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1.
This study estimated the effects of changing multiple levels and combinations of nutrition information format, load, expression, and order on consumers' perceptions of label usefulness in purchase decisions using adaptive conjoint analysis. A shopping mall intercept survey, which was administered by a marketing research firm, assessed consumer preferences for 12 label alternatives produced on Campbell's soup cans to portray nutrition information realistically; 252 of 258 respondents completed the computer interactive interview. Consumers significantly preferred the bar graph format to the bar graph/nutrient density and traditional label formats. Consumers considered the bar graph/nutrient density format to be as useful as the traditional label format. There was a highly significant difference among the three levels of information load; the most information load was preferred regardless of nutrient importance. Consumers significantly preferred nutrition information stated in absolute numbers and percentages vs in absolute numbers only in traditional, or in percentages only expressions. There was a significant difference between consumer preferences for the two types of information order. The findings indicate that consumers clearly preferred the nutrition label that displayed all nutrient values using a bar graph format, offered the most information load, and expressed nutrient values using both absolute numbers and percentages. Consumers also preferred nutrition information rearranged in an order that grouped nutrients that should be consumed in adequate amounts on the top, calories in the middle, and nutrients that should be consumed in lesser amounts on the bottom of the label.  相似文献   
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This study aimed to assess the ability of global and local systolic parameters measured with gated blood-pool SPECT (GBPS) to diagnose and characterize the severity of diffuse or localized arrhythmogenic right ventricular dysplasia (ARVD). METHODS: Fifty-nine subjects with symptomatic ventricular arrhythmias were prospectively included in the study. With the International Society and Federation of Cardiology criteria for ARVD as a gold standard, these subjects were classified as subjects without ARVD (21 control subjects) and patients with localized ARVD (16 patients) or diffuse ARVD (22 patients). Right ventricular volumes, right ventricular ejection fractions (EF), the SD of local EF (sigma-EF), and the SD of the local times of end systole (sigma-TES) were computed from GBPS data and compared among the groups in the study population. RESULTS: sigma-EF did not differ between control subjects and patients with diffuse or localized ARVD. Right ventricular EF and volumes differed between patients with diffuse ARVD and control subjects, with similar areas under the receiver-operating-characteristic curves, but right ventricular EF and volumes failed to differentiate patients with localized ARVD. In contrast, sigma-TES differed between patients with diffuse or localized ARVD and control subjects. Regression analysis showed that the systolic parameter most strongly associated with the diagnosis of ARVD was sigma-TES. The probabilities of a randomly chosen patient in the diffuse ARVD group and of a randomly chosen patient in the localized ARVD group having sigma-TES values greater than that of a randomly chosen control subject were 98.5% and 96.7%, respectively. For the diagnosis of localized ARVD, a threshold of 80 ms for sigma-TES corresponded to sensitivity, specificity, and positive and negative predictive values of 100%, 81%, 80%, and 100%, respectively. CONCLUSION: With GBPS, both diffuse ARVD and localized ARVD can be accurately diagnosed by computing sigma-TES for all of the pixels on the surface of the right ventricle.  相似文献   
3.
The effects of OSM on proliferation and differentiation of osteosarcoma and nontransformed osteoblasts were analyzed. OSM downregulates osteoblast markers but induces the glial fibrillary acidic protein by the combined activation of PKCdelta and STAT3, offering new lines of therapeutic investigations. INTRODUCTION: Oncostatin M (OSM) is a multifunctional cytokine of the interleukin-6 family implicated in embryonic development, differentiation, inflammation, and regeneration of various tissues, mainly the liver, bone, and the central nervous and hematopoietic systems. One particularity of OSM relies on its growth inhibitory and pro-differentiating effects on a variety of tumor cell lines such as melanoma, providing arguments for a therapeutic application of OSM. The objective of this study was to analyze the effects of OSM on osteosarcoma cell lines proliferation and differentiation. MATERIALS AND METHODS: Proliferation was analyzed by 3H thymidine incorporation. Differentiation was analyzed by semiquantitative RT-PCR and immunocytochemistry for various markers. Alizarin red S staining was used to evaluate bone nodule formation. Morphological changes were studied by confocal and electron microscopy. Western blotting, kinases inhibitors, and dominant negative STAT3 were used to identified the signaling pathways implicated. RESULTS: OSM inhibits the growth of rat osteosarcoma cell lines as well as normal osteoblasts, in correlation with induction of the cyclin-dependent kinases inhibitor p21WAF1. However, OSM reduces osteoblast markers such as alkaline phosphatase, osteocalcin, and bone sialoprotein, leading to strong inhibition of mineralized nodule formation. This inhibitory effect is restricted to mature osteoblasts and differentiated osteosarcoma because OSM effectively stimulates osteoblast markers and bone nodule formation in early, but not late, bone marrow mesenchymal stem cell (BMSC) cultures. In osteosarcoma cells or BMSC, OSM induces expression of the glial fibrillary acidic protein (GFAP) as well as morphological and ultrastructural changes, for example, elongated shape and bundles of microfilaments in cell processes. Rottlerin (PKCdelta inhibitor), and to a lesser degree UO126 (MEK/ERK inhibitor), prevents the loss of osteoblastic markers by OSM, whereas dominant negative STAT3 prevents GFAP induction. CONCLUSIONS: These results highlight the particular gene expression profile of OSM-treated osteosarcoma cells and BMSCs, suggesting either a osteocytic or a glial-like phenotype. Together with the implication of PKCdelta, ERK1/2, and STAT3, these results offer new lines of investigations for neural cell transplantation and osteosarcoma therapy.  相似文献   
4.
A 26-year-old patient presented with acute chiasmal syndrome. Computerized Tomography and Magnetic Resonance Imaging demonstrated an intrachiasmal hematoma which was evacuated via a right subfrontal approach. Histological examination revealed an arteriovenous malformation. In 21 similar cases in the literature, surgery generally resulted in the improvement of ophthalmological signs. In 3/4 of the cases, histology identified a subjacent lesion (arteriovenous malformation, cavernoma, venous angioma, glioma).  相似文献   
5.
The adaptation rule of Vector Quantization algorithms, and consequently the convergence of the generated sequence, depends on the existence and properties of a function called the energy function, defined on a topological manifold. Our aim is to investigate the conditions of existence of such a function for a class of algorithms including the well-known 'K-means' and 'Self-Organizing Map' algorithms. The results presented here extend several previous studies and show that the energy function is not always a potential but at least the uniform limit of a series of potential functions which we call a pseudo-potential. It also shows that a large number of existing vector quantization algorithms developed by the Artificial Neural Networks community fall into this class. The framework we define opens the way to studying the convergence of all the corresponding adaptation rules at once, and a theorem gives promising insights in that direction.  相似文献   
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Ohne Zusammenfassung
Nouveaux livres
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BACKGROUND: The complaint of chronic hair loss frequently affects female subjects and there is little or no objective technology available in the general dermatology or even in the hair clinics to guide the observer in the management of the patient. The purpose of this report is to share the results of refined hair growth measurements that were collected in 92 female subjects complaining about hair loss. METHODS: Clinically they were classified as having a patterned hair loss according to Ludwig (L; n=50), diffuse hair loss (D; n=13) or no visible hair loss but complaining of hair shedding (N; n=29). Two scalp sites on the top of the head and one occipital site were investigated after clipping by close-up photography before and after a hair dye (contrast enhancement, CE). Forty-eight hours later a new photograph was taken after CE in view of phototrichogram analysis (CE-PTG). Finally a last hair clip was performed 30 days later and hair thickness and length determined for linear growth measurements (LHGR). RESULTS: Herein we confirm that the top of the head shows usually a higher hair density than occipital sites, a physiological observation that applies both to men and women. From the technological perspective, we also document that CE improves hair detection in all sites. Interestingly, in affected patients (L and D) the relative increase of hair counts after CE was much higher (range +22.4% to +28.3%) compared with apparently unaffected females (N; range +8.2% to +9.7%). This increase in hair counts was only due in part to the presence of less pigmented thinning hair (thickness less than 40 microm). Such thin hairs were found in statistically significantly higher proportions in younger patients with mildly severe (grade I) patterned alopecia (Ludwig: L). In other patients with hair loss and in more severe forms of patterned alopecia - especially in older patients - the thin hair is not detected in abnormal proportions. In all sites slower growth rates and decreased anagen percentages indicate a defective hair replacement programme distinguishing L patterns from diffuse hair loss and from apparently unaffected patients complaining of chronic hair loss. Globally, we also noted that increasing age is associated with significant regression of scalp hair (decreased hair counts, thinner hair and slower LHGR). CONCLUSION: On the basis of the present data together with female data from the literature and our own studies in male subjects, we suggest a three-step mechanism leading to hair loss 1.Shortening of growth phase the hair cycle with maintained thick hair, i.e. more frequent hair cycling that leads to more hair shedding. 2.Intermittent production of short thin hair, i.e. morphological evidence of miniaturisation. 3.Very occasional or almost no hair production, i.e. dormant follicles or irreversible follicular atrophy. Depending on the genetic background, hormonal microenvironment in the scalp and conditioning of individual hair follicle bio-responses, female and male patterned hair loss may end up into different phenotypes.  相似文献   
9.
Charcot-Marie-Tooth type 1A disease is an inherited sensorimotor neuropathy that is most often associated with a duplication of chromosome 17p11.2. This region contains the gene of the peripheral myelin protein 22 (PMP22), which is responsible by a gene dosage effect for the Charcot-Marie-Tooth type 1A phenotype with 17p11.2 duplication. We performed a clinical, electrophysiological, and genetic study of a consanguinous Charcot-marie-Tooth type 1A family with 4 affected siblings, 3 of whom were homozygous for the 17p11.2 duplication, the other a heterozygote. Comparison of phenotypes showed that the severity of the disease was more severely affected than the heterozygous sibling who was pausiymptomatic. These results suggest that the severity of the disease is not determined solely by the number of copies of the PMP22 gene.  相似文献   
10.
Summary Obturator hernias comprise a rare group of abdominal hernias. They are often diagnosed when the small bowel has become obstructed and the patients are operated on without the causes of the obstruction being known. Although many techniques for closure of the defect are available, there is no agreement at the present time as to which is the procedure of choice.  相似文献   
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