0.05). Conclusions The LTs synthesis is elevated in RSV bronchiolitis and LTs may participate in the pathogenesis of RSV bronchiolitis. Leukotriene receptor antagonist may play an important role in RSV bronchiolitis. However there still needs further research on the relationship between LTs and eosinophils count in the pathogenesis of RSV bronchiolitis.

BACKGROUND: Three-dimensional (3D) printing technology is a new rapid prototyping and rapid manufacturing technology. OBJECTIVE: Through the analysis of the related papers, the paper summarizes and discusses the research progress of 3D printing technology, the prospect of application in joint replacement and the status quo and development trend of 3D printing technology in joint replacement.METHODS: The relevant literature was retrieved by the first author with the China Journal Full-text Database (CNKI) and PubMed database from 1985 to 2015. The key words were 3D printing technology, rapid prototyping, arthroplasty, joint replacement. The included 81 articles were analyzed.RESULTS AND CONCLUSION: Basic research and clinical application of 3D printing technology and joint replacementtechnology are becoming more and more popular. 3D printing further optimizes in the communication and teaching in joint replacement, and avoids intraoperative and postoperative complications. According to the needs of different teaching materials, 3D printing can print out different parts of the real body with different characteristics of print by 3D printer. The surgical simulation exercises with 3D limb printing different materials are the best way to improve theoperation skills. 3D printing technology in the osteotomy guide precision has basically completed multicenter clinical trial,and toward to the clinical application of small scale stage. The construction of individualized treatment plan and theapplication of active biological organs by 3D printing technology will become the new research direction of jointreplacement.

BACKGROUND:A new type of medical titanium alloy Ti2448 (Ti-24Nb-4Zr-7.9Sn) is by far the lowest initial modulus of titanium alloy, with the initial modulus of about 40 GPa, the average Young's modulus<20 GPa, and tensile strength of about 900 MPa;human tissue biocompatibility and mechanical compatibility are excellent. OBJECTIVE:To investigate the biomechanical properties of a new low elastic modulus spinal pedicle screw fixation system and compare it with Ti6Al4V pedicle screw. METHODS:Totally 60 fresh human cadaveric thoracic vertebrae were randomly selected:on one side, pedicle new low modulus Ti2448 pedicle screws, as the experimental group;on the other side, pedicle screw Ti6Al4V, as control group. The maximum bending load and maximum load displacement, maximum torque and maximum axial pul ing force of the two groups were detected. RESULTS AND CONCLUSION:There was no significant difference in the maximum bending load, maximum load displacement, maximum torque and maximum pulling force between the two groups. The results show that the maximum bending strength, the maximum torque and maximum pul out force in low elastic modulus of Ti2448 pedicle screw fixation system are consistent with the Ti6Al4V screws, which can meet the needs of internal fixation on spinal biomechanics strength.

Objective To study the causes of misdiagnosis for differentiated thyroid carcinoma in teenager, the re-operative indication and style as well as the prevention of complication. Methods The clinical data of 36 cases of re-operative treatment for differentiated thyroid carcinoma in teenager from 1991 to 2002 were analyzed retrospectively.Results The incidence of residual cancer and cervical lymphnode metastasis in the patients was 38.9% and 30.5% respectively. The re-operative complications included 2 cases of hoarseness, and 3 cases of hand and foot spasm. Five-year and ten-year survival rates after reoperation were 90.4% and 88.9%, respectively. Conclusion Thyroid nodules in teenager should be guarded against malignancy. FNAB(Fine-Needle Aspiration Biopsy) is helpful for diagnosis before the operation, and pathological observation of frozen section during operation must be performed as routine examination. Choosing suitabel operative style could raise the operative excision rate and quality of life. The improved operation skill could reduce the operative complications.

Objective To determine the effect of prone position (PP) ventilation on oxygenation in patients with acute respiratory distress syndrome (ARDS) .Methods Twenty-three patients of both sexes (14 males, 9 females) with ARDS (within 72 h after onset of ARDS) were included in this study. The patients ranged in age from 43-78 years. Ten minutes before the patients were placed in prone position, midazolam 2-5 mg was given i. v. followed by continuous infusion at 2-3 mg?h-1 for sedation and a bolus of vecuronium 4 mg per hour for muscle relaxation. The patients were mechanically ventilated (VT 6-8 ml?kg-1, inspiration-time 1.0-1.2 s, RR 12-20 bpm, FiO2 0.4-1.0, PEEP 6-18 cm H2O) . The patients were placed in prone position for 2 h. Radial artery was cannulated and S-G catheter placed. MAP, CVP, MPAP, PAWP, cardiac output, PaO2 , PaCO2 peak inspiratory pressure (PIP) and airway resistance (Raw) were measured and recorded immediately before (T0) and 0.5, 2 h after the patients were placed in prone position (T1 , T2) and 2 h after supine position was resumed(T3) . PaO2/FiO2 and static compliance of the respiratory system (Cst) were calculated. Results In 87% of the patients PaO2/FiO2 was significantly increased during prone position (T1, T2) as compared to the baseline (T0) (P

OBJECTIVE : To prepare the sustained release tablets of salbutamol sulfate,and to establish the method of quality control.METHODS: The sustained release tablets were prepared by using salbutamol sulfate, lactose, sodium carboxymethyl starch, HPMC, EC, and MCC and coated with enteric soluble acrylic resin.HPLC was employed to determine the content of salbutamol sulfate, while at the same time dissolution grade in vitro was determined, and stability was investigated.RESULTS: : The detectable concentration of salbutamol sulfate showed a good linear correlation with peak area in the range of 1.25～20.00?g/ml.The average recovery of salbutamol sulfate was 98.60% (RSD=0.66%).The prepared tablets showed a timing release 5 hours after administration.No evident changes in dissolution were found in all tests of stability.CONCLUSION: The formulation of the preparation is reasonable; the preparation technique is simple and feasible, and the quality is stable and controllable.

Objective To investigate the risk factors that affect the perioperative mortality incholangiocarcinoma.Methods The clinical data of sixty two patients with cholangiocarcinoma who underwent operation were reviewed retrospectively.Logistic regression test was used in the perioperative mortality study.Before multivariate analysis,each parameter was evaluated with univariate analysis to define whether it was of statistical significance(P

Augmenter of liver regeneration(ALR)is a novel hepatic stimulator. Owing to its peculiar characteristic of gene structure and many kinds of biological functions, it is thought to be an important hepatotrophic factor. This review summarized the advance in ALR research in recent years including characteristics of ALR gene, molecular structure, physiochemical characteristics, biological functions and roles in liver injury.

Objective To explore a safe,high efficiency and rapid approach for the repair of huge sacral pressure sores. Methods From 1993 to 2001,17 cases of huge sacral pressure sore were repaired using the pedicled upper part gluteus maximum myocutaneous flap .Results The outcome of repair in stage Ⅰ was satisfactory in all the cases during the followed-up period for 1～9 years,the size of the flap ranged from 16cm?10cm to 10cm?8cm,No recurrence was occurred,The function of gluteus in donor areas was keeped maximally. Conclusions The method is a good treatment for huge sacral pressure sores. It possesses the advantages of easiness to perform,rich blood supply,no necessity of free skin graft in the donor areas,less complications,high success rate. The treatment can be completed in one stage.It is worthy of popularization.

The co-metabolic carbon sources,dynamics and influence factors of atrazine biotransformation by genetically engineered microor- ganism(GEM)were investigated in the paper.The results showed that glucose was superior to acetate as co-metabolic carbon sources.The concentration of carbon sources affected little on atrazine transformation but much on GEM growth.The specific transformation rate(STR)of atrazine was influenced not by cell density of GEM but by atrazine concentration.Monod model was used to simulate atrazine transformation dynamics and the parameters were v_(max)=0.168/h and Ks=30.49 mg/L.When temperature reduced,STR decreased markedly.The trans- formation was efficient in weak alkaline condition and was inhibited in acidic condition.To some extent,salinity did not affect transformation activity of GEM.Co~(2+),Fe~(2+),Fe~(3+),and Zn~(2+) improved atrazine transformation,but Mn~(2+),Ni~(2+) and Cu~(2+) inhibited atrazine transforma- tion.The results also showed that there existed a direct correlation between adsorption and transformation of atrazine by GEM.