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991.
Fiona M. Fennessy Andriy Fedorov Sandeep N. Gupta Ehud J. Schmidt Clare M. Tempany Robert V. Mulkern 《Magnetic resonance imaging》2012
There are many challenges in developing robust imaging biomarkers that can be reliably applied in a clinical trial setting. In the case of dynamic contrast-enhanced (DCE) MRI, one such challenge is to obtain accurate precontrast T1 maps for subsequent use in two-compartment pharmacokinetic models commonly used to fit the MR enhancement time courses. In the prostate, a convenient and common approach for this task has been to use the same 3D spoiled gradient-echo sequence used to collect the DCE data, but with variable flip angles (VFAs) to collect data suitable for T1 mapping prior to contrast injection. However, inhomogeneous radiofrequency conditions within the prostate have been found to adversely affect the accuracy of this technique. Herein we demonstrate the sensitivity of DCE pharmacokinetic parameters to precontrast T1 values and examine methods to improve the accuracy of T1 mapping with flip angle-corrected VFA SPGR methods, comparing T1 maps from such methods with “gold standard” reference T1 maps generated with saturation recovery experiments performed with fast spin-echo (FSE) sequences. 相似文献
992.
Sheokand Sandeep Kumar Prashant Jabeen Shakra Samra Kawaljeet Singh 《Journal of Solid State Electrochemistry》2023,27(3):727-738
Journal of Solid State Electrochemistry - In the present work, the effect of reaction temperature and urea concentration on the electrochemical performance of NiO nanoparticles is investigated. The... 相似文献
993.
Sunil Dattatray Chakave Shrikant Shete Dr. Sandeep Reddy Kandukuri Dr. Mark Montgomery Dr. Bhanu N. Manjunath Dr. Ravindra Punjaji Sonawane 《European journal of organic chemistry》2023,26(5):e202201205
The first total synthesis of des-hydroxy triticone A and B was achieved in 12 steps. The highly chemoselective, base mediated iodolactamization of olefins with N-OMe amide motif is a key highlight of the synthesis. 相似文献
994.
Khairnar Akshada Lohidasan Sathiyanarayanan Dubey Rahul Sankaran Sandeep 《平面色谱法杂志一现代薄层色谱法》2023,36(1):63-70
JPC – Journal of Planar Chromatography – Modern TLC - People all over the world are affected by the chronic, disabling autoimmune illness known as rheumatoid arthritis (RA). Herbal... 相似文献
995.
Moriyuki Sato Kazunori Yamauchi Makoto Handa Kuninobu Kasuga 《Macromolecular rapid communications》2000,21(17):1234-1237
Intramolecular cyclization of precursor polyhydrazides derived from hydrazine and four 2,5‐dialkoxyterephthalic acids by direct polycondensation with Lawesson's reagent afforded new conjugated polymers constituted of 1,3,4‐thiadiazole and 2,5‐dialkoxybenzene units. The polymers emitted bluish green light in solution and green light in solid state in spite of the coexistence of non‐cyclized hydrazide linkage in the backbones, the Stokes shifts being 91–138 nm in the solid state. It was suggested that these polymers have appropriate lengths of conjugation backbones based on the 1,3,4‐thiadiazole moiety. 相似文献
996.
Deepshikha Yadav Shilpi Verma Jyoti Choudhary Harleen Kaur Pratibha Tiwari Sandeep Singh Pallavi Kushwaha Premshankar K. Dubey Pranjal Chandra Surinder P. Singh 《Electroanalysis》2023,35(4):e202200286
Folic acid (FA) deficiency is associated with several clinical conditions such as megaloblastic anemia, neuropsychiatric, and pregnancy-related syndromes, this makes FA an important metabolite to be monitored. We have fabricated an electrochemical biosensor based on gold nanoparticles decorated molybdenum disulfide nanosheets (AuNPs−MoS2NSs) nanocomposite as a transducer matrix for specific and rapid electrochemical detection of FA. Differential pulse voltammetry (DPV) studies displayed a rapid analytical response of the fabricated AuNPs−MoS2NSs/GCE sensor probe towards FA in a wide concentration range of 0.001–100 μM with a very low detection limit of 0.72±0.03 nM. The selectivity of the fabricated sensor probe has been examined in the presence of interferents such as dopamine, uric acid, ascorbic acid, glucose, and urea. The clinical potential of the fabricated biosensor was established by monitoring FA in human serum samples. The developed AuNPs−MoS2NSs/GCE sensor probe showed high reproducibility and stability, indicating its promise for FA detection in clinical settings. 相似文献
997.