نتایج جستجو برای: نانو زئولیت naa

تعداد نتایج: 18897  

Journal: :AJNR. American journal of neuroradiology 2005
Jill V Hunter Robert J Thornton Zhiyue J Wang Harvey S Levin Garland Roberson William M Brooks Paul R Swank

BACKGROUND AND PURPOSE Proton MR spectroscopy has demonstrated reduced levels of N-acetylaspartate (NAA) in normal-appearing occipital and frontal regions of patients with acute nonpenetrating traumatic brain injury (TBI). We studied the relationship of frontoparietal NAA, choline (Cho), and creatine (Cr) to test the hypothesis that reduction in NAA is predictive of cognitive outcome. METHODS...

Journal: :AJNR. American journal of neuroradiology 2010
S L Wootton-Gorges M H Buonocore R A Caltagirone N Kuppermann N S Glaser

Recent data suggest that DKA may contribute to cognitive impairment in children with type 1 DM. We measured the NAA/Cr ratio in a teenager during and following 2 separate episodes of DKA without clinically apparent cerebral edema. The NAA/Cr ratio decreased during DKA and improved following recovery. However, the NAA/Cr value was lower after the second episode of DKA (1.76) than after the first...

Journal: :AJNR. American journal of neuroradiology 1998
S G Pavlakis D Lu Y Frank A Wiznia D Eidelberg T Barnett R A Hyman

Two children with acquired immunodeficiency syndrome (AIDS) and progressive encephalopathy underwent MR spectroscopy before and after antiretroviral therapy. Initial MR spectroscopy of the basal ganglia region showed decreased N-acetylaspartate (NAA)/creatine (Cr) and a lactate peak. After therapy, there was improvement in NAA/Cr and an absence of the abnormal lactate peak. We suggest that decr...

Journal: :GSC Advanced Research and Reviews 2022

The experiment was conducted to study the response of summer onion N2 and Naphthalene Acetic Acid (NAA). consisted two factors. Factor A: 4 levels Nitrogen viz. N0-0kg (control), N1-90kg ha-1, N2-110kg ha-1 N3-130kg B: NAA H0-0ppm, H1- 50ppm, H2-100ppm H3-150ppm. laid out in Randomized Complete Block Design with three replications. Results revealed that terms nitrogen, highest bulb diameter (4....

Journal: :AJNR. American journal of neuroradiology 2000
A A Capizzano N Schuff D L Amend J L Tanabe D Norman A A Maudsley W Jagust H C Chui G Fein M R Segal M W Weiner

BACKGROUND AND PURPOSE Subcortical ischemic vascular dementia is associated with cortical hypometabolism and hypoperfusion, and this reduced cortical metabolism or blood flow can be detected with functional imaging such as positron emission tomography. The aim of this study was to characterize, by means of MR imaging and 1H MR spectroscopy, the structural and metabolic brain changes that occur ...

2017
Ruiting Chang Zuojun Geng Qingfeng Zhu Zhenhu Song Ya Wang

INTRODUCTION To characterize the contents of choline (Cho), creatine (Cr) and N-acetylaspartylglutamate (NAA) in the hippocampus of healthy volunteers, we investigated the contents and their correlationship with age, gender and laterality. MATERIAL AND METHODS Volunteers were grouped into a young, a middle and an old age. The Cho, Cr and NAA contents were determined with proton magnetic reson...

2010
Eun Joo Park Katarina P. Lyra Hae Won Lee Paulo Caramelli Maria C. G. Otaduy Claudia Costa Leite

Prior studies have reported hippocampal volume loss, decrease in N-Acetylaspartate (NAA) concentration and increased myo-inositol (mI) concentration in patients with Alzheimer's disease (AD). The purpose of this study was to evaluate hippocampal volumes of AD patients and their correlation with metabolic changes detected by proton spectroscopy (1H MRS) of hippocampal formations and the posterio...

2014

Introduction Neutron activation analysis (NAA) is a nuclear process used for determining the concentrations of elements in a vast amount of materials. NAA relies on excitation by neutrons so that the treated sample emits gamma-rays. It allows the precise identification and quantification of the elements, above all of the trace elements in the sample. NAA has applications in chemistry but also i...

ژورنال: شیمی کاربردی 2012
حسین طولابی محمد رضا شهدادی میثم صادقی, میر حسن حسینی

در این تحقیق، زئولیت NaY مولکولارسیو به روش هیدروترمال تهیه شد. سپس یون‌های نقره در زئولیت NaY با استفاده از نقره نیترات AgNO3و روش تبادل یونی برای تهیه زئولیتAgY جایگزین گردیدند. در مرحله بعدی، نانو ذراتمنگنز دی اکسید( به عنوان مهمان) به میزان 3/9 و 8/15 درصد وزنی در زئولیت AgY (به عنوان میزبان)با استفاده از محلول‌های M‏n(NO3)2 و KMnO4 به روش سنتز فضای محدود(CSS) تهیه شدند. نمونه‌های سنتز شد...

2017
D. D. Clarke S. Greenfield E. Dicker L. J. Tirri

A detailed time study of the incorporation of label from sodium-[lC]acetate, [1C]ethanol, and [2C]glucose into the aspartyl moiety of N -acetylaspartic acid (NAA) was conducted. As expected the specific activity of aspartate increased rapidly with time and peaked within 15 20 min after which it fell sharply: but significant!). that of the aspartyl moiety of NAA rose very slowly even after the s...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید