Search PubMed⌕ Search

Biomedical subjects

D Campbell

Publications and source records attributed to D Campbell.

At least 307 records · Page 17Linked to original sources
PubMed1984

A pioneer synthesis of conjugates of a thymic peptide hormone and polyamines.

To synthesize peptidic derivatives of polyamines, sequential reactions were designed for the polyfunctional peptides and polyfunctional amines which utilize specific protection and deprotection. Utilizing these reactions, a thymic nonapeptide, a lymphocyte-differentiating hormone, was coupled with spermidine and spermine to yield, respectively: Glp-Ala-Lys-Ser-Gln-Gly-Gly-Ser-Asn-NH(CH2)3NH(CH2)4NH2; Glp-Ala-Lys-Ser-Gln-Gly-Gly-Ser-Asn-NH(CH2)3NH-(CH2)4NH(CH2) 3NH2. Both conjugates inhibited rather than stimulated incorporation of [3H]-thymidine into DNA at levels 20-fold that of spermine. This activity is less than that based on the percent of the spermine moeity (ca. 20%) in the conjugate.

Animals↗
PubMed1984

The effect of very prolonged membrane rupture on fetal development.

This retrospective study examined the effects of very prolonged membrane rupture of more than 1 week on the development of pulmonary hypoplasia and positional deformities in the infants of 100 consecutive women. A control group of infants who were matched for gestational age at delivery, sex, and time of delivery was identified. The results indicate that there was a statistically significant difference (p less than 0.001) in the occurrence of pulmonary hypoplasia and positional deformities. The greatest impact of prolonged membrane rupture on fetal development was seen in the patients in whom membrane rupture occurred prior to 26 weeks' gestation and the duration of rupture was more than 5 weeks.

Bone and Bones↗
PubMed1984

Winter breaks.

Explore the source record for details and available documents.

Athletic Injuries↗
PubMed1984

A components analysis of biofeedback in the treatment of fecal incontinence.

Fecal incontinence is a socially disabling symptom for which rectosphincteric biofeedback has been reported to be dramatically effective. The most commonly employed biofeedback procedure incorporates three separate and potentially effective components: exercise of the external sphincter muscle, training in discrimination of rectal sensations, and training synchrony of the internal and external sphincter responses. This paper reports the results of single case experiments employed with eight incontinent patients to examine the contributions of each of these components. All eight patients improved, but only one required the biofeedback procedure as it was originally described. Three responded to sensory discrimination training, one to exercise training, and one to the training of synchronous sphincteric responses; three recovered independently of the effects of biofeedback. Despite the achievement of continence, the rectosphincteric reflexes following treatment continued to be abnormal in every case. These findings suggest that the character of the external sphincter response to rectal distension is an unreliable index of sphincter function and that exercise and sensory discrimination training procedures are effective for some cases of fecal incontinence.

Adolescent↗
PubMed1984

A one-year multicenter clinical trial of pilocarpine gel.

In a one-year clinical trial of pilocarpine gel, a form designed for once-a-day administration, in 83 patients with glaucoma, average intraocular pressures during gel therapy were equal to or slightly lower than previous values during pilocarpine eyedrop therapy (morning values, 18.7 mm Hg vs 19.7 mm Hg; afternoon values, 20.9 mm Hg vs 20.2 mm Hg). Monitoring of diurnal intraocular pressure showed that 33 of 77 patients (43%) using the gel and 25 of 77 (33%) using eyedrops had afternoon values more than 2 mm Hg higher than their morning values. This difference was not statistically significant. Fifteen of 76 patients (20%) who used the gel for more than eight weeks developed a diffuse superficial corneal haze with gel treatment. The haze persisted 12 months after the gel was discontinued. Although the haze produced no symptoms, its long-term consequences are unknown.

Adult↗
PubMed1984

Effects of sodium bicarbonate and 1,25-dihydroxy-cholecalciferol on calcium and phosphorus balances in the rat.

Metabolic balance studies were undertaken to determine whether sodium bicarbonate (NaHCO3) supplements (4.5 mmol/day) altered 7-day cumulative calcium (Ca) phosphorus (P) balances in growing rats consuming either a basal diet providing 0.6% Ca and 0.3% P, or this diet plus 1,25-dihydroxycholecalciferol [40 ng 1,25(OH)2D3/day]. Feeding bicarbonate lowered urinary Ca but raised fecal Ca so that Ca balance became less positive. However, 1,25(OH)2D3 increased net absorption of Ca and P to the same degree when given to control rats and rats consuming bicarbonate. Nevertheless, bicarbonate-fed rats had lower net Ca absorption than controls, even when treated with high doses of 1,25(OH)2D3. Changes in net Ca absorption induced by bicarbonate may occur at a point in the gut distal to the duodenum since duodenal 45Ca absorption was decreased by bicarbonate feeding. The present results show that bicarbonate consumption depressed net Ca absorption in the rat. The effect appears to be independent of changes in 1,25(OH)2D3 metabolism because it is manifest in animals receiving high doses of 1,25(OH)2D3, which stimulate alimentary Ca absorption maximally, and because bicarbonate-fed rats are able to respond normally to exogenous 1,25(OH)2D3 by increasing their net absorption of Ca and P. In view of this demonstration that NaHCO3 supplements elevate fecal Ca loss in the rat, it is suggested that studies should be undertaken to determine whether bicarbonate exerts similar adverse effects on Ca balance in humans.

Absorption↗
PubMed1984

Constant intrarenal infusion of PGE1 into a canine renal transplant using a totally implantable pump.

A method was devised whereby PGE1 could be administered to a canine renal transplant recipient on a chronic basis. PGE1 was stored in the reservoir of an implantable pump and delivered continuously in high doses directly into the renal transplant artery. In the model studied a contralateral untreated transplant from the same donor served as a control. Sequential renal scans were used to study the effect of intraarterial PGE1 on the rejection process. Continuous delivery of PGE1 into the renal transplant artery did not prevent allograft failure under these conditions; blood flow diminished similarly in both PGE1-treated and untreated transplants. There were, however, striking differences in the histologic appearance of treated and untreated transplants. PGE1 perfusion resulted in the appearance of large numbers of polymorphonuclear leukocytes but few lymphocytes. In the untreated control allograft, however, the findings were typical of lymphocyte-mediated acute rejection. The distinctive differences noted histologically suggested that the local administration of PGE1 influenced the mechanism by which graft failure occurred. The ability to manipulate cell populations infiltrating an allograft represents a potentially important means for modifying the immune response.

Alprostadil↗
PubMed1984

Five-year double-blind fluoridated milk study in Scotland.

A 5-yr double-blind fluoridated milk study has been completed and, following baseline stratification, 94 children aged 4 1/2/5 1/2 yr were allocated to the test group and 93 to the control. Each subject received 200 ml school milk daily, identification between the test and control plastic packs being by colour-coding alone with the former containing 1.5 mgF- giving a potential topical benefit of approximately 7 ppmF- per school day. After 5 yr, 50 of the test children remained and 56 of the controls. While the mean DMFT incremental data relating to permanent teeth was always in favour of the test group, it was not until the fourth year that a significant difference was obtained (P less than 0.01) between the fluoridated group (mean, 1.65) and the non-fluoridated group (mean, 2.56). For permanent teeth which were unerupted at baseline, the mean DMFS differences increased to 39.6% at the same time and to 48.0% by the fifth year. No benefit was noted for previously erupted primary teeth. Cavitation was less in the test group throughout the study. When the third, fourth and fifth year DMFT reductions obtained were compared with previously published artificial water fluoridated data where children were of comparable age at the onset of water adjustment, similar caries inhibition data were noted.

Animals↗
PubMed1984

Operation for discrete subvalvular aortic stenosis.

Over the past 20 years, 37 patients (31 children and six adults) have undergone operations for discrete subvalvular aortic stenosis. Prior to 1975, resection of the subvalvular membrane alone was the procedure of choice. However, the recurrence rate was high (36%). Since 1975, resection of the membrane plus left ventricular myectomy has been routine. The recurrence rate in this group has been lower (20%) but is still high. Overall, 11 patients (30%) have had significant recurrence (average gradient 63 mm Hg). Eight of these 11 have undergone a second operation with re-resection of a membrane and left ventricular myectomy. One patient died and in three others (42%) significant symptoms and gradients remained. One of these three has undergone a successful aortoventriculoplasty, and two patients are awaiting a similar operation. Lessons learned from this experience include the following: (1) Regardless of the type of initial operation, a significant rate of recurrence can be anticipated. (2) Progressive aortic insufficiency and fibromuscular tunnel stenosis occur commonly unless adequate relief of the obstruction is achieved by the first operation. (3) Because repeat resection with left ventricular myectomy is unlikely to be effective when aortic insufficiency and/or tunnel stenosis are present, aortoventriculoplasty should be employed as the definitive reoperative procedure.

Adolescent↗