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排序方式: 共有908条查询结果,搜索用时 31 毫秒
31.
Miriam Prez-Saldívar Graciela Ordoez Benjamín Pineda Julio Sotelo Adolfo Martínez-Palomo Jos Flores-Rivera Martha Espinosa-Cantellano 《International journal of molecular sciences》2022,23(1)
An association between varicella zoster virus (VZV) and multiple sclerosis (MS) has been reported in Mexican populations. The aim of this study was to compare the response of T cells from MS patients, during relapse and remission, to in vitro stimulation with VZV, adenovirus (AV) and Epstein–Barr virus (EBV). Proliferation and cytokine secretion of T cells from 29 relapsing-remitting MS patients and 38 healthy controls (HC) were analyzed by flow cytometry after stimulating with VZV, AV or EBV. IgG and IgM levels against VZV and EBV were quantified using Enzyme-Linked Immunosorbent Assay. Relapsing MS patients showed a higher percentage of responding CD4+ and CD8+ T cells against VZV compared to AV. In HC and remitting MS patients, proliferation of CD4+ T cells was higher when stimulated with VZV as compared to EBV. Moreover, T cells isolated from remitting patients secreted predominantly Th1 cytokines when cell cultures were stimulated with VZV. Finally, high concentration of anti-VZV IgG was found in sera from patients and controls. The results support previous studies of an VZV-MS association in the particular population studied and provide additional information about the possible role of this virus in the pathogenesis of MS. 相似文献
32.
Izchel Figarola-Centurin Martha Escoto-Delgadillo Gracia Viviana Gonzlez-Enríquez Juan Ernesto Gutirrez-Sevilla Eduardo Vzquez-Valls Blanca Miriam Torres-Mendoza 《International journal of molecular sciences》2022,23(2)
HIV-Associated neurocognitive disorder (HAND) is one of the major concerns since it persists in 40% of this population. Nowadays, HAND neuropathogenesis is considered to be caused by the infected cells that cross the brain–blood barrier and produce viral proteins that can be secreted and internalized into neurons leading to disruption of cellular processes. The evidence points to viral proteins such as Tat as the causal agent for neuronal alteration and thus HAND. The hallmarks in Tat-induced neurodegeneration are endoplasmic reticulum stress and mitochondrial dysfunction. Sirtuins (SIRTs) are NAD+-dependent deacetylases involved in mitochondria biogenesis, unfolded protein response, and intrinsic apoptosis pathway. Tat interaction with these deacetylases causes inhibition of SIRT1 and SIRT3. Studies revealed that SIRTs activation promotes neuroprotection in neurodegenerative diseases such Alzheimer’s and Parkinson’s disease. Therefore, this review focuses on Tat-induced neurotoxicity mechanisms that involve SIRTs as key regulators and their modulation as a therapeutic strategy for tackling HAND and thereby improving the quality of life of people living with HIV. 相似文献
33.
Peter T.Cummings Philippe M.Fauchet Michael Goldfarb Martha W.M.Jones Maithilee Kunda Jonathan B.Perlin Nilanjan Sarkar Keivan G.Stassun Zachary E.Warren Karl E.Zelik 《工程(英文)》2021,7(2):141-143,中插10-中插13
1. Background
The use of engineering tools, design, research, and thinking to create environments and capabilities whereby individuals who are currently under-e... 相似文献
34.
Jeffrey Beck Richard Scritchfield Billy Sullivan Jamie Teherani Chang-Feng Wan Mike Kinch Martha Ohlson Mark Skokan Lewis Wood Pradip Mitra Mike Goodwin Jim Robinson 《Journal of Electronic Materials》2009,38(8):1579-1592
The operation of the mid-wave infrared (MWIR) HgCdTe cylindrical electron injection avalanche photodiode (e-APD) is described.
The measured gain and excess noise factor are related to the collection region fill factor. A two-dimensional diffusion model
calculates the time-dependent response and steady-state pixel point spread function for cylindrical diodes, and predicts bandwidths
near 1 GHz for small geometries. A 2 μm diameter spot scan system was developed for point spread function and crosstalk measurements at 80 K. An electron diffusion
length of 13.4 μm was extracted from spot scan data. Bandwidth data are shown that indicate bandwidths in excess of 300 MHz for small unit
cells geometries. Dark current data, at high gain levels, indicate an effective gain normalized dark density count as low
as 1000 counts/μs/cm2 at an APD gain of 444. A junction doping profile was determined from capacitance–voltage data. Spectral response data shows
a gain-independent characteristic. 相似文献
35.
Martha Heller 《IT时代周刊》2007,(24):78
对CIO们而言,制订一个灵活的继任者计划,帮助公司培养未来IT领导人。直接关乎自己职业宏图的拓展。毕竟,在没有得到一个足够优秀的人才来接替你的工作之前,CEO怎么会将你调任到其他新岗位呢? 相似文献
36.
Martha Langford 《History of Photography》2016,40(1):28-48
Canadian photographer Richard Harrington has been recognised since the 1950s for his photographs of the Arctic, and specifically for portraits of the Padleimiut taken at a hunting camp in 1950 during a winter of acute shortages. Three were selected for Edward Steichen’s The Family of Man (1955). Of that group, two focused on motherhood through depictions of childbirth and maternal love; the latter is sometimes referred to as ‘Canada’s Madonna and Child’, making a timeless secular icon from the representation of a crisis. Harrington was a documentary photographer who made his living as a freelance photojournalist specialising in human interest stories and travel features for magazines and newspapers. On assignment in British Columbia for the Hudson’s Bay Company magazine The Beaver, he photographed a First Nations mother and child, an image entitled ‘Madonna of the Peace’. This photograph later graced the cover of a Roman Catholic missionary magazine, Pôle et Tropiques. This article draws parallels between Harrington’s photographs of Indigenous mothers and children and Dorothea Lange’s Migrant Mother, using Harrington’s diaries and community-based research to reconstruct the lives of his subjects, and considering the sacrifice of knowledge to iconicity. 相似文献
37.
Synthesis of nano photocatalysts, LaFeO3 with orthorhombic perovskite structure by sol–gel auto-combustion method was demonstrated. The samples were characterized by PXRD, SEM, HRTEM, XPS and optical absorption studies. Photocatalytic water decomposition over LaFeO3 nanoparticles activated at various temperatures without any co-catalyst were investigated under visible light irradiation (λ >> 420 nm). Highest amount of H2 and O2 evolved in 180 min over the LaFeO3 activated at 500 °C was recorded to be 1290 μmol and 640 μmol, respectively having apparent quantum efficiency (AQE) 8.07%. The pronounced activity of nano LaFeO3 samples towards water decomposition was consistent with BET-surface area and particle size analyses. 相似文献
38.
While the efficacy of PUV-light on microbial inactivation is well documented, its effect on product quality is not well studied. Thus the effect of PUV-light on color, texture and oxidative stability of ham was evaluated. Samples of 100 g raw ham (~5 mm thick) were treated for 60, 90 and 120 s in a UV-light system. Another 100 g of untreated sample was used as a control. The distance from the lamp central axis was varied at 4.5, 8.3 and 14.6 cm. Results showed that the oxidative stability of the control, 4.5 cm/60 s, 4.5 cm/90 s, 4.5 cm/120 s, 8.3 cm/60 s, 8.3 cm/90 s, 8.3 cm/120 s, 14.6 cm/60 s, 14.6 cm/90 s, and 14.6 cm/120 s sample decreased by 21, 67, 53, 54, 39, 71, 75, 56, 58, and 55% respectively after 14 days of storage. Oxidative stability reduction was higher as treatment time was prolonged, but decreased with increased distance from the lamp. Overall, the color and texture of the samples were inversely affected by treatment time and distance of the sample from the lamp. Although PUV-light has a potential to decontaminate food products, this study demonstrated that quality of the product is concurrently compromised. 相似文献
39.
The role of docosahexaenoic acid in retinal function 总被引:3,自引:0,他引:3
Brett G. Jeffrey Harrison S. Weisinger Martha Neuringer Drake C. Mitchell 《Lipids》2001,36(9):859-871
An important role for docosahexaenoic acid (DHA) within the retina is suggested by its high levels and active conservation
in this tissue. Animals raised on n-3-deficient diets have large reductions in retinal DHA levels that are associated with
altered retinal function as assessed by the electroretinogram (ERG). Despite two decades of research in this field, little
is known about the mechanisms underlying altered retinal function in n-3-deficient animals. The focus of this review is on
recent research that has sought to elucidate the role of DHA in retinal function, particularly within the rod photoreceptor
outer segments where DHA is found at its highest concentration. An overview is also given of human infant studies that have
examined whether a neonatal dietary supply of DHA is required for the normal development of retinal function. 相似文献
40.