Finite element is a common means to study pelvic biomechanics. This article introduces current methods to establish finite element model and application advances of the models in pelvis,and explores issues and future developing direction of pelvic finite element models.

Mr. Wang Hui respects but is not stubborn to ancient,paying attention to combination of differentiation of signs and diseases; in smartly applying Canker-root Wendan Decoction,he often adds Chendanxing to reinforce removing heat and sputum,emphasizing that signs of red tongue,yellow and greasy or white moss,bitter mouth,slippery and quick pulse show sputum heat bothering internal,can apply the formula,which embodying the treatment principle of "treat different diseases with same method".

Objective To evaluate the clinical efficacy of combination of Beyond cold light whitening and fluoride removing material bleaching sys-tem for treatment of dental fluorosis. Methods Ninety patients with light,medium and heavy dental fluorosis were recruited for the study and ran-domly divided into three groups. Thirty patients with 180 dental fluorosis from the A group were treated with microbrasion and etch and Beyond cold light bleaching. Thirty patients with 175 dental fluorosis from the B group were treated with microbrasion and beyond cold light bleaching. Thirty pa-tients with 180 dental fluorosis from the C group were treated with etch and Beyond cold light bleaching. The effects of whitening were evaluated by Vita shade guide matching after treatment. Results Good lightening efficacy and 100%bleaching efficacy was achieved in the light dental fluorosis subjects from all the three groups. The Shade value improvement and overall efficacy of observer group were better than the control groups for the me-dium and heavy fluorosis(P<0.05). Conclusion For moderate to severe dental fluorosis,combination of orderly methods ofmicro-polished-etch-Beyond cold light-bleachingis more effective and convenient.

Objective:Through 51 SPECT and SPECT/CT systems for performance test results of the collation and analysis, to understand the status of the operation of the SPECT and SPECT/CT systems, and in-depth analysis of indicators and find out the weak links and puts forward suggestions for improvement. Methods:According to the NEMA standards and requirements of the manufacturer, the systems have been tested on intrinsic uniformity, intrinsic spatial linearity, intrinsic spatial resolution, maximum count rate, system sensitivity, system spatial resolution and tomographic spatial resolution. Results:The results show that the majority of SPECT or SPECT/CT systems can pass the test;the failure rate is 9.80%. And the failures mainly show intrinsic uniformity and intrinsic spatial linearity. Conclusion:It is effective to improve the equipment performance by doing well in the daily quality control, regular maintenance and calibration, reducing factors that influence the inherent uniformity and inherent linear.

OBJECTIVE To lower the incidence of postoperative pulmonary infection in abdominal major operation.METHODS We performed a retrospective trial analysis on pulmonary infection after major abdominal operation in 402 cases from Oct 2004 to Oct 2005,and in the meanwhile effective preventive procedures were conducted.RESULTS Thirty three cases with pulmonary infection went weel with active treatment and nursing.CONCLUSIONS The predisposing factors for postoperative infection include anesthetic method,incision pain,and environmental pollution.The better methods for prevention of pulmonory infection are good preoperative instruction,planned respiration training,keeping airway confluent postoperatively,effectively reducing incision pain,infection control,and preventing environmental and air pollution.

This article makes a summary on the vascular access issues related to pediatric blood purification and progress,especially in view of the characteristics,principles of selection,maintenance and development direction of various vascular access in application of children patients.

Objective To analyze the influence factors on, and the relationship between, the system performance parameters by testing SPECT equipment.Methods By reference to National Electrical Manufactures Association standards and manufacturer's specifications, the performances of a total of 31 SPECTs in 12 provinces were measured, for the first time, with regard to their system spatial resolution (SSR) , system planar sensitivity (SPS) and tomographic spatial resolution (TPR).Results The results were as follows: (7.90 ± 0.62) mm for SSR, with the highest 9.46 mm and the lowest 7.04 mm;(78.54± 13.17)s-1· MBq-1 for SPS, with the highest 123.80 s-1 · MBq-1 and the lowest 56.70 s-1·MBq-1;and (13.12 ± 2.59) mm for TSR, with the highest 18.13 mm and the lowest 8.45 mm.These values indicated a nearly consistent upward and downward trend and could meet the clinical requirements by comparison with the manufactuer' s specifications.Conclusions Mutual restrictions have been shown between SSR and SPS.Increased thickness of the system crystal plane can improve the SPS, but also has a negative impact on the SSR.For all the above reasons, it is the optimum solution to choose the right type of collimator and crystal thickness for different clinical applications.

Forensic Ballistics ; Humans ; Maxillofacial Injuries ; surgery ; Wounds, Gunshot ; surgery

Disuse-related osteopenia is mainly due to decrease of bone formation which relates closely to the changes of osteoblast function and differentiation. Bone marrow mesenchymal stem cells which are multipotent cells present in bone marrow can differentiate into osteoblast. The factors which regulate the osteogenic differentiation of bone marrow mesenchymal stem cells were introduced. This will increase the understanding and aid in the prevention and treatments of bone loss to create a healthier life for astronauts and patients after disuse.

Objective:It is to discuss results and significance of PET/CT in the performance tests.Methods: According to NEMA NU 2-2007 Performance Measurements of Positron Emission Tomographs and GB 17589-2011 specifications for quality assurance test for computed tomography X-ray scanners standards, with phantoms of nuclear medicine and CT, performance testing was done.Results: Spatial Resolution (FWHM): transverse 1 cm 4.16 mm, axial: 1 cm 4.04 mm, transverse 10 cm 4.92 mm, axial: 10 cm 5.74 mm. Sensitivity: 9.6 s-1·kBq-1, scatter fraction: 35.4%, peak NEC rate: 1.69×105 s-1.Conclusion: According to manufacturers and national standards, the results of performances testing are up to standard. It is necessary to enhance the effect of in quality control(QC) of PET/CT and the fundamentality of the performance tests, so that the devices come to the demands for clinical practice.