Measurement of the steady-state shear characteristics of filamentous suspensions using turbine, vane, and helical impellers.

The impeller viscometer technique is frequently used to characterize the rheology of filamentous suspensions in order to avoid difficulties encountered with conventional instruments. This work presents the results of experiments conducted with vane, turbine, and helical impellers. The validity of the assumptions made in the determination of the torque and shear-rate constants were assessed for each impeller type. For the turbine and vane impellers, an increase in the apparent torque constant c was observed with increasing Reynolds number even when measurements were confined to the viscous regime. The shear-rate constants determined for the vane and turbine impellers varied for different calibration fluids, which contradicts the assumptions usually invoked in the analysis of data for this technique. When the helical impeller was calibrated, consistent values for the torque and shear-rate constants were obtained. The three impeller types were also used to characterize the rheology of cellulose fiber suspensions and the results compared for consistency and reproducibility. The results have application in design of rheometers for use in process control and product quality assessment in the fermentation and pulp and paper industries.

Interhospital transfer of the critically ill trauma patient: the potential role of a specialist transport team in a trauma system.

A specialist transfer team based in the regional intensive therapy unit (ITU) at the Western Infirmary, Glasgow, acts as a central interhospital retrieval team for Glasgow and the west of Scotland. The establishment of trauma systems has been proposed. This paper describes the activities of the specialist transfer team to illustrate the potential role of a central retrieval team within such a system.

An assessment of portable carbon dioxide monitors during interhospital transfer.

Four portable carbon dioxide monitors were assessed by a mobile intensive therapy team during interhospital transfer of critically ill patients. Particular attention was paid to practical considerations such as size, battery life and ease of use. All the monitors performed well in terms of accuracy but problems with size and battery life made some less suitable for use outside hospital.

Transfer of the critically ill obstetric patient: experience of a specialist team and guidelines for the non-specialist.

Transfer of the critically ill obstetric patient between hospitals is increasingly common. The specialist transfer team based at the Western Infirmary Intensive Therapy Unit, Glasgow has transported 60 such patients in the years 1985-1994. Monitoring was by direct arterial pressure measurement in 56 patients and central venous pressure measurement in 45. Forty-one patients were mechanically ventilated in transit. There were no deaths in transit but 3 patients died later in intensive care. The majority of patients had pregnancy induced hypertension or had suffered a post partum haemorrhage. A clinical impression that these two groups had different treatment requirements and outcomes was not substantiated. We conclude that the transfer of even the sickest obstetric patient is feasible and safe and suggest guidelines to non-specialists for the management of these patients before and during interhospital transfer.

Heparin is not metabolized by the perfused rat liver.

The role of the liver in metabolism of heparin was studied using the isolated rat liver perfused in vitro for 10 hr. Porcine intestinal heparin (1000 u) was added to the recirculating liver perfusate, and serial heparin measurements were performed on the liver perfusate every 2 hr, as well as on bile samples secreted by the perfused liver. Heparin concentration remained at a constant level throughout the 10 hr of perfusion, and there was no detectable heparin secreted into bile samples. The findings suggest that hepatic metabolism/clearance plays a minimal role in heparin kinetics in plasma.

The potential for the introduction of the marketing concept into Australian public hospitals.

Marketing theory and practice has gained broad acceptance in the business world generally. Of recent years, particularly in the United States, there have been increasing moves to incorporate marketing activities into the management of hospitals. In Australia there appears little empirical evidence in the literature to suggest a similar progression. This paper seeks to examine some of the essential ideas contained within the marketing concept and to expose the applicability of marketing to the efficient management of public hospitals.

Plastic-embedded human marrow biopsy specimens: improved histochemical methods.

Improved methods for processing, sectioning, and staining plastic (glycol methacrylate)-embedded human marrow biopsy specimens were studied. Special stains, including naphthol AS-D-chloro-acetate esterase, PAS, reticulin, and iron, have been modified so that they are suitable for undecalcified, 2-microns-thick, plastic-embedded human marrow biopsy specimens. These adaptations permit plastic-embedded marrow specimens to be used for clinical diagnosis. Marrow biopsy specimens embedded in plastic were compared with biopsy specimens preserved by the conventional paraffin method. The plastic-embedded marrows provide better results from morphologic examination (enhancing diagnostic accuracy), permit assessment of bone as well as of marrow, and allow histochemical analysis to be performed.

Malignant adenolymphoma.

Adenolymphoma (Warthin's tumor) is a well studied benign tumor of the salivary gland. Malignant transformation of such a tumor is rare and not well documented in the literature. The light microscopic and ultrastructural features of an undifferentiated carcinoma arising in an adenolymphoma in the parotid gland of a middle aged male are described, and the relevant literature is reviewed. Similarities between the benign adenolymphoma and the undifferentiated malignant tumor, such as the presence of interstitial lymphoplasmacytic cell infiltrates, dark and light epithelial cells, similar cytoplasmic organelles, and nuclear morphology, suggest a malignant transformation of a previously existing benign adenolymphoma.