• Nuclear Engineering and Technology
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• 제55권1호
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• pp.215-221
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• 2023

Proton treatment may deliver a larger dose to a patient's skin than traditional photon therapy, especially when a range shifter (RS) is inserted in the beam path. This study investigated the effects of an RS on skin dose while considering RS with different thicknesses, airgaps and materials. First, the physical model of the scanning nozzle with RS was established in the TOol for PArticle Simulation (TOPAS) code, and the effects of the RS on the skin dose were studied. Second, the variations in the skin dose and isocenter beam size were examined by reducing the air gap. Finally, the effects of different RS materials, such as polymethylmethacrylate (PMMA), Lexan, polyethylene and polystyrene, on the skin dose were analysed. The results demonstrated that the current RS design had a negligible effect on the skin dose, whereas the RS significantly impacted the isocenter beam size. The skin dose was increased considerably when the RS was placed close to the phantom. Moreover, the magnitude of the increase was related to the thickness of the inserted RS. Meanwhile, the results also revealed that the secondary proton primarily contributed to the increased skin dose.

• 한국산학기술학회논문지
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• 제13권5호
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• pp.2278-2284
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• 2012

파노라마방사선촬영 시 방사선감수성이 높은 갑상선의 방사선 피폭을 최소화하면서 진단에 유용한 영상을 얻기 위하여 조직등가물질인 보루스(bolus)를 차폐체로 사용하여 피폭선량 감소효과를 측정하였다. 실험은 2011. 6. 1일부터 6. 30일까지 두경부팬톰을 이용하여 갑상선 위치의 표면입사선량과 심부흡수선량을 측정하였다. 그 결과 갑상선 부위 입사표면선량은 평균 43.84 ${\mu}Gy$이었고, 10 mm 두께의 보루스로 만든 갑상선보호대에서는 평균 28.39 ${\mu}Gy$로 15.45 ${\mu}Gy$(35.24%)가 감소되었다. 20 mm 갑상선보호대를 착용했을 경우에는 평균 25.38 ${\mu}Gy$로 미착용 시 평균 43.84 ${\mu}Gy$보다 18.46 ${\mu}Gy$(42.10%)가 감소되었다. 그리고 표면에서 20 mm 깊이에서는 10 mm 두께의 갑상선보호대는 선량 감소효과가 없었고, 20 mm 갑상선보호대를 착용했을 경우에는 0.06 mSv (20%)의 선량감소효과가 있었다.

• 대한수의학회지
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• 제34권4호
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• pp.833-842
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• 1994

To elucidate the protective effects of Lactobacillus acidophilus-fermented milk against cadmium toxicity, the effects of administration of L acidophilus-fermented milk on hematological values and histopathological changes in cadmium-treated rats were investigated. The experimental rats were divided into 2 groups that were consisted of the one group administered with cadmium alone, and the other group administered with cadmium mixed with the fermented milk. Each group was orally administered with different doses of cadmium such as $1.7{\mu}g/g$ bw/day, $3.4{\mu}g/g$ bw/day, $6.8{\mu}g/g$ bw/day, and $13.6{\mu}g/g$ bw/day, respectively, for 1 to 8 weeks. Hematological values and enzyme activities, histopathological changes of kidney tissues were examined for the experimental groups. The values of RBC, WBC, and Hb in the groups administered with cadmium mixed with the fermented milk showed no significant differences to those of the groups administered with cadmium alone, but Hct showed significant reducing values. The activities of glutamic oxaloacetic transaminase(GOT) and glutamic pyruvic transaminase (GPT) in serum were significantly reduced than those of the groups administered with cadmium alone, at the low dose of cadmium treated groups. But alkaline phophatase(ALP) and lactate dehydorgenase(LDH) were significantly reduced at the high dose of cadmium treated groups. In histopathological study, a severe acute tubular necrosis of the convoluted tubules and distalation of tubules were showed in the groups administered with cadmium alone, but the kidney tissues of the groups administered with cadmium mixed with the fermented milk were similar to those of the normal group. In conclusion, the above results would suggest that L acidophilus-fermented milk has reducing effects on cadmium toxicity, at the low dose of cadmium administration.

• 한국임상수의학회지
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• 제16권2호
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• pp.352-362
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• 1999

Thiopental sodium is known as ultrashort-acting barbiturates and can be employed advantageously for numerous conditions. But thiopental has the side effects of cardiovascular and respiratory systems which has barbiturates and are depend on the dose of thiopental. The side effects are reduced when the thiopental is preceded by a tranquilizer and sedative. In these drugs, benzodiazepines have the minimal effects of cardiovascular and respiratory systems. In this study, the effects of midazolam preanesthetic administration, followed by thiopental anesthetic induction, on cardiovascular system and thiopental induction requirement were studied in 14 mixed breed dogs. Cardiovascular data were recorded baseline, after premedication of saline 0.45 ml/kg or midazolam 0.1, 0.2, 0.4, 0.8 mg/kg, intubation, and 5, 10, 15, 20, 30 minutes after intubation. Extubation, head-up, sternal recombency, standing, and walking recovery times were recorded. The results were summarized as follows; (1) The 0.1, 0.2, 0.4, and 0.8 mg/kg dosages of midazolam insignificantly decreased thiopental dose requirement necessary to accomplish intubation by 6, 20, 21 and 28%. (2) The 0.1, 0.2, 0.4, and 0.8 mg/kg dosages of midazolam insignificantly reduced the times of extubation, head-up, sternal recumbency, standing, and walking recovery. (3) Midazolam was effective in reducing the frequency and duration of arrhythmia after intubation. (4) Heart rates of preanestheic midazolam administraion groups increased after thiopental injection which insignificantly changed smaller than those of control group. (5) Arterial blood pressures did not vary significantly among groups.

• 생물정신의학
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• 제5권2호
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• pp.263-277
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• 1998

Conventional high-dose antipsychotics tend to result in more side effects, negative symptoms and dysphoria, and at the same time lower the cognitive function which is already impaired in most schizophrenics. Florid psychotic symptoms, negative symptoms and cognitive impairment greatly impede psychosocial performance and eventual reintegration into society. The reduction of symptom and the improvement of cognitive funtions and social skills are therefore central to the psychiatric rehabilitation process. The purpose of this study was to evaluate the dose-reduction effects of antipsychotics on chronic schizophrenics prescribed conventional high-dose antipsychotics more than 1,500mg equivalent of chlorpromazine. Fifty-one chronic schizophrenics who maintained high-dose antipsychotics for more than three months were randomly assigned to two groups : 20 patients comprised the dose-maintaining group and 31 patients made the dose-reduction group. Over a sixteen weekperiod Positive and Negative Syndrome Scale(PANSS), Extrapyramidal Symptom(EPS), Nurses' Observation Scale for Inpatient Evaluation(NOSIE-30), Continuous Performance Test(CPT), Quality of Life(QOL), and haloperidol/reduced haloperidol blood levels were determined at the base line and after 2, 4, 6, 8, 12, 16 weeks to evaluate the dose reduction effects of high-dose antipsychotics. The results were as follows : 1) Dose-reduction is highly effective in reducing positive and negative symptoms, and general psychopathology. Effects were most prominent at 8, 12, 16 weeks. Among the dose reduction group, positive symptoms in positive symptom group and negative symptoms in negative symptom group were more reduced. 2 Extrapyramidal symptoms showed no significant difference between two groups. But the EPS was reduced time after time within two groups. 3) Hit rates of Continuous Performance Test, which indicate attentional capacity, increased significantly after dose reduction. 4) Haloperidol and reduced haloperidol blood levels decreased until the 4th week, after which they were constant. 5) Total scores of Nurses' Observation Scale for Inpatient Evaluation were unchanged between the two groups. But among the indices, social interest and personal neatness were improved in the dose-reduction group and retardation was aggrevated in the dose-maintaining group. 6) Total quality of life scores were unchanged between two groups. But in the dose maintaining group, satisfaction scores of attention, autonomy, and interpersonal relationship decreased progressively. These findings suggest that the dose reduction of antipsychotics for chronic schizophrenics on programs of high-dose antipsychotics were effective. Dose reduction should therefore be implemanted to spread the rehabilitation and improve quality of life for chronic schizophrenics.

• 대한디지털의료영상학회논문지
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• 제15권2호
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• pp.45-53
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• 2013

Purpose : Fixed way of mAs previously Low Extremity Computed Tomography Angiography(LECTA) examination were used. Automatic Current Selection(ACS) to use for the purpose of reducing the dose when Low Extremity Computed Tomography Angiography examining patients. Materials and methods : Were analyzed from July 2011 to July 2012 MDCT examination of Dose Length Product(DLP) LECTA 116 Case. It was defined as previous inspection methods(Old protocol). CT workstation is set to 100 mAs and 150 mAs protocol based on the patient's weight 70kg examined by LECTA. We defined as 'New protocol' that applies to ACS. The data collection period are 76 cases from October 2012 to January 2013 Results : 1. Average Total DLP of 'Old protocol' is 3602.943 $mGy^*cm$. 2. Average Total DLP of 'New protocol' is 1762.977 $mGy^*cm$. 3. Due to the 'New Protocol' use of Total DLP was reduced by approximately 51 %. Phase-specific dose reduction is as follows. Pre(33.62 %), Artery(64.63 %), Delay(49.0 %) 4. Using One way ANOVA Analysis of fluctuations obtained DLP is as follows. 'Old protocol', 'New protocol' a value of P < 0.001, P = 0.882 values were obtained. Conclusions : Dose reduction of 51 % is a useful study that proves. The results obtained using the ACS, the effects of a dose reduction of 51 % was obtained. Therefore, it has been proven to be a useful way. Statistics using SPSS version came out of the 'Old protocol' P-value P < 0.0001. This result means that the DLP a large difference values. On the other hand, The results of the 'New protocol' was P = 0.882. These results means to that small and regularly was fluctuations of the dose. The use of ACS, you can get a reduction of the dose and will able to get the effect of reducing the dose errors.

• Journal of Medicine and Life Science
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• 제18권1호
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• pp.1-10
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• 2021

Omega-3 fatty acids (eicosapentaenoic acid [EPA] and docosahexaenoic acid [DHA]) may be beneficial for the primary and secondary prevention of cardiovascular events (CVEs), especially in patients with myocardial infarction or heart failure with reduced ejection fraction. For this purpose, one to two seafood meals per week is preferentially recommended. Omega-3 fatty acids with a high-dose EPA formula (4 g/day) may be more effective than EPA+DHA mixed supplements for the secondary prevention of CVE. Krill oil also contains omega-3 fatty acids, but at a much lower dose compared to fish oil. Supplemental vitamins and minerals have not shown the preventive effects on CVE in prospective, and randomized clinical trials, except for one Chinese study showing the stroke prevention effects of folic acid. The clinical benefit of chelation therapy in reducing CVEs is uncertain.

• 대한본초학회지
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• 제28권3호
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• pp.25-31
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• 2013

Objectives : To develop a natural antioxidant and anti-hemolytic agents, we investigated the effects of ethanol extracts of Carpesii Fructus and Farfarae Flos. Methods : Aerial parts of Carpesii Fructus and Farfarae Flos were extracted with 80% ethanol. Antioxidant activity of Carpesii Fructus or Farfarae Flos extract was evaluated by employing three different assays, i.e., 1,1-diphenyl-2-picryl hydrazyl (DPPH), 2,2'-azino-bis (3-ethylbenzthiazoline-6-suphonic acid) diammonium (ABTS) scavenging and reducing power activities. Also, anti-hemolytic activity of Carpesii Fructus or Farfarae Flos extract was determined using [2,2'-azobis (2-methylpropionamidine) dihydrochloride (AAPH)]-induced hemolysis, glutathione (GSH) depletion and malondialdehyde (MDA) formation in normal rat red blood cells (RBC) or plasma. Results : The extracts obtained from Carpesii Fructus and Farfarae Flos dose-dependently increased the scavenging activity on DPPH- or ABTS-induced radicals and the reducing power activities. Carpesii Fructus and Farfarae Flos were similar to the scavenging activity and the reducing power of butylated hydroxy anisole effect at high concentration ($1,000{\mu}g/mL$). RBC oxidative hemolysis and plasma MDA formation induced by AAPH were significantly suppressed by the extracts of Carpesii Fructus and Farfarae Flos in a dose-dependent manner. Also, Carpesii Fructus and Farfarae Flos extracts prevented the depletion of cystosolic antioxidant GSH in RBCs. Carpesii Fructus generally had better than the free radical scavenging activity, the reducing power and anti-hemolytic effects of Farfarae Flos. Conclusions : These results suggest that Carpesii Fructus and Farfarae Flos may have value as the potential antioxidant and anti-hemolytic medicinal plant.

• Biomolecules & Therapeutics
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• 제24권4호
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• pp.418-425
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• 2016

We measured anti-nociceptive activity of prim-o-glucosylcimifugin (POG), a molecule from Saposhnikovia divaricate (Turcz) Schischk. Anti-nociceptive or anti-inflammatory effects of POG on a formalin-induced tonic nociceptive response and a complete Freund's adjuvant (CFA) inoculation-induced rat arthritis pain model were studied. Single subcutaneous injections of POG produced potent anti-nociception in both models that was comparable to indomethacin analgesia. Anti-nociceptive activity of POG was dose-dependent, maximally reducing pain 56.6% with an $ED_{50}$ of 1.6 mg. Rats given POG over time did not develop tolerance. POG also time-dependently reduced serum TNF${\alpha}$, IL-$1{\beta}$ and IL-6 in arthritic rats and both POG and indomethacin reduced spinal prostaglandin E2 ($PGE_2$). Like indomethacin which inhibits cyclooxygenase-2 (COX-2) activity, POG dose-dependently decreased spinal COX-2 content in arthritic rats. Additionally, POG, and its metabolite cimifugin, downregulated COX-2 expression in vitro. Thus, POG produced potent anti-nociception by downregulating spinal COX-2 expression.

• 생약학회지
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• 제38권2호통권149호
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• pp.152-156
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• 2007

Protein-bound polysaccharide is derived from Acanthopananx senticosus by the cold water extraction. The aim of the study was to evaluate the effects of PS against weight loss and hematological change as a indication of toxicity produced by the treatment of cisplatin. PS protected the weight loss caused by cisplatin (6 mg/kg) and significantly recovered hematological change. Treatment of PS showed the recovery on the weight loss and hematological change as indicators of toxicity of cisplatin treatment. By increasing lymphocyte proliferation and cytokine production, PS may be highly effective in protecting against cisplatin-induced toxicity. The results suggest PS might have a role in reducing toxicity or permitting larger dose of cisplatin to be given.