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971.
C Snehalatha A Ramachandran V Mohan H Timothy M Viswanathan 《Hormones et métabolisme》1986,18(6):391-394
Pancreatic beta cell function was assessed by estimation of fasting and post prandial plasma C-peptide in 183 non-insulin dependent diabetic patients, who were treated with oral hypoglycaemic drugs, for more than 10 years. One-hundred-and-forty-one patients, continued to respond to oral hypoglycaemic agents (Group I) and in 42 the control was not satisfactory and had to be changed over to insulin (secondary failure, Group II). Significant beta cell reserve (PP CP greater than or equal to 0.6 pmol/ml) was present in 89 out of 183 patients (48%) and 83 (93%) of them responded to oral hypoglycaemic agents. Among the 94 patients with low beta cell reserve, 58 (62%) were on oral hypoglycaemic agents and the other 36 (38%) were on insulin. Of the 42 patients with secondary failure to the oral drugs, 36 (86%) had low C-peptide while 6 (14%) had significant C-peptide values. Secondary failure to oral hypoglycaemic agents can also occur in spite of good beta cell reserve. Beta cell reserve was not correlated either to the duration of diabetes or the age at diagnosis of the patients. 相似文献
972.
Summary The paper presents the results of measurements on tea samples collected during 1962 and 1973–1983 period for their natural radioactivity content. The radioisotopes studied under this programme are radium-226, thorium-228, and potassium-40. Tea was found to contain higher concentration of these radionuclides compared to other foodstuffs having vegetative origin. Interpretation for higher concentrations in tea compared to other foodstuffs is briefly given on the basis of agroclimatic conditions. 相似文献
973.
The structure of tambuletin, present in seeds of Xanthoxylum species has been confirmed as the 8-glucoside of gossypetin 7,4′-dimethyl ether. 相似文献
974.
975.
N-Terminal analysis of purified buffalo thyroglobulin by the fluorodinitrobenzene method of Sanger yielded about 1.5 moles of DNP-glutamic acid per mole of buffalo thyroglobulin. No water-soluble DNP-amino acid was detectable as N-terminal. The presence of glutamic acid has been confirmed by Edman degradation and characterization of the PTH-amino acid in different solvent systems, and also after regeneration of free amino acid from PTH-amino acid in butanol-acetic acid-water (4:1:5, v/v) system. This is in contrast to the occurrence of aspartic acid or asparagine as N-terminals for several other mammalian thyroglobulins. 相似文献
976.
977.
R. Evertz K.R. Ramachandran J.P.R. Herrman L.R. van der Wieken 《Netherlands heart journal》2005,13(12):461-463
Hypothermia can cause several ECG changes which can be mistaken for other cardiac diseases, most importantly acute transmural ischaemia. These ECG changes correlate strongly with the degree of hypothermia and the prognosis of the patient. This brief report presents a 32-year-old male who was seen after a drowning accident. After resuscitation a 12-lead electrocardiogram showed changes typical for hypothermia: atrial fibrillation and Osborn waves. The ECG of the patient normalised after rewarming. 相似文献
978.
G.W. Kenner S. Moore K.L. Ramachandran R. Ramage G.J. Dockray R.A. Gregory L. Hood M. Hunkapiller 《Bioorganic chemistry》1981,10(2):152-160
The synthesis of the tetracontapeptide corresponding to a revised sequence for porcine big gastrin is described. Both the synthetic and natural material were identical by radioimmunoassay using L33 antiserum, which is specific for the N-terminal region of the sequence. 相似文献
979.
The essential role of tyrosine residue(s) of cardiotoxin II in the biological activity of the toxin was evaluated using N-bromosuccinimide.
N-bromosuccinimide effected oxidation of the tyrosine residues in cardiotoxin II with enhancement in absorbance at 260 nm.
The influence of various solvent media such as acetate-formate buffer (pH 4.0), 0.01 N H2SO4 (pH 2.0) and Tris-HCl buffer (pH 8.5) on oxidation of tyrosine residues was exa mined. In comparison with 0.01 N H2S O4, acetate-formate buffer could prevent secondary oxidations as revealed by lower consumption of oxidant, N-bromosuccinimide,
to achieve oxidation. In Tris-HCl buffer oxidation of tyrosine did not take place effectively. N-iodo-succinimide caused only
limited oxidation as evident from minor increase in absorbance at 260 nm. N-chlorosuccinimide was completely ineffective.
Oxidation of cardiotoxin II with 3.75 equivalents of N-bromosuccinimide tyrosine residue led to complete loss of lethal activity.
However, the derivative retained the ability to protect bacterial protoplasts from lysis in solutions of low tonicity. Unlike
cardiotoxin II oxidized with N-chlorosuccinimide (50 equivalents/mol of toxin) which retained lethal activity as well as the
ability to protect protoplasts from lysis, performic acid-oxidized toxin had lost both the activities. 相似文献
980.
H Kawauchi K Muramoto J Ramachandran 《International journal of peptide and protein research》1978,12(5):318-324
The isolation of adrenocorticotropin (ACTH) from fin (Balaenoptera physalus), sei (Blaenoptera borelis) and sperm (Physeter catodon) whale pituitaries is described. Their primary structures have been elucidated by the fluorescein isothiocyanate method and revealed to be identical to the structure of the human hormone. Fin whale exhibited an identical steroidogenic activity to that of the porcine hormone. 相似文献