PubMed Health⌕ Search

Biomedical subjects

D Powell

Publications and source records attributed to D Powell.

At least 127 records · Page 7Linked to original sources
PubMed1982

Patterns of contraceptive use in Kingston and St Andrew, Jamaica, 1970--1977.

The records of a sample of Family Planning acceptors were examined to identify those factors which influenced the choice of a contraceptive and the drop-out rate in the period 1970--1977 inclusive. It was found that although a full range of contraceptives was theoretically available, as the 1970s advanced the effective choice appeared to lie between the two hormonal contraceptives, medroxyprogesterene acetate (Depo Provera) and the oral contraceptive pill with family size being the deciding factor. The drop-out rate as also influenced by family size with nulliparous women showing the highest rate. Explanations for the drop-out rates and the percentage of single visits made to the clinics were sought through the utilization of partial correlations. In both cases the average distance between the acceptor's home and the clinic appeared to play a decisive role.

Adolescent↗
PubMed1982

Hypercalcitoninaemia in medullary carcinoma of the thyroid and other malignancies: value of calcitonin as tumour marker.

Elevated plasma calcitonin was detected by radioimmunoassay in 19 of 99 unselected cancer patients (19%). The frequency of hypercalcitoninaemia in patients with tumours of lung, uterus, gastrointestinal tract, and urinary bladder was about 40%, in carcinoma of the breast 18%, and in carcinoma of the skin 4%. In 8 patients with bone metastases, 4 were hypercalcitoninaemic. None of 19 patients with non-malignant disorders had elevated plasma calcitonin. The highest plasma calcitonin level in cancer patients was 8200 ng/l. Urinary cyclic AMP was elevated in patients with hypercalcitoninaemia as compared with patients with normal plasma calcitonin. All 6 patients with medullary carcinoma of the thyroid had very high plasma calcitonin levels: more than 50000 ng/l in five and 30000 ng/l in one patient. Of the family members of these patients, raised plasma calcitonin was detected after stimulation with oral alcohol in 6 of 12. It is concluded that plasma calcitonin levels in excess of 10000 ng/l suggest the presence of medullary carcinoma of the thyroid, while levels below 10000 ng/l have a poor diagnostic value but should alert the clinician to look for a possible malignancy.

Calcitonin↗
PubMed1982

Immunoreactive substance P content in median eminence and pituitary gland during oestrus, dioestrus and after anterior hypothalamic deafferentation.

The aim of the present study was to find a relation between the Substance P (SP) content in the median eminence and the pituitary gland in rats and hypothalamic regulaton of the oestrus cycle. SP content was measured by radioimmunoassay in female rat pituitary and median eminence during oestrus, dioestrus and after anterior hypothalamic deafferentation. SP content in rat's pituitary did not vary significantly among individual groups of animals. The greatest average SP content in rat's median eminence was found in dioestrus. Both during cyclic and constant oestrus resulting from anterior hypothalamic deafferentation SP content in median eminence was lower than in dioestrus. This fact indicates the possibility of SP involvement in the control of cyclic LH-RH release from hypothalamus.

Animals↗
PubMed1981

Substance P-like immunoreactivity in the nervous system of hydra.

Using immunocytochemistry we find substance P-like material in nerve cells of hydra. These nerve cells are situated in the ectoderm of the basal disk and tentacles. Radioimmunoassay of hydra extracts gives dilution curves parallel to that of synthetic substance P, from which it can be calculated that one animal contains at least 0.6 fmol substance P-like immunoreactivity. After chromatography on Biogel P-100, the substance P-like immunoreactivity elutes as a peak in the void volume and a peak at the position of synthetic substance P.

Animals↗
PubMed1981

Herpes zoster ophthalmicus: a medical review.

Patients with herpes zoster undergo extensive screening to detect underlying malignant disease which is compromising their immunity. In a retrospective survey of 1000 patients with herpes zoster ophthalmicus 12 patients had malignant disease which was known on presentation. No new cases were detected or discovered on follow-up. Three patients developed a disseminated rash, but none of these had an underlying malignant disease.

Adolescent↗
PubMed1981

Plasma prolactin and gonadotrophins in anorexia nervosa and amenorrhoea due to weight loss.

The role of prolactin in anorexia nervosa is controversial and both hyperprolactinaemia and normoprolactinaemia were reported in patients with anorexia nervosa. We have measured immunoreactive prolactin by radioimmunoassay in plasma samples from 14 consecutive patients with anorexia nervosa and found normoprolactinaemia in 13 patients and a borderline elevation of plasma prolactin in one patient. The mean plasma prolactin level in anorexia nervosa patients did not differ from an age-matched control group of patients with amenorrhoea due to simple weight loss. While we were unable to confirm reports on the common occurrence of hyperprolactinaemia in anorexia nervosa, the absence of hyperprolactinaemia suggests a different mechanism of amenorrhoea in patients with anorexia nervosa and due to simple dieting from that in idiopathic secondary amenorrhoea in which the frequency of hyperprolactinaemia is about 30%. The mean plasma follicle-stimulating hormone was abnormally low both in patients with anorexia nervosa and simple weight loss, while the mean plasma luteinizing hormone was depressed only in patients with anorexia nervosa. This difference is compatible with a more profound hypothalamic disorder in anorexia nervosa, which is not solely dependent on the weight loss, than in amenorrhoea due to simple dieting.

Adolescent↗
PubMed1980

Ultrastructure and steroid-binding studies in leiomyomatosis peritonealis disseminata.

Leiomyomatosis peritonealis disseminata (LPD) is characterized by the development of numerous leiomyomata throughout the peritoneal cavity which appear grossly malignant but histologically benign. The etiology of this disorder has been controversial. The tenth reported case of LPD is presented with ultrastructural evidence that these tumors arise from smooth muscle cells. The cytoplasmic estrogen and progesterone bindings by these tumors were ninefold and twofold greater than receptor concentrations in normal myometrium from the same patient. In addition to the steroid binding data, the strong association of this disorder with pregnancy or, as in this case, oral contraceptives suggests that the stimulus for neoplastic initiation and growth is hormonally related.

Adult↗
PubMed1980

Substance P in human cord blood and its degradation by placenta in vitro.

Plasma immunoreactive substance P (iSP) was measured by radioimmunoassay in 12 paired samples of maternal and cord blood, and in placental extracts. The mean plasma iSP concentration in the cord vein was 42.5 pg/ml, as compared to 77.3 pg/ml in the maternal peripheral vein plasma. There was no difference in the mean iSP concentration in the cord vein and artery. Although no iSP was detected in placental tissue, the placenta could not be excluded as the source of iSP in cord blood in view of the rapid degradation of synthetic SP by the placental in vitro.

Female↗
PubMed1980

Is the evidence for ectopic antidiuretic hormone watertight?

The clinical syndrome of inappropriate secretion of antidiuretic hormone (SIADH) associated with malignancy cannot be distinguished from a similar metabolic abnormality found in patients with non-malignant conditions. It is, nevertheless, widely accepted that SIADH associated with malignancy is due to the "ectopic" tumour production of arginine vasopressin (AVP). This view is challenged after scrutiny of available data. Since some malignant or non-malignant tissues may produce neurophysins, the presence of "ectopic" AVP in tumour tissue may be explained by active binding of AVP from the circulation by neurophysins. On the other hand, the absence of detectable AVP in tumour accompanied with SIADH suggests excess AVP secretion from the posterior pituitary or hyponatraemia due to other, as yet unidentified, antidiuretic factors. The concept of "ectopic" AVP may be false.

Arginine Vasopressin↗
PubMed1980

Clinical course and outcome of thirty-five pregnancies in infertile hyperprolactinemic women.

Thirty-five pregnancies occurred during a 21-month follow-up period in 68 women (51%) who presented with infertility and hyperprolactinemia. Bromocriptine was used in 33 patients, of whom 25 (76%) conceived. In the remaining 35 patients who did not receive bromocriptine, there were 10 pregnancies (28%). The presence or absence of menses and galactorrhea in infertile hyperprolactinemic women treated with bromocriptine did not affect significantly the pregnancy rate. No pituitary complication occurred during pregnancy in any hyperprolactinemic patient and there was no change in sellar x-ray appearance, even in two patients whom a plain skull x-ray showed a minor sellar abnormality. Of the 35 pregnancies, 25 occurred after bromocriptine therapy, 2 after thyroxine therapy, 2 after clomiphene therapy, and 6 without any treatment. Five pregnancies ended in first-trimester abortion, including four after bromocriptine treatment. It is concluded that hyperprolactinemia is a good prognostic factor in infertility and that the majority of patients become fertile after a course of bromocriptine. No congenital abnormalities were observed in the offspring of patients treated with bromocriptine, but the abortion rate was higher than average.

Abortion, Spontaneous↗