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101.
OBJECTIVES: The difference between clinic and daytime ambulatory blood pressure is referred to as the white-coat effect. In this study, we investigated (i) the magnitude of the white-coat effect in subjects with different daytime ambulatory blood pressure levels, and (ii) the association of the white-coat effect with left ventricular mass. METHODS: A total of 1581 subjects underwent clinic blood pressure readings, 24-h ambulatory blood pressure monitoring and left ventricular echocardiographic assessment. Their mean daytime systolic blood pressure varied from 88.0 to 208.9 mmHg and their mean daytime diastolic blood pressure from 40.3 to 133.0 mmHg. RESULTS: A negative correlation was found between the systolic or diastolic white-coat effect and the systolic or diastolic daytime ambulatory blood pressure (r = -0.22, P < 0.000 and r = -0.50, P < 0.000, respectively). Left ventricular mass significantly correlated with ambulatory blood pressure (P < 0.001), but there was no association between left ventricular mass and clinic blood pressure or white-coat effect. Furthermore, the white-coat effect was reversed at the highest level of systolic or diastolic daytime ambulatory blood pressure (systolic over 170 mmHg or diastolic over 100 mmHg) when systolic or diastolic daytime ambulatory blood pressure was higher than systolic or diastolic clinic blood pressure (ambulatory blood pressure hypertension). CONCLUSIONS: The white-coat effect shows an inverse association with daytime ambulatory blood pressure level (systolic or diastolic), being significantly more prominent for levels below 140/80 mmHg for systolic/diastolic daytime ambulatory blood pressure and reversed with daytime ambulatory blood pressure levels above 170/100 mmHg.  相似文献   
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Occupational-related allergic sensitization has been reported in fishery workers. The aim of this study was to investigate the prevalence, work-related symptoms, and possible risk factors in this occupationally exposed population in Greece. Sixty-four fish and seafood processing workers were compared with 60 controls regarding sensitization to seafood allergens. All participants underwent skin-prick tests (SPTs) with cod, sardines, shrimp, spiny lobster, crabs, salmon, mussels, and trout plus negative and positive control. The level of specific IgE (radioallergosorbent test) was evaluated in subjects with positive SPTs. Sensitization criteria were both SPTs and the corresponding positive radioallergosorbent test. Atopic status was tested with SPTs to seven common inhalant allergens. Potential risk factors for IgE sensitization were investigated using logistic regression analysis. Twenty-three of 64 workers (35.9%) were sensitive to at least one of the seafood allergens tested, and the prevalence in the control group was 10% (6/60; odds ratio, 5.049; 95% CI, 1.884-13.533). The prevalence of sensitization in allergen species tested in the fishery workers group was shrimp, 12.5%; spiny lobster, 10.9%; mussels, 7.8%; crabs 3.1%; cod, 3.1%; sardines, 1.6%; salmon, 1.6%; and trout, 1.6%. Presence of atopy (p = 0.02), intensity (p = 0.03), and duration of exposure (p = 0.03) was found as potential risk factors for IgE sensitization. Four of 64 (6.25%) workers reported work-related symptoms. Occupational exposure to fish and seafood significantly increases the likelihood of sensitization in seafood allergens and atopy, duration, and intensity of exposure may represent potential risk factors in seafood processing workers.  相似文献   
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The correct timing of aortic valve replacement in chronic aortic stenosis or regurgitation is a very important and sometimes difficult task for physicians caring for patients with aortic valve disease. In this review, we will present the current available literature regarding the appropriate management of these patients.  相似文献   
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The endocannabinoid system (ES) is comprised of cannabinoid (CB) receptors, their endogenous ligands (endocannabinoids), and proteins responsible for their metabolism. Endocannabinoids serve as retrograde signaling messengers in GABAergic and glutamatergic synapses, as well as modulators of postsynaptic transmission, that interact with other neurotransmitters. Physiological stimuli and pathological conditions lead to differential increases in brain endocannabinoids that regulate distinct biological functions. Furthermore, endocannabinoids modulate neuronal, glial, and endothelial cell function and exert neuromodulatory, anti‐excitotoxic, anti‐inflammatory, and vasodilatory effects. Analgesia is one of the principal therapeutic targets of cannabinoids. Cannabinoid analgesia is based on the suppression of spinal and thalamic nociceptive neurons, but peripheral sites of action have also been identified. The chronic pain that occasionally follows peripheral nerve injury differs fundamentally from inflammatory pain and is an area of considerable unmet therapeutic need. Over the last years, considerable progress has been made in understanding the role of the ES in the modulation of pain. Endocannabinoids have been shown to behave as analgesics in models of both acute nociception and clinical pain such as inflammation and painful neuropathy. The framework for such analgesic effects exists in the CB receptors, which are found in areas of the nervous system important for pain processing and in immune cells that regulate the neuro‐immune interactions that mediate the inflammatory hyperalgesia. The purpose of this review is to present the available research and clinical data, up to date, regarding the ES and its role in pain modulation, as well as its possible therapeutic perspectives.  相似文献   
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The multidimensional issue of pain in relation to the need for efficient treatment has been the focus of extensive research. Gaining insight into the molecular mechanisms of pain and identifying specific genes and proteins as possible drug targets is strongly required considering that not all patients can be adequately treated with the currently available drugs. This up‐to‐date review aimed to summarize the findings of recent proteomic and genomic approaches in different types of pain to comment on their potential role in pain signaling pathways and to evaluate their possible contribution to the development of novel and possibly more targeted pain therapeutic strategies. Although pain treatment strategies have been greatly improved during the past century, no ideal targeted pain treatment has been developed. The development of modern and accurate platforms of technology for the study of genetics and physiology of pain has led to the identification of an increased number of altered genes and proteins that are involved in pain‐related pathways. Through genomics and proteomics, pain‐related genes and proteins, respectively, may be identified as diagnostic markers or drug targets improving therapeutic strategies. Furthermore, such molecular mediators of pain may reveal novel strategies for individualized pain management. The utilization of unique experimental approaches (through specific animal models) as well as powered genetic association studies conducted on appropriate populations is more than essential.  相似文献   
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BACKGROUND: Early diagnosis of heart transplant rejection is mandatory, since even mild rejection can rapidly progress to more severe rejection. Noninvasive diagnosis of heart transplant rejection still remains a challenge. HYPOTHESIS: The purpose of the study was to determine a possible association between myocardial performance index (MPI) and biopsy score of the heart transplant. METHODS: This is a retrospective cohort analysis of 99 complete Doppler echocardiographic studies from 24 consecutive patients (23 men) performed within 24 h of endomyocardial biopsy. Mean age of the cohort was 50 +/- 9 years and mean time from transplantation was 19 +/- 21 months (1-81). All patients were in sinus rhythm. Myocardial performance index was calculated as the ratio of isovolumic contraction time plus isovolumic relaxation time divided by ejection time. Left ventricular dimensions, left ventricular mass, ejection fraction, and a number of Doppler indices (E-point velocity, A-point velocity, deceleration time, and deceleration slope) were also measured. The International Society for Heart and Lung Transplantation (ISHLT) grading system was used for the classification of endomyocardial biopsies. RESULTS: Myocardial performance index was significantly prolonged (0.60 +/- 0.13, 0.68 +/- 0.08, 0.75 +/- 0.20, in biopsy scores 0, IA, and IB, respectively; p<0.001). Isovolumic contraction time was significantly prolonged; isovolumic relaxation time was not significantly changed. Ejection time and deceleration time were significantly shortened. Multivariate stepwise regression analysis revealed that MPI and deceleration time were the only independent predictors of biopsy score (r=0.48, F=10.53, p<0.0001). CONCLUSION: Myocardial performance index seems to be a useful adjunct in the follow-up of cardiac transplant patients. These preliminary data suggest that a larger study may be indicated to clarify the relevance of myocardial performance index.  相似文献   
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