Template:Endocrine embryo table: Difference between revisions
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| [[Carnegie stage 14|'''Stage 14''']] (week 5) | | [[Carnegie stage 14|'''Stage 14''']] (week 5) | ||
* [[Endocrine - Pineal Development|Pineal]] - a slight irregularity in the surface outline of the intact head corresponds to the future pineal body (O'Rahilly et al. 1982). | * [[Endocrine - Pineal Development|Pineal]] - a slight irregularity in the surface outline of the intact head corresponds to the future pineal body (O'Rahilly et al. 1982). | ||
* [[Endocrine - Pituitary Development|Pituitary]] - craniopharyngeal pouch is prominent | * [[Endocrine - Pituitary Development|Pituitary]] - craniopharyngeal pouch is prominent<ref name=Streeter1945>{{Ref-Streeter1945}}</ref> and the notochord appears to be inserted into its dorsal wall. The craniopharyngeal pouch has become elongated and blood vessels are beginning to grow in between the basement membranes of the pouch and brain.<ref name=O'Rahilly1973a>{{Ref-O'Rahilly1973a}}</ref> | ||
* [[Endocrine - Thyroid Development|Thyroid]] - thyroid pedicle shows further elongation but is still connected to the epithelium of the pharynx.<ref name=Weller1933>{{Ref-Weller1933}}</ref> Right and left lobes and an isthmus may perhaps be presaged (ibid.). | * [[Endocrine - Thyroid Development|Thyroid]] - thyroid pedicle shows further elongation but is still connected to the epithelium of the pharynx.<ref name=Weller1933>{{Ref-Weller1933}}</ref> Right and left lobes and an isthmus may perhaps be presaged (ibid.). | ||
* [[Endocrine - Parathyroid Development|Parathyroids]] - "Parathyrogenic zones" <ref name=PolitzerHann1935>{{Ref-PolitzerHann1935}}</ref> are recognizable | * [[Endocrine - Parathyroid Development|Parathyroids]] - "Parathyrogenic zones" <ref name=PolitzerHann1935>{{Ref-PolitzerHann1935}}</ref> are recognizable.<ref name=Streeter1945>{{Ref-Streeter1945}}</ref> The parathyroid 4 primordium has been illustrated at this stage by Weller (1933, Fig. 16). | ||
* [[Endocrine - Thymus Development|Thymus]] - Weller's (1933)<ref name=Weller1933>{{Ref-Weller1933}}</ref> "thymus" (the third pharyngeal pouch) becomes elongated. | * [[Endocrine - Thymus Development|Thymus]] - Weller's (1933)<ref name=Weller1933>{{Ref-Weller1933}}</ref> "thymus" (the third pharyngeal pouch) becomes elongated. | ||
* Pancreas - ventral pancreas (which may perhaps be distinguishable as early as stage 13) appears as an evagination from the bile duct at stages 14<ref name=Blechschmidt1973>{{Ref-Blechschmidt1973}}</ref> and 15 | * Pancreas - ventral pancreas (which may perhaps be distinguishable as early as stage 13) appears as an evagination from the bile duct at stages 14<ref name=Blechschmidt1973>{{Ref-Blechschmidt1973}}</ref> and 15.<ref name=Streeter1948>{{Ref-Streeter1948}}</ref> It is generally described as unpaired but, at least in some cases, may perhaps be bilobed<ref name=Odgers1930>{{Ref-Odgers1930}}</ref> or even multiple (Delmas 1939). | ||
* [[Endocrine - Adrenal Development|Adrenal]] | * [[Endocrine - Adrenal Development|Adrenal]] | ||
** Adrenal Cortex - A change in the characteristics of the cells of the coelomic epithelium appears between the mesogastrium and the lateral end of the mesonephros.<ref name=Crowder1957>{{Ref-Crowder1957}}</ref> | ** Adrenal Cortex - A change in the characteristics of the cells of the coelomic epithelium appears between the mesogastrium and the lateral end of the mesonephros.<ref name=Crowder1957>{{Ref-Crowder1957}}</ref> | ||
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** Adrenal Cortex - dorsal part of the whole suprarenal primordium is disorganized by the invasion of sympathetic nerves and cells, while the band of C2 cells and the coelomic epithelium remain intact (Crowder 1957). | ** Adrenal Cortex - dorsal part of the whole suprarenal primordium is disorganized by the invasion of sympathetic nerves and cells, while the band of C2 cells and the coelomic epithelium remain intact (Crowder 1957). | ||
** Adrenal Medulla - first neural migration is at its height. Growth of the para-aortic complex is extensive. The plexiform complex is derived from paravertebral sympathetic ganglia T6-12 and usually L 1. Included in it are the primordia of the suprarenal medulla and of the celiac, superior mesenteric, and renal plexuses. Nerve fibres and "paraganglion" (M3) cells enter. | ** Adrenal Medulla - first neural migration is at its height. Growth of the para-aortic complex is extensive. The plexiform complex is derived from paravertebral sympathetic ganglia T6-12 and usually L 1. Included in it are the primordia of the suprarenal medulla and of the celiac, superior mesenteric, and renal plexuses. Nerve fibres and "paraganglion" (M3) cells enter. | ||
* Pancreas - ventral pancreas has now fused with dorsal | * Pancreas - ventral pancreas has now fused with dorsal.<ref name=Streeter1948>{{Ref-Streeter1948}}</ref> Perhaps the ventral and dorsal ducts have begun to blend (Russu and Vaida 1959). | ||
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| [[Carnegie stage 18|'''Stage 18''']] (week 7) | | [[Carnegie stage 18|'''Stage 18''']] (week 7) |
Revision as of 14:28, 1 November 2016
Human Embryonic Endocrine |
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Data based on data from O'Rahilly (1983).[1] |
Stage 13 (week 4)
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Stage 14 (week 5)
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Stage 15
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Stage 16 (week 6)
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Stage 17
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Stage 18 (week 7)
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Stage 19
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Stage 20 (week 8)
(1938), of migration of and covering by "cells derived from the cervical sinus".
Weller (1933, Fig. 23) showed parathyroid 3 still rostral to parathyroid 4 at 23 mm, whereas (presumably due to variation in the "descent" of the thymus) (Norris 1937, Fig. 4[16]) showed parathyroid 3 rostral to, level with, and caudal to parathyroid 4 in embryos of 16-17 mm. |
Stage 21
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Stage 22
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Stage 23
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References
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