OBJECTIVE: The purpose of this study is to estimate a patient's organ dose (effective dose) during performance of dual X-ray absorptiometry by using the correlations derived from the surface dose and the depth doses in an anthropomorphic phantom. MATERIALS AND METHODS: An anthropomorphic phantom was designed and TLDs (Thermoluminescent Dosimeters) were placed at the surface and these were also inserted at different depths of the thyroid and uterus of the anthropomorphic phantom. The absorbed doses were measured on the phantom for the spine and femur scan modes. The correlation coefficients and regression functions between the absorbed surface dose and the depth dose were determined. The derived correlation was then applied for 40 women patients to estimate the depth doses to the thyroid and uterus. RESULTS: There was a correlation between the surface dose and depth dose of the thyroid and uterus in both scan modes. For the women's dosimetry, the average surface doses of the thyroid and uterus were 1.88 (micro)Gy and 1.81 (micro)Gy, respectively. Also, the scan center dose in the women was 5.70 (micro)Gy. There was correlation between the thyroid and uterus surface doses, and the scan center dose. CONCLUSION: We concluded that the effective dose to the patient's critical organs during dual X-ray absorptiometry can be estimated by the correlation derived from phantom dosimetry.
*Absorptiometry, Photon ; Female ; Femur/radiography ; Humans ; Linear Models ; Middle Aged ; *Models, Anatomic ; *Phantoms, Imaging ; *Radiation Dosage ; Spine/radiography ; Thyroid Gland/*radiation effects ; Uterus/*radiation effects

Over one-third of the world’s population are seropositive for Toxoplasma gondii. One of the important traits of T. gondii is its ability to alter and manipulating the behavior and personality of its intermediate host. The current study was aimed to determine the prevalence of acute and chronic toxoplasmosis in those persons suffer from schizophrenia using serological and molecular techniques. In this cross-sectional study, blood samples were taken from 118 Schizophrenia patients hospitalized in Sistan and Baluchestan province, southeast of Iran. IgM and IgG anti-Toxoplasma antibodies were measured using enzyme-linked immunosorbent assay (ELISA). Furthermore, the presence of parasite was evaluated using nested-PCR B1 gene. Among 118 schizophrenic patients, 48 (40.67%), 4 (3.37%) and 14 (11.86%) were tested seropositive only for IgG, only for IgM and for both of IgG/IgM. So that, total prevalence was 66/118 (55.91%). All samples were also examined using nested-PCR and T. gondii DNA was found in 41 (34.74%) samples. Our study showed high seroprevalence of toxoplasmosis in southeast of Iran.