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1.
V Aerra M Kuduvalli AN Moloto AK Srinivasan AD Grayson BM Fabri AY Oo 《Journal of cardiothoracic surgery》2006,1(1):6-5
Background
Atrial fibrillation can occur in up to 40% of patients undergoing coronary surgery. 相似文献2.
Paul Wexberg MD BM Richard Pacher MD Suzanne Rdler MD Katharina Kiss MD Gilbert Beran MD Michael Grimm MD Gerald Maurer MD Dietmar Glogar MD FESC 《The Journal of heart and lung transplantation》2002,21(12):583-1263
BACKGROUND: Endothelin, a peptide with strong vasoconstrictive and mitogenic properties, has been found to increase after cardiac transplantation. We therefore assessed the association between its precursor peptide, big endothelin-1, and intimal hyperplasia and coronary flow reserve after heart transplantation. METHODS: Thirty-five patients without hemodynamically significant coronary artery disease after heart transplantation were investigated: Average peak flow velocity in the left anterior descending artery (LAD) was assessed by intracoronary Doppler at baseline as well as after injection of adenosine; coronary flow reserve was calculated as a ratio of both and was corrected for patient age and baseline average peak flow velocity. Lumen, intima + media and total vessel area were measured by intracoronary ultrasound. The plasma concentration of big endothelin-1 in venous blood was determined by radioimmunoassay. RESULTS: Patients with elevated big endothelin-1 levels (>2 fmol/ml) tended to have a decreased corrected coronary flow reserve (2.60 +/- 0.9 vs 3.21 +/- 1.0, p = 0.078). They also had a significantly larger intima + media area (5.82 +/- 2.9 vs 2.37 +/- 2.9 mm(2), p = 0.004) and total vessel area (18.36 +/- 5.8 vs 12.81 +/- 4.8 mm(2), p = 0.012) than those with normal plasma concentrations. CONCLUSIONS: Our study suggests an association between elevated big endothelin-1 plasma levels and the development of intimal hyperplasia and reduction of coronary flow reserve after cardiac transplantation. 相似文献
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A randomized controlled trial of sedation in the critically ill 总被引:2,自引:0,他引:2
LYNN PARKINSON RSCN JULIE HUGHES RSCN REA GILL MSc IMOGEN BILLINGHAM BM FRCA JANE RATCLIFFE MB ChB FRCP & IMTI CHOONARA MD MRCP 《Paediatric anaesthesia》1997,7(5):405-510
A randomized controlled trial comparing: a) a combination of oral chloral hydrate and promethazine to b) a continuous intravenous midazolam infusion, for maintenance sedation in critically ill children, was carried out. The level of sedation was assessed four hourly using a specifically devized sedation scale. Forty-four children entered the study of whom two were subsequently excluded. The number of satisfactory assessments (desired and actual levels of sedation equal) was significantly greater in the chloral hydrate and promethazine group (Chi-squared P <0.01; confidence intervals of the difference 0.06 to 0.20). The number of assessments at level 5 on the sedation scale (patient restless/distressed) was significantly greater in the midazolam group (Chi-squared P <0.05). The total number of satisfactory assessments in the two groups were only 61 and 48% respectively, suggesting that sedation can be considerably improved. Chloral hydrate and promethazine are more effective than midazolam as maintenance sedation in critically ill children. It is possible to prospectively study the efficacy of sedative drugs in critically ill children. 相似文献
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Lesley Barclay RN CM BA MEd Louise Everitt RN CM Post Grad Dip-Comm Health Frances Rogan RN CM B App S M Com Nurs Virginia Schmied RN CM BA MA Hons Aileen Wyllie RN CM BA MHPEd 《Journal of advanced nursing》1997,25(4):719-728
This paper presents the results of a qualitative study conducted by midwife researchers into women's experience of new motherhood. Data were collected using focus groups involving 55 first-time mothers and analysed using grounded theory method. The analysis produced six categories: 'realizing', 'unready', 'drained', 'aloneness', 'loss' and 'working it out'. The core category, 'becoming a mother', integrates all other categories and encapsulates the process of change experienced by women. Also explained are factors mediating the often distressing experience of becoming a mother. The analysis provides a conceptualization of early motherhood enabling the development of strategies for midwives, nurses and others helping women negotiate this challenge. 相似文献
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The computerized database system described was initially developed in 1986 to facilitate analysis of retrospective head and neck cancer data from the Royal Adelaide Hospital Department of Otolaryngology. This has now been expanded to become an on-going patient information management system. It is based on the dBase-III-Plus database package and is implemented on an IBM XT compatible computer. The system was designed to be used by staff without specialist computer skills and is therefore largely “menu-driven.” The main functions include patient record creation, update, and retrieval, and the production of reports including graphical presentations. There is also a powerful but easy to use query facility. The system has already provided much useful epidemiological material but is now beginning to fulfill an even more important role in patient follow-up and in assisting evaluation of alternative treatment protocols. 相似文献
10.
Aimonetti JM Vedel JP Schmied A Pagni S 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2000,133(3):391-401
The question of whether Ia reciprocal inhibition might depend on the motor task and on the type of motor unit activated was investigated in the human extensor carpi radialis muscles. Ia reciprocal inhibition induced by stimulating the median nerve (conditioning stimulation) was estimated by measuring the changes in the firing probability of 37 extensor motor units in response to the radial nerve stimulation (100 test stimuli) delivered 1 ms after the conditioning stimulation. Six subjects were asked to perform a task consisting of either selectively contracting their wrist extensor muscles or co-activating their wrist and finger antagonist muscles by clenching their hand around a manipulandum. In the control recordings (test stimulation alone), the mean response probability of the 37 motor units was found to be greater during hand clenching. The motor units were identified on the basis of their force thresholds, their macro-potentials, and their twitch contraction times. The data obtained in the control recordings were consistent with the size principle. In the recordings where the responses were conditioned by applying median nerve stimulation, the response probability of the motor units with low force thresholds, small macro-potential areas, and long twitch contraction times tended to decrease, in line with the presence of Ia reciprocal inhibition, whereas the response probability of the motor units with higher force thresholds, larger macro-potential areas, and shorter twitch contraction times tended to increase. The median nerve stimulation may therefore have altered the efficiency with which the extensor Ia inputs recruited the homonymous motoneurones in the pool. The flexor group I afferents activated while the median nerve was stimulated had inhibitory effects on the slow contracting motor units, and facilitatory effects mainly on the fast contracting motor units. Both of these effects were stronger during hand clenching, in which the numerous cutaneous receptors of the palm and fingertips are liable to be activated. Besides their own effects on the excitability of the various types of motor units, cutaneous inputs are known to potentiate the Ib interneurones. In addition, the effects of the conditioning stimulation were superimposed on the tonic activity of the Ia and Ib afferents from the flexor wrist and finger muscles. This may explain why both the inhibitory and facilitatory effects of the median nerve stimulation were enhanced during hand clenching. 相似文献