Objective To study the seasonal variation of indoor 222Rn and 220Rn concentrations in Longdong district,Gansu Province.Methods A total of 44 houses from 5 different types of raw soil architectures and 5 ordinary brick houses from a typical area were selected in Longdong district,Gansu Province in China.The LD-P discriminative 222Rn and 220Rn detectors were used to measure the indoor concentrations of 222Rn and 220Rn during four seasons in one year.Results The indoor concentrations of 222Rn showed a significant seasonal variation,which varied with different types of houses.222Rn concentrations of ordinary brick houses,soil brick houses and the cave dwellings were higher in winter and autumn and lower in summer.The average concentrations of 222Rn were 55.3-90.3 Bq/m3 in winter,36.4-65.7 Bq/m3 in spring,35.6-63.9 Bq/m3 in summer,and 60.7-87.2 Bq/m3 in autumn.For cave dwellings,open-cut cave dwellings and the underground cave dwellings,222Rn concentrations were higher in summer and autumn,and lower in winter and spring.The average concentrations of 222Rn ranged from 139-184 Bq/m3 in winter,135-199 Bq/m3 in spring,179-252 Bq/m3 in summer,172-242 Bq/m3 in autumn.The seasonal variation of indoor 220Rn was basically consistent in six types of houses,and lower in winter and spring and highest in autumn.The average concentrations of 220Rn ranged from 43.4-64.3 Bq/m3 in winter,60.6-537 Bq/m3 in spring,77.7-792 Bq/m3 in summer,63.2-1077 Bq/m3 in autumn.The indoor concentrations of 222Rn and 220Rn were different among different types of houses,and they were generally higher in type of raw soft architectures than in that of ordinary brick houses.Conclusions 222Rn concentrations indoors showed a significant seasonal variation and varied with different types of houses.

Objective To observe the effects of botulinum toxin A(BTX-A) injection combined with treadmill training on motor and gastrocnemius function in rats after spinal cord injury (SCI),so as to develop a possible treatment.Methods A total of 48 female Sprague-Dawley rats were randomly divided into four groups(n =12 in each):a control group which received normal saline injection(group Con-NS),an exercise group with normal saline injection(group Ex-NS),the other control group with BTX-A injection(group Con-BTX)and an exercise group which also received BTX-A injection(group Ex-BTX).All rats were subjected to incomplete SCI modelling using Allen's method.Each group then had l0 members left because of death or significant weight loss.After SCI modelling,BTX-A or normal saline were injected to rats' gastrocnemius,followed by weight support treadmill training(BWSTT) on days 7 through 35 days for the two exercise groups.Motor function was evaluated using inclined plane test before and 2 days,1,2,3,4 and 5 weeks after the injury.All rats were sacrificed 35 days after the surgery.Digit Abduction Scoring(DAS) and electrophysiological testing were performed prior to sacrifice,and the general form and the wet weight of gastrocnemius were observed after resection.Results No significant differences in the inclined plane angle among 4 groups were detected before injury and 2 days afterward (P ＞ 0.05).At the 2nd-Sth week,however,the inclined plane angles in group Ex-NS were significantly higher than those in group Con-NS (P ＜ 0.05).Those of group Ex-NS were also significantly higher than group Ex-BTX 2-5 weeks after injury (P ＜ 0.05).No significant differences were detected between group Con-BTX and group Ex-BTX,as well as group Con-NS and group Ex-BTX at each time point (P ＞ 0.05).And the average DAS score in group Con-BTX and group Ex-BTX was 0,while that of Con-NS group and group Ex-NS were both 4.There were no significant differences between the two normal saline injection groups (P ＜ 0.05),nor between the two BTX-A injection groups (P ＜ 0.05).However,the average DAS scores in the Con-BTX and Ex-BTX groups were significantly higher than the Con-NS and Ex-NS groups (P ＜ 0.05).No significant atrophy of gastrocnemius muscles were observed in the Con-NS group or Ex-NS group,and as would be expected,the muscles in group Ex-NS were thicker on average than those in group Con-NS.Significant atrophy was observed in group Con-BTX and group Ex-BTX.Moreover,the muscle wet weight was significantly higher in group ExNS than group Con-NS (P ＜ 0.05).Compared with group Con-NS and group Ex-NS,the muscle wet weight was significantly lower in group Con-BTX and group Ex-BTX (P ＜ 0.05).No significant differences in the latency of the compound muscle action potential (CAMP) were detected among 4 groups (P ＞0.05),but the CAMP amplitude was significantly less in the control groups than in the exercise groups.(P ＜0.05).Conclusions Exercise training can significantly improve motor and skeletal muscle function in SCI rats,but BTX-A injection can inhibit the improvement.

Objective To study the protein expression levels of matrix metalloproteinases (MMPs)and their inhibitors in bone tissues of rat femoral head and to explore the relationship between necrosis of femoral head and glucocorticoid.Methods Twenty healthy adult SD rats were randomly divided into glucocorticoid group and control group,with 10 rats in each.Glucocorticoid group was treated with intramuscular injection of hydrocortisone twice a week.The control group received normal saline of the same volume.Four weeks later,bone tissues of left femoral head were collected from each group of rats for HE determination of femoral head necrosis.The expressions of matrix metalloproteinase-1 (MMP-1 ), matrix metalloproteinase-2 (MMP-2 ), tissue inhibitor of matrix metalloproteinase-1 (TIMP-1 ),and tissue inhibitor of matrix metalloproteinase-2 (TIMP-2 )at mRNA and protein levels were detected by RT-PCR and Western blot techniques,respectively.Results The expressions of MMP-1 and MMP-2 at mRNA and protein levels were higher in glucocorticoid group than those in the control group. However,TIMP-1 and TIMP-2 gene and protein expression levels were lower in glucocorticoid group (all P<0.05). Conclusion The expressions of MMPs in bone tissues of rat femoral head in early necrosis were increased,but their inhibitors had decreased expressions. We can draw the conclusion that glucocorticoid-induced necrosis of femoral head may be related to its regulation of the expression levels of MMPs and their related inhibitors.

Objective To analyze the serological detection results of hemolytic disease of newborns(HDN)in neonatal hyperbil-irubinemia and to explore the relationship between serological results and related factors.Methods The neonatal hemolytic three i-tems test were performed on blood specimens of 796 cases of neonatal hyperbilirubinemia.The relationship between the positive rate of HDN with the related factors such as blood type,specimens collecting time,hemoglobin level and serum total bilirubin value was analyzed.Results Among 796 cases of hyperbilirubinemia,184 cases were HDN(23.12%),in which 796 cases were ABO-HDN and 8 cases were Rh-HDN.The direct free antibody test,antibody release test and direct antiglobulin test were positive in 180 cases (22.61%),184 cases(23.12%)and 140 cases(17.59%)respectively.The HDN positive rate of the newborns with B blood type was higher than that of the newborns with A blood type,the difference between them had statistical significance(χ2 = 10.304,P <0.05).The HDN positive rate was closely related with the specimen collection time,moreover,the greater the day age,the higher the HDN positive rate,the difference showing statistical significance(P <0.05).The hemoglobin level and serum total bilirubin val-ue had statistically significant difference between newborns with HDN and those without HDN(P <0.05).Conclusion The posi-tive rate of HDN is high in newborns with hyperbilirubinemia.The hemolytic three items test should be performed as early as possi-ble.Combining with the hemoglobin level and serum total bilirubin value can increase the HDN detection rate.

Objective To study the structure and function changes of erythrocyte in hypercholesterolemia rabbits that treated with irradiation in auricle root by low level 650 nm laser.Methods Sixteen male rabbits were selected to establish the model animal of hypercholesterolemia,successful model rabbits were divided into 2 groups (model and treatment groups),6 rabbits per group,and 6 normal rabbits were selected as control group.650 nm laser of 100 mW were given in auricle root in rabbits of treatment group for 16 weeks (6 d one week,twice a day,30 min one time).Blood from ear vein was collected every 4 weeks to perform routine and biochemical blood examination,and one-drop blood test under microscope was used for blood accumulation observation.Results Total number of red blood cells of treatment group decreased,while model group showed an increasing trend than normal group (P＜0.05).Hemoglobin in three groups were lower than other two groups (P＞0.05).Hematocrit (HCT) in treatment group were lower than that in normal group,while HCT in model group were higher than that in other two groups and showed a higher aggregation degree also.Less than model group,treatment group showed less aggregation degree but with higher total bilirubin.Conclusions Low level laser of 650 nm showed an effect on total number of erythrocytes,HCT and red blood cells aggregation,high dose of laser might be injury for erythrocytes and lead to total bilirubin increasement.

OBJECTIVE To investigate the beta-lactamase gene and intⅠ1 gene in ESBLs-producing Klebsiella pneumoniae.METHODS Beta-lactamase gene and intⅠ1 gene were analyzed by PCR.RESULTS The positive rates of TEM,SHV,OKP,CTX-M-1group,CTX-M-2group,CTX-M-9group,GES,PER,VEB,OXA-10,ACT-1,LEN,DHA,and intⅠ1 were 51.4%,0%,0%,17.1%,0%,11.4%,0%,0%,0%,0%,0%,5.7%,17.1%,and 60%,respectively.Beta-lactamase gene was found in 62.9%,intⅠ1 gene was found in 60%.CONCLUSIONS There are very high positive percentages of beta-lactamase gene and intⅠ1 gene in ESBLs-producing K.pneumoniae.

ObJective To evaluate the multi-slice spiral CT (MSCT) in the diagnosis of early small renal cell carcinoma (RCC). Methods 32 cases of small RCC proved by pathology were retrospectively analyzed. The relationship of imaging features MSCT with pathology was compared. Results Of the 32 RCC in this study, 19 patients were with low density, 6 medium density, and 5 minimal high density. In 24 patients, the lesion were seen as a mixed enhancement pattern, 8 were with the homogeneous enhancement pattern.In cortical phase, clear cell RCC (25/32) tended to be marked enhancement or mixed enhancement pattern; 2 chromophobe lesions and 2 angsarcomakoid renal cell carcinoma (2/32, 2/32 respectively) tended to enhance moderately, papillary lesions (3/32) were mostly hypovascular and homogeneous enhancement pattern. The detection and characterization as well as accuracy of staging in 32 small RCC on MSCT were 100%, 93.75%, and 84.38%, respectively. Conclusion Muhiphase enhanced MSCT scan was a reliable technique in the dectection and clinical predicting subtype of small RCC.

Objective To investigate the distribution and sequence conservation of Hap adhensin encoding gene (hap) in clinical isolates of nontypeable Haemophilus influenzae (NTHi), to screen out and identify the predominant T-and B-cell (T-B) combined antigenic epitopes on Hap protein and to analyze their immunogenicity.Methods Sequence conservation of hap genes in NTHi strains and T-B combined antigenic epitopes were predicted using bioinformatic softwares.PCR was used to amplify the 156 bp segment at 5′-end and the 855 bp segment at 3′-end of hap gene (hap-5′-156 and hap-3′-855) and the amplified products were sequenced.Phage display systems of seven T-B combined antigenic epitopes located on the 55 aa segment at N-terminal and the 285 aa segment at C-terminal of Hap protein (Hap-N52 and Hap-C285) were constructed.Western blot assay and ELISA were performed to detect the antigenicity and immunoreactivity of different T-B combined epitopes displayed by recombinant phage PⅢ protein (rPⅢ).Results Hap protein encoded by the hap gene in NTHi was located on membrane surface.Sequences of the 156 bp segment at 5′-end and the 855 bp segment at 3′-end of hap genes extracted from different NTHi strains were relatively conservative, but many mutations were found in sequences at the middle regions of these hap genes.All of the 56 NTHi strains carried hap-5′-156 and hap-3′-855 segments and shared 92.3％-100％ identities in nucleotide and amino acid sequences of these segements.Hap-N5-24 in the Hap-N52 segment as well as Hap-C4-27, Hap-C28-47, Hap-C114-129, Hap-C150-173, Hap-C200-227 and Hap-C241-267 in the Hap-C285 segment was predicted as the T-B combined antigenic epitope with a higher score and less mutations.Results of Western blot assay and ELISA confirmed that the rPⅢ-displayed Hap-C4-27 and Hap-C150-173 epitopes presented clear hybridization bands with NTHi antisera, and 96.9％ (63/65) and 92.3％ (60/65) of serum samples from children with NTHi infection were positive for antibodies against Hap-C4-27 and Hap-C150-173 epitopes, respectively.Conclusion The gene of hap is widely distributed in clinical isolates of NTHi.Moreover, sequences of the 156 pb segment at 5′-end and the 855 bp segment at 3′-end of hap gene are conservative.Hap-C4-27 and Hap-C150-173 are the predominant T-B combined antigenic epitopes on Hap protein, suggesting that they can be used as epitope candidates for developing multiple antigenic peptide vaccines against NTHi.

Objective To investigate the levels and distribution of radon concentrations in groundwater in some representative cities in China,and estimate the effective dose from inhaled radon released from domestic groundwater.Methods A total of 12 cities in 7 provinces (municipalities) were selected,including Beijing,Inner Mongolia,Ningxia,Shaanxi,Henan,Liaoning and Heilongjiang.In total,73 water samples from groundwater supply were taken.Radon concentrations in water samples were determined by using a continuous radon monitor with air-water exchanger.Results The average radon content in groundwater for drinking was 11.8 Bq/L in 12 cities in 7 provinces,ranging from 1.0 to 63.8 Bq/L.The radon concentrations in 37％ water samples exceeded 1 1.1 Bq/L,the safe limit recommended for drinking water by the United States Environmental Protection Agency (EPA).The radon contents in all of the water samples was lower than the reference level 100 Bq/L recommended by World Health Organization (WHO).The average annual effective dose arising from inhaled radon released from groundwater was 29 μSv (2.4 to 160 μSv).Conclusions Generally,the effective dose from inhaled radon released from groundwater is negligibly low.However,in some areas dominated by granite bedrock,the dose contribution from radon released from groundwater to residents should be routinely monitored.

Objective To guarantee the quality of measurenents with the radon-thoron discriminative detectors of our laboratory.Methods LD-P radon-thoron discriminative detector participated in the international intercomparison for integrating radon/thoron detectors organized by National Institute of Radiological Science (NIRS,Japan).Detectors were sent to NIRS for exposure.Radon intercomparison was conducted with radon chamber providing three levels of exposure:low,medium and high levels.Thoron intercomparison was carried out at thoron chamber,which also provided three levels of exposure:low,medium and high levels.Detectors were posted back to our laboratory for etching and analysis after exposure.Then the measured values were submitted to NIRS.Finally the reference values were informed of us.Results The relative percent difference (RPD) between the measured value and the reference value for radon was-13.8％,-14.4％ and-17.1％ at low,medium and high levels respectively,and that of thoron were-14.4％,8.9％ and-3.2％ at three levels respectively.Conclusions Both radon and thoron measurement of our detectors rank asCategory Ⅰ in the 4th international intercomparisons for integrating radon/thoron detectors with the NIRS radon/thoron chambers.