0.99).The IL-2 activity of control sample of our laboratory was determined according to recom-binant human IL-2 standard,the ability of IL-2 induced by rat and mouse spleen cells was compared, and the parameters of IL-2 induced by rat spleen cells were detected.The partially purified rat IL-2 was obtained through ammonium sulfate precipitation, gel filtration and chromatography.

Internet Addiction has become an International problem,especially in China.At the present time,such researches are mainly written in psychological area.Opinions in these researches vary,even conflict with one another.Therefore,only grasping the basic features of the college students' Internet Addiction,can we prevent the college students from Internet Addiction and intervene in it with a clear aim.

Mechanism studies in the gene regulation in the eukaryotic cells is one of the momentous areas in molecular biology.Regulation at transcription level is a complex progress with multiple steps with the presence of the gene functions.There exist ubiquitous occurrence of transcription factors in mammalian tissues and biodiversity in the factors.These transcription factors are found to relate closely to various carcinogeneses,including cell proliferation,apoptosis,invasion and angiogenesis.Understanding of transcription factors and their action mechanisms,through the activation and inhibition of transcription factors,would potentially lead to the discovery of new entities in the targeting treatment and prevention of the cancer diseases.

Objective To investigate the clinical value of penetrating-suture type pancreaticojejunostomy (PPJ) after pancreaticoduodenectomy (PD).Methods The clinical data of 77 patients who received pancreaticoduodenectomy from Taixing People's Hospital from June 2002 to March 2012 were retrospectively analyzed.Of all the patients,34 received PPJ after PD (PPJ group),and the other 43 patients received PJ anastomosis (control group) based on the texture and size of the pancreas,pancreatic duct diameter (duct-to-mucosa pancreaticojejunostomy for pancreatic duct diameter ≥ 4 mm,end-to-end or binding pancreaticojejunostomy for pancreatic duct diameter ≤3 mm).Pancreatic fistula was diagnosed according to the criteria of the International Study Group on Pancreatic Fistula,including grade B or C pancreatic fistula with clinical value.Patients were followed-up through outpatient examination and telephone interview till May 2012.Data were presented by x ± s or median (range) and the t-test and Wilcoxon rank-sum test were used to evaluate quantitative data with or without normal distribution,respectively.Qualitative data were analyzed using Pearson x2 test or Fisher's exact test.Results The mean diameter of the pancreatic duct was 3 mm for both the PPJ group and the control group.The external drainage via the pancreatic duct stent was not used in the PPJ group,compared with 4 cases in the control group,showing a statistically significant difference between the 2 groups (x2=3.632,P ＜ 0.05).The duration of pancreaticojejunostomy was 12 minutes (range,8-25 minutes) in the PPJ group,while no records in the control group.The operation time and intraoperative blood loss in the PPJ group and the control group were (304 ± 60)minutes and (475 ± 75) mL,(304 ± 60) minutes and (500 ± 97) mL,respectively.Twenty-four (70.6％) patients in the PPJ group and 29 (67.4％) patients in the control group received intraoperative blood transfusion,with volume of 400 mL (range,300-800 mL) and 600 mL (range,300-1 200 mL),respectively.The median duration of postoperative hospital stay were 18 days (range,11-32 days) in the PPJ group and 20 days (range,9-44 days) in the control group.None of these comparisons were statistically significant between the 2 groups (t =1.293,0.619,x2=0.088,Z =0.165,0.074,P ＞0.05).The rate of grade B or C pancreatic fistula were 0 for the PPJ group and 27.9％ (12/43) for the control group,and the mortality rate of patients who had pancreatic fistula were 0 and 11.6％ (5/43) for the PPJ group and the control group,with statistical significance (x2=11.232,4.237,P ＜0.05).The overall incidence of bile leakage,peritoneal bleeding and delayed gastric emptying in the PPJ group and the control group were 5.9％ (2/34),2.9％ (1/34),5.9％ (2/34) and 11.6％ (5/43),7.0％ (3/43),14.0％ (6/43),with no significance difference (P ＞0.05).Fifty-six patients were followed up after operation from 9 months to 5 years.Pancreatic duct dilation was detected by imaging examination for 26 patients in the control group.Conclusions PPJ is a simple and feasible approach with better clinical efficacy after PD.

A new method for determining transaminase activity based on the color change of the reaction solution was established, by using alanine-dependent transaminase VfTA from Vibrio fluvialis JS17 as the research object coupled with pyruvate oxidase and horseradish peroxidase. After the optimization of the conditions, the linear relationship between VfTA activity units and the absorbance at 400 nm was investigated. This method was also applied to determine the activity of commercial transaminase ATA117. The results showed that the detection limit of transaminase VfTA activity was up to 0. 45 U/mL and the detection limit of ATA117 activity was up to 0. 5 U/mL. The transaminase activity could be quickly judged according to the color depth of the reaction solution.

Diketoreductase can catalyze a double reduction of β,δ-diketo ester to corresponding dihydroxv product with enantiomeric excess(ee)and diastereomeric excess(de)both greater than 99.5%.In order to explore the catalytic mechanism of this unique enzyme,the present study investigated the diketone reduction process and reaction characteristics by diketoreductase.We found that two mono-hydroxy intermediates were produced during the diketone reduction and its reverse reaction.The two intermediates were further separated by C18 column chromatography and structurally confirmed by chiral HPLC with authentic standards.Two mono-hydroxy intermediates could be served as the substrates for the reduction by diketoreductase with different reaction velocities.The formation and disappearance of intermediates were largely affected by temperature and substrate concentration.In addition,steady state kinetics with the two intermediates showed different reaction rates in their disappearance.Collectively,the results indicate that the diketone reduction undergoes a two-step process with the formation of both intermediates,but the disappearance rates for the two intermediates are slightly different.

The gut-brain axis (GBA) is a nerve-endocrine mediated bidirectional communication system between the gut and brain, which links the cognition and emotion in brain to peripheral intestinal function. In recent years, many researches have showed that colonized intestinal microbiota plays an important role in the communication between gut and brain. On one hand, microbiota can influence the development and function of brain via GBA. On the other hand, brain can also change the composition of gut microbiota. These findings gradually become a novel medical research highlight, i.e. the microbiota-gut-brain axis. This paper reviews the interaction between gut microbiota and brain via GBA in order to provide supports for studying functions of gastrointestinal tract and brain, as well as the treatment of related diseases.

Objective To study the adsorption and separation of licorice flavonoid with macroporous resins. Methods Eight types of macroporous resin were selected to compare their performances in absorbing and desorbing licorice flavonoid. The optimal type for licorice flavonoid was decided, meanwhile, its kinetic curve and dynamic absorbing behavior were studied. Results HPD300 resin possessed higher adsorption and desorption capacity. The appropriate adsorption and desorption conditions were as follows:concentration of sample was 2.0 mg/mL, velocity of sample solution was 1.5 BV/h, volume of sample solution was 2 BV (bed volume);velocity of 80%ethanol was taken as eluant 1.5 BV/h, and the volume was 3 BV. Flavonoid content was increased more than 2 times under above conditions. Conclusion HPD300 macroporous resin showed better comprehensive adsorption property. It can be used to purify and separate licorice flavonoid.

Objective To investigate the adverse reactions by stereotactic body radiation therapy(SBRT)for advanced hepatocellular carcinoma and summarize nursing experience.Methods Forty-one patients with advanced hepatocellular carcinoma from the radiation department of Sun Yat-sen University Cancer Center from July 2010 to May 2012 were enrolled in this retrospective study.The adverse reactions were closely observed and the patients were given pertinent nursing.Results The effectiveness rate was 56.2%.During the therapy,36 patients developed nausea/vomiting of grade 1-2,taking up 87.8%,18 had grade 1-3 elevation of liver enzymes,taking up 43.9%,16 had grade 1-2 decrease of white blood cells,taking up 39.0%,8 had grade 1 anemia,taking up 19.5%and 21 had grade 1-2 decrease of blood platelet,taking up 51.2%.The adverse reactions were contained satisfactorily through careful observations and pertinent nursing.Conclusions The toxic reactions by SBRT are nausea,vomiting,enzymes elevation and decrease of whole blood cell.Therefore,nurses need to observe these toxic reactions carefully and give pertinent care to the patients so as to prevent the complications,especially radiation-induced liver injury.

ObjectiveTo determine the current students' social anxiety status and maternal factors in school students( grade 5-7) in Harbin,and provided scientific guidance relevant to students'social anxiety.Methods 1526 mother-child pairs collected by random cluster sampling,children completed the social anxiety scale for children (SASC),security scale,coping strategies questionnaire( consist of ambivalence and avoidance subscale),acceptance scale and psychological control scale,and mothers completed the center for epidemiologic studies depression inventory (CES-D),self-rating anxiety scale (SAS).ResultsThe total positive detection rate of social anxiety was 13.6％,there was no significantly difference between boys and girls (P ＞ 0.05) ; the positive detection rate of Grade 6 was higher than Grade 5 and Grade 7.There were positive correlation between social anxiety and mother's psychological control,mother's depression,mother's anxiety ( r =0.228,0.143,0.122) ; negative correlation with mother's acceptance( r =-0.214).Linear regression indicated that only three variables (mother's psychological control,mother's acceptance,mother's depression) were at the P ＜ 0.05 level.The regression coefficients for the three variables were 1.557,- 1.092 and 0.040,respectively.ConclusionMaternal highly psychological control,lowly acceptance and maternal anxiety depression all play a role in promoting the occurrence of students' social anxiety.