[Objective]To discuss the midterm effects of bipolar artificial femoral head arthroplasty in treatment of elder femoral neck fracture.[Method]From September 1995 to Febuary 2005,73 elderly patients with femoral neck fracture were operated with domestic bipolar artificial femoral head arthroplasty (average 74 years old).Forty-seven cases had been followed up for average 65 months.Harris score system and X-ray had been used for evaluation.[Result]There was no vessel and nerve injury,no infection and dislocation,no perioperative death.The complications included one greater trochanteric fracture,3 cases with pneumonitis,2 urinary infection,1 cerebral infarction,1 dysfunction in central nerve system and 1 case with deep venous thrombosis.Of all the 36 X-rays there were 3 cases with prosthesis subsidence,lucent line lesser 2mm in 2 cases,narrow joint space in 21 cases,protrusion in 1 case.According to the Harris scoring system,there were excellent in 12,good in 26,fair in 7,poor in 2.[Conclusion]Bipolar artificial femoral head arthroplasty are reasonable choice for treatment of femoral neck fracture in the elderly.Proper indication and perioperative management is critical to get good results.

The purpose of this study is to evaluate the interaction effects of In-Chen-How (Artemisia capillaries Thunb.) on the pharmacokinetics of acetaminophen and on liver microsomal cytochrome P450 enzyme activity in rats. The rats were divided into control group (n=8) without In-Chen-How and the pretreated group (n=8) administered with In-Chen-How (approximately 1.0 mL·kg-1, according to weight) for 5 consecutive days. Rats in the control group received water simultaneously. Each rat was then given acetaminophen. The pharmacokinetic parameters of acetaminophen of the two groups were significantly different. In the In-Chen-How pretreated group, the maximum concentration of acetaminophen and the area under the plasma concentration-time curve were reduced about 58.4%, 56.7% and 55.4%. To further explain the results, liver microsomal suspensions were obtained from rats that were randomly divided into control and In-Chen-How pretreated group. The levels of CYP1A2 and CYP2E1 in hepatic microsomal protein from pretreated group were increased as compared to that from the control group. It indicated that In-Chen-How can stimulate the activity of CYP isozymes. The changes in the pharmacokinetics of acetaminophen resulting from the administration of In-Chen-How are related to an increase in metabolic activity of CYP1A2 and CYP2E1.