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21.
K. Blum A. H. Briggs J. E. Wallace C. W. Hall M. A. Trachtenberg 《Cellular and molecular life sciences : CMLS》1987,43(4):408-410
Summary Scrutiny of the data from these studies reveals that the C58/J alcohol-preferring mice have significantly lower baseline methionine-enkephalin levels in both the corpus striatum and hypothalamus compared to C3H/CHRGL/2 non-alcohol-preferring mice. In other brain regions in these two strains, specifically, pituitary, amygdala, midbrain, and hippocampus, analysis of methionine-enkephalin levels did not show any significant differences. This suggests that the hypothalamus may indeed be a specific locus involved in the regulation of alcohol intake, via the molecular interaction between neuroamines, opioid peptides, as they are influenced by genetics and environment. 相似文献
22.
T cells with receptors for IgD 总被引:3,自引:0,他引:3
The role of IgD in the immune response has been elusive, although its predominance on the cell surface suggests a receptor function. We have shown previously that euthymic but not athymic BALB/c mice, injected with IgD before antigen, exhibit enhanced antibody responses which can be transferred by T cells. Isotype-specific T cells have been reported to have both upward and downward immunoregulatory effects. Here we demonstrate the existence of T cells with receptors for IgD, and show that exposure to IgD in vivo or in vitro significantly increases the number of T delta cells in the spleen and lymph nodes but not in the thymus. The kinetics of T delta-cell appearance in vivo parallels that of the immunoenhancing effect which occurs after injection of IgD. These T delta cells are of the Lyt 1+2- T-cell phenotype. 相似文献
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We investigated the pathophysiology of neurofibromatosis-1 (NF1) in Drosophila melanogaster by inactivation or overexpression of the NF1 gene. NF1 gene mutants had shortened life spans and increased vulnerability to heat and oxidative stress in association with reduced mitochondrial respiration and elevated reactive oxygen species (ROS) production. Flies overexpressing NF1 had increased life spans, improved reproductive fitness, increased resistance to oxidative and heat stress in association with increased mitochondrial respiration and a 60% reduction in ROS production. These phenotypic effects proved to be modulated by the adenylyl cyclase/cyclic AMP (cAMP)/protein kinase A pathway, not the Ras/Raf pathway. Treatment of wild-type D. melanogaster with cAMP analogs increased their life span, and treatment of NF1 mutants with metalloporphyrin catalytic antioxidant compounds restored their life span. Thus, neurofibromin regulates longevity and stress resistance through cAMP regulation of mitochondrial respiration and ROS production, and NF1 may be treatable using catalytic antioxidants. 相似文献
26.
Todd JA Walker NM Cooper JD Smyth DJ Downes K Plagnol V Bailey R Nejentsev S Field SF Payne F Lowe CE Szeszko JS Hafler JP Zeitels L Yang JH Vella A Nutland S Stevens HE Schuilenburg H Coleman G Maisuria M Meadows W Smink LJ Healy B Burren OS Lam AA Ovington NR Allen J Adlem E Leung HT Wallace C Howson JM Guja C Ionescu-Tîrgovişte C;Genetics of Type Diabetes in Finland Simmonds MJ Heward JM Gough SC;Wellcome Trust Case Control Consortium Dunger DB Wicker LS Clayton DG 《Nature genetics》2007,39(7):857-864
The Wellcome Trust Case Control Consortium (WTCCC) primary genome-wide association (GWA) scan on seven diseases, including the multifactorial autoimmune disease type 1 diabetes (T1D), shows associations at P < 5 x 10(-7) between T1D and six chromosome regions: 12q24, 12q13, 16p13, 18p11, 12p13 and 4q27. Here, we attempted to validate these and six other top findings in 4,000 individuals with T1D, 5,000 controls and 2,997 family trios independent of the WTCCC study. We confirmed unequivocally the associations of 12q24, 12q13, 16p13 and 18p11 (P(follow-up) 相似文献
27.
Saether BE Lande R Engen S Weimerskirch H Lillegård M Altwegg R Becker PH Bregnballe T Brommer JE McCleery RH Merilä J Nyholm E Rendell W Robertson RR Tryjanowski P Visser ME 《Nature》2005,436(7047):99-102
Theoretical studies have shown that variation in density regulation strongly influences population dynamics, yet our understanding of factors influencing the strength of density dependence in natural populations still is limited. Consequently, few general hypotheses have been advanced to explain the large differences between species in the magnitude of population fluctuations. One reason for this is that the detection of density regulation in population time series is complicated by time lags induced by the life history of species that make it difficult to separate the relative contributions of intrinsic and extrinsic factors to the population dynamics. Here we use population time series for 23 bird species to estimate parameters of a stochastic density-dependent age-structured model. We show that both the strength of total density dependence in the life history and the magnitude of environmental stochasticity, including transient fluctuations in age structure, increase with generation time. These results indicate that the relationships between demographic and life-history traits in birds translate into distinct population dynamical patterns that are apparent only on a scale of generations. 相似文献
28.
Naloxone-induced inhibition of ethanol dependence in mice 总被引:3,自引:0,他引:3
29.
A. B. Ślebodziński A. L. C. Wallace 《Cellular and molecular life sciences : CMLS》1977,33(8):1108-1110
Summary The injection of thyrotropin releasing hormone into cattle resulted in a rapid decrease in the T4/T3 molar ratio. 2 breeds of cattle, Shorthorn and Africander Cross were studied. The decrease in the T4/T3 molar ratio was significantly greater in the Shorthorn breed. It is concluded that acute stimulation of the thyroid gland with TRH results in enhanced release of both T3 and T4 and that T3 is discharged more rapidly than T4. 相似文献
30.
The injection of thyrotropin releasing hormone into cattle resulted in a rapid decrease in the T4/T3 molar ratio. 2 breeds of cattle, Shorthorn and Africander Cross were studied. The decrease in the T4/T3 molar ratio was significantly greater in the Shorthorn breed. It is concluded that acute stimulation of the thyroid gland with TRH results in enhanced release of both T3 and T4 and that T3 is discharged more rapidly than T4. 相似文献