Template:Endocrine embryo table: Difference between revisions
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|+ '''Human Embryonic Endocrine Timeline''' | |||
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| [[Carnegie stage 13|'''Stage 13''']] (week 4) | | [[Carnegie stage 13|'''Stage 13''']] (week 4) | ||
* [[Endocrine - Pituitary Development|Pituitary]] - basement membranes of the craniopharyngeal pouch and the brain are clearly in contact.<ref name= | * [[Endocrine - Pituitary Development|Pituitary]] - basement membranes of the craniopharyngeal pouch and the brain are clearly in contact.<ref name=ORahilly1973>{{Ref-O'Rahilly1973}}</ref> | ||
* [[Endocrine - Thymus Development|Thymus]] - Weller (1933)<ref name=Weller1933>{{Ref-Weller1933}}</ref> recognized already a thymic primordium "of considerable size" on the ventral part of the third pharyngeal pouch, whereas Norris (1938)<ref name=Norris1938>{{Ref-Norris1938}}</ref> considered this stage to be "preprimordial" | * [[Endocrine - Thymus Development|Thymus]] - Weller (1933)<ref name=Weller1933>{{Ref-Weller1933}}</ref> recognized already a thymic primordium "of considerable size" on the ventral part of the third pharyngeal pouch, whereas Norris (1938)<ref name=Norris1938>{{Ref-Norris1938}}</ref> considered this stage to be "preprimordial" | ||
* [[Endocrine - Thyroid Development|Thyroid]] - median thyroid is now bilobed and is connected to the pharynx by a hollow pedicle.<ref name=Weller1933>{{Ref-Weller1933}}</ref> The telopharyngeal body has been regarded as a "lateral thyroid component" by some workers.<ref name=Weller1933>{{Ref-Weller1933}}</ref> | * [[Endocrine - Thyroid Development|Thyroid]] - median thyroid is now bilobed and is connected to the pharynx by a hollow pedicle.<ref name=Weller1933>{{Ref-Weller1933}}</ref> The telopharyngeal body has been regarded as a "lateral thyroid component" by some workers.<ref name=Weller1933>{{Ref-Weller1933}}</ref> | ||
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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<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= | * [[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=ORahilly1973a>{{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.<ref name=Streeter1945>{{Ref-Streeter1945}}</ref> The parathyroid 4 primordium has been illustrated at this stage by Weller (1933, Fig. 16). | * [[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). | ||
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| [[Carnegie stage 16|'''Stage 16''']] (week 6) | | [[Carnegie stage 16|'''Stage 16''']] (week 6) | ||
* [[Endocrine - Pituitary Development|Pituitary]] - slight indication of the infundibular recess may be seen in some embryos.<ref name= | * [[Endocrine - Pituitary Development|Pituitary]] - slight indication of the infundibular recess may be seen in some embryos.<ref name=ORahilly1973a>{{Ref-O'Rahilly1973a}}</ref> | ||
* [[Endocrine - Pineal Development|Pineal]] - cellular migration in an external direction occurs in the pineal body during stages 16 and 17 (Stadium 2 of Turkewitsch)<ref name=Turkewitsch1933>{{Ref-Turkewitsch1933}}</ref><ref name=O'Rahilly1968>{{Ref-O'Rahilly1968}}</ref> | * [[Endocrine - Pineal Development|Pineal]] - cellular migration in an external direction occurs in the pineal body during stages 16 and 17 (Stadium 2 of Turkewitsch)<ref name=Turkewitsch1933>{{Ref-Turkewitsch1933}}</ref><ref name=O'Rahilly1968>{{Ref-O'Rahilly1968}}</ref> | ||
* Thymus - according to Norris (1938)<ref name=Norris1938>{{Ref-Norris1938}}</ref> , "not until the primordium of the parathyroid [3] has been outlined can the remaining portion of the third pouch be recognized, by exclusion, as the primordium of the endodermal thymus". | * Thymus - according to Norris (1938)<ref name=Norris1938>{{Ref-Norris1938}}</ref> , "not until the primordium of the parathyroid [3] has been outlined can the remaining portion of the third pouch be recognized, by exclusion, as the primordium of the endodermal thymus". | ||
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| [[Carnegie stage 17|'''Stage 17''']] | | [[Carnegie stage 17|'''Stage 17''']] | ||
* [[Endocrine - Pituitary Development|Pituitary]] - juxtacerebral wall of the craniopharyngeal pouch is the thicker. The lateral lobes (future infundibular, or tuberal, part) and the anterior chamber (Vorraum) are clearly visible.<ref name= | * [[Endocrine - Pituitary Development|Pituitary]] - juxtacerebral wall of the craniopharyngeal pouch is the thicker. The lateral lobes (future infundibular, or tuberal, part) and the anterior chamber (Vorraum) are clearly visible.<ref name=ORahilly1973a>{{Ref-O'Rahilly1973a}}</ref>The infundibular recess displays a characteristically folded wall, namely the neurohypophysis.<ref name=ORahilly1973a>{{Ref-O'Rahilly1973a}}</ref> | ||
* Thymus - connection of the thymus with the pharynx has been severed.<ref name=Weller1933>{{Ref-Weller1933}}</ref> The thymus is intimately approximated to the cervical duct (ibid.) According to Norris (1937), both third and fourth pouches make contact with the ectoderm, although only the third "receives an increment from the ectoderm". | * Thymus - connection of the thymus with the pharynx has been severed.<ref name=Weller1933>{{Ref-Weller1933}}</ref> The thymus is intimately approximated to the cervical duct (ibid.) According to Norris (1937), both third and fourth pouches make contact with the ectoderm, although only the third "receives an increment from the ectoderm". | ||
* [[Endocrine - Parathyroid Development|Parathyroids]] -parathyroid 4 is attached to the lateral surface of what Weller (1933)<ref name=Weller1933>{{Ref-Weller1933}}</ref> termed the "lateral thyroid component" | * [[Endocrine - Parathyroid Development|Parathyroids]] -parathyroid 4 is attached to the lateral surface of what Weller (1933)<ref name=Weller1933>{{Ref-Weller1933}}</ref> termed the "lateral thyroid component" | ||
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| [[Carnegie stage 18|'''Stage 18''']] (week 7) | | [[Carnegie stage 18|'''Stage 18''']] (week 7) | ||
* [[Endocrine - Pineal Development|Pineal]] - cellular migration in the pineal body forms a distinct "anterior lobe" in which follicles appear (Stadium 3 of Turkewitsch)<ref name=Turkewitsch1933>{{Ref-Turkewitsch1933}}</ref>)<ref name= | * [[Endocrine - Pineal Development|Pineal]] - cellular migration in the pineal body forms a distinct "anterior lobe" in which follicles appear (Stadium 3 of Turkewitsch)<ref name=Turkewitsch1933>{{Ref-Turkewitsch1933}}</ref>)<ref name=ORahilly1973a>{{Ref-O'Rahilly1973a}}</ref> | ||
* Thymus- thymus makes contact with the thyroid gland and contains a series of canals internally (Weller 1933). | * Thymus- thymus makes contact with the thyroid gland and contains a series of canals internally (Weller 1933). | ||
* [[Endocrine - Thyroid Development|Thyroid]] - median thyroid is in contact with "lateral thyroid components"<ref name=Weller1933>{{Ref-Weller1933}}</ref>but others have maintained that the telopharyngeal body should not be regarded as a thyroid component (Bejdl and Politzer 1953). The lobes of the thyroid are "composed of series of continuously communicating solid annectent bars" this is "the earliest stage of the definitive thyroid".<ref name=Weller1933>{{Ref-Weller1933}}</ref> First differentiation occurs in Weller's (1933) "lateral thyroid component," which is beginning to "blend into uniformly constituted thyroid tissue". Weller (1933) illustrated (Fig. 11) a thyroid gland that still showed continuity between its pedicle and the epithelium of the pharynx. | * [[Endocrine - Thyroid Development|Thyroid]] - median thyroid is in contact with "lateral thyroid components"<ref name=Weller1933>{{Ref-Weller1933}}</ref>but others have maintained that the telopharyngeal body should not be regarded as a thyroid component (Bejdl and Politzer 1953). The lobes of the thyroid are "composed of series of continuously communicating solid annectent bars" this is "the earliest stage of the definitive thyroid".<ref name=Weller1933>{{Ref-Weller1933}}</ref> First differentiation occurs in Weller's (1933) "lateral thyroid component," which is beginning to "blend into uniformly constituted thyroid tissue". Weller (1933) illustrated (Fig. 11) a thyroid gland that still showed continuity between its pedicle and the epithelium of the pharynx. | ||
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| [[Carnegie stage 20|'''Stage 20''']] (week 8) | | [[Carnegie stage 20|'''Stage 20''']] (week 8) | ||
* [[Endocrine - Pituitary Development|Pituitary]] - the adenohypophysial epithelium adjacent to the neurohy- pophysis constitutes the beginning pars intermedia.<ref name= | * [[Endocrine - Pituitary Development|Pituitary]] - the adenohypophysial epithelium adjacent to the neurohy- pophysis constitutes the beginning pars intermedia.<ref name=ORahilly1973a>{{Ref-O'Rahilly1973a}}</ref> The walls of the craniopharyngeal pouch bud into the mesenchyme.<ref name=Andersen1971>{{Ref-Andersen1971}}</ref><ref name=Jirasek1980>{{Ref-Jirasek1980}}</ref> | ||
* Thymus - the right and left components are in contact with each other<ref name=Weller1933>{{Ref-Weller1933}}</ref> but are "never completely fused"<ref name=Norris1938>{{Ref-Norris1938}}</ref> <ref name=Siegler1969>{{Ref-Siegler1969}}</ref>). Thymic cortex appears (in stages 20-22) as a result, according to Norris | * Thymus - the right and left components are in contact with each other<ref name=Weller1933>{{Ref-Weller1933}}</ref> but are "never completely fused"<ref name=Norris1938>{{Ref-Norris1938}}</ref> <ref name=Siegler1969>{{Ref-Siegler1969}}</ref>). Thymic cortex appears (in stages 20-22) as a result, according to Norris | ||
(1938), of migration of and covering by "cells derived from the cervical sinus". | (1938), of migration of and covering by "cells derived from the cervical sinus". | ||
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** Adrenal Medulla - Nerve fibres and neuroblasts are first seen in the body of the gland. The paragangtion (M3) cells are beginning to multiply rapidly and, from 30 mm (stage 23) until birth, some are differentiating into chromaffin cells.<ref name=Crowder1957>{{Ref-Crowder1957}}</ref> | ** Adrenal Medulla - Nerve fibres and neuroblasts are first seen in the body of the gland. The paragangtion (M3) cells are beginning to multiply rapidly and, from 30 mm (stage 23) until birth, some are differentiating into chromaffin cells.<ref name=Crowder1957>{{Ref-Crowder1957}}</ref> | ||
|- | |- | ||
| Table Data<ref name=O'Rahilly1983a>{{Ref-O'Rahilly1983a}}</ref> | |||
:Links: {{pineal}} (epiphysis cerebri) | {{pituitary}} (hypophysis) | {{thyroid}} | {{parathyroid}} | {{thymus}} | {{pancreas}} | {{adrenal}} (suprarenal) | |||
| '''References''' | | '''References''' | ||
<references/> | <references/> | ||
|} | |}<noinclude>[[Category:Endocrine]][[Category:Timeline]]</noinclude> | ||
[[Category:Endocrine]][[Category:Timeline]] |
Latest revision as of 11:20, 12 May 2018
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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Table Data[20] | References
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