PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Microscopy, Electron”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 469 records · Page 26Linked to original sources
PubMed1987

[Effect of the soft laser on gingival connective tissue. II--Effect on wound healing. Optical microscopy, histoenzymology and electron microscopy studies].

The effect of soft-laser upon cicatrization of the gum was studied in 14 patients. After the initial biopsy, control biopsies were performed on the same patients in non-irradiated gums. In the absence of inflammation, cicatrization took place in a similar manner in the irradiated and control tissues. After an early vascular growth, connective cylinders occurred, accompanied by an increase of enzymatic activity) (oxidative enzymes, leucine aminopeptidase, alkaline phosphatase). Then, the scar was formed of longitudinal bundles. The laser induced an earlier cicatrization (14th day) than in the controls (21st day). The presence of inflammation in the gum delayed cicatrization and often promoted cheloid scars with abnormal anastomosing connective bundles. In this case also, irradiation by soft-laser was followed by a quicker and better cicatrization.

Fibroblasts↗
PubMed1982

A comparative study on application of Nd-YAG laser radiation and electrocautery in canine gastric mucosa--magnified observations by dissecting microscopy and scanning electron microscopy, and histological examinations.

The mucosal change, the depth of injury and the healing process in the canine gastric wall after Nd-YAG laser (YAG) exposure and electrocautery were studied comparatively by magnified observations. The results were as follows: 1. Mucosal changes caused by the YAG laser beam were more localized within the exposure area than those by electric current. 2. The depth of tissue damage to the canine gastric wall by YAG laser exposure was easy to control when compared to that caused by electrocautery. 3. The healing time of the ulcer caused by the YAG laser was shorter than that caused by high frequency current. 4. In the present study on the mucosal changes due to laser exposure and electrocautery using endoscopy, dissecting microscopy and SEM, it was found that these examinations appear to be helpful as experimental procedures to clarify the detailed appearance of the mucosal surface. It was suggested that endoscopic application of the YAG laser to the gastrointestinal tract was safe and effective when compared with other procedures which have been applied endoscopically for diagnosis and treatment.

Animals↗
PubMed2006

Characterization of acrylic polyamide plastic embolization particles in vitro and in human tissue sections by light microscopy, infrared microspectroscopy and scanning electron microscopy with energy dispersive X-ray analysis.

Vascular embolization is a well-established practice for the treatment of tumors and vascular lesions. Rounded beads (microspheres) of various materials (collagen, dextran and trisacryl-polymer-gelatin) were developed to solve problems encountered with earlier versions of embolic material. We performed histochemistry, Fourier transform infrared microspectroscopy and scanning electron microscopy with energy dispersive X-ray analysis on two uterine and one hepatic specimen with unidentified intravascular foreign material, and examined a reference embolization product for comparison. The hematoxylin and eosin stained tissue sections showed multiple foci with unidentified intravascular foreign material and fibrous obliteration of vessel lumens. Only one case had a clinical history of previous embolization but without specifying the material used. One case was submitted for identification of a 'parasite'. The material stained positively with Sirius red and mucicarmine, variably with Masson's trichrome stain and Movat pentachrome, and did not stain centrally with periodic acid Schiff with diastase. Infrared spectrophotometric analysis of the material from all three cases demonstrated the spectrum of acrylic polyamide plastic. A control sample of EmboGold exhibited infrared microspectroscopic spectra similar to the three tissue specimens. Analysis by scanning electron microscopy with energy dispersive X-ray analysis demonstrated some differences in elemental composition between the tissue sections and the selected reference material. To our knowledge, this is the first report of infrared spectrophotometric analysis with scanning electron microscopy with energy dispersive X-ray analysis of an acrylic polyamide plastic embolization product both in vitro and in human histologic tissue sections. In cases lacking appropriate clinical information, identification by these methods and/or a panel of special stains may assist pathologists unfamiliar with this material's light microscopic appearance.

Acrylic Resins↗
PubMed1988

Nail changes in alopecia areata: light and electron microscopy.

Fragments of nail keratin removed with tweezers from patients suffering from alopecia areata were examined using light microscopy and electron microscopy. The results obtained from these two techniques show nail changes which are slits, cupuliform dips of the upper edge and parakeratosis, under light microscopy; vacuoles, depletion of keratin fibers, and electron-dense fibrillary deposits, under electron microscopy. These changes predominate in the nail plate with a maximum in the upper part while the subungual keratin is preserved. A serious disorder of the matrix keratinization is probably the source of this preferential localization. To determine whether it is a disorder of the keratin fibers themselves or rather of the interfilamentary matrix and especially of the filaggrin system will require further biochemical and immunological studies.

Alopecia Areata↗
PubMed1986

Asbestos fibres in bronchoalveolar lavage fluid from asbestos workers: examination by electron microscopy.

The uncoated and coated fibre load in bronchoalveolar lavage (BAL) fluid was assessed using light microscopy, scanning electron microscopy, and x ray microanalysis in 15 subjects with previous, unprotected exposure to asbestos, including three with clinical and radiological evidence of asbestosis, and in 13 urban dwelling control subjects with no known occupational exposure to asbestos. The mean ferruginous body count per ml BAL fluid in asbestos exposed subjects as determined by light microscopy was 52 (range 0-333). No ferruginous bodies were detected in control subjects. The mean fibre count per ml BAL fluid in asbestos exposed subjects as determined by electron microscopy was 793 (133-3700), significantly greater than 239 (44-544) in controls (p less than 0.05). Electron microscopic counts correlated with duration of previous exposure to asbestos (r = 0.47, p less than 0.05) and with percentage neutrophil counts (r = 0.53, p less than 0.025). There was no relation between electron microscopic fibre counts and light microscopic ferruginous body counts. In 11 asbestos exposed cases x ray microanalysis confirmed the presence of asbestos and in six the asbestos fibre type was clearly identified. Of five subjects showing no asbestos bodies by light microscopy, all showed fibres by electron microscopy, and in three cases the presence of asbestos was confirmed by microanalysis. Among control subjects, fibres were either large organic fibres or smaller particles which microanalysis showed were not asbestos. In only one control case were a few fibres identified which were confirmed as asbestos fibres on microanalysis. Electron microscopic examination of BAL fluid may confirm past exposure to asbestos and probably gives a crude quantitative estimate of asbestos load.

Adult↗
PubMed1991

Use of electron microscopy in examination of faeces and rectal and jejunal biopsy specimens.

The stools and rectal biopsy specimens of 44 patients with AIDS and diarrhoea were examined by culture, light microscopy, and electron microscopy. In 13 patients examination of rectal biopsy material and faecal samples showed no pathogen, but in two of these, microsporidiosis was found by electron microscopical examination of jejunal biopsy specimens. This organism was also identified electron microscopically in one of the further five jejunal biopsy samples taken from patients with a known cause of diarrhoea. Blastocystis hominis infection was identified electron microscopically in six patients, all of whom had cryptosporidiosis additionally seen by light microscopy. Four of these six patients remained well for long periods, with only moderate diarrhoea, and follow up showed no evidence of blastocystis infection. In only four of 11 patients found to have cryptosporidium in their stools at light microscopy were organisms found at electron microscopy. Viral inclusions were only identified at electron microscopy in one of 10 patients with an opportunistic viral infection seen at light microscopy (cytomegalovirus n = 7, herpes simplex virus n = 3). No additional viral pathogens were detected in either stools or rectal biopsy material by electron microscopy. It is concluded that routine electron microscopic examination of stool samples or rectal biopsy material taken from patients with AIDS and diarrhoea is unnecessary and does not increase the yield of potential pathogens compared with standard microbiological techniques and histology.

Acquired Immunodeficiency Syndrome↗
PubMed1988

[Distribution of lymph vessels in the plica vocalis of the human. A light microscopy, enzyme histochemistry and electron microscopy study].

Results of studies on the presence of lymphatic capillaries in the plica vocalis are shown, using improved methods of preparation. Immediately after laryngectomy, followed by immediate fixation of the non-pathological plicae vocalis, large lymphatic capillaries can be easily identified in the specimen. Lymphatic capillaries, which cannot be seen in conventional light microscopy, are now histochemically demonstrated with a marker of 5' nucleotidase. These histochemical results are confirmed by electron microscopy. Using a combination of both methods, a different quantity of subepithelial lymphatic capillaries can be visualised over the whole length and width of the plica vocalis. Lymphatic capillaries below the stratified squamous epithelium in the region of the anterior commissure grow gradually more numerous up to the folds of the arytenoid cartilage. Hence, in contrast to previous studies, the superficial lymphatic capillary system of the laryngeal mucosae is not separated into a supraglottic and subglottic lymphatic net of the vocal cord.

5'-Nucleotidase↗
PubMed1991

Detection of B19 parvovirus in human fetal tissues by electron microscopy.

We present the electron microscopy observations on samples from 38 pregnancies that were investigated for B19 parvovirus infection. Thirty-four had resulted in fetal loss thought to be due to a virus infection and 22 of the 38 were positive for B19 parvovirus in one or more of the tissues. Twenty-one placentas and 75 fetal tissue samples were examined. Fresh samples were investigated by immune electron microscopy while formalin-fixed tissues were examined as thin sections and by negative staining of tissue extracts with direct electron microscopy. Electron microscopy was more sensitive on fresh than on fixed samples. The ultrastructural observations on thin sections of fixed tissues yielded new information locating B19 parvovirus particles in both nucleus and cytoplasm of infected fetal cells. The diagnostic results of the range of electron microscopy assays were compared with those of two hybridization methods. The fresh samples yielded comparable results from electron microscopy and hybridisation assays but on formalin-fixed materials hybridisation was more sensitive.

Erythema Infectiosum↗
PubMed1987

Scanning electron microscopy in the backscattered electron imaging (BEI) mode: applications to clinical hematology.

Elements of high atomic number backscatter electrons that carry information of cytochemical and of immunocytochemical significance in high resolution scanning electron microscopy (SEM). Reaction products of enzyme cytochemistry containing lead or osmium have been used to localize the sites of phosphatase and of endogenous peroxidase, respectively. Particles of colloidal gold, ranging in diameter from 40 to 13 nm, have been successfully used to label cell surface antigens specifically identified by murine monoclonal antibodies. The diagnostic potential of the scanning electron microscope in clinical hematology appears to be considerably enhanced by the use of the backscattered electron imaging (BEI) mode. Quantitation of the number of gold-labeled epitopes on cell surfaces cannot be achieved in the conventional secondary electron mode of the SEM, but is an attractive possibility in the backscattered electron imaging mode.

Antigens, Surface↗
PubMed1978

[Characterization of heavy metal secretory granules in the islet tissue of adult white rats by means of the light and electron microscopy, including the high voltage electron miscroscopy and the electron microanalysis (author's transl)].

The metal secretory granules of Langerhans' islets of white rats were examined after histochemical detection by sulfide silver staining method as well as by conventional electron microscopy and high voltage electron microscopy. Zinc and calcium were determined with electron probe x-ray-microanalysis. The metals are located at the inside of cytoplasmatic vacuoles, a result, we discuss in connection with the release of pancreatic hormones.

Animals↗