Search PubMed⌕ Search

Biomedical subjects

M Johnson

Publications and source records attributed to M Johnson.

At least 739 records · Page 41Linked to original sources
PubMed1983

Some aspects of the relation between theory and research in nursing.

It is suggested that theory can be generated in three principle ways, these being induction, deduction and speculation. The use of these methodological approaches in nursing research and theory construction is briefly examined. The usefulness of theories and models is not doubted, but the extent to which some 'theorists' claim scientific status for their speculations (e.g. Martha Rogers) is deprecated. Finally it is argued that a brief overview of the central problems of epistemology is of value to students of theory and research.

Humans↗
PubMed1983

Severe autosomal recessive muscular dystrophy in an extended Sudanese kindred.

The clinical manifestations, biochemical, electrocardiographic, histological and histochemical features of a severe autosomal recessive muscular dystrophy (MD)--as seen in 15 members of a large Sudanese kindred, both male and female--are reported and discussed. The age of onset ranged from three to five years, the pattern of muscular weakness was similar to that of Duchenne MD and pseudohypertrophy was a remarkable feature. Both sexes became completely dependent by 16 years, and died at or before 20 years of age. The clinical picture in this family and the histological features are compared with those of Duchenne MD and with cases reported from Tunisia, Qatar and Libya. Certain clinical and histological features distinguish all of these types from each other and from the milder autosomal recessive MD of childhood which is more usual in the United Kingdom, Europe, Australia and North America.

Adolescent↗
PubMed1983

Breathlessness and exercise tolerance in chronic airflow obstruction: 2-hourly versus 4-hourly salbutamol by inhalation.

Breathlessness, exercise tolerance, and spirometry were measured in 12 patients whose major symptom was breathlessness, secondary to severe chronic airflow limitation, during a double-blind crossover comparison of inhaled salbutamol in two dosages (200 micrograms 4-hourly and 200 micrograms 2-hourly) with placebo. Daily visual analogue scores of breathlessness, exercise tolerance and spirometry were all significantly improved with salbutamol in both dosages compared to placebo. The 2-hourly regimen was superior to the 4-hourly regimen only in terms of exercise tolerance. Walking distance had deteriorated significantly 2 hours after salbutamol on the 4-hourly regimen and was usefully increased by an extra dose of salbutamol on the 2-hourly regimen at the equivalent time, without side-effects. Salbutamol provided considerable symptomatic relief in addition to spirometric improvement in patients with chronic airflow limitation.

Aged↗
PubMed1983

The effect of clomid induced superovulation on human follicular and luteal function for extracorporeal fertilization and embryo transfer.

The administration of clomiphene citrate (Clomid) 150 mg/day from days 5-9 of the menstrual cycle to spontaneously ovulatory women in order to induce adequate multiple follicular development followed by timed laparoscopic aspiration of mature oocytes does not appear to impair luteal phase length or the steroid pattern of oestradiol-17 beta (E2) or progesterone (P) production as reflected by their peripheral blood concentrations. In Clomid stimulated cycles where preovular oocyte pickup (OPU) and embryo transfer (ET) occurred but no recognizable pregnancy resulted, the cycle length was 30.0 (s.e.m. = 0.3) days, the follicular phase length was 15.6 (s.e.m. = 0.3) days and the luteal phase length was 14.4 (s.e.m. = 0.3) days, which did not differ from a group of women having spontaneous ovular cycles. Following Clomid stimulation the dominant follicle was similar in size to the pre-ovulatory follicle in spontaneous uniovular cycles, but the second, third, fourth and fifth order follicles were significantly larger (P less than 0.0001). The ultimate test of luteal competence was the successful implantation of 11 concepti in 7 women (4 sets of twins) from 49 laparoscopies (14%) or 33 embryo transfers (21%). Comparisons between conceptual and non-conceptual embryo transfers following identical Clomid regimes showed no difference between plasma E2 concentrations at the time of hCG administration or the start of an endogenous LH rise; follicle volume, follicular fluid E2, P and testosterone concentrations were also not different. However, there was a trend for follicular P to be higher in the non-conceptual group indicating that advanced luteinization may hinder successful implantation. The follicular fluid androstenedione (A4) concentration was significantly lower in the conceptual group and the total androgen concentration (A4 + T) was also lower which was indicative of active aromatase activity in these follicles. It was concluded from this study that there was no indication to give exogenous hormonal support to the luteal phase, provided there was both optimal follicular growth and steroidogenic function following Clomid stimulation and that exogenous hCG was administered very close to the expected rise of LH. This observation was supported by the finding that timing of OPU based on a knowledge of the start of the LH surge was associated with a higher pregnancy rate than when hCG was administered and indicates that the endogenous mid-cycle events may permit superior maturation of the oocyte and/or permit better synchronization of endometrial maturation for implantation.

Adult↗
PubMed1982

Effects of in vitro incorporation of cholesterol and cholesterol analogues into rat platelets.

Cholesterol and analogues of cholesterol bearing shorter side chains were incorporated into rat platelet membranes by incubation with sterol-rich liposomes in vitro. Cholesterol-enriched platelets showed increased aggregability to collagen compared with controls. Platelets containing the cholesterol analogues pregn-5-en-3 beta-ol and chol-5-en-3 beta-ol were even more sensitive to aggregation and could aggregate spontaneously on stirring. The size of the platelets containing pregn-5-en-3 beta-ol was markedly reduced when compared with controls in the scanning electron microscope. The results suggest that the sterol content and structure of the platelet membrane can have a critical role in maintaining the normal function of the cell.

Animals↗
PubMed1982

Randomized controlled trial of colestipol in antibiotic-associated colitis.

Thirty-eight patients with severe antibiotic-associated postoperative diarrhoea were entered into a randomized controlled trial to compare colestipol (an ion exchange resin) in 17 patients with placebo (sherbet) in 21 patients. Clostridium difficile or its toxin was present before treatment in 12 of the colestipol group, compared with only 5 in the placebo group. Because of the low incidence of Cl. difficile or its toxin, the placebo group data from 22 patients receiving placebo in a previous trial (9 of whom had Cl. difficile or toxin) were included for comparison. Neither colestipol nor placebo had any influence on the faecal excretion of Cl. difficile or its toxin. Colestipol was clinically no better than placebo. In view of the persistent faecal excretion of Cl. difficile toxin, ion exchange resins cannot be recommended for the treatment of antibiotic-associated colitis.

Anti-Bacterial Agents↗
PubMed1982

Echocardiography in patients with suspected cor pulmonale.

Echocardiography was used to evaluate left ventricular function in 43 consecutive patients with suspected cor pulmonale who clinically had no other heart disease or hypertension. Adequate echocardiographic evidence was obtained by either standard left parasternal position or subxiphoid position in 40 patients (93%). Echocardiographic evidence of either dilatation of the left ventricular cavity or thickening of the right ventricular free wall was present in 37 patients (93%). Small left ventricular end-diastolic cavities suggested that many of these patients had functional left ventricle volume depletion. Echocardiographic evidence of left ventricular dysfunction was present in only three patients (8%).

Adult↗
PubMed1982

Clostridium difficile toxin in acute diarrhoea complicating inflammatory bowel disease.

The incidence of Clostridium difficile cytotoxin has been studied in 69 consecutive patients with inflammatory bowel disease complicated by severe diarrhoea or ileostomy flux during 74 admissions to hospital. The cytotoxin was identified in only four patients, all of whom had received antimicrobials. Clostridium difficle, but not cytotoxin, was identified in 10 of 43 admissions. This followed antimicrobial prophylaxis to cover a recent operation in two patients, and five were on long-term sulphasalazine. Only three patients with Clostridium difficile had not received an antimicrobial within one month of the study. Isolation of Clostridium difficile alone is of doubtful pathological significance, as it spontaneously disappeared without treatment in all patients.

Adult↗