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Biomedical subjects

A Mariani

Publications and source records attributed to A Mariani.

At least 73 records · Page 4Linked to original sources
PubMed1982

Proximal and accommodative convergence and age.

The authors have estimated the phoria for distant and near fixation in two groups of subject (mean age 27. 5+/- 4.4 and 59.2 +/- 8.2 years). Different accommodative stimuli were induced by adding minus lenses for distant fixation and plus lenses for near fixation. Statistical analysis of the experimental data indicates that, for distant fixation, the value of phoria per unit of accommodative stimulus is significantly lower presbyopic than in nonpresbyopic subject. Also, during near fixation, the accommodative convergence (AC/A ratio) is more reliable in the presbyopic subjects when the accommodative stimulus is progressively reduced. This varying behavior indicates in presbyopic subjects that proximal convergence is of greater relative importance in the determination of the fusion-free position. In nonpresbyopic subjects, accommodative convergence is the more important component.

Accommodation, Ocular↗
PubMed1981

Fluorescence assays and pharmacokinetic studies of 4'-deoxydoxorubicin and doxorubicin in organs of mice bearing solid tumors.

The pharmacokinetic of 4'-deoxydoxorubicin, a new analog of doxorubicin, was compared with that of its parent compound in mice treated with equal and equiactive doses. The levels of total fluorescence due to the initial drugs and to metabolites were determined in tissue extracts by fluorometry. 4'-Deoxydoxorubicin reached the same tissue levels as doxorubicin in all the organs tested except in spleen and lung, where a higher peak was found in the animals treated with the new analog. The rate of elimination of 4'-deoxydoxorubicin from the organs tested was higher than that of doxorubicin.

Animals↗
PubMed1980

A second type of horizontal cell in the monkey retina.

A second type of horizontal cell with a distinctly different appearance from the previously known horizontal cell has been seen in Golgi-impregnated monkey retinas. The new HII cell has a different dendritic branching pattern from the commonly described HI cell type, and it has a short convoluted axon with collaterals bearing small clusters of terminals. Comparisons of the two cell types at different retinal eccentricities show that HII cells have larger dendritic trees than HI cells in the foveal region but smaller dendritic trees than HIs in peripheral retina. Dendritic terminals of the new HII cell, like the HI cell, contact cone pedicles as lateral elements of the ribbon synapses. The isolated terminals or clusters of terminals borne by the short axon of the HII cell also contact cone pedicles as lateral elements rather than contacting rod spherules as lateral elements like HI terminal arborizations. Thus, the monkey like other vertebrates has at least two horizontal cell types which differ in morphology and synaptic connections.

Animals↗
PubMed1980

Mercury levels in food and its intake in high-risk population groups.

The mercury levels in many diet samples collected in 5 groups of normal Italian adult population were measured and compared to those referred to an area well known for its high environmental mercury content. In the same subjects, the hair and blood concentration of mercury was evaluated and related to the dietary intake. In fact, the somatic and cytogenetic effects due to the mercury contamination are mainly correlated with the blood and hair content of mercury. Significant cytogenetic effects were detected in a group of subjects exposed to elemental mercury vapor, thus showing an average mercury concentration in the blood of about 45 micrograms/ml. On the basis of the mercury content in the diet and in the blood of both the Italian population groups and the population group of the high mercury area, it can be argued that significant somatic and cytogenetic effects are undetectable at those mercury exposures, thus confirming that a daily intake of 10-40 micrograms mercury can be considered as an acceptable level for the normal population as suggested by WHO.

Adult↗
PubMed1979

Fluorescence assay of tissue distribution of 4-demethoxydaunorubicin and 4-demethoxydoxorubicin in mice bearing solid tumors.

The tissue distribution of 4-demethoxydaunorubicin and 4-demethoxydoxorubicin was studied in comparison with that of their patient compounds, daunorubicin and doxorubicin, in mice bearing transplanted tumors. The doses administered were equal or equitoxic to those of their parent compounds. The levels of total fluorescence due to initial drugs and metabolites were determined on tissue extracts by fluorometry. After administration of equal doses of daunorubicin and 4-demethoxydaunorubicin, the calculated Cxt values of 4-demethoxydaunorubicin equivalents were higher than those for daunorubicin in all the organs tested except the heart. In animals treated with equitoxic doses, lower 4-demethoxydaunorubicin levels were found in all the organs tested. In mice treated with equitoxic doses of doxorubicin and 4-demethoxydoxorubicin, 4-demethoxydoxorubicin reached higher drug concentrations than doxorubicin in spleen and liver, whereas in all the other organs tested lower drug levels were found. The rate of drug disappearance from organs was slower in animals treated with 4-demethoxyderivatives than in those treated with their parent drugs.

Animals↗