ABSTRACT
Clinical practice is the critical stage of training medical students in basic clinical quality.For the current major issues,such as lack of clinical case resources,lack of teaching conditions,and less chances of practice for students,cases library combined with medical human patient simulator is used in extern's teaching.Through this teaching,the students can touch numerous and comprehensive clinical cases,grasp clinical techniques proficiently,predominate diagnosis and treatment of common diseases in Orthopaedics efficiently by using medical human patient simulator.The effect of clinical practice teaching is improved greatly.The practice of related teaching means and methods provides a new way for the reform of the practice teaching.
ABSTRACT
<p><b>OBJECTIVE</b>To establish an canine model of femoral head osteonecrosis using an improved liquid nitrogen freezing method.</p><p><b>METHODS</b>Sixteen adult canines were divided into 4 groups at random and subjected to instant freezing of the unilateral femoral head with liquid nitrogen. The dogs were observed at 2, 4, 8, and 16 weeks after the operation for radiographic, gross and pathological changes of the femoral head.</p><p><b>RESULTS</b>Significant radiographic, gross and pathological changes occurred in the femoral head after the freezing.</p><p><b>CONCLUSION</b>Improved liquid nitrogen freezing of the femoral head provides a simple and convenient method for establishing animal models of femoral head osteonecrosis.</p>
Subject(s)
Animals , Dogs , Female , Male , Disease Models, Animal , Femur Head Necrosis , Freezing , Nitrogen , ChemistryABSTRACT
<p><b>OBJECTIVE</b>To present an established human chordoma cell line for chordoma research.</p><p><b>METHODS</b>The specimens pathologically identified as chordoma were cultured, using primary tissue culture in vitro. The surviving cells were analyzed by morphology, histochemical stain, cell cycling analysis, karyotype analysis, electron microscopic observation, heterotransplantation and study of invasive capacity in vitro.</p><p><b>RESULTS</b>The newly established cell line CM-319 has been maintained in continual cultures for over 100 generations in two years. Its morphological observation, histochemical staining properties, electron microscopic observation and heterotransplantation showed the common characteristics of chordoma. The doubling time of cells was about 33 hours. Cell cycle analysis showed: G(1) 55.6%, G(2) 21.9% and S 22.5%, G(2)/G(1) = 1.90. Chromosome analysis showed a hypotriploid feature and the success rate of heterotransplantation was 100%. It is capable of invasion in vitro.</p><p><b>CONCLUSION</b>CM-319, as a cell line derived from human chordoma cells, may serve for further studies of chordoma.</p>