Bile acid efflux pump(BSEP)is the major transporter of bile salts secreted by liver cells into the bile,the variation and inhibition of which are connected with cholestasis and drug-induced liver injury.A deep understanding of the physiological and pathological function of BSEP IS achieved by analysis and summary of diseases.The paper briefly illustrates the structure, expression,regulation,substrates,inhibitors and diseases of BSEP,in order to provide further theoretical and experimental basis for the clinical treatment.

Objective To construct recombinant plasmids containing HPV18E7 gene ,and explore the optimization condition of its expression in Escherichia coli .Methods The genomic DNA extracted from HeLa cell line which served as a template to the HPV18 E7 gene was amplified using PCR method ;and the amplified product of HPV18E7 gene was connected to the pET-32a(+ ) vector ,which composed the pET-32a(+ )-HPV18E7 recombinant plasmid ;the positive recombinant plasmids were transformed into BL21-DE3-pLysS competent cells and the optimized expression condition was explored in order to obtain a large amount of HPV18E7 oncogenic protein .Results The fragment length of PCR products of HeLa cell genomic DNA was consistent with that of HPV18 E7 gene .In LB medium ,the expression level of the target protein was not high under such conditions as different concentra-tion of IPTG and lactose ,different temperatures and different induction starting amount .Therefore the ZYM-5052 auto-induction medium was tried in this experiment ,and the expression amount of the fusion protein was much higher than that induced with IPTG and lactose .Conclusion The amount of HPV18E7 fusion protein in ZYM-5052 automatic induction medium is much higher than that induced with IPTG and lactose .

[Objective]To study the methods and opportunity of operation for the malignant tumor intercurrent fracture of extremity.[Method]Seventeen cases of malignant tumor intercurrent fracture of extremity were reviewed in our hospital from June 1996 to October 2003 in the study,which included osteosareoma 4 cases,giant cell tumor 3 cases,ewing tumor 1 case,ametoblastoma of bone Ⅰ case,bony metastases 8 eases.4 cases treated with exterior fixation and chemotherapy in Ⅰ P(period)and reconstruction alter tumor cutting in ⅡP(period),11 cases treated tumor eliminate and reconstruction in Ⅰ P(period).One case amputed in Ⅰ P(period)and 1 case amputed in Ⅱ P(period).[Result]All patients treated had been followed up from 12 to 88 months.One case occurred local rccurrrenee.and 2 cases died because of lung metastases in the 9 cases of primary malignant tumor.While 1 case occurred local reecurrenee and 4 cases died in the 8 cases of metastasis malignant tumor.[Conclusion]For the primary,malignant tumors with fracture.which were sensitive to chemotherapy,should first take into account to exterior fixation and chemotherapy inⅠ P(period)and reconstruction after tumor cutting in ⅡP(period),while for the insensitive giant cell tumor and bony metastases with fracture should be treated with tumor eliminate and reconstruction in ⅠP(period).