Mass transfer limitations in gel beads containing growing immobilized cells.

Immobilized-cell aggregates have traditionally been approximated as effective continua within which the catalytic activity of the cells is homogeneously distributed. Chang & Park (1985), however, recently modelled the immobilized cells as discrete inclusions within a support matrix. With some modification, this theory is applicable to the analysis of microbial colonies growing within gel beads, and indicates that predictions obtained using the traditional approach may be significantly in error.

Combination treatment: colloidal bismuth subcitrate with H2-antagonists.

A formal single-blind multicentre study has been set up to investigate the probable benefit of combined therapy of the cytoprotective agent De-Nol (colloidal bismuth subcitrate, CBS) and an acid-suppressing drug (cimetidine) in the treatment of duodenal ulcer. The protocol compares the therapeutic benefit of CBS alone and cimetidine alone with CBS + cimetidine, the treatment period being 28 or 56 days. Patients whose ulcers heal within the therapeutic phase will be followed up until relapse or 12 months, whichever is the longer.

Controlled trial of Nd-YAG laser photocoagulation in bleeding peptic ulcers.

The efficacy of Nd-YAG laser photocoagulation in the endoscopic control of haemorrhage from peptic ulcers was shown in a controlled trial. 527 patients admitted consecutively with acute upper gastrointestinal haemorrhage underwent urgent endoscopy. Peptic ulcers were seen in 260.

Anxiety and endocrine changes in surgical patients.

There is a need for research to identify the relationship between psychological and endocrine responses to surgical operations, and to discover whether these responses differ with variations in practice between different settings. This preliminary study investigated 17 patients undergoing middle ear operations in two hospitals. Measurements included state anxiety, Recovery Inventory, cortisol excretion and noradrenaline excretion.

Endoscopic haemostasis of the upper gastrointestinal tract.

The realm of endoscopy has gone from that of diagnosis to that of diagnosis and therapy. Therapeutic endoscopy is a rapidly advancing frontier in the field of gastroenterology. Its use in securing haemostasis has recently flourished.

Nature of the bleeding vessel in recurrently bleeding gastric ulcers.

An unselected consecutive series of 826 patients admitted for acute upper gastrointestinal bleeding underwent urgent endoscopy. Peptic ulcers were found in 402 (49%). Of the 329 ulcer craters that could be fully examined, visible vessels were identified in 156 (47%), other stigmata of recent hemorrhage in 66, and no stigmata of recent hemorrhage in 107.

Spatial complexity and hand usage on the Block Design Test.

The Block Design test is a task utilizing spatial ability, on which subjects are required to arrange red and white blocks in a pattern similar to one presented on a stimulus card. 69 right-handed subjects were presented a series of trials which varied in difficulty or spatial complexity. The amount of time that each subject's hand was in contact with the blocks during each of the reproduction attempts was recorded.

Comparative inhibition of coffee-induced gastric acid secretion employing misoprostol and cimetidine.

Six healthy subjects (three men, three women) were studied to compare the effects of misoprostol and cimetidine on coffee-induced gastric secretion. Gastric secretion was measured after a 12-hr fast according to the Hobsley method, employing phenolsulfonphthalein (PSP) as a marker. Each subject was studied on three occasions separated by at least one week: as control, basal gastric secretion was measured followed by sample collection after oral placebo and then coffee; basal gastric secretion was measured followed by sample collection after 200 micrograms of misoprostol and then coffee; basal gastric secretion was measured followed by 300 mg [corrected] of cimetidine and then coffee.

Failure of gastroplasty pouch and stoma size to correlate with postoperative weight loss.

At the University of Alberta hospitals patients who underwent gastroplasty--horizontal, vertical with multistranded nylon banding of the stomas and vertical banded with Teflon reinforced stomas--have been followed up for over 2 years. Pouch volume ranged from 25 to 30 mL. Pouch volume and stoma size were measured radiologically 2 years after operation and correlated with the percentage excess weight loss.

Effects of propranolol on conditioned suppression, discriminated punishment and discriminated non-reward in the rat.

In Experiment I, two groups of rats were rewarded for lever-pressing under RI 64. During signalled 3-min intrusion periods shocks were delivered response-contingently (on RI 64) for the Punishment group and non-contingently (on RT 64) for the Conditioned Suppression group. d,l-Propranolol (2, 5 mg/kg) released intrusion responding to a similar extent in the two groups.

Endoscopic laser treatment of vascular anomalies of the upper gastrointestinal tract.

Vascular anomalies of the gastrointestinal tract are an important source of both acute and chronic blood loss. They present difficult management problems as they are often multiple, involving more than one part of the gastrointestinal tract, and may give rise to bleeds of increasing frequency and severity over a period of many years. We present the results of endoscopic argon and Nd YAG laser treatment of 18 patients with documented recurrent, severe haemorrhage from vascular lesions of the upper gastrointestinal tract with follow up of up to five years.

Technique for banding vertical gastroplasties.

The author describes a new technique for banding vertical gastroplasties, using polytetrafluoroethylene, in 177 patients. This material has several advantages over Marlex as a reinforcing material. It is inert, has no tendency to migrate and connective tissue invades its micropores holding it in place.

The effect of peripheral noradrenaline depletion on responding on a schedule of differential reinforcement of low rates of response (DRL).

First, it was confirmed that systemic injection of the neurotoxin 6-hydroxydopamine HBr (30 mg/kg IP) depleted noradrenaline levels in rat heart, but not centrally. Losses averaged 90% of control 1 day after injection, and 50% at 42 days. The same drug and dose was then administered to 50% of a group of rats which had been trained to lever-press for food reward on continuous reinforcement (CRF).

Comparison between the effects of propranolol and chlordiazepoxide on timing behaviour in the rat.

Ten rats were trained to lever press for food reward on a schedule of differential reinforcement of low rates of response with a 20-s criterion (DRL 20). Ten more were trained on a new schedule of punishment, designed to be comparable to DRL 20 - differential punishment of high rates of response (DPH 20). Under this schedule, responses with a latency of 20 s or more earned food rewards, while those of less than 20 s were followed by food reward and brief electric footshock.

Opposing acute and chronic behavioural effects of a beta-blocker, propranolol, in the rat.

Rats were trained over 40 days to lever-press for food reward under a schedule of differential reinforcement of low rates of response with a 20-s criterion (DRL 20), following seven sessions of continuous reinforcement. The effect of injecting a beta-adrenergic blocker, propranolol (5 mg/kg IP), before and at two different delays after each daily session of DRL were investigated. In Experiment I, rats drugged 5-8 min before every session earned fewer reinforcements compared to controls, and showed impaired temporal discrimination.

Which electrode? A comparison of four endoscopic methods of electrocoagulation in experimental bleeding ulcers.

Several inexpensive endoscopic methods of electrocoagulation have been advocated for treatment of gastrointestinal haemorrhage. We compared four types of electrode: dry monopolar - Cameron Miller (M), liquid monopolar - Storz (L), bipolar - Bicap ACMI (B), and heater probe - Seattle (H). The electrical and thermal properties of these probes were studied using computerised monitoring of energy deposition and their efficacy and safety was tested in a randomised study in 140 experimental canine gastric ulcers.

The psychologist's contribution to primary care: a reappraisal.

Developments over the past few years necessitate a reappraisal of the way in which clinical psychologists can best contribute to primary care. Up until now, psychologists have concentrated on those problems which are their concern within psychiatric hospitals. In addition, they have largely adopted a specialist model of service which may not be in the best interests either of primary care or of clinical psychology.