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Biomedical subjects

S Hoffman

Publications and source records attributed to S Hoffman.

At least 217 records · Page 12Linked to original sources
PubMed1977

Purification and partial characterization of deoxyribonuclease I from bovine parotid gland.

Deoxyribonuclease I has been purified from bovine parotid gland. The purification procedure utilizes an acid extraction of minced parotid gland, salt fractionation, gel filtration, and ion-exchange chromatography. The last step, chromatography on Sulfopropyl-Sephadex, resolves the enzymatic activity into several fractions. The major fraction, designated DNase A, was subjected to further investigation. This enzyme has, as expected, an alkaline pH optimum and an obligate requirement for divalent cations. The presence of calcium chloride protects DNase A from inactivation by proteolytic enzymes. Despite the previously described immunologic dissimilarity, there appears to be a large amount of homology between the parotid and pancreatic DNase's.

Amino Acids↗
PubMed1977

Antiplaque potential of topical stannous fluoride.

Sterile enamel samples treated by topical application of 10% stannous fluoride were incubated with S mutans and S sanguis respectively and with a mixed culture to which L casei had been added. The results were compared with sterile nonfluoridated enamel samples subjected to the same procedures. The parameters compared were postincubation pH values, bacterial concentrations on the surfaces, and enamel surface alterations. Stannous fluoride treated samples consistently yielded higher pH readings than nonfluoridated samples; the concentration of microorganisms adhering to the surfaces was conspicuously reduced on the pretreated enamel when compared by scanning electron microscopy to untreated samples, as were enamel surface alterations. These findings lend support to other recent investigations which have shown that fluorides act in several ways to inhibit cariogenesis in addition to reducing hydroxyapatite solubility.

Adult↗
PubMed1977

Marital instability and the economic status of women.

This paper uses longitudinal data from the Panel Study of Income Dynamics to examine the relationship between changes in marital status and economic status. Differences between men and women and between whites and blacks are also considered. A major finding is that, after adjusting for changes in family size, the economic status of divorced or separated men improves, while that of women declines. Components of income change are discussed, with special emphasis on changes in the labor force and welfare status of women who were divorced or separated during the analysis period. Finally, data on the magnitude and distribution of alimony/child-support payments are presented.

Child Care↗
PubMed1976

Low lead levels and mental retardation.

Borderline and mildly retarded children attending the hospital developmental evaluation clinic were divided into two groups on the basis of the presence or absence of a pred with a paediatric control group using blood-lead concentration as the independent variable. Children with a history of diagnosed lead posisoning were excluded from the study. The group of mentally retarded children "aetiology unknown" had statistically significantly raised blood-lead concentrations but the mentally retarded sample with "probable aetiology" showed no significant difference in lead concentrations from those of the normal controls. It is concluded that the association between lead and mental retardation extends over a much wider range than hitherto suspected and that the nature of this association is independent of a history of "encephalopathic" lead poisoning. It is suggested that physicians should consider raised lead levels in their examination of all children suspected of mental retardation and that the numerical definition of lead toxicity should be re-evaluated.

Child↗
PubMed1976

Delayed lumen obstruction in endotracheal tubes.

Delayed onset of obstruction in the Oxford endotracheal tube during anaesthesia is described in five patients. The effects of intra-cuff voluem and pressure on the wall of the tube were investigated and discussed with special refernce to the ffects of body heat and repeated use on the consistency of the tube. It is concluded that inward collapse of the tube wall is caused by a combination of factors, namely: frequent use, softening of the tube wall by body heat, the gradual increasing of intra-cuff volume and pressure by diffusion of nitrous oxide into the cuff, replacing a damaged cuff by a new one and heat sterilization. Deflation and re-inflation of the cuff to minimal occlusive volume at hourly intervals is suggested as a precautionary measure in the prevention of inward collapse of the tube wall.

Airway Obstruction↗
PubMed1976

Squamous cell carcinoma of the oral soft tissues: a statistical analysis of 14,253 cases by age, sex, and race of patients.

Squamous cell carcinoma is the most frequently occurring malignant tumor of the oral structures, accounting for about 90% of the total number of malignant oral lesions. Among 14,253 cases of soft tissue squamous cell carcinomas of the oral area in the files of the Armed Forces Institute of Pathology, the most common locations are the lower lip (38% of the cases) and the tongue (21%). In the past few years, however, the number of carcinomas of the floor of mouth has been increasing. Our material also shows a definite trend of the carcinomas to develop in patients of an age group 10 years younger than has been previously reported.

Adolescent↗