By using three-dimensional finite element analysis method, the necessity of tail joints in the establishment of finite model specifically for the widely used tail-suspended rat experiments in weightlessness simulation was explored. A weightlessness tail-suspended three-dimensional finite element rat model was established using CT scan and Abaqus software, and the computation and analysis were conducted using the same model. The stress distribution and displacement in tail, lumbar spine, pelvis and femur of a tail-suspended rat both with and without cartilage were simulated and calculated.The results showed that stress distribution and displacement of tail-suspended rat were quite different between rats with cartilage and without cartilage, which affected the calculation precision of the model. Accordingly the consideration of articular cartilage in establishing the tail-suspended three-dimension finite element rat model is quite necessary,In addition, the asymmetry of pelvis stress distribution of tail-suspended rat suggests that the degree of balance of tail-suspended rat will affect the stress distribution in rats.

Objective To assess the role of CA 125 monoclonal antibody in the differential diagnosis of primary ovarian carcinoma and metastatic ovarian carcinoma originated from the gastrointestinal tract Methods Immunohistochemical study using CA 125 monoclonal antibody was performed on 33 primary ovarian cancer and 50 metastatic ovarian cancer of gastrointestinal origin Results The positivity of CA 125 was 84 5% in 33 cases of primary ovarian carcinoma, while in 50 metastatic ovarian carcinoma cases, only 4 0% was CA 125 positive The positivity of CA 125 was significantly higher in primary ovarian carcinoma than metastatic ovarian carcinoma ( P

Objective To study the imaging value in diagnosis of congenital cholangiectasis.Methods The clinical and imaging (CT and ultrasonics) data of 6 patients with congenital cholangiectasis were restrospectively analyzed with literature review.Results According to Todani's classifications of cholangiectasis,there were type I in one case,CT showed cystic hypodense shadow with thin and smooth wall;type IV in 4 cases,CT showed cystic or fusiform extension of intra-and extra-hepatic bile ducts;type V in one case,CT showed cystic extension of intra-hepatic bile ducts,and the central spot enhancement could be seen on contrast-enhanced CT scan.6 cases underwent ultrasonic examinations,ultrasound showed extension of intra-and extra-hepatic bile ducts in 6 cases,choledochal cyst in one.4 cases suspected with congenital cholangiectasis,and misdiagnosed in one.In company with cholecystitis and cholelithiasis in one,biliary carcinoma in one and cirrhosis in one.Conclusion CT and US are of important value in diagnosis of congenital cholangiectasis.

Objective To provide theoretical basis for clinical treatment of all-ceramic crown prosthodontics,the influence of cement thickness on the stress distribution in all-ceramic crowns under load was studied numerically.Methods The finite element analysis(FEA) model of a standard mandibular first molar was established using spiral CT and CAD software,and then it was applied to analyze the stress distribution of all-ceramic crowns under vertical loading using FEA software.Results Stress concentration was found in mesial and distal cement;the stress distribution at the cement upper and lower interface was found to be similar,and the stress magnitude discrepancy between the two interfaces was small;the stress of the model with 0.15 mm cement in the cervix was lower about 30% than the one of the 0.05 mm model.Conclusions The cement thickness plays an important role in the stress distribution of all-ceramic restoration system.The model with 0.15 mm cement shows a better resistance to destruction among the three models investigated.

Objective To study the stability of micro-implant orthodontic anchorage(MA)with different pitch in the case of immediate loading.Method Employing 3D finite element analysis method,the stress and dis-placement distribution on the bone interface of MIA with different pitch(0.3 mm、0.5 mm、0.7 mm and 1.0 mm,respectively),which was 1.47 N loaded vertically in the major axis direction,were analyzed.Result The pitch affected the stress distribution significantly,because the maximum stress increased with the pitch decreasing and the impact of pitch on stress distribution on neck and central locations of MIA were different;to decrease the pitch could reduce the max displacement of the jaw,but the impact of pitch on displacement distribution of MIA was not significant.Condusions In the case of immediate loading.MIA with pitch 0.5 mm-0.7 mm is suggested to be selected as orthodontic anchorage in the clinic.

Osteonecrosis is the most common disorder in femoral head and scaphoid. However, avascular necrosis (AVN) in metacarpal head is a rare disease. In the present study, a 14-year-old male patient complained of right-hand pain with a limited range of motion for one month. Physical examination showed that the active flexion was 70° and the extension was limited to 30° of the metacarpophalangeal (MCP) joints. The grip strength decreased to 60% of the contralateral hand. X-rays demonstrated flattening and sclerotic changes in the long finger and ring finger of metacarpal head. CT scanning indicated cystic, osteochondral defects and sclerotic changes in metacarpal head. Imaging examination further confirmed the diagnosis of AVN in the long metacarpal finger and ring finger. After conservative treatments including splint immobilization, non-steroidal anti-inflammatory drugs (NSAIDs) and physiotherapy, the local pain symptoms of the MCP joint gradually disappeared. The range of motion of MCP joint returned to normal with the grip strength score as 105% of the contralateral hand. MRI confirmed excellent remodeling and regeneration in the metacarpal head at two years later. The clinical characteristics, diagnosis and treatments of AVN of metacarpal head were reviewed. Although radiograph examination is commonly used, early-stage osteonecrosis of the metacarpal head should be confirmed by MRI. Given the rarity of this disorder, there is no consensus on the treatments. Metacarpal necrosis is the more common disorder in adolescent patients with a history of trauma. Considering the potential of bone remodeling, juveniles with metacarpal head necrosis could recover by conservative treatments.

In this study, a 3D model of a transtibial monolimb and residual limb was constructed. The stresses on all nodes of the model under the simulus of the load at the Mid-Stance were computed through 3D finite element analysis (FEA). The stress distribution on the internal and external surfaces of the model was obtained. The results indicate that the stresses on socket are lower than those on prosthetic shank; high stress regions are located on the underneath of prosthetic shank and the border section of socket and prosthetic shank. These data will be useful for CAD\CAM system of monolimb designing.
Artificial Limbs ; Finite Element Analysis ; Stress, Mechanical

A three-dimensional finite element model of the maxillary canine was developed including periodontal ligament, pulp and alveolar bone. And the stress distributions in the periodontal tissue were obtained under different orthodontic force. The specific aims were to make the model by means of the more advanced and accurate twin CT, to provide more accurate data for clinical use, and to build a more accurate model for the simulation of maxillary canine movement under orthodontic forces.
Cuspid ; Dental Stress Analysis ; Finite Element Analysis ; Humans ; Maxilla ; Models, Biological ; Orthodontic Appliances ; Periodontal Ligament ; physiopathology ; Periodontium ; physiopathology ; Stress, Mechanical ; Tooth Movement Techniques

Objective To study the expression of BCL10 and associated chromosomal aberration in primary cutaneous marginal zone B-cell lymphoma (PCMZL). Methods Tissue specimens were collected from 17 patients with PCMZL. Immunohistochemistry was used to detect the expression of BCL10. Fluorescence in situ hybridization (FISH) was performed to examine the presence of API2-MALT1 fusion gene and chromosomal aberration in BCL10, MALT1 as well as IgH genes in these cases. Results Of these patients,94.1% (16/17) expressed BCL10 protein. The cytoplasmic expression of BCL10 was observed in 64.7% (11/17) of the patients, and nuclear expression in 29.4% (5/17). As shown by FISH test, neither API2-MALT1 fusion gene nor chromosomal aberration in BCL10, MALT1 or IgH genes was present in these patients. Conclusions Compared with MALT lymphomas originating from tissues other than skin, PCMZL is uncommonly associated with chromosomal abnormalities; it is possible that there are unknown factors contributing to its tumorigenesis. Nuclear BCL10 is unrelated to the presence of chromosomal aberration in BCL10, MALT1 or IgH genes. Further follow-up is required to clarify the association between nucle ar BCL10 and poor prognosis of PCMZL.

Objective To explore the effect of Angiopoietin-2(ANG-2) and Endostatin (ENS) in patho genesis and development of endometriosis. Methods Twenty-five endometriosis cases and 24 controls were enrolled. ANG-2 and ENS in endometrium were detected by Immunohistochemistry. The concentrations of ANG-2 and ENS in peri-toneal fluid were measured with enzyme linked immunoabsorbant assay. Results In the EMs group, ANG-2 positive rate in eutopic endometrium was significantly higher than that of ectopic endometrium. The ANG-2 positive rate in ectopic endometrium was significantly higher than that of control group; in EMs group, the ENS positive rate in ec-topic endometrium was significantly higher than that in eutopic endometrium. The ENS positive rate in eutopic endo-metrium was significantly higher than that in control group. There was no significant difference of ANG-2 or ENS between stage Ⅰ～Ⅱand stage Ⅲ～Ⅳ. In peritoneal fluid, ANG-2 and ENS concentration and ratio of ANG-2/ ENS in endometriosis were significantly higher than that in controls. Conclusion The effect of angiopoietin-2 and endostatin in angiogenesis of endometriosis are important play a role in pathogenesis and development of the endo-metriosis.