BACKGROUND: Human embryonic stem cells (hESCs) are pluripotent cells which may differentiate into tissues of all three germ layers. Such research as the feeder-free growth of hESCs is few in China. Fibroblast growth factor (FGF) is a major factor to maintain the undifferentiated state of hESCs.OBJECTIVE: To evaluate the ability of FGF at different concentrations in maintaining the undifferentiated state and pluripotency of hESC lines in the long-term culture.METHODS: Two cell lines of hES-8 and hES-18 were cultured with mouse embryonic fibroblast condition medium for 3 passages and then transferred into mouse embryonic fibroblast condition medium containing different concentrations of FGF: 100, 160, 250 μg/L for 8 passages. The hESCs were removed from the petri dish, cell clusters were digested with collagenase IV and gathered. Cell differentiation and pluripotency were observed. The eighth generation of the hESCs were collected and incubated into severe combined immunodeficiency mice, so as to observe teratoma formation. Morphologies of the cells were evaluated. Alkaline phosphatase staining, surface labeling immunocytochemical analysis and RT-PCR assay method were utilized to determine the OCT-4 expression and tumorigenesis in vivo.RESULTS AND CONCLUSION: Cultured in mouse embryonic fibroblast condition medium containing 160 and 250 μg/L FGF, two cell lines of hESC could maintain undifferentiated state: Clones were round with a high ratio of nucleus to cytoplasm. Large areas in the center of clones were undifferentiated cells, while surrounding the clones were differentiated cells; Strong positive expression for alkaline phosphatase staining was observed; Two cell lines showed high levels of OCT-4 transcription factor protein; The surface markers SSEA-4, TRA-1-60, TRA-1-81 were all positive on both two lines; The hESC clusters could form embryoid body in vivo 10 days later; 3 germ layers of teratomas were also obtained after implanted into severe combined immunodeficiency mice. Mouse embryonic fibroblast condition medium containing 100 μg/L FGF was not sufficient to maintain the long-term proliferation of hESCs, and most of the cells differentiated and died after 4 passages. Alone with concentration 160 μg/LbFGF or more could maintain two hESC lines undifferentiated stably in vitro, has no influence on the differentiation and totipotency of two cell lines.

Based on a review of literature and the current reform of public hospital corporate governance,such corporate governance is divided intocombined regulation and operation,anddivided regulation and operationmodels.Then the principal-agent theory was called into play to analyze the main problems and causes of the existing models.From the perspectives of government supervision and assessment,professionalization of hospital directors,market competition mechanism,thoughts were made on how to improve such corporate governance.

Objective:To study the chemical constituents in the seed of Cassia leschenaultiana.Methods: The compounds were separated and purified by column chromatography , thin-layer chromatography and recrystallization .The structures were identified by the physicoche mical identification and spectral analysis .Results:Seven compounds were isolated from the seeds of Cassia leschenaultiana and identified as 1-desmethylchryso-obtusin (Ⅰ) , aurantio-obtusin (Ⅱ) , ale-emodin (Ⅲ) , obtusin (Ⅳ) , chryso-obtusin (Ⅴ) , ob-tusifoline(Ⅵ)and aurantio-obtusin(Ⅶ).Conclusion:All of the compounds are isolated from the seeds of Cassia leschenaultiana for the first time.

Constant infusion, exponentially declining infusion and program infusion of theophlline were administered to rabbits byadopting the rabbit population pharmacokinetic parameters in this laboratory, and the plasma concentrations of the drug was measured by ul- traviolet spectrophotometry. The results showed that the plasma drug concentrations following exponentially declining infusion and program infusion attained the desired steady-state level at only 30 min, though the T1/2?= 6. 08h, The median absolute value of performance error in pro-gram infusion and exponentially declining infusion was 7. 8% and 14% respectively.

Objective:To study effects of psychological intervention and sedativn on stress response to gastroscopy.Methods:86 patients for gastroscopy were randomly divided into three groups:29 patients in group of psychological intervention watched video materials about psychological intervention before gastroscopy;29 patients in sedative group were given intravenous midazolam and propofol.; 28 patients in control group were no psychological intervention or sedation. Patient's discomfort and changes of blood pressure(BP),heart rate(HR) , saturation of pulse oxygen(SpO 2) were recorded. The level of norepinephrine(NE), adnephrin(E), dopamine(DA) and cortisol(CS)in serum were detected.Results:The incidence of cough,nausea and vomiting, and restlessness in group of psychological intervention and in sedative group was lower as compared with the control group. BP,HR,NE,E and CS in control group rose significantly during the procedure while that of patients in group of psychological intervention and in sedative group was no significant change.Conclusion:The psychological intervention or sedation with midazolam and propofol can reduce stress response to gastroscopy.

Objective To explore the effects of inflammatory mediator blocker AG490 on neurological deficits,apoptosis and expression of caspase-3 following cerebral ischemia-reperfusion(I/R) in rats.Methods The male SD rats were randomly divided into the groups sham-operation,I/R,saline and AG490;and the focal cerebral I/R models were made by middle cerebral artery thread embolism method.AG490(1 mg/kg) was intraperitoneal injection in AG490 group immediate and 12 h after ischemia-reperfusion respectively.The neurological deficits score was evaluated in 24 h after I/R in each group.The number of apoptosis in cerebral tissue was examined by d-utp nick end labeling staining(TUNEL).The expression of P-JAK2,P-STAT3,caspase-3 were detected by Western Blot.Results Compared with the groups I/R and saline,the neurological deficits score in AG490 group was significantly decreased(all P

Objective To study the transfer of ropivacaine across the single cotyledon of the term human placenta and the effects of maternal hypoproteinemia and fetal acidemia on the transfer. Methods Eighteen placentas were obtained from healthy full term parturients within 5 min after vaginal or cesarean section delivery. The dual perfused human placental model was made. The placentas were randomly divided into three groups of 6 placentas : (A) control group in which 100% fresh frozen plasma was used in both maternal and fetal circulation with pH maintained at 7.4 on both sides; (B) fetal academia group in which 100% fresh frozen plasma was used in both circulations but fetal pH was reduced to 7.0; (C) maternal hypoproteinemia group in which 50% fresh frozen plasma used in maternal circulation and 100% fresh frozen plasma in fetal circulation, pH was maintained at 7.4 on both sides. Samples were taken from the perfusate in the reservoir at 15, 30, 60, 90, 120 min after ropivacaine (2?g?ml-1) and antipyrine (10 ?g?ml-1 ) were added in maternal circulation for determination of concentrations of ropivacaine, antipyrine, glucose and lactate. Glucose consumption rate, lactate generation rate and relative and absolute transfer ratio of ropivacaine were calculated. Results Absolute transfer ratio of ropivacaine was gradually increasing with perfusion time, reaching 8.7?1.0% (A) , 10.5 ?1.6% (B) and 11.8?1.1% respectively at 120 min. Relative transfer ratio of ropivacaine was relatively constant during 120 min perfusion and was significantly higher at each time point in group B and C than in group A ( P

Objective:To establish the HPLC fingerprint of Cassia leschenaultiana from different regions. Methods: The column was SinoChrom ODS-BP (250 mm × 4. 6 mm, 5 μm). The mobile phase consisted of acetonitrile-0. 1% phosphoric acid with gradient elution. The flow rate was 1. 0 ml·min-1 , the detection wavelength was 285 nm, the column temperature was 25℃, and the injection volume was 10 μl. Results: The fingerprint consisted of 13 common peaks. The range of similarity for ten batches of Cassia le-schenaultiana was 0. 839-0. 998. And the reference fingerprint of Cassia leschenaultiana was established by HPLC. Conclusion: The fingerprint method is simple and reproducible, which can provide basis for the quality control and the medicinal resources exploration.

Phospholipase A_2 (PLA_2) inhibitor quinacrine was used to explore protective effect on multiple organ dysfunction (MOD) caused by intestinal ischemia-reperfusion (I/R) in rats. Gut I/R caused the increase of gut PLA_2 activity and induced endotoxemia and bacteriemia. Pretreatment with intravenous quinacrine 10mg?kg~(-1) attenuated bacteria and endotoxin translocation,markedly lowered the levels of thromboxane A_2 and prostacyclin I_2 in blood,and provided protection from the development of vital organs dysfunction. As a result,the survival rate in pretreatment group increased by 25%. The results demonstrate that gut I/R promotes gut barrier failure,then contributes to the development of MOD by allowing bacteria or endotoxin reaching the circulation. PLA_2 and PLA_2-dependent lipid mediators play an important role in the development of gut I/R injury and MOD. Intravenous quinacrine has protection against MOD resulting from gut I/R.

Objective: We investigated experimentally the changes of intestinal immunity following shock and resuscitation after trauma. Method:The experimental model was made in rats, which underwent laparotomy, then bleeding and reinfusing through the right fetmoral artery. Result: The concentration of IgA following shock and resuscitation were significantly higher than that before shock.. The concentration of IgA 24 h following resuscitation was the lowest, and was significantly lower than that at the end of shock.. The endotoxin in portal vein following shock and resuscitation were higher than that before shock.. The endotoxin level 24 h following resuscitation was the highest, and markedly higher than that at the end of shock. Conclusion: The traumatic shock and resuscitation are capable of causing intestinal immunosuppression and endotoxemia.