Problem-based learning has gradually become an important pedagogical tool in the medical curriculum.Behaviors of PBL tutor play an unique role in teaching.A good PBL tutor must consider the following issues:ample preparing before class,awareness of learning outside the tutorial room,social congruence,dealing with the difficult student and dysfunctional group,sharing the PBL experience and seeking support or advice from peers.

Human rotavirus has been discovered since the early 1970s, which is still a primary pathogen causing infant diarrhea under the age of five. Each year about 600,000 infant died of severe body dehydration caused by rotavirus infection. Since the current rotavirus diarrhea have no specific therapeutic drugs, using vaccine to prevent rotavirus infection is an effective method. Research on a vaccine often involved in a multidisciplinary theory and technology. This article reviewed the epidemic situation of rotavirus,animal model,the body's immune response after infection, developing and using vaccine and other related issues.

Objective To explore the efficacy and safety of compound azintamide enteric‐coated tablets in the treatment of patients with dyspepsia after gastrointestinal surgery .Methods Multicenter , randomized ,double blind ,placebo‐controlled ,parallel controlled method w as applied .From January 2011 to January 2013 , of 240 patients with dyspepsia after gastrointestinal surgery from 12 hospitals in Shanghai were enrolled and divided into medicine treatment group (n= 120) and placebo control group (n= 120 ) ,received compound azintamide enteric‐coated tablets or placebo , respectively . Compound azintamide enteric‐coated tablet (100 mg) or placebo was oral taken each time ,three times per day for four weeks .Total and respective score of dyspeptic symptoms (abdominal distension ,loss of appetite ,early satiety ,belching ,nausea ,abdominal pain or abdominal discomfort) were evaluated prior to study and on the 1st , 2nd , 3rd and 4th week after treatment . On the 4th week after treatment ,the efficacy of the improvement of dyspeptic symptoms was compared between the two groups ,and the safety was also evaluated .The score of the quality‐of‐life was compared between the two groups prior to study and on the 4thweek after treatment .The t‐test was performed for comparison between measurement data ,Chi‐square test was used for count data ,and rank sum test was used for rank data .Results At one week after treatment ,the scores of abdominal distension (4 .61 ± 0 .98 ) ,early satiety (2 .87 ± 0 .64 ) ,belching (3 .03 ± 0 .58) ,abdominal pain or abdominal discomfort (3 .13 ± 0 .79) and total score (18 .32 ± 3 .44) of patients in medicine treatment group were significantly lower than those of placebo control group (8 .83 ± 1 .28、4 .28 ± 0 .61、4 .87 ± 1 .07、5 .46 ± 0 .87、29 .63 ± 5 .50) ,and the differences were statistically significant (t=28 .524、17 .400、16 .453、21 .619 and 18 .983 ,all P< 0 .01 ) . However there was no significant difference in the scores of loss of appetite and nausea (both P> 0 .05) .At 2nd ,3rd and 4th week after treatment ,respective score of dyspeptic symptoms and total score of medicine treatment group (2nd week:2.57±1.28,1.87±1.17,1.55±1.27,1.55±1.08,1.09±0.82,1.98±1.02,10.53±4.54,3rdweek:1 .42 ± 0 .60 ,1 .11 ± 0 .45 ,0 .94 ± 0 .37 ,0 .94 ± 0 .41 ,0 .79 ± 0 .31 ,1 .42 ± 0 .55 ,6 .52 ± 2 .41 ,4th w eek:1.13±0.51,0.46±0.12,0.58±0.13,0.38±0.16,0.30±0.07,0.81±0.33,3.65±1.06)wereall significantly lower than those of placebo control group (2nd week:8 .50 ± 2 .61 ,3 .78 ± 2 .01 ,4 .08 ± 2 .14 , 4.73±2.64,2.27±2.13,4.91±2.24,28.25±8.86,3rdweek:7.92±2.51,3.68±1.76,4.08±1.86, 4.71±1.77,2.14±0.83,5.01±1.31,27.54±8.09,4th week:7.63±2.37,3.67±1.63,3.92±2.08, 4 .66 ± 2 .95 ,2 .14 ± 1 .65 ,4 .67 ± 2 .34 ,and 26 .68 ± 7 .45) ,and the differences were statistically significant (all t=0 .000 ,all P<0 .01) .At 4th week after treatment ,the total efficacy of total score improvement of dyspepsia symptoms in medicine treatment group was 86 .21% (100/116) ,which was significantly better than that of placebo control group (39 .16% (47/120)) ,and the difference was statistically significant (Z=9 .464 ,P<0 .01) .The total score of quality of life in medicine treatment group was significantly lower than that of placebo control group (12 .24 ± 4 .30 and 22 .13 ± 6 .18) ,and the difference was statistically significant (t=14 .225 , P< 0 .01 ) .No adverse events was observed in both groups during treatment period . Conclusion Compound azintamide enteric‐coated tablets may effectively improve dyspeptic symptoms and quality of life in patients with dyspepsia after gastrointestinal surgery ,and with good safety .

Objective To evaluate the efficacy and safety of compound azintamide enteric-coated tablet in the treatment of patients with post-cholecystectomy dyspepsia.Methods A multicentre,randomized,double-blinded,placebo-controlled trail was conducted.A total of 120 patients with post-cholecystectomy dyspepsia were divided into azintamide group (n=60) and placebo group (n＝60),taking compound azintamide enteric-coated tablet or placebo 100 mg each time,three times per day for 28 days.The score of each dyspeptic symptom (abdominal distension,loss of appetite,early satiety,belching,nausea,abdominal pain or abdominal discomfort) and total score of dyspepsia were evaluated prior to study and on the 7th,14th,21st and 28th day after treatment.The efficacy of the improvement of dyspeptic symptoms was compared between the two groups on the 28th day after treatment and the safety was evaluated.The score of the quality-of-life was compared between the two groups prior to study and on the 28th day after treatment.The t-test or chi-square test was performed for statistical analysis.Results The scores of abdominal distension,belching,nausea,abdominal pain or abdominal discomfort and the total score of azintamide group on the 7th day after treatment (5.7±3.1,3.5±2.1,0.3±0.1,3.3±1.7 and 17.9±9.6) were significantly lower than those prior to study (8.9±5.3,5.3±2.5,0.9±0.4,4.5±3.7,24.3±14.5;t=3.758,3.976,10.494,2.125 and 2.654,allP＜0.05).On the14th,21st and28thday after treatment in azintamide group,the score of each dyspeptic symptom and the total score were lower than those prior to study.The symptom of abdominal distension significantly improved on the 7th,14th,21st and 28th day after treatment in placebo group,and the score of early satiety and total score of dyspepsia were significantly lower on the 28th day after treatment compared with those before treatment.In azintamide group,the total efficacy rate was 66.7％ (40/60),which was higher than that of placebo group (38.3％,23/60) and the difference was statistically significant (x2 =9.653,P ＜ 0.01).On the 28th day after treatment,SF-NDI of azintamide group was 4.4±3.4,which was significantly lower than that of placebo group (9.6±6.0) and the difference was statistically significant (t=5.450,P＜0.01).In azintamide group there was one patient with rash on the 7th day after treatment,and in placebo group there was one patient with headache on the 14th day after treatment.The symptoms disappeared seven days after medicine withdrawal.Conclusion Compound azintamide enteric-coated tablet effectively improves dyspeptic symptoms and quality of life in patients with post-cholecysteetomy dyspepsia and has good safety.

Objective To investigate the activation and clinical significance of the mammalian target of rapamycin (mTOR) pathway related protein and eukaryotic translation factor 4E-binding protein 1 (4E-BP1) in gastric cancer.Methods The activation of mTOR and 4E-BP1 in gastric cancer tissues of 38 surgical patients were detected by immunohistochemical method.The differences of phosphorylated mTOR and 4E-BP1 expression among cancerous tissues,para-cancerous tissues and normal gastric mucosa tissues and dinicopathological variables were analyzed by Chi square test and Kruskal-Wallis test.Results The positive expression rate of phosphorylated mTOR in the gastric cancerous tissues was significantly higher than that of para-cancerous tissues and normal tissues [71.1％ (27/38),50.0 ％ (19/38) and 44.7 ％ (17/38),x2 =11.031,P =0.026].The positive expression rate of downstream protein 4E-BP1 in the gastric cancer tissues was also significantly higher than that of paracancerous tissues and normal tissues [68.4％(26/38),57.9％(22/38) and 28.9％ (11/38),x2 =13.943,P=0.007].There was no correlation between phosphorylated mTOR and 4E-BP1 expression and tumor Lauren's sub-type,infiltration,differentiation degree,lymph node metastasis and patient's age.There was statistical significant difference between activated 4E-BP1 expression and tumor size in gastric cancer (H=3.86,P＜0.05).Conclsions mTOR pathway was over activated in gastric cancer.There was difference between phosphorylation degree of its downstream protein 4E-BP1 and the tumor size.

Codon usage bias is an important characteristic of genetic information transfer in organisms. Analysis of codon usage bias of different species is important for understanding the rules on genetic information transfer. The previous method for analysis of codon usage bias is mainly based on genomic data. However, this method is greatly limited, because the genome sequences of higher organisms are still not available up to now. In this study, we found that we could obtain the same optimal codons of Ganoderma lucidum (Curtis: Fr.) P. Karst based on its whole genomic data or large-scale transcriptomic data from its liquid-cultured hyphae, primordium and fruiting body, separately. This result indicated the feasibility to understand the codon usage bias based on the large-scale transcriptomic data. By calculating the proportion of rare codons of Escherichia coli and Saccharomyces cerevisiae in 26 terpene synthases (TS) of G. lucidum, we found that the rare codons of S. cerevisiae have a higher proportion in TS genes, while the rare codons of E. coli have relatively lower, suggesting that the TS genes of G. lucidum are possibly more difficult to be expressed in S. cerevisiae than in E. coli. Chemical synthesis of TS genes according to the yeast optimal codons will be an effective way to solve the problem on the mismatch of gene codon bias between the foreign genes and the host strain.

Salvia miltorrhiza Bge. is a perennial deciduous flowering plant. Its medicinal root and rhizomes part is widely used in the treatment of various diseases. In this study, bioinformatics analysis was performed to identify 4832 genome SSR loci with length longer than or equal to 40 bp from the draft genome assembly of S. miltorrhiza. The re-sults showed that the dinucleotide repeat motifs and trinucleotide repeat motifs constitute the main types of genome SSR loci, accounting for 37.3% and 61.3% respectively. SSR types enriched with A/T bases showed significantly higher abundance than other types, including AT/TA AAT/ATT, ATA/TAT, TAA/TTA, accounting for 30.5%, 21.6%, 17.1%, 20.4% of the total number of SSR loci, respectively. 1079 primer pairs were designed for these genome SSR loci. These primers can be used for genomic diversity analysis, genetic map construction, genetic marker screening. These data could lay the foundation for population genetics and genomics research of S. miltorrhiza.

Cytochrome P450 (CYP450) is a key element in the Ganoderma triterpenoid biosynthetic pathway. The catalytic reaction process for CYP450 requires NADPH / NADH for electron transfer. After searching the genome dataset of Ganoderma lucidum, the unique sequence encoding CYP450 and NADPH were discovered, separately. The open reading frames of GLCYP450 and GLNADPH were cloned separately using RT-PCR strategy from G lucidum. The appropriate restriction enzyme cutting sites were introduced at the 5' and 3' ends of gene sequence. The genes of GLCYP450 and GLNADPH were recombined into the yeast expression vector pESC-URA, leading to the formation of the yeast expression plasmid pESC-GLNADPH-GLCYP450. This study provides a foundation for researching Ganoderma triterpene biosynthesis using the approach of synthetic biology.

Objective To explore the localization diagnosis method of lumbar intervertebral foramen stenosis by multi-di-mensional MRI scans of lumbar nerve roots. Methods Twenty-one patients with lumbar intervertebral foramen stenosis were fol-lowed up from June 2006 to June 2011 postoperatively, 10 cases of male, 11 cases of female;36 to 65 years old, average 45.6 years. The medical history is six to thirty six months, an average of 9.4 years;5 cases have low back pain with unilateral leg pain and 16 cases showed unilateral leg pain only. The height of intervertebral space and foramen intervertebrale were measured on the X-rays of lumbar lateral position. Lumbar nerve roots MR imaging at the position of axial, coronal and sagittal scan were performed separately to the patients who were clinically suspected to suffer from lumbar intervertebral foramen stenosis. A definitive diagno-sis of the location of nerve root compression and structural changes surrounding the nerve root can be obtained. Surgical operation was performed to confirm the accuracy of the MRI imaging diagnosis. Results There were 9 cases of lumbar intervertebral fora-men stenosis caused by lumbar disc herniation. The other 12 cases are caused by zygapophyseal joint hyperplasia. All cases of lumbar intervertebral foramen stenosis located at the low back. By comparing MR images of lumbar intervertebral foramen stenosis with surgical procedure,the surgical observation of 21 patients completely coincided with the preoperative localization diagnosis, coincidence rate was 100%(21/21). After surgical treatment, 20 cases achieved a complete remission of leg pain and 1 case was not satisfactory. Conclusion MRI imaging at the position of axial, coronal and sagittal scan for lumbar nerve roots were useful to rigorous localization diagnosis of lumbar intervertebral foramen stenosis, and can provide accurate radiological evidence for sur-gery program.

Objective To evaluate the clinical efficacy and safety of hydrotalcite chewable tablets in treatment of patients with functional dyspepsia epigastric pain syndrome(EPS), and to investigate the onset time of hydrotalcite after the first dosage and whether use of hydrotalcite in EPS is a costeffective strategy. Methods A multicenter, randomized, open, positive controlled clinical trial was carried out in 240 patients with EPS. The subjects randomly received eigher hydrotalcite or omeprazole for 2 weeks. The improvemcnt and the disappear time of symptoms were evaluated before and after treatment and cost-effective was analyzed between two groups. Results It was demonstrated that both hydrotalcite and omeprazole could relief symptoms after treatment. After treatment for 2 weeks, the total effective rate was 85. 71% in hydrotalcite group and 90. 43% in omeprazole group with no significant difference (P＞0.05). The median onset time of hydrotalcite after first dosage was 0.417 h. The overall direct cost per patient was RMB ￥122. 29 for hydrotalcite treatment and RMB ￥242.95 for omeprazole treatment. The main adverse events included diarrhea, thirst, bloating,headache and belching. No severe adverse event was found in two groups. Conclusions Hydrotalcite has fast effect on relief of EPS symptoms. Use of hydrotalcite is a cost-effective strategy in the management of EPS. It is a safe and effective medicine in treatment of EPS.