A technique for the laboratory evaluation of the speed of onset of I.V. anaesthesia

A method is described for the evaluation of the speed of onset of i.v. anaesthesia in mice. The technique involves (a) determination of the median hypnotic dose (HD50) by plotting the probit value of the percentage of mice sleeping, against dose on a logarithmic scale, (b) plotting mean induction time over a range of doses against the logarithm of the dose and (c) comparison of induction times at 1.25 HD50. All doses were given over 1 s or 10 s. A 1-s injection was thought to be of most value in the evaluation of structure activity effects whereas the 10-s injection produced results similar to those which have been reported in man. With this technique, and using 1-s injection times, induction times were found to be similar with thiopentone and Althesin. Those following methohexitone, etomidate and propanidid were marginally longer whereas ketamine and pentobarbitone were obviously slower in onset.     

Ovine cysticercosis in the Albany region of Western Australia. 1. Survey of tapeworms of rural dogs

A survey of the cestode infections of 304 dogs from 134 properties in the Albany area of Western Australia was performed. Purgation was induced by oral administration of arecoline and the purge examined for cestodes. The cestodes found and their infection rates were: Dipylidium caninum 16.4%; Taenia spp 36.5%; T. ovis 8.9%; T. hydatigena 15.1%; T. pisiformis 15.1%; T. serialis 2.3%; Echinococcus granulosus 0.7%; Questionnaires completed on 133 of the 134 properties at the time the dogs were purged showed that:--73.6% of farmers were feeding raw sheep-meat and 24.8% were feeding raw offal to their dogs; dogs were treated on a regular basis with a cestocide on 23.3% of properties; dogs were allowed to roam on 21.8% of the properties and stray dogs were considered prevalent on 23.3% of properties. Suggestions for control of Cysticercus ovis are made based on an interpretation of the significance of these findings.     

Physical attractiveness, physical effectiveness, and self-concept in late adolescents

The differential role of various body attitudes in predicting the self-concepts of late adolescents (124 males and 218 females), enrolled in introductory psychology courses, was assessed. Subjects rated 24 body characteristics in terms of 1) how physically attractive they assumed these parts of their bodies were, and 2) how physically effective they assumed them to be; subjects also responded to a short self-concept scale. In accordance with the theory of Erikson (1968) and of McCandless (1970), it was expected that attractiveness attitudes should contribute more to the self-concepts of females than should effectiveness attitudes, while a reverse pattern of interrelatedness was expected for males. Results indicated a higher correspondence between what are seen as attractive body parts and what are viewed as effective body components for males than for females. Moreover, findings from step-wise multiple regression analyses of each sex group's ratings of the body parts for attractiveness and effectiveness, respectively, each with the criterion variable constituting mean self-concept score, were consistent with expectations. For females, the multiple correlation between attractiveness ratings and self-concept was greater than the multiple correlation between effectiveness ratings and self-concept, and more attractiveness variables than effectiveness variables were significant predictors of self-concept. The converse of these findings were obtained with the males' data. The relevance of these results for theories of personality development were discussed.     

Heterogeneity of plasma glucagon. Circulating components in normal subjects and patients with chronic renal failure

Plasma immunoreactive glucagon (IRG) concentrations were measured in 36 patients with chronic renal failure (CRF) and 32 normal subjects. In addition, the components of circulating IRG were analyzed by gel filtration in the fasting state and after physiological stimuli. Fasting IRG was elevated (P less than 0.001) in CRF patients (534 +/- 32 pg/ml) compared with the levels found in healthy subjects (113 +/- 9 pg/ml). Oral glucose suppressed plasma IRG in CRF patients from a basal level of 568 +/- 52 to a nadir of 354 +/- 57 pg/ml (120 min). This degree of suppression (38%) was comparable to that found in normal subjects (basal = 154 +/- 20 to 100 +/- 23 pg/ml) at 120 min (35%). Intravenous infusion of arginine (250 mg/kg) resulted in a 71% rise in IRG in CRF patients and a 166% increase in normal subjects. Gel filtration of fasting plasma from CRF patients showed three major peaks. The earliest (A) was found in the void volume (mol wt greater than 40,000) and constituted 16.5 +/- 4.7% of the elution profile. The middle peak (B) eluted just beyond the proinsulin marker (approximately 9,000 mol wt) and constituted the largest proportion of the elution profile (56.5 +/- 3.4%). The third peak (C) coincided with the standard glucagon and [125I]glucagon markers (3,485 mol wt) and comprised 27.0 +/- 4% of the IRG profile. In contrast, only peaks A and C were found in fasting plasma of normal subjects (53.6 +/- 10.4% in A and 46.4 +/- 10.4 in C). After oral glucose, glucagon immunoreactivity in the 3,500 mol wt peak (C) was markedly suppressed, while the B peak in patients with CRF declined to a lesser extent. The A peak in both groups was unchanged. After an arginine infusion only the C peak increased in both groups of subjects. Gel filtration of plasma in 3 M acetic acid gave similar profiles to those obtained in glycine albumin buffer. Exposure of serum to trypsin indicated that the B and C peaks were digestible, while the A peak was resistant to the action of the enzyme. In one sample, peak C increased after a 2-h exposure of serum to trypsin. We conclude that circulating IRG in normal subjects and patients with CRF is heterogenous. The hyperglucagonemia of renal failure is largely due to an increase in IRG material of approximately 9,000 mol wt, consistent with proglucagon, although the 3,500 mol wt component is also considerably elevated (threefold). The significance of circulating IRG levels should be interpreted with caution until the relative biological activity of the three components is established.     

Delegation

The three basic elements of delegation (responsibility, authority and accountability) are discussed with regard to effective management. Major guidelines for effective delegation are noted, including: (1) securing a mutual commitment to responsibilities involved; (2) establishing goals and checkpoints; (3) giving appropriate authority to the delegate; and (4) avoiding by-passing the delegate.