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231.
Vertical polyacrylamide gel electrophoresis was used to resolve enzymes at 50 putative loci in Iowa face flies, a recently arrived, colonizing, Palearctic species. Sixty-two percent of the 50 loci were polymorphic. The mean number of alleles per polymorphic locus was 3.2 +/- 1.38; the mean among all loci was 2.38 +/- 1.62 alleles. The effective number of alleles among 50 loci was 1.4 +/- 0.62. Mean observed and expected heterozygosities for the 50 face fly loci were 0.167 +/- 0.037 and 0.186 +/- 0.031, respectively. Comparison of the electrophoretic data for Musca autumnalis and for M. domestica L. showed similar high levels of gene diversity. A survey of gene diversity at 12 loci among six geographically independent laboratory colonies demonstrated statistically significant genetic differentiation that was probably due to drift after colonization.  相似文献   
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Summary The striatum receives the majority of excitatory amino acidergic input to the basal ganglia from neocortical and allocortical sources. The subthalamic nucleus and the substantia nigra also receive excitatory amino acidergic inputs from neocortex. The subthalamic nucleus, which has prominent projections to the pallidum and nigra, is the only known intrinsic excitatory amino acidergic component of the basal ganglia. Possible excitatory amino acidergic inputs reach the basal ganglia from the intralaminar thalamic nuclei and the pedunculo-pontine nucleus. The striatum is richly endowed with all subtypes of excitatory amino acid receptors and these appear to be inhomogeneously distributed within the striatal complex. The non-striatal nuclei contain lesser levels of excitatory amino acid receptors and the relative proportion of these receptors varies between nuclei. The presence of high densities of excitatory amino acid receptors is a phylogenetically conserved feature of the striatum and its non-mammalian homologues. In Huntington's disease, there is substantial depletion of-amino-3-hydroxy-5-methylisoxazole-4-propionic acid, N-methyl-D-aspartate, and kainate receptors within the striatum. In Parkinson's disease substantia nigra, there is significant loss of N-methyl-D-aspartate and-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptors.  相似文献   
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The effect of three pleasant fine women's fragrances on the mood of women was assessed. The three fragrances had similar hedonic values but different sensory characteristics. The fragrances elicited nonspecific effects on mood. All three fragrances’ impact on mood was influenced by initial mood and lasted up to three hours, i.e., as long as the scent was still noticeable. Trends revealed that all three fragrances decreased negative affect and increased vigor. Also, independent of their hedonic value, the three fragrances elicited specific mood patterns. With the “woody citrus coniferous” scent, respondents experienced higher hostility and tension. The “floral chypre citrus” fragrance decreased anger and confusion. The “floral woody” scent had the lowest Total Mood Disturbance score and lowered depression, tension and confusion.  相似文献   
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Homeostasis is essential for cell survival. However, homeostatic regulation of surface epithelia is poorly understood. The eye surface, lacking the cornified barrier of skin, provides an excellent model. Tears cover the surface of the eye and are deficient in dry eye, the most common eye disease affecting at least 5% of the world''s population. Only a tiny fraction of the tear proteome appears to be affected, including lacritin, an epithelium-selective mitogen that promotes basal tearing when topically applied to rabbit eyes. Here we show that homeostasis of cultured corneal epithelia is entirely lacritin-dependent and elucidate the mechanism as a rapid autophagic flux to promptly restore cellular metabolism and mitochondrial fusion in keeping with the short residence time of lacritin on the eye. Accelerated flux appears to be derived from lacritin-stimulated acetylation of FOXO3 as a novel ligand for ATG101 and coupling of stress-acetylated FOXO1 with ATG7 (which remains uncoupled without lacritin) and be sufficient to selectively divert huntingtin mutant Htt103Q aggregates largely without affecting non-aggregated Htt25Q. This is in keeping with stress as a prerequisite for lacritin-stimulated autophagy. Lacritin targets the cell surface proteoglycan syndecan-1 via its C-terminal amino acids Leu108-Leu109-Phe112 and is also available in saliva, plasma, and lung lavage. Thus, lacritin may promote epithelial homeostasis widely.  相似文献   
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Studies in humans and animal models indicate that profound immunosuppression is one of the chronic consequences of severe sepsis. This immune dysfunction encompasses deficiencies in activation of cells in both the myeloid and lymphoid cell lineages. As a result, survivors of severe sepsis are at risk of succumbing to infections perpetrated by opportunistic pathogens that are normally controlled by a fully functioning immune system. Recent studies have indicated that epigenetic mechanisms may be one driving force behind this immunosuppression, through suppression of proinflammatory gene production and subsequent immune cell activation, proliferation and effector function. A better understanding of epigenetics and post-septic immunosuppression can improve our diagnostic tools and may be an important potential source of novel molecular targets for new therapies. This review will discuss important pathways of immune cell activation affected by severe sepsis, and highlight pathways of epigenetic regulation that may be involved in post-septic immunosuppression.Key words: sepsis, immunosuppression, histone modification, gene regulation, inflammation, macrophages, dendritic cells, T lymphocytes  相似文献   
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