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Biomedical subjects

P Riley

Publications and source records attributed to P Riley.

At least 73 records · Page 4Linked to original sources
PubMed1987

Mechanism of antitumoral activity of catechols in culture.

Cell lines Raji and K 562, lacking tyrosinase, and two melanotic human melanoma cell lines (IRE 1 and IRE 2), were exposed to concentrations from 5 X 10(-3) M to 10(-5) M of different phenols which are substrates of tyrosinase, i.e. l-dopa, dopamine, hydroquinone, terbutylcatechol, and of phenols which are not substrates of the tyrosinase, i.e. resorcinol, butylated hydroxyanisole and hydroquinone dimethyl ether. Cultures were carried out in the presence or in the absence of oxygen radical scavenger enzymes superoxide dismutase, catalase and peroxidase. The stability of each substance in culture medium was assayed by high performance liquid chromatography (HPLC). Results showed that: catechols which are substrates of tyrosinase decompose fully after 24 hr in medium; they are equally toxic for melanoma and non-melanoma cell lines; their toxicity increases when they are preincubated in medium for 24 hr and 48 hr before addition of cells; their toxicity is significantly reduced by addition of scavenger enzymes; on the contrary, phenols not substrates of tyrosinase are stable in medium and their toxicity is not reduced by scavenger enzymes. It is concluded that tyrosinase does not play a major role in catechol toxicity in vitro, which is probably due to some products of catechol decomposition, especially oxygen radicals, acting outside the cells.

Anisoles↗
PubMed1987

Disembowelment--a retrospective study of patients suffering evisceration following penetrating abdominal injury.

Details are presented of 104 patients admitted over a 1-year period with evisceration following penetrating abdominal wounds. Stabbing was the most common cause of injury. Small bowel was the most commonly eviscerated organ, as well as the organ most frequently injured. Exploratory laparotomy was performed on all the patients who survived to reach the operating theatre. The negative laparotomy rate was 12 per cent, and a further 3 per cent had such mild visceral injuries that they did not require operative repair. For comparison a group of 111 patients admitted over the same period, but suffering only omental protrusion, was also examined. The rate of visceral injury in this group was slightly lower. Wound complications, including breakdown, were more commonly seen in the eviscerated patients, but the mortality was 8 per cent in both groups.

Abdominal Injuries↗
PubMed1987

Computer aids to mammographic diagnosis.

The improvement of mammographic specificity was investigated by means of identifying specific radiological features. Data are presented on the first 500 patients studied who had previously undergone mammography followed by biopsy. The presence of specific mammographic features on each radiograph, first determined by retrospective examination, was entered into a computer database. Subsequent discriminant function analysis demonstrated the importance of a small number of features whose presence could be used in an algorithm to predict diagnostic outcome. Using this algorithm, this feature-identification approach correctly identified 87.6% of benign and 79% of malignant cases. Specificity was improved to 88% as compared with the original radiological diagnosis of 49%. It is argued that this approach is very promising and a computer-assisted diagnosis based on these findings is described.

Algorithms↗
PubMed1985

Growth and development of biofeedback: a bibliographic analysis.

A computerized search was performed, and a bibliography was prepared on the subject of biofeedback covering the years from 1964 to 1985. Growth curves were produced for various publication media. The search produced references to 2,431 journal articles, 102 books, 79 popular magazine articles, and 551 doctoral dissertations. The journal articles were sorted according to the country of publication, language, and primary topic of the journal. Citations were found from 35 countries, written in 18 languages. All the media studied showed a period of rapid growth during the early to middle 1970s, but there was a tendency for leveling off or slight decline during the early 1980s. Publication of articles in medical journals has shown the greatest growth, and more articles are published yearly in medical journals than in journals of any other discipline or all specialty journals combined. Publication in psychological journals has shown a decline since 1977. Dental, nursing, and educational journals have shown a low rate of publication of biofeedback articles, indicating little or no growth.

Academic Dissertations as Topic↗
PubMed1984

Value of serum diazepam and nordiazepam measurements in anxious patients.

The relationship between the dose and anxiolytic effects of diazepam and the serum concentrations of diazepam and nordiazepam were examined in groups of acutely and chronically anxious patients. The results showed a significant correlation between dose and serum nordiazepam concentrations after short-term (14-day) administration, but no significant association between clinical symptoms of anxiety and serum diazepam and nordiazepam. We conclude that the main value of serum benzodiazepine measurements in anxious patients in assessing compliance, particularly in patients suspected of taking more than the recommended dose. Serum nordiazepam is a more consistent index of dosage after chronic therapy than serum diazepam because it has a longer elimination half-time.

Adult↗
PubMed1983

Non-immunological hydrops fetalis. a case report.

A case of hydrops fetalis which was not due to isoimmunization is presented. The condition was diagnosed antenatally by means of ultrasonography and the infant was delivered at 32 weeks' gestation. He required intensive care, but survived and is well at 18 months of age. The causation, diagnosis and management of this problem are discussed.

Adult↗
PubMed1982

Treatment of prolapsed submucous fibroids.

Prolapsed submucous fibroids are not uncommon, and patients present with a vaginal mass which is often necrotic and infected. This is a retrospective study of 41 such patients seen at the King Edward VIII Hospital, Durban, over a 3-year period. Twenty-eight were treated by vaginal myomectomy and 13 by abdominal hysterectomy. Postoperative morbidity was slightly higher with hysterectomy, but comparable to that for hysterectomy for unprolapsed fibroids.

Adult↗
PubMed1979

Sequelae of caffeine treatment in preterm infants with apnea.

Growth, neurologic, and ophthalmologic assessments were done in 21 low-birth-weight infants given caffeine for neonatal apnea and in 21 matched control infants. Caffeine significantly decreased the need for and the duration of mechanical ventilation. No difference in growth and development was noted between the control and caffeine-treated infants. A high incidence of cicatricial retrolental fibroplasia was observed in both control (10/21) and caffeine-treated infants (7/18).

Apnea↗
PubMed1978

Heroin addiction as a family phenomenon: a new conceptual model.

The chronic relapsing nature of heroin addiction can be explained from a family systems viewpoint. The addiction cycle is part of a family pattern involving a complex homeostatic system of interlocking feedback mechanisms. These serve to maintain the addiction and consequently the overall family stability. Drug-taking usually starts at adolescence. It is related to an intense fear of separation experienced by the family in response to the addict's attempts at individuation. The family becomes stuck at a particular developmental stage. Heroin provides a solution at several levels to the dilemma of whether or not to allow him independence. Paradoxically, it permits him to simultaneously be both close and distant, "in" and "out", competent and incompetent, relative to his family of origin. This is pseudoindividuation. An understanding of these concepts, and their integration into a homeostatic model, can provide the basis for effective treatment.

Adolescent↗