摘要:

Interstitial cells of the rat ovary during pregnancy have been studied by electron microscopy. They show the characteristic fine-structural features associated with steroid-secreting cells. The findings have shown the presence of transitional intermediate stages between theca externa cells and interstitial cells, indicating the possible participation of the theca externa in the formation of interstitial cells.

ISSN:1422-6405    

DOI:10.1159/000145021

出版商:S. Karger AG    

年代:1979

数据来源: Karger

摘要:

The vagal trunci of a series of 31 males and females were investigated and quantitative measurements of vagal fibers were also made from human vagal nerves. Most of the nerves contained fibers of the visceromotor, secretory and sensible type. The posterior vagal nerve contained somatomotor fibers.

ISSN:1422-6405    

DOI:10.1159/000145022

出版商:S. Karger AG    

年代:1979

数据来源: Karger

摘要:

Effects of cyproterone acetate, a synthetic steroidal compound, on the reproductive organs of female rats have been investigated. This agent caused reduction of ovarian weights indicative of suppression of pituitary gonadotrophins. Oestrogenic nature of cyproterone acetate was investigated in intact and ovariectomized rats taking uterine weight and vaginal keratinization as an index of oestrogenicity. Cyproterone acetate in ovariectomized animals induced vaginal keratinization and increased the uterine weights. These effects were parallel to the effect of oestradiol dipropionate in ovariectomized animals, thus indicating oestrogenic activity of cyproterone acetate. We may conclude that the above compound caused antifertility effects due to its oestrogenic nature at the dose level of 2 mg/alternate day in rats when the compound was administered subcutaneously.

ISSN:1422-6405    

DOI:10.1159/000145023

出版商:S. Karger AG    

年代:1979

数据来源: Karger

摘要:

We have studied, by electron microscopy, the ultrastructural aspects of secretion (neurosecretion) of the ependyma of the third ventricle of the domestic cat. We have found cytoplasmic protrusions and isolated masses of cytoplasm, some with homogeneous cytoplasm and others with very dense granulation (protein-β?). Axons, synaptic terminals and free secretory granules in the ventricular lumen were also seen. The existence of ependymin-β cells (ependymo-cyte-β) and axohormonal buttons is suggested. The ependymal cells are classified into seven types: (1) covering ependymocytes, (2) tanycyt ependymocytes, (3) secretory ependymocytes, (4) ependymocytes-β, (5) neurosecretory ependymocytes, (6) neurosensorial ependymocytes (crown-like) and (7) supraependymal microgial ependymocytes. A neurohormonal hypothesis and the possible existence of one or more cerebral hormones (neurohormones) are suggested. These hormones would flow into the CSF through some of the ependymal cells (by microapocrine secretion, liberation of neurosecretion granules, or by axohormonal buttons); this could be the most important link in the endocrine system, assuring the functional unity throughout the ventricular system of the cerebrospinal axis which it winds through, although its basic influence is exercised on the hypophysis level as a vertex of the classical endocrine sys

ISSN:1422-6405    

DOI:10.1159/000145024

出版商:S. Karger AG    

年代:1979

数据来源: Karger

摘要:

The gross anatomy and the internal structure of the marmoset (Callithrix jacchus) brain stem, cerebellum and diencephalon are described based on the observations made on the material obtained from 10 adult animals (native name: sagui). 5 brains were used for gross anatomical observations; the other 5 brains, included in toto in celloidin, were cut into serial sections, properly stained and used for comparative studies of the internal structure. Only general descriptions are given considering this part of the encephalon because, in further papers, it is intended to go on describing in details the nervous system of this small primate, very common in Brazilian jungles and easily domesticated. It shows to be a very good and inexpensive animal for neurophysiological experiments.

ISSN:1422-6405    

DOI:10.1159/000145025

出版商:S. Karger AG    

年代:1979

数据来源: Karger

摘要:

Non-keratinized, stratified squamous epithelium lined the mucosa of the forestomach. The mucosal appendages in the form of ruminal papillae did not develop in the rumen during this study, however, omasal laminae and reticular ribs were evident in groups I and II, respectively. Cytoplasmic accumulations were evident in the middle layer of the epithelium, which is characteristic of this region. The thickness of the epithelium increased constantly in the rumen and reticulum, but in the omasum it remained constant with the increase in the size of the fetus. The corial papillae in the rumen, reticulum and omasum appeared at the 12.7-, 11.5- and 14.6-cm CVR stage, respectively. The muscularis mucosae appeared in the omasum at the 14.6-cm CVR stage in the first-order laminae. The tunica muscularis consisted of spirally arranged muscle fibre bundles. Cross-cut muscle fibre bundles below the tip of the omasal laminae descended downward with the increase in the size of the fetus and continued with the inner circular layer. Acid and alkaline phosphatases and fat could not be observed. The concentration of glycogen in the epithelium was maximum in group III and minimum in group II.

ISSN:1422-6405    

DOI:10.1159/000145026

出版商:S. Karger AG    

年代:1979

数据来源: Karger

摘要:

Retinas of laser-irradiated mice were studied in the first 24 h after irradiation. Decrease in Na+ and K+ concentrations and in phagosome number and increase in pyknotic cells were observed several hours after irradiation.

ISSN:1422-6405    

DOI:10.1159/000145027

出版商:S. Karger AG    

年代:1979

数据来源: Karger

摘要:

The epididymal region of the Japanese quail was studied histologically. The organ consists of the extratesticular portion of the rete testis, the ductuli efferentes proximales and distales, the ducti conjugentes and ductus epididymidis. Distinct tubuli recti link the seminiferous tubules with the rete testis. The non-ciliated cells of the ductuli efferentes proximales and distales show, between them, certain internal structural differences which were highlighted. In 40% of the birds, the ductus deferens showed dark-grey pigments, regarded as melanin. The epididymal region was generally similar in structure to that of the domestic fowl, turkey and duck.

ISSN:1422-6405    

DOI:10.1159/000145028

出版商:S. Karger AG    

年代:1979

数据来源: Karger

摘要:

Histochemical study of the innervation of the heart of the Indian flying fox Pteropus giganteus has been made using Coupland and Holmes’ technique for chohnesterase. Distribution of nerve plexuses in the heart wall has been described. Nerve cells, nerve endings and various types of synapses have been reported. Specialized muscle fibres are found to contain less nerve fibres and conduction of the impulse of contraction is reported to take place through muscle fibre

ISSN:1422-6405    

DOI:10.1159/000145029

出版商:S. Karger AG    

年代:1979

数据来源: Karger

摘要:

Marked differences in the AChE activity of myelinated nerve fibres of ventral and dorsal roots could be established in human post mortem material. After a fixation time of 3 h and a critical incubation period of 24 h, in the mean 96% of the myelinated ventral root but only 4% of dorsal root fibres showed reaction product, detectable by the light microscope. The percentage of stained fibres varies, to some extent, in the different segments. Groups of very thin myelinated fibres within the ventral roots between the segments C-8 and L-3, showing a conspicuous high enzyme activity, are interpreted as pre-ganglionic sympathetic fibres; similar elements in the sacral ventral roots may represent parasympathetic fibres. The method of Karnovsky, applied under conditions established in this study, can be used for analysis of fibre types in a given human peripheral nerve.

ISSN:1422-6405    

DOI:10.1159/000145030

出版商:S. Karger AG    

年代:1979

数据来源: Karger