• Radiation Oncology Journal
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• v.20 no.4
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• pp.396-404
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• 2002

Purpose : Many papers support a correlation between rectal complications and rectal doses in uterine cervical cancer patients treated with radical radiotherapy. In vivo dosimetry in the rectum following the ICRU report 38 contributes to the quality assurance in HDR brachytherapy, especially in minimizing side effects. This study compares the rectal doses calculated in the radiation treatment planning system to that measured with a silicon diode the in vivo dosimetry system. Methods : Nine patients, with a uterine cervical carcinoma, treated with Iridium-192 high dose rate brachytherapy between June 2001 and Feb. 2002, were retrospectively analysed. Six to eight-fractions of high dose rate (HDR)-intracavitary radiotherapy (ICR) were delivered two times per week, with a total dose of $28\~32\;Gy$ to point A. In 44 applications, to the 9 patients, the measured rectal doses were analyzed and compared with the calculated rectal doses using the radiation treatment planning system. Using graphic approximation methods, in conjunction with localization radiographs, the expected dose values at the detector points of an intrarectal semiconductor dosimeter, were calculated. Results : There were significant differences between the calculated rectal doses, based on the simulation radiographs, and the calculated rectal doses, based on the radiographs in each fraction of the HDR ICR. Also, there were significant differences between the calculated and measured rectal doses based on the in-vivo diode dosimetry system. The rectal reference point on the anteroposterior line drawn through the lower end of the uterine sources, according to ICRU 38 report, received the maximum rectal doses in only 2 out of the nine patients $(22.2\%)$. Conclusion : In HDR ICR planning for conical cancer, optimization of the dose to the rectum by the computer-assisted planning system, using radiographs in simulation, is improper. This study showed that in vivo rectal dosimetry, using a diode detector during the HDR ICR, could have a useful role in quality control for HDR brachytherapy in cervical carcinomas. The importance of individual dosimeters for each HDR ICR is clear. In some departments that do not have the in vivo dosimetry system, the radiation oncologist has to find, from lateral fluoroscopic findings, the location of the rectal marker before each fractionated HDR brachytherapy, which is a necessary and important step of HDR brachytherapy for cervical cancer.

• Journal of Radiation Protection and Research
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• v.37 no.4
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• pp.213-218
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• 2012

Alpha spectrometry has been typically used for determination of the uranium isotopes in soil. For a number of uranium analysis in soil samples, rapid sample digestion with limited quantities of mixed acid containing HF will give a contribution for effective management of uranium analysis. Microwave digestion system is evaluated for rapid sample digestion using reference uranium soil (IAEA-375 soil). For completion of 0.5 g of soil digestion by microwave, 3 ml of HF in a 10 ml of mixed acid is minimum requirement volume for completed soil digestion for 80 minutes. Microwave digestion is timely effective techniques for uranium measurement using alpha spectrometry compared to the other methods (open vessel digestion, closed vessel digestion) due to rapid sample digestion. In addition, it can be reduced the occurrence of hazardous substances by minimizing the amount of HF.

• Biomedical Science Letters
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• v.1 no.1
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• pp.1-8
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• 1995

The present study was undertaken to determine the dissociation constant (Kd)of monoclonal antibody to human apolipoprotein A-I (apo A-I) using enzyme-linked immunosorbent assay (ELISA). First the monoclonal antibody was incubated in solution with the antigen until the equilibrium was reached; then the free antibody which remains unsaturated at equilibrium was captured by binding to antigen on the microtiter plate and be measured by a classical indirect ELISA. The value of Kd determined from Scatchard plot was 0.625$\times$10^{-9}$ for purified antibody and 0.720$\times$10$^{-9}$ for unpurified antibody. This method was valuable for the measurement of true dissociation constant and found to be simple, reproducible, and accurate.

• Progress in Medical Physics
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• v.2 no.2
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• pp.129-139
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• 1991

The method of etching tracks in PN-3 dosimeter has been applied to tracks of recoil protons from a neutron source. Both the etch and the detection response of PN-3 has been studied as a function of etched-track diameters against various parameters. We could obtain very useful informations about charge, energy, and mass of particles and the relationship between the track etching rate and the track forming procedure in order to analyze the particle recorded in the solid state track detector. The best etching condition could be found by means of changing the etching circumstances for various energies and particles in order to detect the charged particle accurately. It could be influenced widely that the polymer plastic detector could develep the detecting technique for the low energy level neutron and could be used as a neutron dosimeter in the radiation field such as the nuclear power station, the medical institute and the nondtructive testing institute.

• Korean Journal of Animal Reproduction
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• v.18 no.2
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• pp.95-99
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• 1994

The purpose of the present study was to determine the in vivo effect of oxytocin antagonist-I(Al) on uterine oxytocin receptor number (Rn) and/or binding affinity (Kd) in the estrous rat. Anesthetized rats were given a bolus infusion of control or 5${\mu}\textrm{g}$ of AI and sacri-ficed 0.5 and 4 hours later. The uterine tissue was removed, trimmed and frozen. Membrane oxytocin receptors were isolated after homogenization of uterine tissue and differential ultracentrifugation. The oxytocin receptor assay was performed by saturation with cold oxytocin competion with a high specific activity oxytocin antagonist. Rn and Kds were determined by nonlinear curve fitting methods. No differences(p>0.05) between the AI and control treated animals in either oxytocin receptor number or binding affinity was detected in this study. These data suggest that the major mode of action of AI is via competitive inhibition at the uterine oxytocin receptor and not by altering receptor number or binding affinity.

• Progress in Medical Physics
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• v.19 no.1
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• pp.1-8
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• 2008

Technisium $(^{99m}Tc)$ is one of the most widely used radioactive isotopes for diagnosis in nuclear medicine. In general, technisium is produced inside the so called $^{99m}Tc$ generator which is usually made out of lead to shield relatively high energy radiation from $^{99}Mo$ and its daughter nuclide $^{99m}Tc$. In this paper, a GEANT4 simulation is carried out to test the safety of the $^{99m}Tc$ generator, taking the Daiichi product with radioactivity of 500 mCi as an example. According to the domestic regulation on radiation safety, the dose at 10 cm and 100 cm away from the surface of shielding container should not exceed 2.0 mSv/h and 0.02 mSv/h, respectively. The simulated dose turned out to be less than the limit, satisfying the domestic regulation.

• Journal of the Korean Society for Nondestructive Testing
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• v.28 no.1
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• pp.25-32
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• 2008

[ $^{169}Yb$ ] industrial NDT sealed sources were developed by using $Yb_2O_3$ pellets as the target and demonstrated for their performance. To produce the pellets, optimal compacting and sintering conditions were determined experimentally. Source holders for $^{169}Yb$ were designed and fabricated. After assembling an active source produced from HANARO with the developed source holder, a demonstration experiment was performed to compare the quality of the radiographs from $^{192}Ir$ and soft X-rays. This demonstration study showed that the developed $^{169}Yb$ produced better radiographs than $^{192}Ir$ for a carbon steel with less than a 4 mm thickness.

• Childhood Kidney Diseases
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• v.12 no.2
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• pp.262-266
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• 2008

Crossed renal ectopia is a congenital malformation in which both kidneys lie on the same side of the spine, usually side by side longitudinally. More often on the right side. Fusion of the two renal units is eight times more common than nonfusion. Although crossed renal ectopia is uncommon, this unusual entity must be considered in an infant when cystic mass in the abdomen or pelvis paticularly if no kidney can be found on the opposite side. In many cases of crossed fused ectopia with multicystic dysplastic kidney(MCDK), the diagnosis can be strongly suspected from the sonogram, and no other studies may be necessary. However, both intravenous urography and isotope renography is useful to assess the function of the crossed kidney. Crossed renal ectopia and MCDKs are associated with a greater incidence of ureteropelvic junction obstruction and reflux. So, screening voiding cystourethrography should be performed. Very few studies of MCDK in the setting of crossed fused ectopia have been reported. We have experienced a 3-year-old boy with crossed fused renal ectopia with multicystic dysplasia.

• Korean Journal of Head & Neck Oncology
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• v.13 no.2
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• pp.200-205
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• 1997

Background: There is considerable controversy concerning the most appropriate surgical treatment of patients with DTC. Objectives: In order to selection of the appropriate surgical treatment for DTC, we have analyzed the outcome of the different types of surgical treatment in low and high risk groups of DTC. Materials and Methods: From January 1968 through december 1980, a total of 71 patients with DTC were treated surgically at our institution. According to Cady and Rossi's scoring system, the patients were divided into low risk and high risk groups. Results: Seventy percent of patients were defined as low risk group with a 4% death rate whereas 30% of patients at high risk with a death caused by thyroid cancer in 38%(p<0.05). There was no difference in mortality between ipsilateral lobectomy and total thyroidectomy in both low and high risk groups(p>0.1). Conclusion: In our study, total thyroidectomy was not benefit in high risk group. These results suggested that total thyroidectomy must be selected carefully and based on clear evidence of major improvement in outcome or absence of other suitable surgical approaches. However, follow up study of more cases will be needed for accurate determination of the efficacy of total thyroidectomy in high risk group.

• The Journal of Natural Sciences
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• v.14 no.1
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• pp.39-50
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• 2004

T7 RNA polymerase is a single subunit RNA polymerase able to accomplish whole transcription process without auxiliary factors. In order to study transcription elongation mechanism of phage T7 RNA polymerse, stepwise walking of RNA polymerase was established by immobilizing biotinylated DNA template with streptavidin bead, series of active and stable elongation complexes were obtained, Transcripts were radio isotope labeled at the 16thm 17th and 18th nucleotide residues so stable elongation transcription complex of T7 RNA polymerase containing 22-40 nucleotide residues could be identified. We identified the positions of stablely formed transcription elongation complexes of termination site in intrinsic hairpin-independent PTH terminator sequence through the established stepwise walking of wild-type of mutant R173C T7 RNA polymerases. The results suggest that stable elongation transcription complexes were at the site of passing PTH terminator signal by mutant R173C RNA polymerase.