatoid arthritis by means of a systematic review. METHODS:Articles related to cervical spine instability in patients with rheumatoid arthritis were collected by searching both Chinese and English databases until March 2023.The outcome of cervical spine instability in patients with rheumatoid arthritis was used as the grouping criterion to abstract basic information,baseline patient characteristics,laboratory-related tests,medication use,and other relevant risk factors.Meta-analysis was done using Stata 14.0 software. RESULTS:(1)Sixteen relevant studies,all of moderate or above quality,were included,including seven studies with case-control studies and nine with cross-sectional studies.The overall incidence of cervical spine instability in patients with rheumatoid arthritis was 43.08%.(2)Meta-analysis showed:Related risk factors included female(OR=0.60,95%CI:0.44-0.82,P=0.002);age at disease onset(SMD=-0.52,95%CI:-0.86 to-0.18,P=0.003);duration of disease(SMD=0.58,95%CI:0.14-1.02,P=0.01);body mass index(OR=0.74,95%CI:0.63-0.88,P=0.001);rheumatoid factors positive univariate analysis subgroup(OR=1.33,95%CI:1.02 to 1.72,P=0.04),C-reactive protein(SMD=0.26,95%CI:0.16-0.35,P=0.00),erythrocyte sedimentation rate(SMD=0.15,95%CI:0.002-0.29,P=0.047),anti-cyclic-citrullinated peptide antibodies(OR=1.73,95%CI:1.19-2.51,P=0.004),28-joint Disease Activity Score(SMD=0.20,95%CI:0.04-0.37,P=0.02),destruction of peripheral joints(OR=2.48,95%CI:1.60-3.85,P=0.00),and corticosteroids(OR=1.91,95%CI:1.54-2.37,P=0.00)were strongly associated with the development of rheumatoid arthritis-cervical spine instability.Female and corticosteroid use were independently associated with the occurrence of rheumatoid arthritis-cervical spine instability. CONCLUSION:Based on clinical evidence from 16 observational studies,the overall incidence of rheumatoid arthritis-cervical spine instability was 43.08%.However,the incidence of cervical spine instability in rheumatoid arthritis patients varied greatly among different studies.Gender(female)and the use of corticosteroids were confirmed as independent correlation factors for the onset of cervical spine instability in patients with rheumatoid arthritis.The results of this study still provide some guidance for early clinical recognition,diagnosis,and prevention of rheumatoid arthritis-cervical spine instability.
8.Predictive value of serum Fbg and PTX3 levels for perioperative major adverse cardiovascular events in elderly patients undergoing hip replacement surgery
Huaiqian LI ; Tongtao PANG ; Jun LI ; Lei FAN ; Xubin ZHANG
International Journal of Laboratory Medicine 2024;45(21):2638-2641,2646
Objective To explore the predictive value of serum fibrinogen(Fbg)and pentaxin-3(PTX3)levels for perioperative major adverse cardiovascular events(MACE)in elderly patients undergoing hip re-placement surgery.Methods A total of 201 patients who underwent hip replacement surgery in the Qilu Hos-pital of Shandong University,Dezhou Hospital(the hospital)from January 2022 to December 2022 were re-garded as the study group,and based on the presence or absence of MACE during the perioperative period,pa-tients were separated into the non MACE group(183 cases)and the MACE group(18 cases).Another 150 healthy examinees from the hospital were selected as the control group.Fully automated biochemical analyzer and enzyme linked immunosorbent assay(ELISA)were applied to detect serum Fbg and PTX3 levels in re-search objects.Multivariate Logistic regression was applied to analyze the influencing factors of perioperative MACE in elderly patients undergoing hip replacement surgery.Receiver operating characteristic(ROC)curve was applied to evaluate the predictive value of serum indicators for perioperative MACE in elderly patients un-dergoing hip replacement surgery.Results Compared with the control group,the serum Fbg and PTX3 levels in the study group were obviously increased,and the differences were statistically significant(P<0.05).There were 18 cases who had MACE in elderly patients undergoing hip replacement surgery,with an incidence rate of 8.95%.Compared with the non MACE group,the serum Fbg and PTX3 levels in the MACE group were obviously increased,and the differences were statistically significant(P<0.05).Elevated serum Fbg,PTX3,cardiac troponin I(cTnI),brain natriuretic peptide(BNP)levels,and decreased left ventricular ejection fraction were independent risk factors for perioperative MACE in elderly patients undergoing hip arthroplasty(P<0.05).The area under the curve(AUC)of single and combined detection of serum Fbg and PTX3 levels for predicting the occurrence of perioperative MACE in elderly patients undergoing hip arthroplasty was 0.824,0.809,and 0.917,respectively.The combined prediction value of the two was higher than that of indi-vidual prediction(Z combination-Fbg=2.333,P=0.019;Z combination-PTX3=3.110,P=0.001).Conclusion The periop-erative serum Fbg and PTX3 levels in elderly patients undergoing hip replacement surgery are elevated,and the combination of the two has good predictive value for the occurrence of perioperative MACE.
9.Posterior vertebral column resection combined with polymethylmethacrylate-augmented pedicle screw instrumentation and shortening of spinal column for stage Ⅲ Kümmell's disease with very severe collapse of fractured vertebra
Xubin JI ; Feng LI ; Zhaowan XU ; Naiwang CHEN ; Dayong LIU ; Yang ZHANG ; Qinmin WU ; Wanping ZHU ; Xiaopeng LI ; Long LI
Chinese Journal of Orthopaedic Trauma 2023;25(7):601-609
Objective:To investigate the feasibility and clinical efficacy of posterior vertebral column resection (PVCR) combined with polymethylmethacrylate-augmented pedicle screw instrumentation and shortening of spinal column for stage Ⅲ Kümmell's disease with very severe collapse of fractured vertebra.Methods:From January 2017 to September 2021, 9 patients with stage Ⅲ Kümmell's disease with very severe collapse of fractured vertebra underwent PVCR combined with polymethylmethacrylate-augmented pedicle screw instrumentation and shortening of spinal column. Their medical records were retrospectively analyzed. There were 1 male and 8 females, aged (66.9±5.8) years. The injured vertebra was located at T 11 in 2 patients, at T 12 in 4, at L 1 in 2 and at L 2 in 1. X-ray, CT and MRI were performed before operation. The posterior intervertebral heights of adjacent vertebral bodies of the fractured vertebra in the median sagittal position were measured on CT or MRI to evaluate the shortening of the spinal column before PVCR. Recorded were intraoperative bleeding volume, operation time, complications, bone graft fusion, and American Spinal Injury Association (ASIA) grading at preoperation and the last follow-up. The visual analogue scale (VAS) pain scores, Oswestry disability index (ODI) scores, and kyphotic cobb angles at preoperation, 1 week and 3 months postoperation, and the last follow-up were compared to evaluate the clinical efficacy of PVCR. Results:All patients underwent surgery successfully, with tight closure of adjacent vertebrae after resection of the injured vertebra and bone grafting. Operation time was (240.6±23.2) min and intraoperative bleeding (505.6±95.0) mL. The 9 patients were followed up for (17.3±5.6) months. No worsening symptoms of nerve injury, cerebrospinal fluid leakage, or other serious complications were found after operation, nor such complications as loosening or breakage of internal fixation or adjacent vertebral fractures. Bone fusion was achieved at the bone graft sites in all patients by the last follow-up. The VAS and ODI scores and cobb angles at 1 week and 3 months postoperation and at the last follow-up were significantly decreased compared with preoperation ( P<0.05). There were no significant differences in VAS scores or cobb angles among postoperative 1 week and 3 months and the last follow-up ( P>0.05), but pairwise comparisons between different time points after operation showed significant differences in ODI, with postoperative 1 week > postoperative 3 months > the last follow-up ( P<0.05). The ASIA grading at the last follow-up was improved from preoperative grade C to grade D in 2 cases, from preoperative grade C to grade E in 1 case and from preoperative grade D to grade E in 5 cases. Conclusion:PVCR combined with polymethylmethacrylate-augmented pedicle screw instrumentation and shortening of spinal column is a feasible and effective surgical treatment for stage Ⅲ Kümmell's disease with very severe collapse of fractured vertebra, leading to good clinical efficacy.
10.Graded-Three-Dimensional Cell-Encapsulating Hydrogel as a Potential Biologic Scaffold for Disc Tissue Engineering
Zhixiang LI ; Yiwen ZHANG ; Yupeng ZHAO ; Xubin GAO ; Zhonglian ZHU ; Yingji MAO ; Taibao QIAN
Tissue Engineering and Regenerative Medicine 2022;19(5):1001-1012
BACKGROUND:
Intervertebral disk (IVD) degeneration, which can cause lower back pain, is a major predisposing factor for disability and can be managed through multiple approaches. However, there is no satisfactory strategy currently available to reconstruct and recover the natural properties of IVDs after degeneration. As tissue engineering develops, scaffolds with embedded cell cultures have proved critical for the successful regeneration of IVDs.
METHODS:
In this study, an integrated scaffold for IVD replacement was developed. Through scanning electron microscopy and other mechanical measurements, we characterized the physical properties of different hydrogels. In addition, we simulated the physiological structure of natural IVDs. Nucleus pulposus (NP) cells and annulus fibrosusderived stem cells (AFSCs) were seeded in gelatin methacrylate (GelMA) hydrogel at different concentrations to evaluate cell viability and matrix expression.
RESULTS:
It was found that different concentrations of GelMA hydrogel can provide a suitable environment for cell survival. However, hydrogels with different mechanical properties influence cell adhesion and extracellular matrix component type I collagen, type II collagen, and aggrecan expression.
CONCLUSION
This tissue-engineered IVD implant had a similar structure and function as the native IVD, with the inner area mimicking the NP tissue and the outer area mimicking the stratified annulus fibrosus tissue. The new integrated scaffold demonstrated a good simulation of disc structure. The preparation of efficient and regeneration-promoting tissueengineered scaffolds is an important issue that needs to be explored in the future. It is hoped that this work will provide new ideas and methods for the further construction of functional tissue replacement discs.

Result Analysis
Print
Save
E-mail