Users' cognition and information retrieval are faced with great challenges in ubiquitous knowledge environ-ment. The influence of cognitive factors such as personality traits, cognitive style and ability, knowledge structure and ascribed methods on users' information retrieval behaviors was thus analyzed. It was pointed out that different cognitive factors could influence the retrieval, judgment and absorption of its results,users' satisfaction and continuous use in ubiquitous knowledge environment,with suggestions put forward from the aspects of information retrieval education, information service and information users for improving the users ' knowledge system in knowledge assimilating process by working out effective retrieval strategies using the advantages of cognition.

Objective: To explore the effect of low-level laser irradiation (LLLI) preconditioning on milieu of infarcted myocardium in experimental rats.
Methods: The myocardial infarction (MI) model was established by left anterior descending (LAD) artery ligation in female rats. 3 weeks later, the qualified MI rats were randomly divided for 3 groups: ① LLLI preconditioning group, the rats received thoracotomy for LLLI by a 635nm, 5mW diode laser with the energy density of 0.96 J/cm2 for 150 seconds, n=26. ② Control group, the rats received thoracotomy for daylight irradiation, n=27. ③ Sham operation group, the rats received thoracotomy without LAD ligation, n=24. The Expressions of myocardial vascular endothelial growth factor (VEGF), glucose-regulated protein 78 (GRP78), superoxide dismutase (SOD) and malondialdehyde (MDA) were evaluate by real time-PCR, Western blot analysis and other relevant laboratory test at 1 hour, 1 day and 1 week after treatment. The myocardial cell apoptosis was examined by TUNEL staining, and left ventricular function was detected by echocardiography.
Results: LLLI preconditioning obviously increased the myocardial VEGF, GRP78 expression and SOD activity, decreased MDA production; while it could not really improve the myocardial cell apoptosis at peri-infarcted area and left ventricular function in experimental rats.
Conclusion: LLLI preconditioning may improve the milieu of infarcted myocardium via decreasing the oxidative stress in experimental rats.

BACKGROUND: With the prevalence of total knee arthroplasty, periprosthetic joint infection as a serious complication has been an issue of concern.OBJECTIVE: To summarize the advances in the diagnosis and treatment of infection after total knee arthroplasty.METHODS: The first author searched the PubMed and CNKI databases for the literatures related to the diagnosis and treatment of infection after total knee arthroplasty using the keywords of total knee arthroplasty,infection in English and Chinese, respectively. The repetitive articles were excluded, and the risk factors,diagnosis, classification and treatment of infection after total knee arthroplasty were summarized.RESULTS AND CONCLUSION: (1) The infection after artificial knee replacement is closely related to the patient's preoperative condition, operation skills and postoperative status. (2) Diagnosis of infection is based on the detailed understanding of the patients' situation and complete auxiliary examinations. (3) The treatment methods include antibiotics, debridement and retention, reversion, arthrodesis, as well as amputation. (4) Periprosthetic infection is a serious complication after total knee arthroplasty, and early diagnosis and treatment are critical. Furthermore,choosing an appropriate individualized treatment scheme for different patients is important.

Objective To build a bio-material artificial chest wall and discuss its feasibility and efficiency in reconstruction of huge bony defects of chest wall in mongrels in comparison with traditional "sandwich" procedure. Methods (1) The procine osteal and membranate tissues were treated with epoxy cross linking method and their surfaces were modified with amino acid solutions at various concen-trations and at different temperatures to obtain an artificial pleura and artificial ribs for construction of the artificial chest wall. (2) The huge bony defects (5 cm×5 cm) were created in chest wall of five Chinese mongrels. (3) Three mongrels in test group was repaired with artificial chest wall, while two mongrels in control group was repaired with traditional "sandwich" complex. A follow-up was carried out to observe reconstruction effect and rejection in both groups at 3,6 and 12 months after implantation. Results There was no death found during the perioperative period and at 12 month follow-up in test group, with abnormal contour of chest wall and good thoracic activity after reconstruction. In the meantime, there found no rejection, collapse in the repaired region or paradoxical respiration. The postoperative X-rays at 3,6,12 and 24 months showed a good integrity of the thorax, with no collapse, deformation or abnormal movement. Meanwhile, the follow-up of control group showed a normal contour but slight collapse, with no paradoxical respiration. The Chest X-ray examination revealed that the bone cement in" sandwich" complex was X ray opaque and showed mild abnormal movement with breathing. The common blood test and immune items showed no abnormal. Conclusions The bio-material artificial chest wall is a safe and effective reconstruction technique for bony defects of thoracic wall in mongrels, with no acute or chronic rejection.

Aim Toexploretheinhibitioneffectof triptolide on nasopharynx cancer, and the mechanism. Methods Theinhibitionofcellproliferationwasde-tected by MTT assay;the cell apoptosis was analyzed by flow cytometry with propidium iodide staining. The ex-pressions of glucose regulated protein 78 ( GRP-78 ) , Akt and pAkt in cells were examined by Western blot;the effect of triptolide on reactive oxygen species ( ROS) accumulation was detected by ROS Fluorescent Probe-DHE.Results MTTassayshowedthatthe growth of nasopharynx cancer was inhibited by triptol-ide , and the inhibition occurred in a dose and time-de-pendent manner following triptolide treatment in CNE-2Z nasopharynx cancer cells. Propidium iodide staining revealed that the apoptosis of CNE-2 Z cells was in-duced remarkably by triptolide. After CNE-2Z cells treated with 25, 50,100 nmol·L-1 of triptolide for 24 h, the apoptosis rate was 14%,26. 9% and 34. 4% re-spectively. Western blot experiment showed that the expression of GRP-78 had no significant change follow-ing triptolide treatment in CNE-2 Z nasopharynx cancer cells for 24 h, but the expression and the phosphoryla-tion level of Akt were strikingly decreased. The experi-ment of ROS uncovered that CNE-2 Z nasopharynx cancer cells increased generation of ROS after treat-ment with triptolide for 4 hours, and acted cells in a dosedependentmanner.Conclusions Triptolidecan inhibit the growth of CNE-2 Z nasopharynx cancer cells in a dose and time-dependent maner. The mechanism may be related with the point that triptolide can induce oxidative stress, incease ROS, inhibit the expression and the phosphorylation level of Akt,then promote the apoptosis of CNE-2Z cells.

The paper introduces a designing idea and a carrying-out scheme about expanding functions of single channel electrocardiograph in Chinese community medical service and looks forward to its applying prospects.
Community Health Services ; Electricity ; Electrocardiography, Ambulatory ; instrumentation ; Equipment Design ; Humans ; Microcomputers ; Signal Processing, Computer-Assisted ; Software

Objective Aprotinin has been suspended in cardiac surgery since risks factors associated with mortality and other adverse events in western Literatures.This study was to investigate the effect of aprotinin on short-term outcomes in cardiac surgery in Chinese patients.Methods Two groups of patients who underwent cardiac surgery during equal period just before and after aprotinin was suspended in China.Aprotinin groupp(n=1699) was defined as operations from june 19,2007 to Dec 18,2007,when aprotinin was used in all the patients.Control group(n=2225)was defined as operations from Dec19,2007 to June 18,2008,when aprotinin was not umed.Postoperative outcomes between the two groups,including blood loes and transfusion requirement,in-hospital mortality and major adveme outcome events were compared,using univariate analysis and mulfivariable logistic regression analysis.Results Aprotinin group had less postoperative blood loes,transfusion requirement and reoperation for bleeching as compared with the control group.Application of aprotinin did not increase the risk of in-hospital mortality (0.5%vs.10%,P=0.08)and other major ad-verse events,including renal dysfunction,renal failure requiring dialysis,low cardiac output syndrome (LCOS),neurological and pulmonary complications.Aprltinin group also had and shorter mechanical ventilation time(P=0.04),a lowwer rate of delayed mechan-ical ventilation time(P=0.04)and a higher PaO2/FiO2 in the bolld gas analysis(P<0.001).which presented a better respiratory function.Multivariable Logistic regression analysis got identical results with univariate analysis.Conclusion The use of aprotinin in cardiac surgery could reduce blood loss and transfusion requirement significantly,and showed a protective effect on the lungs.In the mean time it did not increase the risk of mortality or major complications.We suggest further studies should be performed to make a decision of continuing or stopping the use of aprotinin in cardisc surgery in Chinese or Asian population.

Objective To analyze the distribution and pulsed-field gel electrophoresis (PFGE)of pathogenic bacteria causing infectious diarrhea in a district of Beijing from 2011 to 2013,and provide basis for tracing infection sources.Methods A total of 1 179 stool specimens of infectious diarrhea from patients in a diarrhea outpatient department from January 2011 to December 2013 were collected,all isolated pathogens were identified by serotyping and PFGE analysis.Results 330 enteric pathogens were isolated from 1 179 specimens,the top 4 bacteria were Shi-gella spp .(28.18%,n=93),Salmonella spp .(20.91 %,n=69),Vibrio parahaemolyticus (13.33%,n =44),and diarrheagenic Escherichia coli (3.33%,n = 11 ).18 Shigella sonnei isolates were identified as 8 PFGE patterns, clustering similarity was close to 88%;69 Salmonella spp .strains belonged to 18 serotypes and 41 PFGE patterns, Salmonella senftenberg and Salmonella enteritidis had dominant patterns;no dominant PFGE patterns were obviously identified among 23 strains ofVibrio parahaemolyticus .Conclusion The serotypes and PFGE patterns of pathogenic bacteria in infectious diarrhea in past three years showed a wide distribution characteristics,the dominant PFGE patterns of Salmonella spp .and Shigella spp .need to be paid more attention,and outbreak of infectious diarrhea caused by Salmonella spp .and Shigella spp .should be alerted.

Objective To assess the safety and efficacy of an olive oil-based lipid emulsion for parenteral nutrition in patients after esophagectomy.Methods In the randomized controlled trial,60 patients undergoing esophagectomy were divided into study group(n=30,received olive oil-based lipid emulsion)and control group [n=30,received medium-chain triglyceride/long-chain triglyceride(MCT/LCT)emulsion].The parenteral nutrition Was provided for 7-10 postoperative days.The nutritional formulas were equivalent in nitrogen,calorie,osmotic pressure,and fluid volume.Peripheral venous blood tests were performed before operation and on the first and eighth postoperative days.All the patients were evaluated by nutritional status(weight,body mass index,nutritional risk screening,etc.),safety profiles[full blood test,electrolytes,aspartate aminotransferase(AST),alanine amiotransferase(ALT),total bilirubin and direct bilirubin,blood urea nitrogen(BUN),creatinine,blood glucose,etc.],and efficacy indicators(hemoglobin,albumin,total protein,etc.).Results The albumin and total protein levels returned to the normal ranges in beth groups 8 days after operation,although both levels were significantly higher in study group(P=0.000).Also,the difference of total protein levels between the eighth and first postoperative days Was significantly higher in the study group(P=0.002).In addition,the AST and BUN readings returned to normal ranges 8 days after operation in the study group, which were significantly lower than those in control group (P = 0.025, P = 0.013).No serious adverse events were reported in both groups.Other nutritional parameters, renal and hepatic safety profiels, vital signs, and hematology showed no significant difference between two groups.Conclusions Olive oil-based lipid emulsion is a safe and efficient lipid emulsion for parenteral nutrition in patients undergoing esophagectomy.Compared with MCT/LCT, it has less effect on AST and BUN.

Aim To investigate the effects of irbesartan on Wnt/β-catenin signaling pathway in tubular epithelial-mesenchymal transition(EMT)in HKCs induced by high-glucose.Methods Human kidney proximal tubular epithelial cell line(HKCs)cultured in vitro was divided into four groups:normal-glucose group,mannitol control group,high-glucose group and high-glucose plus irbesartan group.Immunocytochemistry staining was used to observe the expression of β-catenin;the protein expression of Wnt4,β-catenin,E-cadherin and α-SMA was assessed by Western blot;Wnt4 and β-catenin mRNA were detected by reverse transcription-polymerase chain reaction(RT-PCR).Results Compared with normal-glucose and mannitol control group,both the protein and the mRNA of Wnt4 were up-regulated in HKCs stimulated by high-glucose.α-SMA expression significantly increased but E-cadherin decreased in HG group.The cytoplastic and nuclear fraction of β-catenin enhanced with highglucose stimulation.But no difference of the total protein and mRNA of β-catenin was observed between highglucose-treatment and control groups.Highglucose induced Wnt4 and β-catenin expression in a time-dependent manner,both peaking at 24 h.Irbesartan reduced the promotional effect of HG on Wnt4 and α-SMA expression,and nuclear translocation of β-catenin.HG-mediated inhibition of E-cadherin was also restored by irbesartan.Conclusion These data supported a functional role for Wnt/β-catenin signaling pathway during epithelial-mesenchymal transition of HKCs induced by high glucose and suggested that irbesartan might reverse tubular EMT by regulating activity of Wnt/β-catenin pathway.