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71.
Strabismus is a pathology that affects approximately 4 % of the population, causing aesthetic problems reversible at any age and irreversible sensory alterations that modify the vision mechanism. The Hirschberg test is one type of examination for detecting this pathology. Computer-aided detection/diagnosis is being used with relative success to aid health professionals. Nevertheless, the routine use of high-tech devices for aiding ophthalmological diagnosis and therapy is not a reality within the subspecialty of strabismus. Thus, this work presents a methodology to aid in diagnosis of syndromic strabismus through digital imaging. Two hundred images belonging to 40 patients previously diagnosed by an specialist were tested. The method was demonstrated to be 88 % accurate in esotropias identification (ET), 100 % for exotropias (XT), 80.33 % for hypertropias (HT), and 83.33 % for hypotropias (HoT). The overall average error was 5.6Δ and 3.83Δ for horizontal and vertical deviations, respectively, against the measures presented by the specialist.  相似文献   
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BACKGROUND & AIMS: There is a long-standing interest in the identification of endothelial-specific pathways for therapeutic targeting in cirrhosis. Therefore, the aim of this study was to evaluate differences in gene expression patterns between liver endothelial cells (LECs) from control and cirrhotic rats by using microarrays. METHODS: LECs were obtained by isopycnic centrifugation. LECs gene expression was then analyzed on high-density oligonucleotide microarrays. RESULTS: Analysis of gene expression revealed that most of the differentially expressed mRNA in cirrhosis are associated with extracellular matrix remodeling, inflammation, antioxidant/stress response, and cell signaling. CONCLUSIONS: The collective expression changes observed within some functional groups of genes indicate that LECs in cirrhotic livers may contribute to lymphangiogenesis, enhancement of fibrogenesis and inflammatory processes, changes in cell-cell interaction with up-regulation of adherens junction proteins, and alterations in the intrahepatic vascular tone because of the down-regulation of genes involved in vasodilatation.  相似文献   
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OBJECTIVE: X-chromosome inactivation analysis was performed in order to assess the clonal origin of non-medullary thyroid tumours and to distinguish between multicentricity and multifocality in multiple papillary thyroid carcinoma (PTC). METHODS: One hundred and thirteen tumour samples from 31 patients with isolated PTC, 16 patients with multinodular PTC, 14 patients with follicular thyroid adenoma (FTA) and 15 patients with follicular thyroid carcinoma (FTC) were collected. The corresponding normal thyroid tissues were analysed, and in 14 cases, tumour-surrounding tissue was also studied. Genomic DNA was digested with HpaII and HhaI previous to PCR amplification of the polymorphic CAG repeat, on exon 1 of the human androgen receptor gene (HUMARA). PCR products were analysed by denaturing gel electrophoresis, silver staining and densitometric analysis. PCR products were also used to determine the number of CAG repeats of patients with isolated PTC, FTA, FTC and of 41 healthy volunteers. RESULTS: Heterozygosity for the HUMARA polymorphism was found in 64/76 (84%) cases. Lyonization of the thyroid was observed in 15/76 (20%) cases, which were excluded from clonal analysis. Except for two cases of isolated PTC, all tumour samples studied presented monoclonal X-inactivation patterns, while normal thyroid tissue was polyclonal. Monoclonal patterns were also found in 4/14 tumour-surrounding tissues. No difference was found in the length of CAG alleles between patients and controls. Of eight informative cases of multinodular PTC, three showed evidence of multicentricity and five revealed patterns consistent with multifocality. CONCLUSIONS: Both isolated and multinodular PTC as well as FTA and FTC are of monoclonal origin. Our results also suggest that approximately one-third of multiple PTC have an independent origin for the different nodules (multicentricity). Monoclonality was also found in tissues surrounding some PTC nodules. No association was found between the length of CAG alleles and thyroid malignancies.  相似文献   
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The aims of this pilot study were to verify which muscle strength tests better explain bone mineral content (BMC) of the femoral neck and lumbar spine and to develop predictive equations to estimate femoral neck and lumbar spine BMC. Twenty-nine subjects aged 56–76 years old (12 women and 17 men) participated in the study. Femoral neck and lumbar spine BMC was evaluated by Dual X-ray absorptiometry (DXA). Muscle strength measurements included maximal isometric voluntary contractions of knee extensors and flexors, vertical jump, 5-repetition maximum of the leg press (5-RMLP) and seated leg curl (5-RMLC), and handgrip strength. Women presented a moderate to strong correlation between femoral neck BMC and 5-RMLP (r = 0.819), 5-RMLC (r = 0.879), knee extensors peak torque (r = 0.699), and handgrip strength (r = 0.663), as well as between lumbar spine BMC and the 5-RMLP test (r = 0.845) and manual grip strength (r = 0.699). For females, the 5-RMLP and 5-RMLC tests most fully explained femoral neck BMC (R2 = 0.859) and the 5-RMLP test and body mass explained lumbar spine density (R2 = 0.757) for females. Men did not present correlations between BMC and strength variables. For females, the 5-RMLP and 5-RMLC variables explained the variations of femoral neck BMC, while 5-RMLP and body mass explained lumbar spine BMC. Future studies should evaluate a larger sample size and prioritize the strength tests with a greater predictive capacity.  相似文献   
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Context

Attrition is common in longitudinal observational studies in palliative care. Few studies have examined predictors of attrition.

Objectives

To identify patient characteristics at enrollment associated with attrition in palliative oncology outpatient setting.

Methods

In this longitudinal observational study, advanced cancer patients enrolled in an outpatient multicenter study were assessed at baseline and two to five weeks later. We compared baseline characteristics between patients who returned for follow-up and those who dropped out.

Results

Seven hundred forty-four patients were enrolled from Jordan, Brazil, Chile, Korea, and India. Attrition rate was 33%, with variation among countries (22%–39%; P = 0.023). In univariate analysis, baseline predictors for attrition were cognitive failure (odds ratio [OR] 1.23 per point in Memorial Delirium Assessment Scale; P < 0.01), functional status (OR 1.55 per 10-point decrease in Karnofsky Performance Status; P < 0.01), Edmonton Symptom Assessment Scale [ESAS] physical score (OR 1.03 per point; P < 0.01), ESAS emotional score (OR 1.05 per point; P < 0.01), and shorter duration between cancer diagnosis and palliative care referral in months (OR 0.89 per log; P = 0.028). In multivariate analysis, cognitive failure (OR 1.12 per point; P = 0.007), ESAS physical score (OR 1.18 per point; P = 0.027), functional status (OR 1.35 per 10-point decrease; P < 0.001), and shorter duration from cancer diagnosis (OR 0.86 per log; P = 0.01) remained independent predictors of attrition.

Conclusion

Advanced cancer patients with cognitive failure, increased physical symptoms, poorer performance status, and shorter duration from cancer diagnosis were more likely to dropout. These results have implications for research design, patient selection, and data interpretation in longitudinal observational studies.  相似文献   
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IntroductionThis study aimed to evaluate the performance of non-vitamin K antagonist oral anticoagulation (NOAC) in patients with previous stroke and non-valvular atrial fibrillation (AF) compared with left atrial appendage occlusion (LAAO) in primary and secondary stroke prevention settings.MethodsThis was a prospective, single-center, non-randomized cohort study of 302 consecutive patients with non-valvular AF and at high risk for stroke. Two treatment strategies were compared: LAAO (n=91) and long-term treatment with NOAC (n=149). The primary outcome was the composite endpoint of death, stroke and major bleeding. Propensity score and cause-of-death analyses were performed to compare outcomes.ResultsIn a mean follow-up of 13 months, there were 30 deaths (LAAO 8.8% vs. NOAC 14.8%), five strokes (LAAO 1.1% vs. NOAC 2.7%) and six major bleeds (LAAO 1.1% vs. NOAC 3.4%). There was a non-significant trend for a lower incidence of the primary endpoint in the LAAO group (11.0% vs. 20.9%; HR 0.42, 95% CI 0.17-1.05, p=0.064). Considering only secondary prevention LAAO patients (34.1% of the LAAO group), there was also a non-significant lower incidence of the primary endpoint (LAAO 6.5% vs. 20.9%; HR 0.30, 95% CI 0.07-1.39, p=0.12). While about a fifth of LAAO patients stopped antiplatelet treatment six months after device implantation due to recurrent minor bleeding, no adverse cardiovascular event or major bleeding occurred in this subset of patients.ConclusionIn this registry-based study, LAAO was a reasonable alternative to NOAC for the prevention of a composite endpoint of all-cause mortality, stroke and major bleeding in patients at high risk for stroke.  相似文献   
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