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31.
Novel hydroxy-cis-enynoic acids have been prepared. Those of type
C(CH2)6CO2H have been found to cyclise to furanoid acids on treatment with alkali, or on chromatography on argentous silica gel. The hydroxy-cis-enynoic acids stimulate smooth muscle, the furanoid acids are not similarly active.  相似文献   
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We describe polymorphism in aDrosophila indirect flight muscle-specific tropomyosin isozyme, named TnH-34. Three variants of this protein differ in their mobilities as determined by 1-D and 2-D SDS-PAGE. Meiotic mapping places the polymorphism close to, if not within, the structural gene encoding this tropomyosin isozyme. The most likely site of the mutations is within a single C-terminal exon. Flight-testing of different genotypes reveals that this variation in TnH-34 does not affect flight ability. These results suggest that some sequence variation may be tolerated in this section of the protein and correlate with the variability of this protein in different insect species. This work was supported by an SERC studentship to R.M.C. and SERC Research Grant GR/F17827 awarded to J.C.S. and Dr. David White.  相似文献   
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OBJECTIVE--To determine the potential number of cadaver kidney donors by applying defined donor criteria to people dying in hospital. DESIGN--Prospective study of all deaths occurring in 21 hospitals from 1 September 1988 to 31 August 1989. Questionnaires were administered to medical and nursing staff and families of potential donors aged 1-69. SETTING--Acute care hospitals in Gwent, South Glamorgan, Mid Glamorgan, West Glamorgan, Pembrokeshire, and East Dyfed health authorities, serving a population of 2.2 million. MAIN OUTCOME MEASURES--Cause of death, age, ventilation at time of death, diagnosis of brain death, and consideration of consent. RESULTS--Adequate data were available for 9840 of 10,095 hospital deaths (97.5% coverage). 188 patients aged 0-69 were identified as potential organ donors (widest definition), and of these 108 died without being ventilated at the time of death. Tests of brain stem death were formally completed in 57 cases, and organ donation was considered by the families of 47 of these potential donors. 26 patients became organ donors. Patients aged 50-69 with stroke were less likely to be ventilated than those aged less than or equal to 49 (21/96 v 24/34). Families of potential donors aged 20-39 were least likely to give permission. CONCLUSIONS--The supply of donor organs (specifically kidneys) could be increased by altering the management of patients aged 50-69 dying of severe cerebrovascular disease in general medical wards, in particular by increasing the proportion ventilated. The ethics of elective ventilation for the purposes of organ donation require discussion.  相似文献   
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Ectomycorrhizae formed in synthesis tubes by aspen (Populus tremuloides) seedlings and each of seven fungal isolates are described. Isolates of Amanita muscaria v. formosa, A. pantherina, Inocybe lacera, and Paxillus vernalis, from sporocarps collected in aspen stands in southwestern Montana, developed mantles and Hartig nets on aspen roots, as did the broad-hostrange fungi Cenococcum geophilum and Pisolithus tinctorius from the VPI culture collection. Chalciporus piperatus failed to form mycorrhizae, and Piloderma croceum formed a mantle, but no Hartig net. The first syntheses of I. lacera and A. pantherina with aspen are reported.  相似文献   
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In this study, temporal and spatial distribution of three TGF‐β isoforms and their downstream signaling pathways including pSmad2 and p38MAPK were examined during fibrotic wound repair. In normal chick corneas, TGF‐β1, ‐2, and ‐3 were weakly detected in Bowman's layer (BL). In healing corneas, TGF‐β1 was primarily deposited in the fibrin clot and the unwounded BL. TGF‐β2 was highly expressed in healing epithelial and endothelial cells, and numerous active fibroblasts/myofibroblasts. TGF‐β3 was mainly detected in the unwound region of basal epithelial cells. α‐Smooth muscle actin (α‐SMA) was initially appeared in the posterior region of repairing stroma at day 3, and was detected in the entire healing stroma by day 7. Notably, α‐SMA was absent in the central region of healing stroma by day 14, and its staining pattern was similar to those of TGF‐β2 and p38MAPK. By contrast, pSmad2 was mainly detected in the fibroblasts. In normal cornea, laminin was mainly detected in both epithelial basement membrane (BM) and Descemet's membrane (DM). By contrast to reconstitution of the BM in the wound region, the DM was not repaired although endothelial layer was regenerated, indicating that high levels of TGF‐β2 were released into the posterior region of healing stroma on day 14. High levels of α‐SMA staining, shown in cultured repair stromal cells from healing corneas on day 14 and in TGF‐β2 treated normal stromal cells, were significantly reduced by p38MAPK inhibition. Collectively, this study suggests that TGF‐β2‐mediated myofibroblast transformation is mediated, at least partly, by the p38MAPK pathway in vivo. J. Cell. Biochem. 108: 476–488, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
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N-(Pyridin-2-yl) arylsulfonamides are identified as inhibitors of 11β-hydroxysteroid dehydrogenase type 1 (11βHSD1), an enzyme that catalyzes the reduction of the glucocorticoid cortisone to cortisol. Dysregulation of glucocorticoids has been implicated in the pathogenesis of diabetes and the metabolic syndrome. In this Letter, we present the development of an initial lead to an efficient ligand with improved physiochemical properties using a deletion strategy. This strategy allowed for further optimization of potency leading to the discovery of the clinical candidate PF-915275.  相似文献   
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