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11.
Elbert T Dworkin BR Rau H Pauli P Birbaumer N Droste C Brunia CH 《International journal of behavioral medicine》1994,1(3):215-228
Activating the arterial baroreceptors in animals has been shown to blunt pain sensation and provide other forms of central
nervous system inhibition. This study tested the hypothesis that, among human subjects, a tonic increase in blood pressure
(BP) could be a learned response to environmental stressors among subjects in whom the baroreceptor inhibitory mechanism is
active. In a sample of 96 healthy, normotensive men and women, amount of pain-reduction produced by baroreceptor stimulation
predicted an increase in resting BP 20 months later: the increase was proportional to self-assessed daily life stress. Among
the subjects reporting the greatest amount of stress, the pain inhibition effect accounted for more than 80% of the BP variance.
These results support the hypothesis that the reduction in perceived stress produced by baroreceptor stimulation may reward
learned increases in BP.
This research was supported by Deutsche Forschungsgemeinshaft Grant EL 101/3 to Thomas Elbert and National Institutes of Health
Grant ROl HL40837 to B. R, Dworkin. 相似文献
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13.
Prevalence and frequency of microembolic signals in 105 patients
with extracranial carotid artery occlusive disease 总被引:4,自引:0,他引:4
D. Droste R. Dittrich V. Kemeny G. Schulte-Altedorne... E Ringelstein 《Journal of neurology, neurosurgery, and psychiatry》1999,67(4):525-528
Besides the established factors "presence of symptoms" and "degree of stenosis", plaque echolucency is considered to be associated with increased risk of stroke in patients with carotid artery disease. An evaluation was carried out as to whether the prevalence and number of microembolic signals (MES) detected by transcranial Doppler ultrasound were higher in patients with echolucent carotid plaques. One hundred and five patients with carotid artery stenosis from 20%-99% or occlusion underwent clinical investigations, duplex ultrasound of the carotid arteries, and a 1 hour recording from the middle cerebral artery downstream to the carotid artery pathology using the four gate technique. The presence of MES was more frequent and the number greater in symptomatic patients (21 out of 64 patients (33%); mean number of MES in all 64 patients 3.1) than in asymptomatic patients (four out of 41 patients (10%); mean number of MES in all 41 patients 0.3) (p=0.007, and p=0.006, respectively). Echogenicity of the lesions did not affect either number or presence of MES. Positivity for MES and the number of MES increased with increasing degree of stenosis (both p=0.002). Four out of 12 patients with carotid artery occlusion showed MES. No MES could be detected in carotid artery stenosis below 80%. There was a decline in positivity of MES and of the number of MES with the time after the ischaemic event. After 80 days or more after the index event, only one patient showed MES. In conclusion, increasing degree of stenosis and presence of symptoms similarly affect macroembolic and microembolic risk. Thus MES may be a surrogate parameter for risk of stroke. The presence of MES in a few asymptomatic patients suggests that clinically silent circulating microemboli may give additional information on the pending embolic potential of carotid artery stenoses. Echolucency of the plaque was not related to an increased number of MES. 相似文献
14.
Using a thyroid disease‐free population to define the reference interval for TSH and free T4 on the Abbott Architect analyser 下载免费PDF全文
15.
16.
Tammo A. Brouwer Charina van den Boogaard Eric N. van Roon Cor J. Kalkman Nic Veeger 《Journal of clinical monitoring and computing》2018,32(6):1117-1126
Ultrasound scanning of bladder volume is used for prevention of postoperative urinary retention (POUR). Accurate assessment of bladder volume is needed to allow clinical decision-making regarding the need for postoperative catheterization. Two commonly used ultrasound devices, the BladderScan® BVI 9400 and the newly released Prime® (Verathon Medical®, Bothell, WA, USA), with or without the ‘pre-scan’ option, have not been validated in clinical practice. The aim of this study was to assess the performance of these devices in daily clinical practice. Between June and September 2016 a prospective observational study was conducted in 318 surgical patients (18 years or older) who needed a urinary catheter perioperatively for clinical reasons. For acceptable performance, we required that the volume as estimated by the BladderScan® differs by no more than 5% from the actual urine volume after catheterization. The Schuirmann’s two one-sided test was performed to assess equivalence between the BladderScan® estimate and catheterization. The BVI 9400® overestimated the actual bladder volume by +?17.5% (95% CI +?8.8 to +?26.3%). The Prime® without pre-scan underestimated by ? 4.1% (95% CI ? 8.8 to +?0.5%) and the Prime® with pre-scan underestimated by ? 6.3% (95% CI ? 11.6 to ? 1.1%). This study shows that while both ultrasound devices were able to approximate current bladder volume, both BVI 9400® and Prime®—with and without pre-scan—were not able to measure the actual bladder volume within our predefined limit of ±?5%. Using the pre-scan feature of the Prime® did not further improve accuracy. 相似文献
17.
The role of hydroxychloroquine in the treatment of lichen planopilaris: A retrospective case series and review 下载免费PDF全文
A variety of systemic agents are used to treat lichen planopilaris (LPP) with a limited evidence base. The aim of our study was to retrospectively review the response rate to and tolerability of hydroxychloroquine in a cohort of patients with LPP in an effort to add to the evidence base for its use. Twenty‐three patients with a clinical and histopathological diagnosis of LPP who had been treated with hydroxychloroquine for their disease in a single center were identified. A retrospective review of these patients' medical records was performed and physician rated response was documented. Complete response was observed in 61% of our patients, and a further 9% of patients demonstrated partial response. Thirteen percent of patients withdrew from treatment because of suspected adverse effects. Our sample size was small, and data was collected retrospectively. We found hydroxychloroquine to be a reasonable therapeutic choice in LPP. 相似文献
18.
We studied the effects of long-term (i.e. 4 wk) voluntary exercise on the hypothalamic-pituitary-adrenocortical (HPA) axis in male mice. Voluntary exercise was provided by giving mice access to a running wheel, in which they indeed ran for about 4 km/d. Exercising mice showed similar body weights as control animals but presented less abdominal fat, lighter thymuses, and heavier adrenal glands. Exercise resulted in asymmetric structural changes in the adrenal glands. Whereas control mice had larger left than right adrenals, this condition was abolished in exercising animals, mainly because of enlargement of the right adrenal cortex. Tyrosine hydroxylase mRNA expression in the adrenal medullas of exercising mice was increased. In exercising mice, early-morning baseline plasma ACTH levels were decreased, whereas plasma corticosterone levels at the start of the dark phase were twice as high as those in control animals. To forced swimming and restraint stress, exercising mice responded with higher corticosterone levels than those of the control animals but with similar ACTH levels. However, if exposed to a novel environment, then exercising mice presented decreased ACTH responses. Interestingly, exercising mice showed a decreased corticosterone response to novelty only when the novel environment contained a functioning running wheel. Glucocorticoid receptor levels were unchanged, whereas mineralocorticoid receptor levels were decreased, in hippocampus of exercising animals. Corticotropin-releasing factor mRNA levels in the paraventricular nucleus were lower in exercising mice. Thus, voluntary exercise results in complex, adaptive changes at various levels within the HPA axis as well as in sympathoadrenomedullary and limbic/neocortical afferent control mechanisms. These changes seem to underlie the differential responsiveness of the HPA axis to physical vs. emotional challenges. 相似文献
19.
Potential challenges facing distributed leadership in health care: evidence from the UK National Health Service 下载免费PDF全文
Graeme Martin Nic Beech Robert MacIntosh Stacey Bushfield 《Sociology of health & illness》2015,37(1):14-29
The discourse of leaderism in health care has been a subject of much academic and practical debate. Recently, distributed leadership (DL) has been adopted as a key strand of policy in the UK National Health Service (NHS). However, there is some confusion over the meaning of DL and uncertainty over its application to clinical and non‐clinical staff. This article examines the potential for DL in the NHS by drawing on qualitative data from three co‐located health‐care organisations that embraced DL as part of their organisational strategy. Recent theorising positions DL as a hybrid model combining focused and dispersed leadership; however, our data raise important challenges for policymakers and senior managers who are implementing such a leadership policy. We show that there are three distinct forms of disconnect and that these pose a significant problem for DL. However, we argue that instead of these disconnects posing a significant problem for the discourse of leaderism, they enable a fantasy of leadership that draws on and supports the discourse. 相似文献
20.