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D Edwards

Publications and source records attributed to D Edwards.

At least 73 records · Page 4Linked to original sources
PubMed1986

The spasmogenic action of oxytocin in the rat uterus--comparison with other agonists.

A low concentration (0.2 nM) of oxytocin induced phasic tension development in the isolated uterus of the day-22 pregnant rat. Tonic spasm was also induced by higher concentrations of oxytocin (2 and 20 nM). Spasmogenic responses to bradykinin and potassium chloride (KCl) also contained phasic and tonic components while acetylcholine induced tonic spasm only. The phasic component of the responses to oxytocin and to bradykinin and both components of the response to KCl were inhibited by (+)-cis diltiazem (0.1 and 1 microM). The tonic component of the responses to oxytocin and to bradykinin and the responses to acetylcholine were only reduced by (+)-cis diltiazem at concentrations greater than 10 microM. (-)-cis Diltiazem was less potent than (+)-cis diltiazem as an inhibitor of calcium (Ca2+)-induced spasm in a depolarizing medium and of the phasic spasms induced by oxytocin. The two isomers were of similar potency as inhibitors of oxytocin-induced tonic spasm. Spasmogenic responses to oxytocin, bradykinin, acetylcholine and KCl were decreased when uteri were bathed in media which were Ca2+-free or of low Na+ content. However, there was no correlation between the rank order of sensitivity of the four spasmogens to the changed media and to their inhibition by (+)-cis diltiazem. Oxytocin (0.2 nM) increased the frequency, duration and amplitude of spike activity, measured by extracellular electrical recording, in parallel with enhancement of phasic tension development. With higher concentrations of oxytocin (2 and 20 nM) spike firing was initially continuous but often subsequently ceased despite the associated tonic contracture. After incubation in (+)-cis diltiazem (10 microM), oxytocin (0.2, 2 and 20 nM) produced graded tonic spasm without spike activity. Oxytocin (0.2 nM) produced a small increase in 45Ca2+ influx into myometrium as assessed by the 'lanthanum method'. Higher concentrations of oxytocin (2 and 20 nM) did not increase 45Ca2+ influx. It is concluded that the phasic component of the response of the uterus to oxytocin and bradykinin is associated with Ca2+ influx via voltage-dependent Ca2+ channels. The tonic component is due to another mechanism(s) which does not appear to involve Ca2+ influx. All of the spasmogenic response to KCl can be explained by Ca2+ influx through voltage-dependent Ca2+ channels. These channels do not appear to be involved in the spasmogenic response to acetylcholine.

Acetylcholine↗
PubMed1986

Association between diaphragm use and asymptomatic bacteriuria.

The prevalence of asymptomatic bacteriuria was assessed in women using different contraceptive methods. Three hundred and twenty women attending a family planning centre were studied, 80 in each of the following groups: diaphragms, intrauterine contraceptive devices (IUCDs), oral contraceptives (OCs) and no contraception. The numbers with asymptomatic bacteriuria in the 4 groups were as follows: diaphragm - 12 (all E coli); IUCD - 3 (E coli; P mirabilis; S saprophyticus); OC - 5 (all E coli); no contraception - 4 (3 E coli; 1 S saprophyticus). The prevalence of Gram-negative bacteriuria in women using diaphragms was significantly higher than for women in the other groups (chi 2 = 8.98; p less than 0.05). Factors such as parity, numbers of sexual partners and frequency of sexual intercourse had no apparent effect. The use of diaphragms may contribute to the risk of Gram-negative urinary tract infections in sexually active women.

Adolescent↗
PubMed1986

Cardiogenic shock without a critically raised left ventricular end diastolic pressure: management and outcome in eighteen patients.

Eighteen patients in whom shock developed after acute myocardial infarction are described. There was electrocardiographic evidence of acute inferior infarction in 11, of inferolateral infarction in three, and of anteroseptal infarction in four. In all cases the right atrial pressure was the same as or exceeded the end expiratory pulmonary artery wedge pressure. Plasma volume expansion of 100-2500 ml was needed to produce an optimum pulmonary artery wedge pressure. Eleven patients needed additional inotropic support with dopamine. Despite the absence of a critical increase in pulmonary artery wedge pressure, potential or actual hypoxia was almost always present. Six patients needed endotracheal intubation and mechanical ventilation because they had severe hypoxia that was unresponsive to supplemental inspired oxygen. Life threatening arrhythmias were also common (ventricular fibrillation in seven patients and complete heart block in four). Five patients died. All surviving patients are well and only one requires treatment for heart failure.

Aged↗
PubMed1986

The role of computerised tomography in intervertebral disc prolapse.

Computerised tomography of the lumbar spine was performed on 22 patients with clinical evidence of prolapse of an intervertebral disc and normal or equivocal radiculograms. Of 11 patients with positive scans who had an operation the presence of pathology was confirmed in 10. Although CT scanning is always helpful in diagnosing disc disorders, where facilities are scarce (as in Great Britain) it is best employed in patients with negative or non-contributory radiculography.

Adult↗
PubMed1985

Development of new renal scars: a collaborative study.

In a study of the factors surrounding the development of renal scars clinical data and serial radiographs were analysed in 74 infants and children (66 girls and eight boys) without duplex kidney or obstruction. The development of new scars was seen radiologically in 87 kidneys (74 previously normal and 13 previously scarred). New scarring was extensive in 16 kidneys. Thirty four children were aged 5 or over when scarring occurred. Urinary infection occurred in all the children. Diagnosis and effective treatment were delayed in 45 of them; 58 suffered further urinary infections between the baseline intravenous urogram and the first showing new scarring. Vesicoureteric reflux was seen in 67 of the children. Investigation and treatment varied widely, and few children received long term prophylaxis. Social problems interfered with the management of 22 children. Early diagnosis, prompt effective treatment, investigation, and long term supervision of children with urinary infection are essential if renal scarring is to be reduced; those over the age of 5 are still vulnerable.

Child↗
PubMed1985

Chlamydia trachomatis infection at a family planning clinic.

Endocervical samples were taken for the detection of Chlamydia trachomatis from 500 consecutive patients attending a family planning clinic. The Microtrak direct specimen immunofluorescence test was used. Swabs from 79 patients (15.8%) were positive for chlamydia. Seventy-one (95%) of these patients were symptom free, and 39.8% were under 20 years old. Twenty-one patients were pregnant, seven (33%) had chlamydia. Those positive for chlamydia had twice the frequency of abnormal smears and other sexually transmitted infections as those who were negative. Contraceptive use was similar except that intrauterine devices were used less frequently by patients with chlamydia infection. This report indicates the frequent occurrence of Chlamydia trachomatis infection in New Zealand and that newly developed methods of diagnosis enable us to identify and treat those with this infection. Characteristically these patients are under 20, have multiple partners and a high incidence of abnormal smears and other sexually transmitted infections.

Adolescent↗
PubMed1985

Exogenous human surfactant for treatment of severe respiratory distress syndrome: a randomized prospective clinical trial.

We performed a randomized, prospective clinical trial comparing intratracheal administration of human surfactant with conventional treatment with intermittent mandatory mechanical ventilation alone for treatment of severe respiratory distress syndrome in preterm infants of less than 30 weeks gestation. Twenty-two infants (mean gestational age 27.0 weeks, mean birth weight 987 gm) were given surfactant, and 23 infants (mean gestational age 27.2 week, mean birth weight 1055 gm) received intermittent mandatory ventilation. Infants given surfactant required less FiO2 during the first week, had lower mean airway pressure during the first 48 hours, and had improved ventilatory index and a/A PO2 ratio. Death or the occurrence of bronchopulmonary dysplasia was significantly less among infants given surfactant (P = 0.019). Pneumothorax, pulmonary interstitial emphysema, and need for FiO2 greater than or equal to 0.3 for greater than 30 days was significantly less in the surfactant group. This trial confirms the efficacy of treatment with human surfactant in preterm infants with severe respiratory distress syndrome.

Amniotic Fluid↗
PubMed1985

High-dose cyclophosphamide in small-cell carcinoma of the lung.

Eighteen patients with untreated small-cell cancer of the lung have been treated with cyclophosphamide 200 mg/kg on two occasions at an interval of four weeks. An additional eight patients received etoposide in addition to cyclophosphamide. Measurements of tumor volume were made by thoracic computed tomographic (CT) scan before and after each cycle. When compared with our previous study in which only one cycle of cyclophosphamide was given, the double procedure did not increase response rate, decrease the incidence of local relapse, or prolong the relapse-free interval. Survival after relapse was shorter with two cycles of chemotherapy mainly due to greater difficulty in administering further chemotherapy. The CT scans showed a decrease in tumor volume from 99.2 cc to 21 cc after the first cycle, but a smaller decrease to 14.1 cc after the second. These results show that the rapid emergence of drug resistance imposes limitations on the use of very high-dose cytotoxic chemotherapy.

Adult↗
PubMed1984

Jail nurse.

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Nursing Care↗
PubMed1983

Non-metabolizable amino acids are potent stimulators of hepatic and renal ornithine decarboxylase activity.

The non-metabolizable amino acids alpha-aminoisobutyric acid (AIB) and cycloleucine and the poorly metabolizable amino acid D-alanine potently stimulated hepatic ornithine decarboxylase (ODC) activity in starved rats. The stimulation by AIB was shown to have several of the characteristics of stimulation by a protein meal and occurred in hypophysectomized animals. AIB also stimulated renal, but not brain or heart, ODC activity.

Alanine↗
PubMed1983

Preoperative staging of lung cancer: accuracy of computed tomography versus mediastinoscopy.

Forty-four patients coming to surgery for carcinoma of the bronchus underwent preoperative staging of the mediastinum by computed tomography (CT scanning) and surgical exploration of the mediastinum by cervical mediastinoscopy or left anterior mediastinotomy or both. Where mediastinal nodes were affected the sensitivity and specificity of computed tomography was inferior to that of mediastinoscopy (57% and 85% versus 71% and 100%). The sensitivity of computed tomography in predicting mediastinal invasion was superior to that of mediastinoscopy (77% v 46%), especially in the case of lower-lobe tumours (67% v 17%). Mediastinoscopy had the considerable advantage of 100% specificity. In the assessment of hilar lymphadenopathy computed tomography had a sensitivity of 38% and a specificity of 64%. In cases where computed tomography showed a normal mediastinum or enlargement of the hilar glands only, mediastinal exploration conferred no additional information and could have been omitted. A computed tomography scan showing mediastinal abnormality is an indication for mediastinoscopy and not a contraindication to surgery. In 23 patients computed tomography showed some abnormality of the mediastinum, confirmed at mediastinoscopy in 12 cases. The remaining 11 patients underwent thoracotomy, resection being carried out in nine. Postsurgical staging showed that six of these tumours were N0 lesions without invasion; in two further N0 cases there was a minor degree of mediastinal invasion which did not prevent resection, and the remaining tumour was N1 without invasion.

Aged↗