The paper gives a detailed description of the main features of American medical services,the characteristics of American hospitals,the responsibilities of hospital presidents and the problems faced by them.In addition,it introduces the macro-management of American hospitals and the existing problems.

Objective To investigate the relationship between myeloid-derived suppressor cell ( MDSC) levels and immune function and hepatitis B virus DNA ( HBV-DNA) replication level in patients with hepatitis B. Methods 96 patients with hepatitis B were included in the study.40 normal persons who received physical examina-tion in the hospital during the same period were included as the control group.The content of MDSC was detected by flow cytometry and HBV-DNA level was detected by real-time fluorescence quantitative PCR technique.Statistical analysis was performed.Results The content of MDCS in hepatitis B group (8.77 ±3.69)%was significantly high-er than (1.64 ±1.26)%in the control group (t=16.80,P<0.05).The content of MDCS in HBsAg positive group (11.29 ±3.39)%was significantly higher than (4.71 ±2.88)%in HBsAg negative group (t=10.76,P<0.05). The proportions of HBA DNA<103 IU/mL,103 -104 IU/mL and 105 -106 IU/mL in HBsAg positive group(0.00%, 0.00%,9.09%) were significantly lower than those in HBsAg negative group (54.05%,22.97%,20.27%),while the proportion of HBA DNA>107 IU/mL ( 90.91%) was significantly higher than that in HBsAg negative group (2.70%)(P<0.05).The content of MDSC in HBV DNA positive group[(10.82 ±3.26)%] was significantly higher than that in HBV DNA negative group[(5.84 ±2.16)%](t=8.42,P<0.05).Spearman's correlation analy-sis showed that the level of MDCS expression was positively correlated with the level of DNA replication (r=0.769, P<0.05).Conclusion The increased level of MDSC content can cause the immune suppression and is positively correlated with the degree of HBV DNA replication.

Objective: To establish the assay of berberine hydrochloride for Sanhuang Tablets (Radix et Rhizoma Rhei, Extractum Scutellariae and berberine hydrochloride). Methods:The HPLC with a KF C 18 column (250mm?4.6mm,10?m) was used. Acetonitrile-0.05 mol?L -1 triethylamine buffer solution (adjusted pH to 3.0 with conc. H 3PO 4) (35∶65) was used as mobile phase. The flow rate was 1.0mL?min -1 , and the detection wavelength was at 347nm. Results: The method has a good linear dependuce. The average recovery of loading sample was 98.21% with RSD 1.01%. ( n =9). Conclusion: The method is convenient for a good resolution and can be used for the quality control of Sanhuang Tablets.

0.05); and more 5 years,length of service also between doctors. There were 98.3% of medical staffs being aware of health care law for six-step hand-washing and hand hygiene 97.8% being aware of hand hygiene compliance and 86.7% obtained knowledge after proper training,but most of them did not know the relationship between hand hygiene and hospital infection. CONCLUSIONS A good hand hygiene compliance need not only a reliable and convenient environment,but also training,inspection,supervision and management.

OBJECTIVE: To observe the effects of combined application of Radix Salviae Miltiorrhizae injection and dopamine injection on peritoneal dialysis patients.METHODS: By self-control method,the peritoneal dialysis solution of 22 patients with ambulant continued peritoneal dialysis was added with 20 mg dopamine injection and 12 mL Radix Salviae Miltiorrhizae injection for dialysis of 14 days.The D/P values of urea nitrogen(UN) and creatinine(Cr),week's peritoneal UN clearance index(KT/V),the clearance rate of Cr(Ccr),week's total KT/V,Ccr,reabsorption rate of glucose and the net amount of 24 hours' ultrafiltration were recorded before and after medication.RESULTS: The addition of dopamine injection and Radix Salviae Miltiorrhizae injection to the peritoneal dialysis solution resulted in significant higher values in week's peritoneal KT/V,Ccr and week's total KT/V,Ccr and the net amount of 24 hours' ultrafiltration as compared with before medication(P

Executive function is an important advanced cognitive process, and it is the function that integrates different cognitive processes to achieve one's aim. Updating is an important component of executive function. According to the classifications of Miyake & Colletee on executive function, two study paradigms on memory updating are discussed: n-back paradigm & running memory paradigm. A new study method called latent variable analysis and new studies of cognitive neuroscience on memory updating are introduced. Issues on ethics and morality in research on cognitive experiment of psychology are briefly demonstrated to explore appropriate direction for research of executive function in future.

Objective To study the effect of follicle stimulating hormone(FSH)on the secretion of anti-mullerian hormone(AMH)in granulosa cells in patients with polycystic ovarian syndrome(PCOS).Methods From Aug.2008 to Dec.2009,33 patients with PCOS in Reproductive Medicine Research Center,Sixth Affiliated Hospital of Sun Yat-sen University were collected from 8-10 mm antral follicles and classified into the following three groups: FSH-unstimulated granulosa cells(unstimulated group,n =12),exogenous FSH-stimulated granulosa cells(exo-stimulated group,n =12)and internal FSH-stimulated granulosa cells(int-stimulated group,n =21).ELISA and real-time PCR were relatively used to measure protein and mRNA level of AMH.Luciferase reporting vector was constructed to detect the promoter activity of AMH.Results The levels of AMH secretion in PCOS granulosa cells were(11.4 ± 4.0)μg/L in unstimulated group,(7.9 ± 1.1)μg/L in exo-stimulated group and(5.6 ± 1.7)μg/L in int-stimulated group.Both the external and internal stimulation of FSH may suppress AMH secretion significantly(P ＜0.05).The mRNA level of AMH in PCOS granulosa cells were 2.5 ± 1.2 in unstimulated group,which were higher than 1.5 ± 0.5 in exo-stimulated group and 1.1 ± 0.7 in int-stimulated group significantly(P ＜0.05).The luciferase activity of AMH in PCOS granulosa cells were 11.5 ± 2.3 in unstimulated group,8.7 ± 2.4 in exo-stimulated group and 6.8 ± 2.4 in int-stimulated group.The luciferase activity of AMH in unstimulated group was significantly higher than those in exo-stimulated and int-stimulated groups(P ＜0.05).Conclusion FSH may inhibit the excessive secretion of AMH and stimulate follicle growth in PCOS granulosa cells by suppressing activity and expression of promoter.

Telomerase can inhibit the shortening of telomere and stimulate continuous cell proliferation to form tumor.The activity of telomerase can be prohibited by G-quadruplex formed by the single chain in G-rich field of telomere 3' end, resulting in tumor cell apoptosis.Ligands which can induce the formation or stabilize the structure of G-quadruplex in G-rich field of oncogene exhibit antitumor function. Nowadays it becomes the core concern of chemists and biologists to screen and structurally design the compounds targeting G-quadruplex.This paper summarized the discoveries in the G-quadruplex-targeted telomerase inhibitors in recent years.

Multiglycosidorum Triptergii are widely used in China. We treated 37potients who had suffered from child asthma for 12 weeks with this drug (1.0～1.5mg/kgday) and observed for about 8 months. The results showed that 33 of them were curedor relieved. The effective rate was 89.18%. In order to study its immune mechanism, the percentage of T subsets and T supperessive rate were measured for 27 patients.Theresults showed that CD3~3 and CD4~4 subpopulation had no change,but the percentage ofCD8~+ increased from 25.36?5.16% to 28.96?3.03%,the ratio of CD4~+/CD8~+ declined(P

Objective:To study the mesiodistal teeth size and the relationship between upper and lower teeth dimension of normal occlusion from Han Chinese in Xi'an. Methods: 52 males and 55 females with normal occlusion were selected. The mesiodistal width of each tooth was measured using a vernier gauge caliper. Statistical analysis was performed. Results: For the 107 cases with normal occlusion, the mean and standard deviation of the teeth size were calculated. There were significant differences between males and females in maxillary incisors, canines, first molar and mandibular canines, premolars. The normal range was obtained for the anterior and overall tooth size ratio(anterior ratio:78.32?3.01 overall ratio:91.10?2.27); and the regression equation that was used to quantify the tooth size discrepancies was expressed according to the significant correlation between the upper and lower tooth (r anterior=0.754, rtotal=0.851). Conclusion: There is a relationship between upper and lower teeth dimension. Sex difference should be considered when tooth size was used in clinic.