Objective To survey the state of internet addiction of vocational college students and explore the effect of perceived social support and loneliness on Internet addiction.Methods In accordance with random cluster sampling,this research used the Revised Chen Internct Addition Scale,Perceived Social Support scale,and UCLA Loneliness Scale to study lnternet addiction among a total of 1 602 vocational college students from three higher vocational colleges in Guangzhou.Results [nternet addiction rate was 9.87％,and Internet dependence rate was 24.78％.Internet addiction had a higher incidence rate among male students than that among female students (x2=19.775,P＜0.01).The perceived social support group of vocational college students was low,which indicated serious loneliness based on the Loneliness Scale,and their scores on Internet addiction tendency were higher than those of other groups (P＜0.01).The total scores in Internet addiction tendency and perceived social support were negative (r=-0.183,P＜ 0.01),which indicates positive correlation with loneliness (r=0.243,P＜ 0.01).The mediating effect of perceived social support and Internet addiction on loneliness was significant,with a mediation rate of 69.63％.Conclusion Internet addiction tendency of vocational college students is a problem that deserves more attention.Low social support and loneliness can increase the incidence rate of internet addiction tendency.Loneliness is also found to be a strong predictor of internet addiction.

Objective To establish a rapid,accurate and sensitive method for the determination of toluene diisocyanate(TDI) in plastic playground.Methods The samples were distilled continuously for 12 hours by acetone at 80-85 ℃ in water bath,and after centrifuged,precipitated and filtered,separated by using GC1490,7% SE-30 column,the contents of TDI in the samples were determined by gas chromatography.The qualitative and quantitative analyses were carried out by the retention time and peak area respectively.Results The linear range of the method was 0.001 30-0.043 80 mmol/L.Regression equation was y=28 612x-29.336,with r=0.999,and the limit of detection was 0.001 30 mmol/L.The rates of recovery ranged 100.8%-103.6%,with RSD of 5.7%.Conclusion The developed method was rapid,accurate,sensitive and is applicable to the determination of TDI inplastic playground.

Objective To investigate the effect of tadpole extract(T871 3) on tumor cells and its mechanism. Methods We studied the effects of T871 3 on proliferation, differentiation and apoptosis of HL 60 cells by cytomorphological observation, cytochemistry and TUNEL method. We also examined gene expression during the induction of apoptosis and differentiation in tadpole extract treated HL 60 cells by in situ hybridization and intact cell mRNA dot blot techniques. Results 1 T871 3 was able to inhibite HL 60 cells proliferation. 2 T871 3 was able to induce HL 60 cells to differentiate along monocyte macrophage lineage at low concentration, and apoptosis at higher concentration. 3 The differentiation of HL 60 cells was accompanied by downregulations of c myc,c myb gene expression, The apoptosis of HL 60 cells was accompanied by downregulations of c\|myc bcl 2 gene expression, suggesting that these genes may be involved in the apoptosis and differentiation process. Conclusion Tadpole extract may have effects on HL 60 cells through changing the oncogene expression. [

Objective To evaluate the effects of remifentanil preconditioning on the renal injury induced by limb ischemia-reperfusion (I/R) in rats.Methods Twenty-seven healthy male Sprague-Dawley rats,weighing 200-250 g,were randomly assigned into 3 groups (n =9 each):sham operation group (Sham group),I/R group and remifentanil preconditioning group (RPC group).Limb ischemia was induced by clamping bilateral femoral arteries and veins for 2 h,followed by 24 h reperfusion in I/R and RPC groups.Remifentanil 1.0 μg· kg-1 · min-1 was infused via the caudal vein for 30 min before ischemia in RPC group,while the equal volume of normal saline was given in Sham and I/R groups.Blood sample was taken from the inferior vena cava at 24 h of reperfusion to measure blood urea nitrogen (BUN) and creatinine (Cr) concentrations in serum.The rats were sacrificed and the left kidney was removed for determination of tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) contents,cell apoptosis and microscopic examination of pathological changes.Apoptosis index was calculated.Results Apoptosis index and concentrations of BUN and Cr in serum,TNF-α and IL-6 contents,and apoptosis index were significantly higher,and the pathological changes were more severe in I/R and RPC groups than in Sham group.Compared with group I/R,concentrations of BUN and Cr in serum,TNF-α and IL-6 contents,and apoptosis index were significantly decreased,and the pathological changes were attenuated in RPC group.Conclusion Remifentanil preconditioning can attenuate renal injury induced by limb I/R in rats,and inhibition of inflammatory responses and cell apoptosis in kidney may be involved in the mechanism.

Objective To investigate the clinical significance of CD55,CD59 and Aeromonas hydrophila toxin variant (FLAER) in the diagnosis of anemia and paroxysmal nocturnal hemoglobinuria (PNH).Methods Collected 30 healthy controls,22 cases of PNH,33 cases of aplastic anemia (AA),37 cases of iron deficiency anemia (IDA),45 cases of megaloblastic anemia (MA),30 cases of hemolytic anemia (HA) and 31 cases of myelodysplastic syndrome (MDS) from January 2009 to March 2017,CD55,CD59 and FLAER negative cell ratio of peripheral blood neutrophil of them were detected by multipa rameter flow cytometry.Results The detection rates of FLAER in PNH,AA and MDS groups were higher than those of CD55 and CD59,but there was significant difference in AA (x2 =7.759,5.518,P=0.005,0.019＜0.05).The average CD55,CD59 and FLAER deletion rate in PNH and AA group were significantly higher than those in normal control group and other groups (t=2.163～17.890,P=0.000～0.038＜0.05).The number of FLAER in PNH group was higher than CD59 and CD59 was higher than CD55 with the statistically significant difference (t=2.503 ～ 6.308,P=0.000 ～0.016＜ 0.05).Conclusion CD55,CD59 and FLAER have important value in the diagnosis of PNH and differential diagnosis with other anemia diseases,and can also be used to detect the presence of MDS and AA in patients with PNH.FLAER outperforms CD59,CD59 outperforms CD55.

Objective To examine the reliability and validity of Chinese version of the achievement goal questionnaire(AGQ).Methods The English version of the AGQ was translated into Chinese which was then translated into English again to verify that the Chinese version was the same constructs as the original version.Stratified chester sampling method was used for 1115 university students.Additionally,internal consistency,test-retest and confirmatory factor analyses were analyzed.Results (1) All of the NFI (0.941),CFI (0.953),TLI (0.924),x2/df (2.386),REMEA (0.046) met the criteria standards for adequacy of fit.The factors loadings ranged from 0.47 to 0.93 ; the squared multiple correlations were 0.22-0.86.(2) The invariance of the AGQ across gender was supported.(3)The Cronbach's α coefficient of the AGQ was 0.83;the test-reliability coefficient was 0.77 ;the mean interitem correlation coefficients ranged from 0.40 to 0.57.(4) The correlation coefficients of the four factors with the total scale score ranged from 0.54 to 0.77,and the correlation coefficients among the four factors ranged from 0.06 to 0.61.Performance approach and master approach goal was significantly positive correlations with self-esteem.Performance avoidance and mastery avoidance goal was significantly negative correlations with self-esteem,but positively with anxiety.Master approach goal was significantly negative correlations with anxiety.Conclusion The Chinese version of the AGQ is a reliable and valid method for assessing achievement goal in Chinese-speaking sample.

Objective To screen out the individuals at high cognitive risk by using the weakest link theory,and explore the characters of the cognitive emotion regulation.Methods 600 undergraduate students were tested with cognitive style questionnaire,general social and academic hassles scale,center for epidemiologic studies depression scale,and cognitive emotion regulation questionnaire.Results There were significant differences between individuals of high and low cognitive risk in self-blame (13.32 ± 2.12) vs (12.45 ± 2.27),rumination,catastrophizing,blaming others,positive refocusing and positive reappraising.Catastrophizing,generality,rumination,positive reappraising,stress,self-blame,and self could predict 34.2％ of depression.Conclusion There are differences between individuals of high and low cognitive risk in cognitive emotion regulation.Catastrophizing,generality,rumination,positive reappraising,stress,self-blame,and self are the main predictors of depression.

Objective To establish a luciferase labeled McA-RH7777 hepatoma rat model,which could be used for gross observation to further observe the effect of selective ligation of the portal vein and bile duct on tumor growth and metastasis.Methods The luciferase gene was transfected into rat McA-RH7777 hepatoma cells with pCDH-puromycin-CMV as the carrier,which were subcutaneously inoculated into Buffalo rats.Tumor pieces were then heterotransplanted into the left lateral lobe of the allogenic rat liver to observe the tumor growth in vivo.After the successful hepatoma modeling,the rats were randomly divided into three groups,namely the implanted portal vein group with combined portal vein and bile duct ligation,the implanted portal vein group with single portal vein ligation and sham operation group.The rats were executed at the 1 st week and 2nd week after ligation,and the livers were dissected to record the tumor growth and metastasis inside and outside the liver,respectively.Results The tumor formation rates of Buffalo rats after subcutaneous and intrahepatic implantation were both 100％.The fluorescence signal implanted into the liver lobe could be observed in vivo after the intrahepatic implantation of luciferase transfected Luc-McA-RH7777 at 2nd week,the range and intensity of which increased over time.Only local tumor growth could be found at the 4th week,without obvious intrahepatic and lung metastasis.However,both an increased in situ tumor volume and the pulmonary metastasis could be observed in the implanted portal vein group with combined portal vein and bile duct ligation at 2nd week after the ligation.Immunohistochemistry showed AFP positive immunoreactions in the vast majority of intrahepatic tumor cells and Luc positive immunoreactions in part of tumor cells.Conclusion Luc-McA-RH7777 cells could be used to establish the heptoma rat model and the in vivo analysis within the Buffalo rat liver demonstrated that the combined ligation of the portal vein and bile duct can accelerate the development and metastasis of liver cancer.

Four crystalline forms of clopidogrel bisulfate were characterized by analytical techniques. Aiming to research the absorption characteristics of clopidogrel bisulfate polymorphs after taken orally by rat, and to estimate the influence of crystal form to pharmacodynamic action, four crystalline forms of clopidogrel bisulfate were administered intragastrically to rats, and high performance liquid chromatography (HPLC) was used to measure the contents of clopidogrel bisulfate and its metabolite in rat plasma. The metabolite of clopidogrel bisulfate was detected in rat plasma. There were significant deviations among four crystalline forms in the areas under curve of the metabolite of clopidogrel bisulfate. We concluded that the different crystal forms of clopidogrel bisulfate showed different pharmacokinetic characteristics, which might affect pharmacodynamic action.

One hundred and thirty seven pafients diagnosed by coronary angiography were recruited in the study and divided into coronary heart disease group(CAD)and control group.Relationship between serum apolipoprotein M levels and the severity of stenosis of coronary arteries was analyzed.In covariate analysis,serum apolipoprotein M levels were significantly lower in CAD group than those in control group adjusted for sex,age,body mass index(BMI)(P＜0.05).By stepwise muhiple regression,serum levels of apolipoprotein M were correlated positively with BMI(r=0.65,P＜0.01),and correlated negatively with total cholesterol(TC)(r=-0.53,P＜0.01)and low density lipoproteins(LDL-C)(r=-0.42,P＜0.01).Serum levels of apolipoprotein M were correlated negatively with the score of coronary stenosis(r=-0.62,P＜0.01).The results suggest that apolipoprotein M might be related to the development of coronary artery disease.