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21.
J. C. Cole G. J. Burroughs C. R. Laverty N. C. Sheriff E. A. Sparham R. J. Rodgers 《Psychopharmacology》1995,118(4):425-436
The influence of 2-adrenoceptor antagonists in animal models of anxiety is quite inconsistent, with results spanning the full range of effect from anxiogenesis to anxiolysis. In the present study, an ethological technique was used to examine the effects of yohimbine (0.5–4.0 mg/kg) on plus-maze behaviour in DBA/2 mice. Results indicated significantanxiolytic-like effects on standard spatiotemporal measures at 2.0–4.0 mg/kg, and on risk assessment measures across the entire dose range. Full-scale follow-up studies with T1 and BALB/c strains confirmed that this action of yohimbine in the murine plus-maze is not peculiar to DBA/2 mice. The more selective 2-adrenoceptor antagonist, idazoxan (0.63–5.0 mg/kg), exerted much weaker behavioural effects in the maze while the 2-adrenoceptor agonist, clonidine (0.01–0.1 mg/kg), produced a profile consistent with non-specific behavioural disruption. Data are discussed in relation to the possible involvement of 5-HT1A receptor mechanisms in the observed anxiolytic-like effects of yohimbine in the murine plus-maze. 相似文献
22.
Liver disease in Europe 总被引:1,自引:0,他引:1
23.
Ramona Prillhofer Gunther Rank Josef Berneder Helmut Antrekowitsch Peter J. Uggowitzer Stefan Pogatscher 《Materials》2014,7(7):5047-5068
In this study, property criteria for automotive Al-Mg-Si sheet alloys are outlined and investigated in the context of commercial alloys AA6016, AA6005A, AA6063 and AA6013. The parameters crucial to predicting forming behavior were determined by tensile tests, bending tests, cross-die tests, hole-expansion tests and forming limit curve analysis in the pre-aged temper after various storage periods following sheet production. Roping tests were performed to evaluate surface quality, for the deployment of these alloys as an outer panel material. Strength in service was also tested after a simulated paint bake cycle of 20 min at 185 °C, and the corrosion behavior was analyzed. The study showed that forming behavior is strongly dependent on the type of alloy and that it is influenced by the storage period after sheet production. Alloy AA6016 achieves the highest surface quality, and pre-ageing of alloy AA6013 facilitates superior strength in service. Corrosion behavior is good in AA6005A, AA6063 and AA6016, and only AA6013 shows a strong susceptibility to intergranular corrosion. The results are discussed below with respect to the chemical composition, microstructure and texture of the Al-Mg-Si alloys studied, and decision-making criteria for appropriate automotive sheet alloys for specific applications are presented. 相似文献
24.
25.
The design of a novel band-pass filter with narrow-band features based on an electromagnetic resonator at 6.4 GHz is presented. A prototype is manufactured and characterized in terms of transmission and reflection coefficient. The selective passband and suppression of the second harmonic make the filter suitable to be used in a C band frequency range for radar systems and satellite/terrestrial applications. To avoid substantial interference for this kind of applications, passive components with narrow band features and small dimensions are required. Between 3.6 GHz and 4.2 GHz the band-pass filter with harmonic suppression should have an attenuation of at least 35 dB, whereas for a passband, less than 10% is sufficient. 相似文献
26.
Carolin Lübker Stefan Dove Wei-Jen Tang Ramona J. Bieber Urbauer Jackob Moskovitz Jeffrey L. Urbauer Roland Seifert 《Toxins》2015,7(7):2598-2614
Bacillus anthracis adenylyl cyclase toxin edema factor (EF) is one component of the anthrax toxin and is essential for establishing anthrax disease. EF activation by the eukaryotic Ca2+-sensor calmodulin (CaM) leads to massive cAMP production resulting in edema. cAMP also inhibits the nicotinamide adenine dinucleotide phosphate (NADPH)-oxidase, thus reducing production of reactive oxygen species (ROS) used for host defense in activated neutrophils and thereby facilitating bacterial growth. Methionine (Met) residues in CaM, important for interactions between CaM and its binding partners, can be oxidized by ROS. We investigated the impact of site-specific oxidation of Met in CaM on EF activation using thirteen CaM-mutants (CaM-mut) with Met to leucine (Leu) substitutions. EF activation shows high resistance to oxidative modifications in CaM. An intact structure in the C-terminal region of oxidized CaM is sufficient for major EF activation despite altered secondary structure in the N-terminal region associated with Met oxidation. The secondary structures of CaM-mut were determined and described in previous studies from our group. Thus, excess cAMP production and the associated impairment of host defence may be afforded even under oxidative conditions in activated neutrophils. 相似文献
27.
Circulating tumor cells (CTCs) are isolated tumor cells disseminated from the site of disease in metastatic and/or primary
cancers, including breast cancer, that can be identified and measured in the peripheral blood of patients. As recent technical
advances have rendered it easier to reproducibly and repeatedly sample this population of cells with a high degree of accuracy,
these cells represent an attractive surrogate marker of the site of disease. 相似文献
28.
Ulrike Weber-Stadlbauer Juliet Richetto Ramona A. J. Zwamborn Roderick C. Slieker Urs Meyer 《Neuropsychopharmacology》2021,46(2):404
Prenatal exposure to infectious and/or inflammatory insults is increasingly recognized to contribute to the etiology of psychiatric disorders with neurodevelopmental components. Recent research using animal models suggests that maternal immune activation (MIA) can induce transgenerational effects on brain and behavior, possibly through epigenetic mechanisms. Using a mouse model of MIA that is based on gestational treatment with the viral mimeticpoly(I:C) (= polyriboinosinic-polyribocytidilic acid), the present study explored whether the transgenerational effects of MIA are extendable to dopaminergic dysfunctions. We show that the direct descendants born to poly(I:C)-treated mothers display signs of hyperdopaminergia, as manifested by a potentiated sensitivity to the locomotor-stimulating effects of amphetamine (Amph) and increased expression of tyrosine hydroxylase (Th) in the adult ventral midbrain. In stark contrast, second- and third-generation offspring of MIA-exposed ancestors displayed blunted locomotor responses to Amph and reduced expression of Th. Furthermore, we found increased DNA methylation at the promoter region of the dopamine-specifying factor, nuclear receptor-related 1 protein (Nurr1), in the sperm of first-generation MIA offspring and in the ventral midbrain of second-generation offspring of MIA-exposed ancestors. The latter effect was further accompanied by reduced mRNA levels of Nurr1 in this brain region. Together, our results suggest that MIA has the potential to modify dopaminergic functions across multiple generations with opposite effects in the direct descendants and their progeny. The presence of altered DNA methylation in the sperm of MIA-exposed offspring highlights the possibility that epigenetic processes in the male germline play a role in the transgenerational effects of MIA.Subject terms: Neuroimmunology, Developmental disorders 相似文献
29.
Margaret S. Herridge Marc Moss Catherine L. Hough Ramona O. Hopkins O. Joseph Bienvenu Elie Azoulay 《Intensive care medicine》2016,42(5):725-738
Outcomes after acute respiratory distress syndrome (ARDS) are similar to those of other survivors of critical illness and largely affect the nerve, muscle, and central nervous system but also include a constellation of varied physical devastations ranging from contractures and frozen joints to tooth loss and cosmesis. Compromised quality of life is related to a spectrum of impairment of physical, social, emotional, and neurocognitive function and to a much lesser extent discrete pulmonary disability. Intensive care unit-acquired weakness (ICUAW) is ubiquitous and includes contributions from both critical illness polyneuropathy and myopathy, and recovery from these lesions may be incomplete at 5 years after ICU discharge. Cognitive impairment in ARDS survivors ranges from 70 to 100 % at hospital discharge, 46 to 80 % at 1 year, and 20 % at 5 years, and mood disorders including depression and post-traumatic stress disorder (PTSD) are also sustained and prevalent. Robust multidisciplinary and longitudinal interventions that improve these outcomes are still uncertain and data in our literature are conflicting. Studies are needed in family members of ARDS survivors to better understand long-term outcomes of the post-ICU family syndrome and to evaluate how it affects patient recovery. 相似文献
30.
Ramona Robinson-O'Brien Bonnie L. Gerald 《Journal of the Academy of Nutrition and Dietetics》2013,113(3):464
Registered dietitians (RDs) and dietetic technicians, registered (DTRs) can implement environmentally responsible practices in their workplace and personal lives. RDs and DTRs who conserve natural resources while minimizing environmental degradation will help maintain sustainability of the food system, which requires knowledge of the external costs of operational and personal decisions. These external costs include energy to produce, transport, and process food; water for food production, preparation, and sanitation; removal of air pollutants; and waste management. As client and public educators, RDs and DTRs are uniquely positioned to meet the growing needs of those seeking guidance on food choices as they relate to ecological sustainability. In an effort to promote ecologically sustainable diets, it is important to consider natural resources as they relate to food production, transformation, distribution, access, and consumption. It is essential that the dietetics community takes a more active leadership role in support of ecological sustainability and social responsibility. RDs and DTRs can influence policy at the institutional, community, local, state, and national levels by presenting results of operational practices and science-based natural resource information. RDs and DTRs are encouraged to become educated and active in implementing sustainable practices and shaping policy in an effort to promote healthier individuals, communities, and the nation as a whole. 相似文献