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71.
Jeff Sherman 《电子与电脑》2010,(11):56-58
硅芯片(silicon)及封装技术的进展使得尺寸缩小的产品需要更多的电量,DualCoolTM NexFETTM电源MOSFET结合新一代硅产品技术与能够在标准体积尺寸中达到上端降温(topside cooling)效果的封装,这些技术的结合使得效率、功率密度(power density)及可靠度达到新境界,本文将着重在效能优点方面说明这些新技术。 相似文献
72.
McKay MJ Sherman J Laver MT Baker MS Clarke SJ Molloy MP 《Proteomics. Clinical applications》2007,1(12):1570-1581
There is wide interpatient variability in toxicity to chemotherapeutic drugs and a lack of routine clinical tests for prospectively identifying patients at risk of developing toxicity from chemotherapy. An empirically driven MS strategy has been developed to monitor liver-derived plasma proteins as potential biomarkers of early toxicity. Multiple reaction monitoring (MRM) has been used to assess 46 candidate peptides from 18 liver-derived proteins. Following an iterative process of assay design, optimisation and assessment we selected 29 MRM assays (median CV 4.6%, range 1.2-11.6%) and monitored changes in levels of plasma proteins from a small number of colorectal cancer (CRC) patients undergoing chemotherapy. We demonstrated MRM assay robustness, and show that patients undergo minor elevation in plasma proteins when profiled on Day 3 of the chemotherapeutic regime. The MRM assays were in general agreement with 2-D DIGE-based quantitation from the same patient samples. The data supports the application of MRM-based methods as facile, highly reproducible, medium-throughput techniques that warrant expanded investigation for clinical utility in identifying patients at risk of developing chemotoxicity. 相似文献
73.
Electrostatic fields of macromolecules (e.g., protein molecules) in solvents are often described by the Poisson-Boltzmann equation. This paper introduces two substantial amendments to the electrostatic model: first, the effective dielectric permittivity of the aqueous solvent layer on the molecular surface is drastically different from its bulk value of ~80 and, second, the recently developed flexible local approximation methods produce different schemes with much higher accuracy than the classical ones 相似文献
74.
75.
David Sherman 《Cryptologia》2017,41(3):195-238
In addition to being one of the founders of modern American cryptology, William Friedman was a noted cryptologic historian who amassed a major collection of cryptologic literature and artifacts in both his personal and official files. Drawing on over 50,000 pages of documents newly released by the National Security Agency and other sources, this article places the man, his career, and his collections in the context of the government's changing secrecy policies of the early Cold War to offer new insights into Friedman's sometimes fraught relationship with that agency, its efforts to influence the amount and nature of cryptologic information in the public domain, and a series of confrontations over his personal and private papers. 相似文献
76.
K.M. Chen and V. Liepa (IEEE Trans. Antennas Propag., p.576-82, September 1964) described the broadside backscatter of a thin dipole. The model is summarized by various. These work very well at all frequencies specified by those authors, except for one-physical resonance. This is the wavelength at which the antenna's total length is half a wavelength. The present author develops an alternate set of equations which are valid at resonance 相似文献
77.
78.
Fusion proteins constructed of a tumor-specific Ab joined to IL-2 (Ab-IL-2) have been used in the past to deliver cytokine directly to the site of tumor cells in vivo. These molecules mimic the activity of IL-2 and assist in activating and expanding antitumor effector cells. To enhance the cytolytic activity of CTL specific for peptide epitopes of the Her-2/neu tumor Ag presented by HLA-A*0201 molecules, a fusion protein was constructed consisting of a single chain Ab specific for Her-2/neu, linked to IL-2 (neu-Ab-IL-2). When added to a mixture of tumor cells and Her-2/neu-specific CTL, the protein was found to augment lysis of tumor cells. In addition, the hybrid molecule also promoted lysis of Her-2/neu expressing tumors by non-tumor-specific cloned T cell lines, including Th1 CD4 cells. Analysis of the mechanism of cytotoxicity revealed that the fusion protein mediates the formation of stable conjugates between T cells expressing IL-2R and tumor cells expressing Her-2/neu, resulting in lysis through the Fas-Fas ligand pathway. Lysis induction was independent of specific engagement by the TCR. When tested for its ability to enhance tumor cell eradication by Her-2/neu-specific CD8+ T cells in an adoptive transfer model in SCID mice, neu-Ab-IL-2 facilitated the elimination of tumor cells in vivo. Surprisingly, the combination of non-tumor-specific CD8+ T cells and fusion protein also induced a significant delay of tumor growth. This represents a novel approach for redirecting non-tumor-specific T cells to eliminate tumors. 相似文献
79.
As patients with HIV/AIDS are living longer with the illness, pain and symptom management are increasingly important health issues. This article will discuss the assessment and management of such common problems as pain, fatigue and weakness, dyspnea and cough, anorexia and weight-loss, nausea and vomiting, sleep disorders, dry mouth, diarrhea, itching, and fever and night sweats. 相似文献
80.
To study the dietetic effect of canned natural Ivasi herring, containing up to 10% of eicosopentenic acid, the blood serum was analyzed in 37 patients with coronary heart disease at Vladivostok City Hospital and in 73 patients at the Regional Cardiological Sanatorium. Lipid characteristics of the blood serum (total cholesterol, alpha- and beta-cholesterol, beta-lipoproteins) were comparatively studied in 5 groups of subjects: normal subjects, two control groups (who did not receive the dietetic product) and two groups who received Ivasi herring. A favourable effect on all above parameters was recorded in more than 50% of patients in the sanatorium. The frequency of favourable shifts was higher in patients who received Ivasi herring than in the controls, the highest changes concerned beta-cholesterol. No significant improvement was recorded in coronary patients during the acute period (the group at the City Hospital). The results of the investigation have evidenced the expediency of using canned Ivasi herring in the diet therapy and prevention of coronary heart disease during the rehabilitation period. 相似文献