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排序方式: 共有5110条查询结果,搜索用时 15 毫秒
91.
Lewis H Mervin Ekaterina Mitricheva Nikos K Logothetis Angelo Bifone Andreas Bender Hamid R Noori 《Journal of cerebral blood flow and metabolism》2021,41(4):874
Functional magnetic resonance imaging (fMRI) is an extensively used method for the investigation of normal and pathological brain function. In particular, fMRI has been used to characterize spatiotemporal hemodynamic response to pharmacological challenges as a non-invasive readout of neuronal activity. However, the mechanisms underlying regional signal changes are yet unclear. In this study, we use a meta-analytic approach to converge data from microdialysis experiments with relative cerebral blood volume (rCBV) changes following acute administration of neuropsychiatric drugs in adult male rats. At whole-brain level, the functional response patterns show very weak correlation with neurochemical alterations, while for numerous brain areas a strong positive correlation with noradrenaline release exists. At a local scale of individual brain regions, the rCBV response to neurotransmitters is anatomically heterogeneous and, importantly, based on a complex interplay of different neurotransmitters that often exert opposing effects, thus providing a mechanism for regulating and fine tuning hemodynamic responses in specific regions. 相似文献
92.
A Recessively Inherited Risk Locus on Chromosome 13q22-31 Conferring Susceptibility to Schizophrenia
Tariq Mahmood Mohammed E El-Asrag James A Poulter Alastair G Cardno Anneka Tomlinson Sophia Ahmed Ahmed Al-Amri Jamshid Nazari Joanna Neill Rifka S Chamali Nancy Kiwan Suhaila Ghuloum Hamid A Alhaj Juliette Randerson Moor Shabana Khan Hassen Al-Amin Colin A Johnson Peter Woodruff Iain D Wilkinson Manir Ali Steven J Clapcote Chris F Inglehearn 《Schizophrenia bulletin》2021,47(3):796
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The present study deals with designing and synthesizing novel dyes using the drug combination of edaravone and azo compounds which can be used as an indicator for anions and cations. The desired product synthesis was accomplished via a two-step process involving diazotizing the aromatic amines followed by the resultant salts coupling with edaravone. The resulting dyes were obtained with high yields under mild conditions. The structures of the dyes were identified with UV-vis, FT-IR, 1H NMR and 13C NMR spectra and CHN analysis. To investigate the solvatochromism effect, the interaction of different solvents with the selected dyes was evaluated using several parameters including the dielectric constant, refractive index, hydrogen bond donating ability, hydrogen bond accepting ability and dipolarity/polarizability scale. To achieve deep understanding about the stability and geometrical characteristics of the azo–hydrazo tautomers of the synthesized dyes and their UV-visible spectra prediction, some DFT calculations were also carried out on the synthesized dyes. The antibacterial activities of some synthesized compounds were also evaluated using the disk diffusion method. The results revealed different activity of the selected synthesized dyes for antibacterial tests against selected Gram positive and Gram negative bacteria.The present study deals with designing and synthesizing novel dyes using the drug combination of edaravone and azo compounds which can be used as an indicator for anions and cations. 相似文献
97.
Shannon J Ernst P Yamauchi Y Olivenstein R Lemiere C Foley S Cicora L Ludwig M Hamid Q Martin JG 《Chest》2008,133(2):420-426
BACKGROUND: Some studies of severe asthma suggest that persistence or alteration in the pattern of inflammation may be associated with the severity of the disease. Whether there are differences in the expression of the principal cytokines and chemokines relevant to eosinophilic and neutrophilic inflammation in the airway tissues of severe compared to moderate asthmatics has not been determined. The aim of this study was to compare the patterns of expression of representative T-helper (Th) type 1 (interferon [IFN]-gamma) and Th-2 cytokines (interleukin [IL]-4, IL-5) and the neutrophil- and eosinophil-associated chemokines (IL-8 and eotaxin) in the airway tissues of patients with severe and moderate asthma. METHODS: Subjects with severe asthma (n = 24) and a comparison moderate asthma group (n = 26) were assessed using spirometry, induced sputum, exhaled nitric oxide, and bronchial biopsy. The expression of proteins of interest in the epithelium and subepithelium of the airway wall was examined by immunocytochemistry. RESULTS: Subjects with severe asthma were more symptomatic, had a lower FEV(1), and had more sputum neutrophilia (p = 0.007) and eosinophilia (p = 0.001). Exhaled nitric oxide was similar between groups. IL-8 and IFN-gamma expression were increased and IL-4 expression was decreased in severe asthma compared to moderate disease (p < 0.001 for each comparison). Eotaxin and IL-5 expression did not differ between the groups. CONCLUSION: Patients with severe asthma have increases in neutrophils and eosinophils in the sputum, and differ in airway cytokine/chemokine expression from moderate asthmatics. Excess neutrophilia may be explained by increased expression of IL-8, but differences in eosinophilia do not appear to be associated with IL-5 and eotaxin expression. 相似文献
98.
Seyyed Hamid Hashemi Fariba Keramat Mitra Ranjbar Mojgan Mamani Ali Farzam Shirin Jamal-Omidi 《International journal of infectious diseases》2007,11(6):496-500
OBJECTIVE: To determine the frequency and clinical characteristics of osteoarticular complications of brucellosis in an endemic region in Iran. METHODS: In a prospective study we evaluated 245 patients with brucellosis diagnosed between January 2004 and December 2005. Patients included were those older than 8 years of age and who had clinical features suggestive of brucellosis and specific antibodies at significant titers, and/or positive blood or body fluid culture for Brucella species. A bone scan was performed in those with a clinical suspicion of osteoarticular involvement. RESULTS: Seventy patients (28.6%) had osteoarticular complications. Sacroiliitis was the most common complication (75.7%), followed by spondylitis (21.4%) and peripheral arthritis (8.6%). Spondylitis was the most common osteoarticular complication in the elderly. Relapses occurred in five (2%) patients, three of them with spondylitis. CONCLUSIONS: Osteoarticular disease is the most common complication of brucellosis in Western Iran. Sacroiliitis is the most common form of osteoarticular complication. With the use of a proper treatment regimen, the prospect for recovery is good. 相似文献
99.
We describe a rare giant placental chorioangioma in a patient who had a favorable outcome with close prenatal surveillance in a 28‐year‐old primigravida who was referred to our clinic for ultrasound evaluation of a suspected placental mass at 23 weeks' gestation. A detailed ultrasound scan revealed a well‐circumscribed, echogenic lesion measuring 11.0 × 10.3 × 7.3 cm and protruding into the amniotic cavity. A diagnosis of placental chorioangioma was made and intensive prenatal surveillance was scheduled. A small‐for‐gestational age (2,325 g) but normal female neonate was delivered at 37 weeks by cesarean section and discharged from hospital on the second day of the delivery. A giant chorioangioma may not cause any adverse effect to the fetus and may not require any medication or invasive intervention. © 2014 Wiley Periodicals, Inc. J Clin Ultrasound 43 :254–256, 2015 相似文献
100.