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481.
482.
Arianna Mancuso Ruth Yam Fiorella Prada Marco Stagioni Stefano Goffredo Aldo Shemesh 《Geobiology》2023,21(1):119-132
Stable isotopes in mollusc shells, together with variable growth rates and other geochemical properties, can register different environmental clues, including seawater temperature, salinity and primary productivity. However, the strict biological control over the construction of biominerals exerted by many calcifying organisms can constrain the use of these organisms for paleoenvironmental reconstructions. Biologically controlled calcification is responsible for the so called vital effects that cause a departure from isotopic equilibrium during shell formation, resulting in lower shell oxygen and carbon compared to the equilibrium value. We investigated shell oxygen and carbon isotopic composition of the bivalve Chamelea gallina in six sites along with a latitudinal gradient on the Adriatic Sea (NE Mediterranean Sea). Seawater δ18O and δ13CDIC varied from North to South, reflecting variations in seawater temperature, salinity, and chlorophyll concentration among sites. Shell δ18O and δ13C differed among sites and exhibited a wide range of values along with the ~400 km latitudinal gradient, away from isotopic equilibrium for both isotopes. These results hampered the utilization of this bivalve as a proxy for environmental reconstructions, in spite of C. gallina showing promise as a warm temperature proxy. Rigorous calibration studies with a precise insight of environment and shell growth are crucial prior to considering this bivalve as a reliable paleoclimatic archive. 相似文献
483.
Doroti Pirulli Daniela Puzzer Laura Ferri Sergio Crovella A. Amoroso Cristina Ferrettini Martino Marangella Gina Mazzola Fiorella Florian 《Human genetics》1999,104(6):523-525
Systematic screening using the SSCP technique followed by sequencing of bands with abnormal mobility derived from the AGXT exons of 15 unrelated Italian patients with primary hyperoxaluria type 1 (PH1) allowed us to characterize both the mutant
alleles in each individual. Eight new mutations were identified: C155del, C156ins, G244T, C252T, GAG408ins, G468A, G588A and
G1098del. This study demonstrates both the effectiveness of the screening strategy chosen to identify all the mutant alleles
and the high degree of allelic heterogeneity in PH1.
Received: 5 January 1999 / Accepted: 12 April 1999 相似文献
484.
Maria G. Cancedda Giovanni Di Guardo Roberto Chiocchetti Francesca Demontis Giuseppe Marruchella Caterina Sorteni Caterina Maestrale Alfio Lai Ciriaco Ligios 《Journal of virology》2014,88(2):1065-1070
Atypical and classical scrapie-infected sheep brain tissue was monolaterally injected into the tonsils of lambs to investigate their role as a prion entry point. We first detected classical PrPSc within the inoculated tonsil and in the ipsilateral retropharyngeal lymph node at 3 months postinoculation (p.i.). At 7 months p.i., PrPSc colonized other lymphoid tissues bilaterally, including ileal Peyer''s patches. The earliest PrPSc deposition within the brain was ipsilaterally observed at 9 months p.i. in the substantia reticularis of the medulla oblongata. At 12 months p.i., PrPSc deposition was present bilaterally in the nucleus parasympathicus nervi vagi, as well as in the intermediolateral cell column of the thoracolumbar spinal cord. No PrPSc was detected in the lambs inoculated with atypical scrapie. These findings suggest that neuroinvasion may naturally occur from the tonsil after a widespread prion replication within the lymphoid tissues during classical scrapie only, thus mimicking the pathogenesis after oral ingestion. 相似文献
485.
486.
Prevalence,characteristics, and survival of children with esophageal atresia: A 32‐year population‐based study including 1,417,724 consecutive newborns 下载免费PDF全文