Aimed at the current plight of medical students' professionalism education,such as ignoring the top -level design and the overall plan but emphasizing practice,ignoring the permeability of professional spirit but emphasizing the impartation of professional knowledge,ignoring humanities but emphasizing professional issues in curriculum setting,Capital Medical University advocated the all-dimensional education philosophy implenented by all staff through the whole process,made top-level design scientifically for medical students' professionalism education.The university strengthened professionalism through teaching,permeated professionalism through a series of educational activities,consolidated professionalism through clinical practice,and thus to strengthen the cultivation of medical students' professionalism and realize scientific education by all staff and throughout the whole process.

Objective To evaluate dose variations induced by gravity of multi-leaf collimator to provide references for clinical intensity-modulated radiotherapy.Methods Two-dimensional dose distributions in the central plane of IMRT fields were measured by use of a 2D ion chamber array.All measurements were repeated at two collimator angles (C=0 and 90°),for each of the following gantry angles:G=0 and 270°.Comparisons were made to dose distributions generated at G=0°and their differences were analyzed using gamma index analysis (3％/3 mm and 1％/1 mm).Results Under the radiation field of 10 cm×10 cm,the gamma passing rate was higher than 99％ for 3％ 3 mm anch close to 95％ for 1％/1mm Under a 3％/3mm error standard,the average matching rate for step & shoot fields was (96.46±0.33)％ and for DMLC fields was (94.67±0.54)％ at C=0°;The average matching rate for step & shoot fields was (94.59±0.47)％ and for DMLC fields was (92.60±0.52)％ at C=90°.Under a 1％/1mm error standard,the average matching rate for step & shoot fields was (89.83 ±1.06)％ and for DMLC fields was (85.84±0.57)％ at C=0°;The average matching rate for step & shoot fields was (86.91 ±1.71)％ and for DMLC fields was (83.89±0.69)％ at C=90°.Concusion MLC weight effect affects IMRT delivery dose,and DMLC fields are more sensitive to gravity than step & shoot fields.

Objective To explore the value of an innovative teaching model which combined problem based learning (PBL) method with case based learning (CBL) method in clinical oncology Teaching.Methods 68 students were divided into the combinational teaching group (30 cases) and the LBL group (38 cases).The combinational teaching group was taught by PBL method combined with CBL method, and this dual track teaching was based on cases and problems.The traditional teaching group was taught by LBL method.The teaching effect was evaluated by students' questionnaire survey and test score.SPSS 13.0 was used to two groups to do t test for statistical analysis in test score and x2 test for degree of satisfaction.Results In the final examination, the score of non-case test of combinational teaching group was similar to that of traditional teaching group (50.30 ± 7.19 vs.52.04 ± 8.01, P=0.358).The combinational teaching group had significant improvement in case analysis test (35.76 ± 5.28 vs.31.80 ± 5.16), and the difference was statistically significant (P=-0.003).In the course of teaching satisfaction survey, the dual track teaching group, compared with the conventional teaching group, has a better effect on self study ability, communication skills, communication skills, and higher satisfaction for teaching, and more willing to continue to carry out teaching (P＜0.05).Conclusion The PBL+CBL combinational teaching model can make a great contribution to improving the teaching quality and satisfaction, and worthy of being popularized and applied.

Objective To understand the status of the life mcaning among medical students.Methods Totally 300 students in our school were measured by the scale of purpose in life test (PIL)to analyze the status and influencing factors of life meaning.The questionnaire data were analyzed by using two independent samples t-test,One-way ANOVA and multiple linear regression.Results The average score of the life meaning survey of medical students was 84,the life goal and life value dimension scores were relatively high and the life attitude and life independent dimension scores were low.Meanwhile,the life mean in scores were higher in senior students than in junior students ( P =0.003 ),higher in undergraduate students than in college students (P =0.021 ),higher in students from urban cities than in students from rural areas ( P =0.004),higher in student leaders than in non student leaders (P =0.001 ),higher in students liking their majors than in students disliking their majors (P =0.003).Conclusions The formation of medical students' life meaning is influenced by a variety of factors.Educators need to seize the important period of students' growth and launch some targeted educational activities.Meanwhile,in order to enhance the medical students' life meaning,it is also necessary to consolidate the professional education,increase students' self-identity and guide them to correctlv view social problems.

The chronic-hypoxia-resistant gastric cancer cell line was established, and its biological characteristics were explored and compared with the parental cell line. Gastric cancer cell lines were cultured under the degressive oxygen concentration. Cell doubling time was calculated by cell counting method. Chemo-resistance ability of cells was tested by MTT assay. Irradiation tolerance of cells was evaluated by colony forming method. Cell cycle distribution was tested with flow cytometry. Invasive ability was tested by Transwell method. The expression levels of GLUT-1 and HIF-1α were detected by using Western blot. MNK45/HYP cells successfully survived under the 1% concentration of oxygen and its cell doubling time was 35.01±1.02 h, while that of MNK45 was 27.35±0.83 h (P<0.01). The percentage of MNK45/HYP cells in G(0)/G(1) stage was (58.3±6.1)%, and that of MNK45 cells was (42.2±6.0)% (P<0.05). Comparing with the parental cells MNK45, drug resistance indexes of 5-Fu, PTX, OXA, Sn38, GEM and VP16 in MNK45/HYP cells were respectively 5.3, 1.3, 3.6, 2.2, 4.8 and 4.4. Colony forming ability of MNK45/HYP cells after irradiation was also significantly higher than MNK45 cells. The invasive number of MNK45/HYP cells was 107.7±17.5, while that of MNK45 cells was 59.0±9.9. The expression levels of GLUT-1 and HIF-1α in MNK45/HYP cells were significantly higher than those in MNK45 cells. MNK45/HYP cells hold biological characteristics of hypoxia tumor with good tolerance to chronic hypoxia, and can be used for the research of solid tumor under chronic hypoxia condition.

The benefit achieved by concurrent chemoradiotherapy (CCR) and sequential chemoradiotherapy (SCR) vs radiotherapy (RT) alone for patients with stage II-IVa nasopharyngeal carcinoma (NPC) was compared. A total of 113 patients with stage II-IV a NPC were allotted into CCR group (n=38), SCR group (n=36) and RT alone group (n=39). All patients were irradiated with the same RT technique to ≥66 Gy at 2 Gy per fraction, conventional 5 fractions/week in all groups. The CCR group received concurrent chemotherapy of weekly cisplatin for 7 weeks, and the SCR group received neoadjuvant and (or) adjuvant chemotherapy. The results showed that the 3- and 5-year overall survival rate was significantly higher in CCR group than in RT alone group (92.16% vs 61.54%, 81.58% vs 51.28%, P<0.005). The median survival time was significantly longer in CCR group than in RT alone group (67.8 months vs 52.7 months, P<0.005). It was concluded that CCR could significantly improve overall survival rate, progression-free survival rate, and median survival time when compared with RT alone.

The inhibitory effects of Endostar in combination with radiotherapy in BALB/c nude mice model of human CNE2 nasopharyngeal carcinoma and the mechanism were investigated. In nude mice model of CNE2 nasopharyngeal carcinoma, the inhibitory rate and the sensitizing enhancement ratio (E/O) were calculated according to the tumor volumes in different groups. The expression of microvascular density (MVD) in tumor tissues was examined by using immunohistochemistry staining. The transcription of VEGF gene was detected by using RT-PCR. The inhibitory rate in Endostar+ radiotherapy group was higher than in other groups. In Endostar+radiotherapy group, the tumor volume was significantly decreased and the E/O ratio was 2.335, suggesting that Endostar could be a radiosensitizer. The expression of MVD of tumor tissues in Endostar+radiotherapy group was reduced significantly. The expression of the MVD in treatment groups was significantly different from that in control group (P<0.05). Compared to other groups, VEGF mRNA expression in Endostar+radiotherapy group was decreased remarkably. Endostar in combination with radiotherapy significantly inhibited the growth of CNE2 tumor. The combination therapy decreased the expression of VEGF, and inhibited tumor angiogenesis and proliferation. When combined with radiotherapy, Endostar acted as a radiosensitizer.

The chronic-hypoxia-resistant gastric cancer cell line was established,and its biological characteristics were explored and compared with the parental cell line.Gastric cancer cell lines were cultured under the degressive oxygen concentration.Cell doubling time was calculated by cell counting method.Chemo-resistance ability of cells was tested by MTT assay.Irradiation tolerance of cells was evaluated by colony forming method.Cell cycle distribution was tested with flow cytometry.Invasive ability was tested by Transwell method.The expression levels of GLUT-1 and HIF-1α were detected by using Western blot.MNK45/HYP cells successfully survived under the 1％ concentration of oxygen and its cell doubling time was 35.01±1.02 h,while that of MNK45 was 27.35±0.83 h (P＜0.01).The percentage of MNK45/HYP cells in G0/G1 stage was (58.3±6.1)％,and that of MNK45 cells was (42.2±6.0)％ (P＜0.05).Comparing with the parental cells MNK45,drug resistance indexes of 5-Fu,PTX,OXA,Sn38,GEM and VP16 in MNK45/HYP cells were respectively 5.3,1.3,3.6,2.2,4.8 and 4.4.Colony forming ability of MNK45/HYP cells after irradiation was also significantly higher than MNK45 cells.The invasive number of MNK45/HYP cells was 107.7±17.5,while that of MNK45 cells was 59.0±9.9.The expression levels of GLUT-1 and HIF-1α in MNK45/HYP cells were significantly higher than those in MNK45 cells.MNK45/HYP cells hold biological characteristics of hypoxia tumor with good tolerance to chronic hypoxia,and can be used for the research of solid tumor under chronic hypoxia condition.

The benefit achieved by concurrent chemoradiotherapy (CCR) and sequential chemoradiotherapy (SCR) vs radiotherapy (RT) alone for patients with stage Ⅱ-Ⅳa nasopharyngeal carcinoma (NPC) was compared.A total of 113 patients with stage Ⅱ-Ⅳa NPC were allotted into CCR group (n=38),SCR group (n=36) and RT alone group (n=39).All patients were irradiated with the same RT technique to ≥66 Gy at 2 Gy per fraction,conventional 5 fractions/week in all groups.The CCR group received concurrent chemotherapy of weekly cisplatin for 7 weeks,and the SCR group received neoadjuvant and (or) adjuvant chemotherapy.The results showed that the 3- and 5-year overall survival rate was significantly higher in CCR group than in RT alone group (92.16％ vs 61.54％,81.58％ vs 51.28％,P＜0.005).The median survival time was significantly longer in CCR group than in RT alone group (67.8 months vs 52.7 months,P＜0.005).It was concluded that CCR could significantly improve overall survival rate,progression-free survival rate,and median survival time when compared with RT alone.

The inhibitory effects of Endostar in combination with radiotherapy in BALB/c nude mice model of human CNE2 nasopharyngeal carcinoma and the mechanism were investigated.In nude mice model of CNE2 nasopharyngeal carcinoma,the inhibitory rate and the sensitizing enhancement ratio (E/O) were calculated according to the tumor volumes in different groups.The expression of microvascular density (MVD) in tumor tissues was examined by using immunohistochemistry staining.The transcription of VEGF gene was detected by using RT-PCR.The inhibitory rate in Endostar+radiotherapy group was higher than in other groups.In Endostar+radiotherapy group,the tumor volume was significantly decreased and the E/O ratio was 2.335,suggesting that Endostar could be a radiosensitizer.The expression of MVD of tumor tissues in Endostar+radiotherapy group was reduced significantly.The expression of the MVD in treatment groups was significantly different from that in control group (P＜0.05).Compared to other groups,VEGF mRNA expression in Endostar+radiotherapy group was decreased remarkably.Endostar in combination with radiotherapy significantly inhibited the growth of CNE2 tumor.The combination therapy decreased the expression of VEGF,and inhibited tumor angiogenesis and proliferation.When combined with radiotherapy,Endostar acted as a radiosensitizer.