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991.
G A Strobel E Ford J Y Li J Sears R S Sidhu W M Hess 《Systematic and applied microbiology》1999,22(3):426-433
Seimatoantlerium gen. nov., type species, S. tepuiense sp. nov. is proposed for an acervular fungus producing 4-septate, holoblastic conidia with 6-8 unbranched, apical appendages that dehisce as an appendage apparatus and also commonly possessing one or two exogenous basal appendages as well as a pedicel. It is compared with Seimatosporium, Seimatosporiopsis, and other genera. It is epiphytic on Maguireothamnus speciosus, a rubiaceous plant endemic to the tepuis of southeastern Venezuela. It produces the anti-oomycetous anticancer compound, taxol, as shown by immunological and spectroscopic methods. Taxol production is discussed relative to the ability of this fungus to exist in an extremely moist ecosystem, as well as to its relationship to other plant associated fungi. 相似文献
992.
Johnson PD Aristoff PA Zurenko GE Schaadt RD Yagi BH Ford CW Hamel JC Stapert D Moerman JK 《Bioorganic & medicinal chemistry letters》2003,13(23):4197-4200
Novel benzazepine oxazolidinone antibacterials were synthesized and evaluated against clinically relevant susceptible and resistant organisms. The effect of ring nitrogen position and N-substitution on antibacterial activity is examined. 相似文献
993.
Ciske FL Barbachyn MR Genin MJ Grega KC Lee CS Dolak LA Seest EP Watt W Adams WJ Friis JM Ford CW Zurenko GE 《Bioorganic & medicinal chemistry letters》2003,13(23):4235-4239
The oxazolidinones are promising agents for the treatment of infections caused by gram-positive bacteria, including multidrug-resistant strains. In ongoing studies we have discovered that a strategically placed chiral center of appropriate absolute configuration improves the antibacterial activity of indolinyl oxazolidinone analogues (gram-positive MIC's<0.5 microg/mL for the most potent congeners). The design, synthesis, antibacterial activity and pharmacokinetic profile of a selected series of alpha-methylated indoline derivatives and a related set of tetrahydroquinolyl and dihydrobenzoxazinyl analogues are discussed. 相似文献
994.
doi: 10.1111/j.1741‐2358.2010.00438.x Evaluation of experimental cleanser solution of Ricinus communis: effect on soft denture liner properties Objective: This study evaluated colour stability, hardness and roughness of soft denture liners after immersion in various cleansers. Materials and methods: Thirty specimens (14 mm × 4 mm) of Elite Soft Relining (ES) and Mucopren Soft (MS) were randomly immersed in distilled water at 37°C, sodium hypochlorite 1%, and an experimental Ricinus communis solution (RC) for 7, 15 and 183 continuous days. Results: anova (p < 0.05) and Tukey’s test indicated that after T7 (μ =8.79 ± 7.36); T15 (μ = 4.23 ± 2.62) and T183 (μ = 8.78 ± 3.16), MS presented a higher increase in hardness than ES. After T7, MS underwent an increase in roughness (μ = 0.09 ± 0.80); ES underwent a decrease (μ = ?0.08 ± 0.16). RC caused the smallest variation in roughness. After T15, both materials presented an increase in roughness. After T183, ES (μ = ?0.30 ± 0.48) presented a higher roughness variation than MS (μ = ?0.07 ± 0.32). Hypochlorite caused an increase in roughness (μ = 0.02 ± 0.19). Conclusion: After all periods ES presented higher colour alteration than MS; highest colour alteration was caused by hypochlorite. Both materials were more stable after immersion in RC. 相似文献
995.
996.
Abreu AP Noel SD Xu S Carroll RS Latronico AC Kaiser UB 《Molecular endocrinology (Baltimore, Md.)》2012,26(8):1417-1427
Prokineticin receptors (PROKR) are G protein-coupled receptors (GPCR) that regulate diverse biological processes, including olfactory bulb neurogenesis and GnRH neuronal migration. Mutations in PROKR2 have been described in patients with varying degrees of GnRH deficiency and are located in diverse functional domains of the receptor. Our goal was to determine whether variants in the first intracellular loop (ICL1) of PROKR2 (R80C, R85C, and R85H) identified in patients with hypogonadotropic hypogonadism interfere with receptor function and to elucidate the mechanisms of these effects. Because of structural homology among GPCR, clarification of the role of ICL1 in PROKR2 activity may contribute to a better understanding of this domain across other GPCR. The effects of the ICL1 PROKR2 mutations on activation of signal transduction pathways, ligand binding, and receptor expression were evaluated. Our results indicated that the R85C and R85H PROKR2 mutations interfere only modestly with receptor function, whereas the R80C PROKR2 mutation leads to a marked reduction in receptor activity. Cotransfection of wild-type (WT) and R80C PROKR2 showed that the R80C mutant could exert a dominant negative effect on WT PROKR2 in vitro by interfering with WT receptor expression. In summary, we have shown the importance of Arg80 in ICL1 for PROKR2 expression and demonstrate that R80C PROKR2 exerts a dominant negative effect on WT PROKR2. 相似文献
997.
Schmidt-Bleek K Schell H Schulz N Hoff P Perka C Buttgereit F Volk HD Lienau J Duda GN 《Cell and tissue research》2012,347(3):567-573
Bone healing commences with an inflammatory reaction which initiates the regenerative healing process leading in the end to
reconstitution of bone. An unbalanced immune reaction during this early bone healing phase is hypothesized to disturb the
healing cascade in a way that delays bone healing and jeopardizes the successful healing outcome. The immune cell composition
and expression pattern of angiogenic factors were investigated in a sheep bone osteotomy model and compared to a mechanically-induced
impaired/delayed bone healing group. In the impaired/delayed healing group, significantly higher T cell percentages were present
in the bone hematoma and the bone marrow adjacent to the osteotomy gap when compared to the normal healing group. This was
mirrored in the higher cytotoxic T cell percentage detected under delayed bone healing conditions indicating longer pro-inflammatory
processes. The highly activated periosteum adjourning the osteotomy gap showed lower expression of hematopoietic stem cell
markers and angiogenic factors such as heme oxygenase and vascular endothelial growth factor. This indicates a deferred revascularization
of the injured area due to ongoing pro-inflammatory processes in the delayed healing group. Results from this study suggest
that there are unfavorable immune cells and factors participating in the initial healing phase. In conclusion, identifying
beneficial aspects may lead to promising therapeutical approaches that might benefit further by eliminating the unfavorable
factors. 相似文献
998.
999.
Edwin W. Taylor Nini Skovgaard Cleo A.C. Leite Marina Sartori Gabrielle S. de Paula Augusto S. Abe 《Journal of thermal biology》2012
Bullfrogs, Lithobathes catesbeianus, bearing a femoral artery cannula were held at 3 temperatures (10, 20 and 30 °C) for 24 h. Changes in heart rate were recorded before and after injection of cholinergic and adrenergic antagonists. Normal heart rate doubled for each temperature increment. Adrenergic tone on the heart varied around 20% at all 3 temperatures but cholinergic tone increased from −5% to 10% between 10 and 30 °C. In contrast, cholinergic tone increased from 75% at 5 °C to 329% at 25 °C in Xenopus laevis. Injection of the neural tracer True Blue into the cervical vagus of the bullfrog revealed a single location for vagal preganglionic neurons (VPN) in the dorsal vagal motor nucleus (DVN), while Xenopus had 30% of its VPN in a ventro-lateral group outside the DVN. Broader comparative studies have suggested that differences in the extent of vagal tone may relate to the location of VPN in the brainstem and this may be the case in these amphibians. 相似文献
1000.
Varela-Silva MI Dickinson F Wilson H Azcorra H Griffiths PL Bogin B 《Collegium antropologicum》2012,36(1):39-45
This paper focuses on the phenomenon of the nutritional dual-burden in the developing world. Nutritional dual-burden is defined as the coexistence of under-and-over nutrition in the same population/group, the same household/family, or the same person. In this paper we aim: a) to describe the different types of nutritional dual-burden, b) to identify the anthropometric indicators generally used to classify the nutritional dual-burden, c) to focus our attention on a dual-burden group (the Maya from Merida, Yucatan, Mexico), d) to illustrate problems in the categorization of the dual-burden, and e) to suggest possible health implications. Our results show that, for our sample, the prevalence of individual dual-burden among children is very low, but is very high among the mothers and for mother-child pairs (household dual-burden). Most importantly, the criteria used to assess the nutritional status of the individuals and of the families will play an important role in the estimated prevalence of nutritional dual-burden, and this will have practical impacts for health intervention programs. 相似文献