Abstract: Objective　In order to understand the radon exposure level of homes in Chongqing, this survey was carried out on the indoor radon concentration in 38 districts and counties of Chongqing. Methods　According to the population ratio of every 100 000 people, one monitoring site was arranged, and the number of parallel samples was 10% of the distribution sites. The monitoring sites covered 38 districts and counties in Chongqing. A total of 1 019 residential monitoring sites in 38 districts and counties in Chongqing were measured with radon accumulation detectors from July 2020 to June 2021. Results　The five districts/counties in Chongqing having the highest average concentration of residential radon in the year were Xiushan County 78.8 Bq/m3, Qianjiang District 78.0 Bq/m3, Yubei District 73.9 Bq/m3, Youyang County 71.4 Bq/m3 and Shapingba District 69.8 Bq/m3. The five districts/counties with the lowest mean concentration of indoor radon were 37.6 Bq/m3 in Zhongxian County, 36.4 Bq/m3 in Changshou District, 33.7 Bq/m3 in Kaizhou District, 33.2 Bq/m3 in Liangping District and 27.3 Bq/m3 in Wushan County. The concentration levels of radon in four seasons were 46.0 Bq/m3, 53.4 Bq/m3, 45.1 Bq/m3 and 59.5 Bq/m3, respectively. The concentration of radon was higher in Summer and Winter, and lower in Spring and Autumn, and the difference of concentration among four seasons was statistically significant (P<0.001). The radon concentration of newly built buildings after 2017 was relatively high, up to 61.8 Bq /m3, but there was no statistical significance in radon concentration in different building ages (P>0.05). The concentration of radon in rooms of buildings with less than 10 floors was higher, up to 63.2 Bq /m3, and there were significant differences in radon concentration among rooms of different floors (P<0.05). The average annual radon concentration in houses in Chongqing was about (51.6±19.5) Bq/m3, and the average annual effective dose of inhaling radon and its progeny by house-related people was about (1.38±0.52) mSv. Conclusion　The average annual radon concentration level of houses in Chongqing is within the standard limit value recommended by China, but the prevention and control of radon should be strengthened.

In this paper, we expatiate the advance of Tricholoma matsutake including distributing, environment, pure culture, domesticating cultivation and artificial forcing breeding in the area of Changbai Mountain of China.

Adenocarcinoma ; pathology ; Adenocarcinoma, Papillary ; pathology ; Aged, 80 and over ; Carcinoma, Renal Cell ; pathology ; Duodenal Neoplasms ; pathology ; Humans ; Kidney Neoplasms ; pathology ; Lung Neoplasms ; pathology ; Male ; Neoplasms, Multiple Primary ; pathology ; Sarcoma ; pathology ; Stomach Neoplasms ; pathology

OBJECTIVE To define the regularity of survival ability of HIV in natural environment,and prevent(infection) through contacting with positive body fluids during daily life or medical work.METHODS Having been diluted by sterile water or 10% serum RPMI 1640 medium,HIV was exposed to 4℃,room temperature(20-26℃) or 37℃ for different period of time.TCID_(50) of these samples was detected.Non-pathological samples were blind passaged for three generations.RESULTS HIV infective ability persisted more than 35 days both in(water) and medium at 4℃;whereas it persisted 7-14 days in water,14-21 days in medium at room temperature and 37℃.CONCLUSIONS HIV has higher resistance in natural environment.To prevent accidental spreading of HIV,HIV positive liquids and contaminants staffs should be treated carefully.

Comparative analysis of characteristic of species and esterase-isoenzyme of isolates of Polyporus umbel-latus from different regions were processed. The results indicated that isolates of Jizhaoling ( Z) and Zhushiling (ZJ) have significant differences in characteristic, and enzymatic band types of the two species also have significant differences. The homology at genetics between the two isolates is 0% , and consanguinity between the two i-solates is the farthest.

Agricultural Microbiology is a professional foundation curriculum for biology,botany and envi-ronmental majors in agricultural universities.After 1999,with the increase enrollment of the national under-graduate education and rapid construction of the university,the number of majors and students increased rapidly and quality of students and talent demand of society changed dramatically.Under such condition,in order to meet the society demand of microbiology,according to the distinguishing feature of different major groups,based on strengthening the basis teaching and stretching application teaching,new curriculum teaching model and method were explored positively,and then new curriculum system was constructed.Be-ing aroused sufficiently of the students’ subjective initiative,both the teaching quality and comprehensive quality were improved.

Objective To evaluate the biocompatibility of vessel extracellular matrix (VECM) with bladder smooth muscle cells of rabbits,and to discuss the feasibility of vessel extracellular matrix as a matrix for urinary tract reconstruction.Methods Primary cuhured bladder smooth muscle cells (RBSMCs) iso- lated from New Zealand rabbits were implanted on VECM (1?10~6 cells/ml).The effect of VECM on meta- bolic activity,attachment,proliferation of RBSMCs were monitored in vitro by inverted light microscopy and scanning electron microscopy.The extracts of VECM and emulsion were prepared as experimental group and positive controls separately.The culture medium was used as negative control,and simple culture medium without cells was used as blank control.The cell viability was monitored by MTT method after 1-,3-,5-d see- ding.The in vivo tissue response to VECM was investigated by implanting into the subcutaneous sites of the rabbits.Results VECM exhibited nontoxic and bioactive effect on RBSMCs.RBSMCs could be attached to and proliferated on VECM and remained their morphologies.The cell proliferation rates of experimental group were 95.61%、98.34%、102.91%,respectively,after 1,3,5 d;those of negative control group were 100.00% ,respectively;and those of positive control group were 35.14%、38.95%、32.66%,respectively. There was significant difference in the rate between experimental group and positive control (P＜0.01),and no significant difference in the rate between experimental group and negative control (P＞0.05).In vivo, VECM demonstrated favorable tissue compatibility without tissue necrosis and fibrosis.Conclusions VECM exhibits nontoxic and bioactive effects on primary cultured bladder smooth muscle cells.It is a suit- able material for urinary tract reconstruction.

Objective To investigation the pathological characteristics of esophageal squamous cell carcinoma to provide reference criteria for delineating the target area in radiotherapy.Methods Fifty-two patients from the Fourth Hospital of HeBei Medical University underwent resection whom all had been proved to have esophageal squamous cell carcinoma before operation.Chest CT was scanned and transmitted to the 3- dimensional conformal planning system for radiotherapy by VRX-16 scanner.The lesion of esophageal carcinoma was delineated in the 3-dimensional rebuild CT image and the lesion volume was computed by digital rebuild program.Every surgically resected specimen was made into pathologic giant section.The actual size of the specimen was obtained by calculating the size under the microscope with the shrinkage ratio.Multicentric carcinomatous lesion,severe dysplasia and direct intramural infiltration were observed in the giant section with a microscope and the order of such pathological characteristics were analysed statistically.Results 1.The tumor length by different method of preparation of operated specimens differed obviously.The longest was shown by CT. 2.Multicentric carcinomatous lesion was found in 15(29%)cases out of 52 patients.Proximal to the tumor,the mean distance between the multicentric carcinomatous lesion and the main lesion plus the length of the multicentric carcinomatous lesion was 3.02?1.45cm.Distal to the tumor,it was 2.60?2.44 cm.Severe dysplasia was found in 28 patients.Proximally,the mean distance between the severe dysplasia and the main lesion plus the length of the severe dysplasia was 2.45?1.30 cm.Distal to the tumor,it was 3.24?2.19 cm.Direct intramural infiltration was found in 41 patients,of which the mean length being 2.80?1.52 cm proximally and 2.02?1.51 cm distally. 3.Tumor thrombus was found in 6 patients and lymphoduct infiltration in 36 patients.Direct intramural infiltration was found at higher incidence in specimens complicated with lymphoduct infiltration(86%)and those complicated with tumor thrombus(91%).There were no apparent factors affecting severe dysplasia.The proximal distance to direct intra- mural infiltration was much longer than distally.Conclusions Multicentric carcinomatous lesion,severe dysplasia and direct intramural infiltration may be observed in esophageal squamous cell carcinoma.Multicentric carcinomatous lesion and direct intramural infiltration are obviously correlated with lymphoduct infiltration.To cover 95% of the microscopic extension,a margin of 5.0 cm is needed proximal to the base of gross tumor volume,and 7.5 cm distal to it.To cover 90% of the microscopic extension,a margin of 4.5 cm is needed proximally,and 5.0 cm distally.

Objective To evaluate the diagnostic value of fluorescent quantitative polymerase chain reaction(PCR) for Mycoplasma pneumoniae (MP) in children with MP pneumonia(MPP).Methods From Jun.2008 to Jan.2009,153 cases hospitalized with pneumonia were enrolled,and 30 cases without respiratory infection were enrolled as control group.Their respiratory secretion (including nasopharyngeal secretion,sputum,bronchialalveolar lavage fluid or pharyngeal swab) samples were collected for fluorescent quantitative PCR for MP.And their single or paired serums were collected for specific MP antibody detection.Results There were 123 cases confirmed with MPP by serology,among whom 114 cases were MP PCR positive.The quantitation of MP DNA was among 1.20?106-3.66?1010 gene copys/L. There were 30 cases with pneumonia negative with MP by the paired serum serology,among whom 2 cases were MP PCR positive,and the quantitation of MP DNA was (1.08-3.02)?107gene copys/L.All cases of control group were MP PCR negative.During the first and second weeks of the MPP onset,the sensitivity of MP-IgM from the first single blood samples were 66.7% and 83.9%,respectively.While the sensitivity and specificity of MP PCR were 92.7% and 93.3%,respectively.From the third week of the disease onset,the sensitivity of MP-IgM from the first single blood samples increased to 90.9%-100%.The clinical manifestations of MPP were nonspecific.Conclusions PCR is superior to serology for early diagnosis on MP infection.Combination of the 2 methods may be helpful to early and accurate diagnosis on MP infection.

Objective To study the postmortem distribution of Bromadiolone and its metabolite-Benzylideneacetone in dogs and provide an experimental evidence for the sampling of Bromadiolone poisoning cases. Methods The dogs were given 2LD50 and 4LD50 Bromadiolone by intragastric administration. Anatomy was conducted immediately after death and samples of body fluids and viscera (heart blood; peripheral blood, bile, urine, heart, liver, spleen, lung, kidney, brain, urinary bladder, left leg muscle, stomach, stomach contents, pancreas) were collected and detected after the dogs poisoning death. The Bromadiolon and its metabolite-Benzylideneacetone contents in samples were analyzed by GC/MS. Results Hemorrhagic symptoms came out at 3d after Bromadiolone delivery and deaths occurred at (178.40±20.94)h after intoxication. The postmortem distribution of Bromadiolon and its metabolite-Benzylideneacetone in dogs was as following: 2LD50 Bromadiolon: bile>urine, liver, heart, kidney>heart blood, peripheral blood, spleen, lung and so on. Benzylideneacetone: the content in bile, urine, heart blood, peripheral blood, lung, stomach contents are higher. 4LD50 Bromadiolon: bile, urine>liver, peripheral blood>heart blood, stomach contents and others. Benzylideneacetone:contents in bile, urine and lung are higher. Conclusion The postmortem distribution of Bromadiolon and its metabolite-Benzylideneacetone in dogs is uneven, contents in bile, urine, liver, heart blood and peripheral blood are higher, whichare suggested for forensic toxicological analysis in Bromadiolon poisonig case.