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61.
Disability glare, affecting e.g. road safety at night, may result either from intraocular light scattering or from external conditions such as fog. Measurements were made of light scattering in fog and compared with intraocular straylight data for normal eyes and eyes with simulated cataract. All measurements were made with a direct compensation flicker method. To estimate light scattering levels in fog, straylight measurements were carried in a fog chamber for different densities of fog. Density was characterized by the meteorological term visibility V and ranged from 7 to 25. Test distance for measurements in the fog was constant at 5 m. Cataract eye conditions were simulated by placing a light scattering polymer dispersed liquid crystal (PDLC) filter with scatterers of submicron size in front of the normal eye. All measurements were made using each of three broad-band color stimuli – red, green and blue (produced either with LEDs or a color CRT monitor). Differences were found in both the level and the spectral characteristics of scattering under the different conditions. The measured values of the straylight parameter, s , in artificial fog showed no noticeable spectral dependence at any visibility range. Increasing the visibility range caused an exponential decrease in the straylight. Intraocular straylight measured with the clear eye showed an increase at the red and blue ends of the spectrum as compared to the green. Straylight measured using PDLC plates with different transparency levels showed a spectral dependence which decreased with wavelength. The scattering introduced by the PDLC plate therefore failed to give a valid simulation of cataract and fog conditions for polychromatic stimuli, due to its erroneous spectral dependence. 相似文献
62.
V. Colomb 《Nutrition Clinique et Métabolisme》2003,17(4):269-275
Despite major advances in the quality of care in many other areas, the prevalence of malnutrition in hospitals is high and has not decreased over the last 20 years. Young children are especially threatened. Malnutrition is associated with an increase in morbidity and mortality in hospitalized patients, induces an increase in length of stay and thus, in hospital costs. The nutritional risk in hospitalized patients is related to the underlying disease and to the organization of feeding and nutrition in the hospitals. Moreover, most of the physicians and other professionals do not have enough knowledge in the area of nutrition. Therefore, the intervention of professionals specialized in nutrition is needed. These professionals must be well organized and coordinated. Two different kinds of nutritional support boards exist in hospitals. Nutrition advisory (steering) boards which include all categories of professionals involved in feeding and nutrition, set broad policies about patients’ meal service and nutrition, but do not envisage patients on an individual basis. By contrast, nutrition (support) teams (NT) are little clinical units (even without devoted beds), involving a small number of nutrition specialists including at least one senior physician, to which patients should be referred individually. The main objective of the NT is to set up optimum nutrition according to each individual situation, especially in case of need for artificial nutrition. The impact of NT intervention, in terms of patients’ outcome as well as financial benefits, has been shown for long. 相似文献
63.
Emanuela Taioli Simone Benhamou Christine Bouchardy Ingolf Cascorbi Nohelia Cajas-Salazar Heike Dally Kwun M Fong Jill E Larsen Loic Le Marchand Stephanie J London Angela Risch Margaret R Spitz Isabelle Stucker Brian Weinshenker Xifeng Wu Ping Yang 《Genetics in medicine》2007,9(2):67-73
Myeloperoxidase is a phase I metabolic enzyme that converts the metabolites of benzo[a]pyrene from tobacco smoke into highly reactive epoxides. A polymorphism in the promoter region of myeloperoxidase (463G-->A) has been found to be inversely associated with lung cancer; differences in the association with age and gender have been suggested. We conducted a pooled analysis of individual data from 10 studies (3688 cases and 3874 controls) from the Genetic Susceptibility to Environmental Carcinogens database. The odds ratio for lung cancer was 0.88 (95% confidence interval: 0.80-0.97) for the AG variant of myeloperoxidase G-463A polymorphism, and 0.71 (95% confidence interval: 0.57-0.88) for the AA variant after adjusting for smoking, age, gender, and ethnicity. The inverse association between lung cancer and myeloperoxidase G-463A polymorphism was equally found in males and females (odds ratio for the AA genotype 0.73 [95% confidence interval: 0.56-0.96] and 0.67 [95% confidence interval: 0.46-0.98], respectively), without differences in the association according to age in the two genders. The myeloperoxidase G-463A polymorphism was significantly protective in "ever" smokers but not in "never" smokers. Myeloperoxidase is a key enzyme in tobacco-induced carcinogenesis. 相似文献
64.
Impaired humoral immunity in X-linked lymphoproliferative disease is associated with defective IL-10 production by CD4+ T cells 下载免费PDF全文
Ma CS Hare NJ Nichols KE Dupré L Andolfi G Roncarolo MG Adelstein S Hodgkin PD Tangye SG 《The Journal of clinical investigation》2005,115(4):1049-1059
X-linked lymphoproliferative disease (XLP) is an often-fatal immunodeficiency characterized by hypogammaglobulinemia, fulminant infectious mononucleosis, and/or lymphoma. The genetic lesion in XLP, SH2D1A, encodes the adaptor protein SAP (signaling lymphocytic activation molecule-associated [SLAM-associated] protein); however, the mechanism(s) by which mutations in SH2D1A causes hypogammaglobulinemia is unknown. Our analysis of 14 XLP patients revealed normal B cell development but a marked reduction in the number of memory B cells. The few memory cells detected were IgM(+), revealing deficient isotype switching in vivo. However, XLP B cells underwent proliferation and differentiation in vitro as efficiently as control B cells, which indicates that the block in differentiation in vivo is B cell extrinsic. This possibility is supported by the finding that XLP CD4(+) T cells did not efficiently differentiate into IL-10(+) effector cells or provide optimal B cell help in vitro. Importantly, the B cell help provided by SAP-deficient CD4(+) T cells was improved by provision of exogenous IL-10 or ectopic expression of SAP, which resulted in increased IL-10 production by T cells. XLP CD4(+) T cells also failed to efficiently upregulate expression of inducible costimulator (ICOS), a potent inducer of IL-10 production by CD4(+) T cells. Thus, insufficient IL-10 production may contribute to hypogammaglobulinemia in XLP. This finding suggests new strategies for treating this immunodeficiency. 相似文献
65.
FOXC1 haploinsufficiency due to 6p25 deletion in a patient with rapidly progressing aortic valve disease 下载免费PDF全文
66.
Pierre Lantelme Hélène Eltchaninoff Muriel Rabilloud Géraud Souteyrand Marion Dupré Marco Spaziano Marc Bonnet Clément Becle Benjamin Riche Eric Durand Erik Bouvier Jean-Nicolas Dacher Pierre-Yves Courand Lucie Cassagnes Eduardo E. Dávila Serrano Pascal Motreff Loic Boussel Thierry Lefèvre Brahim Harbaoui 《JACC: Cardiovascular Imaging》2019,12(1):123-132
Objectives
The aim of this study was to develop a new scoring system based on thoracic aortic calcification (TAC) to predict 1-year cardiovascular and all-cause mortality.Background
A calcified aorta is often associated with poor prognosis after transcatheter aortic valve replacement (TAVR). A risk score encompassing aortic calcification may be valuable in identifying poor TAVR responders.Methods
The C4CAPRI (4 Cities for Assessing CAlcification PRognostic Impact) multicenter study included a training cohort (1,425 patients treated using TAVR between 2010 and 2014) and a contemporary test cohort (311 patients treated in 2015). TAC was measured by computed tomography pre-TAVR. CAPRI risk scores were based on the linear predictors of Cox models including TAC in addition to comorbidities and demographic, atherosclerotic disease and cardiac function factors. CAPRI scores were constructed and tested in 2 independent cohorts.Results
Cardiovascular and all-cause mortality at 1 year was 13.0% and 17.9%, respectively, in the training cohort and 8.2% and 11.8% in the test cohort. The inclusion of TAC in the model improved prediction: 1-cm3 increase in TAC was associated with a 6% increase in cardiovascular mortality and a 4% increase in all-cause mortality. The predicted and observed survival probabilities were highly correlated (slopes >0.9 for both cardiovascular and all-cause mortality). The model’s predictive power was fair (AUC 68% [95% confidence interval [CI]: 64% to 72%]) for both cardiovascular and all-cause mortality. The model performed similarly in the training and test cohorts.Conclusions
The CAPRI score, which combines the TAC variable with classical prognostic factors, is predictive of 1-year cardiovascular and all-cause mortality. Its predictive performance was confirmed in an independent contemporary cohort. CAPRI scores are highly relevant to current practice and strengthen the evidence base for decision making in valvular interventions. Its routine use may help prevent futile procedures. 相似文献67.
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70.
Virginie Colomb 《Nutrition Clinique et Métabolisme》2001,15(4):325
Cancer is associated with a high risk of malnutrition in children. This risk is different from one tumor to another, at the time of diagnosis and at any time of the disease course. Numerous tumor-related and treatment-related factors are involved. High dose-chemotherapy, with its specific side effects is particularly deleterious. Growth curves are of major interest for the long-term follow up of the nutritional status in children. The systematic use of nutritional risk scores is recommended, in order to improve prevention and early treatment of malnutrition. Nutritional supplies should meet the high protein and energy needs associated with cancer and its treatments. Oral and tube-feeding should be used preferably, according to digestive function. Peripheral parenteral nutrition may serve only as a complementary, short-term nutritional support. Central lines are required for all total and/or long term parenteral nutrition periods. Whatever the nutritional support, it can help to fulfil chemotherapy programmes, with benefit on remission duration and survival. 相似文献