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功能看点:65536色TFT液晶屏、64和弦铃声、CCD型摄像头、有声视频拍摄(10秒/段,3GPP格式)、红外、录音(30秒/段,可设置为铃声)、全屏来电大头贴等。 相似文献
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Kane B.C. Geis L.A. Wyatt M.A. Copeland D.G. Mogensen J.A. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》2005,93(9):1656-1668
As BiCMOS IC technology continues to advance in scaling and performance, new applications are continually enabled. One such concept is a smart phased array system on a chip (SoC). The combination of high-performance SiGe heterojunction bipolar transistor (HBT) bipolar devices, well-characterized RF/analog passive components, and dense CMOS digital technology provides the capability to create large multielement, electronically tunable phased arrays with onboard processing intelligence, inside a single die. This SoC will have superior characteristics of lower cost, weight, and size as compared to the large multichip, multitechnology, and multipackage systems in deployment today. Furthermore, using reconfigurable logic and embedded memory, this SoC has the advantage of dynamic software and digital signal processing engine updates, without expensive redesigns of the chip. This publication will describe the necessary ingredients to create such an SoC as well as relevant applications of smart phased arrays that require an SiGe HBT BiCMOS technology. Potential markets for this technology include communications systems, weather tracking, radio astronomy, automotive radar, cellular basestation capacity improvement, satellite and aerial resource imaging, ground-level airplane collision avoidance, as well as military tracking and guidance systems. 相似文献
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The importance of the expression of the autocrine growth system for bombesin-like peptides (BLPS) to the biological behavior of human lung cancer has not been determined. Three BLP receptor subtypes have been identified in human lung and lung cancer cells: gastrin-releasing peptide (GRP) receptor, neuromedin B (NMB) receptor, and bombesin receptor subtype 3 (BRS-3). The goals of this study were: (1) to determine BLP receptor subtype expression by human lung cancer cell lines by RT/PCR; (2) to evaluate possible clinical correlates of characteristics of the patients from whom the cell lines were derived with patterns of BLP receptor expression. Degenerate PCR primers were designed to amplify all known BLP receptors and yielded products from 19/20 small cell lung carcinoma (SCLC) and 12/13 non-small cell lung carcinoma (NSCLC) cell lines. GRP receptor was the most commonly expressed BLP receptor subtype, being detected in 17/20 SCLC and 11/13 NSCLC. Eleven of 20 SCLC expressed NMB receptors, and 5/20 expressed BRS-3, compared with 4/13 and 1/13, respectively, in NSCLC cell lines. Evaluation of the clinical data of the patients from whom the cell lines were derived revealed expected age, sex, smoking history and survival based on histology and stage. Patients from whom cell lines expressed GRP receptor experienced a better survival than those whose cell lines did not (367 +/- 274 days vs. 211 +/- 114 days), but the results were not statistically significant. RT/PCR analysis is a feasible, sensitive and specific means of determining BLP receptor expression in lung cancer cells and may yield prognostic information in patient tissue. 相似文献
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Recent advances in epitaxial growth have led to the prospect of artificial modification of the electronic structure or band structure of semiconductor materials. The combination of strain and quantum confinement in the valence band can lead to substantially more favorable energy dispersion relations for laser action than those existing in the natural semiconductor crystal. Numerical results are presented for a series of alloy compositions with a bandgap near the 1.55-μm optimum wavelength for optical communications. The laser threshold current and the intervalence band absorption can be significantly diminished in properly engineered band structures 相似文献
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Metallurgical and Materials Transactions A - 相似文献
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Somatic cell cloned transgenic bovine neurons for transplantation in parkinsonian rats 总被引:1,自引:0,他引:1
WM Zawada JB Cibelli PK Choi ED Clarkson PJ Golueke SE Witta KP Bell J Kane FA Ponce de Leon DJ Jerry JM Robl CR Freed SL Stice 《Canadian Metallurgical Quarterly》1998,4(5):569-574
OBJECTIVE: To identify consistent relevant mechanisms of small intestinal dysfunction in cats with experimentally induced feline immunodeficiency virus infection (FIV) that developed chronic diarrhea during the time they were being used in studies of pathogenicity and transmission of FIV. ANIMALS: 10 cats. PROCEDURE: The following investigative tests and techniques were performed on each of the cats: routine hematologic and serum biochemical analyses; urinalysis; fecal parasitologic and microbiologic examinations; breath hydrogen lactulose (BH2LT) and xylose (BH2XT) tests; intestinal permeability test; endoscopic examination of the intestinal mucosa; bacteriologic culture of endoscopically collected small intestinal juice; and histologic examination of endoscopically obtained intestinal biopsy specimens. RESULTS: Neutrophilia was evident in 3 cats, and lymphopenia was detected in 2 cats. Serum biochemical abnormalities were not observed. Urinalysis results were unremarkable. Fecal bacteriologic and parasitologic results were normal, except for isolation of Campylobacter sp from 1 cat. Abnormal BH2XT values suggestive of D-xylose malabsorption were identified in 2 cats, and BH2LT values indicated evidence of small intestinal bacterial overgrowth in 1 cat. Finally, permeability test results, quantitation of bacterial flora from the proximal part of the small intestine and histologic examination of biopsy specimens did not reveal any abnormalities. CONCLUSIONS: Enteric pathogens did not account for the development of diarrhea in cats with experimentally induced FIV infection, and consistent relevant mechanisms of small intestinal dysfunction were not identified. 相似文献
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In 2 experiments with a total of 140 undergraduates, Ss who completed the last words of sentences they read learned more than Ss who simply read whole sentences. This facilitation was observed even with sentences that were almost always completed with the wrong words. However, proactive interference attributable to acquisition errors appeared on recall and recognition tests administered after a 1-wk interval. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献