With the rapid development of radiological diagnosis and treatment technology, the construction of radiation diagnosis and treatment machine room and radiation safety management have become an important part of the daily management of hospitals. Due to the large number of laws and regulations involved, some hospitals still have problems such as imperfect construction of management systems, and insufficient professional competence of personnel, which leads to a lack of experience in the construction of radiation diagnosis and treatment room and radiation safety management in hospitals. This paper analyzed the practical experience of construction of radiological diagnosis and treatment machine room and radiation safety management. This paper analyzed the experience in constructing protective facilities for radiation diagnosis and treatment rooms in a medical institution, and provides the basis and reference for relevant units in room construction and radiation safety management.

With the rapid development of radiological diagnosis and treatment technology, the construction of radiation diagnosis and treatment machine room and radiation safety management have become an important part of the daily management of hospitals. Due to the large number of laws and regulations involved, some hospitals still have problems such as imperfect construction of management systems, and insufficient professional competence of personnel, which leads to a lack of experience in the construction of radiation diagnosis and treatment room and radiation safety management in hospitals. This paper analyzed the practical experience of construction of radiological diagnosis and treatment machine room and radiation safety management. This paper analyzed the experience in constructing protective facilities for radiation diagnosis and treatment rooms in a medical institution, and provides the basis and reference for relevant units in room construction and radiation safety management.

Objective:To study the application value of vacuum drainage technology in radioactive wastewater discharge system of hospitals, and provide theoretical basis and reference for relevant institutes to design or renovate their radioactive wastewater discharge systems.Methods:Based on the composition of vacuum drainage system and gravity drainage system, the differences in water consumption and other factors of different systems were theoretically evaluated. To take the radioactive wastewater discharge system in a hospital as a research example, the storable periods of the fixed decay pool were calculated by using the two different drainage techniques.Results:Compared with the traditional gravity drainage technology, the vacuum drainage technology could save a lot of water and significantly reduce wastewater discharge. The water consumption was 16% of that of ordinary toilets with gravity drainage. By using the vacuum drainage technology to reform the radioactive wastewater discharge system of the hospital under the same amount of diagnosis and treatment workload, the storable period of radioactive wastewater could be extended by nearly three times, from 92.5 d before the renovation to 297 d after the renovation, without increasing the capacity of the decay pool. After the transformation, the total activity and volumetric activity concentration of 131I when discharging wastewater from each decay tank could be reduced to 4 096 Bq and 0.17 Bq/L, respectively, and the volumetric activity concentration was much lower than the national emission requirements. Conclusions:Vacuum drainage can significantly reduce wastewater production, and is worth promoting and applying in nuclear medicine departments.

Objective:To study the application value of vacuum drainage technology in radioactive wastewater discharge system of hospitals, and provide theoretical basis and reference for relevant institutes to design or renovate their radioactive wastewater discharge systems.Methods:Based on the composition of vacuum drainage system and gravity drainage system, the differences in water consumption and other factors of different systems were theoretically evaluated. To take the radioactive wastewater discharge system in a hospital as a research example, the storable periods of the fixed decay pool were calculated by using the two different drainage techniques.Results:Compared with the traditional gravity drainage technology, the vacuum drainage technology could save a lot of water and significantly reduce wastewater discharge. The water consumption was 16% of that of ordinary toilets with gravity drainage. By using the vacuum drainage technology to reform the radioactive wastewater discharge system of the hospital under the same amount of diagnosis and treatment workload, the storable period of radioactive wastewater could be extended by nearly three times, from 92.5 d before the renovation to 297 d after the renovation, without increasing the capacity of the decay pool. After the transformation, the total activity and volumetric activity concentration of 131I when discharging wastewater from each decay tank could be reduced to 4 096 Bq and 0.17 Bq/L, respectively, and the volumetric activity concentration was much lower than the national emission requirements. Conclusions:Vacuum drainage can significantly reduce wastewater production, and is worth promoting and applying in nuclear medicine departments.

OBJECTIVETo investigate the prevalence of occult HBV infection in the normal population in Xiamen.

METHODS4 437 registered permanent residents, aged 1-59 years old, were selected in Xiamen using stratified random sampling method from September to October in 2006. Serum samples were obtained, the basic characteristics, inoculation of HBV vaccine, and liver disease were surveyed. The serum samples were tested five HBV seroimmunological markers. The HBsAg-negative specimens were subjected to HBV-DNA detection by nested PCR targeting for multiple gene segments. The amplified products were sequenced and the sequence was used for determination of HBV genotype and mutation analysis of amino acids located in HBsAg "a" epitope. Subjects with serum detectable HBV-DNA and negative result of HBsAg were considered as occult HBV infection.

RESULTSAmong the 4 437 subjects, 482 individuals were observed HBsAg positive and 3 944 were observed negative. Of the 3 955 HBsAg- negative specimens, 27 occult HBV infections were determined with the positive rate of 0.68% (27/3 955). There were 16 samples with genotype B and 11 with genotype C. 3 types of amino acid (AA) mutation (M133T, T140I, G145R) that influence "a" epitope conformation were observed in 9 subjects with occult HBV infection. S region was successfully sequenced in 312 of the 482 HBsAg positive samples. In subjects with occult HBV infection, the infection rate of genotype C HBV (40.74%, 11/27), inoculation rate of HBV vaccine (62.96%, 17/27), positive rate of HBsAb (51.85%, 14/27), and mutation rate of critical amino acid of "a" epitope (33.33%, 9/27) were higher than HBsAg positive individuals (22.76% (71/312), 13.78% (43/312),0.32% (1/312),0.99% (31/312), respectively), and all the difference were significant (χ(2) = 4.29, 41.26, 156.00, 13.07, respectively, and P value = 0.038, <0.001, <0.001, <0.001, respectively). While the average age in subjects with occult HBV infection (18.3 ± 16.2) were lower than that in HBsAg positive infection (34.4 ± 11.6), and the difference was significant (t = 6.67, P < 0.001). The reactive rate of HBeAb (11.11%, 3/27) and HBcAb (62.96%, 17/27) in subjects with occult HBV infection were lower than that in HBsAg positive infection (74.36% (232/312), 98.40% (307/312)), and the difference were significant (χ(2) = 46.74, 73.78, respectively, and P value <0.001, <0.001, respectively).

CONCLUSIONIn normal population in Xiamen, the infection rate of genotype C, the positive rate of HBsAb, the HBV vaccination rate, and the key AA mutation rate in "a" epitope are significantly higher in occult HBV infection than in HBsAg positive infection, and the age, the positive rate of HBeAb and HBcAb are significantly lower.

Adolescent ; Adult ; Child ; Child, Preschool ; DNA Mutational Analysis ; Genotype ; Hepatitis B ; diagnosis ; Hepatitis B Antibodies ; Hepatitis B Surface Antigens ; Hepatitis B Vaccines ; Hepatitis B virus ; Humans ; Infant ; Middle Aged ; Mutation ; Prevalence ; Vaccination

Objective To evaluate the role of dynamic contrast-enhanced magnetic resonance imaging (MRI) in the diagnose of prostatic cancer and benign prostatic hyperplasia (BPH), and to determine the correlation between dynamic MRI findings with angiogenesis.Methods Thirty-two cases of prostatic cancer and 40 cases of BPH underwent dynamic contrast-enhanced MRI.All the patients in this study were diagnosed by histopathology.The results of dynamic contrast-enhanced MRI were evaluated by early-phase enhancement parameters and time-signal intensity curves (SI-T curves), and the curves were classified according to their shapes as type Ⅰ, which had steady enhancement; type Ⅱ, plateau of signal intensity; and type Ⅲ, washout of signal intensity.The pathologic specimens of region of interest (ROI) were obtained, and HE staining, immunohistochemical vascular endothelial growth factor (VEGF), and microvessel density (MVD) measurements were performed.The relationships among dynamic contrast-enhanced MRI features, VEGF, and MVD expression were analyzed.Results In the early-phase enhancement parameters of dynamic contrast-enhanced MRI, onset time,maximum signal intensity, and early-phase enhancement rate differed between prostatic cancer and BPH(P