After testing the resistance of Streptomycin to the strain NS-41-80 which is the Meilingmycin producer- Streptomyces nanchangensis , a lot of streptomycin-resistant ( str ) mutants were screened after the spores regenerated on the lethal media when they were treated with 4 different dosage of super-mutagent EMS. We have abtained the high-yield strain 80-5. 11-221 from these str mutants which only produces Meilingmycin and no Nanchangmycin in the rotation-flask experiments. The productivity of 80-5. 11-221 is 1521?g/mL 77. 9% higher than CK's 855?g/mL. After the shake flask fermentation experiment of 80-5. 11-221 for six generations, the productivity of F 2 and F 3 is stable and the productivity of F 4?F 5?F 6 decreases hastily with the increment of generations. It was showed that the chemical-resistance mutation of the strains had closely relation with yield mutation and the EMS dosage of the yield mutation was higher than the resistance-chemical mutation's through the statistical analysis between the dosage of mutation and the chemical-resistance mutational frequency?the variate capacity of the mutants' yield. A model of the resistance-chemical mutational labelling rational selection of the strain producing Meilingmycin was established.

The influence of medium variety、thermal treatment of the soil samples and inhibitor to the isolation effect of actinomycetes was studied by plate paint isolation methods.The results showed that: ①The isolation results of gauze No.1(GA) and straw decay substance agar(SDSA) might reflect basic station of soil actinomycetes. ②Thermal treatment (120℃?1.0h)in soils might promote actinomycetes spore sprouting and increase the quantity and variety of actinomycetes. The quantity and varieties of actinomycetes in the Soils that were treated with 120℃?1.0h were increased by 5.5%～54.9% and 12.5%～100% than the check of none-thermal treatment respectively. But thermal treatment had no effect on reduce the quantity of bacteria. ③The quantity of bacteria had significant reduction by adding 75?g/mL K 2Cr 2O 7 and 1～3?g/mL penicillin at same time to the isolation medium, and had little effect on the quantity and varieties of actinomycetes. Actinomycetes quantity (?10 6cfu/g) and variety of the treating of 75?g/mL K 2Cr 2O 7 and 1～3?g/mL penicillin in No.1 soil on SDSA medium had reductions by 0～58.8% and 0～18.2% compared with treating of 75?g/mL K 2Cr 2O 7, respectively. ④streptomycin might not been used for bacterteria inhabitor in the isolation of actinomycetes.

Objective To summarize the epidemiological feature of plague cases oceuwed in China.Methods The epidemiological and clinical data from 1981 to 2006 year in China were analyzed with descriptive study method.Result Nine hundred and seveneteen human plague cases were diagnosed in 9 provinces(regions) from 1981 to 2006 years,105 cases died,the mortality rate being 11.45%,and they distributed in 69 counties (cities or banners).In Qinghai Province 108 cases were diagnosed,the mortality rate was 46.30%(50/108),the cases distributed in 17 counties(cities);137 cans in Guizhou,distributing in 2 counties(cities);517 cases in Yunnan,distributing in 26 counties(cities).Plague cases peaked separately in 1983,1990,1996 and 2000 years,they were 25,75,98 and 254 separately.The principal spreading ways were breathing flying particles,touching,skinning and eating marmot in Qinghai;750 cases were of bubonic plague,among whom 4 cases in Tibet died,the fatality rate was 0.53(4/750);121 cases were of pneumonic prague,among whom 65 cases died,was accounting for 53.72%(65/121);31 cases were of septieaemic plague,and 30 cases died(one cases was cured in Inner Mongolia),accounting for 96.77%(30/31).Others were brain plague,intestinal plague,tonsil plague and plague cellulites,which were cured.Conclusion From 1990,human plague epidemical scope and intensity is enlarging continuously compared with 1980-1990 and there is a trend of going up gradually in China.

ObjectiveTo evaluate the image quality of displaying the pulmonary artery and pulmonary emboli at different tube voltages and find the optimal tube voltage.MethodsSixty-six patients underwent contrast-enhanced dual energy CT pulmonary angiography (CTPA) from August 2007 to February 2010.Data obtained with 80 kVp,weighted average 120 kVp,and 140 kVp were divided into group Ⅰ,Ⅱ,and Ⅲ respectively.CT value of pulmonary artery ( grade 1—4),emboli,and muscles were measured.Corresponding signal to noise ratio (SNR) and contrast to noise ratio (CNR) were calculated.One-way ANOVA analysis and Friedman test were used to analyze statistical significance among these values.Image quality of CTPA from these three groups was assessed.The inter-reader agreement of image quality was performed by kappa test.ResultsCT value of branch 1 to 4 of ptlmonary artery was (446 ± 140) HU,(433±130) HU,(411 ±138) HU,and (392±127) HU in group Ⅰ,(303±91) HU,(290±85) HU,(276±86) HU,and (263 ±85) HU in group Ⅱ,and (244 ±70) HU,(230 ±63) HU,(216 ±72) HU,and (205 ±68) HU in group Ⅲ.There was significant difference for CT values (P ＜0.01) among three groups.CT value of pulmonary artery in 80 kVp images was higher than 140 kyp and 120 Kvp.On quantitative analysis of 37 patients,CNR value of pulmonary clots was 8.3 ± 3.3,8.0 ± 2.9,and 5.6 ± 2.2 in group Ⅰ,Ⅱ,and ⅢⅢ,respectively.CNR values of pulmonary clots in 80 kVp images and 120 kVp images were higher than that in 140 kVp (P ＜0.01 ).There was no statistical difference for image quality of CTPA among the three groups ( P ＞ 0.05 ).Agreement of image quality of CTPA derived from 80 kVp (kappa value =0.789,P ＜0.01 ) was superior to that of 120 kVp (kappa value =0.652,P ＜0.01 ) and 140 kVp ( kappa value = 0.509,P ＜ 0.01 ).Conclusions CT value of pulmonary artery in 80 kVp images was higher than that of weighted average 120 kVp and 140 kVp,and the image quality and CNR was comparable with that of weighted average 120 kVp images.This tube voltage ( 80 kVp) is optimal for CT pulmonary angiography in the evaluation of patients with suspected pulmonary embolism.

AIM: To investigate the effects of aging on the angiotensinⅡ receptors (ATR) in different parts of the kidney. METHODS: Expression of AT 1 receptor in renal cortex was determined by Western and Northern blotting. Five micrometer thick cryostat sections of 3 or 24-month Wistar rats were mounted onto a 1.35?m thin polyethylene membrane. Glomeruli, tubules and arteries of rat kidney were isolated by laser microdissection and pressure catapulting system, AT 1aR mRNA, AT 1bR mRNA AT 2R mRNA were measured with reverse-transcription PCR(RT-PCR). RESULTS: Western and Northern blotting showed that protein and gene expression of AT 1 receptor in kidney cortex decreased in 24 month Wistar rats compared to those in 3 month Wistar rats. Glomeruli, tubules and arteries were quickly isolated by laser microdissection and pressure catapulting system without contamination. Compared to young group, AT 1aR mRNA expression was decreased in the tubules of aged rats, no changes was found in isolated glomeruli. AT 1bR mRNA was decreased in glomeruli and tubules. Both AT 1aR mRNA, AT 1bR mRNA were increased in the arteries. AT 2R mRNA was only increased in the tubules, whereas there were no significant changes in the glomeruli or arteries. CONCLUSION: Angiotensin Ⅱ receptors are regulated selectively in different portions of aged kidney, which might play an important role in aging related changes of the kidney.

Objective To investigate MR imaging features of femoral marrow in treated ?-thalassemia major.Methods MR imaging of the proximal femoral marrow was performed in 35 cases of ?-thalassemia major and 45 age-and sex-matched normal children as control.Coronal images of femoral marrow with the techniques of spin echo and fast field echo(FFE)were obtained.On T_1-weighted imaging the red and yellow femoral marrow were judged and marrow distribution was classified into five groups.The hemosiderosis of marrow was judged on the basis of signal intensity of marrow on FFE imaging.The marrow distribution classification and the hemosiderosis on MR imaging were correlated with clinical features.Results On FFE,marrow hemosiderosis occurred in 15 patients with a marked hypo-intensity signal and was related to the age(P=0.032).On T_1-weighted imaging,the femoral marrow in 35 patients was classified as groupⅢand IV,while the marrow distribution was groupⅠorⅡin all normal children,there was statistically significant difference(P

The dynamic of endophytic bacteria at different growth stage of tomato and use of these endophytic bacteria to control tomato bacterial wilt were studied. The results showed that endophytic bacteria could be found in the tomato seeds and their quantities reached the highest peak in the adult plants both in resistant and susceptible cultivars. The amount of endophytic bacteria in adult plants of resistant tomato cultivars was 2.43?10~5CFU/g FW in the root and 22.9?10~4 CFU/g FW in the stem, while the amount of endophytic bacteria in adult plants of susceptible tomato cultivars was 9.8?10~4CFU/g FW in the root and 13.4?10~4CFU/g FW in the stem respectively. Seventeen strains of endophytic bacteria from resistant cultivars and only seven strains from susceptible cultivars were found to be antagonistic to Ralstonia solanacearum. In addition, some strains of endophytic bacteria had the abilities of promoting tomato seed germination and controlling tomato bacterial wilt, among which, strain 5R and 3R had better control effect of 91.7% and 81.3% respectively.

The population of bacterial physiological groups in tomato with different resistant to Ralstonia solanacearum was studied. The results suggested that endophytic bacterial communities and population in tomato variety changed with different resistant cultivars, different stages of tomato and seasons. It was con-ducted that the amount of ammoniation bacteria was the highest among the seven physiological bacterial groups. There were more ammoniation bacteria in high resistant tomato cultivars than that in high suscepti-ble cultivars. It may indicate that ammoniation bacteria played a key role in the occurrence of tomato bacte-rial wilt. In addition, the total amount of physiological bacteria in resistant cultivars was more than that in susceptible cultivars in different stages of tomato, and the tendency of changing displayed fluctuation. The average level of quantities of the ammoniation bacteria, nitrifiers bacteria, erobic nitogenfixing bacteria and desulphate reducer bacteria in summer were higher than that in winter, while the population of the sulphate reduced bacteria in winter was higher than that in summer. Furthermore, the amount of anaerobic bacteria was the least among them.

Objective To study the relationship between environmental chemical elements,vires infection and dilated cardiomyopathy(DCM).Methods In 2008,233 patients with DCM(case group)and 150 patient with stable angina(control group)were chosen in Liaocheng People's Hospital and Yanggu People's Hospital,Shandong province.Population distribution and disease history were surveyed in the two groups.Human myocardial antibody IgG(AMA-IgG),Coxsackie B virus IgG(CBV-IgG),Adenofirus antibody IgG(ADV-IgG)were detected by ELISA in both the case group and the control group.Serum trace elements were detected in the two groups.The general chemical and toxicological indicators in drinking water of the high-and the low-incidence aireas of the disease were control group[60.00%(90/150),χ2=13.80,P<0.01)].Per capita annual income(Yuan,RMB)in the case group (3207.82±618.51)was lower than that of the control group[(5086.61±886.12),t=24.40,P<0.01].Personal alcohol consumption in the case group[(175.00±160.50)g/d]was higher than that of the control group[(110.22±100.03)g/d,t=4.40,P<0.01)].The rate of myocarditis in the case group[5.15%(12/233)]was higher than ADV-IgG in the cage group were 7.78%(7/90),6.67%(6/90)and 6.67%(6/90),respectively.Compared with those in the control group[3.33%(2/60),5.00%(3/60)and 5.00%(3/60),χ2=1.26,0.18,0.18,all P>0.05],no mg/L]in drinking water of the high-incidence areas were significantly higher than that of iron[(0.39±0.67)mg/L,t=2.11,P<0.05]and that of manganese[(0.15±0.14)mg/L,t=3.01,P<0.01]in the low-incidence arefas.The content of semm iron[(69.1±57.8)μmol/L]in the case group evidently exceeded the normal range(15.6-35.9 μmol/L)and obviously higher than that in the control group[(20.0±17.5)μmol/L,t=5.04,P<0.01].Conclusions Theso data do not support that DCM is related with persistent virus infection and autoimmunization.DCM is probably related with low incomes,high alcohol consumption,myocarditis,high iron and manganese contents in drinking water and high content of serum iron.

Objective To investigate the feasibility of a novel molecular probe 99Tcm-3P4-RGD2 in evaluating arterial plaque stability after atorvastatin intervention in rabbits with SPECT/CT. Methods Eighteen male New Zealand rabbits were randomly divided into group A (stable plaque), group B (vulnerable plaque), and group C (vulnerable plaque with statin intervention). All rabbits were fed with high-fat food for 12 weeks. After high-fat feeding for two weeks, sham surgery was performed on group A. In the meantime, abdominal aorta injury was performed on group B and group C. After that, rabbits of group C were given oral atorvastatin (2.5 mg·kg-1·d-1). 99Tcm-3P4-RGD2 SPECT/CT imaging was performed on each group at the end of 4, 8 and 12 weeks. T/NT ratios were calculated. Animals were sacrificed at the end of 12 week after imaging studies. The abdominal aortas were collected, imaged with SPECT/CT, and evaluated by pathological HE staining and immunohistochemical analysis. MVD was calculated. Differences among 3 groups were analyzed using one-way analysis of variance. Results There was no significant radioactive uptake in the abdominal aortas of three groups on the 4th week′s imaging. The radioactive uptake in abdominal aortas increased slightly on the 8th week, with the highest radioactive uptake in group B. The radioactivity in abdominal aortas of the 3 groups maintained increasing on the 12th week, with T/NT ratios of 1.579±0.217, 1.873±0.226 and 1.524±0.237, respectively (F=8.984, P<0.05). In ex vivo abdominal aorta images, especially images of group B, radioactivity in lesion sites was higher than that in normal tissue. Accordingly, results of HE staining showed that artery plaques of group A and group C were grade Ⅱ and group B was grade Ⅳ. The MVD of group A, B and C was 8.17±1.17, 15.86±1.07 and 7.17±1.60, respectively (F=9036, P<0.05). Conclusion 99Tcm-3P4-RGD2 SPECT/CT imaging has a high sensitivity in the evaluation of arterial plaque stability after statin intervention in rabbits.