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991.
992.

Objective

Recognizing the need for a consensus tool to measure social class in health sciences, in 1995 the Spanish Society of Epidemiology (Sociedad Española de Epidemiología [SEE]) made a proposal for such a measure. The aim of this article was to explore the bibliometric impact of the SEE's proposal.

Methods

Articles citing the SEE's report and those citing articles published as a result of the report were identified using Google Scholar and Scopus. The information extracted from these articles consisted of year, nationality and impact factor of the journal, self-citation, information source, subject area, city of the first author, type of publication, study design, use of social class as a variable, number of social class categories, and the use of education or occupation to determine social class.

Results

The number of citations progressively increased. Citations also showed heterogeneity in the subject. Generally, citations were found in original articles and articles with a cross sectional design, were published in journals with impact factor and were by researchers working in Barcelona or Madrid.

Conclusions

The SEE's proposal has proved to be an increasingly useful tool, applicable in different contexts. As suggested by the SEE, this proposal may need to be updated.  相似文献   
993.
Post-operative atrial fibrillation (AF) is a common and serious complication in patients undergoing aortic valve replacement (AVR). Speckle tracking echocardiography (STE) has recently enabled the quantification of longitudinal myocardial left atrial (LA) deformation dynamics. Our aim was to investigate LA preoperative mechanical function in patients undergoing AVR for aortic stenosis using STE and determine predictors of post-operative AF. 76 patients with aortic stenosis in sinus rhythm, undergoing AVR, were prospectively enrolled. Conventional echocardiographic parameters, and peak atrial longitudinal strain (PALS) were measured in all subjects the day before surgery. PALS values were obtained by averaging all segments in the 4- and 2-chamber views (global PALS). All patients received biological valve prostheses and a standard postoperative care. Postoperative AF occurred in 15 patients (19.7 %). On univariate analysis among all clinical and echocardiographic variables, global PALS showed the highest diagnostic accuracy (HR 6.55 p < 0.0001; AUC of 0.89) with a cut-off value <16.9 %, having sensitivity and specificity of 86 and 91 %, respectively, in predicting postoperative AF. LA volume indexed and E/e’ ratio had lower diagnostic accuracy (AUC 0.76 and 0.51, respectively). On multivariate analysis global PALS remains a significant predictor of postoperative AF (p < 0.0001). STE analysis of LA myocardial deformation is considered a promising tool for the evaluation of LA subclinical dysfunction in patients undergoing AVR, giving a potentially better risk stratification for the occurrence of postoperative AF.  相似文献   
994.

Introduction

The safety of arterial hyperoxia is under increasing scrutiny. We performed a systematic review of the literature to determine whether any association exists between arterial hyperoxia and mortality in critically ill patient subsets.

Methods

Medline, Thomson Reuters Web of Science and Scopus databases were searched from inception to June 2014. Observational or interventional studies evaluating the relationship between hyperoxia (defined as a supranormal arterial O2 tension) and mortality in adult intensive care unit (ICU) patients were included. Studies primarily involving patients with exacerbations of chronic pulmonary disease, acute lung injury and perioperative administration were excluded. Adjusted odds ratio (OR) of patients exposed versus those not exposed to hyperoxia were extracted, if available. Alternatively, unadjusted outcome data were recorded. Data on patients, study characteristics and the criteria used for defining hyperoxia exposure were also extracted. Random-effects models were used for quantitative synthesis of the data, with a primary outcome of hospital mortality.

Results

In total 17 studies (16 observational, 1 prospective before-after) were identified in different patient categories: mechanically ventilated ICU (number of studies (k) = 4, number of participants (n) = 189,143), post-cardiac arrest (k = 6, n = 19,144), stroke (k = 2, n = 5,537), and traumatic brain injury (k = 5, n = 7,488). Different criteria were used to define hyperoxia in terms of PaO2 value (first, highest, worst, mean), time of assessment and predetermined cutoffs. Data from studies on ICU patients were not pooled because of extreme heterogeneity (inconsistency (I2) 96.73%). Hyperoxia was associated with increased mortality in post-cardiac arrest patients (OR = 1.42 (1.04 to 1.92) I2 67.73%) stroke (OR = 1.23 (1.06 to 1.43) I2 0%) and traumatic brain injury (OR = 1.41 (1.03 to 1.94) I2 64.54%). However, these results are limited by significant heterogeneity between studies.

Conclusions

Hyperoxia may be associated with increased mortality in patients with stroke, traumatic brain injury and those resuscitated from cardiac arrest. However, these results are limited by the high heterogeneity of the included studies.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-014-0711-x) contains supplementary material, which is available to authorized users.  相似文献   
995.
996.
997.
Autoimmune reactions are often associated with alcoholic liver disease; however, the mechanisms responsible are largely unknown. This study investigates the potential role of the immune response against hydroxyethyl free radical (HER)-derived antigens and of polymorphisms in immunoregulatory genes in the development of anti-cytochrome P4502E1 (CYP2E1) autoantibodies in alcohol abusers. Immunoglobulin G (IgG) recognizing human CYP2E1 and HER-derived epitopes were measured by microplate immunosorbent assay in the sera of 90 patients with alcoholic fibrosis/cirrhosis (ALD), 37 heavy drinkers without liver disease or steatosis only (HD), and 59 healthy subjects. Single nucleotide polymorphisms in the interleukin 10 (IL-10) promoter and in exon 1 of the cytotoxic T-lymphocyte antigen-4 (CTLA-4) gene were genotyped by polymerase chain reaction-restriction fragment length polymorphism analysis. The titers and frequency of anti-CYP2E1 autoantibodies were significantly higher in ALD than in HD subjects or controls. ALD patients with anti-HER IgG had higher titers and a 4-fold increased risk (OR: 4.4 [1.8-10.9]) of developing anti-CYP2E1 autoantibodies than subjects without anti-HER antibodies. The mutant CTLA-4 G allele, but not the IL-10 polymorphism, was associated with an enhanced risk of developing anti-CYP2E1 IgG (OR: 3.8 [1.4-10.3]). CTLA-4 polymorphism did not influence antibody formation toward HER-antigens. ALD patients with concomitant anti-HER IgG and the CTLA-4 G allele had a 22-fold higher (OR: 22.9 [4.2-125.6]) risk of developing anti-CYP2E1 autoreactivity than subjects negative for these factors. In conclusion, antigenic stimulation by HER-modified CYP2E1 combined with an impaired control of T-cell proliferation by CTLA-4 mutation promotes the development of anti-CYP2E1 autoantibodies that might contribute to alcohol-induced liver injury.  相似文献   
998.
ObjectiveBaricitinib seems a promising therapy for COVID-19. To fully-investigate its effects, we in-vitro evaluated the impact of baricitinib on the SARS-CoV-2-specific-response using the whole-blood platform.MethodsWe evaluated baricitinib effect on the IFN-γ-release and on a panel of soluble factors by multiplex-technology after stimulating whole-blood from 39 COVID-19 patients with SARS-CoV-2 antigens. Staphylococcal Enterotoxin B (SEB) antigen was used as a positive control.ResultsIn-vitro exogenous addition of baricitinib significantly decreased IFN-γ response to spike- (median: 0.21, IQR: 0.01–1; spike+baricitinib 1000 nM median: 0.05, IQR: 0–0.18; p < 0.0001) and to the remainder-antigens (median: 0.08 IQR: 0–0.55; remainder-antigens+baricitinib 1000 nM median: 0.03, IQR: 0–0.14; p = 0.0013). Moreover, baricitinib significantly decreased SEB-induced response (median: 12.52, IQR: 9.7–15.2; SEB+baricitinib 1000 nM median: 8, IQR: 1.44–12.16; p < 0.0001). Baricitinib did modulate other soluble factors besides IFN-γ, significantly decreasing the spike-specific-response mediated by IL-17, IL-1β, IL-6, TNF-α, IL-4, IL-13, IL-1ra, IL-10, GM-CSF, FGF, IP-10, MCP-1, MIP-1β (p ≤ 0.0156). The baricitinib-decreased SARS-CoV-2-specific-response was observed mainly in mild/moderate COVID-19 and in those with lymphocyte count ≥1 × 103/µl.ConclusionsExogenous addition of baricitinib decreases the in-vitro SARS-CoV-2-specific response in COVID-19 patients using a whole-blood platform. These results are the first to show the effects of this therapy on the immune-specific viral response.  相似文献   
999.
PURPOSE Reports of the relationship between length of delay before diagnosis of rectal cancer and stage of the disease have been mixed. The present study documented the magnitude and medical ramifications of delay in diagnosing rectal cancer.METHODS One hundred twenty patients who had been recently diagnosed with rectal cancer provided information regarding history of symptoms and initial perceptions of those symptoms. Patients also estimated the time elapsed from onset of symptoms until their first consultation with a physician, as well as time elapsed from consultation until the diagnosis of rectal cancer was made. Stage information was gathered from patient charts.RESULTS For 106 of the patients, the first sign of rectal cancer was in the form of symptoms, and the most common first symptom was rectal bleeding. For the remaining 14 patients, their cancer was first discovered through routine examination. Over 75 percent of patients with symptoms did not initially believe that they were caused by cancer or any other serious problem, and over 50 percent attributed their symptoms to hemorrhoids. There was a clear trend, albeit statistically nonsignificant, toward worsening disease with longer delays. Median delay times in weeks were Stage I (10.0 weeks), Stage II (14.0 weeks), Stage III (18.5 weeks), and Stage IV (26.0 weeks).CONCLUSIONS Delayed diagnosis for rectal cancer remains a significant problem, with instances of delay attributable to both patient and physician. Delayed diagnosis can result in more serious disease and, when attributable to the physician, can result in damaged trust and sometimes legal action.Supported by the Alvin J. Siteman Cancer Center, National Cancer Institute Grant No. 1R03 CA84845 01, and The American Society of Colon and Rectal Surgeons (LPG 073).Reprints are not available.  相似文献   
1000.
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