摘要:

Abstract.Epithelia from skin, palate, buccal mucosa and dorsal tongue were studied in normal and zinc deficient guinea pigs by transmission electron microscopy. Gap junctions (nexuses) were observed primarily in the basal and prickle cell layers. They were also seen to form bulging and looping configurations which appeared to pinch off into the cytoplasm forming what are recognized as annular gap junctions. These may be attached to the surface or represent separate, intracytoplasmic, nexus‐bound inclusions. Their contents varied, but most often they contained glycogen and ribosomal‐like particles. Various cell organelles were also seen entrapped, most common of which were membrane coating granules. The development of these annular gap junctions is a prominent feature of many epithelia. It has been suggested that they probably serve to maintain a synchronized differentiation throughout the various epithelial lay

ISSN:0904-2512    

DOI:10.1111/j.1600-0714.1979.tb01885.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

Abstract.Four canines of eight 2‐year‐old dogs were extracted surgically, a mucoperiosteal flap being raised. A standardized pair of the post‐extraction cavities were filled with three aspirin cones, the other pair being used as controls. The flaps were sutured with surgical gut. The dogs were killed at intervals of 2, 4, 6 and 8 weeks; bone blocks including the cavities were resected and decalcified for histologic examination; serial sections were stained with hematoxylin and eosin. Microscopic observation on 2 week samples showed an inflammatory response with granulation tissue in both experimental and control cavities with delayed bone apposition in cavities filled with aspirin cones. The 4, 6 and 8 week samples did not show any major difference between the experimental and control cavities. We observed a decrease in infiltrating of cells followed in both by a similarly increasing amount of fibrous tissue and bone remodeling. These results were due perhaps to the details of the experimental method as the suture allowed aspirin to stay in the cavities for only a short time (2‐3 days), as occurs in clinical p

ISSN:0904-2512    

DOI:10.1111/j.1600-0714.1979.tb01886.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

Abstract.Unaltered surface enamel of extracted human teeth was subjected to tests of resistance to dissolution in 10 mM acetic acid at pH 4.0 and 10 mM EDTA at pH 7.4 in a miniature continuous flow system. Fluoride in EDTA had no effect on enamel dissolution. Inclusion of 0.25, 0.50 and 5.0 mM NaF in the acid at pH 4.0 greatly increased the resistance of the enamel to dissolution. The 0.5 mM NaF in the acid almost instantly reduced enamel dissolution and the effect persisted through the 1 h experiments. These results suggested that the acid labile fluoride in plaque and tooth minerals may provide the primary beneficial effect of all types of enamel fluoridation.

ISSN:0904-2512    

DOI:10.1111/j.1600-0714.1979.tb01887.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

Abstract.Several papules on the floor of the mouth and the ventral surface of the tongue of a zinc‐deficient rabbit were studied by light and electron microscopy. These papules appeared to be consistent with focal epithelial hyperplasia of man and chimpanzee. There was a concurrence of cytoplasmic vacuolization with the appearance of viral particles within the nucleus. Intranuclear crystalline viral aggregates were frequently observed in the upper spinous cell

ISSN:0904-2512    

DOI:10.1111/j.1600-0714.1979.tb01888.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

Abstract.The caries inhibitory effect of optimally fluoridated drinking water is well documented. Communities are often exposed to naturally fluoridated water with F content exceeding the optimal level. The purpose of this study was to determine the relationship between enamel fluoride, degree of fluorosis (DEGF) and caries incidence (DMFT) in an endemic fluoride area.Eighty‐five 14‐ to 16‐year‐old children (37 males and 48 females) who were born and had been living continually in the town of Kenhardt in South Africa were selected for this study. The fluoride content of the common water supply is 3.2 ppm F. The DMFT and DEGF were determined clinically. Acid etch biopsies were carried out on both maxillary central incisors of each subject. Ca and F analysis were carried out and mass enamel expressed in μg and mass F in pg. Data transformations to logc, mass F (1nF), logcmass En (1nEn) and were made. The 1nF values were corrected to a standarized depth of 10 μm (208.6 μg enamel equivalent mass) by covariance analysis. Correlations between the parameters , 1nF and DEGF were calculated, adjusting for the sex of the individual.The correlations were as follows:A positive association among the three parameters was e

ISSN:0904-2512    

DOI:10.1111/j.1600-0714.1979.tb01889.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

Abstract.The minor salivary glands in the hard palate and the submandibular gland of the Rhesus monkey were subjected to a liquid nitrogen, direct‐spray, one‐cycle freeze. A 4‐min freeze in the temperature range of –40°C to –60°C was used. The extent of tissue destruction was determined at intervals up to 1 year. Clinically relevant findings resulted and form the basis for subsequent studies by this group of in

ISSN:0904-2512    

DOI:10.1111/j.1600-0714.1979.tb01890.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

Books reviewed in this Article:H. J. Conn's Biological Stains, 9th edn., ed. R. D. Lillie with assistance from E. H. Stotz&V. M. Emmel.Endodontics, 2nd edn., by E. NichollsDevelopment of the Basicranium, ed. James F. Bosma

ISSN:0904-2512    

DOI:10.1111/j.1600-0714.1979.tb01891.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY