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排序方式: 共有2296条查询结果,搜索用时 15 毫秒
1.
J Canet J Vallés P Vila F Vidal 《Revista espa?ola de anestesiología y reanimación》1990,37(6):366-369
Patients with morbid obesity present a series of functional and morphologic alterations and require a careful planning for anesthetic management. We report a case of a woman weighing 260 kg who was operated on twice for the treatment of her base condition. In the first operation, general anesthesia was carried out and in the second one, epidural anesthesia was conducted. Main complications included hypoxemia and hypercapnia which persisted during the first week after operation carried out under general anesthesia. 相似文献
2.
Luís Mariano Isabel Vila?a Jorge Almeida Mota Garcia Maria Júlia Maciel 《Revista portuguesa de cardiologia》2007,26(3):265-270
Apical ballooning is a novel clinical entity reported in different contexts of physical and psychological stress, which is more common in middle-aged women. Of unknown etiology, the syndrome is characterized by a sudden and transient dilatation of the left ventricular apex in the absence of obstructive atherosclerotic coronary disease or evidence of myocardial necrosis, with total late recovery of ventricular function. The authors report the case of a 53-year-old woman who was admitted to the emergency room with left arm ischemia and low cardiac output, requiring ventilatory support. Left catheterization showed typical medial and apical myocardial dysfunction, with normal coronary arteries. Transesophageal echocardiography revealed a thrombus attached to the lower face of the aortic arch, which probably explained the thromboembolism of the arm but was unlikely to be the cause of the left ventricular dysfunction since there were no enzymatic or electrocardiographic signs of myocardial necrosis and normal wall motion was fully recovered. 相似文献
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F Carmona F Fábregues R Alvarez J Vila V Cararach 《European journal of obstetrics, gynecology, and reproductive biology》1992,45(1):67-70
Morganella morganii, a gram-negative bacterium, usually infects older patients with urinary catheters, but does not commonly affect pregnant women. In this report we present a case of chorioamnionitis caused by Morganella morganii. The case was complicated by a life-threatening Adult Respiratory Distress Syndrome. 相似文献
6.
Eight patients with Alport's syndrome and massive proteinuria (129±60.57 mg/m2 per hour) were treated with cyclosporin A (CyA) for 8 months. The average dose of CyA administered to all patients was 4.21±0.26 mg/kg per day and blood CyA levels of 63.4±4.1 ng/ml were attained. In five patients, proteinuria abated during the 3rd week of treatment. In the remaining three, all of whom had low creatinine clearance (82.0, 46.0 and 43.2 ml/min per 1.73 m2 respectively), proteinuria persisted but at levels lower than before treatment: 32.5±15.9 mg/m2 per hour versus 183.3±29.7 mg/m2 per hour. No permanent decrease in creatinine clearance was observed in any of these patients throughout treatment. In those patients in whom proteinuria abated, it reappeared 2 weeks after discontinuation of CyA treatment. We observed no significant increases in angiotensin II plasma levels in our patients during CyA administration. Although we have shown that CyA will reduce massive proteinuria in patients with Alport's syndrome, we cannot yet recommend its use as a therapeutic measure. 相似文献
7.
This study assesses physiological and subjective effects of traffic noise and the mediator role that negative self-statements play. 84 female students underwent a Physiological Reaction Test to two 15 min presentations of high intensity traffic noise (85-95 dB) under two Noise conditions--with and without negative self-statements. Half of the subjects were given specific instructions to increase the credibility of the self-statements. Dependent variables were frontal EMG, electrodermal variables (conductance level and number of responses) and subjective tension. Traffic noise provoked subjective tension and physiological responses. Only the number of electrodermal responses habituated between noise presentations, the rest of the physiological variables did not habituate. Negative self-statements had the greatest effect on frontal EMG. In fact, only the noise with negative self-statements condition produced a significant EMG increase in the first part of the Test. Instructions increased subjective tension and also increased the effect of the self-statements on the electrodermal variables. The implications of these results for psychosomatic problems and the importance of negative self-statements are discussed. 相似文献
8.
Analysis of heart rate variability (HRV) is a valuable, non-invasive method for quantifying autonomic cardiac control in humans.
Frequency-domain analysis of HRV involving myocardial ischaemic episodes should take into account its non-stationary behaviour.
The wavelet transform is an alternative tool for the analysis of non-stationary signals. Fourteen patients have been analysed,
ranging from 40 to 64 years old and selected from the European Electrocardiographic ST-T Database (ESDB). These records contain
33 ST episodes, according to the notation of the ESDB, with durations of between 40s and 12min. A method for analysing HRV
signals using the wavelet transform was applied to obtain a time-scale representation for very low-frequency (VLF), low-frequency
(LF) and high-frequency (HF) bands using the orthogonal multiresolution pyramidal algorithm. The design and implementation
using fast algorithms included a specially adapted decomposition quadrature mirror filter bank for the frequency bands of
interest. Comparing a normality zone against the ischaemic episode in the same record, increases in LF (0.0112±0.0101 against
0.0175±0.0208s2Hz−1; p<0.1) and HF (0.0011±0.0008 against 0.0017±0.0020s2Hz−1; p<0.05) were obtained. The possibility of using these indexes to develop an ischaemic-episode classifier was also tested.
Results suggest that wavelet analysis provides useful information for the assessment of dynamic changes and patterns of HRV
during myocardial ischaemia. 相似文献
9.
Emotion-modulated startle is a robust phenomenon that has been demonstrated in a wide range of experimental situations. Similarly, heart rate variability (HRV) has been associated with a diverse range of processes including affective and attentional regulation. The present study sought to examine the relationship between these two important measures of affective behavior. Ninety female participants viewed pleasant, neutral, and unpleasant pictures while exposed to acoustic startle stimuli. The eyeblink startle was recorded both during the affective foregrounds and during intertrial intervals. HRV was assessed during a resting baseline and relationships between HRV and startle magnitudes examined. Results indicated that resting HRV was inversely related to startle magnitude during both intertrial intervals and affective foregrounds. In addition, the participants with the highest HRV showed the most differentiated emotion-modulated startle effects, whereas those with the lowest HRV, compared to those with the highest HRV, showed significantly potentiated startle to neutral foregrounds and marginally potentiated startle to pleasant foregrounds. The findings are consistent with models that posit that prefrontal cortical activity modulates subcortical motivation circuits. These results have important implications for the use of startle probe methodology and for HRV in the study of emotional regulation and dysregulation. 相似文献
10.
Role of Elastin in Spontaneously Hypertensive Rat Small Mesenteric Artery Remodelling 总被引:1,自引:1,他引:1
Ana M. Briones José M. González Beatriz Somoza Jesús Giraldo† Craig J. Daly‡ Elisabet Vila M. Carmen González John C. McGrath† Silvia M. Arribas 《The Journal of physiology》2003,552(1):185-195
Chronic hypertension is associated with resistance artery remodelling and mechanical alterations. However, the contribution of elastin has not been thoroughly studied. Our objective was to evaluate the role of elastin in vascular remodelling of mesenteric resistance arteries (MRA) from spontaneously hypertensive rats (SHR). MRA segments from Wistar Kyoto rats (WKY) and SHR were pressurised under passive conditions at a range of physiological pressures with pressure myography. Confocal microscopy was used to determine differences in the quantity and organisation of elastin in intact pressure-fixed arteries. To assess the contribution of elastin to MRA structure and mechanics, myograph-mounted vessels were studied before and after elastase incubation. When compared with WKY, MRA from SHR showed: (1) a smaller lumen, (2) decreased distensibility at low pressures, (3) a leftward shift of the stress-strain relationship, (4) redistribution of elastin within the internal elastic lamina (IEL) leading to smaller fenestrae but no change in fenestrae number or elastin amount. Elastase incubation (1) fragmented the structure of IEL in a concentration-dependent fashion, (2) abolished all the structural and mechanical differences between strains, and (3) decreased distensibility at low pressures. The study shows the overriding role of elastin in determining vascular dimensions and mechanical properties in a resistance artery. In addition, it informs hypertensive remodelling. MRA remodelling and increased stiffness are accompanied by elastin restructuring within the IEL and elastin degradation reverses structural and mechanical alterations of SHR MRA. Differences in elastin organisation are, therefore, a central element in small artery remodelling in hypertension. 相似文献