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PubMedDate not supplied

[Various aspects of the vessels of the renal glomerulus seen through the scanning electron microscope].

The kidney glomeruli of the rabbit have been examined by means of repletion with celloidin and subsequent corrosion. The observation has been done with a scanning electronic microscope. In their most general and common aspect, the glomeruli have variations in their arteries; in some cases these are homogenous whilst in others they may be different within a single glomerulus and different among each other. When the glomeruli are dissected, these differences are seen much better as there can be seen to be several collaterals, those emerging from the afferrent trunk which may have different devices and several shapes as some are more or less elongated whilst in other circumstances these arteries are spiral with numerous curls. We cannot specify whether these differences are purely morphological or different functional states. When glomeruli are observed in a single area, they present different shapes and sizes which suggests that these differences are typical of each glomerulus and never dependent upon the topography where they are located. The arteries of the glomeruli are generally arranged in lobules. These may be different in the size, length and arrangement of the vessels since, as we clearly state in this paper, the vascular lobules are different from each other within a single glomerulus.

Animals↗

PubMed1992

[Identification of morphology and inorganic elements of Eucommia ulmoides Oliv. produced in Sichuan by applying scanning electron microscope with energy dispersive X-ray analysis].

A research on the identification of morphology and inorganic elements of Eucommia ulmoides produced in Sichuan has been made by applying scanning electron microscope; energy dispersive X-ray analysis. Qualitative and semi-quantitative analyses of the inorganic elements in the observed areas have been obtained.

Calcium↗

PubMed1988

The effects of differing acid concentrations, techniques and etch time on the etch pattern of enamel of erupted and unerupted human teeth examined using the scanning electron microscope.

The effects of varying acid concentration, etch time and agitation, on the etch properties of enamel from unerupted and erupted human teeth, were examined using the scanning electron microscope. Results showed that whilst there are differences in behaviour between erupted and unerupted enamel when conditions are varied, under most circumstances unerupted enamel will behave in a similar manner to erupted enamel. With low acid concentration both the duration of etch and agitation seem to be important factors in producing a roughened surface. It is suggested that the manufacturers' recommendations be more precise for a new low acid concentration orthodontic bonding package.

Acid Etching, Dental↗

PubMed1985

A scanning electron microscopic study of chromosomes and nuclei.

The fine structure of metaphase chromosomes and nuclei were studied by scanning electron microscopy. A coiled-coil structure of chromosomes was suggested by hypotonically unravelled chromosomes observed under light microscope. But chromosome preparations made for the light microscopic studies were not adequate for detailed examination with scanning electron microscope. Surface-spread chromosomes revealed that they were composed of nodular, twisted looping fibers of about 300 A in diameter. Surface-spread nuclei were also composed of fibers identical to the chromosome fibers.

Animals↗

PubMed1985

Scanning electron microscope study of cat and dog enamel structure.

Scanning electron microscopy revealed several similarities as well as significant differences in the enamel structure between cat and dog teeth. Three enamel layers were present in both species; a surface rodless (aprismatic) layer, an outer layer of parallel rods (only at some sites), and an inner layer with prominent Hunter-Schreger bands. In the inner layer of both carnivores, the diameter of individual rods varied significantly and frequently their course changed abruptly with respect to neighboring rods. In dog teeth the cross-sectional shape of inner enamel rods was pleomorphic, but hexagonal in outer enamel. In contrast, cat enamel rods were rounded in both inner and outer enamel layers. Hunter-Schreger bands of cats circumscribed the teeth in relatively straight segments, but these bands showed pronounced waviness in dog teeth. In cats and dogs the surface rodless layer was structurally continuous with subjacent interrod enamel and covered all tooth surfaces with the exception of the cervical areas. The data show that the structure of inner and outer enamel layers differ between these two carnivore species and that the enamel structure of the cat was most similar to that described in humans. One principal difference between carnivore and human teeth is that the growth lines of carnivores do not terminate at perikymata on the tooth surface.

Animals↗

PubMed1986

A scanning electron microscopic study of fissured tongue.

In this study, scanning electron microscopy was used to describe the surface morphology of fissured tongue. Tissue samples from the anterior part of the tongue were taken from 15 patients with fissured tongue. The formalin-fixed samples were processed routinely for scanning electron microscopy. Typically, the surface of a fissured tongue was covered with hairless papillae of various sizes. The biggest papillae were larger than the body of a normal filiform papilla, and the apex was rounded and rough. On the other hand, some of these papillae had a few hairs and resembled normal filiform papillae, but were flatter. In addition some papillae formed only slight elevations on the tongue mucosa, which was smooth and contained some desquamating cells. The walls of the fissure found in macroscopical examination consisted of very low elevations of the smooth mucosa with some desquamating cells. At high magnification the superficial cells of the epithelium were polygonal. On their surface there were branching or parallel microplicae, which were often broken. Only occasionally superficial cells of the large papillae had a pitted appearance. The knob-like structures found among the microplicae and small cracks between the epithelial cells are discussed from the standpoint of the pathogenesis of fissured tongue.

Adult↗

PubMed1987

A comparative scanning electron microscopic view of the integument of domestic mammals.

Scanning electron microscopy (SEM) demonstrates efficiently species-specific differences of hairy skin (integumentum commune) of domestic mammals (pig, cat, dog, horse, cattle, sheep, goat). This technique is very helpful in characterizing the typical structural features of the epidermal layers, the arrangement of the collagen fibre bundles and the elastic fibre network in the dermis, the external and internal construction of hair follicles and hair shafts, and the functional development of skin glands. It is also possible to observe certain domestication effects, especially where the hair coat is concerned. SEM supplements the knowledge about the integument as available from conventional transmission electron microscopy, light microscopy or histochemistry. Thus, comparative morphology can be the basis for the development of specific functional models of the different integumentary layers and derivatives or their tissues involved.

Animals↗

PubMed1977

Scanning electron microscopical study of human mitral valve chordae tendineae.

Scanning electron microscopy was used to examine the surface and internal structure of adult human mitral valve chordae tendineae. The endocardial cell surface of the tissue was found to be relatively smooth and even. Just beneath the endocardial surface, widely spaced collagen fibers were found. These were observed to be aligned at an angle to the chordal long axis and to wrap themselves around the central collagen core. The chordal core consisted of relatively straight collagen fibers that were arranged with their axis parallel to the long axis of the chordae. At the microstructural level, these collagen fibers were observed to consist of a network of collagen fibrils. This architectural arrangement is an advantageous feature for a tissue that is under constant dynamic stress. The scanning observations were confirmed by transmission electron microscopy.

Chordae Tendineae↗

PubMed1988

Hypohidrotic ectodermal dysplasia: a genealogic, stereomicroscope, and scanning electron microscope study.

This is a report of three patients with hypohidrotic ectodermal dysplasia, or Christ-Siemens-Touraine syndrome, their genealogic backgrounds and the stereomicroscope and scanning electron microscopic appearances of the hair, the skin of their fingertips and palms as well as skin studies of members of their families. The skin morphology was recorded by means of silicone monomer rubber impressions and epoxy resin dyes. In two of the patients the disease was acquired by X-linked inheritance, while in the third, a boy, it appeared to follow an autosomal dominant pattern. Defects of the skin of the fingertips and palms of the propositi and members of the families included abnormalities of the morphology and pattern of the epidermal ridges, reduction of sweat pores varying from 13 to 87% of normal, and changed anatomy of the openings of the sweat glands. The openings were shallow and with less whorling compared to the normal, funnel-shaped sweat pores. Among the sweat pores, micropores, or openings with an average diameter of 5.3 micrometers, were observed. One of the propositi and the affected father of another had orifices on their fingertips resembling hair sheaths. Two propositi and the affected father of one exhibited grooving of the hair. The findings confirm the necessity for genealogic investigations in patients with or suspected of having the disease in order to advise parents or prospective parents. They also illustrate the usefulness of stereomicroscopy and scanning electron microscopy in observing skin and hair abnormalities.

Child↗

PubMed1982

The effects of castration on size and appearance of Sharpey's fibers of rat femurs: a scanning electron microscopic and microradiographic study.

Areas of Sharpey fiber bone from the proximal posterior diaphyseal surfaces of anorganic control and castrate osteopenic rat femurs were examined with the scanning electron microscope (SEM). The diameter of Sharpey fiber bundle insertion sites from castratre bone was significantly greater (P less than 0.001) than that from control bone. The fiber bundle insertions appeared as small pits and projections in control bone and as large pits in castrate bones. Microradiographs of cross sections of the Sharpey fiber bone revealed a greater (P less than 0.05) area of outer, lamellated periosteal bone in the castrates than in the controls, suggesting an accelerated bone apposition rate along castrate osteopenic femoral periosteal surfaces.

Animals↗

PubMed1993

A scanning electron microscopic study of the oviduct of the toad, before and during ovulation.

The surface features of the oviduct of the toad, Bufo melanostictus, was studied under the scanning electron microscope. The epithelial folds show regional variations, being longitudinally disposed in the upper part of the oviduct, spirally arranged in the middle and convoluted in the lower part. There is an abundance of cilia through the oviduct except in the ovisac. Goblet cells are interspersed among the epithelial cells. In between the epithelial folds are openings of tubular secretory glands. During ovulation, there is patchy loss of cilia throughout the oviduct. Most of the goblet cells are empty. On the surface, the cilia are matted together by secretory material which are laid down in layers.

Animals↗

PubMed1988

Scanning electron microscope and intragingival microorganisms in periodontal diseases.

During the past two decades there has been an increased understanding of bacterial invasion as a pathogenic mechanism of periodontal diseases. Scanning Electron Microscope (SEM) has played a key role in supporting the idea that bacterial invasion may be another pathogenic mechanism in periodontal disease. This has been due to the fact that SEM has a larger depth of focus and better resolving power than the Light Microscope (LM) and also allows for observation of rather large areas of tissue showing in depth the surface of the sample. This review deals with information obtained by using SEM as the fundamental method in studying and specifically identifying microorganisms within gingival tissues. New methodology using correlative microscopy for rapidly identifying invasive bacteria of periodontal tissues is discussed.

Bacteria↗

PubMed2001

Scanning electron microscopic observation of the architecture of collagen fibres in chicken M. iliotibialis lateralis.

1. The collagen architecture of M. iliotibialis lateralis in chicken was observed under the scanning electron microscope after muscle maceration in NaOH. 2. Immunohistochemical methods showed Type I and III collagens to be distributed over both perimysium and endomysium. 3. Thick perimysium around secondary myofibre fasciculi was composed of many large longitudinal collagen bundles and a few small circumferential bundles. In contrast, thin perimysium around primary myofibre fasciculi showed mainly circumferential bundles. 4. Endomysium had a honeycomb-like structure and consisted of a fine collagen mesh, its main fibre striation being circumferential. 5. It is suggested that functional demand differs between thick perimysium and thin endomysium.

Animals↗

PubMed1989

Action of a bacterial Achromobacter collagenase on the soft carious dentine: an in vitro study with the scanning electron microscope.

Samples of carious human teeth treated in vitro for 48-92 hours with a bacterial Achromobacter collagenase in solution in borate buffer at 33 degrees were examined with the scanning electron microscope. The enzyme was seen to destroy soft carious dentine but not sound layers of dentine beneath the lesion. This finding may have clinical implications.

Adult↗

PubMed1978

[Comparative studies with scanning electron microscope on the quality of corneal disk incision using various corneal trephine (author's transl)].

The cut surface of corneal stroma from rabbits was studied with a scanning-electron microscope and compared after using a manual trephine, a motor-driven rotor trephine and a rotor trephine with mechanical guidance. It became evident that the cut surface obtained with the motor-driven trephine is clearly smoother than that obtained with manual trephine. A further improvement in the quality of the cut is evident with a mechanically guided trephine.

Animals↗

PubMed1989

Scanning electron microscopic study of prepared cavities involving enamel, dentin, and cementum.

The dental treatment needs of many elderly people involve root surface caries and class V restorations. A scanning electron microscopic examination of extracted teeth with class V cavity preparations showed that well-developed cementum margins could be produced. Most studies regard the dentinocemental junction as behaving as dentin in relation to the restorative sealing process and possible marginal leakage. This study emphasizes the importance of the inclusion of cementum in class V cavity preparation and the possibility of marginal leakage occurring, depending on the restorative material used and whether acid-etch techniques are involved. Further studies on the cementum margin should be undertaken in regard to special treatment requirements related to bonding, marginal preparation, and marginal leakage.

Acid Etching, Dental↗

PubMed1978

Techniques for microdrop analysis of fluids (sweat, saliva, urine) with an energy-dispersive X-ray spectrometer on a scanning electron microscope.

Volumes of 10(-10) liter of sweat, saliva, and urine were analyzed with an energy-dispersive spectrometer (EDS) X-ray analyzer on a standard scanning electron microscope (SEM). Results of the EDS analysis of diluted and undiluted samples were verified by comparison with results of analyses of the same sample prepared by conventional quantitative methods. Except for Cl in concentrated urines and Mg in low concentrations, good agreement was found between the methods. The analysis provides quantitation of most elements of biological interest present in concentrations of about 1 mM, while it demonstrates good linearity (r greater than 0.99) throughout a wide range of commonly encountered biological concentrations. Reproducibility of the analysis is on the order of 2% and the minimal determinable concentration is generally between 0.5 and 1.0 mM for S, P, K, and Ca and slightly more than 1.0 mM for Mg.

Body Fluids↗

PubMed1987

Scanning electron microscope observations of hoof horn from horses with brittle feet.

Two types of defect were observed when hoof clippings from horses with brittle feet were viewed in the scanning electron microscope. The first defect showed a loss of structure and horn in the stratum externum. This defect was remedied after biotin treatment. The second defect showed poor attachment of the horn squames and failed to respond to biotin treatment alone. An improvement in this case was achieved by the addition of powdered limestone to the diet.

Animals↗