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1.
图形点阵式液晶显示器MSP-G320240在高速处理器DSP中的应用 总被引:1,自引:1,他引:0
介绍了内置SD1335控制器的图形液晶显示器MSP-G320240的工作原理及应用方法,给出了MSP-G320240液晶显示器同DSP的简单接口电路,同时给出了相应的液晶显示器的初始化和清显示区的具体程序。 相似文献
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MA Nowak AL Lloyd GM Vasquez TA Wiltrout LM Wahl N Bischofberger J Williams A Kinter AS Fauci VM Hirsch JD Lifson 《Canadian Metallurgical Quarterly》1997,71(10):7518-7525
Mathematical modeling of viral replication dynamics, based on sequential measurements of levels of virion-associated RNA in plasma during antiretroviral treatment, has led to fundamental new insights into human immunodeficiency virus type 1 pathogenesis. We took advantage of the simian immunodeficiency virus (SIV)-infected macaque model to perform detailed measurements and mathematical modeling during primary infection and during treatment of established infection with the antiretroviral drug (R)-9-(2-phosphonylmethoxypropyl)adenine (PMPA). The calculated clearance half-life for productively infected cells during resolution of the peak viremia of primary infection was on the order of 1 day, with slightly shorter clearance half-lives calculated during PMPA treatment. Viral reproduction rates upon discontinuation of PMPA treatment after 2 weeks were approximately twofold greater than those obtained just prior to initiation of treatment in the same animals, likely reflecting accumulation of susceptible target cells during treatment. The basic reproductive ratio (R0) for the spread of SIV infection in vivo, which represents the number of productively infected cells derived from each productively infected cell at the beginning of infection, was also estimated. This parameter quantifies the extent to which antiviral therapy or vaccination must limit the initial spread of virus to prevent establishment of chronic disseminated infection. The results thus provide an important guide for efforts to develop vaccines against SIV and, by extension, human immunodeficiency virus. 相似文献
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Comparison evaluation of the methods of treatment was based on the analysis of the results of management of 347 patients with general purulent decompensated peritonitis with polyorganic insufficiency. The efficacy of closed drainage in 98 patients, continuous flow irrigation (dialysis) in 126, stage programmed irrigation and inspection of the abdominal cavity in 99, and open drainage in 24 patients was compared. The causes of peritonitis were: complications after acute surgical diseases (in 156 cases), in planned operations (59), and in obstetrical and gynecological diseases (132). Most of the patients were brought to the clinic from other hospitals because of unsuccessful treatment of peritonitis and absence of means for performing hemodialysis and management of polyorganic insufficiency. The incidence of the last-named reached 71.0 to 91.0% in the different groups of patients. In monotypic complex treatment, stage programmed irrigation was marked by a much lesser number of abscesses and other complications and a lower mortality (20.2%) as compared to flow irrigation (30.0%, closed drainage (27.5%), and open (laparostomy) treatment (37.5%). Despite the very serious contingent of patients, total mortality (27.0%) in the application of the indicated methods was quite low. 相似文献
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In this paper we propose a multiobjective decision making based neural-network model and algorithm for image reconstruction from projections. This model combines the Hopfield's model and multiobjective decision making approach. We develop a weighted sum optimization based neural-network algorithm. The dynamical process of the net is based on minimization of a weighted sum energy function and Euler's iteration, and apply this algorithm to image reconstruction from computer-generated noisy projections and Siemens Somatson DR scanner data, respectively. Reconstructions based on this method is shown to be superior to conventional iterative reconstruction algorithms such as the multiplicate algebraic reconstruction technique (MART) and convolution from the point of view of accuracy of reconstruction. Computer simulation using the multiobjective method shows a significant improvement in image quality and convergence behavior over the conventional algorithms 相似文献
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In this study we have employed the whole cell patch clamp technique to investigate the effects of an anti-cancer drug cisplatin on basic electrophysiological properties of cultured dorsal root ganglion neurones from neonatal rats. The results show that within the clinical concentration range, cisplatin (0.1 to 10 microM) caused a decrease in input conductance, and complex changes in resting membrane potential in these cultured sensory neurones. The dominant effects of cisplatin on input conductance may be due to inhibition of leak conductances. Transplatin (5 microM) was significantly less effective than cisplatin at reducing input conductance which suggests a degree of stereoselectivity. Cisplatin (1 to 5 microM) transiently increased excitability of the cultured neurones as reflected by a reduction in the threshold for activation of action potentials by 8 mV. The rise time, peak amplitude and duration of action potentials were not changed by acute application of 5 microM cisplatin. Long term treatment of neurones with cisplatin (5 microM), for up to 1 week reduced the viability of the cultures, and attenuated neurone excitability, although input conductance of the cells was significantly increased to 322 +/- 49 M omega (n = 9) compared with controls of 210 +/- 20 M omega (n = 30; P < 0.05). Acute and chronic treatment of cultured neurones with cisplatin therefore produced contrasting actions. 相似文献