BACKGROUND:A selection of treatment for thoracolumbar fracture is very important.OBJECTIVE:To develop and validate three-dimensional finite element models of human thoracolumbar fracture using varying fixation methods,and to compare biomechanical characteristics of fixation method.DESIGN TIME AND SETTING:A contrast observation was performed at the Mechanical Experiment Center of Tongji University from August to October 2008.MATERIALS:64-slice spiral CT (Siemens,Germany) was used to scan T_(11)-L_1 segments of an adult male,and the slice thickness was 0.6 mm.based on Boolean operation,the lower half of T_(12) segment was resected,and the structure of posterior part was reserved to establish finite element model of thoracolumbar fracture.METHODS:There were five groups in this study,including 4 pedicle screws+2 rods (group 1),5 pedicle screws+2 rods at one side (group 2),6 pedicle screws+2 rods at both sides (group 3),anterior fixation (group 4),and anterior plus posterior fixation (group 5).Forces of axial compressive,anterior bending,posterior extension,left bending,and right rotation were loaded to compare the biochemical characteristics.MAIN OUTCOM MEASURES:vonMises stress and displacement at different directions.RESULTS:The stresses of all the fixation screws increased from the anterior part to posterior part in all movement tests,and the strongest stress was measured in the joint position.The stress of proximal screw was stronger than that of the distal screw.Additionally,the stress in group 1 was significantly stronger than in groups 2,3,and 5 (P<0.01).The group 5 was the most stable,but the group 1 was the poorest.CONCLUSION:T_(12) bursting fracture models were established using varying fixation methods,and the results verified that short segment plus fracture vertebral segmental fixation has more superior biomechanics.

Objective To evaluate the physical functions of community-dwelling older adults, and analyze the related factors. Methods From September to October, 2016, 80 adults over 55-year-old in one community in Wuhan, Hubei, China were selected with convenience sampling. General situation was collected through questionnaires. Physical functions were measured by tests of grip strength, Five-Times-Sit-to-Stand Test (FTSST), modified Clinical Test of Sensory Interaction and Balance (mCTSIB) and TimedUp and GoTest (TUGT). Their correlation was analyzed. Results The average grip strength of the participants was (27.46 ± 9.66) kg; the average time of FTSST was (11.58 ± 4.03) s;there was only one (1.25%) participant observed with an impairment in mCTSIB;the average time of TUGT was (9.05±3.47) s. Grip strength was correlated with gender (r=-0.669), education level (r=0.238), the score of Mini-Mental State Examina-tion (MMSE) (r=-0.302) and activities of daily living (ADL) (r=-0.344) (P<0.05). The time of FTSST was correlated to gender (r=0.274), the score of MMSE (r=0.243) and ADL (r=0.321) (P<0.05). The time of TUGT was correlated to gender (r=0.255), education level (r=-0.362), income level (r=-0.245), the score of Self-rating Depression Scale (r=0.223), the score of MMSE (r=0.328) and ADL (r=0.354) (P<0.05). Conclusion The levels of grip strength, FTSST and TUGT are related to the demographic characters in community-dwell-ing older adults. Little abnormity has been found in mCTSIB.

Since the reform of the supply side has been put forward by General Secretary Xi Jinping,the research and practice of the health industry has been strengthened for the reform of the supply side,and the beneficial exploration has been carried out on the supply side structure reform.The various forms of medical alliance are the feasible way to solve the problem of supply side.Through such a reform,it can make full use of medical resources to meet the needs of the people's medical treatment.The construction of medical alliance practice in Beijing Chaoyang Hospital is analyzed,and on this basis,proposals of the medical alliance construction are put forward.

With the development of the prenatal medicine, the survival rate of the premature has im-proved obviously. However,doctors should focus on the ethics problem whether treat the extreme survival and critical diseased premature is necessary. During the process,the attitude of parents and the medical care personnel impact the premature survival rate. Therefore, the role excellent communication skills and the hospital ethics committee to improve the premature rate and avoid the medical conflict should not be ignored.

Objective To compare the value of MRI and CT in the diagnosis of rectal cancer staging.Methods This study performed a retrospective survey and analyzed the data of 98 cases of preoperative imaging,including MRI and CT images,and the results were compared with the postoperative pathological examination,to evaluate the value of preoperative diagnosis of the two methods.Results The diagnostic accuracy of MRI in T1,T2,T3 (92.1％,74.4％,80.0％) were higher than those of CT (79.4％,29.2％),the diagnostic accuracy of MRI in N0,N1,N2 on (77.6％,83.3％) were higher than those of CT(49.0％,46.2％,30.0％),the difference was statistically significant (x2 =9.55,P ＜ 0.05).In the lymph node metastasis,MRI misdiagnosis rate (20.0％,3/15) was slightly lower than that of CT (26.7％,4/15).Conclusion For patients with rectal cancer,MRI in the diagnosis of T1-T3,N staging were is better than CT,it is an ideal preoperative diagnosis method,it is and is worthy of clinical application for reference.

[Objective] Aneurysmal bone cyst of the ealeaneus is an uncommon entity. The purpose of the report is to describe aneurysmal bone cyst of the ealcaneus seen in a child.[ Methods] The clinical, radiological and histopathologic findings of a boy with aneurysmal bone cyst of the calcaneus were retrospectively analyzed with reference to literature. [ Results ]The tumor mainly involved the right calcaneus. He was treated successfully after the curettage and bone grafting. Histopathological examination revealed an aneurysmal bone cyst of the right calcaneus. He is now disease-free for 2 years, and no sign of recurrence was found. [ Conclusion] Aneurysmal bone cyst of the calcaneus is an uncommon entiy. To simple aneurysmal bone cyst,curettage and bone grafting are effective therapic method.

AIM: To establish quality standard for prepared pieces of Rhizoma Panacis Majoris. METHODS: Traditional identification and TLC were used for qualitative analysis of prepared pieces. The contents of ginsenoside Ro and chikusetsusaponin IVa were determined by HPLC. Water,ash and acid-insoluble ash were also detected. RESULTS: The average content of ginsenoside Ro was 7. 19% ,chikusetsusaponin IVa was 3. 16% from different habitants. CONCLUSION: The established method has been proved to be simple,stable,accurate,and can be applied to the determination of ginsenoside Ro and chikusetsusaponin IVa in Rhizoma Panacis Majoris. The quality control standards for Rhizoma Panacis Majoris is normative and the result is accurate.

Given the significant improvement in terms of its coverage and compensation depth,China's basic medical insurance system has inherent setbacks in its structure as held by the authors.They hold that the medical insurance as the most important source of compensation for medical institutions,should further reform its structure of financing and reasonably raise the percentage of compensation; adjust the time reference and space reference for prepayment estimation such as the total prepaid amount; deepen supportive reforms for the payment manner.All these measures aim at minimizing impact of the payment control mechanism on routine medical activities and exploring diversified payment manners that are feasible.

Objective To study the effect of positive pressure ventilation extubation on arterial blood gas indexes of patients undergoing cardiac surgery. Methods 50 patients with orotracheal intubation after intracardiac opening operation under direct vision were randomly divided into the control group and the experimental group with 25 cases in each group. We used traditional method to pull out tracheal intubation in the control group. And positive pressure ventilation at 5 ～15 cm H2O during inspiration and pulling out tracheal intubation during expiration in the experimental group. The change of arterial blood PaO2, PaCO2, SaO2, pH and respiratory rate before and 1min、5min、10min after extubation was observed,and also the incidence rate of air tube obstruction was recorded. Results The change amplitude of arterial blood gas indexes of patients in the experimental group was obviously lower,and the length of change time reduced more than 50%. There were 4 air tube obstructions in the control group and there was no obstruction in the experimental group. The difference was statistically significant. Conclusions Positive pressure ventilation extubation can raise lung's compliance and improve oxygenation. And arterial blood gas indexes are more stable. It can decrease the incidence rate of hypoxemia and is a much more safe method.

Objective To observe the expression of oxidized purine nueleoside triphosphatase MTH2 in the hippocampi of senescence-accelerated mouse P8(SAMP8). Methods Randomly selected SAMP8 and its control strain SAMRl aged 1-,4-,8-and 12-month and performed immunohistochemisry and Western blot analysis to explore the expression changes of MTH2 in the 2 groups of mice. Results The MTH2 protein was detected in cytoplasm and nuclei of neurons throughout the whole hippocampus of SAMRl at all ages.There were no obvious changes of SAMR1 in both CA1 and CA3 subregions,but an age-related decline of MTH2 protein in both regions of SAMP8 was found.The optieal density(OD)value of Cal hippoeampus(0.0473),CA3 hippoeampus (0.0510)were significantly less in 8-month old mice than in the 4-month old[CA1:0.0619,CA3:0.06803(all P＜0.05).By immunoblot analysis,the grey values of MTH2 expression were 0.529,0.313,0.032 in hippoeampus of 4-12 months-old SAMP8 mice,and significantly Iower than in the age-matched SAMR1 mice(all P＜0.05). Conclusions MTH2 deficiency may be a new factor involved in the accelerated aging and in deficits of learning and memory ability in SAMP8.