RESUMEN

In a craniotomy, the milling cutter is one of the most important cutting tools. The operating performance, tool durability and cutting damage to patients are influenced by the tool's sharpness, intensity and structure, whereas the cutting characteristics rely on interactions between the tool and the skull. In this study, an orthogonal cutting experiment during a craniotomy of fresh pig skulls was performed to investigate chip formation on the side cutting and face cutting of the skull using a high-speed camera. The cutting forces with different combinations of cutting parameters, such as the rake angle, clearance angle, depth of cut and cutting speed, were measured. The skull bone microstructure and cutting damage were observed by scanning electron microscope. Cutting models for different cutting approaches and various depths of cut were constructed and analyzed. The study demonstrated that the effects of shearing, tension and extrusion occur during chip formation. Various chip types, such as unit chips, splintering chips and continuous chips, were generated. Continuous pieces of chips, which are advisable for easy removal from the field of operation, were formed at greater depths of cut and tool rake angles greater than 10°. Cutting damage could be relieved with a faster recovery with clearance angles greater than 20°.

Asunto(s)

RESUMEN

Objective To investigate the biological function of IFN-λ in 7 human esophageal carcinoma cells. MethodsThe gene expression of IL-28α, IL-10β and antiviral molecule was examined with PCR. The MHC molecules expression and the profiles of cell cycle were analyzed with flow cytometer. Cell proliferation was evaluated with MTT assay. ResultsAll of esophageal carcinoma cells express the gene of II-28α and IL-10β. IFN-λ induced or augmented the gene expression of antiviral molecules, 2′5′-OAS and MxA. IFN-λ enhanced the MHC class Ⅰ molecule expression. IFN-λ inhibited the growth of esophageal carcinoma cells through the regulation of cell cycle distribution. ConclusionEsophageal carcinoma cells express the IFN-λ receptor complex. IFN-λ has the antiviral, anti-proliferative and immunoregulation activity.

RESUMEN

The valuators affect the results of performance evaluation directly.By construing the objective requirements of performance evaluation,the motivation of stakeholders,and the diversity of evaluating objects,we then set forth the necessity of valuator's multipluralism in the performance evaluation of comprehensive prevention and treatment of HIV/AIDS.We also put forward another pertinent advice that multiplural valuators should take part in general HIV/AIDS prevention and treatment evaluation,thus providing a reference for guaranteeing the results of performance evaluation,and the advancement and improvement in the performance of HIV/AIDS comprehensive prevention and treatment.