Polyethylene has been used as materials for artificial hip or knee for more than 40 years. It has low friction factor,wear rate,good mechanical function and biocompatibility. However,polyethylene wearing particle-caused local interface osteolysis,resulting in aseptic loosening is the primary reason for artificial hip replacement failure. To improve friction performance of artificial hip joint,joint prosthesis assembly interface such as metal to metal and ceramics to ceramics has arouse more attention. Linear friction rate of metal to metal artificial hip is one percent of metal to ultrahigh molecular polyethylene,but metal to metal artificial hip joint has stress shielding effect and potential toxicity. Ceramics has good biocompatibility,low friction coefficient,and wear-resistance,but lined ceramics breakage affects long-term effect of ceramics to ceramics artificial hip joint. To improve material function,explore prosthesis surface modification,and know biological friction and lubrication mechanism are important issues in current studies.

Corneal epithelial cells,lens epithelial cells,and retinal pigment epithelium cells contain a vast array of ion channels and pumps.The selective permeability to different ions generates endogenous electric fields and currents in those tissues.Abnormalities in the endogenous electric fields may underlie many ocular diseases,for example chronic corneal ulcers,posterior capsule opacity after cataract surgery,and retinopathies.How the electric fields influence the tissues and cells and participate in the occurrence of the ocular diseases is a hotspot of research in this field.This article briefly reviewed the mechanism of how the endogenous electrical activities are generated,the responses of ocular cells to applied electric fields,potential intracellular signaling mechanisms and clinical implications.Further understanding of this aspect is likely to offer new insights into ocular diseases.

Objective To study the value of contrast enhanced ultrasound in identifying cirrhosis combined with small lesions in the liver .Methods A retrospective analysis of patients with small lesions in liver cirrhosis were 72 cases,including 82 lesions.All patients were routine ultrasound and angiography .Results 49 cases of liver cirrho-sis with benign lesions for the performance of ultrasound contrast enhancement phase were synchronized with the liver parenchyma ,33 cases of liver cirrhosis with malignant lesions in the arterial phase showed a rapid and uniform enhancement .Benign lesions and malignant lesions were no significant differences in the timing of the beginning of growth(t=0.812,P>0.05).The peak time,enhance time before they eliminate time aspects of malignant lesion group were less benign lesion group (t=2.836,3.771,7.062,P<0.05,P<0.01).The sensitivity,specificity and accuracy through conventional ultrasound were 46.9%,76.2%,68.3%.The sensitivity, specificity, and accuracy through contrast enhanced ultrasound were 97.1%,97.8%,97.6%.Ultrasound contrast sensitivity ,specificity,accu-racy were higher(χ2 =5.36,7.22,8.04,all P<0.05).Conclusion Contrast enhanced ultrasound can more accu-rately identify nature of small lesions of liver cirrhosis .

Large quantities of recent researches show abnormal expression of epidermal growth factor receptor (EGFR)in different solid tumors. An especial relationship between EGFR expression and tumor cell proliferation, angiogenesis, invasive ability metastasis and apoptosis has been established. Tarceva, is an epidermal growth factor tyrosine kinase reversible inhibitor, which blocks signal transduction by inhibiting the tyrosine kinase phosphorylation and thus inhibits tumor growth. Tarceva is now proved to have certain therapeutic effects on non-small cell lung carcinoma ( NSCLC ), however, it has not shown a convincing effect when applied in gli omas and other tumors. Now the research of the combination with Tarceva and other anti-tumor drugs has come into the focus. Combination therapy with Tarceva and other chemotherapeutic drugs or other means might be an effective alternative.

Objective To elucidate the death cause of automoble drivers and provide a scientific basis of preventing occupational disease for automobile drivers.Method A cohort analysis method of accupational epidemological study restropectively was used to the investigate.Results Main death causes were as follows:the first death cause was cardiovascular system disease,the second was malignant tumors,accouted for 40 91% and 38 6% respectively.Conclusion Higher death rate of circulation system disease,malignant tumors and unexpected accidents for automobile drivers was demostrated in the accupational disease epidemological inestigation.

Objective To investigate the effect of abnormal ventricular wall motion caused by chronic coronary artery insufficient blood supply on hemodynamics.Methods Of 44 cases with chronic coronary artery disease affirmed by clinical symptoms and electrocardio gram,32 cases had abnormal ventricular motion shown by ultrasonic cardiograph.The detection of hemodynamics was performed in those patients,which were analyzed and compared.Results Indexes of hemodynamics showed mild and moderate abnormality in 32 abnormal ventricular wall motion cases.Conclusion The hemodynamics was abnormal in patients with abnormal ventricular wall motion caused by chronic coronary artery insufficiency.

Objective : To study the perioperative changes of the plasma NO and ET- 1 in the patients with the portal hypertension after splenorenal shunt operation. Me thod s: The plasma NO and ET- 1 of the perioperative period was detected in the cirrhotic patients with portal hypertension after distal splenorenal shunt, NO was masuredusing the Griesss and ET- 1 by the radioim- munoassay. R e su lts: Compared with control group and cirhosis group,plasma ET- 1 and NO levels significantly increased in portal hypertension group. Compared with preoperative levels, plasma NO and ET- 1 levels significantly decreased in the patients with portal hypertension after surgery ( P

The sensitizing effects of 16 porphyrins on photooxidation of NADPH were studied.It was suggested by the experimental results that the sensitizing effects were related to the chemical structure of porphyrins.Some of the meso-tetra(sub-stituted-phenyl)porphines and chlorin derivative pheophorbide a were more powerful photosensitizing agents and the sensitizing effects of most of semisynthes-ized hematoporphyrin derivatives were generally the same as PsD-007 or YHpD and lower than those of porphines and chlorin derivative.

Objective:To recognize the diagnostic value of emergency unenhanced CT without oral contrast material in the diagnosis of infrequent abdomen injury.Methods:990 patients with abdomen symptoms underwent plain scan using 16-row spiral CT without oral contrast material;their CT pictures were noted to find adrenal gland,pancreas,and hollow viscus injure.All cases underwent laparotomy or follow-up CT visit.The initial CT results were compared with the operative and follow-up outcome.Results:In the 990 patients with abdomen symptoms,there were 12 cases of adrenal gland injuries;17 cases of pancreas injuries,and 26 cases of hollow viscus injuries.Compared with operative and follow-up outcome,there was 0 false-negative and 0 false-positive in adrenal gland injury and the sensitivity was 100%;there were 2 false-negatives and 3 false-positives in pancreas injury and the sensitivity was 83.3%;there were 6 false-negatives and 7 false-positives in hollow visceral injury and the sensitivity was 76%.Conclusion:16-slice spiral CT has high diagnostic value in acute infrequent abdomen injury,The diagonostic sensitivity is higher to adrenal gland injury,but relatively lower to hollow viscus injury.

Objective:To study the expreesion of PPAR-? in the left ventricular myocardium in rats with myocardial infarction,and to investiagate whether the mechanism of Irbesartan reversing the ventricular remodeling is related to PPAR-?.Methods:Myocardial infarction models were successfully induced by ligation of anterior descending coronary artery.24 h later the survivors were randomly divided into 3 groups.① MI group;② Irbesartan group 75 mg/(kg?d);③ The rats with sham ligation formed Sham group.After 6 weeks,the expreesion of PPAR-?,the ratio of LV weight to body weight(LVWI),cross-section area(CSA)of left ventricular myocardium were examined.The collagen volume fraction(CVF) were analyzed by PSR dyeing.Results:In MI group,compared with those in Sham group,the expreesion of PPAR-?mRNA and protein in the left ventricular myocardium decraced significantly,but the LVWI,CSA and the CVF in non-infarcted zone increased.Compared with those in MI group,in Ire group,the expreesion of PPAR-?mRNA and protein in cadiocyte incraced,while the LVWI 、CSA and the CVF in non-infarcted zone decreased.Conculusion:The expression of PPAR-? is down-regulated in the left ventricular myocardium with myocardial infarction,Irbesartan reverses the left ventricular remodeling possibly by up-regulating and activating PPAR-?.