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D M Haynes

Publications and source records attributed to D M Haynes.

15 recordsLinked to original sources

A survey of acid catalysts for use in two-step, one-flask syntheses of meso-substituted porphyrinic macrocycles.

[reaction: see text] Diverse Lewis acids and Bronsted acids were examined in the two-step, one-flask synthesis of meso-tetraphenylporphyrin, N-confused tetraphenylporphyrin, and tetraphenylsapphyrin. The scope of acid catalysis was found to be very broad, with 35 of 45 acids providing TPP in yields ranging from 5% to 58%. NC-TPP was also widely observed in yields of 1-40%, and TPS was infrequently observed in yields of <1%. Additionally, conditions were found for direct preparation of magnesium TPP and copper TPP.

Acids, Noncarboxylic↗

An efficient one-flask synthesis of N-confused tetraphenylporphyrin.

[formula: see text] N-Confused meso-substituted porphyrin is a porphyrin isomer previously available from one-flask porphyrin syntheses as a low-yield byproduct (< 7.5%). We have found that methanesulfonic acid catalyzed condensation of pyrrole and benzaldehyde followed by DDQ oxidation provides N-confused tetraphenylporphyrin (NC-TPP) in up to 39% yield in analytical scale experiments. Preparative synthesis provided an isolated yield of 35% (800 mg). This represents a > 5-fold yield improvement and makes significant quantities of NC-TPP readily available.

Chromatography, High Pressure Liquid↗

Patient knowledge of upper respiratory infections: implications for antibiotic expectations and unnecessary utilization.

BACKGROUND: Upper respiratory infections (URIs) account for many of the visits in primary care and are commonly treated with ineffective antibiotic therapy. The purpose of this study was to examine patient beliefs in the effectiveness of antibiotics and the likelihood of seeking care for normal presentations of URIs. METHODS: We conducted a survey of 961 adults (> or = 18 years of age) from an undifferentiated patient population in a university-based family practice residency clinic in metropolitan Kentucky, a private internal medicine practice in nonmetropolitan Kentucky, and, in metropolitan Louisiana, an emergency department and a convenience sample from the community. RESULTS: Seventy-two percent of the sample reported that they would seek care with a condition of 5 days' duration with cough, sore throat, and discolored nasal discharge. Sixty-one percent of the sample expressed their belief that antibiotics are effective for a condition of 5 days' duration with cough, sore throat, and clear nasal discharge; 79% said that they believed antibiotics are effective when there is discolored discharge (P = .0001). Medicaid recipients were most likely to seek care across the symptom complexes. Higher education was related to a decreased belief in the effectiveness of antibiotics for the scenario with clear discharge (P .001), but to an increased belief in the effectiveness of antibiotics in the scenario with discolored discharge (P = .003). The strongest predictor of both likelihood of utilization and belief in effectiveness of antibiotics was usual use of antibiotics for the URI symptom complexes. CONCLUSIONS: Patients lack understanding of the normal presentation of a URI and the effectiveness of antibiotics as a treatment. A confusion about the meaning of discolored nasal discharge is particularly evident, and past antibiotic use may contribute to inappropriate utilization and expectations for antibiotics.

Adult↗

Remember the tune.

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Education, Medical↗

Cesarean hysterectomy: a twenty-five-year review.

This article analyzes cesarean hysterectomies performed at Louisville General Hospital on clinic patients for the 25 year period 1953 through 1977. During this time there were 63,259 deliveries, of which 2417 were cesarean sections and 149 were cesarean hysterectomies. Twenty-six of the latter were classified as emergency operations done for urgent medical indications; in the remaining 123 patients the indications were elective to some degree. Operative and postoperative complications and morbidity are discussed, and changing trends regarding the place of cesarean hysterectomy in obstetrics over the years are evaluated.

Adolescent↗