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Summary Chick duodenal mucosa contains an endogenous factor which is capable to inhibit selectively a homologous polyamine-sensitive protein kinase. The inhibitor was partially purified and characterized, and it was found to contain typical mucopolysaccharidic components.Glycosidases digestion studies, selective degradation analysis and spectrophotometric titrations with metachromatic dyes indicated that the inhibitor preparation contained two major moieties identified as heparin-like and heparan sulfate-like structures. In chick intestine the inhibitor was specific for polyamine-sensitive protein kinase since selectively interacted with it and was inert towards other cAMP-independent and cAMP-dependent protein kinases. The inhibitory effect of the endogenous factor was counteracted by naturally occurring polyamines such as spermine. The order of potency of various polyamines was: spermine > thermine spermidine diamines. The release of inhibition by addition of physiological concentrations of spermine was also apparent when using cytosolic proteins as endogenous phosphate acceptors. These results suggest that a possible role of polyamine in the regulation of polyamine-sensitive protein kinase in the intestine is to protect the enzyme from the inhibitory action of endogenous heparinoids.  相似文献   
2.
Histochemical and ultrastructural studies were made on the metacercarial cyst of Echinostoma revolutum obtained from the kidney of experimentally infected Physa and Lymnaea snails. Ultrastructural studies revealed three cyst walls, an outer, middle and inner. The outer wall was more electron-dense than the middle, and contained coarser granules than those found in the middle layer. The inner wall was lamellated and contained membranous whorls. Collagenous fibers presumably of host origin surrounded the outer cyst wall. The outer and middle cyst walls stained identically with all histochemical procedures used. These walls contained acid mucopolysaccharides and glycoprotein, whereas the inner cyst wall contained glycoprotein. All cyst walls stained positively with a variety of protein stains.  相似文献   
3.
This report summarizes major changes in previously published protocols for DNA extraction to improve the quality of DNA extracted from plants. Here, we highlight the critical modifications in the original protocols. The efficiency of these changes results in high-quality DNA ready to use in a variety of phytogenetically distant plant families, in particular species with mucopolysaccharides. The DNA obtained can be used without further purification in various molecular biology assays, including direct sequencing and AFLP and RAPD (random-amplified polymorphic DNA) analyses. The effectiveness of this method is proven by the amplification and sequencing of PCR products of up to 1 kb with DNA extracted from herbarium tissue ≥60 years old. This versatility is not usually found in DNA extraction protocols. In addition, this method is quick, adaptable to standard laboratories, and most important, safer and more cost-effective.  相似文献   
4.
Hartmannella culbertsoni trophozoites are transformed into viable cysts on exposure to a non-nutrient agar medium containing 15 mM MgCl2 and 20 mM taurine. Amebae differentiating in this encystment medium incorporate more uracil-2-14C into RNA and more leucine-1-14C or valine-1-14C into proteins than controls. Encysting organisms incorporate significantly more glucose-U-14C into cellulose and glucosamine-1-14C into mucopolysaccharides. Incorporation of glucose-U-14C into cellulose and of glucosamine-1-14C into mucopolysaccharides are inhibited by actinomycin D or cycloheximide.  相似文献   
5.
Collagen is one of the most common fibers in the extracellular matrix, where sulfated mucopolysaccharides are also located. In addition, sulfated mucopolysaccharides are present in some globet cells and secretory glands. The objective of this article is to develop a new staining method that detects these two macromolecules simultaneously in the same sample. The method described stains tissues in five fundamental colors: collagen in red; sulfated mucopolysaccharides in violet; red blood cells in yellow; muscle in orange; and nuclei in green.As a conclusion, it will be interesting in the future to evaluate whether this method could be used as a basic histological method, as a histology teaching tool, or even in histopathological and cytopathological studies.  相似文献   
6.
1986. Structure and composition of the metacercarial cyst wall of Sphaeridiotrema globulus (Trematoda). International Journal for Parasitology 16: 647–653. Histochemical and structural observations were made on the metacercarial cyst wall of Sphaeridiotrema globulus, obtained from naturally infected Goniobasis virginica (Pleuroceridae) snails. The cyst wall of S. globulus is a thin, glistening, transparent structure that thickens as the metacercaria ages. The cysts occur singly beneath the shell of the snail host or linked together in sheets, pyramids and other three dimensional forms. Light and electron microscopic examination of the cyst wall reveals an inner, middle and outer layer, each of which may vary in thickness. Adjacent cysts are linked by their outer layers. The chemical composition of these layers, elucidated through histochemistry, is described.  相似文献   
7.
The paper provides further clues as to the physiological function and biological significance of the ‘accessory gland’ in the metathoracic scent apparatus of the lygaeid Oncopeltus fasciatus. From various lines of evidence (gas chromatographic, cytochemical) it is concluded as probable that the accessory gland secretes small quantities of a mucopolysaccharide secretory product together with water. The difficulty of reconciling these data with other data indicating that the accessory gland is involved in the biosynthesis of the scent aldehydes is discussed. It is suggested that the water secreted into the median scent reservoir by the accessory gland provides O. fasciatus with a means of volumetric compensation for a diminished output of scent repellent.  相似文献   
8.
Taenia taeniaeformis infection course in C3H/He and BALB/c mice (susceptible and resistant respectively to T. taeniaeformis) was compared for 10 days post-infection (p.i.). Light microscopic observation of early organisms in BALB/c revealed host cell infiltration as early as 2 days p.i. By day 4 p.i. the larvae presented an inconspicuous acellular halo and were surrounded by a dense mass of leukocytes, mainly eosinophils. The amorphous substance reacted positive for sulphated acid mucopolysaccharides. By day 6 p.i. the parasite-host interface was filled by leukocytes and fibroblasts, staining with alcian blue was limited to small areas and the parasites appeared disrupted and lightly stained by haematoxylin-eosin. At day 10 p.i. the parasite had been destroyed by the host. In rats and C3H/He mice, the parasites at day 2 p.i. were 10 μm in diameter, bounded by a larger amorphous acellular halo that reacted positive to alcian blue stain, an indication of the presence of acidic muco-polysaccharides. By day 4 p.i. the clear halo became larger and reacted strongly positive for acid mucopolysaccharides particularly close to the organism. By day 6 p.i. alcian blue positive material appeared more diffuse, covering a broad area well inside the host tissue. By this time a layer of inflammatory cells were often present at some distance from the parasite tegument. By day 10 p.i. the larvae continued growing and increasing the number of tegumental cells. The presence of sulfated acid mucopoly-saccharides around the larvae probably serves as a protective barrier for the parasite by triggering the alternative pathway of complement, consuming C3 and C5, thus preventing cell attachment and humoral antibody attack. The early destruction of the parasite by cell defense mechanism implies a major role of cellular immunity in T. taeniaeformis elimination.  相似文献   
9.
Strongyloides ratti and Trichinella spiralis: net charge of epicuticle   总被引:1,自引:0,他引:1  
The intact epicuticles of Strongyloides ratti stage-3 larvae and Trichinella spiralis stage-1 larvae were found to have a surface net negative charge. Ultrastructural studies on S. ratti using cationized ferritin and ruthenium red showed the negative charge to be dense and uniformly distributed over the epicuticular surface. Staining with acetic acid-ferric oxide hydrosol occurred at pH 1.65 and suggests that amino acid carboxyl groups were not responsible for the negative charge property. Alcian blue staining occurred at pH 0.5 and at a critical electrolyte concentration (CEC) of 0.9 M MgCl2, a property similar to that of highly sulfated mucopolysaccharides such as the proteoglycan keratan sulfate. In contrast, T. spiralis larvae failed to stain with alcian blue below pH 5.0 or at a CEC of 0.1 M, suggesting its negative charge is associated with dissociated amino acid carboxyl groups. Attempts to remove the negative charge-bearing components in the epicuticle of S. ratti by detergents, organic solvents, denaturing agents, proteases, uronidases, neuraminidases, and lipases were unsuccessful. The presence of elastin in the S. ratti larval outer cortical layer was indicated by its vulnerability to elastase and its reaction to aldehyde fuchsin-alcian blue stain. These results show that the epicuticle of S. ratti is not a typical cell membrane, although it appears to have ultrastructural similarities. It is suggested that the association of highly sulfated mucopolysaccharides with the epicuticular surface of free-living nematodes such as S. ratti L3 may reflect a greater need to protect against surface desiccation. It is also postulated that the highly negatively charged surface may have anticomplementary and anticoagulation effects.  相似文献   
10.
Cultured lymphoid cells of both homozygotes and heterozygotes for cystic fibrosis could be distinguished from those of normals by (1) growth pattern, gross clumping, and (2) a relative increase in dermatan sulfate, with a normal total mucopolysaccharide content. Lines derived from the genetic mucopolysaccharidoses also had these characteristics, but their total mucopolysaccharide content was markedly increased. These observations support the hypothesis that the cellular disturbance in cystic fibrosis resides in those cellular regions whose functions would be altered by mucopolysaccharide composition.This research was made possible through a grant from The National Foundation-March of Dimes and, in part, supported by The Cystic Fibrosis Children's Fund and The National Cystic Fibrosis Research Foundation.Career Scientist of the Health Research Council of New York City (I-797).  相似文献   
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