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41.
This commentary is referred to the review signed by Rattemborg [N.C. Rattenborg, Evolution of slow wave sleep and palliopallial connectivity in mammals and birds. A hypothesis. Brain Res. Bull. 69 (2006) 20-29]. We propose that the review missed important aspects in relation to the characteristics of sleep in poikilotherm vertebrates and in the evolution of sleep. Poikilotherms continuously show an EEG dominated by slow waves, but its highest amplitude appears not during sleep, but during active waking. In addition, they show an arousal reaction which consists in an increase in EEG amplitude and synchrony, opposite to mammals and birds. As a consequence, most of the conclusions proposed in the review should be rejected.  相似文献   
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Chordoid glioma of the third ventricle is an infrequent brain tumour that was described for the first time by Brat et al. in 1998; since then, only 39 cases have been reported. We present a new case of chordoid glioma of the third ventricle in a 51-year-old-man that was treated with total surgical removal, with a good initial postoperative evolution. Sudden death, most likely due to a massive pulmonary embolism, occurred in the third postoperative day. We present the histological characteristics of the tumour and review the literature regarding this entity.  相似文献   
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Diabetic nephropathy (DN) is the leading cause of end stage renal disease (ESRD). Although the pathogenesis of DN is multifactorial, local inflammatory stress may result from both the metabolic and hemodynamic derangements observed in DN. Inflammatory markers such as Interleukin-18 and Tumor Necrosis Factor (TNF)-alpha are increased in the serum of patients with diabetes and DN. This occurs at a very early stage of disease, and correlates with the degree of albuminuria. Recent data suggest that standard pharmacologic interventions for DN, such as angiotensin converting enzyme inhibitors, angiotensin receptor blockers and aldosterone antagonists, may have anti-inflammatory properties that are independent of their hemodynamic effect. Although inflammation is traditionally thought of as a process resulting in macrophage infiltration, current scientific progress has lead to the novel idea that even cells distant from the blood stream, such as podocytes, can produce cytokines and can express molecules that are part of the co-stimulatory pathway. A strong translational research effort is currently aimed at defining the role of such molecules in cells other than lymphocytes and macrophages. Experimental animal models have recently provided evidence that some acute phase markers of inflammation such as intracellular cell adhesion molecule-1 (ICAM-1), TNF-alpha and Monocytes Chemoattractant Protein-1 (MCP-1) may have a causative role in the development of DN. Here, we review the current evidence supporting the role of inflammation in the early phases of clinical and experimental DN. A complete understanding of inflammatory pathways activated in DN may lead to the discovery of earlier and more reliable markers of DN than albuminuria and the identification of novel therapeutic targets.  相似文献   
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BACKGROUND: Chlamydia pneumoniae has been associated with coronary artery disease by both seroepidemiological studies, and by direct detection of the micro-organism in atherosclerotic lesions. This bacteria could play a potential role in the development of acute coronary events. We examined coronary arteries from patients with unstable angina in order to verify an endovascular presence of C. pneumoniae, and to determine if there is any relationship between serology of acute infection by this pathogen and its presence inside the atherosclerotic plaque of these patients. METHODS: We analysed a total of 76 atherosclerotic plaques obtained from 45 patients who underwent coronary artery bypass surgery. In all patients unstable angina was present within the prior 3 weeks. The presence of C. pneumoniae in the plaque was determined by nested polymerase chain reaction (PCR). Antichlamydial immunoglobulin G (IgG), A (IgA) and M (IgM) was examined by microimmunofluorescence and compared to the PCR result. FINDINGS: DNA of C. pneumoniae was detected in 57 (75%) of 76 atherosclerotic lesions. In most cases (74/76: 97%) a positive IgA, IgM or IgG result was seen. Seven (12%) and 54 (94%) of the 57 PCR positive plaques came from patients with a positive IgM and IgA result, respectively. There was no statistical significant difference between PCR positive and PCR negative plaques in patients with a positive or negative serological result. Clinical characteristics were similarly distributed in patients with and without infected lesions. INTERPRETATION: C. pneumoniae organisms are frequently found in the atherosclerotic lesions of patients undergoing coronary surgery for unstable angina. Neither serological results of acute or recent infection by C. pneumoniae nor clinical characteristics are useful in predicting the individual risk of harbouring C. pneumoniae in the coronary lesions of patients with unstable angina.  相似文献   
46.
Risk factors for hepatocellular carcinoma in patients with liver cirrhosis.   总被引:1,自引:0,他引:1  
OBJECTIVE: Although cirrhosis is known to predispose toward hepatocellular carcinoma (HCC), there is no agreement on the factors that can influence the risk for HCC in patients with cirrhosis. This study was designed to identify differences in cirrhosis-related risk factors for developing HCC in relation to epidemiological characteristics, stage of the disease and etiology. METHODS: 512 patients from southwestern Spain with Child-Pugh stage A or B cirrhosis were examined periodically by ultrasonography, and alpha-fetoprotein (AFP) concentration was measured. RESULTS: The average length of follow-up was 37 months. A total of 52 cases of HCC were detected, which represented a risk of 17% after 5 years of follow-up. The Cox model showed that the risk of HCC increased by 8% per year of increasing age. Male sex (relative risk: 3.4), hepatitis C virus infection (relative risk: 4.6), hepatitis B virus infection (relative risk: 2.9) and AFP levels higher than 15 ng/ml (relative risk: 2.5) were also shown to be risk factors. Among alcoholic patients, only age (risk increased by 15% per year), and hepatitis C virus infection (relative risk: 5.4) were risk factors for HCC. However, in patients infected by hepatitis C virus, the main risk factors were age (relative risk increased by 8% per year), male sex (relative risk: 3.9), co-infection with hepatitis B virus (relative risk: 4.9), and increased AFP (relative risk: 2.8). Of the patients with HCC, 71% were infected with hepatitis C virus. Alcoholism, Child-Pugh stage and duration of cirrhosis did not increase the risk of the appearance of HCC. CONCLUSIONS: The risk of HCC increased to 17% after 5 years of follow-up in patients with Child-Pugh stage A or B cirrhosis. Hepatitis C virus infection was the main risk factor in patients with cirrhosis. Other risk factors were age, male sex, hepatitis B virus infection and altered AFP level.  相似文献   
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ABSTRACT

Chronic obstructive pulmonary disease is progressive and in its advanced stage is associated with major disability. Previous studies suggest that patients with this disease receive little palliative care, even in very advanced stages. Given this, our objectives were to describe the clinical practice of Spanish pulmonologists in the care of patients with end-stage chronic obstructive pulmonary disease, to identify potential barriers to implementing palliative care in these patients and to correlate these responses with doctor's years of experience. A link to an online survey was sent to pulmonologists on (a) symptom management, (b) structure of their department and collaboration with other services, (c) specialized medical training in palliative care, (d) communication with patients and their families, and (e) limiting barriers identified in the management of these patients. A total of 387 responses were received. The majority used opioids to treat dyspnea (52.9%) or pain (54.2%) and many treated anxiety/depression (41%). Around half of the respondents had no established routines in their departments to offer palliative care to patients with chronic obstructive pulmonary disease. There was little communication with end-of-life patients and their families on disease course, mainly associated with a lack of medical training (83% of cases) and changes in patient wishes regarding care through the disease course (81%). In our setting, communication with end-of-life patients with chronic obstructive pulmonary disease is poor. The key challenges identified are insufficient medical training and changing desires of patients. No substantial differences in attitude were found as a function of experience.  相似文献   
50.
“Frontiers in Fontan Failure” was the title of a 2015 conference sponsored by Children's Healthcare of Atlanta and Emory University School of Medicine. In what is hoped to be the first of many such gatherings, speakers and attendees gathered to discuss the problem of long‐term clinical deterioration in these patients. Specific focuses included properly defining the problem and then discussing different treatment strategies, both medical and surgical. The health of the liver after Fontan palliation was a particular point of emphasis, as were quality of life and future directions.  相似文献   
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