Objective:To investigate the role of CCR5 key residues as a co-recptor for the cellular entry of human immunodeficiency virus type Ⅰ(HIV-Ⅰ).Methods: Mutation of amino acids was introduced in different extracellular loops of CCR5 by site-directed mutagenesis technique,turning the non-polar amino acids into polar ones,the non-hydrophilic into hydrophilic,and the aromatic into non-aromatic.The mutants of CCR5 were expressed in BamHⅠ/XhoⅠ and were allowed to bind with gp120,and the binding activity of the mutants was compared with that of wild-type CCR5.Results: The coreceptor activity of CCR5 was reduced greatly when Cys in the first extracellular loop was replaced by Tyr and Pro in the third extracellular loop was replaced by Ser.There was no obvious change in the coreceptor activity of CCR5 when other replacements were introduced.Conclusion: HIV-Ⅰ virus needs receptor and co-receptor to achieve its cellular entry.CCR5 is a co-receptor and some of its extracellular loop amino acids are essential for gp120 recognition of HIV-Ⅰ.

Objective To investigate the effect of long-term cardiac rehabilitation on risk factors with doctor supervision after percutaneous coronary intervention(PCI). Methods One hundred and twelve patients after PCI were divided into the cardiac rehabilitation group(56 cases) and the control group (56 cases). All of the patients were given medication and health education, meanwhile the cardiac rehabilitation group received 4～6 weeks hospitalized cardiac rehabilitation program and one year ambulatory cardiac rehabilitation with doctor supervision. Risk factors were assessed six mouths and twelve mouths after the treatment. Results The risk factors except diastolic blood pressure and body weight index improved more significantly in the cardiac rehabilitation group than in the control group. Clinical event in the cardiac rehabilitation group is lower than in the control group. Conclusion Long-term cardiac rehabilitation with doctor supervision is safe, efficiency and good compliance to improve risk factors of coronary heart disease after PCI except diastolic blood pressure and weight management.

Objective To investigate the relenvant factors of precocious puberty and provide the basis for precaution of high risk group of precocious puberty .Methods A 1:1 case-control study was performed on 50 healthy girls and 50 precocious puberty girls .Results Univariate analysis showed an significant differences in the exposure rates of following five factors between cases and controls:intake of nutritious and health products ,favoring meat and poultry,long time watching television,addiction to TV ads,family economic condition (The Chi-square values are 7.045,9.073,17.478,14.063,12.246 respectively,all P<0.05).The Logisitc regression showed that favoring meat and poultry,long time watching television and addiction to TV ads had significant differences among precocious puber -ty children(The Wald′s Value were 4.846,6.850,5.662 respectively,all P<0.05).Conclusion favoring meat and poultry,long time watching television and addiction to TV play an important roles in precocious puberty .

Objectives:This study aims to summarize the research progress of multiple-site physician practice to determine further research directions. Methods:Literature on Chinese multiple-site physician practice between 1949 and 2013 was obtained from CNKI, Wan fang database and CQVIP database, the annual volume distribution of se-lected documents was been described and the topics and content of literature cited at least once were summarized through literature content analysis. Results:The volume of literature increased rapidly from 2009, guided by related government policies. Content analysis is insufficient in the research areas of supporting policies, international experi-ences, relevant laws and empirical studies. Suggestions: Further research should focus on multiple-site physician practice policies themselves and supporting policy analysis, international comparisons of multiple-site physician prac-tice systems, studies into relevant laws and regulations and empirical studies based on quantitative methods.

Objective:This study aims to ensure the private hospitals development strategy in the background of new healthcare reform and put forward some scientific suggestions to help promote their sustainable development. Methods:The SWOT analysis method was adopted to analyze the private hospitals’ internal strength, weakness, exter-nal opportunity and threats. Results: The results showed a clear property right, advanced management system and other outstanding advantages in the private hospitals. Opportunities like the improved policy environment and people’s medical demand expansion are also very prominent. Meanwhile, the private hospitals development also faces some disadvantages and challenges such as illegal operation, disorder in the market competition, vague orientation, etc. Conclusions:It suggests the strengthening of the personnel and hospital culture construction, adoption of the differen-tiation strategy, improvement of the diagnosis and treatment ability, etc.

Objective:Our aim was to To clarify the roles of p16 and p15 proteins in the genesis of acute lymphoblastic leukemia(ALL).Methods:Twenty-three samples of ALL were studied by the method of indirect immunofluorescence.Flow cytometer was used to estimate the cellular fluorescent intensity to determine the levels of p16 and p15 proteins.Results:Negative expression for p16 protein was found in 10 of 23 samples,and 8 of 23 were p15 negative expression.Both kinds of proteins were abscent in 6 samples.2 of 3 cases of T-ALL were negative expression of p16,p15 protein.In non T-ALL,6 of 13 were negative expression for p16 protein,5 of 13 were p15 protein deficient.The expression rates of p16,p15 protein in high leukocyte group were lower than those of non-high leukocyte group(P<0.05).The expression rates of p16,p15 proteins in HR-ALL were lower than those of SR-ALL(P<0.05).Conclusion:The p16 and p15 proteins take part in the genesis of ALL.Negative expression of p16,p15 proteins might imply the poor clinical outcome.

Objective To design an instrument that can provide a series of pulse to stimulate cell by means of external electric field, the structure and function of organism can retrieve. Methods AVR MCU, produced by America ATMEL Co., is used as the core of the system. The program has been developed to adjust three pulse's parameters, including amplitude, frequency and pulse duration. The cooperation between DAC and OP completes the transformation from monopole pulse to bipolar pulse. The booster PB50 amplifies the current and voltage of the output. Results The Stimulator can provide bipolar pulse, amplitude: up to ?40V, frequency: 0.01Hz -10Hz, pulse duration: 0.4ms -24ms. Conclusion Cooperating with special electrode board, the instrument can provide effective electric field for cell simulating. At present the instrument has been used in the research of the endothelial progenitor cell.

Objective To find out present condition and differences in implementation of clinical pathways in hospitals of in China.Methods "Clinical pathway" was entered as a keyword to search in PubMed NCBI Chinese Science and Technology Periodical Database for related literatures in China from 1999 to 2009,analyzing the general implementations of clinical pathways in hospitals in different areas using the SPSS12.0 software.Results A total of 1051 relevant literatures were found.Through data analysis of these literature,differences of implementation of clinical pathways were found for 162 hospitals of different areas.It was found that the differences of total diseases among China's East,West and Central areas are significant statically.Diseases of implementation per hospital in the Central average 16.8,those in the East 8 types,while those for the West 4.4.Tertiary hospitals account for 70% as the main force of clinical pathway implementation,with diseases of implementation up to 13.7,while that under tertiary level down to 2.8.Conclusions Implementation of clinical pathways varies significantly among hospitals in different areas in China.In the process of implementing clinical pathway,appropriate management strategies should be developed according to actual situation in different hospitals in light of policies,hospital management and patient considerations.

Implementation of clinical pathways has a natural tie with payment modes of medical insurance,as various payment modes apply different impacts on clinical pathway.This article compared the strengths and weaknesses of various payment modes,and analyzed their impacts on clinical pathway.This way the authors provide references for decision makers of medical insurance policy.

Objective To study the expression and significance of Ki-67 in gastrointestinal stromal tumors(GIST) with CD117 immunoreactive. Methods The expression of Ki-67 was detected by SP method in 25 cases of high risk GISTS, 18 cases of moderate GISTS and 33 cases of extremely low and low risk GISTS,which were compared with the follow-up results. The relationship between Ki-67 index (LI) and risk degree was analyzed. Results Forty patients with moderate and high risk GIST were followed-up, including 26 alive,12 die of GIST and 2 die of other causes. Compared with patients of extremely low and low risk GIST, Ki-67 LI＞5 % was correlated with moderate and high risk cases (P ＜0.01), meanwhile Ki-67 LI was positively correlated with tumor sizes of ＞5 cm and tumor mitotic cell count ＞5/50 HPF, but was not with locations(P ＞0.05). Conclusion Ki-67 LI＞5 %, tumor size＞5 cm and tumor mitotic cell count＞5/50 HPF are risk indicator for GIST with CD117 immunoreactive.