Search PubMed⌕ Search

Biomedical subjects

C G Clark

Publications and source records attributed to C G Clark.

At least 163 records · Page 9Linked to original sources
PubMed1978

Natural history and prognosis of recurrent breast cancer.

Patterns of recurrent disease were analysed in 603 patients with breast cancer. The time of onset, frequency of recurrence, and survival after recurrence were not influenced by age or menopausal state. While survival after local recurrence was longer than survival after distant metastasis, the time to onset of local and distant disease followed an identical pattern, indicating that local recurrence should be regarded as a manifestation of systemic disease. Postoperative radiotherapy did not affect the time of onset of local recurrence. We suggest that patients with local recurrence should receive both systemic and local treatment and that controlled trials of chemotherapeutic agents in these patients might be valuable in finding the most effective drug combinations to be used as adjuvant treatment after mastectomy.

Adult↗
PubMed1977

In vitro effects of gastrin on the movement of electrolytes across the human colon.

Using an in vitro system, the effect of gastrin on the colonic handling of water and electrolytes has been investigated. Gastrin converted the normal mucosal absorption of water and sodium into a net secretion. The colonic response to gastrin was done-related with respect to sodium, and the effects were greater when it was added to the serosal side. The potassium handling of the isolated colonic mucosa was not altered by gastrin. At a concentration of 800pg/ml, gastrin signficantly reduced the normal movement of sodium from mucosa to serosa (absorption) but significantly increased serosal to mucosal movement (secretion). This alteration in the bidirectional flux of ions under the influence of gastrin may be clinically important and could account in partt for the diarrhoea associated with the Zollinger-Ellison syndrome.

Body Water↗
PubMed1977

Drugs for peptic ulcer.

Conservative management of peptic ulcer relies on the use of drugs as an adjuvant to the time-honored measures of avoiding stress, reducing gastric secretion, and regulating the diet. Alkalies neutralize acid and anticholinergic drugs partly inhibit secretion.. Both are widely used but are often inadequate to control symptoms. Carbenoxolone appears to have a more specific effect in promoting healing of gastric ulcers and has now been used for 15 years. Its role in the treatment of gastric ulcer can be critrically examined, particularly in relation to how this influences surgical management. Recently introduced compounds know as histamine H2-receptor antagonists have a profound effect in inhibiting gastric secretion. Early experience in patients with duodenal ulcer indicated the efficacy of these compounds in promoting healing. These potent new drugs are likely to influence strongly the management of patients with duodenal ulcer, and this may affect the indications for surgery.

Animals↗
PubMed1976

Some observations on gallstones and bile composition.

A series of 31 consecutive patients undergoing surgery for gallstone disease has been studied and the composition of the gallstones and bile from the gallbladder and common duct determined. As a result of the stone analysis by the X-ray powder diffraction method, the patients were classified according to whether their stones consisted of cholesterol, calcium salts or a mixture of the two. The mean composition of the common duct bile for the groups with cholesterol and mixed stones was just outside the micellar region of cholesterol solubility. The gallbladder bile from the cholesterol group of stone-formers was also supersaturated, but the gallblader bile from the group of mixed stone-formers was undersaturated with respect to cholesterol. None of the patients forming gallstones of calcium salts showed any abnormality in the cholesterol content of their bile.

Bile↗
PubMed1976

The possibility of dietary protective factors in duodenal ulcer. II. An investigation into the effect of pre-feeding with different diets and of instillation of foodstuffs into the stomach on the incidence of ulcers in pylorus-ligated rats.

Rats pre-fed on a South Indian diet show a much higher incidence of ulceration of the stomach after pyloric ligation than those on a North Indian diet. Removing vegetables and pulses from the North Indian diet deprives it of its protective effect. Staple foodstuffs with a high buffer content (unmilled rice, unrefined wheat and a millet [ragi]) placed in the stomach after pyloric ligation are also protective, but those with a low buffer content (milled rice, tapioca, sorghum and maize) are not protective. Refined wheat, however, gives protection despite its low buffer content. The significance of these findings in relationship to the distribution of duodenal ulcer in India and Africa is discussed.

Animals↗
PubMed1976

Clinical experience with metiamide.

The new histamine H2-receptor antagonist, metiamide, was shown to inhibit acid and pepsin secretion in gastric secretion studies performed on patients suffering from peptic ulceration. The new drug was administered intravenously in these experiments, but effective plasma levels could also be produced by oral administration. When symptomatic patients were treated with the drug nearly all experienced marked symptomatic relief, and there was some evidence that ulcer healing occurred during treatment. When the drug was withdrawn symptoms tended to return. No toxic reactions were encountered in this trial. Double-blind studies are now being made in Britain to establish the place metiamide may have in the treatment of duodenal ulceration.

Depression, Chemical↗
PubMed1975

Gallbladder function, cholesterol stones, and bile composition.

Gallbladder bile obtained at operation from five patients with no symptoms of biliary disease was undersaturated with cholesterol in every case. However, gallbladder bile from patients with stones composed of 97-100% crystalline cholesterol was on average just saturated with cholesterol when the gallbladder was functioning and undersaturated when it was not. Regardless of gallbladder function, the patients with stones had on average significantly more cholesterol in their bile than in the control group, but the differences between the mean composition of bile from functioning and non-functioning gallbladders were not significant. Common duct bile from patients with non-functioning and functioning gallbladders was on average supersaturated with cholesterol, but there was significantly more bile salt and significantly less cholesterol in the bile from patients with non-functioning gallbladders. Only in the case of patients with functioning gallbladders did the mean composition of the common duct and gallbladder biles differ significantly. The former contained significantly more cholesterol and less bile salt than the latter. It is suggested that patients with non-functioning gallbladders may be 'autocholecystectomised' with the duct bile reverting to a more 'normal' composition.

Bile↗