摘要:

SYNOPSISThe research was undertaken with two distinct ends in view: first, to discover what it is, in terms of fine structure, that histologists and cytologists are looking at when they examine routine sectioned material by light microscopy; secondly, to build a rational basis for the process of fixation in electron microscopy itself, by a detailed study of the effects of those fixative substances that are appropriate for this purpose. The whole of the work has been done with the exocrine pancreatic cell of the mouse as test material.

ISSN:0368-3974    

DOI:10.1111/j.1365-2818.1965.tb02114.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

摘要:

SYNOPSISA virus isolated from the pig and showing characteristics of an adenovirus has been examined by electron microscopy in both the purified state and in tissue culture cells. The virus is icosahedral in shape, has 252 capsomeres per capsid, and is characteristic of the adenovirus group. Examination of infected cells shows that the virus is predominantly intranuclear but virus has also been demonstrated in the cytoplasm. The cellular relationships characterise the adenovirus as more likely to be a member of the sub‐group containing types 3, 4 and 7 than that containing type 5. The virus is closely associated with the chromatin of the nucleus, in which parallel densely staining fibres have been demonstrated. Other structures with a rectilinear profile have been observed which have dense cores, evidence of a helical component and loci resembling the spheroidal form of virus.The first report of the isolation from a pig of a virus resembling an adenovirus was made by Haiget al. (1946): the results of serological tests indicated that the virus possessed the adenovirus group antigen but there was no neutralisation against several of the commoner human adenoviruses; the cytopathic changes in tissue culture were of the type described for the sub‐group of human adenoviruses types 3, 4 and 7. This paper records an electron‐microscope study of the morphology of the virus, the changes in infected tissue‐culture cells and the micro‐ecology of

ISSN:0368-3974    

DOI:10.1111/j.1365-2818.1965.tb02115.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

摘要:

SYNOPSISMorphological studies by electron and light microscopy have been made on the structure of the pig blastocyst at the 12 to 14 day gestation age. Trophoblastic and endodermal monolayers have been shown to contain cells with cytoplasmic filaments of about 80 to 90 Å across and several thousand Ångstroms long. There appeared to be a close association between the filaments and nuclear envelope as well as the desmosomes. The complex arrangement of the filaments is described and it is suggested that in embryonic cells they possess more than one function and relationship to the “bond fastening body” desm

ISSN:0368-3974    

DOI:10.1111/j.1365-2818.1965.tb02116.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

摘要:

SYNOPSISIn this histochemical study the patterns of activity and sites of localization of 5‐nucleotidase in a series of human pathological thyroid glands are reported. An association is demonstrated between seasonal changes of temperature and the level of enzyme activity; a relationship between this activity and involutionary change is also shown. The sites of localization of this enzyme suggest a role in cell transport mechanisms; this is discussed and related to the other observations. The significance of 5‐nucleotidase as a link in the overall control of thyroid function is conside

ISSN:0368-3974    

DOI:10.1111/j.1365-2818.1965.tb02117.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

摘要:

SYNOPSISThe object of this work was to determine the main ultrastructural features of the ommatidium with particular reference to its base and the region of the cone; to establish some architectural features of the first optic ganglion and to clarify the nature of the connections between the ommatidium and the periopticon. Studies of sections cut in several planes have led to the construction of an incomplete schema depicting the main pattern of connections. It is suggested that this pattern is similar in principle to some of the connections found between first and second neurone in the vertebrate retina.It is pointed out that the dimensions of the ommatidium are well suited to the task of providing maximum spatial resolving power together with high sensitivity.The prevalent view that individual rhabdomes in a particular ommatidium can be differentially stimulated is also shown to be highly unlikely. In addition, the finding that the constituent microtubules of radially opposed rhabdomes are parallel is not confirmed.Regularly sized and spaced densities on the plasma membranes of the rhabdome microtubules are reported and the possibility is raised that these may bear some relation to photo‐pigments.A new variety of synapse is reported on localized lengths of axon in the 1st optic ganglion.Finally, the belief that the compound eye is an image‐forming device is criticized and it is suggested that it is more concerned with data processing of light‐evoked responses in order to generate signals concerning particular aspects of the enviro

ISSN:0368-3974    

DOI:10.1111/j.1365-2818.1965.tb02118.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

摘要:

SYNOPSISThe electrophoretic analysis of aldehyde fuchsin solutions in 70 p.c. ethanol between pH 2·5 and 3·5 shows that the dye is basic, and that solutions of different ages have different components. Young solutions possess reddish violet and red components, the latter probably representing unused basic fuchsin which soon disappears. The oldest solutions possess bluish violet, reddish violet, and bluish green components, of which the latter is the most mobile. It is suggested that the colours of the components may represent the state of substitution of their constituent molecules, and that the mobilities of the components may be the result of polymerization.An experiment with precipitated dye showed that the bluish violet component of old dye was more soluble in acidified 70 p.c. ethanol than the reddish violet component of young dye. The bluish violet component at saturation was as good a stain as young reddish violet dye, whereas the old dye from which the bluish violet component was precipitated was a slow and weak dye. It is suggested that the ageing of aldehyde fuchsin may involve a change of solubility as a result of increase of molecular weight, and this may contribute to the poor staining of old solution

ISSN:0368-3974    

DOI:10.1111/j.1365-2818.1965.tb02119.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

摘要:

SYNOPSISThe indoxyl and naphthol AS techniques, used in association with Mipafox and E600, indicate the presence of both organophosphate‐sensitive and organophosphate‐resistant esterases in the rat ovary. Organophosphate‐sensitive type B enzymes occur in the theca interna and interstitial cells; a B‐esterase activity is particularly prominent in the corpus luteum of pregnancy. The organophosphate‐resistant type C enzymes are demonstrated in macrophages, interstitial cells, theca interna, germinal epithelium and granulosa cells of atretic follicles. In corpora lutea the C‐esterase activity increases with the ageing and degeneration of the luteal cells. The distribution of organophosphate‐resistant esterase is very similar to that of acid phosphatase and the high content of these lysosomal enzymes in the ovary may be an important factor in its responses to hor

ISSN:0368-3974    

DOI:10.1111/j.1365-2818.1965.tb02120.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

摘要:

SYNOPSISHistochemical and electron‐microscopical techniques have been employed to study fibrinoid material present in the mouse placenta. These show the material to be an amorphous substance of moderate electron‐density, which stains characteristically with the periodic acid‐Schiff and Hale colloidal iron reactions. Auxiliary techniques, including enzymic digestion, have enabled greater specificity to be obtained from these reactions, and show that the placental fibrinoid contains a mucoprotein rich in tryptophane, with at least two non‐sulphated acid mucopolysaccharides, probably hyaluronic and sialic acids.The fibrinoid is present around each trophoblast cell and as a layer between the foetal and maternal components of the placenta. Considerably more fibrinoid is evident in placentae from hybrid than from inbred matings.It is suggested that the fibrinoid material in the mouse placenta acts as a barrier to prevent the egress of foetal transplantation antigens into the

ISSN:0368-3974    

DOI:10.1111/j.1365-2818.1965.tb02121.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

摘要:

SYNOPSISThe presence of mucous glands at the lower end of the ureter of a donkey is reported. Tubular acini are also present in the musculature of the bladder trigone. These latter may represent aberrant mesonephric tubules or aberrant Home's glands.

ISSN:0368-3974    

DOI:10.1111/j.1365-2818.1965.tb02122.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

摘要:

During routine maceration of shales for the extraction of fossil spores, a number of unusual structures appeared which were eventually identified as osteocytes from scales belonging to a palaeoniscid, a primitive bony fish. No vertebrate tissues had been expected, since the technique employed destroys virtually all substances with the exception of carbon, chitin and cellulose. It thus appears that certain vertebrate tissues are far more resistant than was generally believed.The specimen comes from rocks of Upper Carboniferous age (Namurian, Arnsbergian Stage, zone E2b), which outcrops at Hollywood Dingle, near Endon, Staffordshire (Grid ref. SJ.945509), and the palaeoniscid was kindly identified by Mr. H. A. Toombs of the British Museum (Natural History) asElonichthys semi‐striatusTraquai

ISSN:0368-3974    

DOI:10.1111/j.1365-2818.1965.tb02123.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY