摘要:

In a series of 52 auditory ossicles, their structure and functional significance were studied, with special reference to the patterns of force transmission. The significance of the different degrees of cavitation in the ossicles as well as their eventual pathological significance are also discussed.

ISSN:1422-6405    

DOI:10.1159/000147306

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

Insulin-like immunoreactive neurons were localized in the cervical, thoracic, lumbar and sacral segments of the monkey spinal cord. Both dorsal and ventral horn cells were labelled. Insulin-like reaction product was localized in the cell nucleus and cytoplasm. Both inner and outer nuclear membranes were labelled. Reaction product appeared to be scattered throughout the nucleoplasm but not within the nucleolus. In the cytoplasm, labelling was mainly localized in the cisternae of rER and saccules of Golgi apparatus. Both proximal and distal dendrites were labelled, the reaction product was closely associated with the parallel arrays of neurotubules. Most of the distal dendrites were postsynaptic to non-labelled axon terminals; however, some were postsynaptic to lightly labelled axon terminals. A labelled dendrite often formed the central element of a synaptic glomerulus with several nonlabelled axon terminals. It is hypothesized that insulin-like substance(s) may be modulating nuclear activities as well as neuro-transmission at the synapse.

ISSN:1422-6405    

DOI:10.1159/000147307

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

Early palatal development in various complete and incomplete forms of cleft lip and/or palate (CLP) was studied from birth to 3 months of age by means of dental casts. Palatal morphology (shape) and dimensions – based on reproducible reference points – were determined in a group of 128 CLP children and 68 normal children who served as controls. Substantial normal palatal growth during the first 3 months of life was observed. Round arch forms changed into oval arch forms. Growth mainly takes place in the sagittal direction (+4 mm) (transverse: +1 mm). Palates of CLP children differed significantly dependent on the type of cleft and whether the cleft was complete or incomplete. Cleft lip and alveolus children and bilateral cleft lip and palate children had more elongated palatal arches, whereas unilateral cleft lip and palate children and cleft palate children had wider palatal arches than the control group. Incomplete clefts differed from the control group in the same direction as their complete cleft forms, though less distinctly. Preoperative orthopedics used in CLP patients does not stimulate growth. On the contrary, it even restricts gro

ISSN:1422-6405    

DOI:10.1159/000147308

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

The proximal tubule of the nephron is subdivided into three structurally and functionally distinct segments, which can be differentiated with the help of special methods. With the aim of producing selective markers for these three portions of the proximal tubule, we raised monoclonal antibodies against the brush border membranes of the rat kidney. Immunohistochemistry was carried out with eleven different monoclonal antibodies to sections of rat kidney and other tissues at the light- and electron-microscopical level. These monoclonal antibodies mainly detect antigens located on the brush border of the proximal tubule, and they allow a distinction between its three segments. However, some antibodies also recognize other portions of the nephron, or even the glomerulus or stromal elements. Sites recognized by the antibodies are not limited to the kidney, but staining is observed on the intestinal brush border, the intralobular ducts of the pancreas, the bile canaliculi of the liver and on the macrophage clusters of the spleen. These antibodies are interesting reagents which can be applied to study biochemical differences between brush border membranes. In addition, they recognize antigenically related sites in other organs with reabsorptive or secretory tasks.

ISSN:1422-6405    

DOI:10.1159/000147309

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

The ultrastructural findings on the kidney cells of the gerbil Meriones crαssus have shown the presence of finger-like projections emerging from the basal part of the epithelial cells of the proximal convoluted tubules into the matrix of the thick basal laminae and that structure like membrane-bound bodies are commonly seen in continuity with these processes. Such findings would give clues for the possible biogenesis of the membrane-bound bodies from the epithelial cells. Such an origin is consistent with the idea that either all or part of the population of membrane-bound bodies is produced by a process of budding off from the basal cell membrane rather than by extension of an intracytoplasmic precursor through the plasma membrane

ISSN:1422-6405    

DOI:10.1159/000147310

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

An ultrastructural cytochemical study of acid phosphatase activity performed in mouse endometrium on the second day of pregnancy showed that stromal cells which were heavily labeled by the cytochemical reaction had disarranged organelles. On the other hand, the cytoplasm of several stromal cells had collagen-containing phagosomes that were also labeled, indicating that the collagen fibrils were being digested by lysosomal enzymes. It is suggested that cell death and phagocytosis of collagen are events of the remodeling of the mouse endometrium that occur prior to decidualization.

ISSN:1422-6405    

DOI:10.1159/000147311

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

The detailed anatomical distribution of iron in the post-mortem human brain has been studied using Perl’s and Turnbull’s methods with the diaminobenzidine intensification procedure for the demonstration of non-haem Fe3+ and Fe2+ respectively. Attention to methodological procedures has revealed that even brief immersion of tissue in routinely used fixatives causes a reduction of staining intensity in areas of high iron content and, often, loss of staining in areas of low iron content. Optimal staining is obtained using frozen section briefly fixed for 5 min in 4% formalin and Perl’s stain (Fe3+) with diaminobenzidine intensification. Highest levels of stainable iron were found in the extrapyramidal system with the globus pallidus, substantia nigra zona reticulata, red nucleus and myelinated fibres of the putamen showing highest staining reactivity. Moderate staining intensity with Perl’s technique was found in the majority of forebrain, midbrain and cerebellar structures with the striatum, thalamus, cortex and deep white matter, substantia nigra zona compacta, and cerebellar cortex showing consistent staining patterns with intensification of Perl’s stain. The brain-stem and spinal cord generally only showed staining with the intensification procedure and even this was of low intensity. Microscopically the non-heam iron appears to be found predominantly in glial cells as fine cytoplasmic granules which in heavily stained areas coalesce to fill the entire cell. Iron-positive granules appear to be free in the neuropil and also around blood vessels in the globus pallidus, striatum and substantia nigra. The neuropil shows a fibrous impregnation when stained for iron which is, in part, derived from glial processes, myelinated fibres and fibre bundles. Neurones, in general, show only very low reactivity for iron, and this is difficult to discern due, often, to the higher reactivity of the surrounding neuropil. In the globus pallidus and substantia nigra zona reticulata, neurones with highly stainable iron content are found with granular cytoplasmic iron reactivity similar to that seen in the local glial cells. Our results are comparable with those of early workers, but with the use of intensification extend the distribution of non-haem iron to areas previously reported as negative. No apparent correlation of iron staining with known neurotransmitter systems is seen and the predilection for the extrapyramidal system is not easily explained, though the non-haem iron in the brain appears to be as a storage form in the iron storage protein ferritin. The localization of iron in the brain provides a foundation for the study of iron in certain neurodegenerative diseases such as Parkinson’s disease, where iron has been implicated in the p

ISSN:1422-6405    

DOI:10.1159/000147312

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

Perichondrial tissue is of great importance as a transplant for the repair of hyaline-cartilage defects of synovial joints because of its potential to produce hyaline-like cartilage. The histological and histochemical character and fiber orientation of rib perichondrial grafts prior to a transplantation procedure for the repair of full-thickness hyaline-cartilage defects is analyzed in a sheep model. Compared to other descriptions of the rib perichondrium of other different species and humans, the perichondrial architecture of different origins demonstrates the same histological, histochemical character and fiber orientation. The three different layers of this tissue are: the outer fibrous layer, the central part called proliferation zone and the inner part towards the underlying rib called transition zone. The fibrous layer demonstrates a wave-like extracellular configuration and contains a few fibrocytes. The proliferation zone is only a few cell rows thick and contains single cells with an oval shape and longitudinal fibrocyte-like nucleus. Because of the potential of these cells to produce cartilage this layer is called proliferation or cambium layer. The transition zone contains more oval-shaped cells with rounded nuclei and demonstrates a more chondrocytic character. Some cells lie in groups of 2 and more cells like in chondrons. The extracellular matrix shows an increasing stain towards the rib cartilage indicating new cartilage production. The fiber orientation is longitudinal in the fibrous part and vertical in the transition zone. Between these layers, fibers deviate from the longitudinal to the vertical orientation corresponding to the light-microscopically visible proliferation zone.

ISSN:1422-6405    

DOI:10.1159/000147313

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

Filiform papillae, which were densely distributed all over the dorsal surface of the lingual body, were crown-shaped, with a central, circular area that sloped in the anterior direction and several branches that surrounded it in a semicircle from the back of the central area. Dome-shaped, fungiform papillae were scattered among these filiform papillae. At the posterior end of the lingual body, there were four circumvallate papillae. Prominent microridges and elevated intercellular borders were widely distributed in the central area of the filiform papillae and the inteφapillar region. On the surface of the branches of the filiform papillae, microridges were rarely seen. On the surface of the fungiform papillae, indistinct microridges were observed. Histologically, the dorsal lingual epithelium revealed three different regions: the epithelium on the anterior side of the filiform papillae, the epithelium on the posterior side of the filiform papillae and the inteφapillar epithelium. Whereas the basal and suprabasal cells are similar throughout, differences characterize the intermediate and surface layers. Keratohyalin granules appear predominantly in the intermediate layer in the epithelium on the anterior side of filiform papillae. In the epithelium on the posterior side of the filiform papillae, no keratohyalin granules occur and, instead, tonofibrils are prominent. The cells become significantly flattened. In the inter-papillar epithelium, no keratohyalin granules are visible, and the tonofilaments occupy almost the entire cytoplasm of most cells in the intermediate and surface layers. The cells are larger in volume in these layer

ISSN:1422-6405    

DOI:10.1159/000147314

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

The colonic microvascularization of 10 adult Sprague-Dawley rats and guinea pigs (Cavia porcellus) was studied by scanning electron microscopy of micro vascular corrosion casts. The tunica muscularis is supplied by branches of the sub-mucosal arteriolar plexus, according to the arrangement of muscle layers, longitudinally and transversally arranged capillaries are distinguished. The mucosal capillaries show a honeycomb pattern and mimic the openings of the mucosal glands. Parallel to the luminal aspect of the large intestine, the mucosal capillary loops often arise from the submucosal arterioles at the most abluminal aspect of the mucosa; however, some arterioles end just subjacent to these capillaries. The submucosal veins are located just subjacent to the capillaries of the lamina propria. The rat and guinea pig colonic vascular architecture revealed no differences, neither did the capillary density in different parts of the large intestine.

ISSN:1422-6405    

DOI:10.1159/000147315

出版商:S. Karger AG    

年代:1992

数据来源: Karger