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Biomedical subjects

M Ross

Publications and source records attributed to M Ross.

At least 235 records · Page 13Linked to original sources
PubMed1989

Women's theories of menstruation and biases in recall of menstrual symptoms.

Previous research is consistent with the proposition that people use implicit theories of personal stability or change in remembering the attributes they possessed in the past. However, there has been little systematic investigation of the relation between these implicit theories and memory biases. In this study, the relation between women's theories of menstrual distress and their recollections of physical and affective symptoms was examined. Ss completed daily questionnaires in which they evaluated themselves on several physical and affective symptoms. Later, some Ss were asked to recall the ratings they had made on a day when they were menstruating; others recalled a day when they were not menstruating. At the time of recall, all Ss were in the intermenstrual phase. Finally, Ss completed a measure designed to assess their theories of how they are typically affected by menstruation. The recollections of Ss who recalled the menstrual state were biased so as to be consistent with their theories of menstrual distress: The more a woman believed in the phenomenon of menstrual distress, the more she exaggerated, in recall, the negativity of her symptoms during her last period. The recollections of women asked to recall the intermenstrual state were unrelated to their theories of menstruation. Furthermore, consistent with previous research, the daily questionnaire ratings revealed that physical symptoms varied with menstrual cycle phase, whereas affective symptoms did not. Finally, comparisons between subjects' theories and daily ratings revealed that, on average, women exaggerate the degree to which they experience changes during menstruation.

Adaptation, Psychological↗
PubMed1989

Blinking and corneal sensitivity.

We have investigated the relationship between corneal sensitivity and blinking patterns. Using a group of 9 young normal subjects, measurements were made of blink patterns, central and peripheral corneal sensitivity and lid margin sensitivity both before and after use of topical corneal anaesthetic, proxymetacaine hydrochloride (Alcaine). Blink patterns were recorded through concealed filming and were later analysed in terms of blink frequency and the type of blinks (proportion of complete, incomplete, twitch and forced blinks). Blink rate was significantly lower following anaesthetic administration, but the relative proportion of blink types remained unchanged. We speculate that one of the factors responsible for normal involuntary blinks is the imminent break-up of the tear film which is sensed by the cornea.

Adult↗
PubMed1989

The use of distilled water as an irrigating fluid in patients undergoing transurethral resection of the prostate.

Thirty patients undergoing transurethral resection of the prostate using distilled water as an irrigating fluid were studied. There was no significant change in the serum concentration of the variables studied (preoperatively compared to postoperatively) as possible indicators of haemolysis or absorption of irrigating water such as sodium, potassium, albumin, total protein, creatinine, uric acid, urea, haemoglobin, haematocrit and haptoglobin. The mean value of plasma haemoglobin (P-Hb), observed immediately postoperatively and reflecting the magnitude of haemolysis, was delta 294.8 mg/l. There was a good correlation between P-Hb and the inflowing irrigating distilled water (r = 0.69). The P-Hb variation (delta) correlated with resection time and with the weight of the resected prostate (r = 0.54 and r = 0.52, respectively). A good correlation was also found between resection time and delta body weight which reflects the amount of water absorbed (r = 0.67) and between delta body weight and the inflowing irrigating water (r = 0.61). Our study shows that distilled water can be used as an irrigating fluid quite safely. The advantages of distilled water outweigh the disadvantages which can be avoided easily if proper attention is given.

Absorption↗
PubMed1989

[Silent myocardial ischemia. The practice of sports in coronary patients].

In 1988 we retrained for exercise 800 coronary patients who had suffered a myocardial infarction or had benefited from revascularization surgery. Twenty per cent of these patients under anti-anginal treatment have silent myocardial ischaemia (SMI). Four per cent still have exercise-induced angina. The influence of SMI on the prognosis, frequently through an acute coronary accident or through the slow development of an ischaemic cardiomyopathy, has prompted us to determine a heart rate that should not be exceeded by coronary patients while practising sports. We learned by experience that coronary subjects with SMI should not practise sports immediately they get up; they should proceed gradually and always after a mandatory warming up period. Outdoor activities in periods of severe cold or strong winds should be banned and replaced by indoor games which should take place outside the digestion period. Finally, all concepts of competition, endurance or performance should be excluded from their practice of sports. The finding that two out of three coronary patients underestimate their rate by 20% should, in the absence of atrial or thoracic capillary feelers, lead to the conclusion that the heart rate not to be exceeded must be underestimated by 20%.

Coronary Disease↗
PubMed1989

[Duodenal obstruction caused by cholelithiasis (Bouverets' syndrome): a clinical case].

A 55 year old man presented with vomiting, abdominal pain, diarrhea, jaundice and choluria. An obstruction of the gastric outlet by a large gallstone located at the duodenum was demonstrated by radiologic, ultrasonographic and endoscopic examinations. The stone could not be removed through endoscopy and the patient was successfully operated on. A review of published reports is included.

Cholelithiasis↗
PubMed1989

Regression of herniated nucleus pulposus: two patients with lumbar radiculopathy.

Thirty percent to 95% of patients with lumbar radiculopathy secondary to a bulging or herniated disc improve to a pain-free and functional level with nonsurgical treatment. What happens to the herniated disc material as this improvement occurs is unclear. We present two patients with lumbar radiculopathy documented by physical examination and electrodiagnostic testing. Both patients had herniated disc material at the L5 to S1 level on computed tomography (CT) scans corresponding to the side and level of their lesion on physical examination and electrodiagnostic testing. In both instances, the radiculopathy resolved with conservative treatment. CT scans were repeated in three months on one patient and four months on the other. The scans showed major resolution of the herniated disc material in both patients. These two cases demonstrate that in some patients with proven radiculopathy secondary to herniated nucleus pulposus, the herniated disc material will no longer be visible on CT scan and is presumed to resorb as the symptoms abate.

Adult↗
PubMed1988

Specific binding of insulin-like growth factors 1 and 2 to the type 1 and type 2 receptors respectively.

1. Competitive binding and receptor cross-linking experiments have been used to examine the receptor-ligand interactions between three bovine insulin-like growth factors (IGF) and monolayer cultures of myoblasts and fibroblasts. 2. Labelled IGF-2 bound predominantly to the type 2 receptor with negligible label cross-linked to the type 1 receptor, notwithstanding the ability of IGF-2 to compete effectively for the binding of IGF-1 to the type 1 receptor. Approx. 100-fold higher concentrations of IGF-1 or the N-terminal truncated (des-Gly-Pro-Glu) IGF-1 (-3N:IGF-1) were required to produce competition equivalent to IGF-2. 3. All IGF peptides, but especially IGF-1, enhanced the binding of labelled IGF-2 to the type 2 receptor of lung fibroblasts. This unusual effect was probably a consequence of the displacement of labelled IGF-2 otherwise bound to a medium protein, a conclusion supported by the demonstration of a 38 kDa membrane protein cross-linked to labelled IGF-2. 4. Both IGF-1 and -3N:IGF-1 bound only to the type 1 IGF receptor in L6 myoblasts, rat vascular smooth-muscle cells and human lung fibroblasts. The peptides competed for labelled IGF-1 binding with potencies in the order -3N:IGF-1 greater than IGF-1 greater than IGF-2 much greater than insulin. Since the IGF peptides were equipotent in skin fibroblasts, it was proposed that the apparently higher affinity of -3N:IGF-1 for receptors in the other cell types was instead a consequence of a low affinity of this peptide for the competing 38 kDa binding protein.

Binding, Competitive↗
PubMed1988

Regulation of protein metabolism and DNA synthesis by fibroblast growth factor in BHK-21 cells.

1. Acidic and basic fibroblast growth factors (aFGF, bFGF) were shown to inhibit protein breakdown in BHK-21 cells, with the latter exhibiting approx. 6-fold greater sensitivity. 2. The maximum response achieved was less than observed with insulin or insulin-like growth factor-1 (IGF-1), and was not additive with those growth factors over the 4 h measurement period. The inhibition of protein breakdown followed the same time course with all the growth factors tested, and was enhanced equally by NH4+ ions. Taken together, these results suggest similar mechanisms for effects of the different growth factors on protein breakdown. 3. Protein synthesis was stimulated by bFGF, insulin and IGF-1, with partial additivity evident between bFGF and the other peptides. Increases in cell-culture protein content paralleled the changes in the rate of protein synthesis. 4. DNA synthesis was stimulated more effectively in BHK-21 cells by aFGF or bFGF than by insulin or IGF-1, with partial additivity between the two groups of growth factors. 5. Since each of the growth factors independently produced both relatively rapid effects on protein metabolism and more prolonged increases in DNA synthesis, some caution is warranted before classifying them into truly distinct groups as either competence or progression factors.

Cell Line↗
PubMed1988

Comparison of changes in serum androgen binding protein with germinal epithelial damage and infertility induced by di-n-pentyl phthalate.

Androgen binding protein (ABP), produced by Sertoli cells and released into seminiferous tubules and blood, was measured in the serum of di-n-pentyl phthalate (DPP)-treated rats as a potential index of germinal epithelial damage. A single oral dose of DPP (0, 0.25, 1.0, or 2.0 g/kg body wt in corn oil) was given to four groups of 110 Fischer 344 rats; 10 rats per group were killed weekly for 10 weeks. Effects of treatment on serum ABP were then compared with effects on other reproductive endpoints. Treatment did not produce any significant effect on body weight or weights of liver, kidney, prostate, and seminal vesicles. In high-dose rats, serum ABP values more than doubled 2 days after injection, remained significantly elevated for 3 weeks, then fell and remained significantly below control values from Week 4 through Week 10. Accordingly, 95% of the rats in this group showed greater than 50% of the seminiferous tubules degenerated, decreased epididymal sperm density, reduced testicular and epididymal weights, and up to 97% morphologically abnormal sperm. In medium-dose rats, serum ABP increased up to 48% during the first week, returned to control values by Week 2, and remained at control levels thereafter. Of these rats, 20% showed 20-50% degenerated tubules, decreased sperm density, reduced testicular and epididymal weights (which were not always statistically significant), and up to 23% abnormal sperm morphology. In low-dose rats, serum ABP levels were similar to those of controls, and the other parameters, except sperm density, also remained unchanged. To examine the effects of DPP on fertility, a second group of rats was exposed in an identical manner [gavaged once with DPP in corn oil (0, 0.25, 1.0, and 2.0 g/kg body wt)], then mated to untreated females at 3, 6, and 10 weeks postexposure. DPP at 2 (but not 1.0 or 0.25) g/kg caused a significant reduction in pregnancies and live pups and a significant increase in preimplantation loss. Histopathology of the testis in the first experiment suggested a very slow recovery. Therefore, controls and high-dose rats in the mating trial were killed 14, 18, and 30 weeks after dosing and the germinal epithelium was evaluated histologically. All high-dose animals showed testicular lesions typical of phthalate ester exposure and the epithelium did not recover within 30 weeks.(ABSTRACT TRUNCATED AT 400 WORDS)

Androgen-Binding Protein↗
PubMed1988

The temporal relationship in arterial and venous prostacyclin and thromboxane activity during 24 hours of intraaortic balloon counterpulsation in dogs.

We studied the effects of intraaortic balloon counterpulsation (IABCP) on prostacyclin (PGI2) and thromboxane (TXB2) levels in dogs during 24 hours of 1:1 IABCP or a sham procedure in which the balloon was positioned but left deflated. The arterial PGI2 levels in the IABCP group increased from control values of 95 +/- 20 pg/ml to 268 +/- 95 pg/ml at 1 hour, 429 +/- 95 pg/ml at 4 hours, and 1,884 +/- 532 pg/ml at 24 hours. The arterial PGI2 levels were consistently higher in the IABCP group. Although the TXB2 measurements revealed no significant differences between groups, the IABCP group consistently had a higher level than the sham group. The platelet count in the control group decreased to 45% of baseline levels versus 55% for the IABCP group. We conclude that prolonged IABCP results in either net production of PGI2 or decreased degradation. The correlation between TXB2 and platelet counts is unclear and remains to be defined.

Animals↗
PubMed1988

Effect of changes in dietary sodium on active electrolyte transport by erythrocytes at different stages of human pregnancy.

1. Active electrolyte transport was examined in erythrocytes from women in the second and third trimesters of pregnancy and post partum, and compared with that in ovulating women. 2. There was a significant reduction in intracellular sodium ([Na]i) and increase in intracellular potassium ([K]i) in pregnancy with a return towards normal values in the post-partum period. 3. Maximum specific ouabain binding [number of Na+,K+-adenosine triphosphatase (Na+, K+-ATPase) units] was increased by 70% in pregnancy and returned slowly towards normal values post partum. 4. Na+,K+-ATPase activity as determined by ouabain-sensitive 86Rb influx in artificial media was also increased in pregnancy by 13%. It returned towards normal post partum. 5. The increases in Na+,K+-ATPase in pregnancy were not closely related to the concomitant increases in aldosterone or cholesterol nor to reticulocytosis and were not affected by 7 days of high (greater than 250 mmol/day) or low (less than 50 mmol/day) sodium intake.

Biological Transport, Active↗
PubMed1988

Using the OSCE to measure clinical skills performance in nursing.

The measurement of clinical skills performance continues to pose a challenge for nurse educators. This paper will report on the use of the objective structured clinical examination (OSCE) to measure the psychomotor learning outcomes of a programme designed to assist students to learn to conduct a nursing neurological examination. The OSCE has a tradition in medicine, having been developed by Ronald Harden in Scotland and first reported in the British Medical Journal in 1975. The University of Ottawa has the longest North American experience with this type of evaluation procedure and there is an increasingly rich medical literature referring to the OSCE. Although the OSCE appears to be a promising method for evaluating competence in the performance of clinical skills, there are no studies in the nursing literature examining the use of the OSCE as a method for evaluating the performance of clinical skills by nurses. Our experience suggests that the OSCE may be a powerful tool in the evaluation of clinical competence in nursing and that it may also be an effective facilitator for learning to perform clinical skills in nursing.

Clinical Competence↗
PubMed1988

Alterations in erythrocyte Na+,K+-cotransport in normal and hypertensive human pregnancy.

Many physiological variables known or thought to affect erythrocyte Na+,K+-cotransport are altered in pregnancy. The interrelationships of Na+,K+-cotransport and pregnancy were therefore examined. Values were elevated by more than 30% in both second and third trimesters with a return towards non-pregnant levels in the postpartum period. Although pregnancy was also associated with elevated plasma cholesterol, renin activity and aldosterone, there was no significant relationship within the pregnant group between Na+,K+-cotransport and any of these factors. No change could be demonstrated in Na+,K+-cotransport values after 7 days of either high (greater than 250 mmol/day) or low (less than 50 mmol/day) sodium intake and values for those who developed pregnancy-associated hypertension (PAH, pre-eclampsia) were not significantly different from those in continuously normotensive women in either the second or the third trimesters of pregnancy.

Adult↗