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Biomedical subjects

A Sharon

Publications and source records attributed to A Sharon.

At least 37 records · Page 2Linked to original sources
PubMed1992

Isolation, Purification, and Identification of 2-(p-Hydroxyphenoxy)-5, 7-Dihydroxychromone: A Fungal-Induced Phytoalexin from Cassia obtusifolia.

A single phytoalexin was isolated and purified from 12- to 14-day-old leaves of Cassia obtusifolia L. inoculated with Alternaria cassiae Jurair & Khan. The structure was elucidated by (1)H- and (13)C-nuclear magnetic resonance and mass spectrometry as 2-(p-hydroxyphenoxy)-5,7-dihydroxychromone. The compound was shown to be derived in part from phenylalanine. Radial growth of A. cassiae was inhibited 50% by the compound at 0.3 millimolar. This moderate toxicity is compensated for by the relatively high levels (3 millimolar) accumulated. Phenoxychromones have been previously reported only as constitutive secondary metabolites in Artemisia capillaris Thunb., in which their function is unknown.

Journal Article↗
PubMed1992

Glyphosate Suppression of an Elicited Defense Response : Increased Susceptibility of Cassia obtusifolia to a Mycoherbicide.

The major effort in developing pathogenic fungi into potential mycoherbicides is aimed at increasing fungal virulence to weeds without affecting crop selectivity. Specific suppression of biosynthesis of a phytoalexin derived from the shikimate pathway in Cassia obtusifolia L. by a sublethal dose (50 micromolar) of glyphosate increased susceptibility to the mycoherbicide Alternaria cassiae Jurair & Khan. Glyphosate applied with conidia suppressed phytoalexin synthesis beginning at 12 hours, but not an earlier period 8 to 10 hours after inoculation. The phytoalexin synthesis elicited by fungal inoculation was also suppressed by darkness. The magnitudes of virulence of the mycoherbicide in the dark or with glyphosate in the light were both higher than after inoculation in the light with the same concentration of conidia in the absence of glyphosate. Five times less inoculum was needed to cause disease symptoms when applied with glyphosate than without. Glyphosate did not render A. cassiae virulent on soybean (Glycine max), a crop related to the host. These results suggest that a specific inhibition of a weed's elicited defense response can be a safe way to enhance virulence and improve the efficacy of the mycoherbicide.

Journal Article↗
PubMed1986

Dust levels in an asbestos-cement factory: problem solving.

Isasbest Ltd., an asbestos-cement factory in Israel, has established dust-preventive measures, maintained high ecological and medical standards, and assisted afflicted workers suffering from asbestos-related diseases. The problems of the handling of asbestos and its relationship to health should be approached according to the conditions in each specific workplace so that reasonable solutions can be found for proper control.

Air Pollution↗
PubMed1984

Primary malignant melanoma of the mandibular gingiva.

A rare case of a primary malignant melanoma of the mandibular molar area in a young adult is described. Widespread metastases as well as local recurrence developed within 9 months in spite of an aggressive surgical approach combined with immuno- and chemotherapy.

Adult↗
PubMed1981

Dental extractions during anticoagulant therapy.

1. 15 patients, whose therapy with the anticoagulant Coumarin was not discontinued, were observed for bleeding following dental extractions. 2. There was no significant bleeding in these patients as compared to 15 others whose Coumarin therapy was temporarily interrupted. 3. Patients with prosthetic heart valves should preferably be hospitalized for dental extractions. but Coumarin/anticoagulant therapy need not be discontinued. The procedures can safely be done within a therapeutic range of 20-30% P.T.

Adult↗
PubMed1977

The effect of chlorhexidine mouth rinses on oral Candida in a group of leukemic patients.

Eighteen leukemic patients were examined for the presence of Candida albicans in the oral cavity. Fifteen patients were found to be Candida "carriers." Nine of the patients were put on a chlorhexidine mouth rinse regimen. Although chlorhexidine was clearly fungicidal in vitro, no decrease in Candida titer was obtained with the mouth rinse. The ineffectiveness of the drug in vivo might be due to the specific location of Candida organisms in the oral mucosa.

Biguanides↗
PubMed1976

Patient motivation and response to surgical correction of prognathism.

Twenty-five patients operated upon between 1969 and 1973 for correction of mandibular prognathism were recalled in 1975 and asked to evaluate their attitudes toward the procedure and the postoperative results. All but one were satisfied with the results. Postoperative numbness of the lip and chin lasting more than 6 months was commonly noted following the intraoral sagittal split method. This did not influence the patient's satisfaction with the operation. The minimal postoperative scar following the extraoral oblique osteotomy was not a negative factor. Most patients underwent the surgical procedure for esthetic reasons. A large number (68 per cent) noted a change in personality postoperatively. A rationale for selective preoperative psychologic counseling is suggested.

Consumer Behavior↗