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81.
Diet and attrition in the Natufians 总被引:1,自引:0,他引:1
P Smith 《American journal of physical anthropology》1972,37(2):233-238
There is a high correlation between the rate of dental attrition and the physical consistency of the diet. Hypotheses concerning types of diet and methods of food preparation in prehistoric populations may therefore be tested by comparing attrition rates in the specimens under investigation with standards derived from groups of known dietary status. For such comparisons the age factor is of paramount importance, but difficult to assess accurately in fragmentary skeletal material. The use of attrition gradients rather than mean attrition scores provides an age independent method for comparison of attrition rates. When Natufian specimens from three different sites (Kebara, El Wad and Eynan) were compared by this method, significant differences in the gradient of attrition were found at one site, Kebara. The incidences of caries and periodontal disease were also lower at this site, and taken in conjunction with the low level of attrition were considered to relate to differences in the vegetable content of the diet between the individuals recovered from Kebara and those recovered from El Wad and Eynan. 相似文献
82.
A A Lackner P F Moore P A Marx R J Munn M B Gardner L J Lowenstine 《Journal of medical primatology》1990,19(3-4):339-349
Type D retrovirus infection of rhesus macaques (Macaca mulatta) shares many features with AIDS in man including gastrointestinal signs such as chronic diarrhea and wasting. In some humans and macaques afflicted with these signs and symptoms no etiology can be established. In this study immunohistochemistry was employed to localize D/1/California in the digestive tract of ten animals with simian AIDS. This revealed that both epithelial and lymphoid cells of the digestive tract are commonly infected by this immunosuppressive type D retrovirus. 相似文献
83.
84.
85.
C P Ogbourne 《International journal for parasitology》1975,5(4):423-426
Observations are reported on the size and age structure of Stronglyus vulgaris populations recovered from the anterior mesenteric artery and its main branches of horses slaughtered at regular intervals throughout a year. Marked seasonal variations were found in the mean monthly numbers of worms present. During spring/early summer the numbers were relatively low and a large proportion of the arteries had no worms in them at all. Thereafter, the arterial worm burdens quite rapidly increased and the highest levels were reached during the winter months. During summer, small, newly-arrived larvae were quite abundant but by the end of the year well-developed (fifth-stage and late fourth-stage) worms predominated. These observations support the view that S. vulgaris is in Britain an annual species completing its development mainly during the winter months of the year. 相似文献
86.
87.
zge Karayel Francesca Tonelli Sebastian Virreira Winter Phillip E. Geyer Ying Fan Esther M. Sammler Dario R. Alessi Martin Steger Matthias Mann 《Molecular & cellular proteomics : MCP》2020,19(9):1546-1560
Highlights
- •MS-based clinical assay that accurately determines phospho Rab10 occupancy.
- •Stable isotope labeled phosphopeptide injected as a standard with endogenous tryptic phospho Rab peptide for accurate ratio determination.
- •Determination of pRab levels in neutrophils of Parkinson disease patients.
- •Relevance of pRab levels as marker of PD.
88.
《Molecular & cellular proteomics : MCP》2020,19(3):518-528
Highlights
- •Discovery of peptide biomarker candidates of respiratory tract pathogens S. pneumoniae, H. influenzae, M. catarrhalis and S. aureus as target pathogens.
- •Peptide biomarker candidates were experimentally verified in clinical samples.
- •Targeted MS using promising peptide biomarker candidates shown as proof-of-concept.
89.
Abstract: To investigate the regulation of posttranslational modifications of τ that might be pertinent to the production of the paired helical filament (PHF) of Alzheimer's disease, we incubated human neuroblastoma cells with the protein phosphatase inhibitor okadaic acid. This treatment results in increased immunoreactivity of τ with the monoclonal antibodies Alz-50, PHF-1, T3P, and NP8, a reduction in Tau-1 immunoreactivity, and an elevation in apparent molecular weight of τ. Moreover, our data demonstrate that accumulation of phosphates in τ leads to a decrease in the turnover rate of τ in the neuroblastoma cells. It is suggested that similar build-up of hyperphosphorylated τ in the neuronal perikarya may represent an early event in PHF formation. The present system facilitates the investigation of regulatory mechanisms governing the occurrence of PHF epitopes, their effects on neuronal cell metabolism, and possible pharmacological intervention. 相似文献
90.
Anny Cárdenas Luis M Rodriguez-R Valeria Pizarro Luis F Cadavid Catalina Arévalo-Ferro 《The ISME journal》2012,6(3):502-512
Coral reefs are deteriorating at an alarming rate mainly as a consequence of the emergence of coral diseases. The white plague disease (WPD) is the most prevalent coral disease in the southwestern Caribbean, affecting dozens of coral species. However, the identification of a single causal agent has proved problematic. This suggests more complex etiological scenarios involving alterations in the dynamic interaction between environmental factors, the coral immune system and the symbiotic microbial communities. Here we compare the microbiome of healthy and WPD-affected corals from the two reef-building species Diploria strigosa and Siderastrea siderea collected at the Tayrona National Park in the Caribbean of Colombia. Microbiomes were analyzed by combining culture-dependent methods and pyrosequencing of 16S ribosomal DNA (rDNA) V5-V6 hypervariable regions. A total of 20 410 classifiable 16S rDNA sequences reads were obtained including all samples. No significant differences in operational taxonomic unit diversity were found between healthy and affected tissues; however, a significant increase of Alphaproteobacteria and a concomitant decrease in the Beta- and Gammaproteobacteria was observed in WPD-affected corals of both species. Significant shifts were also observed in the orders Rhizobiales, Caulobacteriales, Burkholderiales, Rhodobacterales, Aleteromonadales and Xanthomonadales, although they were not consistent between the two coral species. These shifts in the microbiome structure of WPD-affected corals suggest a loss of community-mediated growth control mechanisms on bacterial populations specific for each holobiont system. 相似文献