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Antiserum to calbindin-D, a 28 KD vitamin D-dependent calcium binding protein, was used to localize the protein immunocytochemically in developing chick thyroid by both light and electron microscopy. The protein first appeared in future follicular cells of developing thyroid tissue from 8-day-old embryos. The number of calbindin-D-containing cells increased rapidly to a near-plateau level at day 10; this concentration was sustained until day 15, and then declined to an undetectable level just before hatching. The protein was distributed throughout organelle-free areas of the follicular cell cytoplasm and extended into the nucleus; it was not present in the follicular colloid. Comparison of the time course of changes in calbindin-D content with known differentiative changes taking place in follicular cells suggests that the protein may function in some yet to be determined mechanism related to normal development of the thyroid. 相似文献
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Z Mónus E Konyár L Szabó 《Virchows Archiv. B, Cell pathology including molecular pathology》1977,26(2):159-173
Morphologic and histochemical studies have been performed at light and electron microscopic level on needle-liver biopsy specimens, circulating blood lymphocytes and fibroblast cultures from patients with mannosidosis. The findings demonstrated generalized storage phenomena of varying degrees in the various tissues examined. Histochemical findings were in agreement with the biochemical nature of the stored material. Enzyme histochemical methods indicated storage in the lysosomes, at least in the hepatocytes. The ultrastructural appearance of mannosidosis in itself has but a limited diagnostic significance since the morphology and distribution of vacuoles have characteristics in common with other storage diseases. Repeated liver biopsy disclosed extensive storage in the hepatic tissue. However, the progression of the disease was not accompanied by severe mechanical destruction or microcirculatory disturbances. 相似文献
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W Domagala L G Koss 《Virchows Archiv. B, Cell pathology including molecular pathology》1979,30(2):231-243
Surface configuration of mesothelial cells identified by light microscopy (LM) has been studied by scanning electron microscopy (SEM). It has been shown that mesothelial cells may have a variable SEM appearance. The surfaces of a small proportion of mesothelial cells are covered by regular microvilli (MV) and show openings of the pinocytotic vesicles. The surfaces of the majority of these cells are covered by vesicles or blebs. An intermediate population of mesothelial cells, i.e., cells displaying side-by-side blebs and MV, has also been observed. The latter cells no longer display pinocytotic vesicles. Occasional mesothelial cells have smooth surfaces. It has been shown by LM and transmission electron microscopy that cells with blebs are viable and capable of mitotic activity. It is concluded that mesothelial cells, detached from their epithelial setting, lose microvilli and pinocytotic vesicles and acquire surface blebs. The possible relationship between mesothelial cells and macrophages based on surface features has been discussed. 相似文献
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Collagenous network in cartilage of human femoral condyles. A light microscopic and scanning electron microscopic study 总被引:1,自引:0,他引:1
To determine the spatial arrangement of collagen fibrils in articular cartilage of the human femoral head, three healthy femoral heads, obtained at necropsy, were examined by light microscopy and scanning electron microscopy. Light microscopic observations revealed no collagen fibril organization. Scanning electron microscopic observations showed a fine fibrillar texture throughout the articular cartilage. At the articular surface, smooth and fibrillated areas were detectable. Underneath the articular surface, the collagen network in the superficial zone showed a tighter appearance when compared with the homogeneous collagen network of the matrix in the deeper zones. The calcified cartilage zone was well demarcated from the uncalcified cartilage. The arcade model of Benninghoff [Z. Zellforsch. Mikrosk. Anat. 2: 783-862 (1925)] could not be confirmed. It was concluded that the organization of collagen fibrils in hyaline cartilage shows a three-dimensional network of randomly oriented fibrils. 相似文献
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The innervation of the posterior ligamentous structures of the human lumbar spine was studied by light microscopy, scanning electron microscopy and transmission electron microscopy. Three types of nerve endings were recognized: free nerve endings, Paciniform corpuscles and Ruffini corpuscles. The free nerve endings, which are thought to act as nociceptors, were found in the superficial layers of all ligaments. A few free nerve endings were also identified within the supraspinous and interspinous ligaments. The Paciniform corpuscles were predominantly found in the supraspinous ligament. The Ruffini corpuscles were located in the interspinous and flaval ligaments. These findings suggest that the posterior ligamentous structures could be involved in the spinal control system. 相似文献
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Lectin-binding pattern in normal human gastric mucosa. A light and electron microscopic study 总被引:1,自引:0,他引:1
Normal human gastric mucosal cells were examined by light and electron microscopy using lectins as a probe. The ABC method was used with biotinylated lectins for light microscopy and HRP-labeled lectins for electron microscopy. The human gastric mucosal cells revealed specific binding patterns for each lectin by light microscopy. Among the lectins tested, in particular, DBA gave a characteristic pattern. It specifically stained the supranuclear region of surface epithelial cells and the perinuclear region of parietal cells. By electron microscopy, the stacked cisternae and the vesicles of the Golgi apparatus of the surface epithelial cells were positive for the DBA staining. These results show that the DBA-positive supranuclear region observed by light microscopy corresponds to the Golgi apparatus. In the parietal cells, DBA, RCA and ConA bound to the intracellular secretory canaliculi which are invaginations of the cell membrane running around the nucleus in the cytoplasm. Therefore, the tubular perinuclear positive region observed by light microscopy corresponds to the membranes of the intracellular secretory canaliculi. In addition, the ConA reagent stained the endoplasmic reticulum, Golgi apparatus, nuclear envelope, and cell membrane of the parietal cell, which explains the diffuse cytoplasmic staining observed at the light microscopic level with this lectin. Lectins have proved to be very useful for the evaluation of in situ cytochemical aspects of the glycoconjugates characteristic to human gastric mucosal cells. 相似文献
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Charles W. Mims 《Protoplasma》1973,77(1):35-54
Summary The conversion of the plasmodium ofS. virginiensis into sporophores has been examined at both the light and electron microscopic levels. Particular attention has been paid to stalk and columella formation, capillitial formation, nuclear behavior during sporulation and spore formation. Both the stalk and columella are formed within the sporangial initial as intraprotoplasmic secretions. A portion of the capillitium arises directly from the columella while the remainder forms within an anastomosing system of tubular vacuoles. As spore cleavage begins the nuclei within the sporangium begin to divide mitotically. The protoplasmic content of the sporangium is first divided into small protospores which typically contain a single dividing nucleus. Following the completion of mitosis each of these segments cleaves into yet smaller segments which develop into spores. Meiosis occurs in the spores some 12–16 hours after cleavage. 相似文献
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Synopsis The presence of cholinesterase activity in association with capillaries of the central nervous system was investigated in the rat by means of both light and electron microscopic methods. Throughout most of the rat brain, the smaller blood vessels stain intensely for butyrylcholinesterase activity. In some areas, such as the commissural nucleus of the vagus and parts of the medial thalamus, the capillaries possess both acetylcholinesterase and butyrylcholinesterase activity. Blood vessels in those structures which lie outside the blood-brain barrier are completely devoid of cholinesterase activity. The electron microscope reveals that reaction product occurs within the matrix of the basement membrane, in the intermembranous space of the endothelial nuclear envelope and occasionally in the endothelial granular endoplasmic reticulum. It is suggested that the presence of cholinesterase within the basement membrane of brain capillaries is evidence of the role that the basement membrane may play in transfer mechanisms. 相似文献
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S. Kirkeby 《The Histochemical journal》1976,8(1):25-34
Synopsis The location of cholinesterase and non-specific esterase in the thyroid gland of the guinea-pig was studied with the light microscope. It was found that the inxodyl method for non-specific esterase activity under special conditions is superior to the cholinesterase method in a number of respects for the demonstration of the intra-, inter-and parafollicular cells. When using the indoxyl method the incubation period can be reduced from 2.5–3 hr to 40–50 min. Further, the reaction can be followed during the incubation. False localization of the reaction products is avoided, and nerves and erythrocytes are not stained.By varying the fixation time and the time of storage in gum arabic-sucrose, it was found that the miscellaneous activity of non-specific esterase in APUD cells (C-cells) and follicle cells may be due to both factors. In fresh tissue the activity of the enzyme was equal in follicle and C cells.Special cyst-like structures containing an esterase which is NaF-resistant whenn-naphthyl acetate is employed as a substrate and which gives a strong reaction at low pH values when 5-bromo indoxyl acetate is the substrate, are described, and their nature and possible origin are discussed. 相似文献
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The development of the crayfish retina was examined in embryos and first, second and third instars with both and light and electron microscope. Light microscopic observations indicate that differentiation begins at the posterior portion of the optic disc and progresses in an anterior direction. Development of screening pigment, dioptric elements, and rhabdoms all parallel this posterior to anterior gradient in the retina. Tracer studies in early embryos reveal that the retina is separated from the proximal neuropil regions by a distinct vascular space. This observation suggests that the source of new cells for the retina may not be the more proximal cell proliferation zone as previously indicated. It is proposed that mitotic activity within the retina and/or differentiation of cells from the anterior surface layer of the eye may be sources for addition of new cells to the retina. Proto-ommatidial clusters of seven retinula cells occur very early at the posterior region of the embryonic retina. Initially the receptor cells extend throughout the entire thickness of the retina, but later they withdraw from beneath the cornea to occupy only the proximal portion of the retina. Microvilli of the rhabdom arise from the centrally opposed membranes of the retinula cells in each cell cluster. Each new microvillus contains a core of fine filaments which extend out into the cytoplasm at its base. As development of the microvilli continues, the core filaments appear to be lost or altered, but the cytoplasmic bundles at the base of the microvilli persist. 相似文献
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Michael Melkonian Geoffrey Ian McFadden Ingo Botho Reize Hans Rudolf Preisig 《Plant Systematics and Evolution》1987,158(1):47-61
The green flagellateSpermatozopsis exsultans
Korshikov has been studied in culture by light and electron microscopy. The organism is naked, bears four flagella and is conspicuously spirally twisted. The ultrastructure and location of cell organelles (except the flagellar apparatus) has been investigated in detail using an absolute configuration analysis. With the exception of a doubling of the flagella and of the secondary cytoskeletal microtubule system,S. exsultans has the exact same complement of organelles occupying the same relative positions as has been described forS. similis. The two species are therefore correctly placed in the same genus. The usefulness of absolute orientations of cell organelles for green algal taxonomy and phylogeny is stressed.Dedicated to Prof.M. Mix on the occasion of her 60th birthday. 相似文献
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Corpora lutea were obtained surgically from fifteen mature Angus crossbred cows representing three experimental groups of five cows each. Cows in Group A were 180 days of gestation, cows in Group B had recently experienced parturition (=24 hours) and cows in Group C had recently exhibited standing estrus (=24 hours). Samples of corpora lutea were fixed in 10% buffered formalin and prepared for light microscopy and 2.5% glutaraldehyde and processed for electron microscopy. Luteal cells from cows in Group A were of two distinct types, large cell and small cell types. The large luteal cells of both Groups A and B were similar, with one exception. Those from cows in Group B stained less intensely and the nuclear chromatin appeared less pronounced and marginated. Small luteal cells were not readily observed in corpora lutea from Group B. In addition, there was evidence of pyknosis, karyorrhexis and mononuclear cell infiltration in corpora lutea from Group B. Luteal cells from cows in Group C were characterized by atrophy of the nucleus and vacuolation of the cytoplasm. Vascular changes consisted of endothelial cell necrosis and pyknosis of cells of the tunica media of arteries within the corpus luteum. Ultrastructurally, there were distinct differences in all groups with respect to the size and quantity of lipid droplets, the presence of electron lucent vesicles in the cytoplasm and indentations of the nuclear membrane of luteal cells. The results of this study suggest that at the time of parturition in the cow luteolysis may involve primarily small luteal cells, and that the corpus luteum may be a source of progesterone, which is likely a function of the large luteal cells. 相似文献
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J Stingl S Vozehová M Kriska V Kovalcík 《Zeitschrift für mikroskopisch-anatomische Forschung》1976,90(2):209-218
The development of changes appearing with the closure of ductus arteriosus was followed in mature rabbit foetuses with the help of light and electron microscopy. In the foetuses, in which there was no spontaneous respiration of atmospheric air before fixation the ductus remained opened. In smooth muscle cells of the media there were enlarged cisternae of the endoplasmic reticulum being partially decayed. The foetuses that respired for about one minute had the ductus contracted to various degree and the endothelial cells were expelled into the lumen. In the foetuses respiring for 10 minutes the ductus were more contracted. The endothelium was considerably waved and the agglomeration of smooth muscle cells appeared. In the endothelial and musclar cells the endoplasmic reticulum was richer, and in a lot of places considerably disturbed. The ductus of foetuses respiring for 15 minutes had the lumen completely closed. The smooth muscle cells had a significantly changed their internal structure. The possibility of the direct transformation of the endoplasmic reticulum of the smooth muscular cells into inclusion bodies during the ductus arteriosus closure is discussed. 相似文献
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