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931.
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A series of novel, highly potent alpha(v)beta(3) antagonists based on a thiophene scaffold and containing an acylguanidine as an Arg-mimetic is described. A number of structural features, such as cyclic versus open guanidine and a variety of lipophilic side chains, carbamates, sulfonamides and beta-amino acids were explored with respect to inhibition of alpha(v)beta(3) mediated cell adhesion and selectivity versus alpha(IIb)beta(3) binding. In addition, compound 19 was found to be active in the TPTX model of osteoporosis.  相似文献   
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By using a picrosirius dye, sensitive and specific staining of collagens plated in microtiter wells was achieved. The range of detection was from 0.5 to 20 micrograms. Human collagen types I, III, IV, and V were tested and able to be detected by the method. The dye did not bind to acetylcholinesterase or elastin. It did bind to C1q to some extent but this is not surprising since the molecule contains some triple helical collagen-like structures. A comparison performed between this assay and a colorimetric assay for hydroxyproline using tissue culture supernatants gave similar results for both samples. Due to its simplicity and sensitivity this assay will be most useful in laboratories where large numbers of samples must be screened for collagen production.  相似文献   
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An F2 resource population, derived from a broiler × layer cross, was used to map quantitative trait loci (QTL) for body weights at days 1, 35 and 41, weight gain, feed intake, feed efficiency from 35 to 41 days and intestinal length. Up to 577 F2 chickens were genotyped with 103 genetic markers covering 21 linkage groups. A preliminary QTL mapping report using this same population focused exclusively on GGA1. Regression methods were applied to line-cross and half-sib models for QTL interval mapping. Under the line-cross model, eight QTL were detected for body weight at 35 days (GGA2, 3 and 4), body weight at 41 days (GGA2, 3, 4 and 10) and intestine length (GGA4). Under the half-sib model, using sire as common parent, five QTL were detected for body weight at day 1 (GGA3 and 18), body weight at 35 days (GGA2 and 3) and body weight at 41 days (GGA3). When dam was used as common parent, seven QTL were mapped for body weight at day 1 (GGA2), body weight at day 35 (GGA2, 3 and 4) and body weight at day 41 (GGA2, 3 and 4). Growth differences in chicken lines appear to be controlled by a chronological change in a limited number of chromosomal regions.  相似文献   
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