Objective To investigate the effects of the thickness of the adhesives(3 M ESPE RelyX ARC)on the internal stress distribution of the IPS Empress Ⅱ full-ceramic crowns by using Finite Element Analysis(FEA).Method A dummy Empress Ⅱ ceramic crown restoration of the mandible right first molar was prepared according to standard dental process.Followed by micro-CT scanning,four 3D numerical models with cement thickness 60,90,120 and 150 μm were established respectively.The models were subjected to four loading conditions and stresses in veneer and core layers were presented.Result Numerical results indicate that when adhesive thickness increases from 60 μm to 90 μm,the maximum principal stress either in veneer or core decreases.However,when thickness increases to 150 μm,stress variation trends differ from adhesives.Conclusions The normal stresses in adhesives remain a low level when the thickness varies from 90 μm to 120 μm,while the shear stress is less sensitive to the thickness when it exceeds 90 μm.There is an optimal thickness which can reduce the tensile stress in the core and veneer.Attention should be paid to the shear strength of the adhesives since the shear stress could cause failure in the adhesive layer.

Objective To construct three-dimensional finite element model of lumbar spondylolysis,then to verify its validity by comparison of biomechanics in vitro.Method According to the radiological data of a patient with lumbar spondylolysis,the bone and intervertebral disc of L4-S1 were reconstructed by Simpleware software.The lumbar attaching ligaments and articular capsule were added into simulating model by Ansys software.The three-dimensional finite element model of lumbar spondylolysis was finally simulated successfully,and validated by lumbar spondylolysis biomechanical experiment in vitro.Results The reconstruction of digital model contained the bones of lumbar spine which include vertebral cortical bone,cancellous bone,facet joint,pedicle,lamina,transverse process and spinous process,as well as the annulus fibrosus,nucleus pulposus,superior and inferior end-plates.Besides,anterior and posterior longitudinal ligaments,flavum ligament,supraspinal and interspinal ligaments and articular capsule of facet joint are also attached.The model consisted of 281,261 nodes and 661,150 elements.Imitation of spondylolysis is well done in this model.The validity of the model was verified by comparison of the results of biomechanics in vitro which involved in the trends under loading of stress/strain of L4 inferior facet process,L5 superior and inferior facet process,S1 superior facet process and the trends of stress/strain of lateral and medial L4 inferior facet process.Conclusions Three-dimensional model of lumbar spondylolysis is reconstructed using finite element analysis,and can be further used in the research in biomechanics of lumbar spondylolysis.

0.05). Conclusion It seems that LTA gene polymorphism has no significant correlation with the risk of osteoporosis in patients suffering from COPD.

Objective To translate and revise the Atrial Fibrillation-Quality of Life -18 (AF-QoL-18),and to test its reliability and validity. Methods The Chinese version of AF-QoL-18 was developed through the process of translation, back- translation, cultural adaptation, and preliminary experiment. A total of 187 atrial fibrillation (AF) patients in eight hospitals in Jiangsu province were investigated using the Chinese version to test the reliability and validity. Results Exploratory factor analysis identified three factors, including physiological, psychological and sexual dimensions, which could explain 65.055%of the total variance. The content validity index was 0.969. The Cronbach α coefficient was 0.915 and the retest reliability was 0.948 for the total scale. Conclusions The Chinese version AF-QoL-18 has proved to be reliable and valid.It can be used to measure the quality of life of AF patients in China.

Retinitis pigmentosa (RP) and age-related macular degeneration (AMD) are two predominant causes of visual deterioration. Retinal prosthesis embeds a micro-electric chip or a micro-photoelectric diode array in the sub-retina or epi-retina, which is used to stimulate the remainder of inner retina, so as to restore some degree of sight. Retinal prosthesis has attracted most attention in the field of artificial visual function recovery, and along with deep-going research, many issues need to be resolved. In this paper, the theory of retinal prosthesis and the status quo of research in many countries are introduced, the key issues which influence the application of the retinal prosthesis are discussed in detail, and some notions and advices are presented.
Electric Stimulation Therapy ; instrumentation ; methods ; Humans ; Macular Degeneration ; surgery ; Photic Stimulation ; instrumentation ; methods ; Prosthesis Design ; Retinitis Pigmentosa ; surgery ; Visual Prosthesis ; standards ; trends

Objective To explore the functional improvement of dancers' sensorimotor system after years of dance training.Methods Twenty-three dancers(the dance group) of more than 6 years of dancing experience and twenty-one college students (the control group) without any dance experience were recruited in this study.Then the resting state functional magnetic resonance imaging(RS-fMRI) was conducted for both groups and the data were collected.Regional homogeneity (ReHo),fractional amplitude of low frequency fluctuation (fALFF) and functional connectivity (FC) were compared between the two groups.Results Compared to the control group,significant increase was observed in the ReHo of the bilateral postcentral gyruses,the left superior temporal gyrus,the right precentral gyrus and the middle occipital gyrus and fALFF in the bilateral precentral gyruses of the dance group.Moreover,the connection between the right precentral gyrus and left precentral gyrus and the FC between the right precentral gyrus and bilateral postcentral gyrus enhanced significantly in the dance group compared to the control group.Conclusions The functional modulation of dancers' sensorimotor system may be associated with the long-term dancing experience,which may lead to the changes in action perception,memory processing,motor learning and movement control to enhance the formation of the mode to observe,implement and adjust complex actions.Our study has provided a supporting evidence for dancing-induced brain plasticity.

The mosquito vector of filariasis malayi and its vectorial capacity was investigated In 5 endemic villages in Leshan Prefecture, Sichuan Province. The results showed that the man-biting rate, numan blood index and vectorial capacity of An. lesteri anthropophagus were 0.7, 5.1 and 10.63 times higher than those of An. sinensis. Besides, the natural infection by microfilaria in An, lesteri anthropophagus was also higher than that in An. sinensis by 5 times.From the above result, the authors concluded that An. lesteri anthropophagus was the main vector for transmitting filariasis malayi in the area under study.

Objective To analyse the value of serum alpha fetoprotein(AFP),keratin antigen 21-1(CY-FRA21-1)and neuron specific enolase(NSE)in the diagnosis and prognosis of lung cancer.Methods A total of 89 patients with primary lung cancer were selected as the primary lung cancer group from June 2014 to June 2016.The other 59 cases of benign lung disease were selected as the benign lung disease group,and 63 cases of healthy physical examination were collected as normal group.The content of AFP,CYFRA21-1 and NSE were detected by electrochemiluminescence assay.Results Before treatment,the levels of AFP,CYFRA21-1 and NSE in the benign lung disease group and the primary lung cancer group were significantly higher than those in the normal group,those in the primary lung cancer group were significantly higher than those in the benign lung disease group(P<0.05).The levels of AFP,CYFRA21-1 and NSE in patients with stage Ⅲ aand Ⅲ b-Ⅳ were significantly higher than those in patients with stage Ⅰ - Ⅱ,and those in Ⅲ b- Ⅳ stage were signifi-cantly higher than those in Ⅲ astage(P<0.05).The sensitivity,specificity,accuracy of two joint tests were significantly higher than those of the single test,those of the three joint tests were significantly higher than those of the single test and the two combined tests,and the differences were statistically significant(P<0.05).The AFP,CYFRA21-1 and NSE of the patients in the ineffective group were significantly higher than those in the effective group,and the differences were statistically significant(P<0.05).Conclusion Tumor markers AFP,YFRA21-1 and NSE are of great value in the diagnosis and treatment of lung cancer,joint detec-tion could improve the positive rate and accuracy of diagnosis.

Objective To investigate the diagnostic value ofbiomarkers in cerebrospinal fluid in differentiating meningeal carcinomatosis (MC) and tubercular meningitis (TBM).Methods The clinical features and cerebrospinal fluid (CSF) test results of 34 patients with MC and 44 patients with TBM,admitted to our hospital from January 1994 to August 2014,were retrospectively analyzed and compared.Results The main clinical manifestations of MC included headache and bowel and bladder dysfunction,and those of TBM were fever and headache.The cell population of MC and TBM patients increased and the number of leucocyte of TBM patients was significantly larger than that of MC patients (P＜0.05);the CSF of all the patients presented with decreased levels of glucose and chloride,and increased protein level,and higher protein in MC patients was noted than that in TBM patients (P＜0.05).The biomarkers in CSF of MC and TBM patients increased to varying degrees,and the biomarkers,including carcinoembryonic antigen (CEA),cancer antigen (CA) 125,CA 199,CA 153 and CYFRA21-1,in MC group were significantly higher than those in TBM group (P＜0.05).The neuron-specific enolase level in the TBM patients of Ⅲ grade was significantly higher than that in the MC patients (P＜ 0.05).Conclusion The detections of tumor biomarkers in cerebrospinal fluid is a tool in differentiating MC and all stages of TBM,especially with the combined detections of CEA,CA125,CA199 and CYFRA21-1.

Objective:To review our clinical experience on total pancreatectomy in treatment of pancreatic diseases.Methods:The clinical data of 25 patients with pancreatic diseases who underwent total pancreatectomy at Nanjing Drum Tower Hospital from February 2016 to October 2019 were retrospectively analyzed. The data on general information, surgical methods, postoperative complications, changes in postoperative pancreatic endocrine and exocrine functions and quality of life were analyzed.Results:There were 16 males and 9 females, aged (60.9±9.4) years. Planned selective surgery was carried out in 16 patients while unplanned operations in 9 patients. There were 15 patients with pancreatic neoplasms with 4 patients who received neoadjuvant or conversion therapy, 6 patients with intraductal papillary mucinous neoplasms, 3 patients with chronic pancreatitis and 1 patient with pancreatic neuroendocrine carcinoma. The total postoperative complication rate was 36% (9/25). One patient died in the perioperative period, and one patient underwent a second operation. After 6 months of operation, 2 of 24 patients had died. The remaining patients had a fasting blood sugar of (8.9±1.6) mmol/L, with an insulin dosage of (30.7±10.6) U/d. The average dosage of trypsin was (1.1±0.3) g/d. The quality of life score reached or exceeded the preoperative levels.Conclusions:Total pancreatectomy was safe and feasible for some pancreatic diseases. For patients with pancreatic cancer, its long-term oncological outcomes need further studies.