The environment of axonal migration in the developing chick retina: A scanning electron microscopic (SEM) study

1979 ◽  
Vol 184 (3) ◽  
pp. 519-535 ◽  
Author(s):  
Angela Suburo ◽  
Nestor Carri ◽  
Ruben Adler
Keyword(s):  
Electron Microscopic ◽  
Chick Retina ◽  
Sem Study ◽  
Scanning Electron Microscopic ◽  
Scanning Electron

Craniofacial abnormalities induced by retinoic acid: a preliminary histological and scanning electron microscopic (SEM) study

2000 ◽  
Vol 52 (5) ◽  
pp. 445-453 ◽  
Author(s):  
E.-N. Emmanouil-Nikoloussp ◽  
M. Goret-Nicaise ◽  
Ch. Foroglou ◽  
E. Katsarma ◽  
A. Dhem ◽  
...  
Keyword(s):  
Retinoic Acid ◽  
Craniofacial Abnormalities ◽  
Electron Microscopic ◽  
Sem Study ◽  
Scanning Electron Microscopic ◽  
Scanning Electron

Scanning Electron Microscopic Study of the Eggs of the Warthog Louse (Haematopinus Phacochoeri)

1997 ◽  
Vol 3 (S2) ◽  
pp. 113-114
Author(s):  
C. Baker ◽  
E.D. Green
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Environmental Changes ◽  
General Structure ◽  
Electron Microscopic ◽  
Razor Blade ◽  
Scanning Electron Microscopic Study ◽  
Sem Study ◽  
Scanning Electron Microscopic ◽  
Scanning Electron

The large eggs of Haematopinus phacochoeri are found attached to the long dorsal mane bristles of the diurnal warthog. The eggs are generally exposed to great environmental stresses such as excessive sunlight and temperature as well as the occasional plunge under water or mud during grooming. This investigation was therefore undertaken to determine how the eggs of H. phococoeri are adapted to tolerate the various environmental changes it is constantly exposed to. To our knowledge no other SEM study on the eggs of this species has been performed.Specimens still attached to the bristles were fixed in 70% ethanol, dehydrated and ultrasonically cleaned. Some eggs were longitudinally sectioned with a razor blade to expose the chorionic layers. The eggs were critical point dried in liquid CO2, mounted and viewed by means of a Leica Stereoscan 420 scanning electron microscope.The general structure of the shell consists of two layers of chorion, i.e. the endo-and exochorion. These two layers are attached at the pre-formed line of weakness at the operculum and again near the hydropyle. Elsewhere these two layers are completely separated by the respiratory layer.

scholarly journals Experimental scanning electron microscopic investigation of pathological dentinogenesis in posteruptive tooth phase

2006 ◽  
Vol 53 (2) ◽  
pp. 95-103
Author(s):  
Jovan Vojinovic ◽  
Radoje Stevanovic ◽  
Slobodanka Hrvacanin
Keyword(s):  
Microscopic Investigation ◽  
Electron Microscopic Investigation ◽  
The Other ◽  
Electron Microscopic ◽  
Normal Expression ◽  
Sem Study ◽  
Complex Therapy ◽  
Scanning Electron Microscopic ◽  
Undifferentiated Cells ◽  
Scanning Electron

In the article are presented results of SEM study of pathological dentinogenesis on the human and dogs tooth in the different formative stages. The pathological dentinogenesis take place in the genetically predetermined way no matter of type of an irritation. The structure of pathological dentin depends upon the level of irritation and its duration. Lower level irritation produce the secretion of tubular dentine with irregular tubular direction, higher irritation stronger irregularities. Strong irritations damage odonoblastes, and they are replaced by undifferentiated cells. Lower level of differentiation produce more irregular dentine. New cells momentarily starts secretion, at the beginning the atubular dentine, and latter tubules arrear. The odontoblasts are very resistant cells, so even under of very strong irritants some of them could survive and continue formatting individual tubules detected within amorphous dentinal tissue. The resistance of odontoblasts is limited, specially when irritations are long enough exhausting formative potential of cells. Excreted dentinal tissue becomes more and more irregular. These biological facts should be consider in the therapy of puplodentinal complex. Therapy have to preserve conditions for undisturbed recovery of damaged odontoblasts, or new undifferentiated cells. In the other words biological principles insist on the preservation of conditions for the normal expression of formative cells genetically tasks.

Scanning Electron Microscopic Surface Study of Adhesive organ of Garra gotyla gotyla (Gray)

2017 ◽  
Vol 6 (5) ◽  
pp. 178-185
Author(s):  
M. S. Sharma ◽  
K. C. Sharma
Keyword(s):  
Epithelial Cells ◽  
Electron Microscopic ◽  
Lower Lip ◽  
Surface Ultrastructure ◽  
Adhesive Organ ◽  
Sem Study ◽  
Scanning Electron Microscopic ◽  
Conspecific Recognition ◽  
Scanning Electron ◽  
Microscopic Surface

An attempt to study the adhesive organ of Garra gotyla gotyla inhabiting hill streams of Aravalli region has been made using scanning electron micro-scope. The results were compared with that of scanning electron microscop-ic studies of the adhesive organ of G. gotyla gotyla of the Himalayan region. The SEM study reveals that the upper fringed lip (UFL)and the lower lip or the posterior free labial fold (PFLF) bears short stub shaped tubercles (ST). These tubercles in turn bear numerous spines (S). The tubercles are covered with squamous epithelium (SE) indicating that spines are modified squamous epithelial cells. The margins of stub-shaped tubercles bear smaller spines; their size increases from margin to the centre. The surface ultrastructure of the adhesive disc of G. gotyla gotyla revealed the presence of hexagonal epithelial cells with elevated cell boundaries. Each spine is attached to callous pad with a broad base. The spines are used for anchorage to the substratum so that fish can scrap food even in fast current of water. Tubercles are used by fish for protection against mechanical injuries. Further these may be taxo-nomically used for conspecific recognition. Cumulative action of tubercles and mucus enables the fish to make firm hold on the substratum.

Primary atrophic rhinitis: a scanning electron microscopic (SEM) study

1980 ◽  
Vol 94 (9) ◽  
pp. 985-992 ◽  
Author(s):  
R. F. E. Gray ◽  
R. P. E. Barton ◽  
J. L. W. Wright ◽  
P. N. Dilly ◽  
R. F. Moss
Keyword(s):  
Atrophic Rhinitis ◽  
Electron Microscopic ◽  
Sem Study ◽  
Scanning Electron Microscopic ◽  
Scanning Electron

scholarly journals Somatic Embryos in Catharanthus roseus: A Scanning Electron Microscopic Study

2014 ◽  
Vol 6 (2) ◽  
pp. 167-172 ◽  
Author(s):  
Junaid ASLAM ◽  
Abdul MUJIB ◽  
Mahendra Prasad SHARMA
Keyword(s):  
Catharanthus Roseus ◽  
Somatic Embryos ◽  
Raw Materials ◽  
Early Stage ◽  
Electron Microscopic ◽  
Sem Study ◽  
Scanning Electron Microscopic ◽  
Metabolite Synthesis ◽  
Scanning Electron

Catharanthus roseus (L.) G. Don is an important medicinal plant as it contains several anti-cancerous compounds, like vinblastine and vincristine. Plant tissue culture technology (organogenesis and embryogenesis) has currently been used in fast mass propagating raw materials for secondary metabolite synthesis. In this present communication, scanning electron microscopic (SEM) study of somatic embryos was conducted and discussed. The embryogenic callus was first induced from hypocotyls of in vitro germinated seeds on which somatic embryos, differentiated in numbers, particularly on 2,4-D (1.0 mg/L) Murashige and Skoog (MS) was medium. To understand more about the regeneration method and in vitro formed embryos SEM was performed. The SEM study revealed normal somatic embryo origin and development from globular to heart-, torpedo- and then into cotyledonary-stage of embryos. At early stage, the embryos were clustered together in a callus mass and could not easily be detached from the parental tissue. The embryos were often long cylindrical structure with or without typical notch at the tip. Secondary embryos were also formed on primary embryo structure. The advanced cotyledonary embryos showed prominent roots and shoot axis, which germinated into plantlets. The morphology, structure and other details of somatic embryos at various stages were presented.

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