• The Korean Journal of Nuclear Medicine
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• v.16 no.2
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• pp.59-61
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• 1982

To evaluate the diagnostic value of the ratio of serum tyroxine$(T_4)$/thyroxine-binding globulin (TBG) for the thyroid status in pregnancy and newborn serum thyroxine, TBG, triiodothyronine, and free thyroxine levels were radioimmunoassayed in normal pregnant women at each of the trimesters, and the calculated serum $T_4/TBG$ ratios were compared with other parameters such as $T_3/TBG$ ratio and free $T_4/TBG$ ratio and free $T_4/TBG$ ratio. Serum $T_4$ levels were elevated with the propotionate increase in TBG levels during pregnancy, leading to the nearly constant value of serum $T_4/TBG$ ratios as in normal non-pregnant controls. In contrast, serum $T_3/TBG$ and free $T_4/TBG$ ratios varied considerably during pregnancy. In newborn, $T_4$ levels were nearly not changed with compared non-pregnant control value and TBG levels were elevated. The results indicate that serum $T_4/TBG$ ratio is a better parameter than others in evaluating the thyroid status during pregnancy and but newborn is a no better.

• Biomedical Science Letters
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• v.5 no.1
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• pp.11-15
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• 1999

Thyroxine (3,5,3',5'-L-tetraiodothyronine; T$_4$) is the most commonly measured thyroid hermono for the diagnosis of various thyroid disorders. Although radioimmunoassay (RIA) is still considered as the reference technique for the measurement of T$_4$, it is generally regarded that RIA has its primary disadventages in handling the wastes and controling the human and material resources. Therefore, establishment of enzyme-linked immunosorbent assay (ELISA) has of great significance. To verify the usefulness of our enzyme immunoassay, we have obtained the standard dose response curve of T$_4$ in patient's sera which is inversely proportional to the amount of herseradish peroxidase (HRP) conjugated monoclonal antibody of T$_4$ bound to the wells. The correlation coefficient (r) between the ELISA and chemiluminescent assay was 0.444 (n=38). Thus we have investigated the establishment of rapid and sensitive competitive ELISA assay method for detection of T$_4$ in patient's sera.

• Journal of Sasang Constitutional Medicine
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• v.4 no.1
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• pp.193-212
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• 1992

Comparative hormones quantities on the blood analysis was carried out to investigate the hormones specific characters on the blood in four types of physical constitution. Thyroid-stimulating (TSH), triiodothyronine($T_3$), triiodothyronine uptake($T_3$ uptake), free triiodothyronine(free $T_3$), thyroxine($T_4$), free thyroxine (free $T_4$), thyroxine-binding globulin(TBG), adrenocorticotropic hormone(ACTH), luteinizing hormone(LH), testosterone were measured. The results obtained were summarized as follows: 1. The value of thyroid-stimulating hormone(TSH) on the constitution didn't shown significant difference, while the value of So-EUM-IN was increased and SO-YANG-IN was decreased. 2. The value of triiodothyronine($T_3$) on the constitution didn't shown significant difference, while the value of TAE-EUM-IN was decreased. 3. The value of triiodothyronine uptake($T_3$ uptake) on the constitution didn't shown significant difference, but between the value of TAE-EUM-IN and SO-EUM-IN, TAE-EUM-In and SO-YANG-IN showed significant difference. 4. The value of free triiodothyronine(free $T_3$) on the constitution didn't shown signifcant difference, but between the value of TAE-EUM-IN and SO-EUM-In, TAE-EUM-In and SO-YANG-IN showed significant difference. 5. The value of thyroxine($T_4$) on the constitution didn't shown significant difference, while the value of TAE-EUM-IN and SO-YANG-IN showed difference. 6. The value of free thyroxine(free $T_4$) on the constitution didn't shown significant difference, but between the value of TAE-EUM-IN and SO-YANG-IN showed significant difference. 7. The value of thyroxine-binding globulin(TBG) on the constitution didn't shown significant difference. 8. The value of adrenocorticotropic hormone(ACTH) on the constitution didn't shown significant difference. 9. The value of luteinizing hormone(LH) on the constitution didn't shown significant difference, but between the value of TAE-EUM-IN and SO-EUM-IN, TAE-EUM-IN and SO-YANG-IN showed significant difference. 10. The value of testosterone on the constitution didn't shown significant difference.

• Korean Journal of Poultry Science
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• v.17 no.2
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• pp.79-82
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• 1990

An experiment was conducted to evaluate relative biopotency of tri-iodothyronine ($T_3$) and thyroxine ($T_4$) to induce oxygen consumption in young chicks. Four experimental groups of 3 chicks were injected with $T_3$ or $T_4$ at a dose of 500 or 1000mg per kg body weight, and thereafter oxygen consumption was measured by indirect calorimetry using a respiration apparatus. Oxygen consumption was significantly increased at 2 and 4 hour in the $T_3$ or $T_4$ treated chicks at 500mg at 2 hour. From coefficient of a multiple regression equation of oxygen consumption on $T_3$ or $T_4$, it was concluded that $T_3$ was shown to be two to three times as biologically active as $T_4$.

• Korean Journal of Veterinary Research
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• v.39 no.1
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• pp.55-61
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• 1999

The present experiments were performed to examine the effects of acetylcholine (ACh) and carbachol (CC) on thyroxine ($T_4$) release and any possible relation between inhibition of $T_4$ release and signaling pathway in guinea pig thyroids. The thyroids were incubated in the medium containing the test agents, samples of the medium were assayed for $T_4$ by EIA kits. ACh and CC inhibited the TSH-stimulated $T_4$ release. These inhibition were reversed by atropine, but not by d-tubocurarine. The inhibitory effects of ACh on $T_4$ release were prevented by $M_{1^-}$ and $M_{3^-}$muscarinic antagonists and its inhibition was also slightly reversed by $M_{2^-}$ and $M_{4^-}$muscarinic antagonists. R59022, like ACh and CC, also inhibited the TSH-stimulated $T_4$ release. This inhibition was reversed by protein kinase C inhibitor and $Ca^{2+}$ channel blocker. The present study suggests that cholinergic inhibition of $T_4$ release from thyroids can be induced mainly by activation of the $M_{1^-}$ or $M_{3^-}$ receptors and that it is mediated through the muscarinic receptorstimulated protein kinase C activation.

• Journal of radiological science and technology
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• v.10 no.1
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• pp.85-90
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• 1987

Preliminary studies on the measurement of the free thyroxine in the serum with Amerlex $FT_{4}$ RIA kit were investigated using a tracer as $^{125}I-T_{4}$ derivative which is not almostly bound to thyroxine binding globulin, etc. The results are followed: 1. Linearity was tested on standards at various concentrations, and reproducibility and accuracy was excellent. 2. The antibody specificity is also excellent, and standard calibration curve of total $T_{4}$ was similar that of adding the TBG inhibitor. 3. Each value of $T_{4}$ in serum (the normal group, the hypothyroidism patients the pregnant women and the TBG dificiency patients) was not significant. As mentioned above, this method is more simple and rapid, compared to the other method.

• The Korean Journal of Nuclear Medicine
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• v.3 no.2
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• pp.33-38
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• 1969

The serum thyroxine levels were measured by method of Tetrasorb Kit in 69 subjects including 13 subjects in euthyroid state, 31 with hyperthyroidism, 5 with hypothyroidism, 13 with nontoxic diffuse goiter, and 7 with nontoxic nodular goiter. Three parameters of the thyroid function test including thyroxine ($T_4$) levels, $^{131}I$ uptake (24 hrs) values and $PB^{131}I$ conversion ratio were correlated with clinical manifestations and courses of the disease. 1. The serum $T_4$ levels in the normal subjects were in range of $6.0{\mu}g/dl\;to\;14.4{\mu}g/dl$. (The mean $9.4{\mu}g/dl$). 2. The diagnostic compatibility of the serum $T_4$ was 93.5% in hyperthyroidism, 100% both in hypothyroidism and in nontoxic diffuse goiter, 86% in nontoxic nodular goiter, or 95.8% in the entire series. (Table 1). 3. The diagnostic compatibility of $^{131}I$ uptake (24 hrs) values and $PB^{131}I$ conversion ratio were less than the serum $T_4$ levels as summarized in Tables 2 & 3. The serum $T_4$ determination by Tetrasorb Kit is a simple, accurate and very useful test of the thyroid function.

• 대한핵의학회:학술대회논문집
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• 1973.11a
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• pp.52.1-52.1
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• 1973

• Nuclear Engineering and Technology
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• v.7 no.2
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• pp.127-133
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• 1975

For isotopic exchange labelling of 3,5,3'-triiodothyronine (T$_3$) and thyroxine (T$_4$) with radioiodide in the presence of molecular iodine, T$_3$:I$_2$ or T$_4$:I$_2$ molar ratios, pH, and reaction time are. considered to be important factors. A modified labelling and separation method is proposed in present paper, by which T$_3$-$^{125}$ I and T$_4$-$^{125}$ I can be obtained with the mean labelling yields of 45%, and 50%, respectively. The whole reaction products can be separated by adoption of thin-layer chromatography technique using silica gel plate and the solvent system composd of chloroform, methanol and ammonia.

• 대한핵의학회:학술대회논문집
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• 1972.11a
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• pp.73-73
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• 1972