• Investigative Magnetic Resonance Imaging
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• 제19권3호
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• pp.137-145
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• 2015

Purpose: To investigate correlations of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor type 2 (HER2) statuses with magnetic resonance imaging (MRI) features and clinicohistological characteristics in patients with invasive lobular carcinoma (ILC). Materials and Methods: Data from 64 histologically confirmed ILCs were analyzed retrospectively. Preoperative breast MRI was reviewed for morphology and dynamic contrast-enhanced kinetics of the tumor. Pathologic reports were reviewed for ER, PR, and HER2 positivity, tumor size, lymph node metastasis, and the number of metastatic lymph nodes. Furthermore, there was an investigation of the MRI features and clinicohistologic characteristics, according to the ER, PR, and HER2 statuses. Results: A significant difference in MRI features and clinicohistological tumor characteristics were observed only in relation to PR status. Of the 64 ILCs, 10 (15.6%) were PR negative. PR negative cancers, compared with PR positive cancers, were more likely to present as non-mass enhancement (P = 0.027); have a significantly larger mean tumor size ($5.00{\pm}1.05cm$ vs. $2.57{\pm}0.21cm$, P = 0.021); and have significantly more metastatic lymph nodes (P = 0.010). Conclusion: PR negative ILC presented more frequently as non-mass enhancement on MRI, with larger tumors and increased numbers of metastatic lymph nodes. Therefore, the PR status plays an important role in determining MRI features and clinicohistological characteristics of ILC.

• 한국전기전자재료학회논문지
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• 제13권8호
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• pp.667-674
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• 2000

The stability of ZnO-Pr$_{6}$/O$_{11}$-CoO-Er$_{2}$/O$_3$based varistors was investigated with Er$_{2}$/O$_3$additive content of the range 0.0 to 2.0 mol%. All varistors sintered at 130$0^{\circ}C$ exhibited the thermal runaway within short times even under weak d.c. stress. As a result these varistors were completely degraded. On the contrary the stability of varistors sintered at 135$0^{\circ}C$ was far better than that of 130$0^{\circ}C$. In particular the varistors added with 0.5mol% Er$_{2}$/O$_3$ which the nonlinear exponent is 34.83 and the leakage current is 7.38 $mutextrm{A}$ showed a excellent stability which the variation rate of the varistors voltage the nonlinear coefficient and the leakage current is below 1%, 2%, and 3.5% respectively even under more severe d.c. stress such as (0.80 V$_{1mA}$9$0^{\circ}C$/12h)+(0.85 V$_{1mA}$115$^{\circ}C$/12h)+(0.90 V$_{1mA}$12$0^{\circ}C$12h) Consequently it is estimated that the ZnO-0.5 mol% Pr$_{6}$/O sub 11/-1.0 mol% CoO-0.5 mol% Er$_{2}$/O sub 3/ based varistors will be used to develop the advanced Pr$_{6}$/O$_{11}$-1.0 mol% CoO-0.5 mol% Er$_{2}$/O$_{3}$ based varistors will be used to develop the advanced Pr$_{6}$/O$_{11}$-based ZnO varistors having the high performance and stability in future. future.ure. future.

• Asian Pacific Journal of Cancer Prevention
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• 제15권19호
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• pp.8441-8445
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• 2014

Background: Paired-like homeodomain transcription factor 2 (PITX2) is another new marker in breast carcinoma since hypermethylation at P2 promoter of this gene was noted to be associated with poor prognosis. We investigated the expression of PITX2 protein using immunohistochemistry in invasive ductal carcinoma and its association with the established growth receptors such as estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth receptor 2 (HER2). Methods: We conducted a cross sectional study using 100 samples of archived formalin-fixed paraffin embedded tissue blocks of invasive ductal carcinoma and stained them with immunohistochemistry for PITX2, ER, PR and HER2. All HER2 with scoring of 2+ were confirmed with chromogenic in-situ hybridization (CISH). Results: PITX2 protein was expressed in 53% of invasive ductal carcinoma and lack of PITX2 expression in 47%. Univariate analysis revealed a significant association between PITX2 expression with PR (p=0.001), ER (p=0.006), gland formation (p=0.044) and marginal association with molecular subtypes of breast carcinoma (p=0.051). Combined ER and PR expression with PITX2 was also significantly associated (p=0.003) especially in double positive cases. Multivariate analysis showed the most significant association between PITX2 and PR (RR 4.105, 95% CI 1.765-9.547, p=0.001). Conclusion: PITX2 is another potential prognostic marker in breast carcinoma adding significant information to established prognostic factors of ER and PR. The expression of PITX2 together with PR may carry a very good prognosis.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 C
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• pp.1673-1675
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• 2000

The nonlinearity and degradation characteristics of $Pr_{6}O_{11}$-based ZnO varistors doped with, $Er_{2}O_3$ were investigated. The varistors were sintered at 1335$^{\circ}C$ in the addition range of 0.0 to 2.0 mol% $Er_{2}O_3$, respectively The varistor doped with $Er_{2}O_3$ exhibited more higher nonlinearity than that without $Er_{2}O_3$. Most of the varistors containing 0.5 mol% $Er_{2}O_3$ showed nonlinear exponent more than 70 and a excellent stability, which the variation rate of the varistor voltage and the nonlinear exponent is -0.85% and -1.43%. respectively, even under 3rd d.c stress, such as (0.80 $V_{1mA}/90^{\circ}C$/12h)+(0.85$V_{1mA}/115^{\circ}C$/12h)+(0.90$V_{1mA}/120^{\circ}C$/12h). Consequently, since $Pr_{6}O_{11}$-based 2nO varistors doped with 0.5 mol% $Er_{2}O_3$ have an excellent stability as well as good nonlinearity, it is expected to be usefully used to develop the advanced varistors in future.

• 대한화학회지
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• 제33권6호
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• pp.601-606
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• 1989

Amberite IR 120+양이온 교환수지를 사용하고, 용리액으로 EDTA 용액을 사용하였을 때, 란탄계열원소들($Pr^{3+},\;Nd^{3+},\;Sm^{3+},\;Er^{3+}$)의 분배비와 분리인자에 미치는 온도의 영향과 수지상의 보유이온의 종류에 따르는 영향을 연구하였다. 보유이온들에 있어서는, ${NH_4}^+,\;Na^+,\;K^+,\;Mg^{2+},\;Ca^{2+},\;Zn^{2+}$ 및 $Ce^{3+}$들 중, $Ce^{3+}$이 Nd/Pr의 분리인자를 개선하는데 가장 좋은 효과를 주었으며, $Zn^{2+}$이 Sm/Nd와 Er/Sm이 분리인자를 개선하는데 가장 적당한 보유이온임을 규명하였다. 용리시킬 때 온도의 영향은, 보유이온에 따라 매우 다양하였으며, 온도를 상승시킬 때 분배비는 감소하였다. 그러나 분리인자는 항상 증가하지 않았으며 보유이온이$Ce^{3+}$일 때 온도를 상승시켜 보니, Nd/Pr, Sm/Nd의 분리인자가 증가하였고, 보유이온이 $Zn^{2+}$일 때 온도를 상승시켜 보니 Er/Sm의 분리인자가 증가함을 확인하였다.

• Transactions on Electrical and Electronic Materials
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• 제11권5호
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• pp.216-221
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• 2010

The microstructure, electrical properties, and DC-accelerated aging behavior of the Zn-Pr-Co-Cr-Y-Er (ZPCC-YE) varistors were investigated for different amounts of erbium oxide ($Er_2O_3$). The microstructure consisted of zinc oxide grain and an intergranular layer ($Pr_6O_{11}$, $Y_2O_3$, and $Er_2O_3$-rich phase) as a secondary phase. The increase of $Er_2O_3$ amount decreased the average grain size and increased the sintered density. As the $Er_2O_3$ amount increased, the breakdown field increased from 5094 V/cm to 6966 V/cm and the nonlinear coefficient increased from 27.8 to 45.1. The ZPCC-YE varistors added with 0.5 to 1.0 mol% $Er_2O_3$ are appropriate for high voltage, with high nonlinearity and stability against DC-accelerated aging stress.

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2000년도 춘계총회,특별강연,심포지움,연구발표회
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• pp.79.1-79.1
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• 2000

• 한국전기전자재료학회논문지
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• 제14권5호
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• pp.362-369
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• 2001

The electrical properties of varistors consisting of Zn-Pr-Co-Cr-Er oxides were investigated in the Er$_2$O$_3$content range of 0.0 to 2.0 mol%. the varistors without Er$_2$O$_3$ exhibited a relatively low nonlinearity, which was 14.24 in the nonlinear exponent and 21.47 $\mu$A in the leakage current. However, the varistors with Er$_2$O$_3$ sintered at 1335$^{\circ}C$ for 1h exhibited very high nonlinear exponent of 70, in particular, reaching a maximum value of 78.05 in 2.0 mol% Er$_2$O$_3$, and those sintered at 1335$^{\circ}C$ for 2h exhibited the nonlinear exponent close to 50, in particular, reaching a maximum value of52.76 in 0.5 mol% Er$_2$O$_3$. The others except for 0.5 mol% Er$_2$O$_3$-added varistors exhibited very high instability resulting in a thermal runaway within a short time, even a weak DC stress. Increasing soaking time decreased the nonlinearity, but increased the stability. The varistors containing 0.5mol% Er$_2$O$_3$ sintered for 2h exhibited excellent stability, in which the variation rate of the varistor voltage and nonlinear exponent was -1.70% and -7.15%, respectively, under more severe DC stress such as (0.80 V$_{1mA}$/9$0^{\circ}C$/12h)+(0.85 V$_{1mA}$/115$^{\circ}C$/12h)+(0.90 V$_{1mA}$/12$0^{\circ}C$/12h)+(0.95 V$_{1mA}$/1$25^{\circ}C$/12h)+(0.95 V$_{1mA}$/15$0^{\circ}C$/12h).TEX>/12h).

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 C
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• pp.1003-1007
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• 1999

This paper is reported for the stability of ZnO-$Pr_{6}O_{11}-CoO-Er_{2}O_{3}$ based ceramic varistors with $Er_{2}O_{3}$ added in the addition range 0.0 to 2.0 mol%. The varistors sintered at $130^{\circ}C$ exhibited abrupt positive current creep phenomena, which accompany thermal run away within short times, even under weak d.c. stress. As a result, these varistors were completely degraded. On the contrary, the stability of varistors sintered at $1350^{\circ}C$ was far better than that of $1300^{\circ}C$. In particular, the varistor containing 0.5 mol% $Er_{2}O_{3}$ showed a excellent stability, which the variation rate of the varistor voltage, the nonlinear coefficient, and leakage current is below 1%, 2%, and 3.5%, respectively, even under more severe d.c. stress, such as ($0.8V_{1mA}/90^{\circ}C/12h$) + ($0.85V_{1mA}/115^{\circ}C/12h$) + ($0.9V_{1mA}/120^{\circ}C/12h$) + ($0.9V_{1mA}/150^{\circ}C/12h$). Consequently, it is estimated that the basic composition of ZnO-$Pr_{6}O_{11}-CoO-Er_{2}O_{3}$ based varistor contain 0.5 mol% $Er_{2}O_{3}$ will be used to the fabrication of the varistors for high performance and stability in a forthcoming.

• Asian Pacific Journal of Cancer Prevention
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• 제14권4호
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• pp.2231-2235
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• 2013

Background: Categorizing breast tumors based on the ER, PR and HER/Neu 2 receptor status is necessary in order to predict outcome and assist in management of breast cancer. Herfe we assessed this question in South Indian patients. Materials and Methods: A total of 619 formalin fixed paraffin embedded breast tumor tissues were collected from pathology archives after receipt of ethical clearance. With the help of primary and secondary conjugated antibodies, expression status of ER, PR and HER2/neu was determined. All the experimental data were assessed for correlations with histopathological features of tumors and clinical presentation of the subjects. Results: In the present study, the ages ranged from 20-87 years with a mean of $50.0{\pm}12.q$ years, and majority of the tumors (84%) were of infiltrating duct cell carcinoma type. Assessment of ER, PR and Her-2/neu expression showed that 46% were triple negative. Interestingly, an inverse relation between ER, PR and HER-2/neu was apparent in 41.2% (p<0.0001) of the tumors, of which 24.5% (p<0.0001) were ER and PR co-negative but HER-2 positive. Conclusions: ER and PR positive tumors are less common (i.e<30%) compared to HER-2/neu positive tumors (i.e>50%) in Indian breast cancer patients, underlining the need for effective diagnostic screening and specific therapeutic managements in order to improve the survival rate of patients in low resource countries such as India.