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991.
Journal of Interventional Cardiac Electrophysiology - Atrial fibrillation is associated with an increased risk of cognitive impairment. It is unclear whether the restoration of sinus rhythm with...  相似文献   
992.
Heart Failure Reviews - Previous primary studies have explored the association between blood pressure (BP) and mortality in ambulatory heart failure (HF) patients reporting varying and contrasting...  相似文献   
993.
Heart Failure Reviews - Cardiac amyloidosis, once considered a rare disease, has garnered significant attention over the last few years due to three key reasons: first, increased...  相似文献   
994.
Purpose

The identification of subgroups of obstructive sleep apnea (OSA) is critical to understand disease outcome and treatment response and ultimately develop optimal care strategies customized for each subgroup. In this sense, we aimed to perform a cluster analysis to identify subgroups of individuals with OSA based on clinical parameters in the Epidemiological Sleep Study of São Paulo city (EPISONO). We aimed to analyze whether or not subgroups remain after 8 years, since there is not any evidence showing if these subtypes of clinical presentation of OSA in the same population can change overtime.

Methods

We used data derived from EPISONO cohort, which was followed over 8 years after baseline evaluation. All individuals underwent polysomnography, answered questionnaires, and had their blood collected for biochemical examinations. OSA was defined according to AHI?≥?15 events/h. Cluster analysis was performed using latent class analysis (LCA).

Results

Of the 1042 individuals in the EPISONO cohort, 68% agreed to participate in the follow-up study (n?=?712), and 704 were included in the analysis. We were able to replicate the OSA 3-cluster solution observed in previous studies: disturbed sleep, minimally symptomatic and excessively sleepy in both baseline (36%, 45% and 19%, respectively) and follow-up studies (42%, 43%, and 15%, respectively). The optimal cluster solution for our sample based on Bayesian information criterion (BIC) was 2 cluster for baseline (disturbed sleep and excessively sleepy) and 3 clusters for follow-up (disturbed sleep, minimally symptomatic, and excessively sleepy). A total of 45% of the participants migrated clusters between the two evaluations (and the factor associated with this was a greater delta-AHI (B?=????0.033, df?=?1, p?=?0.003).

Conclusions

The results replicate and confirm previously identified clinical clusters in OSA which remain in the longitudinal analysis, with some percentage of migration between clusters.

  相似文献   
995.
Purpose  This study analyzed whether prehospital or in-hospital delay was the more significant influence on perforation rates for acute appendicitis and whether any clinical feature designated patients requiring higher surgical priority. Methods  A retrospective analysis was conducted over one year at a tertiary referral hospital without a dedicated emergency surgical theater. Admission notes, theater logbook, and the Hospital Inpatient Enquiry system were reviewed to identify the characteristics and clinical course of patients aged greater than 16 years who were operated upon for histologically confirmed acute appendicitis. Results  One hundred and fifteen patients were studied. The overall perforation rate was 17 percent. The mean duration of symptoms prior to hospital presentation was 38.1 hours with the mean in-hospital waiting time prior to operation being 23.4 hours. Although body temperature on presentation was significantly greater in patients found to have perforated appendicitis (P < 0.05), only patient heart rate at presentation and overall duration of symptoms, but not in-hospital waiting time, independently predicted perforation by stepwise linear regression modeling. Conclusion  In-hospital delay was not an independent predictor of perforation in adults with acute appendicitis although delays may contribute if patients are left to wait unduly. Tachycardia at presentation may be a quantifiable feature of those more likely to have perforation and who should be given higher surgical priority.  相似文献   
996.
An attempt was made to elaborate an optimal method for noninvasive radionuclide determination of left ventricular ejection fraction in conscious and lightly anaesthetized dogs, as well as to assess the value of this procedure in estimating cardiac functional state. Repeated determinations in the same animals have shown that the 45 degree left anterior oblique position (LAO-45) for imaging is optimal, giving the most uniform values of the calculated left ventricular ejection fraction. Neither the latter, nor the haemodynamic parameters (LVSP, LVEDP and dP/dt) determined by invasive methods were changed by light pentobarbital anaesthesia (20 mg/kg i. v.). Results confirm the validity of noninvasive radionuclide determination of left ventricular ejection fraction for estimation of the functional state and of the pharmacological actions on the latter in both conscious and anaesthetized animals.  相似文献   
997.
A young patient presented with unconsciousness, cardiac arrhythmias, arterial hypotension, and mild intravascular hemolysis after intentional inhalation of chloroform. After the initial complications had resolved, nausea, loss of appetite, and mild transitory jaundice developed. Chloroform-associated hepatotoxicity was biochemically and histologically documented. Facilitating factors included long-term moderate alcohol consumption and an initial episode of arterial hypoxemia. Chloroform inhalation for recreational purposes is probably uncommon. Yet, because of its delayed onset, chloroform poisoning should be considered in acute liver disease without a clear antecedent cause.  相似文献   
998.
Progenitor cell failure in the erythroid lineage is a particular problem in bone marrow failure. To provide insight into early erythopoietic development we used sensitive techniques to examine the effects of SCF, IL-3 and MIP-1α on two developmentally arrested progenitor cell lines, HEL and K562. Quantitative flowcytometric analysis showed that both expressed receptors (SCF > MIP-1α >IL-3). Qualitative analysis revealed HEL cells expressed more receptors than K562 cells. Clonogenic assays with sensitive haemoglobin detection showed that SCF and IL-3 did not support HEL development and reduced haemoglobin production. MIP-1α reduced partially developed HEL colonies and haemoglobin in developed colonies. SCF increased development, but not haemoglobin in K562 cells, with IL-3 being more effective in both. MIP-1α increased the proportion of well-developed K562 colonies but not haemoglobin. This suggests SCF, IL-3 and MIP-1α all have a role to play in early erythroid cellular development, with differing actions depending on the stage of development.  相似文献   
999.
Summary Conventional detection of islet cell antibodies is based on indirect immunofluorescence performed on frozen human pancreas sections. The number and nature of epitopes recognized by antibodies detected by such techniques are unknown. To determine the existence of heterogeneous fluorescence patterns of islet cell antibodies on pancreatic sections, we selected two sera showing a distinctive granular fluorescence. We then tested random sera from patients with Type 1 (insulin-dependent) diabetes mellitus for their ability to block ultimate binding of fluorescein isothiocyanate-labelled immunoglobulins purified from these two sera with a characteristic granular pattern. Among 102 subjects with recent-onset Type 1 diabetes, 79 had detectable anti-islet cell antibodies; 21 showed complete blockade of the binding to islets of granular fluorescein isothiocyanate-labelled immunoglobulins. The majority of these 21 patients were women carrying a DR3 non-DR4 DQB1*0201 allele, with under-representation of DRB1*0402 and 0405. Discrimination between islet cell antigenic specificities may help in identifying islet cell autoantibodies in autoimmune Type 1 diabetes.  相似文献   
1000.
To verify whether low-dose aprotinin reduces blood loss and blood product usage in patients with clopidogrel exposure within 5 days before off-pump coronary artery bypass, 51 patients with clopidogrel exposure were randomized in a double-blind fashion to receive low-dose aprotinin (25 patients), or placebo (26 patients). The baseline characteristics and number of distal anastomoses in the patients in each group were comparable. Time between the last dose of clopidogrel and start of the operation was similar in both groups, as was mean left ventricular ejection fraction. Chest tube drainage, blood product usage, and reoperation rate were significantly higher in the placebo group. In patients with unstable angina and recent clopidogrel exposure who are undergoing off-pump coronary artery bypass, intraoperative administration of low-dose aprotinin is recommended to reduce blood loss and transfusion requirements.  相似文献   
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