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961.
A White T C Fletcher 《Comparative biochemistry and physiology. A, Comparative physiology》1986,84(4):649-653
Plaice were maintained in the aquarium (11-12 degrees C) during May for 15 days without feeding. Within 48 hr, there was a decline in serum total lipids (P less than 0.001), phospholipids (P less than 0.01), triglycerides (P less than 0.001), cortisol (P less than 0.01) and glucose (P less than 0.001), but an increase in nonesterified fatty acids (NEFA; P less than 0.01). There was a significant inverse correlation between NEFA and glucose over 15 days (P less than 0.001) and between NEFA and cortisol over the first 5 days (P less than 0.01). Cortisol and glucose showed a significant correlation over 15 days (P less than 0.01). Serum cortisol and glucose were not apparently affected by starvation. Only cortisol provided a sensitive indicator of aquarium disturbance. Exposure of the fish to agitation or reduced O2 for 1 hr significantly elevated cortisol (P less than 0.001) but only the latter treatment elevated glucose (P less than 0.01); neither treatment affected the lipids. 相似文献
962.
Possible Loss of Length Conservation and Reciprocity during Recombination or Conversion in Tandem Arrays
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H. L. Fletcher 《Genetics》1994,138(2):511-518
Recombination or conversion between arrays of repeated sequences need not be conservative for length because two single strands of DNA from one chromatid may form heteroduplexes in different registers on the other participating duplex. This can cause an overall change in repeat number. Loss of length conservation is equally possible whether models of recombination initiated by single-strand transfer or double-strand break are applicable. Length changing conversion will frequently produce a characteristic insertion within a deletion, often appearing as a double deletion such as are frequently found in new variants of human minisatellite MS32. There is no apparent means of preserving parity during length-changing conversion or recombination, and if the changes are biased then the overall copy number will increase or decrease according to that bias. The observation that arrays persist suggests that any bias in these arrays will be toward gains. An equilibrium may be reached where gains, which may be largely independent of array length, equal losses from the array-length-dependent processes of intrachromatid recombination and repeated unequal sister chromatid exchanges. 相似文献
963.
A J Ashraf G M Smith T C Fletcher 《Comp. Biochem. Physiol. C, Comp. Pharmacol. Toxicol.》1985,81(1):53-56
A methanolic extract of plaice skin, from which lipids had been removed, was chromatographed on alumina, eluted with decreasing concentrations of ethanol. Only the 60% ethanol fraction exhibited smooth muscle activity, with bradykinin-like properties. The 20% ethanol fraction increased vascular permeability in rat skin, as measured by dye-leakage. This was not due to the degranulation of mast cells. Intradermal injection of either fraction into the plaice caused localized erythema. 相似文献
964.
The expression of alpha(1)-acid glycoprotein mRNA during rat development. High levels of expression in the decidua 总被引:1,自引:0,他引:1
T Thomas S Fletcher G C Yeoh G Schreiber 《The Journal of biological chemistry》1989,264(10):5784-5790
During the acute phase response to inflammation the plasma concentration of some proteins, such as alpha(1-acid glycoprotein (AGP), increases dramatically. Since breakdown and remodeling of tissue is common to both nidation and inflammation we studied the tissue distribution and regulation of AGP mRNA levels during the embryonic development of the rat. High levels of mRNA coding for AGP were detected in the placenta during early fetal development. Expression of this mRNA was confined to the decidua and was first observed approximately 1 day after implantation when proliferation of the decidua is already well advanced. Maximum levels were attained about 5 days after implantation, after which the levels decreased rapidly. In contrast to the high levels of AGP mRNA in the decidua only very low levels were detected in fetal liver and visceral yolk sac, and there was only a small increase in the levels in maternal liver. Corticosteroid hormone responsiveness of AGP mRNA synthesis by hepatocytes appeared 3 days before birth. It is likely that the synthesis of AGP by the cells of the decidua is important in establishing the precisely controlled interaction between mother and embryo during nidation. 相似文献
965.
966.
967.
Mechanical cues influence a wide range of cellular behaviors including motility, differentiation, and tumorigenesis. Although previous studies elucidated the role of specific players such as ion channels and focal adhesions as local mechanosensors, the investigation of how mechanical perturbations propagate across the cell is necessary to understand the spatial coordination of cellular processes. Here we quantify the magnitude and timing of intracellular stress propagation, using atomic force microscopy and particle tracking by defocused fluorescence microscopy. The apical cell surface is locally perturbed by atomic force microscopy cantilever indentation, and distal displacements are measured in three dimensions by tracking integrin-bound fluorescent particles. We observe an immediate response and slower equilibration, occurring over times that increase with distance from perturbation. This distance-dependent equilibration occurs over several seconds and can be eliminated by disruption of the actin cytoskeleton. Our experimental results are not explained by traditional viscoelastic models of cell mechanics, but they are consistent with predictions from poroelastic models that include both cytoskeletal deformation and flow of the cytoplasm. Our combined atomic force microscopy-particle tracking measurements provide direct evidence of slow, distance-dependent dissipative stress propagation in response to external mechanical cues and offer new insights into mechanical models and physiological behaviors of adherent cells. 相似文献
968.
Abstract A review of the Aphrophoridae (Hemiptera: Auchenorrhyncha: Cercopoidea) occurring in Australia has revealed closer links between the Australian fauna and those of the Pacific region than were previously acknowledged. A key to the Australian genera is provided along with a diagnosis for each genus and a list of described Australian species with notes on each. Taxonomic changes proposed are: Neoaphrophora China synonymised with Anyllis Kirkaldy; Eurycercopis Kirkaldy synonymised with Interocrea Walker; Aphrophora rufiventris Walker and Philagra vittata Metcalf and Horton synonymised with Philagra parva (Donovan). New combinations proposed are: Amarusa australis (Jacobi) (from Eoptyelus ); Anyllis tiegsi (China) (from Neoaphrophora ); Interocrea nigrofasciata (Kirkaldy) (from Eurycercopis ); Interocrea regalis (Lallemand) (from Clovia ); Liorhina loxosema (Hacker) (from Clovia ). To provide a single reference point for the species and, for species described by Hacker (1926) and Jacobi (1928) , to validate apparent holotype intentions by those authors, lectotypes are designated for: Ptyelus homochrous Hacker; Eurycercopis nigrofasciata Kirkaldy; Clovia regalis Lallemand; Clovia loxosema Hacker; Philagra concolor Hacker; Philagra fulvida Hacker; Philagra recurva Jacobi. The probable whereabouts of the type specimen of Philagra parva (Donovan) are discussed. The origin of the holotype of Novaphrophara tasmaniae Lallemand is discussed; the Australian record is almost certainly incorrect. 相似文献
969.
Ronald Palin John K. Clark Louise Evans Helen Feilden Dan Fletcher Niall M. Hamilton Andrea K. Houghton Philip S. Jones Duncan McArthur Brian Montgomery Paul D. Ratcliffe Alasdair R.C. Smith Aaron Sutherland Mark A. Weston Grant Wishart 《Bioorganic & medicinal chemistry letters》2009,19(22):2482-6446
A knowledge based approach has been adopted to identify novel NOP receptor agonists with simplified hydrophobes. Substitution of the benzimidazol-2-one piperidine motif with a range of hydrophobic groups and pharmacophore guided bio-isosteric replacement of the benzimidazol-2-one moiety was explored. Compound 51 was found to be a high affinity, potent NOP receptor agonist with reduced affinity for the hERG channel. 相似文献
970.
Lloyd G. Czaplewski Ian Collins E. Andrew Boyd David Brown Stephen P. East Mihaly Gardiner Rowena Fletcher David J. Haydon Vincent Henstock Peter Ingram Clare Jones Caterina Noula Leanne Kennison Chris Rockley Valerie Rose Helena B. Thomaides-Brears Rebecca Ure Mark Whittaker Neil R. Stokes 《Bioorganic & medicinal chemistry letters》2009,19(2):524-527
3-Methoxybenzamide is a weak inhibitor of the essential bacterial cell division protein FtsZ. Exploration of the structure–activity relationships of 3-methoxybenzamide analogues led to the identification of potent anti-staphylococcal compounds. 相似文献