• 제목/요약/키워드: Gupta

검색결과 631건 처리시간 0.031초

Effect of Lymphangiogenesis and Lymphovascular Invasion on the Survival Pattern of Breast Cancer Patients

  • Sahoo, Pradyumna Kumar;Jana, Debarshi;Mandal, Palash Kumar;Basak, Samindranath
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권15호
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    • pp.6287-6293
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    • 2014
  • Background: Invasion of breast cancer cells into blood and lymphatic vessels is one of the most important steps for metastasis. In this study the prognostic relevance of lymphangiogenesis and lymphovascular invasion (LVI) in breast cancer patients was evaluated in terms of survival. Materials and Methods: This retrospective study concerned 518 breast cancer patients who were treated at Department of Surgical Oncology, Saroj Gupta Cancer Centre and Research Institute, Kolkata-700063, West Bengal, India, a reputed cancer centre and research institute of eastern India between January 2006 and December 2007. Results: The median overall survival and disease free survival of the patients were 60 months and 54 months respectively. As per Log-rank test, poor overall as well as disease free survival pattern was observed for LVI positive patients as compared with LVI negative patients (p<0.01). Also poor overall as well as disease free survival pattern was observed for perineural invasion (PNI) positive patients as compared to PNI negative patients (p<0.01). Conclusions: From this study it is evident that LVI and PNI are strongly associated with outcome in terms of disease free as well as overall survival in breast cancer patients. Thus LVI and PNI constitute potential targets for treatment of breast cancer patients. We advocate incorporating their status into breast cancer staging systems.

Metal Insulator Gate Geometric HEMT: Novel Attributes and Design Consideration for High Speed Analog Applications

  • Gupta, Ritesh;Kaur, Ravneet;Aggarwal, Sandeep Kr;Gupta, Mridula;Gupta, R.S.
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제10권1호
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    • pp.66-77
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    • 2010
  • Improvement in breakdown voltage ($BV_{ds}$) and speed of the device are the key issues among the researchers for enhancing the performance of HEMT. Increased speed of the device aspires for shortened gate length ($L_g$), but due to lithographic limitation, shortening $L_g$ below sub-micrometer requires the inclusion of various metal-insulator geometries like T-gate onto the conventional architecture. It has been observed that the speed of the device can be enhanced by minimizing the effect of upper gate electrode on device characteristics, whereas increase in the $BV_{ds}$ of the device can be achieved by considering the finite effect of the upper gate electrode. Further, improvement in $BV_{ds}$ can be obtained by applying field plates, especially at the drain side. The important parameters affecting $BV_{ds}$ and cut-off frequency ($f_T$) of the device are the length, thickness, position and shape of metal-insulator geometry. In this context, intensive simulation work with analytical analysis has been carried out to study the effect of variation in length, thickness and position of the insulator under the gate for various metal-insulator gate geometries like T-gate, $\Gamma$-gate, Step-gate etc., to anticipate superior device performance in conventional HEMT structure.