• Journal of Positioning, Navigation, and Timing
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• 제11권2호
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• pp.83-89
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• 2022

For precise GNSS applications, the antenna phase center correction (PCC) is absolutely required. The PCC magnitude can reach the centimeter level with the antenna structure. In the present study, we first investigate the phase center offset (PCO) and phase center variation (PCO) of three different antenna models in two different reference frames, IGS08/igs08.atx and IGS14/igs14.atx. Clear L1 and L2 PCO differences were found between IGS08 and IGS14. In addition, the PCV showed characteristics that is dependent upon the signal direction (azimuth and elevation angle). The remarkable thing is that the changes of a Dorne Margolin choke-ring antenna model (AOAD/MT DOME) was very small in two reference frames. In order to analyze changes in positions according to different reference systems, GNSS data obtained from DAEJ, SUWN, and TSKB stations were processed by the precise point positioning (PPP) method. We suggest that an antenna PCO/PCV can affect the precise GNSS positioning on the order of several millimeters in two different reference frames.

• 한국물환경학회지
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• 제21권1호
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• pp.84-91
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• 2005

$TiO_2-catalyst$ suspensions work efficiently in Photocatalytic oxidation (PCO) for wastewater treatment. Nevertheless, once photocatalysis is completed, separation of the catalyst from solution becomes the main problem. The PCO of Cu(II)-EDTA was studied to determine the reusability of the titanium dioxide catalyst. Aqueous solutions of $10^{-4}M$ Cu(II)-EDTA were treated using illuminated $TiO_2$ particles at pH 6 in a circulating reactor. $TiO_2$ was reused in PCO system for treatment of Cu(II)-EDTA comparing two procedures: reuse of water and $TiO_2$ and reuse of the entire suspension after PCO of Cu(II)-EDTA. The results are as follows; (i) Photocatalytic efficiency worsens with successive runs when catalyst and water are reused without separation and filtration, whereas, when $TiO_2$ is separated from water, the reused $TiO_2$ is not deactivated. (ii) The $TiO_2$ mean recovery (%) with reused $TiO_2$ was 86.4%(1.73g/L). Although the mean initial degradation rate of Cu(II)-EDTA and Cu(II) was lower than that using fresh $TiO_2$, there was no significant change in the rate during the course of the three-trial experiment. It is suggested that Cu(II)-EDTA could be effectively treated using an recycling procedure of PCO and catalyst recovery. (iii) However, without $TiO_2$ separation, the loss of efficiency of the PCO in the use of water and $TiO_2$ due to Cu(II), DOC remained from previous degradation and Cu(II)-EDTA added to the same suspension was observed after 2 trials, and resulted in the inhibition of the Cu(II)-EDTA, Cu(II) and DOC destruction.

• Applied Microscopy
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• 제39권1호
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• pp.1-7
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• 2009

사람에서의 PCO와 몇몇 측면에서 유사한, 실험적으로 유발된 다낭성난소(polycystic ovary, PCO)는 장기간 작용하는 estradiol valerate (EV)에 의해 유발된다. 랫드에서 스테로이드로 유발한 PCO 모델에서 홍삼 총사포닌의 역할에 대한 우리의 이전연구는 전침이 난소의 nerve growth factor (NGF) 농도를 조절하는 것을 검증하였다. 실제로 PCO와 관련된 난소 기능부전의 병리기전에서 신경성 요소의 관련성은 난소로의 교감신경유출(sympathetic outflow)의 증가로 인해 높아진다. 따라서 본 연구에서는 치료제로서의 GTS 투여가 PCO를 유발한 랫드에서 교감신경 활성을 조절할 것이라는 가설을 시험해보고자 하였다. 본 연구에서는 스테로이드로 유발한 PCO에 내재하고 있는 병태생리학적 과정과 연관된 NGF 단백질과 NGF mRNA를 분석함으로써 이루어졌다. PCO가 유발된 랫드에서 EV 대조군은 oil 대조군과 비교하였을 때 유의적으로 높은 NGF mRNA의 발현을 나타내었으며, GTS 투여군은 EV 대조군에 비해 유의적으로 낮은 NGF mRNA의 발현을 나타내었다. 그러나 NGF 단백질은 oil 대조군에 비해 EV 대조군과 GTS 투여군에서도 유의적인 변화를 발견할 수 없었다. 이러한 결과는 EV가 설치류에서 낭종 형성과 무배란을 유발하는 병리학적 단계의 구성요소일 수 있는 난소의 신경향성 단계(neurotrophic state)를 조절한다고 생각할 수 있다.

• Journal of Korean Neurosurgical Society
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• 제66권4호
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• pp.418-425
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• 2023

Objective : Deciphering the anatomy of posterior communicating artery (PCoA) aneurysms in relation to surrounding structures is essential to determine adjuvant surgical procedures. However, it is difficult to predict surgical structures through preoperative imaging studies. We aimed to present anatomical structures using preoperative high-resolution three-dimensional proton density-weighted turbo spin-echo magnetic resonance (PDMR) imaging with simple classification. Methods : From January 2020 to April 2022, 30 patients underwent PDMR before microsurgical clipping for unruptured PCoA aneurysms in a single tertiary institute. We retrospectively reviewed the radiographic images and operative data of these patients. The structural relationship described by PDMR and intraoperative findings were compared. Subsequently, we classified aneurysms into two groups and analyzed the rate of adjuvant surgical procedures and contact with the surrounding structures. Results : Correlations between preoperative PDMR predictions and actual intraoperative findings for PCoA aneurysm contact to the oculomotor nerve, temporal uncus, and anterior petroclinoid fold (APCF) reported a diagnostic accuracy of 0.90, 0.87, and 0.90, respectively. In 12 patients (40.0%), an aneurysm dome was located on the plane of the oculomotor triangle and was classified as the infratentorial type. Compared to the supratentorial type PCoA aneurysm, adjuvant procedures were required more frequently (66.7% vs. 22.2%, p=0.024) for infratentorial type PCoA aneurysm clipping. Conclusion : Preoperative PCoA aneurysm categorization using PDMR can be helpful for predicting surgical complexity and planning of microsurgical clipping.

• Clinical and Experimental Reproductive Medicine
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• 제21권1호
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• pp.83-88
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• 1994

This study was designed to investigate the relationship between insulin resistance and obesity in the pathogenesis of polycystic ovarian syndrome(PCO). Twenty-two women with PCO, of whom thirteen were non-obese with body mass index(BMI, kg/$m^2$) of <25 and nine were obese with BMI${\geq}$25 were studied. Eight non-obese control women and seven obese control women were studied. Serum concentrations of testosterone, lutenizing hormone(LH)/follicle-stimulating hormone(FSH) ratio, and insulin-like growth factor I (IGF-I) were found to be significantly higher(P<0.05) in PCO women compared with control women, which clearly is not related to obesity. Serum glucose, insulin, and C-peptide levels were measured during a 2-hour oral glucose tolerance test(OGTT). Non-obese and obese women with PCO both(P<0.05) compared with control women demonstrated significant hyperinsulinemia after OGTT. The degree of hyperinsulinemia was found to be significantly higher in the obese women with PCO compared with the non-obese women with PCO. We concluded that obesity may contribute to hyperinsulinemia, however may not playa central role in the pathogenesis of PCO.

• 대한한방부인과학회지
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• 제21권2호
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• pp.1-16
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• 2008

Purpose: In this rearch, we made a plan to investigate the effects of Changbuyeukgun-Tang(CET) on the polycystic ovary(PCOS) induced by estradiol valerate(EV) in rats. PCO was induced by single intramuscular injection with EV(4㎎) in female rats. Rats(n=8) in normal group were injected with sesame oil and orally administrated distilled water for 8weeks Rats in PCO control group(n=8) were injected with EV and orally administrated distilled water for 8weeks. Rats in CET treated group(n=8) were injected with EV and orally administrated CET for 8weeks. Methods: We measured the weights of the body, the ovary, the uterus and the adrenal gland. And also, we analyzed ovarian histopathology, NGF and CRF immunohistochemistry. Results: The results were as follows1. the weights(㎎) of the ovaries in CET treated group were significantly increased(p<0.001) compared with PCO control group. 2. the number of the mature follicles in CET treated group were significantly increased(p<0.01) compared with PCO control. 3. the number of the atresia follicles in CET treated group were significantly decreased(p<0.01) compared with PCO control. 4. the number of the corpora in CET treated group were significantly increased(p<0.05) compared with PCO control. 5. the expressions of NGF-immunoreactive cells in the ovarian granulosa cells of rats in CET treated group were less observed than PCO control group. Conclusion: According to these results, we finally concluded that Changbuyeukgun-Tang(CET) has the inhibitory effect on the development of EV-induced polycystic ovary. And we deduced that the effect of it may be related to the decreased NGF activities in the ovary.

• 대한응급의학회지
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• 제29권6호
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• pp.578-584
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• 2018

Objective: This study examined the initial partial pressure of carbon dioxide ($PCO_2$) as a possible indicator of prehospital ventilation and its association with prehospital i-gel in out-of-hospital cardiac arrest (OHCA) patients. Methods: The demographics and arrest parameters, including i-gel insertion and initial arterial blood gas analysis, of OHCA patients who visited the emergency department were analyzed retrospectively. Linear regression analysis was performed to examine the association between i-gel insertion and the initial $PCO_2$. Results: A total of 106 patients were investigated. Fifty-six patients had prehospital i-gel insertion and 50 patients did not have a prehospital advanced airway. The initial $PCO_2$ was higher in the i-gel group than the no advanced airway group (105.2 mmHg [77.5-134.9] vs. 87.5 mmHg [56.8-115.3], P=0.03). Prehospital i-gel insertion was associated with a higher initial $PCO_2$ level (${\beta}$ coefficient, 20.3; 95% confidence interval, 2.6-37.9; P=0.03). Conclusion: Prehospital insertion of i-gel was associated with higher initial $PCO_2$ values in OHCA patients compared to no advanced airway.

• 한국수정란이식학회:학술대회논문집
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• 한국수정란이식학회 2002년도 국제심포지엄
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• pp.112-112
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• 2002

Under normal conditions, women produce a single dominant follicle that participates in a single ovuation each menstrual cycle. But Polycystic ovary syndrome(PCOS) conditions, folliculogenesis does not proceed normally. This condition leads to the accumlation of large numbers of small graffian follicles in which the theca interstitial cells (TIC) produce abnormally large amounts of androgen. PCOS is probably the most common endocrine disorder, affecting women of reprodutive age with 5-10% prevalence estimate. Chronic anovulation, hyperandrogenism, hirsutism, obesity, infertility and polycystic ovaries are clinical hallmarks of women with PCOS. Its etiology remains unknown. To investigate the gene expression pattern of ovary in PCO-induced rat, we used cDNA expression analysis. Total RNA was extracted from the ovary of PCO-induced rat and reverse-transcribed in the presence of［$\alpha$$^{32}$P］-dATP Which were hybridized to Atlas$^{TM}$ Rat Toxicology 1.2 array (Clontech) representing approximately 1176 rat genes. We compared gene expression between ovary of pco-induced immature female rats and control. Differential gene expression profiles were revealed (LIFR-alpha, ADRA1A, Heat shock 90-kDa protein A, PDGFRA). Reverse transcription-polymerase chain reaction(RT-PCR) was used to validate the relative expression pattern obtained by the cDNA array. The precise relationship between the altered expression of genes and PCO is a matter of further investigation. This study was supported by Korea Science and Engineering Foundation(KOSEF)

• 대한한방내과학회지
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• 제11권2호
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• pp.43-52
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• 1990

The following results were obtained from the observation on the change of plasma cortisol concentration and arterial blood $PO_2,\;PCO_2$ in the experiment of intravenous and oral administration of Chung Sang Bo Ha Tang Water Extract in the rabbit. 1. In intravenous administration, the plasma cortisol conce-ntration increased significantly about 2 hours after with a dose of $0.2m{\ell}/kg$, while the case of $0.4m{\ell}/kg$ reveals this significant increase of concentration about 3 hours after. 2. In oral administration, a significant increase of the plasma cortisol concentration was shown about 2 and 4 hours after with a dose of $1.2m{\ell}/kg$, on the other hand, an increase of concentration was shown at each hour in the case of $0.2m{\ell}/kg$, but it was not significant. 3. In oral administration, $PO_2$ in arterial blood increased significantly in the case of $0.2m{\ell}/kg$, and both the case of $0.1m{\ell}/kg$ and that of $0.2m{\ell}/kg$ gave a significant decrease of $PCO_2$ in arterial blood. With these results, it is verified that Chung Sang Bo Ha Tang has therapeutic effects on JISU(止嗽), JEONG CHEON(定喘), GEO DAM(祛痰) because intravenous and oral administration of it increases the plasma cortisol concentration, However, in the examination of $PO_2$ and $PCO_2$ in arterial blood, any remarkable result was not obtained.

• 대한한방부인과학회지
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• 제24권2호
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• pp.52-67
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• 2011

Objectives: This study was designed to investigate the effects of Jokyeongjongok -Tang(JJT) on the progression of the estradiol valerate(EV)-induced polycystic ovaries(PCO) in rats. Methods: PCO was induced by single intramuscular injection with estradiol valerate(EV)(4 mg) in female rats. Normal group(n=8) were injected with sesame oil and orally administrated distilled water for sixty days. PCO control group (n=8) were injected with EV and orally administrated distilled water for sixty days. JJT treated group(n=8) were injected with EV and orally administrated JJT for same duration. At the end day of experiment, we measured weights of body, ovaries, adrenal glands and uterus. The histopathological changes of ovaries were also evaluated. And we observed the NGF and CRF expression by immunohistochemistry. Results: The results were as follows - The weights(mg) of ovaries of JJT treated group($58.4{\pm}9.4$) were significantly increased(p<0.01) compared with PCO control group($42.3{\pm}8.5$). - The numbers of mature follicles of JJT treated group($10.1{\pm}2.5$) were significantly increased(p<0.01) compared with PCO control group($6.1{\pm}2.1$). - The numbers of cystic follicles of JJT treated group($1.8{\pm}1.4$) were significantly decreased(p<0.05) compared with PCO control group($3.8{\pm}1.5$). - The expressions of NGF-immunoreactive cells in the ovaries of JJT treated group were weaker than PCO control group. Conclusions: From the above results, we concluded that Jokyeongjongok-Tang (JJT) contributes to a normal maturation of follicles and has the effects of promoting a normal ovulation. And these effects may be related with the decreased NGF activities in the ovaries.