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991.
Trimethylaminuria, also called fish-odour syndrome, is an inherited disorder caused by deficient N-oxidation and increased excretion of trimethylamine. This study reports on two unrelated and otherwise healthy children with transient trimethylaminuria, a hitherto unknown abnormality, without N-oxidation deficiency. This demonstrates that a diagnosis of fish-odour syndrome should include the analysis of urinary excretion not only of trimethylamine but also of trimethylamine-N-oxide. Since transient trimethylaminuria may be a common condition and no cause for it can presently be recognized, such patients will require careful follow-up. 相似文献
992.
993.
Improvement of power supply EMC by chaos 总被引:12,自引:0,他引:12
The authors demonstrate the feasibility of using chaos to depress the spectral peaks of the interference from a switched mode power supply. A boost converter is used to show experimentally that the spectrum of the input current is spread, its peaks are reduced and EMC is improved, compared to the case when the circuit is operating periodically 相似文献
994.
A simple extension to the staircase FDTD algorithm yielding accurate subcell models of flat metal walls and corners is presented. Electric field nodes on the edges of staircase models of perfect electric conductors are replaced by values obtained using interpolation or analytic continuation into the metal. The algorithm is validated by computing the resonant frequencies of cavities 相似文献
995.
L. D. Panteleev L. N. Konovalov I. I. Konovalov S. A. Krylov V. B. Malygin K. I. Naboichenko 《Atomic Energy》1994,77(2):613-617
A. A. Bochvar All-Union Scientific-Research Institute of Standardization in Machine Engineering. Moscow Engineering Physics
Institute. Translated from Atomnaya énergiya, Vol. 77, No. 2, pp. 123–129, August, 1994. 相似文献
996.
This paper describes a verified compiler for PreScheme, the implementation language for thevlisp run-time system. The compiler and proof were divided into three parts: A transformational front end that translates source text into a core language, a syntax-directed compiler that translates the core language into a combinator-based tree-manipulation language, and a linearizer that translates combinator code into code for an abstract stored-program machine with linear memory for both data and code. This factorization enabled different proof techniques to be used for the different phases of the compiler, and also allowed the generation of good code. Finally, the whole process was made possible by carefully defining the semantics ofvlisp PreScheme rather than just adopting Scheme's. We believe that the architecture of the compiler and its correctness proof can easily be applied to compilers for languages other than PreScheme.This work was supported by Rome Laboratory of the United States Air Force, contract No. F19628-89-C-0001, through the MITRE Corporation, and by NSF and DARPA under NSF grants CCR-9002253 and CCR-9014603. Author's current address: Department of Computer Science and Engineering, Oregon Graduate Institute, P.O. Box 91000, Portland, OR 97291-1000.The work reported here was supported by Rome Laboratory of the United States Air Force, contract No. F19628-89-C-0001. Preparation of this paper was generously supported by The MITRE Corporation.This work was supported by Rome Laboratory of the United States Air Force, contract No. F19628-89-C-0001, through the MITRE Corporation, and by NSF and DARPA under NSF grants CCR-9002253 and CCR-9014603. 相似文献
997.
998.
An overview of MOSFET modeling for circuit simulation is presented. After discussing some of the implications of analog and low-power applications, the history of the MOS models commonly used in SPICE-like circuit simulators is presented, followed by a discussion of the evolution of strategies for modeling the geometry dependence of MOSFET characteristics. The growth of complexity and requirements for future MOS models are also considered 相似文献
999.
D Del Bufalo C Cucco C Leonetti G Citro I D'Agnano M Benassi T Geiser G Zon B Calabretta G Zupi 《Canadian Metallurgical Quarterly》1996,74(3):387-393
We investigated the effect of c-myb antisense phosphorothioate oligodeoxynucleotides [(S)ODNs] and cisplatin (CDDP) combination on the human colon carcinoma cell line LoVo Dx both in vitro and in nude mice bearing LoVo Dx solid tumour. We show that antisense (S)ODN treatment decreases c-myb mRNA and protein expression, induces growth arrest in the G1 phase of the cell cycle, and inhibits cell proliferation. In vivo treatment with c-myb antisense (S)ODNs results in a reduction in tumour growth. A greater inhibition of cell proliferation in vitro and a higher increase of tumour growth inhibition and growth delay in vivo were obtained with the combination of (S)ODNs and CDDP than when the two agents were administered separately. This comparative study, using the same tumour cell line in vitro and in vivo, suggests that c-myb antisense (S)ODNs might be useful in the therapy of colon cancer in combination with antineoplastic drugs. 相似文献
1000.
V. P. Ryabukho V. L. Khomutov D. V. Lyakin K. V. Konstantinov 《Technical Physics Letters》1998,24(2):132-134
Analogies with interferometers using a light source with low temporal coherence are used to analyze the principles of the
construction of laser interferometers with averaging over the photodetector aperture, whose sensitivity to the position of
an object being monitored at the maximum of the output signal is as good as that of low-coherence interferometry and tomography.
Pis’ma Zh. Tekh. Fiz. 24, 19–24 (February 26, 1998) 相似文献