摘要:

Testosterone propionate accelerates the maturation of acinar cells in the preputial gland of female rats. The weight of the preputial gland was increased significantly and the gland contained a large amount of secretory material. Various stages of maturation of acinar cells were observed. In an early stage, cells contained predominantly rough endoplasmic reticulum. In a second stage, lipid accumulated in association with focal areas of smooth endoplasmic reticulum. Membrane-bound dense bodies similar to lysosomes and secondary lysosomes predominated in a late stage. In the final stage, acini fused with a duct, thereby liberating the cells into the ductal lumen. Cell structure then became unrecognizable.

ISSN:1422-6405    

DOI:10.1159/000144580

出版商:S. Karger AG    

年代:1976

数据来源: Karger

摘要:

Different eye anomalies, e.g. open eye (lid-gap), exophthalmos, cataractous lens, anophthalmia, microphthalmia, corneal opacities and absent lens were induced in rat fetuses by maternal administration of cyclophosphamide on the 12–16th days of gestation. 63–90% of anomalies were found in groups treated between days 13 and 15 of gestation. The 14th day of gestation was found to be the most susceptible, inducing severe eye anomalies in 90% of fetuses treated at this age. Degenerative changes were seen in the lens and retina. The retinal cytoarchitecture was completely disorgani

ISSN:1422-6405    

DOI:10.1159/000144581

出版商:S. Karger AG    

年代:1976

数据来源: Karger

摘要:

Using antisera to synthetic luteinizing hormone-releasing factor (LRF) and antisera labeled with fluorescein isothiocyanate or peroxidase, it was possible in various physiological and experimental conditions to determine the topography of the LRF secretory cells in the guinea pig. The axons of these cells form a preoptico-infundibular LRF pathway, which controls the prehypophyseal gonadotropic secretion, and various ‘extrahypophyseal pathways’. These latter suggest that LRF, in addition to its prehypo-physiotropic action, may also have a neuromodulator funct

ISSN:1422-6405    

DOI:10.1159/000144582

出版商:S. Karger AG    

年代:1976

数据来源: Karger

摘要:

After a critical review of the literature, the authors describe the structure of the lung of Sphenodon, dealing with form, arteries, veins, and septation. The external form, circulatory pattern, degree of complication, height of the septa, vascular structure, and decrease in complication (?) are discussed from the standpoint of comparative anatomy. In an attempt to explain the unusual findings, the capacity for development of the central and subpleural type of differentiation is compared and contrasted. Obvious relations between the unusual lung structure and the phylogenetic age of the Sphenodon were sought, with the conclusion that the Sphenodon cannot be included in the Reptilian oders since its physical structure forms a class by itself.

ISSN:1422-6405    

DOI:10.1159/000144583

出版商:S. Karger AG    

年代:1976

数据来源: Karger

摘要:

Fibroblasts cultivated in vitro were observed during mitosis. Already after 24 h of culture in 80% oxygen, some anomalies affect mitosis (atypical mitosis): abnormalities of the usual mitosis stages, chromosomal aberrations. Mitosis is interrupted at metaphase during the first and second day of culture in hyperoxia and at prophase (prometaphase) during the third day. A new mode of nuclear division is discussed.

ISSN:1422-6405    

DOI:10.1159/000144584

出版商:S. Karger AG    

年代:1976

数据来源: Karger

摘要:

A histological and histochemical study of the pineal gland of neonatal, juvenile and adult gerbils is described. Calcified inclusions appear within pinealocytes in the superficial pineal about the third week of age, and the incidence of inclusions increases with age until, by the eleventh week, they are found in all animals. The inclusions contain an organic matrix composed of a carbohydrate, probably an acid mucopolysaccharide, complexed to protein. Calcification does not occur in the deep pineal. The data are interpreted to indicate that the formation of calcified inclusions is a normal process within the gerbil pineal. The similarity of the process of calcification in the gerbil and in the human pineal suggests that the gerbil may be the animal of choice for the controlled study of the phenomenon of pineal calcification.

ISSN:1422-6405    

DOI:10.1159/000144585

出版商:S. Karger AG    

年代:1976

数据来源: Karger

摘要:

Paucity of electron-microscopic studies on the fate of endogenous heme iron, released as a result of planned surgery, in the central nervous system warranted the present work. During investigations of neuronal plasticity in the cat, an experimental model, in which the proximal cut end of the vagosympathetic trunk was rerouted into the diencephalon, presented an ideal substrate for studying this problem. At 3 months, the brain tissue containing the implant was processed for light and electron microscopy and histo-chemistry. Under light microscopy, Prussian-blue-positive, dense cytoplasmic aggregates were visible within the macrophages. The cells were mostly clustered around the junctional area between the central and peripheral nerve elements. Electron-microscopic findings were highly characteristic and distinguished the macrophages from the surrounding neural elements by their rich content of electron-dense granules. While the latter were mostly scattered as free cytoplasmic particles, large aggregates of the same were also observed inside the lysosomes. Besides, a few inclusions were seen within astrocytic processes, close to the plasma membranes. At higher magnifications, the particles revealed the characteristic internal subunit structure of ferritin micelles. The uptake of hemoglobin and its subsequent conversion to ferritin within the macrophages and astrocytic processes are discussed at subcellular level in the light of other available studies.

ISSN:1422-6405    

DOI:10.1159/000144586

出版商:S. Karger AG    

年代:1976

数据来源: Karger

摘要:

The surface epithelium and stromal elements in the ovary of the rhesus monkey were studied with a variety of fluorescence-histochemical procedures to determine the relative distribution of specific chemical moieties. The surface (germinal) epithelium displayed high levels of cytoplasmic RNA and specifically intense fluorescence with methods that demonstrate basic, SH and SS groups of protein. The underlying basement membrane demonstrated an intense reaction when fluorochromed with hydroxynaphthoic acid hydrazide directed toward side-chain carboxyl groups of protein. The fluorescence pattern displayed by the underlying connective tissue was heterogeneous and related to its anatomical localization. It is suggested that this heterogeneity reflects specific, but as yet undefined, chemical differences in the fibrous elements of the ovary.

ISSN:1422-6405    

DOI:10.1159/000144587

出版商:S. Karger AG    

年代:1976

数据来源: Karger

摘要:

The urethral process of the goat was an extension of the pars spongiosa of the male urethra. The erectile (cavernous) tissue of the urethral process was a continuation of the corpus spongiosum penis. The epithelium lining the urethra was stratified transitional. Two compact fibrocartilaginous strands were embedded in the erectile tissue, which were absent towards the tip of the urethral process. Smooth muscle was absent in the tunica mucosa-submucosa of the urethral process. The tunica mucosa-submucosa was richly supplied with blood vessels and nerves and it may be assumed that the urethral process is a sensory structure. Large cavernous sinuses, within the erectile tissue, were lined by endothelial cells. There was a circular fibroelastic layer enclosing the entire corpus spongiosum penis to withstand expansion of the erectile tissue during erection and copulation. The surface epithelium lining the urethral process was stratified squamous. A few connective tissue papillae were observed evaginating into the surface epithelium.

ISSN:1422-6405    

DOI:10.1159/000144588

出版商:S. Karger AG    

年代:1976

数据来源: Karger

摘要:

Light and electron microscopic investigations on the Mg++- and Ca++-activated ATPase of sheep and goat dorsal root ganglion have been carried out. Reaction products occur on plasma membranes and interfaces between neurons and sheath cells, between adjacent sheath cells and on the surface of unmyelinated fibers. Cytoplasmic protrusions of ganglion cells and numerous surface increasing invaginations of sheath membranes form close connections between neurons and sheath cells.

ISSN:1422-6405    

DOI:10.1159/000144589

出版商:S. Karger AG    

年代:1976

数据来源: Karger