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Jens Breinholt Claus Bekker Jeppesen Sven Branner Carl Erik Olsen Niels Peter Hundahl Mller Bjarne Hilmer Nielsen Henrik Sune Andersen 《Journal of heterocyclic chemistry》2001,38(3):569-577
In DMSO‐solution 2‐amino‐4H‐thiazolo[5,4‐b]indole is converted into a complex mixture of colored products. The three major conversion end‐products, of which two are inhibitors of protein tyrosine phos‐phatases (PTPs), were isolated by chromatographic methods and their structures characterized by spectro‐scopic analysis, including NMR and MS combined with computer assisted structure elucidation, and, finally, confirmed by independent chemical synthesis. Synthesis of 2‐amino‐4H‐thiazolo[5,4‐b]indole as well as its N‐acetyl derivatives prepared from either oxindole or 2‐bromo‐1‐(2‐nitro‐phenyl)ethanone is described. 相似文献
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The lipids ofMaclura aurantiaca seeds have been investigated. The compositions of the neutral and the phosphorus-containing compounds have been determined.This work was presented at the IIIrd International Symposium on the Chemistry of Natural Compounds (Bukhara, Uzbekistan, October 19–22, 1998).Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (371) 120 64 75. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 19–21, January–February, 1999. 相似文献
105.
An affine α-resolvable PBD of index λ is a triple (V, B, R), where V is a set (of points), B is a collection of subsets of V (blocks), and R is a partition of B (resolution), satisfying the following conditions: (i) any two points occur together in λ blocks, (ii) any point occurs in α blocks of each resolution class, and (iii) |B| = |V| + |R| − 1. Those designs embeddable in symmetric designs are described and two infinite series of embeddable designs are constructed. The analog of the Bruck–Ryser–Chowla theorem for affine α-resolvable PBDs is obtained. © 1998 John Wiley & Sons, Inc. J Combin Designs 6:111–129, 1998 相似文献
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How many beds must be allocated to a specific clinical ward to meet production targets? When budgets get tight, what are the effects of downsizing a nursing unit? These questions are often discussed by medical professionals, hospital consultants, and managers. In these discussions the occupancy rate is of great importance and often used as an input parameter. Most hospitals use the same target occupancy rate for all wards, often 85%. Sometimes an exception is made for critical care and intensive care units. In this paper we demonstrate that this equity assumption is unrealistic and that it might result in an excessive number of refused admissions, particularly for smaller units. Queuing theory is used to quantify this impact. We developed a decision support system, based on the Erlang loss model, which can be used to evaluate the current size of nursing units. We validated this model with hospital data over the years 2004–2006. Finally, we demonstrate the efficiency of merging departments. 相似文献
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For capacity planning issues in health care, such as the allocation of hospital beds, the admissions rate of patients is commonly
assumed to be constant over time. In addition to the purely random fluctuations, there is also typically a predictable pattern
in the number of arriving patients. For example, roughly 2/3 of the admitted patients at an Intensive Care Unit arrives during
office hours. Also, most of the scheduled admissions occur during weekdays instead of during the weekend. 相似文献
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Svetlana B. Khrebtova Anna R. Bekker Vitalii K. Belskii Mikhail P. Koroteev Eduard E. Nifantyev 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract Reactions of 3,5-halogenocyclophosphata of 1,2-O-alkylidene-6-desoxy-6-halogeno-α-D-glucofuranoses with water, alcohols, and amines were studied, which permit the obtaining of corresponding 3,5-cyclophosphates, their salts, and amides: 相似文献