The pressure changes in water and in 20% gelatin blocks produced by bullets of 7.62 mm and 5.56 mm calibre and spherical steel balls of 1.03gm were studied. The pressure was measured by the BJ-100 model transducer.It was demonstrated that there were three peak waves produced when the two kinds of bullets were fired through a water tank. The interval between the two peaks was longer in the waves produced by 7.62mm bullet than in those produced by 5.56mm bullet, the value of The pressure due to 5.56mm bullet was the largest, that due to 7.62mm bullet was the second, and that due to the spherical steel ball was the lowest.The fore-mentioned differences among the pressures produced by different projectiles were closely related to characteristic ballistics of the projectiles. And the pressure value detected and the pattern of the pressure change vary with the transient space eifect and the characteristics of tissue damage.

With a favorable result, we applied Sepharose CL-2B column to the isolation of ribosomal subunit, 50S, from P. Vulgaris cells. This report presents a simple and useful method for preparative separation of subunit species.Ribosomal preparation 225mg (wet wt.) was loaded on Sepharose CL-2B column (inner diameter 20 mm, gel column height 46 cm) which had been previously equilibrated with pH 7.5 Tris-buffer containing Mg2 + O.OOlM and KCl 0.1M. The column was developed with the same buffer. Elution was carried out with a flow rate of 12 ml/h. The adsorbance of the eluate was measured at 258hm. Two peaks were obtained in elution development. The result was checked up to be identical with that observed in ultracentrifuge analysis.According to the proteins contained, the percent recovery of subunit species was 91% in approximate estimation.

Objective To investigate the effect of hypoxia/reoxygenation on apoptosis of rat hypertrophic cardiomyocytes and the metabolic pathway changes of hypertrophic cardiomyocytes by dichloroacetate.Methods The isolated ventricular cardiomyocytes from neonatal Wistar rat were cultured and purified with differential attachment,then BrdU was added to reduce the rate of non-myocytes.The cultured cells were identified by morphology,spontaneous contraction and specific immunocytochemical stain.Hypertrophic cardiomyocyte model induced by angiotensin Ⅱ was set up and assessed by -Leu incorporation.The cultured media were replaced by low glucose DMEM before hypoxia.The cardiomyocytes were incubated at 37 ℃ in an air-tight incubator containing 92% N_(2),5% CO_(2),3% O_(2) for 24 h to simulate hypoxia,then under the condition of 23% O_(2),5% CO_(2) for 4 h to simulate reoxygenation.Apoptotic cells was evaluated by a modified TUNEL assay(DeadEnd~(TM) Colorimetric TUNEL).Results The apoptotic rate of cardiomyocytes increased with time prolongation of hypoxia/reoxygenation(H/R).The apoptotic cell model induced by H/R in rat hypertropic cardiomyocytes was established successfully.When the hypertropic cardiomyocytes were pretreated with Dichloroacetate,the apoptotic rate decreased in a dose-dependent manner.The metabolic pathway changes had effect on the apoptosis of rat hypertrophic cardiomyocytes.Conclusion By collagense digestion,it is convenient to obtain primary neonatal Wistar rat ventricular cardiomyocytes. This method is one of vital research tools in the fields of cardiac hypertrophy.Angiotensin Ⅱ could accelerate cellular proliferation,structural protein biosynthesis and cardiac hypertrophy.Dichloroacetate has the effect of antiapoptosis.

Fifty to 145 ml of No. 2 fluorocarbon blood substitute was intravenously given to 10 normal adult volunteers ( 7 male and 3 female) . Their vital signs were stable during and after the infusion. The ECG, the cardiac, hepatic and renal functions, the mutagenicity test and the routine urine test were maintained in the normal range. NO overt changes in the blood picture except a slight elevation of white count were found at the beginning of the infusion. Transient changes were observed in the function of platelets and the coagulofibrinolytic and immune systems.These results suggest that the infusion of No. 2 fluorocarbon blood substitute is rather safe and the possibility qf its clinical application is great bat further investigation is essential to find out measures to prevent and treat the ana-phylactoid reactions of this fluorocarbon emulsion observed in our study.

35 cases of rotavirus enteritis occurring in months from September to December of 1980 and 1981 were reported. Typical rotavirus particles were found in 35 out of 54 stool specimens examined with electron microscope. The positive rate of EM was 64.8%.The age of the patients was ranged from 4 months to 2 years; 65.7% of them were 6 to 12 months old. There were 22 males and 13 females.The clinical manifestations consisted of diarrhoea, fever(80%), vomiting (62.8%), mild-to-moderate dehydration(85.7%), and metabolic acidosis(37.17%), upper respiratory infection symptoms(4g.57%). In 40% of the cases, the white cells in the feces were increased in number. Secondary bacterial infection occurred in 4 cases( 11%),which was higher than that of other reports.The main route of transmission was fecal-oral; the presence of respiratory symptoms in some patients suggested the possibility of air-borne spreading.The incidence of this disease was low in the new borns. It is most likely that they arc protected with the passive immunity obtained through the placenta. Furthermore, the structural and physiological characteristics of the gastro-intestinal tract of the neonatus are also contributive to reduce the disease in them.

Experience in 19 cases (20 joints) of artificial elbow joint replacement was reported- 15 cases(16 elbow joints) were followed-up more than 25 months.A satisfactory result was obtained in 68.8% of case. This method of treatment has the merits of quick restoration of elbow joiut fuuction and good joint stability. The substituted joint is rather powerful and the range of movement approaches that of a natural one. The operative technique is easy to master.on the basis of follow-up study, the relation ship between the result of treatment and the material used was discussed. The indications and the technique of the operation were presented. The causes of faiture and unsatisfactory results were discussed.

The processes of temporary cavitations produced with 7.62mm bullet, 5.56 mm bullet and 6.35mm spherical steel-pellet in water were recorded with a high speed (8,000 frames per second) camera to investigate the traumatic mechanism of fragments with high velocity and small mass. The temporary cavities produced with above mentioned projectiles were different because of their different ballistic behaviors. The shape and size of the temporary cavitv and the time of its formation were closely related to the density of the adjacent tissues and also to the extent of the tissue damage. Thus the study on the temporary cavitations after projectiles of high velocity but small mass is of clinical significance.

The etiology of acute infantile gastroenteritis in Chongqing area was studied during a 4-year period from 1978 to 1981 The morphologically characteristic rotavirus particles were found in the stool specimens of 63 cases out of 117;specific antibodies against rotavirus was demonstrated in the serum of 52 cases out of 60; and the titer on convalescent serum showed a 4-fold elevation as compared with the titer at the onset of the disease in 28 cases out of 32.On the basis of these findings,it was concluded that the most common pathogen of acute infantile gastroenteritis in Chongqing area in the period from 1978 to 1981 was rotavirus,and the subclinical infection of this virus might be more common than it was.

Objective To study the molecular mechanism of the toxic effect for tetracycline acting on liver using toxicological microarray.Methods Utilizing the mouse toxicological microarray and animal model of tetracycline injuring BALB/c mouse liver,both of which were established by our department,we observed the gene expression profiles in different dose groups and at different time points after tetracycline treatment,and primarily analysed the function of these differentially expressed genes using Gene Ontology Consortium analysis system and hierarchical method.Results Multiple differentially expressed genes were found,and an obvious difference in the profiles was found in those treated with high-dose and low-dose tetracycline.The differentially expressed genes of all time points in high-dose group were divided to four clusters,which respectively related to the molecular mechanism of repressed enegy metabolism,enhanced protein synthesis and degradation,impared system of resisting oxidation,signal transduction genes changing to accelerate apoptosis,repressed genes associated of drug metabolism.Conclusion The analysis using toxicological microarray can offer us many clues on molecular level for studying the mechanism of the toxic effect of tetracycline acting on liver.

The mitochondria of the liver celis of rats are counted following the experimerimental operalion of selective and complete bile duct obstruction. The amount of mitochondria decreases significantly aAcr complele obstruction, (in the control group it is 22.948), and after the seleclive obstruction it decreases significantly, too. This experiment suggests: in the compensatory hypertrophy of the liver the amount of mitochondria dosen't inhance.