The seven-year system in medical education is a new teaching model of cultivating the high-level medical talents to meet the need of construction of socialist health modernization of our country.As a student having had medical study for two years,I realize some advantages and shortcomings existing in the class education.So I have made analysis of the current conditions of its basic medical education and put forward some proposals,hoping to provide help for the seven-year teachings in the undergraduate courses.

Background It has been proved that as an important adhesion protein of extracellular matrix,osteopontion (OPN) can affect tumor neovascularization.Some new researches showed that anti-OPN antibody plays a role in regulating the neovascular vessel formation.Choroidal neovascularization (CNV) has the same structure with tumor neovascularization,but whether anti-OPN antibody restricts new vessel formation is unclear.Objective This study was to investigate the inhibitory effect of anti-OPN antibody on CNV.Methods Laser-induced CNV models were created in 40 eyes of 40 male SPF C57BL/6J mice by Argon laser photocoagulation of retinas,with the wavelength 514 nm.Thirty-six successful models were randomly divided into anti-OPN antibody group,mouse-IgG group and PBS group by the randomized number table.On the second day after photocoagulation,anti-OPN antibody of 400 μg was intraperitoneally injected in the anti-OPN antibody group,and the equivalent amount of mouse IgG and PBS were used in the same way in the mouse IgG group and PBS group.The CNV was evaluated by fundus fluorescein angiography (FFA) on the seventh days after photocoagulation.The mice were immediately sacrificed and the eyeballs were enucleated on the fourteenth day after photocoagulation,and 4 eyeballs in each group were used to observe the areas of CNV on the retinal pigmental epithelium-choroid-sclera fiat mounts,and the other 8 eyeballs of each groups were used to analyze the expression levels of OPN mRNA and vascular endothelial growth factor(VEGF) mRNA using quantitative fluorescence-PCR (QF-PCR).Results FFA showed fluorescein leakage areas around laser spots 7 days after photocoagulation,indicating that CNV appeared.The CNV areas were ([16.98±0.70] × 103) μm2,([27.13 ± 0.81] × 103) μm2 and ([35.39±2.14] ×103) μm2 respectively in the anti-OPN antibody group,mouse IgG group and PBS group,with a significant difference among the 3 groups (F =533.76,P =0.00),and the CNV area was significantly smaller in the anti-OPN antibody group compared with those of the mouse IgG group and PBS group (q =-3.95,-4.40,both at P＜0.05).No significant difference was found in the OPN mRNA expression between the antiOPN antibody group and mouse IgG group (t =-5.26,P =0.66).However,the expression of VEGF mRNA in choroidal tissue was significantly declined in the anti-OPN antibody group than that in the mouse IgG group (t =-6.74,P＜0.01).Conclusions Anti-OPN antibody suppresses the formation of CNV in laser-induced mouse model by down-regulating VEGF.

Objective To investigate the expression of Smac/DIABLO, XIAP mRNA in acute pancreatitis (AP) and the relationship with the severity in rats.Methods Fifty-four SD rats were randomly divided into three groups:sham-operation (SO) group, acute edematous pancreatitis (AEP) group and acute necrotizing pancreatitis (ANP) group.The models of AEP and ANP were induced by retrograde injection of 1％ and 3.5％ sodium deoxycholate into the pancreaticobiliary duct respectively.The specimens of pancreatic tissue at 3 h, 6 h, 12 h were collected, pathological changes of the pancreas were observed, apeptosis in pancreas were detected by TUNEL method and the expression of Smac/DIABLO, XIAP mRNA were analyzed by real-time PCR.Results Pathological changes of the pancreas confirmed the establishment of AEP and ANP.Apeptosis indexes in SO group, AEP group and ANP group were 0.67±0.82, 6.62 ±0.78 and 4.70 ±0.82, and the differences were significant (P< 0.05).The expression of Smac/DIABLO mRNA of AEP group increased with time, while the expression of ANP group decreased with time.Compared with SO group, Smac/DIABLO mRNA expressions at 6 h in AEP and ANP group were 2.41 ± 0.92 and 1.47± 0.53, and the differences were significant (P<0.05).By contrast, the expressions of XIAP mRNA in AEP group decreased with time,while the expressions in ANP group increased with time.The expressionsof XIAP mRNA at 6 h in AEP and ANP group were 5.51 ± 1.07 and 6.99 ± 1.00, and the differences were significant (P<0.05).Conclusions In acute pancreatitis, the expression of Smac/DIABLO mRNA was consistent with the apoptosis of pancreatic acinar cells, but not consistent with the severity of pancreatitis.The expression of XIAP mRNA was consistent with the severity of pancreatitis.Smac/DIABLO, XIAP mRNA is associated with regulation of apoptosis.

There were some samples collected from the Antarctic soil and South Ocean water for isolation of microorganisms and screening of their antitumor bioactivity by lethality bioassay using brine shrimp and a flow cytometric bioassay.There were 259 stains were isolated from the samples,11% of the Antarctic microorganisms showed strong antitumor activity.This result showed that the Antarctic microorganisms have a good potential in bioactive metabolites researching.

In the presence of hydrochloric acid, tetraethoxysilicane was hydrolyzed and formed silica sol. Non-labeled immunosensor was fabricated by droping the mixture solution of the silica sol and antibody of aflatoxin B_1 on the surface of glassy carbon electrode. In this work, a Fe(CN)_6~(3-/4-) phosphate buffer solution) was employed as base solution for investigating cyclic voltammetry(CV) and electrochemical impedance spectroscopic(EIS) performances of the sensor, respectively. The experimental results t indicated that because of the complex formed by the immunoreaction hindered the diffusion of Fe(CN)_6~(3-/4-) on the electrode surface, the redox peak current of the immunosensor in CV obviously decreased, and its electron transfer impedance linearly) increased with increasing the concentration of aflantoxin B_1(AFB). When the medium acidit and incubation) time were pH 6.5 and 20 min, respectively, the biggest electron transfer impedance changed value before and after the immunoreaction was obtained. Under the optimal conditions, a linear range to concentration of aflatoxin B_1 was 1-10 μg/L with a detection limit of 0.1 μg/L(S/N=3). Proposed method is of high sensitivity and stability, it has been successfully applied to determine AFB_1 in maize, rice and peanut.

Objective We investigated interleukin (IL)-23 that might play a role in the pathogenesis of rheumatoid arthritis (RA) and whether it was correlated with disease activity and clinical manifestations in axial spondyloarthritis (SPA).In addition, the Spondyloarthritis Research Consortium of Canada (SPARCC) scores was used to examine whether recombinant human tumor necrosis factor-α receptor Ⅱ IgG Fc fusion protein for injection (rhTNFR:Fc) was effective for the reduction of magnetic resonance imaging (MRI)-proven sacroiliac joint (SIJ) inflammation.Methods The serum IL-23 levels of etanercept and conven-tional treatment groups were measured using enzyme-linked immunosorbent assay kits.At the same time, SIJ MRI SPARCC score levels were assessed by MRI, the change of clinical indicators of patients was observed.ANOVA, repeated measure data of ANOVA and Spearman's correlation analysis were used for statisical analysis.Results ① The basal serum IL-23 levels of the Etanercept group were (34.2±1.8) pg/ml and those of the conventional treatment group were (34.1 ±1.8) pg/ml (F=1 073.790, P=0.991), both were significantly higher than the healthy control group (18.1±0.8) pg/ml (P=0.005).After treatment, serum IL-23 levels of the rhTNFR: Fc treatment and conventional treatment group were (24.5 ±1.7) pg/ml and (25.2±1.7) pg/ml (F=232.488, P=0.242), (19.2±0.8) pg/ml and (21.6±1.3) pg/ml (F=114.135, P=0.025), (19.0±0.8) pg/ml and(19.4± 0.8) pg/ml (F=23.374, P=0.085) respectively.A significant decrease was observed in the two groups and the serum level of IL-23 of the rhTNFR:Fc group was lower than that of the conventional group at week 12.② SIJ MRI SPARCC scores of the rhTNFR:Fc group and the conventional drugs group were (20.1± 1.2) scores and(20.7±1.5) scores (F=2003.660, P=0.191), (12.5± 0.8) scores and (15.4±0.9) scores (F=1 680.430, P=0.004), (8.8±0.9) scores and (12.8± 0.9) scores (F=972.877, P=0.002), the scores of two group were significantly decreased after treatment.At week 12, 24 of the treatment, the rhTNFR:Fc group scores were lower than the conventional drugs group.③ The serum IL-23 levels, SLJ MRI SPARCC scores and clinical index (ESR, CRP, PGA, BASDAI, BASFI, BASMI and number of painful joints) were not correlated (P＞0.05), the SIJ MRI SPARCC scores and clinical indicators were not correlated (P＞0.05).Conclusion ① The serum IL-23 levels of the rhTNFR:Fc are higher than healthy controls.② rhTNFR:Fc treatment could significantly decrease IL-23 levels and improve the sacroiliac joint inflammation compared to conventional treatment.③ SIJ MRI is a good assessment method for the detection of SpA sacroiliac joint inflammation.

Objective To study the correlation between 5-serotonin transporter ( 5-HTT) gene pol-ymorphism and the first episode major depressive disorder ( MDD ) and cognitive function in adolescent. Methods 5-HTT genotype and allele were detected by polymerase chain reaction ( PCR) amplification of 76 patients with first episode of MDD and 73 normal controls. Case control method was used to analyze the correlation between different genotypes and the onset, the clinical features, and cognitive function. Result-s There was no significant difference between 5-HTTLPR genotype frequencies for the 41 cases of type S/S (53.9%),27 cases of type L/S(35.5%),8 cases of type L/L(10.5%)of case group and 5-HTTLPR geno-type frequencies for the 38 cases of type S/S(52.1%),18 cases of type L/S(24.7%),17 cases of type L/L (23.3%) of control group(P>0.05).Patients with S/S type,L/S type had significantly higher sleep scores than those of patients with type L/L(P=0.005,P=0.001). Agitation score in patients with S/S type group was significantly higher than that in patients with S/L,L/L(P=0.000,P=0.001);patients with S/S inferior-ity scores were significantly lower than those of patients with S/L,L/L(P=0.002,P=0.006). There was no significant difference in cognitive function among three groups. Conclusions In Chinese Han population, there may be no direct association between 5-HTTLPR gene polymorphism and susceptibility to MDD and its cognitive function in adolescents. S/S and L/S patients may be prone to sleep problems,type S/S patients may be prone to irritability and type L/L patients may be prone to inferiority.

Objective To investigate the effect of total flavonoid of Herba Pyrolae(TFHP) on the changes of ECG in rats with acute myocardial ischemia as well as the mechanism of the action.Methods Acute myocardial ischemic model was established by intravenous injection of pituitrin in rats,and ECG was recorded.Acute myocardial infarction model was established by the ligation of left descending coronary artery in rats,and serum level of nitric oxide(NO) and free fatty acid(FFA) was determined with spectrophotometrical method besides ECG.Results In comparison with the model controls,TFHP antagonized the decreased T wave by pituitrin and ligating coronary artery,and increased NO level and reduced FFA concentration in the serum of rats with acute myocardial ischemia.Conclusion TFHP protects the myocardium from ischemic injury possibly through increasing NO release and decreasing FFA production.

Objective To investigate the effects of epidural spinal cord electrical stimulation (ESCES) on spinal cord reflexes in normal adult rats, and to find out where and how the spinal cord reflexes are generated. Methods Ten adult female Sprague Dawley rats were anaesthetized and an electrode was placed at the S, spinal cord segment. Single electric pulses with 200 μs pulse width and voltages of 400 mV, 600 mV and 1200 mV were used in the ESCES. 1200 mV voltages with 50 Hz, 60 Hz, 80 Hz, 100 Hz frequency were also tested. EMG signals were re-corded with concentric needle electrodes in the rats' semitendinosus muscles to observe the characteristics of spinal cord reflexes. Results The voltage threshold for generating semitendinosus muscle response was 300 mV. The three ESCES voltages induced 2 kinds of spinal cord reflexes. The 400 mV and 600 mV stimulation induced spinal cord reflexes with short latency (5.27±0.36 ms and 5.19±0.67 ms respectively). The 1200 mV stimulation volt-age induced spinal cord reflexes with long latency (2.57±0.23 ms). Spinal cord reflexes could be generated by 50 Hz, 60 Hz, 80 Hz, and 100 Hz ESCES. At the higher frequencies, spinal cord reflexes declined late in the ex-periments and then appeared irregular. In some of the rats, spinal cord reflexes vanished entirely late in the stimula-tion experiments. The latency and duration of the spinal cord reflexes induced by 50 Hz ESCES were (4.46 ± 1.07) ms and (7.33±1.00)ms respectively. These were significantly different from the latency and duration initia-ted by 60 Hz, 80 Hz or 100 Hz ESCES. Conclusions Different ESCES voltages induce different spinal cord refle-xes generated differently. The long latency reflexes might be monosynaptic responses mediated by dorsal root excite-ment, while the short latency reflexes might be sarcous exciting electric activity mediated by direct excitement of mo-tor neurons or motor fibers. The irregular spinal cord reflexes induced by higher frequency ESCES might be one kind of monosynaptic response. Irregularly appearing spinal cord reflexes induced by higher frequency stimulation might due to the inhibitory effect of higher frequency stimulation.

Objective To study the GPⅡb/Ⅲa gene mutations of eight glanzmann thrombasthenia(GT) pedigrees. Methods Responses of eight probands to different agonists were observed by platelet aggregation test and the amount of αⅡb and β3 was determined by flow cytometry. All the exons of Ⅱb and Ⅲ a genes were amplified by PCR followed by sequencing for mutational screening. Further analysis of the normal population excluded the possibility of mutational sites as a polymorphism. Results Eight probands showed normal PLT counts, dispersion of the platelet particles without aggregation, prolonged bleeding time and severely reduced platelet aggregation in response to the physiological agonists- ADP, epinephrine, and collagen, but relatively normal aggregation of PLT in response to ristocetin. Flow cytometry showed that all probande were Ⅰ type GT, except that proband 2 was Ⅲ type GT and proband 6 was Ⅱ type GT. The sequencing results showed that twelve different types mutations were present in eight probands, including GIOA, Gl412T, GII99A, 1525deiC, G2223T, C2671T, 2930delG, IVSI5 (-1) delG, A2334C, C1750T, 69-79del and CA70A. We were not able to detected any mutations in GP Ⅱb/Ⅲa gone on proband 3. Conclusions GT is mainly caused by GPⅡb/Ⅲa gene mutations. G10A, 69-79del, C470A,G1412T, G2223T, C2671T and 1525delC were the novel mutations causing GT.