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641.
A case of anaplastic carcinoma of the thyroid observed in a 72-year-old female patient, admitted with previous diagnosis of Riedel's thyroiditis, is reported. Clinicopathologic features and management of this rare neoplasm are discussed and Literature is reviewed. Anaplastic cancer is a locally and systemically aggressive histologic type, occurring more frequently in older patients and in those with a history of benign and/or malignant thyroid disease. Because long-term survival was seen most commonly in well-localized anaplastic tumors, a more aggressive approach to thyroid lesions, especially in the elderly, may be warranted to improve early diagnosis and effectiveness of therapy of this nearly always lethal neoplasm. Although patients can rarely be cured, efforts should be made to control the disease locally by combined treatment including surgery and radiochemotherapy, which is found to be, at times, a national palliative therapeutic approach despite patient's advanced age.  相似文献   
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Evaluation of performance using DEA requires models consistent with the underlying technology. There have been a number of models proposed for analyzing performance in the presence of non-discretionary inputs. Banker and Morey (Operations Research 34 (1986) 513–521) provided the first DEA model to measure technical efficiency. Other single- and multiple-stage models that incorporate DEA have been developed. This paper discusses the various approaches and provides a simulation analysis to compare the relative performance of each.  相似文献   
645.
Two competing approaches for the measurement of efficiency are the stochastic frontier model and data envelopment analysis (DEA). Previous research has established that the two models applied to cross‐sectional data are both adversely affected by measurement error. While the cross‐sectional stochastic frontier model does not effectively handle statistical noise, panel data models do. This is true because additional information from multiple time periods is incorporated into the estimation. A panel data DEA model that uses averaged data has been shown to effectively smooth out measurement error. In this paper, we compare the panel data models using simulated data.  相似文献   
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Paracetamol/Eudragit RS, paracetamol/ethylcellulose, and paracetamol/cellulose acetate pellets of different drug/polymer ratios (w/w) were prepared by the dissolution/solvent evaporation technique. These pellets were then characterized by particle size distribution analysis, ultraviolet (UV) spectroscopy, differential thermal analysis, and scanning electron microscopy (SEM). Hard gelatin capsules were filled with each particle size fraction of these pellets, and in vitro dissolution studies were performed to verify the capability of each series of pellets to control drug release. Pellets were spherical, presented a polynucleated microcapsule structure, and under certain experimental conditions, the yield of the preparation process reached very high values. The dissolution studies pointed out the slow paracetamol release from these pellets.  相似文献   
648.
We present in this work a study of the linear kink effect (LKE) occurrence in partially depleted (PD) SOI nMOSFETs with thin gate oxide. The experimental LKE dependence on the channel length, channel width and drain voltage are reported as well as the impact of various parameters on the second peak has been studied by two-dimensional numerical simulations, namely, the gate current level, the carrier lifetime, the increase of the body potential, the threshold voltage variation and AC analysis. Three-dimensional simulations were also performed in order to evaluate the LKE dependence on the channel width.  相似文献   
649.
Acute lymphoblastic leukemia type B (B-ALL) is the most common kind of pediatric leukemia, characterized by the clonal proliferation of type B lymphoid stem cells. Important progress in ALL treatments led to improvements in long-term survival; nevertheless, many adverse long-term consequences still concern the medical community. Molecular and cellular target therapies, together with immunotherapy, are promising strategies to overcome these concerns. Cannabinoids, enzymes involved in their metabolism, and cannabinoid receptors type 1 (CB1) and type 2 (CB2) constitute the endocannabinoid system, involved in inflammation, immune response, and cancer. CB2 receptor stimulation exerts anti-proliferative and anti-invasive effects in many tumors. In this study, we evaluated the effects of CB2 stimulation on B-ALL cell lines, SUP-B15, by RNA sequencing, Western blotting, and ELISA. We observe a lower expression of CB2 in SUP-B15 cells compared to lymphocytes from healthy subjects, hypothesizing its involvement in B-ALL pathogenesis. CB2 stimulation reduces the expression of CD9, SEC61G, TBX21, and TMSB4X genes involved in tumor growth and progression, and also negatively affects downstream intracellular pathways. Our findings suggest an antitumor role of CB2 stimulation in B-ALL, and highlight a functional correlation between CB2 receptors and specific anti-tumoral pathways, even though further investigations are needed.  相似文献   
650.
Alcohol use is a contributor in the premature deaths of approximately 3 million people annually. Among the risk factors for alcohol misuse is circadian rhythm disruption; however, this connection remains poorly understood. Inhibition of the circadian nuclear receptor REV-ERBα is known to disrupt molecular feedback loops integral to daily oscillations, and impact diurnal fluctuations in the expression of proteins required for reward-related neurotransmission. However, the role of REV-ERBα in alcohol and substance use-related phenotypes is unknown. Herein, we used a Rev-erbα knockout mouse line and ethanol two-bottle choice preference testing to show that disruption of Rev-erbα reduces ethanol preference in male and female mice. Rev-erbα null mice showed the lowest ethanol preference in a two-bottle choice test across all genotypes, whereas there were no ethanol preference differences between heterozygotes and wildtypes. In a separate experiment, alcohol-consuming wildtype C57Bl/6N mice were administered the REV-ERBα/β inhibitor SR8278 (25 mg/kg or 50 mg/kg) for 7 days and alcohol preference was evaluated daily. No differences in alcohol preference were observed between the treatment and vehicle groups. Our data provides evidence that genetic variation in REV-ERBα may contribute to differences in alcohol drinking.  相似文献   
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