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1.
Nancy Burton Wurster George Lust 《Biochimica et Biophysica Acta (BBA)/General Subjects》1984,800(1):52-58
The content and the biosynthesis of fibronectin was examined in disease-free articular cartilage and in articular cartilage from osteoarthritic canine joints. Fibronectin content was increased in extracts of cartilage from osteoarthritic joints. Incubation of cartilage in vitro with [3H]phenylalanine and subsequent isolation of [3H]fibronectin from a gelatin affinity column and characterization by SDS-polyacrylamide gel electrophoresis and by immunoprecipitation indicated that disease-free and osteoarthritic cartilage explants synthesized fibronectin. About 50% of the [3H]fibronectin was recovered in the incubation medium. The osteoarthritic cartilage synthesized and accumulated up to 5-fold more [3H]fibronectin than disease-free cartilage. 相似文献
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An epithermal neutron activation method is used to determine the concentration of mineral elements in human dental enamel.
A large number (252) of samples from ancient and modern origins are analyzed. The analytical results are mathematically processed
using a statistical multivariant method. This allows to differentiate deciduous from permanent teeth and decayed from sound
enamel. It is also possible to distinguish the teeth coming from two different necropoles. The origin and the localization
of determined elements in the mineralized part, or in the aqueous-organic part, of enamel is suggested. Their role, as witnessed
in the physiopathological phenomena of dental enamel, is discussed. 相似文献
5.
The size relationship between the crown area of the lower canines (Cs), third (P3s) and fourth premolars (P4s), and first
molars (M1s) in hominids is examined by means of the regression analysis. The lower P3 seem to be under the influence of those
factors that control both the size of the anterior and posterior teeth, and the P4:P3 size ratio is related to the relative
size of the anterior and posterior dentitions. So, the P4>P3 sequence is associated with the megadontia and hipermegadontia
of the posterior teeth, whereas the expansion of the anterior teeth produces the P3>P4 sequence. We consider the P4:P3 size
ratio as an excellent indicator of the taxonomic and philogenetic status of fossil hominids. 相似文献
6.
Occurrence of heavy metals,sodium, calcium,and potassium in human hair,teeth, and nails 总被引:1,自引:0,他引:1
Barbara Nowak 《Biological trace element research》1996,52(1):11-22
Heavy metals in biological samples: nails, teeth, and hair were examined during 1991–1993. Investigations of biological samples
(hairn=249 samples, teethn=145, nailsn=80 samples) were provided for inhabitants of selected towns in Beskid Śląski. The towns are small mountain towns in southern
Poland: Wista, Szczyrk, Istebna, Koniaków, and Jaworzynka. The analysis of ANOVA and MANOVA variances were used for biological
samples in the context of age, sex, and type of samples for 12 elements (Pb, Cd, Cr, Zn, Fe, Cu, Mn, Ni, Co, Ca, Na, and K).
The matrix correlation and cluster analysis were applied to explain the behavior of metals in human hair, teeth, and nails. 相似文献
7.
Katherine Coffing Craig Feibel Meave Leakey Alan Walker 《American journal of physical anthropology》1994,93(1):55-65
A piece of mandible and several isolated teeth are reported from fluviatile sediments older than 4 million years at East Lake Turkana. They most closely resemble hominids from Laetoli, Tanzania and Hadar, Ethiopia which have been assigned to Australopithecus afarensis. © 1994 Wiley-Liss, Inc. 相似文献
8.
J. H. Van Wyk 《Biotechnic & histochemistry》1993,68(5):290-301
Two fixation fluids, two fixation techniques and two embedding methods were investigated for their effects on the quality of sections of teeth for pulpal response to filling materials to improve evaluation of pulpal responses. Sections from 32 baboon teeth were prepared, half with experimental cavities and half without, using either 10% formaldehyde or 4% glutaraldehyde, longitudinal tooth splitting or removal of the tooth apex, and paraffin or K plast resin embedding; decalcification in a formic acid mixture was a constant throughout. Histometric analysis showed that paraffin embedding produced less shrinkage than the K Plast resin embedding although the difference was not statistically significant. Six parameters of separation at the pu1p:dentine interface were studied: embedding, fixative, presence or absence of a cavity, cutting technique and individual animal tooth type. Statistical investigation revealed that fixative, cutting technique, and fixative and cutting technique combined had significant influences on the separation artifact. Of the combinations tested the choice of embedding method depends on which of the two artifacts, shrinkage or separation, is more adverse in the opinion of the investigator. Four percent glutaraldehyde together with the longitudinal split technique of fixation. processed by either K Plast resin embedding or paraffin embedding produced satisfactory pulpal sections. 相似文献
9.
L. O. Greenfield 《Human Evolution》1993,8(3):187-204
A tooth at the border between two morphogenetic fields (mandibular canine and honing premolar) may become morphologically
similar to and/or functionally incorporated with the teeth of either field. In light of this, observations of the morphology
and occlusion of female anthropoid C1s from 58 extant species are presented to assess whether and to what extent they exhibit incisor-like form and function. Female
C1s in 74% of the taxa observed exhibit well developed incisor-like traits which may reflect field border phenomena. In another
9%, incisor traits are present but they are not examples of field border phenomena. Interspecies variation in female C1 morphology is related to behavior, function, natural selection and phyletic inertia. A selection model, derived from the
data, is used to explain C1 sexual dimorphism and the evolution of male and female human canines. The data's relevance to the field vs clone theory debate
is also discussed. 相似文献
10.
Dog-DAT: a direct agglutination test using stabilized, freeze-dried antigen for the serodiagnosis of canine visceral leishmaniasis 总被引:2,自引:0,他引:2
Linda Oskam Rob J. Slappendel Eef G.M. Beijer Nel C.M. Kroon Cor W. van Ingen Seray Özensoy Yusuf Özbel Wiepko J. Terpstra 《FEMS immunology and medical microbiology》1996,16(3-4):235-239
Abstract We have evaluated the use of an improved direct agglutination test (DAT) based on stable, freeze-dried antigen for the detection of anti- Leishmania antibodies in canine serum samples. With a cut-off value of 1:640, the sensitivity of the DAT was shown to be 100% and the specificity of the test was 98.8%. 相似文献