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991.
Avalanche cascades of magnetic flux have been detected at thermomagnetic instability of the critical state in the plates of Nb-Ti alloy. It was found that, the magnetic flux Φ enters conventional superconductor in screening regime and leaves in trapping regime in the form of a multistage “stairways”, with the structure dependent on the magnetic field strength and magnetic history, with approximately equal successive portions ΔΦ in temporal Φ(t) dependence, and with the width depending almost linearly on the plate thickness. The steady generation of cascades was observed for the full remagnetization cycle in the field of 2–4 T. The structure of inductive signal becomes complex already in the field of 0–2 T and it was shown, on the base of Fourier analysis, that, the avalanche flux dynamic produces, in this field range, multiple harmonics of the electric field. The physical reason of complex spectrum of the low-field avalanche dynamics can be associated with rough structure of moving flux front and with inhomogeneous relief of induction. It was established that the initiation of cascades occurs mainly in the central part of the lateral surface. The mechanism of cascades generation seems to be connected to the “resonator’s properties” of the plates. 相似文献
992.
Adam Young Dolores Jaraquemada Juliette Awad Hilliard Festenstein Mary Corbett Frank C. Hay Ivan M. Roitt 《Arthritis \u0026amp; Rheumatology》1984,27(1):20-25
Patients admitted to a prospective study within a year of onset of suspected rheumatoid arthritis showed a positive correlation between HLA-Dw4 and the eventual severity of peripheral radiologic changes. Dw4 and DR4 were strongly associated with severity of erosions when analysis was restricted to each of the following: patients with erosions, those under 50 at onset, and all females. Relationships were consistently stronger with Dw4 than with DR4. Another D-related specificity, MT3, was positively correlated and Dw2/DR2 negatively correlated with erosions. 相似文献
993.
Alex Buga Gary L. Welton Katie E. Scott Adam D. Atwell Sarah J. Haley Noah J. Esbenshade Jacqueline Abraham Jeffrey D. Buxton Dana L. Ault Amy S. Raabe Timothy D. Noakes Parker N. Hyde Jeff S. Volek Philip J. Prins 《Nutrients》2022,14(6)
A growing number of endurance athletes have considered switching from a traditional high-carbohydrate/low-fat (HCLF) to a low-carbohydrate/high-fat (LCHF) eating pattern for health and performance reasons. However, few studies have examined how LCHF diets affect blood lipid profiles in highly-trained runners. In a randomized and counterbalanced, cross-over design, athletes (n = 7 men; VO2max: 61.9 ± 6.1 mL/kg/min) completed six weeks of two, ad libitum, LCHF (6/69/25% en carbohydrate/fat/protein) and HCLF (57/28/15% en carbohydrate/fat/protein) diets, separated by a two-week washout. Plasma was collected on days 4, 14, 28, and 42 during each condition and analyzed for: triglycerides (TG), LDL-C, HDL-C, total cholesterol (TC), VLDL, fasting glucose, and glycated hemoglobin (HbA1c). Capillary blood beta-hydroxybutyrate (BHB) was monitored during LCHF as a measure of ketosis. LCHF lowered plasma TG, VLDL, and TG/HDL-C (all p < 0.01). LCHF increased plasma TC, LDL-C, HDL-C, and TC/HDL-C (all p < 0.05). Plasma glucose and HbA1c were unaffected. Capillary BHB was modestly elevated throughout the LCHF condition (0.5 ± 0.05 mmol/L). Healthy, well-trained, normocholesterolemic runners consuming a LCHF diet demonstrated elevated circulating LDL-C and HDL-C concentrations, while concomitantly decreasing TG, VLDL, and TG/HDL-C ratio. The underlying mechanisms and implications of these adaptive responses in cholesterol should be explored. 相似文献
994.
Kevin B. Laupland Adam G. Stewart Felicity Edwards David L. Paterson Sonali Coulter Claire Heney Narelle George Patrick Harris 《Emerging infectious diseases》2022,28(4):701
The epidemiology of bloodstream infections caused by Shewanella spp. is not well defined. Our objective was to define the incidence and determinants of Shewanella spp. bloodstream infections by using population-based surveillance in Queensland, Australia during 2000‒2019. The incidence was 1.0 cases/1 million persons annually and was highest during summer and in the tropical Torres and Cape region. Older persons and male patients were at highest risk. At least 1 concurrent condition was documented in 75% of case-patients, and 30-day all cause case-fatality rate was 15%. Aging populations in warm climates might expect an increasing burden of these infections. 相似文献
995.
Adam Davison Kaspar Gierke Johann Helmut Brandsttter Norbert Babai 《Investigative ophthalmology & visual science》2022,63(3)
PurposeCone photoreceptors of the retina use a sophisticated ribbon-containing synapse to convert light-dependent changes in membrane potential into release of synaptic vesicles (SVs). We aimed to study the functional and structural maturation of mouse cone photoreceptor ribbon synapses during postnatal development and to investigate the role of the synaptic ribbon in SV release.MethodsWe performed patch-clamp recordings from cone photoreceptors and their postsynaptic partners, the horizontal cells during postnatal retinal development to reveal the functional parameters of the synapses. To investigate the occurring structural changes, we applied immunocytochemistry and electron microscopy.ResultsWe found that immature cone photoreceptor terminals were smaller, they had fewer active zones (AZs) and AZ-anchored synaptic ribbons, and they produced a smaller Ca2+ current than mature photoreceptors. The number of postsynaptic horizontal cell contacts to synaptic terminals increased with age. However, tonic and spontaneous SV release at synaptic terminals stayed similar during postnatal development. Multiquantal SV release was present in all age groups, but mature synapses produced larger multiquantal events than immature ones. Remarkably, at single AZs, tonic SV release was attenuated during maturation and showed an inverse relationship with the appearance of anchored synaptic ribbons.ConclusionsOur developmental study suggests that the presence of synaptic ribbons at the AZs attenuates tonic SV release and amplifies multiquantal SV release. However, spontaneous SV release may not depend on the presence of synaptic ribbons or voltage-sensitive Ca2+ channels at the AZs. 相似文献
996.
The Discriminative Stimulus Effects of the Neurotensin NTS1 Receptor Agonist PD149163 in Rats: Stimulus Generalization Testing with Dopamine D1 and D2 Receptor Ligands 下载免费PDF全文
Adam J. Prus Candice J. Schuck Kristoffer R. Rusch Lawrence M. Carey 《Drug development research》2014,75(2):47-58
Preclinical Research |
997.
A haplotype block downstream of plasminogen is associated with chronic and aggressive periodontitis 下载免费PDF全文
Yvonne Jockel‐Schneider Knut Adam Per Hoffman Klaus Berger Thomas Kocher Jörg Meyle Peter Eickholz Christof Doerfer Matthias Laudes André Uitterlinden Wolfgang Lieb Andre Franke Stefan Schreiber Steven Offenbacher Kimon Divaris Corinna Bruckmann Bruno G. Loos Søeren Jepsen Henrik Dommisch Arne S. Schäefer 《Journal of clinical periodontology》2017,44(10):962-970
998.
Patrick Meagher Mohamed Adam Robert Civitarese Antoinette Bugyei-Twum Kim A. Connelly 《The Canadian journal of cardiology》2018,34(5):632-643
Diabetes mellitus (DM) is a major cause of heart failure in the Western world, either secondary to coronary artery disease or from a distinct entity known as “diabetic cardiomyopathy.” Furthermore, heart failure with preserved ejection fraction (HFpEF) is emerging as a significant clinical problem for patients with DM. Current clinical data suggest that between 30% and 40% of patients with HFpEF suffer from DM. The typical structural phenotype of the HFpEF heart consists of endothelial dysfunction, increased interstitial and perivascular fibrosis, cardiomyocyte stiffness, and hypertrophy along with advanced glycation end products deposition. There is a myriad of mechanisms that result in the phenotypical HFpEF heart including impaired cardiac metabolism and substrate utilization, altered insulin signalling leading to protein kinase C activation, advanced glycated end products deposition, prosclerotic cytokine activation (eg, transforming growth factor-β activation), along with impaired nitric oxide production from the endothelium. Moreover, recent investigations have focused on the role of endothelial-myocyte interactions. Despite intense research, current therapeutic strategies have had little effect on improving morbidity and mortality in patients with DM and HFpEF. Possible explanations for this include a limited understanding of the role that direct cell-cell communication or indirect cell-cell paracrine signalling plays in the pathogenesis of DM and HFpEF. Additionally, integrins remain another important mediator of signals from the extracellular matrix to cells within the failing heart and might play a significant role in cell-cell cross-talk. In this review we discuss the characteristics and mechanisms of DM and HFpEF to stimulate potential future research for patients with this common, and morbid condition. 相似文献
999.
Kate Bloom Jaime Adler Christy Bridges Julia Bernstein Christine Rini Adam O. Goldstein Carol Ripley-Moffitt 《The journal of primary prevention》2018,39(4):387-399
Obesity affects more than one-third of Americans and is a leading cause of preventable death. Integrating patient perspectives into obesity treatment can help primary care providers (PCPs) intervene more effectively. In this study, we describe patients’ experiences with PCPs concerning the diagnosis and treatment of obesity and offer suggestions for patient-centered care in weight management. We conducted four focus groups with patients of a university medical system-associated family practice who had a BMI?≥?30. Interview questions addressed general weight management perceptions and preferences for weight management support in a primary care setting. Patients completed a brief demographic survey at the conclusion of the group. Four authors independently coded focus group notes to identify themes and determine saturation using qualitative thematic analysis. We resolved discrepancies by team discussion. Thirty primary care patients participated, of whom 23 were female and whose average age was 50. Twenty-four had attempted to lose weight in the past 12 months and had discussed management with their providers. Analyses identified four themes regarding weight management in a primary care setting: motivation and weight management, the provider–patient relationship, desire for concrete weight loss plans, and limitations of the primary care setting. Motivation was named as a weight management obstacle. Participants felt that PCPs need to be partners in weight management efforts and also recognized limitations of PCP time and expertise. They endorsed an integrated behavioral approach that includes physical activity and nutrition support. Improving PCP delivery of evidence-based treatment for obesity will lead to increased patient attempts to lose weight. Incorporating patients’ desires for concrete plans, ongoing support, and referral to integrated service (e.g., nutritionists, care managers, behavioral health providers) programs can increase patient engagement and success. The chronic disease care and Patient Centered Medical Home models offer guidance for ensuring sustainability of weight management services. 相似文献
1000.