Preface |
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xv | |
Acknowledgements |
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xix | |
List of Figures |
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xxi | |
List of Tables |
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xxxiii | |
List of Abbreviations |
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xxxv | |
1 General Introduction |
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1 | (12) |
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1 | (4) |
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2 Physiology of the HPT Axis |
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5 | (1) |
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2.1 Synopsis of Thyroid Biochemistry and Molecular Biology |
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5 | (2) |
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2.2 Operation of the Hypothalamus-Pituitary (HP) System |
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7 | (1) |
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8 | (1) |
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2.4 Physiological Feedback Representation of the HPT System |
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8 | (2) |
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10 | (3) |
3 Modeling Principles |
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13 | (22) |
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13 | (2) |
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15 | (6) |
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15 | (6) |
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3.3 Electrical Network Representation of the Leaking Water Container |
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21 | (3) |
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24 | (2) |
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3.5 Modeling Examples from Solid-state Physics and Electronic Engineering |
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26 | (2) |
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3.6 General Appearance and Decay Model with Electrical Network Elements |
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28 | (2) |
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3.7 Appearance Time Constant |
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30 | (1) |
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3.8 Determining the Value of the Appearance Time Constant |
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31 | (1) |
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32 | (1) |
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33 | (1) |
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34 | (1) |
4 Medical Statistics and Mathematical Modeling Make Strange Bedfellows |
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35 | (12) |
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35 | (1) |
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4.2 Pitfalls in the Application of Inferential Statistical Methods |
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36 | (5) |
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4.2.1 Explanation of the Observed Log-linear Relationship between [ TSH] and [ FT4] |
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40 | (1) |
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4.3 Abuse of Mathematical Models |
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41 | (2) |
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41 | (2) |
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43 | (1) |
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44 | (1) |
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45 | (2) |
5 Systems Theory Applied on the Modeling of the HPT Axis and First Principles of Feedback and Homeostasis |
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47 | (24) |
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47 | (7) |
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5.2 Definition of System Components |
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54 | (4) |
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58 | (3) |
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5.4 Frequency Response of the First-order Low-pass Section |
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61 | (3) |
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5.5 Cascading System Blocks |
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64 | (1) |
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5.6 Example of a Feedback System |
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64 | (5) |
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5.6.1 Feed Forward Compensation |
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68 | (1) |
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69 | (1) |
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69 | (2) |
6 The Mathematical Relationship between [ FT4] and [ TSH] |
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71 | (22) |
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71 | (4) |
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71 | (4) |
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6.2 Linear-logarithmic Relationship between [ FT4] and [ TSH] |
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75 | (5) |
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6.3 Modeling the Curved [ FT4]-[ TSH] Characteristic |
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80 | (3) |
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6.4 Properties of the Exponential Function |
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83 | (4) |
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6.4.1 Effect of the Multiplier Model Parameter S |
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84 | (1) |
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6.4.2 Effect of the Exponential Model Parameter phi |
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85 | (2) |
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6.5 Dynamic Signal Transfer of the HP Characteristic |
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87 | (1) |
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6.6 Generalized Expression of the HP Characteristic |
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88 | (1) |
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89 | (1) |
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90 | (3) |
7 The Thyroid Gland and the Relationship Between [ TSH] and [ FT4] |
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93 | (6) |
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93 | (1) |
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7.2 Model of the Thyroid Gland |
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94 | (3) |
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97 | (1) |
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98 | (1) |
8 The Hypothalamus-Pituitary (HPT) Set Point Theory |
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99 | (36) |
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99 | (1) |
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8.2 The Hypothalamus-Pituitary (HP) Control System |
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100 | (2) |
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8.3 Derivation of the Point of Maximum Curvature from the HP Function |
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102 | (2) |
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8.4 Theory Behind of the Physiology of the Homeostatic Control Process |
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104 | (1) |
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8.5 Point of Maximum Curvature of the Thyroid Characteristic |
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105 | (2) |
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107 | (1) |
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108 | (3) |
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9 The Human Hypothalamus-Pituitary-Thyroid Control System |
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111 | (1) |
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111 | (3) |
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9.2 Analysis of the HP Unit and Thyroid in the Closed-Loop Situation |
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114 | (5) |
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9.3 Small-Signal Model of the Thyroid |
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119 | (1) |
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9.4 Small-Signal Modeling of the Hypothalamus-Pituitary (HP) Unit |
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120 | (1) |
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121 | (3) |
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9.6 Hypothalamus (TRH)-Pituitary (TSH) Transfer |
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124 | (3) |
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9.7 The Detailed HPT Loop |
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127 | (1) |
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9.8 Large-Signal Intercept Set Point |
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128 | (3) |
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131 | (1) |
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132 | (3) |
10 Reference Ranges for TSH and FT4 |
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135 | (10) |
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135 | (1) |
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10.2 Reference Ranges for [ FT4] and [ TSH] |
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136 | (2) |
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10.3 Set Point Determined Euthyroid Ranges for [ TSH] |
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138 | (1) |
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10.4 Different Reference Ranges in Different Laboratories |
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139 | (3) |
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142 | (1) |
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143 | (1) |
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144 | (1) |
11 Extrapolation to the Set Point from a Single Available Measurement |
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145 | (30) |
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145 | (1) |
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11.2 Calculation of [ FT4] Assuming a Pre-determined Set Point Value of [ TSH] |
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146 | (3) |
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11.3 Calculation of [ TSH] Assuming a Set Point Value of [ FT4] = 15 pmol/L |
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149 | (1) |
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11.4 Extrapolation to a Set Point Using a "Phantom" [ FT4]-[ TSH] Point |
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150 | (4) |
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154 | (3) |
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12 Measurement Methods, Error Sources, and Error Interpretation of FT4 and TSH Concentration Values |
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157 | (1) |
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157 | (3) |
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12.2 Error Definitions and Error Sources |
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160 | (1) |
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161 | (1) |
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12.4 [ FT4] and [ TSH] Measurement or Thyroid Function Tests (TFTs) |
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162 | (1) |
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12.5 Sensitivity of Model Parameter phi as a Function of [ FT4] and [ TSH] |
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163 | (1) |
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12.6 Measurement Errors from [ FT4] Rounding or Truncation Procedure |
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163 | (2) |
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12.7 Absolute Deviation of [ FT4] as a Function of Relative [ TSH] Error |
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165 | (1) |
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12.8 The Effect of Absolute Errors in [ FT4] Resulting in Deviations of [ TSH] |
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166 | (1) |
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12.9 Errors from Physiological Memory Effects, or Hysteresis |
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167 | (2) |
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12.10 Errors from Biochemical Assay Technology for [ TSH] and [ FT4] |
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169 | (2) |
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171 | (1) |
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172 | (1) |
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173 | (2) |
13 Model Identification, Validation, and Outlier Selection |
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175 | (12) |
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175 | (2) |
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13.1.1 A Brief History of Celestial Modeling as a Prelude to Model Validation |
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175 | (2) |
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13.2 Model Identification |
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177 | (5) |
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13.3 Examples of [ TSH], [ FT4], and [ FT3] Outlier Identification |
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182 | (1) |
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183 | (1) |
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184 | (3) |
14 Half-Life and Plasma Appearance Dynamics of T3 and T4 |
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187 | (20) |
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187 | (1) |
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14.2 Half-Life (t1/2) of T4 and Calculation of the Decay Time Constant |
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188 | (4) |
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14.2.1 Half-Life Modeling with Electrical Networks |
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190 | (2) |
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14.3 Drug Input and Output Signals |
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192 | (9) |
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197 | (4) |
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14.4 Decay Behavior after Finalization of Drug Appearance |
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201 | (4) |
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205 | (1) |
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206 | (1) |
15 Pharmacokinetics of Liothyronine (L-T3) and Levothyroxine (L-T4) |
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207 | (26) |
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207 | (2) |
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209 | (2) |
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15.2.1 PK of L-T4 with T4 Level Dependent and Constant t1/2 When Administered as a Daily Dose |
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209 | (1) |
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15.2.2 Derivation of the Steady-State Level |
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209 | (2) |
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15.3 Average Value of Time-Dependent Functions |
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211 | (1) |
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15.4 RMS Value of Continuous Time-Dependent Functions |
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212 | (1) |
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15.5 Weekly Administration of L-T4 at Seven Times the Normal Daily Dose |
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213 | (2) |
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15.6 Triiodothyronine Kinetics |
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215 | (3) |
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15.6.1 Accumulation of T3 Based on Various Dosages of Daily Liothyronine (L-T3) |
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215 | (1) |
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15.6.2 Accumulation of T3 over a Period of 9 days with a Daily Dose Dd of 12.5 microg L-T3 |
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215 | (3) |
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15.7 Compensation Strategies When L-T4 Is Not Taken Regularly |
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218 | (6) |
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15.7.1 Acceleration Toward Steady State for a 100 microg L-T4 Daily Dosing Scheme Within 1 Week |
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218 | (6) |
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15.8 Calculation of a Reduced Dosing Scheme |
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224 | (1) |
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15.9 Negative Long-term Effects of Externally Administered T3 |
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225 | (1) |
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226 | (2) |
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228 | (2) |
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230 | (3) |
16 Circadian Feedback Dynamics and Set Point Stability Analysis of the Hypothalamus Pituitary Thyroid System |
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233 | (22) |
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233 | (2) |
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235 | (3) |
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16.3 Influence of [ FT4] and [ TSH] on Feedback Dynamics |
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238 | (2) |
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240 | (1) |
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240 | (4) |
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244 | (3) |
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16.7 Convolution and Deconvolution |
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247 | (1) |
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248 | (1) |
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248 | (2) |
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250 | (2) |
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252 | (1) |
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252 | (3) |
17 HPT Simulation with Trans-linear Circuits |
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255 | (24) |
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255 | (2) |
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17.2 Generalized Stimulated Gland Characteristics |
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257 | (3) |
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17.3 Large-signal Intercept Set Point |
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260 | (3) |
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17.4 Differential Amplifiers |
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263 | (4) |
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17.5 Trans-linear Circuits |
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267 | (3) |
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267 | (2) |
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17.5.2 Examples of Signal Processing with Trans-linear Circuits |
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269 | (1) |
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17.6 HPT Functions with Trans-linear Circuits |
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270 | (2) |
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17.7 The Electronic HP System Implementation |
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272 | (1) |
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17.8 The Electronic Thyroid Implementation |
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273 | (2) |
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275 | (1) |
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276 | (3) |
18 From Theory to Practice: Computer-aided Set Point Application |
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279 | (10) |
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279 | (1) |
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18.2 Thyroid-SPOT Software |
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280 | (2) |
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18.3 Clinical Studies Using Thyroid-SPOT |
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282 | (1) |
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18.4 Thyroid-SPOT (Set Point Optimization and Targeting) |
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283 | (2) |
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18.5 Thyroid Function Tests |
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285 | (2) |
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18.6 Interpretation of Test Results |
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287 | (1) |
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288 | (1) |
Appendix |
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289 | (4) |
Index |
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293 | (6) |
About the Authors |
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299 | |