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A structure scheme for a novel 6-DOF hybrid machine tool（ HMT） is proposed. In this scheme,a novel 4-PRP redundantly actuated parallel mechanism is proposed as the position module,which can realize three motion,with assistance of the 3-UPS&PU parallel mechanism,6-DOF machining can be realized. Firstly,the three-dimensional translations and three-dimensional rotations motion of this machine tool are analyzed based on screw theory. Then,the inverse displacement analysis model is provided by using analytical methods and the geometric relation of the mechanism. And the first-order influence coefficient matrix-Jacobian matrix and the second order influence coefficient matrix-Hessian matrix and complete kinematics model are established by using the influence coefficient method. At last,the position inverse solution is obtained by using MATLAB and the results simulation verification is carried out by using ADAMS,which verify that the correctness of the inverse displacement analysis model and the realizability of the mechanism.

The Lagrange method is applied to build dynamics model of the 6 DOF redundantly actuated hybrid machine tool. Firstly,the configuration of the 4-PRP + 3-UPS&PU machine tool is analyzed,and the coordinate system is established. Then,the expression of kinetic energy and potential energy of the machine tool are educed,and the equivalent generalized force of non-conservative force is analyzed,and the dynamics model is established by using the Lagrange method,which laid the foundation for the solution of driving force and dynamics analysis. Finally,combining with numerical examples,the numerical results of the dynamics model of the 4-PRP + 3-UPS&PU redundant drive hybrid mechanism and mechanism driving rod drive curve are obtained by MATLAB,and the correctness and feasibility of the dynamic model is verified by ADAMS simulation results.

A novel large swing angle 1T2R parallel mechanism is proposed. First,the one-dimensional translational and two-dimensional rotation motion of this mechanism are analyzed based on the relation of motion and constraint in screw theory. The DOF of the mechanism is calculated,and the driving joints are chosen.Then,the inverse position solution equation of the mechanism is established by using analytical vector method and the geometric relation. At last,the position inverse solution is obtained by using MATLAB and the results simulation verification is carried out by using ADAMS,which verify that the correctness of the inverse position solution model and the realizability of the mechanism. This parallel mechanism with a large swing angle,can be used in hybrid machine of parallel modules to achieve large swing angle five-axis machining.

Objective To find a rational way in early detecting the residual Tumor in patients with nasopharyngeal carcinoma ( NPC) after radiotherapy. Methods A total of 47 NPC patients who were diagnosed residual tumor after radiotherapy and treated in our hospital from Dee 2009 to Aug 2012 were included in this study and their clinicopathological and follow-up data were reviewed and analyzed. The patients were checked by nasopharynx MRI, FDG PET-CT and were examined by biopsy of the residual tumors within two weeks after radiotherapy. The diagnosis of relapses was determined by pathological re-examination. Results AH the 47 patients were followed up for 10-42 months. Three of them had nasopharynx relapse. The others had not tumor relapse and their residual tumors disappeared completely. The specificity of MRI, FDG PET-CT and pathological tumor response in diagnosing residual tumors were 9.1%, 77.3%, and 95. 5% (P <0. 001). Their accuracy rates were 14.9%, 78.9%, and 95. 7% , respectively (P <0. 001 ). The M of SUV max in the team who had moderate and severe pathologic tumor response (team A) was 3. 05 and that in the team who had mild pathologic tumor response (team B) was 4. 68 (P =0. 012). None of patients in the team A had nasopharynx relapse. Three patients in the team B who had SUV max ⩾4 had nasopharynx relapses, and in other 2 patients who had SUV max <4, the residual tumors disappeared during the following-up. The specificity and accuracy in diagnosing residual tumors were increased when mild pathologic tumor response combined with SUV max4 were used. Conclusion PET-CT combined with pathologic tumor response is beneficial for early diagnosis of residual nasopharyngeal tumors alter radiotherapy. [ABSTRACT FROM AUTHOR]

Astrocytes are the most abundant cells in the central nervous system and play significant roles in normal brain. With cerebral infarction, astrocytes are activated as reactive astrocytes and form glial scars, which play an essential part in brain injury. According to their roles in neuroprotection after cerebral infarction, regulation of scar formation, nerve regeneration, maintenance of blood-brain barrier, promotion of angiogenesis and immune response, scholars have proposed a variety of therapeutic strategies based on targeting astrocytes. This article reviews the research progress on the changes in astrocyte signaling pathways before and after cerebral infarction and the related therapeutic strategies.

Objective: To identify a HEK293 cell line containing stably-transfected H3R gene, and to screen the novel non-imidazole compounds with H3R antagonist activity., Methods: The expression of rat H3 receptor in cell line was detected by RT-PCR and Western blot. An elevation of intercellular cAMP concentration induced by forskolin was measured as the index for screening compounds with H3R antagonist activity., Results: The H3R-transfected HEK-293 cells stably expressed high level of rat H3 receptor mRNA and protein. Forskolin significantly increased intercellular cAMP concentration in the H3R-transfected HEK-293 cells. H3R agonist (R)-α-methylhistamine inhibited the forskolin-induced production of intercellular cAMP. H3R antagonist thioperamide and newly synthesized non-imidazole compounds XHA23 and XHA25 blocked (R)-α- methylhistamine reversal of forskolin-induced cAMP formation in a concentration-dependent manner, and the IC50 values were 3.62 μmol/L, 0.49 μmol/L, 0.14 μmol/L, respectively., Conclusion: The H3R-transfected HEK293 cells stably express high level of rat H3 receptor, and can be used for screening compounds with H3R antagonist activity. The non-imidazole compounds XHA23 and XHA25 may have H3R antagonist activity.