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1.
This paper commences with a brief introduction to modern techniques for the computational analysis of molecular diversity and the design of combinatorial libraries. It then reviews dissimilarity-based algorithms for the selection of structurally diverse sets of compounds in chemical databases. Procedures are described for selecting a diverse subset of an entire database, and for selecting diverse combinatorial libraries using both reagent-based and product-based selection.  相似文献   
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Using a high-performance liquid chromatographic procedure, age- and gender-based reference ranges for plasma retinol, alpha- and gamma-tocopherol, lycopene, and alpha- and beta-carotene have been established. In addition to confirming higher retinol levels in men than in women (p less than 0.001), this study demonstrates significantly higher plasma levels of both carotenes in women than in men (p less than 0.001). The plasma levels of retinol and beta-carotene showed a positive relationship with age after adjusting for plasma lipids (p less than 0.001 and p less than 0.02, respectively). In contrast to beta-carotene, there was no gender difference for plasma lycopene and a strong (p less than 0.001) inverse relationship of lycopene with age. These results suggest that differences may exist between beta-carotene and lycopene in their intestinal absorption, plasma transport, or tissue metabolism.  相似文献   
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Using 3-D searching techniques based on algorithms derived from graph theory we have established a striking structural similarity between the structure of bovine carboxypeptidase A and that of the C-terminal domain of bovine leucine aminopeptidase. There is no significant sequence homology between the aminopeptidases and the carboxypeptidases but the strong structural relationship detected in this complex fold suggests that there may be a very remote divergent evolutionary relationship between these two enzyme classes.  相似文献   
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Report is made of the first primary cytodiagnosis of a synchronous small-cell cancer of the lung and squamous-cell carcinoma of the larynx, which were histologically confirmed. Sputum cytology should be used in the detection and surveillance of multiple primary malignancies of the respiratory tract, which have been observed with increasing frequency.  相似文献   
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Onion maggot (Delia antiqua) is an economically important pest of Allium crops in temperate regions throughout the world. Management of this pest is necessary to achieve economic returns and depends on insecticide regimes and cultural management. Current cultural management especially altering planting date, field location and crop rotation depend on monitoring. We evaluated the effect of shape, size, colour and chemical attractants on trap catch of field populations of adult D. antiqua flies in upstate New York. White, large diameter, spherical traps in conjunction with Delia Lure attractant performed the best in attracting and catching D. antiqua adults. These results suggest an improved means of attracting and capturing D. antiqua populations which could be useful in monitoring efforts and development of attract and kill strategies for pest control.  相似文献   
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The central organelle within the secretory pathway is the Golgi apparatus, a collection of flattened membranes organized into stacks. The cisternal maturation model of intra-Golgi transport depicts Golgi cisternae that mature from cis to medial to trans by receiving resident proteins, such as glycosylation enzymes via retrograde vesicle-mediated recycling. The conserved oligomeric Golgi (COG) complex, a multi-subunit tethering complex of the complexes associated with tethering containing helical rods family, organizes vesicle targeting during intra-Golgi retrograde transport. The COG complex, both physically and functionally, interacts with all classes of molecules maintaining intra-Golgi trafficking, namely SNAREs, SNARE-interacting proteins, Rabs, coiled-coil tethers, vesicular coats, and molecular motors. In this report, we will review the current state of the COG interactome and analyze possible scenarios for the molecular mechanism of the COG orchestrated vesicle targeting, which plays a central role in maintaining glycosylation homeostasis in all eukaryotic cells.  相似文献   
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One hundred and two conformations of alpha- and beta-D-allopyranose, the C-3 substituted epimer of glucopyranose, were geometry optimized using the density functional, B3LYP, and the basis set, 6-311++G **. Full geometry optimization was performed on different ring geometries and on the hydroxymethyl rotamers (gg/gt/tg). Analytically derived Hessians were used to calculate zero point energy, enthalpy, and entropy. The lowest energy and free energy conformation found is the alpha-tg(g-)-4C1-c conformation, which is only slightly higher in electronic (approximately 0.2 kcal/mol) and free energy than the lowest energy alpha-D-glucopyranose. The in vacuo calculations showed a small (approximately 0.3 kcal/mol) energetic preference for the alpha- over the beta-anomer for allopyranose in the 4C1 conformation, whereas in the 1C4 conformation a considerable (approximately 1.6 kcal/mol) energetic preference for the beta- over the alpha-anomer for allopyranose was encountered. The results are compared to previous aldohexose calculations in vacuo. Boat and skew forms were found that remained stable upon gradient optimization although many starting boat conformations moved to other skew forms upon optimization. As found for glucose, mannose, and galactose the orientation and interaction of the hydroxyl groups make the most significant contributions to the conformation/energy relationship in vacuo. A comparison of different basis sets and density functionals is made in the Discussion section, confirming the appropriateness of the level of theory used here.  相似文献   
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