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11. |
Development of the innervation in the chicken pineal gland (Gallus gallus) |
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Cells Tissues Organs,
Volume 103,
Issue 2,
1979,
Page 212-225
J. Calvo,
J. Boya,
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摘要:
The innervation of the pineal gland has been studied during the embryonic development and the first 10 days after hatching. On day 17 of embryonic development, the first nerve fibers are observed in the pineal capsule. They appear at the stalk level and rise to locate mostly on the anterior side of the capsule. Some nerve fibers leave these nerve bundles to penetrate the gland and they situate in the connective septa (18 days of development). From day 19 of development onwards, nerve fibers locate only in the parafollicular layer. Cells that may be identified as neurons are found in the pineal parenchyma.
ISSN:1422-6405
DOI:10.1159/000145012
出版商:S. Karger AG
年代:1979
数据来源: Karger
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12. |
Helical structure of the human umbilical cord |
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Cells Tissues Organs,
Volume 103,
Issue 2,
1979,
Page 226-230
B.D. Chaurasia,
B.M. Agarwal,
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摘要:
The helical structure of the human umbilical cord has been studied on 528 full-term cords from normal deliveries, 18 cords from aborted and developmentally normal fetuses with a CR length of 1.2–19.5 cm, and 10 cords from monozygotic twins. In order to resolve the discrepancy in the nomenclature of the twist direction, a method has been suggested which takes into account the direction to which the fetus must have rotated to produce the twist. The incidence of the right helical pattern was 64.58%, of the left helical pattern 15.15%, and of the mixed patterns 17.43%; the twists were indeterminate in 1.89% and absent in 0.95% of the cords. Details of the mixed patterns are listed. The number of the uniform right twists ranged from 1 to 29 (7.5) and that of the left twists from 1 to 19 (6.7). There exists an exponential relation between the number of the twists and the ratio between length and thickness of the cords. The twists begin to appear during the early part of the 8th week, and their final number is possibly attained soon after the 9th week of development. In view of the absence of concordance in monozygotic twins, the helical nature of the cord is possibly controlled by factors which may be partly genetic and partly environmenta
ISSN:1422-6405
DOI:10.1159/000145013
出版商:S. Karger AG
年代:1979
数据来源: Karger
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13. |
Histochemical study of the myelin-associated carbohydrates |
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Cells Tissues Organs,
Volume 103,
Issue 2,
1979,
Page 231-237
Luis M. García-Segura,
R. Martinez-Rodriguez,
I. Suarez,
B. Fernandez-Ruiz,
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摘要:
Myelin-associated carbohydrates were studied by means of histochemical techniques in the central nervous system of birds and mammals. Polianions in the surface of myelin and in interfascicular oligodendroglia were detected using histochemical techniques. Glycoproteins were studied by means of concanavalin A. The Con-A-PO-DAB sequence was used. Concanavalin-A-binding sites were detected in oligodendroglia and on the myelin surface. Similar results were observed in both birds and mammals. The processes of the interfascicular oligodendroglia also contain carbohydrates. A close association between the carbohydrates of these glial processes and the myelin surface carbohydrates was demonstrated, and their probable identity is assumed.
ISSN:1422-6405
DOI:10.1159/000145014
出版商:S. Karger AG
年代:1979
数据来源: Karger
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14. |
The primitive course of the internal carotid artery in mammals |
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Cells Tissues Organs,
Volume 103,
Issue 2,
1979,
Page 238-244
Robert Presley,
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摘要:
In all recent mammals the internal carotid artery at the level of the auditory capsule is derived from the embryonic dorsal aorta. In adults of various groups, the artery lies in positions which are classified as medial or promontory. It is shown that these character states arise by a process of differential growth affecting the relative positions of the dorsal aorta and the cochlear promontory. There is no evidence for separate vessels in the embryo which could give rise to non-homologous internal carotid arteries in the two positions. It follows that the concept of a primitive mammalian morphotype with both a medial and a promontory internal carotid artery in the same individual presents a formidable embryological problem. It is recommended that, in the absence of supporting evidence, the widespread current taxonomic and palaeontological use of this hypothetical morphotype should be regarded with suspicion.
ISSN:1422-6405
DOI:10.1159/000145015
出版商:S. Karger AG
年代:1979
数据来源: Karger
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