ISSN:1422-6405    

DOI:10.1159/000146603

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

The enumeration of the cranial nerves is traced briefly from Galen’s seven to Willis’ ten and to von Söm-merring’s twelve. The system of von Sömmerring, which has been followed for some 200 years, is a useful convention, although it is merely one of several possibilities. The naming of the cranial nerves was standardized nearly 100 ye

ISSN:1422-6405    

DOI:10.1159/000146604

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

In gastrulae of Xenopus laevis, various morphological types of intercellular approximation occur between the dorsal ectoderm and chordamesoderm. Ruthenium red staining reveals that in some areas the glycocalyces of heterotypic cells appear to come into contact. These observations, in conjunction with the results of previous studies, suggest that cell contacts offer a possible pathway for the transmission of inductive stimuli, and that they may be important in the regionalisation of the neuralised ectoderm.

ISSN:1422-6405    

DOI:10.1159/000146605

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

The relationship between the intactness of sustentacular (Sertoli) cell tight junctions and the status of spermatogenesis was examined in rats fed a vitamin-A-deficient diet after weaning (VAD rats). Both serum and testicular retinol concentrations of the VAD rats declined to a nadir by 80 days of age. At this time, it was observed that Sertoli cell tight junctions of the VAD animals were intact and complete spermatogenesis was maintained. Leakage in Sertoli cell tight junctions, as demonstrated by the presence of lanthanum in the adluminal compartment of the seminiferous epithelium, was first observed in 90-day-old VAD rats. Severe regression of spermatogenic cells was noted in 100-day or older VAD animals. These results suggest that severe germ cell loss observed during chronic vitamin A deficiency may result from abnormal intratubular environment due to the disruption of the blood-testis barrier.

ISSN:1422-6405    

DOI:10.1159/000146606

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

Caprine hemal nodes were studied by light microscopy after glutaraldehyde fixation and epoxy resin embedding. Anode consisted of a capsule, subcapsular and other sinuses, cortex, medulla and hilus. Elements of circulating blood filled the interstices of the reticular meshwork and associated macrophages which traversed the lumina of subcapsular and medullary sinuses. The latter were rare in 1-month-old goats, progressively increased in number and size in 2- to 4-month-old goats and coalesced with each other and the subcapsular sinus in adult animals. The cortical tissue appeared as lymphoid nodules. Circumferential lymphatic vessels abutted on outer margins of the nodules and gave origin to several radial lymphatics which branched and anastomosed between the medullary blood sinuses. Medullary cords were organized around the radial lymphatics. A single efferent lymphatic was formed at the hilum by confluence of the radial lymphatics. Our study, in contrast to earlier reports, shows that caprine hemal nodes possess efferent lymphatics. The present data suggest that the hemal nodes are involved, in addition to classical functions, in blood storage by hemoconcentration.

ISSN:1422-6405    

DOI:10.1159/000146607

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

Scanning-electron-microscopic examination of corrosion casts was used to investigate the microcirculation of the coronary border of the equine hoof. Numerous peg-shaped capillary plexuses derived from arterioles extended distally from the dorsal branches of the digital arteries parallel to the hoof wall. The plexuses varied in length and consisted of a fine network of interconnected capillaries that converged to join a centrally situated venule. These centrally situated venules within the papillary plexuses gave rise to a vast venous plexus deep to the coronary band.

ISSN:1422-6405    

DOI:10.1159/000146608

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

The activities in mouse retinae were evaluated after 6-hydroxydopamine injection. A significant increase in labeled leucine uptake was evident in the photoreceptor layer. Latex uptake in the pigment epithelium showed no changes. Denervation of catecholaminergic terminals inside the retinae thus affected the metabolism of photoreceptors.

ISSN:1422-6405    

DOI:10.1159/000146609

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

A three-dimensional angiographic analysis ofthe deep palmar arterial arches and their correlating arteries in Cercopithecidae, Pongidae and Hominidae revealed the following features. In Cercopithecidae, 3 deep palmar arches are formed by the perforating branches of the 2nd dorsal metacarpal artery: 2 proximal arches (the catella volaris proximalis and the arcus volaris profundus) and 1 distal arch (the catella volaris distalis). The intermetacarpal arteries arise from the catella volaris proximalis and the palmar metacarpal arteries arise from the arcus volaris profundus. In Pongidae, the arches are formed by the perforating branches of the 1st dorsal metacarpal artery, and they are composed of only the catella volaris proximalis and catella volaris distalis. In Hominidae, the arches are formed by the perforating branches of the 1st dorsal metacarpal artery, and they consist of the arcus volaris profundus and an incomplete catella volaris distalis.

ISSN:1422-6405    

DOI:10.1159/000146610

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

Medial menisci, obtained at autopsy, were sectioned into radial segments which were stained in bulk using a modified gold chloride method following pretreatment with Triton X-100. Segments were then sectioned on a sliding microtome at 100 µm, mounted on slides, dehydrated and coverslipped. Axons were seen penetrating from the perimeniscal tissue into the outer third of the meniscus with a heavier concentration at the horns. Neural elements were identified in the perimeniscal tissue and in the outer and middle thirds of the meniscus, but not in the inner third. The medial meniscus is capable of afferent input to the central nervous system of importance to the biomechanical function of the joint

ISSN:1422-6405    

DOI:10.1159/000146611

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

Palatal rugae began to develop in the mouse, before the elevation of the palatal shelves, as localized regions of epithelial proliferation and thickening. Subsequently, fibroblasts and collagen fibres accumulated in the connective tissue subjacent to the thickened epithelium and later assumed a distinctive orientation, the fibres running anteroposteriorly within the core and in concentric curves across the base of each ruga. The role of collagen in rugal morphogenesis was examined after inhibiting its formation by feeding the lathyritic agent β-aminopropionitrile to pregnant females. This substance markedly affected the eventual height of the rugae at birth, confirming the importance of collagen in rugal development

ISSN:1422-6405    

DOI:10.1159/000146612

出版商:S. Karger AG    

年代:1988

数据来源: Karger