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751.
Objective:  The aim of this study was to determine frequency and distribution of dental caries in an early medieval Avar population from Central Europe, namely Vienna.
Methods:  The evaluation of caries was carried out in an anthropological sample consisting of the remains of 136 individuals and included 2215 permanent teeth. Age and sex estimations were based on dental development and on skeletal ageing methods. The presence of dental caries was determined according to clinical aspects using a dental probe.
Results:  The frequency of ante mortem tooth loss in the sample was 23.8%; the total caries frequency was calculated as 14.9%. The highest caries rate was recorded in the second mandibular molar (34.6%). The most affected tooth surface was found to be the root with 12.7%, followed by the approximal surface with 8.6%, but only 7.7% of the occlusal surfaces were affected by caries.
Conclusion:  This study revealed that Avars suffered from higher caries rates than most other medieval European populations, but experienced a similar dental caries distribution. Attrition of the occlusal surface resulting from a diet containing abrasive particles with accompanying posteruptive tooth movement is considered the major factor causing this premodern caries pattern.  相似文献   
752.
Thirteen polymorphic tri- and tetra-nucleotide microsatellites are reported for the spotted snow skink (Niveoscincus ocellatus) from Tasmania. Variation was assessed among 40 individuals collected from a single locality. Most loci had 12–19 alleles, although one had more than 20 alleles, while observed heterozygosities ranged between 0.25 and 0.93. Eleven loci were also polymorphic in the congeneric species N. metallicus (N = 16 collected from a single locality).  相似文献   
753.
754.
In conventional transmission electron microscopy (EM), thinly sectioned specimens embedded in epoxy resin are observed. However, because of a substantial level of electron density of epoxy resin, the possibility cannot be ruled out that bio-structures having electron density similar to that of epoxy resin are not clearly recognized and thus are neglected or misinterpreted in conventional EM. This was the reason to require for embedment-free EM. Embedment-free sections have already been made available reliably by transient embedding in polyethylene glycol (PEG) and subsequent de-embedding through immersion in water, and further by critical-point drying, and this embedment-free EM is thus termed PEG-EM. However, this PEG-EM has not been successful to attract reasonable attention from electron microscopists and instead been misunderstood as a non-reliable method. In this paper, the remarkably enhanced contrast and electron translucency of any observation targets in PEG-EM are clearly demonstrated by comparing with images in conventional EM of adipocytes and neural myelin as examples. These features of PEG-EM, together with faithful correspondence in EM images of any individual substructures between the two methods, confirm the reliability of PEG-EM. Furthermore, the much higher thickness of embedment-free sections together with these features makes the PEG-EM more advantageous than the conventional EM for three-dimensional appreciation of structural elements, which is made by stereo-viewing of sections or by EM tomography. Therefore, the PEG-EM is regarded as an important adjunct to the conventional EM for histological studies and wide application of this method may unravel a new level of histology.  相似文献   
755.
The objectives of this study were to determine whether recombinant human bone morphogenetic protein-2 (rhBMP-2) can be used as the sole stimulator of osteogenesis with success equal to an autologous graft in posterolateral lumbar fusion (PLF) at the same level and to describe the progress until bone union. This study included 11 patients who underwent PLF of L4-5. On the right side, only rhBMP-2, for which polylactic/glycolic acid (PLGA) was used as a carrier, was used, whereas, on the left side, autogenous bone was used. The bone union rate was 73 and 82% at 12 and 24 months after surgery, respectively, on the right BMP side, while the rate on the autogenous bone side was 91%. There was no statistically significant difference in the bone union rate. rhBMP-2 can be used as the sole source of osteogenesis with success equivalent to an autologous graft of the PLF.  相似文献   
756.
Junctional membrane complexes (JMCs) composed of the plasma membrane and endoplasmic/sarcoplasmic reticulum seem to be a structural platform for channel crosstalk. Junctophilins (JPs) contribute to JMC formation by spanning the sarcoplasmic reticulum membrane and binding with the plasma membrane in muscle cells. In this article, we report that mutant JP double-knockout (JP-DKO) mice lacking neural JP subtypes exhibited an irregular hindlimb reflex and impaired memory. Electrophysiological experiments indicated that the activation of small-conductance Ca(2+)-activated K(+) channels responsible for afterhyperpolarization in hippocampal neurons requires endoplasmic reticulum Ca(2+) release through ryanodine receptors, triggered by NMDA receptor-mediated Ca(2+) influx. We propose that in JP-DKO neurons lacking afterhyperpolarization, the functional communications between NMDA receptors, ryanodine receptors, and small-conductance Ca(2+)-activated K(+) channels are disconnected because of JMC disassembly. Moreover, JP-DKO neurons showed an impaired long-term potentiation and hyperactivation of Ca(2+)/calmodulin-dependent protein kinase II. Therefore, JPs seem to have an essential role in neural excitability fundamental to plasticity and integrated functions.  相似文献   
757.
Aim:  To report the stability of parent-perceived child irregular eating from 6 months to 14 years of age and to investigate a predictive model inclusive of child and parent factors.
Methods:  Of the 7223 singleton children in a birth cohort, 5122 children were re-interviewed at 5 years and 4554 for the 14-year analysis. Information was obtained from structured interviews including questions answered by parents of the child at birth, 6 months, 5 years and 14 years; and by teenagers at age 14 years and from physical measures of the child. The mother's perception that the child was an irregular eater at age 14 years was the major outcome variable of interest.
Results:  Approximately 40% of irregular eaters at age 5 will still be irregular eaters at age 14 years. This was not related to maternal education or socio-economic class. Significant at multivariate analysis were infant feeding problems and the children's ability to regulate their sleep and mood. Significant maternal factors were greater age, not feeling positive about the baby and persistent maternal anxiety during the child's early years.
Conclusion:  Irregular eating behaviour displays considerable continuity from childhood to mid-adolescence. Independent contributions to this behavioural phenotype include child biological and psychological factors and maternal anxiety during the child's early years.  相似文献   
758.
Byin situ hybridization histochemistry, expression of mRNAs for the two species of serine/threonine protein kinase Akt, Akt1 and Akt2, were examined in the mouse brain during normal development and in the hypoglossal nucleus following axotomy. On the embryonic days, the gene expression for Akt1 and Akt2 was detected at high levels throughout the entire neuroaxis, then decreased gradually to adult levels during postnatal development. In the adult brain, the gene expression for Akt1 and Akt2 was weak in almost all neurons with no difference of expression levels. The expression level of Akt1 mRNA in the affected hypoglossal nucleus increased dramatically after 48 h to 7 d following axotomy of the hypoglossal nerve, whereas no change was seen in the level of Akt2 mRNA. The present findings suggest that Akt may contribute some important roles not only in neurogenesis, but also in regeneration of injured neuron.  相似文献   
759.
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