scholarly journals 1H n.m.r. studies of insulin. Assignment of resonances and properties of tyrosine residues

1985 ◽  
Vol 229 (3) ◽  
pp. 731-737 ◽  
Author(s):  
J H Bradbury ◽  
V Ramesh
Keyword(s):  
Spin Echo ◽  
Double Resonance ◽  
Pulse Sequences ◽  
Crystallographic Data ◽  
Tyrosine Residue ◽  
Tyrosine Residues ◽  
Titration Curves ◽  
Echo Pulse

The assignment of the aromatic 1H n.m.r. resonances of the four tyrosine residues of bovine 2-zinc insulin is reported, based on double resonance techniques, use of Hahn spin echo pulse sequences and examination of specific derivatives nitrated at tyrosines A14 and A19 as well as des-(B26-B30)-insulin. Titration curves of the four tyrosine residues show that residues A14 and B16 have normal pK' values of 10.3-10.6 in solution, consistent with their accessibility to solvent in monomer and dimer in the crystal. Tyrosine residues A19 and B26 have pK' values of 11.4 and exhibit other features in their titration curves that are consistent with limited accessibility to solvent and a nonpolar environment. The meta protons of residues B16 and B26 both observe the titration of a nearby tyrosine residue, probably A19. Interpretation of the n.m.r. data obtained in solution is consistent with the crystallographic data for the monomer and dimer obtained on insulin crystals [Blundell, Dodson, Hodgkin & Mercola (1972) Adv. Protein Chem. 26, 279-402].

5281916 NMR angiography using fast spin echo pulse sequences

1995 ◽  
Vol 13 (1) ◽  
pp. IX
Author(s):  
Richard S Hinks ◽  
Matthew Bernstein
Keyword(s):  
Spin Echo ◽  
Pulse Sequences ◽  
Fast Spin Echo ◽  
Echo Pulse ◽  
Fast Spin

scholarly journals Comparison of dB/dt between EPI and Spin-echo Pulse Sequences

2001 ◽  
Vol 57 (4) ◽  
pp. 444-448
Author(s):  
AKIO OGURA ◽  
TAKAHARU HONGOH ◽  
HIROSHI INOUE ◽  
MASARU YAMAZAKI ◽  
MITSUHARU HIGASHIDA
Keyword(s):  
Spin Echo ◽  
Pulse Sequences ◽  
Echo Pulse

Comparison of breath-hold fast spin-echo and conventional spin-echo pulse sequences for T2-weighted MR imaging of liver lesions.

Radiology ◽  
1995 ◽  
Vol 194 (2) ◽  
pp. 431-437 ◽  
Author(s):  
J N Rydberg ◽  
D J Lomas ◽  
K J Coakley ◽  
D M Hough ◽  
R L Ehman ◽  
...  
Keyword(s):  
Mr Imaging ◽  
Spin Echo ◽  
Pulse Sequences ◽  
Fast Spin Echo ◽  
Breath Hold ◽  
Liver Lesions ◽  
Echo Pulse ◽  
Conventional Spin Echo ◽  
Fast Spin

A mathematical model for signal from spins flowing during the application of spin echo pulse sequences

1988 ◽  
Vol 6 (4) ◽  
pp. 437-461 ◽  
Author(s):  
Grant T. Gullberg ◽  
Margaret A. Simons ◽  
Felix W. Wehrli
Keyword(s):  
Mathematical Model ◽  
Spin Echo ◽  
Pulse Sequences ◽  
Echo Pulse

Characteristics of Incidental Pineal Cysts on Magnetic Resonance Imaging

Neurosurgery ◽  
1989 ◽  
Vol 25 (4) ◽  
pp. 636-640 ◽  
Author(s):  
Jagveer S. Sandhu ◽  
James R. McLaughlin ◽  
Camilo R. Gomez
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Spin Density ◽  
Spin Echo ◽  
Pulse Sequences ◽  
Relaxation Times ◽  
Resonance Imaging ◽  
Characteristic Appearance ◽  
Cystic Changes ◽  
Echo Pulse

Abstract Three patients with different neurological complaints were studied by magnetic resonance imaging. Coincidentally, all studies showed cystic changes within the pineal bodies. These cysts appeared hypointense on T1-weighted, spin-echo pulse sequences and hyperintense on T2-weighted images. Spin-density sequences displayed them as hypointense areas, with relaxation times similar to those of the CSF, suggesting their cystic nature. The increased use of magnetic resonance imaging may result in coincidental imaging of involutional cystic pineal changes of many individuals; their characteristic appearance will allow the differentiation between them and pineal neoplastic conditions.

Superparamagnetic Iron Oxide Hepatic MR Imaging: Efficacy and Safety Using Conventional and Fast Spin-Echo Pulse Sequences

1995 ◽  
Vol 5 (5) ◽  
pp. 566-570 ◽  
Author(s):  
Lawrence H. Schwartz ◽  
Steven E. Seltzer ◽  
Clare M. C. Tempany ◽  
Stuart G. Silverman ◽  
David R. Piwnica-Worms ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Mr Imaging ◽  
Spin Echo ◽  
Pulse Sequences ◽  
Superparamagnetic Iron Oxide ◽  
Fast Spin Echo ◽  
Efficacy And Safety ◽  
Echo Pulse ◽  
Fast Spin

scholarly journals In vivo proton electron double resonance imaging of mice With fast spin echo pulse sequence

2011 ◽  
Vol 35 (2) ◽  
pp. 471-475 ◽  
Author(s):  
Ziqi Sun ◽  
Haihong Li ◽  
Sergey Petryakov ◽  
Alex Samouilov ◽  
Jay L. Zweier
Keyword(s):  
Pulse Sequence ◽  
Spin Echo ◽  
Double Resonance ◽  
Fast Spin Echo ◽  
Resonance Imaging ◽  
Echo Pulse ◽  
Fast Spin

Field-Echo Pulse Sequences Used under Suspended Respiration for Detection of Liver Metastases

1989 ◽  
Vol 30 (3) ◽  
pp. 285-289
Author(s):  
T. Andersson ◽  
R. Nyman ◽  
A. Ericsson ◽  
A. Hemmingsson
Keyword(s):  
Liver Metastases ◽  
Spin Echo ◽  
Pulse Sequences ◽  
Matrix Size ◽  
Fast Mri ◽  
Flash Sequence ◽  
Gastrointestinal Tumours ◽  
Repetition Time ◽  
Echo Pulse ◽  
Spin Echo Sequences

To obtain a fast MRI sequence for detection of liver metastases under suspended respiration, two healthy volunteers were examined with the field echo sequence FLASH, using a large number of repetition times, echo times, flip angles and matrix sizes. The spleen was used to simulate liver metastases and contrast-to-noise ratios between liver and spleen were calculated and the sequence with the highest ratio was considered optimal. The different FLASH sequences were also compared with spin echo sequences using short repetition and echo times. A FLASH sequence with a repetition time of 140 ms, an echo time of 14 ms, a flip angle of 80 to 100 degrees and a matrix size of 128×256 was considered the most suitable for detecting liver metastases. This sequence, together with other FLASH and spin echo sequences, were used for examination of five patients with liver metastases from endocrine gastrointestinal tumours.

Sign in / Sign up

Export Citation Format

Share Document