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101.
OBJECTIVE--To evaluate the prognostic factors in uncomplicated venous leg ulcer healing. DESIGN--Randomised parallel group controlled trial with subjects stratified by initial ulcer diameter and four months'' maximum duration of follow up. SETTING--Assessment at Northwick Park Hospital vascular unit with community based treatment. PATIENTS--200 patients with clinical and objective evidence of uncomplicated venous leg ulceration and an initial ulcer diameter > 2 cm. MAIN OUTCOME MEASURE--Time to complete healing of the ulcer. RESULTS--In the presence of graduated compression healing occurred more rapidly in patients with a smaller initial ulcer area (relative risk of healing 1.92 associated with halving of ulcer area (95% confidence interval 1.58 to 2.33)), shorter duration of ulceration (relative risk 1.35 associated with halving duration (1.17 to 1.56)), younger age (relative risk 1.34 associated with 10 year decrease (1.12 to 1.59)), and no deep vein involvement (relative risk 1.8 (1.19 to 2.78)). CONCLUSION--These prognostic factors used in a simple scoring system predict time to healing.  相似文献   
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Skene  Keith R. 《Annals of botany》2000,85(6):901-908
Cluster roots, also known as proteoid roots, are one of themajor adaptations for nutrient acquisition in terrestrial vascularsporophytes, occurring in many important plant families, inkey areas of biodiversity, and in significant ecological niches.Their development and function are closely linked and presentan ideal experimental system with which to investigate the basisof pattern and its morphogenetic amplification. Both meristemfunction and root initiation are controlled within a spatialand temporal framework, resulting in predictive phenotypic expression.In this paper, these patterns of development are described withinthe context of our knowledge of lateral root initiation anddevelopment. Recent work is summarized in an attempt to highlightthe issues of most importance for future research. The caseof the genus Lupinus is taken as a means of exploring the phylogeneticrelationships of species with cluster roots. The first evidenceof cluster roots having arisen only once within the Lupinusgenus is presented. Copyright 2000 Annals of Botany Company Cluster root, development, lateral root, lupin evolution, nutrient acquisition, pattern, proteoid root  相似文献   
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Novel small molecules were synthesized and evaluated as retinoic acid receptor-related orphan receptor-gamma t (RORγt) inverse agonists for the treatment of inflammatory and autoimmune diseases. A hit compound, 1, was discovered by high-throughput screening of our compound library. The structure–activity relationship (SAR) study of compound 1 showed that the introduction of a chlorine group at the 3-position of 4-cyanophenyl moiety increased the potency and a 3-methylpentane-1,5-diamide linker is favorable for the activity. The carbazole moiety of 1 was also optimized; a quinazolinedione derivative 18i suppressed the increase of IL-17A mRNA level in the lymph node of a rat model of experimental autoimmune encephalomyelitis (EAE) upon oral administration. These results indicate that the novel quinazolinedione derivatives have great potential as orally available small-molecule RORγt inverse agonists for the treatment of Th17-driven autoimmune diseases. A U-shaped bioactive conformation of this chemotype with RORγt protein was also observed.  相似文献   
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Removal of fruit from potted cuttings of Vitis vinifera L. increased the concentration of a cytokininglucoside in leaf tissue extracts and decreased the level of extractable gibberellin-like substances. The glucoside (of zeatin riboside) is not present in xylem exudate of V. vinifera L., and appears to be synthesized in the leaves. Berry extracts contain zeatin-riboside and smaller amounts of cytokinin-glucoside. The changes in the level of these hormones are discussed in relation to previous results on abscisic acid and phaseic acid levels in grape leaves.Abbreviations ABA abscisic acid - PA phaseic acid - GA gibberellin  相似文献   
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Members of the ADP‐ribosylation factor (ARF) family of small guanosine triphosphate–binding proteins play an essential role in membrane trafficking which subserves constitutive protein transport along exocytic and endocytic pathways within eukaryotic cell bodies. In growing neurons, membrane trafficking within motile growth cones distant from the cell body underlies the rapid plasmalemmal expansion which subserves axon elongation. We report here that ARF is a constituent of axonal growth cones, and that application of brefeldin A to neurons in culture produces a rapid arrest of axon extension that can be ascribed to inhibition of ARF function in growth cones. Our findings demonstrate a role for ARF in growth cones that is coupled tightly to the rapid growth of neuronal processes characteristic of developmental and regenerative axon elongation, and indicate that ARF participates not only in constitutive membrane traffic within the cell body, but also in membrane dynamics within growing axon endings. © 1999 John Wiley & Sons, Inc. J Neurobiol 38: 105–115, 1999  相似文献   
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The phylogenetic status of arthropods, as inferred from 18S rRNA sequences   总被引:12,自引:4,他引:12  
Partial 18S rRNA sequences of five chelicerate arthropods plus a crustacean, myriapod, insect, chordate, echinoderm, annelid, and platyhelminth were compared. The sequence data were used to infer phylogeny by using a maximum-parsimony method, an evolutionary-distance method, and the evolutionary-parsimony method. The phylogenetic inferences generated by maximum-parsimony and distance methods support both monophyly of the Arthropoda and monophyly of the Chelicerata within the Arthropoda. These results are congruent with phylogenies based on rigorous cladistic analyses of morphological characters. Results support the inclusion of the Arthropoda within a spiralian or protostome coelomate clade that is the sister group of a deuterostome clade, refuting the hypothesis that the arthropods represent the "primitive" sister group of a protostome coelomate clade. Bootstrap analyses and consideration of all trees within 1% of the length of the most parsimonious tree suggest that relationships between the nonchelicerate arthropods and relationships within the chelicerate clade cannot be reliably inferred with the partial 18S rRNA sequence data. With the evolutionary-parsimony method, support for monophyly of the Arthropoda is found in the majority of the combinations analyzed if the coelomates are used as "outgroups." Monophyly of the Chelicerata is supported in most combinations assessed. Our analyses also indicate that the evolutionary-parsimony method, like distance and parsimony, may be biased by taxa with long branches. We suggest that a previous study's inference of the Arthropoda as paraphyletic may be the result of (a) having two few arthropod taxa available for analysis and (b) including long-branched taxa.   相似文献   
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