The acute abdomen following cardiopulmonary bypass surgery

Over a 5-year period, 9 patients (0.85 per cent) developed a major acute abdominal complication after cardiopulmonary bypass surgery. Difficulties in the initial recognition and diagnosis of these complications in sedated, ill patients are highlighted. A high index of suspicion is important in the early diagnosis of these complications. The numbers are too small for statistical analysis, but experience suggests that each case should be dealt with on its merits in accordance with common surgical practice and that operative management should not be rejected because the patient has recently undergone a major cardiac operation.     

Type A coronary-prone behavior in the work environment

The model presented in this paper accounts for the relationship between Type A behavior and the work environment and identifies: (1) susceptible Type A individuals; (2) potential occupational stressors in the work environment; (3) subsequent resulting control conflict and maladaptive coping behavior; (4) feedback error and time lag resulting in detrimental symptoms; and (5) methods of changing Type A behavior (Fig 1). From this literature review, it becomes clear that there is a need for further prospective research especially in the area aimed at isolating and determining the specific work environment variables which enhance Type A behavior. As yet, no prospective research project is known which has followed a sample of employees from their job application and interview situation through their careers, in order to investigate changes in, and influences on, Type A behavior patterns. Finally, there is an obvious need for the introduction of more Type A behavior modification programs for workers, and perhaps more emphasis should also be directed toward changing the Type A behavior pattern socialization process, which appears to be so prevalent in urban, middle-class home environments.     

Composite sampling

In sampling certain types of materials, such as bags of fertilizer, or subsampling large quantities of water, as might be done in investigating the density of plankton in certain environmental situations, it is customary to composite the samples. That is, several samples are drawn, mixed into a composite sample, and a sample taken from the composite is then used to determine relevant characteristics of the population. In this paper the results of Brown and Fisher [1972] are extended to more complex situations (e.g., more than one variance component present).     

Erythrocyte basophilic stippling in the Mongolian gerbil

Basophilic stippling of the circulating erythrocytes is characteristic of the Mongolian gerbil. Its enzymatic digestion along with the concomitant removal of diffuse erythrocytic polychromasia by the action of ribonuclease demonstrates that it represents microscopically visible aggregates of cytoplasmic ribonucleoprotein, presumably of ribosomal origin. Up to 40% of the total circulating erythrocytes may be stippled in foetal and newborn animals. There is then a progressive decline in incidence until adult levels are attained at least by 20 weeks of age. The bone marrow of the adult gerbil contains a higher proportion of stippled red cells than the circulating blood. The stippling can be either coarse or fine and observable in both polychromatophilic and orthochromic cells. It is suggested that erythrocytes with basophilic stippling are relatively immature red cells still demonstrating remnants of cytoplasmic ribonucleoprotein.     

Erratum: Dimensionality of subjective response to a selection of complex aversive stimuli.

Reports an error in "Dimensionality of subjective response to a selection of complex aversive stimuli" by Richard W. Neufeld and Park O. Davidson (Canadian Journal of Behavioural Science Revue canadienne des Sciences du comportement, 1974[Jul], Vol 6[3], 258-269). An error was made in the printing of Figure 1 (page 261). The correct Figure is provided in this erratum. (The following abstract of the original article appeared in record 1975-00428-001.) Investigated the dimensionality of subjective responses to a variety of stressor stimuli using a multidimensional scaling procedure with 30 undergraduates as Ss. Results indicate that the subjective perception of these stimuli was multidimensionally determined but with only 1 inter-S viewpoint about the obtained dimensionality. Stimulus projections on 2 dimensions were significantly correlated with scaled values of a unidimensional stress scale and were found not to be independent of a subjective attention scale. Speculations about the nature of the obtained dimensional structure, along with possible implications for assessing mechanisms of coping with stress, are discussed briefly. (French summary) (41 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Influence of the number of questions on the student''s achievement in tests of anatomy

The authors compare student's achievement in tests with low and moderately high number of questions requiring short answers. Five groups of Medical School students underwent their regular Anatomy evaluation tests, which consisted of 13 questions (one group), 15 (two groups) and 25 (two groups). In each group five questions were chosen at random, average scores being calculated from their marks. These scores were statistically compared to the ones calculated from the marks given to the full-length evaluation tests; it became quite evidente that averages go up when the number of questions is increased. Putting the averages in terms of A, B, C and D scores (very good, good, regular and insufficient), it was noted that failure to reach at least the C score is inversely proportional to the number of questions. The results are discussed in terms of determining the most proper number of questions to be given in a test.     

Liposomes disposition in vivo. V. Liposome stability in plasma and implications for drug carrier function

The kinetics of [14C]sucrose release from multilamellar liposomes of fixed diameter (approx. 0.23 micron) incubated in human plasma (serum and blood) were quantified. Composition was various ratios of phosphatidylcholine, phosphatidic acid and cholesterol with alpha-tocopherol included as antioxidant. Considerable intra-individual variability was noted for liposome stability in blood and its derived fluids, yet reproducible results were obtained for pooled samples. The destabilizing effects of plasma decreased with increasing lipid concentrations. Results of fitting a kinetic model to the data showed that four of five model parameters were linearly related to liposome cholesterol content. Liposomes depleted plasma of its destabilizing factors, and when pre-incubated with plasma were partially stabilized to the effects of a subsequent plasma addition. Plasma caused a rapid rise in liposome membrane permeability which then declined non-linearly, presumably because of a rearrangement of membrane lipids and adsorbed proteins to form their most stable configuration. The therapeutic availability of drugs administered encapsulated in liposomes, which can be governed by the kinetics of their in vivo extracellular release, may be directly proportional to--and predictable from--the time-course and extent of release in plasma. The kinetic model was used in conjunction with simple pharmacokinetic assumptions to show that the effectiveness of a liposome drug carrier cannot be predicted based simply on its plasma stability; more stable liposomes may not be more effective drug carriers. Interestingly, plasma-induced solute release from liposomes serendipitously mimics an important facet of ideal carrier behavior.     

Comparison of the quasifree charge-exchange reaction for 12C and 54Fe

Serotonin (5-hydroxytryptamine, 5-HT) in blood is stored in platelets and has vascular and platelet stimulating effects when released into plasma. Accurate measurements of 5-HT in plasma are complicated by inadvertent platelet activation causing sampling artifacts and by analytical problems when determining trace levels. We developed an assay for plasma 5-HT based on solid-phase extraction (Sep-Pak C18), aqueous acetylation, pentafluoropropionylation, and negative ion chemical ionization gas chromatography-mass spectrometry. The method was able to recover 5-HT from plasma by > 90% and to quantitate with a precision of 7.5% at a level of 0.5 nmol/l. It was used to define blood sampling and sample handling procedures giving low and consistent values for 5-HT. A good blood sampling technique, adequate platelet stabilization in the test tube, and rapid high speed centrifugation of the blood resulted in low plasma levels of both 5-HT and beta-thromboglobulin (a platelet release product). Using these procedures plasma 5-HT levels in healthy volunteers were found to be 0.77 +/- 0.38 (mean +/- S.D.; range 0.27-1.49) nmol/l (n = 18), which is 4-100-fold lower than previously reported values.