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排序方式: 共有8800条查询结果,搜索用时 15 毫秒
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Patel Sapna Kumar Dushyant Chaurasiya Nitesh Kumar Tripathi Shweta 《Semiconductors》2019,53(13):1797-1803
Semiconductors - In the present paper, analytical modeling of surface potential and drain current for hetero-dielectric double gate tunnel FET (HDG-TFET) has been done. The two dimensional (2D)... 相似文献
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Journal of Mechanical Science and Technology - An experimental study is performed to explore the effect of swirl and number of swirler vanes on combustion characteristics of methane inverse... 相似文献
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Parsania P. H. Sankhavara Dharmesh B. Chopda Jalpa Patel Jignesh P. 《Polymer Bulletin》2020,77(6):3111-3128
Polymer Bulletin - Jute and glass composites of epoxy resin of (2E, 6E)-bis(4-hydroxybenzylidene)cyclohexanone (EBHBC) were prepared by compressing molding technique using three different hardeners... 相似文献
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全流程低功耗设计技术的应用 总被引:1,自引:0,他引:1
SameerPatel 《电子设计应用》2004,(1):91-92
随着便携式电子设备的日益使用,要求集成电路IC及SoC的功耗越来越低。在今后日益复杂的设计中,实现一个可靠的电源网络以减小功耗变成了主要的挑战。对于使用者来说,期待每一代新产品都具有新型功能,同时也希望产品的体积小并具有较长的工作时间。解决这个难题的方法之一就是采用新型的IC设计技术,以提供小而且高效的晶体管。在整个设计流程中,为了使器件的性能和可靠性最优,电源方面的限制非常关键。例如在逻辑门应用中,由于开关从一种状态转换到另一种状态从而引起动态功耗。在开关的转换过程中,和晶体管门极相连的所有内部电容将会被… 相似文献
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IC Wilson TJ Gardner JM DiNatale AM Gillinov WE Curtis DE Cameron 《Canadian Metallurgical Quarterly》1993,106(5):805-810
Leukocyte depletion improves early postischemic ventricular performance in neonatal models of global myocardial ischemia. However, the rate of leukocyte reaccumulation after cardiopulmonary bypass and its subsequent impact on myocardial function is not known. This laboratory study examined the effect of leukocyte depletion on myocardial performance during the initial 6-hour period after bypass in an in situ, in vivo porcine model of neonatal cardiac surgery. Fifteen 3- to 5-day-old piglets (eight control and seven leukocyte depleted animals) were instrumented by placement of left ventricular short-axis sonomicrometry crystals and an intraventricular micromanometer catheter. Mechanical leukocyte depletion was achieved with Pall RC100 filters (Pall Biomedical, Inc., Fajardo, Puerto Rico) in the cardiopulmonary bypass circuit. Neonatal hearts were subjected to 90 minutes of hypothermic ischemia after a single dose of cold crystalloid cardioplegia. Two control animals died after the operation and were excluded from data analysis. Leukocyte filtration reduced the granulocyte count during initial myocardial reperfusion to 0.8% of control values. However, circulating granulocyte counts increased in leukocyte depleted animals throughout the postoperative period, reaching 68% of control values by 6 hours. Despite this rapid return of circulating granulocytes, animals subjected to leukocyte depletion had significantly better preservation of left ventricular performance (measured by preload recruitable stroke work, p < or = 0.02), left ventricular systolic function (measured by end-systolic pressure-volume relationship, p < or = 0.05), and ventricular compliance (p < or = 0.04) during the experiment. These changes in ventricular function were associated with a significant increase in left ventricular water content (p < or = 0.02) and tissue myeloperoxidase activity (p < or = 0.005) in control animals compared with leukocyte depleted animals. This study demonstrates that leukocyte depletion during initial reperfusion results in sustained improvement in postischemic left ventricular function despite the rapid return of granulocytes to the circulation. 相似文献
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GA Masters AM Mauer PC Hoffman D Wyka BL Samuels SA Krauss S Watson H Golomb EE Vokes 《Canadian Metallurgical Quarterly》1998,9(6):677-680
PURPOSE: We designed a phase I-II trial of three active agents, paclitaxel, ifosfamide, and vinorelbine, in advanced non-small-cell lung cancer (NSCLC) to: 1) define the dose-limiting toxicities (DLT) and maximum tolerated dose (MTD) of paclitaxel with filgrastim (G-CSF) support; and 2) determine the overall response rate and median survival of patients treated on this regimen. PATIENTS AND METHODS: We treated cohorts of patients with stage IIIB or IV NSCLC with ifosfamide 1.2-1.6 g/m2/day x 3 and vinorelbine 20-25 mg/m2/day x 3 and escalating doses of paclitaxel at 100-175 mg/m2 on day 2 with G-CSF support on a 21-day cycle. One prior experimental single-agent chemotherapy regimen was allowed. RESULTS: Fifty-six patients, were enrolled on this trial: 27 on the phase I portion of the study and an additional 29 at the recommended phase II dose (RPTD). Thirteen patients had received prior chemotherapy. Paclitaxel doses of 175 mg/m2 and 150 mg/m2 produced dose-limiting myelosuppression, and the RPTD was determined to be paclitaxel 135 mg/m2 with ifosfamide 1.2 g/m2/day on days 1-3 and vinorelbine 20 mg/m2/ day on days 1-3 with G-CSF support. The overall response rate was 18%, with a median survival of 6.1 months. Six of 35 patients (17%) treated at the RPTD achieved a partial response to therapy. Grade IV neutropenia was observed in 19 of 35 patients at this dose, with eight patients suffering febrile neutropenia. CONCLUSIONS: This non-cisplatin-containing three-drug regimen has substantial toxicity and low activity in advanced NSCLC, and does not seem to improve on prior regimens. It is unclear whether the lack of efficacy relates to an antagonistic reaction between the specific drugs, administration schedule, or to subtherapeutic doses of the individual agents. 相似文献
10.
Synapse elimination in the central nervous system: functional significance and cellular mechanisms 总被引:1,自引:0,他引:1
Recent research into the developmental elimination of supernumerary synapses has increased understanding of this process. In this review we discuss synapse elimination both at the neuromuscular junction and in the central nervous system, considering some possible underlying mechanisms suggested by recent studies. In addition a well-described example of central nervous system synapse elimination, the climbing fiber-Purkinje cell synapse of the cerebellum, is used to explore the functional significance of synaptic regression during brain development. 相似文献