BACKGROUND:Several studies have demonstrated that JAK2 kinase plays an important role in myocardial protection by ischemic preconditioning and medicine preconditioning. OBJECTIVE:To investigate the effects of exercise preconditioning on JAK2 mRNA and protein expression in the rat heart and the underlying mechanism of action. METHODS:SD rats were randomly divided into control, exhaustive, exercise preconditioning, and exercise preconditioning + AG490 groups. Rats in the control and exhaustive groups were fed routinely for 3 days. Rats in the exercise preconditioning and exercise preconditioning + AG490 groups were subjected to intermittent treadmil exercise for 3 successive days to establish exercise preconditioning animal models. Rats in the exercise preconditioning + AG490 group were intraperitonealy injected with JAK2 inhibitor AG490 at 10 minutes before exercise preconditioning. After 3 days, rats in the exhaustive, exercise preconditioning, and exercise preconditioning + AG490 groups were subjected to exhaustive treadmil exercise. Serum levels of lactate dehydrogenase and creatine kinase isoenzyme were determined. JAK2 mRNA and protein expression in the rat myocardial tissue was detected by real-time fluorescent quantitative PCR and immunohistochemistry.RESULTS AND CONCLUSION:Compared with the control group, serum levels of actate dehydrogenase and creatine kinase isoenzyme were increased, and JAK2 mRNA and protein expression in the myocardial tissue was significantly increased in the exhaustive group (P < 0.05). Compared with the exhaustive group, serum levels of actate dehydrogenase and creatine kinase isoenzyme were decreased (P < 0.05), while JAK2 mRNA and protein expression in the myocardial tissue was increased in the exercise preconditioning group (P < 0.05). Compared with the exercise preconditioning group, serum levels of actate dehydrogenase and creatine kinase isoenzyme were increased (P < 0.05), while JAK2 mRNA and protein expression in the myocardial tissue was decreased in the exercise preconditioning + AG490 group (P < 0.05). The results confirm that exercise preconditioning plays its cardioprotective role through activating JAK/STAT signaling pathway, up-regulating the expression of JAK2 mRNA and protein in the cardiac tissue and aleviating myocardial ischemia injury.

Objective To investigate the clinical efficacy of two types of duodenum-preserving pancreatic head resection (Beger procedure and Berne procedure) for chronic pancreatitis with mass in the head of the pancreas.Methods The clinical data of 46 patients with chronic pancreatitis and mass in the head of the pancreas who were admitted to the Affiliated Hospital of Guiyang Medical College from September 2008 to April 2012 were retrospectively analyzed.There were 24 patients received Beger procedure (Beger group),and 22 received Beme procedure (Berne group).The complications,life quality and pain after the operation were evaluated.Patients were followed up via phone call and out-patient examination till April 2013.The measurement data were analyzed using the Mann-Whitney U test,and the constituent ratios were compared using the chi-square test.Results The operation time and volume of blood loss were (377 ± 21) minutes and (746 ± 129) mL in the Beger group,and (323 ± 17) minutes and (577 ± 111)mL in the Berne group,with significant difference between the 2 groups (U=14.0,88.0,P ＜0.05).Four patients in the Beger group and 1 in the Berne group were complicated with pancreatic leakage,with no significant difference between the 2 groups (x2=0.714,P ＞ 0.05).The scores of life quality evaluation (physical condition,work capacity,cognitive ability,emotion,social competence and overall life quality) were 82 ± 14,74±24,90 ± 18,78±20,83 ± 18,73 ± 18 in the Beger group,and 79 ± 16,71 ±20,92 ±21,76 ± 18,80 ±21,70 ± 16 in the Berne group,with no significant difference between the 2 groups (U =177.5,183.5,187.5,178.0,189.5,192.0,P ＞ 0.05).The scores of symptom evaluation (fatigue,nausea and vomitting,pain,anorexia,dyspnea,sleep disorders,obstipation,diarrhea,financial worries) were 28 ± 16,24 ± 10,20±12,23 ± 14,4 ± 1,32 ± 12,6 ±2,18 ± 14,36± 18 in the Beger group,and 26 ± 18,26 ±20,22 ± 16,26 ± 16,3 ± 1,30 ± 10,5 ± 1,16 ± 12,38 ± 20 in the Berne group,with no significant difference between the 2 groups (U=194.5,215.5,182.5,180.5,213.0,199.0,195.0,184.5,181.5,P＞0.05).In the Beget group,19 patients did not have acute onset of pain,and 5 patients had acute onset of pain once a year; 6 patients were administered antalgesic occasionally.In the Berne group,20 patients did not have acute onset of pain,and 2 patients had acute onset of pain once a year; 4 patients were administered antalgesic occasionally,with no significant difference between the 2 groups (x2=0.485,0.041,P ＞ 0.05).All the patients were followed up,and the median time of follow-up was 36.3 months.No perforation of duodenum and steatorrhea was observed.No patient died perioperatively.Conclusion The clinical efficacy of the Berne procedure is similar to that of the Beger procedure,while the Berne procedure has advantages of easy manipulation and less operation time.

Currently,with the increasingly expanded enrollment of postgraduates and the development of postgraduate education,it is imperative to strengthen ideological and political education. This review analyzes the present status and the existing problems of the postgraduates ideological and political education. Besides,the author proposes concrete countermeasures from the following perspectives:reformation of the ideological and political education system,construction of education group,strengthening the role of the tutor and emphasizing non-intelligence factors and practical teaching notion.

Objective:To observe the clinical effect of Desensitizer Oravive combined Er:YAG laser irradiation on dentin hypersen-sitivity.Methods:240 molars in 86 patients with dentin hypersensitivity were divided into 2 groups(n =1 20).In control group De-sensitizer Oravive was applied to the teeth surface for 30 s;in combination group the teeth surfaces were treated by Er:YAG laser irra-diation for 60 s,and then by Desensitizer oravive for 30 s.Each tooth was treated only once.Pain and pain relief were evaluated by VAS before treatment and immediately,4,8 and 1 2 weeks after treatment.Data were statistically analyzed.Results:Before treat-ment,VAS showed no significant difference between the groups(P >0.05).Both groups exhibited lower VAS after treatment(P <0. 05),VAS values were lower(P <0.05)and the effective rate was higher in the combination group than those in the control group at each treatment stage(P <0.05).Conclusion:Desensitizer Oravive combined with Er:YAG laser is more effective than Desensitizer Oravive in the treatment of dentin hypersensitivity.

Objective To prepare a targeted ultrasound micro bubble,which carried the HSV-TK gene,and investigate the in vitro target searching ability of the micro bubbles and inhibitory effect on the proliferation of HepG2 cells.Methods Ultrasonic micro bubbles were prepared by mechanical vibration method,construction of targeted HSV-TK ultrasound micro bubbles by biotin affinity bridge construction.To detect the general characteristics of ultrasound micro bubbles,and to test its effect on the proliferation of HepG2 cells in vitro.Results HSV-TK targeted ultrasound microbubbles more gathered on the surface of HepG2 cells,through detection of PCNA and MTT,it was found that the proliferation of gene targeting microbubble group was obviously decreased,cell apoptosis increased significantly,Cells invade experiments showed that the number of cells in genetic microbubble group (22.18 ± 2.01) decreased significantly compared with the control group and the nontargeted group,can effectively inhibit the proliferation and invasive ability of HepG2 cells.Conclusion Targeted ultrasound microbubble carrying target gene have better inhibitory effect on HepG2 cells in vitro.

Objective To evaluate the results of modified Ludloff osteotomy for the treatment of severe hallux valgus. Methods Fifty six patients (63 feet) with severe hallux valgus were treated with modified Ludloff osteotomy in combination with other procedures during 1999-2000. There were three males (3 feet) and fifty three females(60 feet); the average age of the patients was 46 years old (range from 16 to 65 years old). The severe hallux valgus patients whose first intermetatarsal angles were larger than 16? were treated with modified Ludloff osteotomy. In addition to modified Ludloff osteotomy, combined Reverdin osteotomies were performed in 4 feet, and Akin osteotomies in another three. All patients were followed up for an average of 10 months (6 to 18 months), and evaluated with Maryland clinical rating systems of AOFAS. Weight bearing X-ray films were taken and measured as well. A comparison study was made between the commonly used osteotomies. The advantages and disadvantages as well, of modified Ludloff osteotomy, were evaluated.Results There was no nonunion, delayed union or infection. Based on hallux metatarsophalangea interphalangeal scale of Maryland rating system, 41 feet (65%) were in the score range from 90-100, 17 feet (27%)80-89, 5 feet (8%) 70-79. The rate of excellent or good was 92%. Conclusion Modified Ludloff osteotomy has the advantages of less shortened metatarsal, rapid healing, ability to correct deformity and earlier weight-bearing. It is a perfect procedure for severe hallux valgus patients whose first intermetatarsal angles are larger than 16?, but their first metatarsophalangeal joints are without signs of osteoarthritis.

[Objective] Study effect of Yun-Pi Prescription on regulating the immune function,approach the mechanism of Yun-Pi Prescription on how to enhance immune function.[Method]All the mice were divided into groups: the normal group,the model group,the positive control group treated with Xiao Shi Jian Er Syrup,and Yun-Pi Prescription treatment groups including high,middle and low dose;determine the index number of immune organ,phagocytic count and phagocytize activity of normal mice.[Results]The high and middle dose of Yun-Pi Prescription can obviously enhance the phagocytic count and phagocytize activity,Yun-Pi Prescription has an up-regulation effect on immune function.

Objective:To assess the risk of coal pneumoconiosis and measure the gross premium rate of coal pneumoconiosis liability insurance. Methods: Based on the data related to pneumoconiosis risk from published materials in different provinces, it used pure premium method to measure the gross premium rate and made province-specific rate tables of this liability insurance according to risk classification. Results: Rate tables of Chongqing, Shaanxi, Shanxi, Shandong, Henan and Anhui were made according to type of work and form of coal’s ownership. Conclusion: The risks of coal pneumoconiosis among different provinces are very different. It’s necessary to make province-specific rate tables when developing business of coal pneumoconiosis liability insurance for different provinces.

Objective:To study the ultrastructural changes of the junctional epithelial after dental preparation. Methods: Junctional epithelium (JE) of left premaxillary teeth was detached by diamond bur in 8 rabbits (group 1) and by surgical knife in another 8 rabbits (group 2). JE of the right teeth without treatment was used as the controls. 4 animals in each group were sacrificed 1 and 2 weeks after operation respectively.Samples were prepared for transmission electron microscope observation.Results: In the two tested groups reattachment was observed 2 weeks after operation,degeneration of mitochondria in JE cells and destruction of basement membrane were observed. No significant difference was observed between group 1 and group 2.Conclusion: Dental preparation may result in ultrastructural changes of JE cells.

Objective To find a new method for quality control of polysaccharides by establishing the fingerprint profiles of polysaccharides extracted from Guifu Dihuang Wan. Methods The polysaccharides extracted from Guifu Dihuang Wan were hydro-lyzed partially under appropriate hydrolysis condition with acid,and the fingerprint profiles of the hydrolyzates was obtained by HPLC. Microsoft Excel 2002 was applied for calculating the similarity of fingerprint profiles,and informatton analysis of these profiles was performed by a software for evaluating fingerprint profiles of traditional Chinese medicine. Results Fingerprint profiles of the hydroly-zates of polysaccharides from 10 of Guifu Dihuang Wan products,produced by different manufacturers,were obtained. It was observed that the similarity of eight products was greater than 0.99,while the similarity of the other two was 0.92 and 0.94,respectively. Con-clusion This method is technically feasible for the quality control of polysaccharides from Guifu Dihuang Wan.