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Aims and objectives.  To perform the semantic validation and to evaluate the reliability and the presence of ceiling and floor effects of the Cardiac Patients Learning Needs Inventory in Portuguese patients with coronary artery disease. Background.  Information should be selected based on what patients know and need to learn, which means that the teaching process should be based on each person’s needs. The Cardiac Patients Learning Needs Inventory is aimed at identifying the cardiac patients’ individual learning needs. Design.  Methodological research design. Methods.  Two hundred patients hospitalised at the coronary intensive care unit or at the cardiothoracic surgery unit of a public hospital in Lisbon answered the adapted version of the Cardiac Patients Learning Needs Inventory. Internal consistency was estimated based on Cronbach’s alpha. Scores above 0·50 were considered acceptable. Stability was measured through test–retest and calculated using student’s t test. Significance was set at 0·05. Results.  Patients’ mean age was 65 years (SD = 11·8), and most were men (152; 76%). Cronbach’s alpha for the total scale was high in the first and second measurement (0·91), and for seven domains, it was acceptable in the first and second measurement (range from 0·50–0·89). No statistically significant difference was found between mean scores on the first and second measurement. Lower diversity was observed in the answers, most of which ranged between important and very important (ceiling‐effect). Conclusion.  The adapted version for use in Portugal maintained the conceptual, semantic and idiomatic equivalences of the original version and showed adequate reliability. Relevance to clinical practices.  Owing to the lack of validated instruments translated into Portuguese, to measure cardiac patients’ learning needs, this study entails important clinical and theoretical implications.  相似文献   
547.

Background

Studies show that women with low vitamin D levels have an increased risk of breast cancer (BC) incidence and mortality, but there is a lack of research examining vitamin D levels and prognostic variables in BC patients. The aim of this study is to examine 25-OH vitamin D levels between BC cases and controls and by prognostic indicators among BC cases.

Methods

25-OH vitamin D levels were collected from 194 women who underwent BC surgery and 194 cancer-free (CF) controls at the University of Rochester between January 2009 and October 2010. Mean 25-OH vitamin D levels and odds ratios (OR) were calculated by case/control status for the overall cohort and by prognostic indicators (invasiveness, ER status, triple-negative status, Oncotype DX score, molecular phenotype) for BC cases.

Results

BC cases had significantly lower 25-OH vitamin D levels than CF controls (BC: 32.7?ng/mL vs. CF: 37.4?ng/mL; P?=?.02). In case-series analyses, women with suboptimal 25-OH vitamin D concentrations (<32?ng/mL) had significantly higher odds of having ER? (OR?=?2.59, 95% confidence interval [95% CI]?=?1.08?C6.23) and triple-negative cancer (OR?=?3.15, 95% CI?=?1.05?C9.49) than those with optimal 25-OH D concentrations. Women with basal-like phenotype had lower 25-OH vitamin D levels than women luminal A phenotype (basal-like: 24.2?ng/mL vs. luminal A: 32.8?ng/mL; P?=?0.04).

Conclusions

BC patients with a more aggressive molecular phenotype (basal-like) and worse prognostic indicators (ER? and triple-negative) had lower mean 25-OH vitamin D levels. Further research is needed to elucidate the biological relationship between vitamin D and BC progression.  相似文献   
548.
In this study, three different akermanite:poly‐?‐caprolactone (PCL) composite scaffolds (wt%: 75:25, 50:50, 25:75) were characterized in terms of structure, compression strength, degradation rate and in vitro biocompatibility to human adipose‐derived stem cells (hASC). Pure ceramic scaffolds [CellCeramTM, custom‐made, 40:60 wt%; β‐tricalcium phosphate (β‐TCP):hydroxyapatite (HA); and akermanite] and PCL scaffolds served as experimental controls. Compared to ceramic scaffolds, the authors hypothesized that optimal akermanite:PCL composites would have improved compression strength and comparable biocompatibility to hASC. Electron microscopy analysis revealed that PCL‐containing scaffolds had the highest porosity but CellCeramTM had the greatest pore size. In general, compression strength in PCL‐containing scaffolds was greater than in ceramic scaffolds. PCL‐containing scaffolds were also more stable in culture than ceramic scaffolds. Nonetheless, mass losses after 21 days were observed in all scaffold types. Reduced hASC metabolic activity and increased cell detachment were observed after acute exposure to akermanite:PCL extracts (wt%: 75:25, 50:50). Among the PCL‐containing scaffolds, hASC cultured for 21 days on akermanite:PCL (wt%: 75:25) discs displayed the highest viability, increased expression of osteogenic markers (alkaline phosphatase and osteocalcin) and lowest IL‐6 expression. Together, the results indicate that akermanite:PCL composites may have appropriate mechanical and biocompatibility properties for use as bone tissue scaffolds. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
549.
The recently identified Kaposi's sarcoma-associated herpesvirus (KSHV), also known as human herpesvirus 8 (HHV-8), has been found to be consistently associated with an unusual subset of acquired immunodeficiency syndrome-related lymphomas, the so-called body cavity- based lymphomas (BCBL) or primary effusion lymphomas (PEL). These lymphomas are characterized by a unique spectrum of morphologic and molecular characteristics, and grow as lymphomatous effusions without an identifiable contiguous tumor mass. Until now, efforts to delineate the role of KSHV in the pathogenesis of PELs have been hampered by the lack of appropriate model systems and the concomitant presence of Epstein-Barr virus (EBV) in nearly all cases examined, and in all previously established cell lines. We now report the establishment and characterization of a novel PEL cell line, BC-3, which is KSHV+ by polymerase chain reaction (PCR) but EBV- as assessed by a variety of methods including PCR for EBER, EBNA-2, and EBNA-3C. This cell line was established from a lymphomatous effusion obtained from an HIV- patient, and has immunophenotypic and molecular features consistent with the diagnosis of PEL, including an indeterminate immunophenotype with a B- cell immunogenotype and lack of c-myc proto-oncogene rearrangements. Pulsed-field gel electrophoresis shows an intact KSHV genome of about 170 kb both in the cell line and in the viral isolate, whereas herpesvirus-like capsids are visible by electron microscopy. Consequently, the BC-3 cell line represents an invaluable tool as a source of KSHV, for both the evaluation of the pathogenic potential of this virus and the mechanistic characterization of its role in the development of Kaposi's sarcoma and malignant lymphoma.  相似文献   
550.
AIM:To assess the vitamin A status of patients with Crohn’s disease(CD) by evaluating serum retinol levels and the relative dose response(RDR) test(liver retinol stores).METHODS:Vitamin A nutritional status was measured by serum retinol obtained by high performance liquid chromatography and the RDR test for evaluation of the hepatic stores.Body composition was performed by densitometry by dual-energy X-ray absorptiometry.Vitamin A dietary intake was assessed from a semiquantitative food frequency questionnaire.RESULTS:This study included 38 CD patients and 33 controls.Low serum retinol concentrations were detected in 29% of CD patients vs 15% in controls(P < 0.005).The RDR test was positive in 37% of CD patients vs 12% in controls,which indicated inadequate hepatic vitamin A stores(P < 0.005).Individuals with hypovitaminosis A had lower BMI and body fat compared with those without this deficiency.There was no association between vitamin A deficiency and its dietary intake,ileal location,presence of disease activity and prior bowel resections.CONCLUSION:Patients with CD have higher prevalence of vitamin A deficiency,as assessed by two independent methods.  相似文献   
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