塩化と静止:人間の成長のモデル
M Lampl1, J D Veldhuis, M L Johnson
1Department of Anthropology, University of Pennsylvania, Philadelphia 19104.
まとめ
人間の成長は,絶え間なくではなく,急激に発生します. 幼児の長さは0.5-2.5cmの爆発的に増加し,成長の無い期間と交差し,安定した発達に関する伝統的な見解に異議を唱えます.
科学分野:
- 小児の成長と発達について
- 人間の生理学 人間生理学
- 発達生物学 発達生物学について
背景:
- 伝統的なモデルでは,人間の成長は,年齢に関連した速度の変化を伴う継続的なプロセスとして見ています.
- 幼児の成長は,しばしば安定した線形的な進行として描かれます.
研究 の 目的:
- 最初の21ヶ月間における人間の乳児の長さの増長パターンを調査する.
- 乳児の成長が連続的なプロセスなのか,または離散的なイベントで起こるのかを判断する.
主な方法:
- 33人の正常な乳児 (19人の女性,12人の男性) の連続長さの測定は21ヶ月間にわたって収集されました.
- 測定頻度は,毎週 (n=10),半週 (n=18) および毎日 (n=3) であった.
主要な成果:
- 乳児の長さの成長は不連続で,不定期的な塩突発で発生することが判明しました.
- これらの成長突起の幅は0.5から2.5cmの範囲であった.
- 成長の急増は,測定可能な成長のない2日から63日の間隔で隔てられていた.
結論:
- 乳児の長さの増殖は,静止状態の期間を区切る漸進的な爆発によって特徴づけられる塩分処理プロセスです.
- 赤ちゃんの正常な発達の約90~95%は,成長期間の間隔で起こります.
- これは,継続的な成長モデルに挑戦し,初期の人間の発達における明確な急増ベースのパターンを強調しています.
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