Objective:To investigate the effect of the BmK-9-(2) on the sodium current in guinea-pigventricular myocytes. Methods:The whole cell patch-clamp technique was used. Results:The BmK-9-(2)increased the magnitude of the peak inward sodium current (27 ％) ,peak sodium conductace (17 %) and theprolong time course of sodium channel inactivation (8％) and there was no effects on calcium channels.Conclusion:BmK-9-(2) can activate sodium channel and prolong the inactivated course of myocytes.

Objective:In this experiment we used pain-related neurons of Hb unit discharges recording asa standard to observe the effects of prostaglandin E2 (i. p. ) on Hb unit discharges. Methods :The methodsof unit discharges recording and radiant heat induced tail flick responce were used. Results :The dischargesof pain-excited neurons increased after the addition of PGE2 (i. p. ). The discharges of pain-inhibited neu-rons dec reased after the addition of PGE2(i. p. );PGE2(i. p. ) caused the pain threshold to drop after sym-pathetic nerves were destroyed by 6-OHDA. There were no changes of the pain threshold in undestroyedgroup (P＞0.05). The percentage changes of Hb neurons dropped compared with that of undestroyedgroup (P＜0. 05). Conclusion: The PGE2 could change the discharges of pain-related neurons in Hb, inwhich the sympathetic system might participate in the process.

Objective :To study a simplified method of isolation of rat hepatocytes and to observe the pro-cess of cell morphology in long-term culture. Methods :Rat hepatocytes were isolated by a single two-stepperfusion method. The yield and viability were assessed by trypan blue exclusion. [3-(4,5-dimethylthiazol-2-yl)2,5-diphenyl tetrazolium bromide] (MTT) was used to test the effect of serum concentration of newborn calf serum on the proliferation of hepatocytes. Hepatocytes were inoculated in the culture mediumconsisted of Williams' E supplemented with insulin,dexamethasone and 10％ new born calf serum. Themorphologic change of cultured hepatocytes was observed. Results:The average yield of hepatocytes was 2.26× 108 cells per rat, with an average viability of 95.6％. New born calf serum had strong biological activi-ty to stimulate the proliferation of hepatocytes and there was close-effect relationship followed by the in-crease of new born calf serum concentration. The rat hepatocytes can be cultured for 5～ 6 weeks withpreservation of normal morphologic appearance. Conclusion:The rat hepatocytes isolated by the abovemethod have high yields and viability and can be long-term cultured in vitro.

Objective :Humna WAF1 gene was cloned,and WAF1-pcDNA3 recombinant plasmid was con-structed. Methods :Human WAF1 gene was amplified by RT-PCR from Hela cell,then cloned into pcDNA3vector. Results :Human WAF1-pcDNA3 recombinant plasmid was constructed,and DNA direct sequencingindicated that was correct. Conclusion:Our study laid the foundation for studying WAF1 gene expressionand it＇s biological effects.

Objective:To study histocompatibility of self-made stents made of NiTi alloy in rabbits.Methods: To place 30 stents made of NiTi alloy into 30 rabbits trachea through mouth under general anethesia,to observe local tissue reaction from 1 week to 6 months and to try to find pathological changes of main organs of rabbits in the 6 th month. Results:During observation,apart from dyspnea in two rabbits,one died at 3 day and the other died at 6 week after implantation. Autopsy showed the implanta.tion sites were occluded by granulation tissue. All other rabbits were normal and implantation sites were patent. In the first three weeks we could observe acute inflammation at the implantation sites while after 5 weeks we could observe chronic inflammation there. We observed that the structure of epithelial cells tended to be normal by telemicroscope. There are no pathological changes in liver, spleen, kidney, lung, heart and brain tissue. Conclusion:Self-expanding stents possess good histocompatibility and have no toxic reaction to whole body and fit to implantation into human body.

Objertive:To search for the measures of improving the effects on aesthetics of front teethmetal-poircelain crown. Method:The causes and mechanisms of different effects on aesthetics of front teethmetalprocelain crowns in 52 cases were analyzed. Resuts:The main causes that influenced aesthetics offront metalporcelain crown were out of color and bad imitation of teeth. Conclusion: Important factors thatimprove the effects on aesthetics of front teeth metal-porcelain crown include the design and the prepara-tion of cervical layer,accurate choice of the color and correct making process.

Objective: To study the clinical therapeutic characteristics of myasthenia gravis (MG) with hyperthyroidism and the effects of surgical procedures for the patients. Methods:Subtotal thyroidectomy,thymectomy,and simultaneous subtotal thyroidectomy and thymectomywere performed on eleven patients with MG and hyperthyroidism. These patients were followedup after the operation. Results :The neck incisions were infected in two of seven type Ⅱ b patientsdue to trachestomy and the infected incisions were surgically healed. The MG symptoms of threecases (1 cases in type Ⅱ. and 2 cases in type Ⅱ b) relapsed in 3 to 6 months after subtotal thy-roidectomy. The MG symptoms of 2 cases (1 case in type Ⅱa and 1 case in type Ⅱ b) relapsed in 8to 12 months after thymectomy. Among six patients treated by simultaneous subtotal thyroidecto-my and thymectomy,the MG symptoms relapsed in a type I case 3 months after the operation,remitted in three case (1 case in type Ⅱ, and 2 cases in type Ⅱb) and improved in two type Ⅱ bcases since the operations. Conclusion:The simultaneous subtotal thymectomy and thyroidectomyfor patients with MG and hyperthyroidism might have better effects,although infective opportuni-ty of the neck incisions increased owing to trachestomy. However,the prognostic effects were notvery satisfactory whether simple subtotal thyroidectomy or thymectomy for the patients with MGand hyperthyroidism was performed.

Objective:To study the methods of early qualitative diagnosis of laryngeal displasia and earlycarcinoma. Methods:We investigated displasia (34 cases),squamous cell carcimoa (19 cases) and vocalcord polyps (17 cases) of larynx which were embeded in paraffin by PCR－SSCP analysis of p53 gene,im－munochemi stain of p53 protein and Ⅳ collagen,cytometer (determining fraction of cell cycle) and AgNORstain. Results :Eleven of 34 cases of displasia were all positive in the indexes. Seven of 11 cases were alsopositive in pathology,but others were negative. Five of 34 cases of displasia were all negative in the index-es,2 of 5 cases were positive and 1 of 5 cases were negative,other two cases did not have following-up re-sults in pathology. Conclusion :The results suggest that it is the combination of the morphological indexeswith biological indexe that is more scientific and more accurate in quatitative diagnosis of premalignantchange.

Objective:We estimated the effect of Xinxuetong on the left ventricular function in hyperten-sion. Methods :Transaortic and transmitral flow velocity was studied by pulsed Doppler echo cardiographybefore and after vein administration of Xinxuetong. Results: It was shown that Peak A, IRP andPeak A/Peak E decreased after administration of Xinxuetong. Conclusion:This study suggests that Xinx-uetong can significantly improve the diastolic function and the treatment of hypertension.

Objective:To study the effect of thyroid function on bone metabolism. Methods:Serum FT3,FT4 were investigated by radioimmunoassay (RIA) and bone mineral density of spine (L2～4) weremeasured by dual energy x-ray absorptinmetry and other markers related to bone metabolism were alsomonitored in 30 patients with hyperthyroidism and 30 healthy volunteers. Results :The levels of FT3,FT4,ALP were significantly higher than those of the normal controls. BMD of spine decreased significantly incomparison with the controls ,and the degree of severity and incidence increased with age. Conclusion:Thy-roid hormone might speed up bone turnover directly with increased bone resorption to induce bone massloss.