Targeting of tumor cells is crucial for gene therapy of malignant diseases.This can be achieved by tumor targeted gene transfer or tumor specific gene expression, as well as secretion of tumor targeted therapeutic molecules by autologous normal cells.Tumor targeted gene transfer is mediated by the recognition of a class of tumor specific antigens or receptors by corresponding vector fused antibodies or ligands, while therapeutic genes can be selectively expressed in tumor cells under the control of tumor or tissue specific promoters or enhancers, as well as the induction of certain physical, chemical or physiological factors.

Objective Through the design of comprehensive experiments, the precise medical philo-sophy was put into the medical molecular biology experimental teaching, and to explore its effect. Methods Eight-year medical students of Grade 2012 and Grade 2013 in the Fourth Military Medical University were chosen as the teaching subjects. Experimental group consisted of 36 students of Grade 2013, while control group consisted of 30 students of Grade 2012. Precision medicine-based learning was applied in experimental group while traditional learning method was adopted by the control group. At the end of the course, students of two groups were implemented theoretical and experimental skills assessment; through questionnaire students were required to evaluate the effect of teaching methods and the number of two groups of students who asked questions after class greater than or equal to 1 times was counted to evaluate the students' learning enthusiasm. SPSS 15.0 software was used to make t test and Chi-square analysis for the data of the students. Results The assessment results showed that the experimental group was better than control group, especially in the section of comprehensive experimental design [(16.7 ± 2.04) vs. (13.9 ± 2.87), P=0.000]. The results from questionnaire showed that the satisfaction degree of experimental group was also higher than that of control group in many respects, including learning interests, innovation capability, knowledge mastery, cognition of precision medicine and clinical research, satisfaction with the teaching method (P<0.05). And students' learning enthusiasm and the proportion of the number of students asking questions in the experimental group were higher than the control group (P=0.000). Conclusions Precision medicine-based learning not only changes the situation of slavish imitation and passive acceptance in traditional learning, but also arouses students' interest in study and helps students to cultivate clinical thinking, which is com-mensurate to the characteristics of precision-medicine era.

Objective: To analyze influencing factors of percutaneous coronary intervention (PCI) on therapeutic effect in patients with coronary chronic total occlusions (CTO). Methods: Clinical data, lesion features and PCI therapeutic results of 65 patients with 72 CTO lesions, who received PCI in our hospital from Jan 2010 to Dec 2012, were retrospectively analyzed. Results: PCI success rate of CTO lesion was 91.67% (66/72); compared with patients with CTO occlusion 3~12 months, there was significant decrease in PCI success rate (97.78% vs. 81.48%) in those with CTO occlusion >12 months; compared with patients with occlusion length ≤15mm, there was significant decrease in PCI success rate (97.96% vs. 78.26%) in those with occlusion length >15mm; compared with patients with mouse tail-like broken ends, there was significant decrease in PCI success rate (96.55% vs. 71.43%) in those with knife cut-like broken ends, P<0.05 all; PCI failed in six lesions, in which four because guidewire failed to pass through lesions and two because balloon failed to pass through lesions; incidence rate of complications was 7.69% during PCI, there were no major adverse cardiovascular events during admission in all patients; symptoms relieving rate of angina pectoris was 90.16% after PCI. Conclusion: Success rate of percutaneous coronary intervention is related to lesion features, CTO occlusion duration etc.