• Applied Microscopy
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• v.47 no.3
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• pp.86-94
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• 2017

In this study, we will describe a new design of carbon nanotubes tip. Single-walled carbon nanotubes produced using high-pressure CO over Fe particles (HiPCO) at CNI, Houston, TX used in this study. These tips were manufactured by employing a drawing technique using glass puller. Field electron microscopies with tips (cathode) to screen (Anode) separation of ~10 mm was used to characterize the electron emitters. The system was evacuated down to base pressure of (${\sim}10^{-8}$ mbar) when baked at up to (${\sim}200^{\circ}C$) over night. An electron field emission patterns, as well as current versus voltage characteristics and Fowler-Nordheim plots, are discussed.

• The Korean Journal of Physiology and Pharmacology
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• v.6 no.1
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• pp.41-46
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• 2002

Effect of cadmium (Cd) intoxication on renal acid-base regulation was studied in adult male Sprague-Dawley rats. Cd intoxication was induced by subcutaneous injections of $CdCl_2$ at a dose of 2 mg Cd/kg/day for $3{\sim}4$ weeks. In Cd-intoxicated animals, arterial pH, $PCO_2$ and plasma bicarbonate concentration decreased, showing a metabolic acidosis. Urine pH and urinary bicarbonate excretion increased and titratable acid excretion decreased with no change in ammonium excretion. In renal cortical brush-border membrane vesicles derived from Cd-exposed animals, the $Na^+/H^+$ antiporter activity was significantly attenuated. These results indicate that chronic exposures to Cd impair the proximal tubular mechanism for $H^+$ secretion (i.e., $Na^+/H^+$ antiport), leading to a metabolic acidosis.

• Convergence Security Journal
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• v.4 no.2
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• pp.53-60
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• 2004

We describe CHAP authentication for roaming service method of visited ISP subscriber on GPRS network. We also illustrate how visited mobile ISP subscriber can access ISP server and authenticate RADIUS in home network via Gateway GPRS Support Node (GGSN) on GPRS/UMTS network for wireless internet service and roaming. For this we propose the modified CHAP message format, PCO Message format at MT, and interworking message and format between GGSN and RADIUS in home ISP network for wireless internet service of mobile ISP subscriber at GPRS network in this paper. We also show authentication results when visited mobile ISP subscriber via CHAP at GPRS network accesses the RADIUS server in home ISP network.

• Journal of Chest Surgery
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• v.27 no.9
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• pp.770-778
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• 1994

Here analized the chest physiologic changes caused by various degrees of spontaneous pneumothorax in 77 patients admitted in Pusan National University Hospital from Jan. 1991 to Aug.1992. The results were summarized as follow: 1. There were 59 patients of primary spontaneous pneumothorax and 18 of secondary spontaneous pneumothorax. 2. The intrapleural pressure risings were paralled to the increasing sizes of pneumothorax, especiallythe intrapleural pressure changes were significant in large pneumothorax. In the secondary spontaneous pneumothoraces the intrapleural pressure were relatively higher than primary in the same sizes of pneumothorax. 3. The intensity of chest pain was paralled to the increasing sizes and intrapleural pressures of the pneumothorax, but the degrees of dyspnea had no linear interrelationship. 4. The pulse rate, cardiac output, and arterial PO2 started to change from positive intrapleural pressure, and significant changes were noted between 6 to 9 mmHg of intrapleural pressure. But the arterial PCO2 changes had no interrelationship to the degrees of pneumothorax.

• Journal of Chest Surgery
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• v.10 no.1
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• pp.28-37
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• 1977

Authors had performed experimental study for ventilatory functions & pulmonary hemodynamics following reimplantation of lung. Preoperative & postoperative hemodynamic studies were obtained. A significant reduction in arterial $PO_2$ and $PCO_2$ was observed with the first few days. But these changes returned to near control levels from 1 week after operation in long-term survivors. Also abnormal pulmonary hemodynamic values returned toward control levels within 1 to 3 weeks, with the exception of a residual increase in pulmonary vascular resistance. Microscopically minimal focal pulmonary edema and limited alveolar infiltration developed in the reimplanted lung. But these changes never increased after the their postoperative day and were completely resolved by 1 to 3 weeks after autotransplantation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.6
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• pp.869-873
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• 2014

Cardiorespiratory variables were measured in flounder Paralicthys olivaceus exposed to acidified seawater equilibrated with a gas mixture containing 5% $CO_2$ gas for 72 h at $20^{\circ}C$. It was found that $CO_2$ produced a significant increase in arterial $PCO_2$ ($PaCO_2$) and significant decreases in arterial pH (pHa). $CO_2$ transiently increased heart rate within 30 min of exposure. After cardiac output was elevated by the increase in heart rate within 30 min, was then reduced by the decrease in both stroke volume and heart rate. The heart responses of flounder differ from those of yellowtail to high $CO_2$ environment.

• 대한생식의학회:학술대회논문집
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• 2006.11a
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• pp.67-80
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• 2006

비만 특히 복부비만은 여성의 임신 및 출산에 많은 악영향을 미친다. 비만이 가임력에 영향을 미치는 기전은 명확히 밝혀지지는 않았지만, functional hyperandrogenism과 insulin resistance에 수반된 hyperinsulinemia가 중요한 역할을 하리라 여겨진다. 또한 지방조직은 활발하게 대사 작용이 일어나는 장소로서 steroid hormone을 modification 시키고, 여러 가지 adipokine들을 분비시키는데 이런 지방조직의 분비물들은 생식계에 영향을 미친다. 비만이 생식계에 미치는 영향은 간략히 다음 표와 같이 정리할 수 있다 (Table 3). 특히 PCOS 환자에서 비만은 hyperinsulinemia에 의한 난소의 steroidogenesis 증가와 SHBG의 감소에 연관되어 hyperandrogenism 과 무배란의 원인으로 작용한다. 비만은 약물에 의한 배란유도 및 체외수정의 성공률 또한 떨어뜨리며， 임신이 되더라도 자연 유산, 조산, 임신성 당뇨, 임신성 고혈압 등의 위험은 높인다. 이와 같이 최근 급격히 증가하는 비만은 여성의 건강 특히 생식계에 많은 문제를 야기시킨다. 특히 청소년기의 비만은 성인이 된 뒤 PCOS로 발전하여 불임, 심혈관 질환 등과 같은 많은 합병증을 일으킬 수 있으므로 세심한 주의를 기울여야 하겠다.

• 대한생식의학회:학술대회논문집
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• 2002.11a
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• pp.98.1-98.1
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• 2002

• Ceramist
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• v.21 no.4
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• pp.366-377
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• 2018

Solid oxide fuel cells (SOFCs) are promising eco-friendly energy conversion system due to their high efficiency, low pollutant emission and fuel flexibility. High operating temperatures, however, leads to the crucial drawbacks such as incompatibility between the components and high thermal stress. Proton-conducting ceramic fuel cells (PCFCs) with proton-conducting oxide (PCO) materials are new types of fuel cells that can solve the problems of conventional SOFCs. Many studies have been proceeded to improve the performance of electrolytes and electrodes, and triple conductive oxides (TCOs) have attracted significant attention as high performance PCFC electrodes.

• Tuberculosis and Respiratory Diseases
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• v.43 no.2
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• pp.221-227
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• 1996

Background : Measurement of pleural fluid constituents are of value in the diagnosis of pleural effusions and in the seperation of exudates from transudates. The position of the patient(sitting or lying) prior to thoracentesis may result in difference in the measurement of these constituents. The purpose of this study is to determine whether postural differences in pleural fluid constituents exist, and if so, whether they are of any clinical significance. Method : 41 patients with pleural effusions on chest roentgenography were prospectively studied. The fluid cell counts, partial gas tension, and concentrations of chemical constituents were compared in the supine and upright positions. Results : 1) A total of 10 patients were found to have an transudative effusion. In the transudates there was no significant difference in pleural fluid constituents according to posture change. 2) A total of 31 patients were found to have an exudative effusion. Statistically significant postural changes were noted in pH, WBC counts, protein, and LDH concentrations in the exudates. It may be due to postural sedimentary effect in the pleural space. 3) The PCO2 measurements and glucose concentration were not affected by changes in position in exudates or transudates. Conclusion : Postural sedimentary effect occurs in the pleural space with reference to the measurement of certain pleural fluid constituents when an inflammatory process is present. Therefore it is recommended that thoracentesis after 30 minutes in the sitting position should be performed.