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We have established two cell lines, PER-452 and PER-453, from an 8-month-old girl with an extensive pineoblastoma. Characterization of these lines revealed that the proto-oncogenes MYC and MYCN were not amplified, but both cell lines showed MYCN expression comparable to a cell line with 200-fold MYCN amplification. Both cell lines contained an i( 17q). These results support the concept that pineoblastomas belong to a larger group of primitive neuroectodermal tumors of the central nervous system. These two cell lines provide a unique opportunity to investigate the molecular genetic mechanisms underlying these neoplasms further. Genes Chrom Cancer 9:129-135 (1994).© 1994 Wiley-Liss, Inc.  相似文献   
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Hypoglycemia limits optimal glycemic management of patients with type 1 diabetes mellitus (T1DM). Fear of hypoglycemia (FoH) is a significant psychosocial consequence that negatively impacts the willingness of T1DM patients to engage in and profit from the health benefits of regular physical activity (e.g., cardiometabolic health, improved body composition, cardiovascular fitness, quality of life). Technological advances, improved insulin regimens, and a better understanding of the physiology of various types of exercise could help ameliorate FoH. This narrative review summarizes the available literature on FoH in children and adults and tools to avoid it.  相似文献   
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The structure–property relationship of dielectric elastomers, as well as the methods of improving the control of this relationship, has been widely studied over the last few years, including in some of our previous works. In this paper, we study the control, improvement, and correlation, for a significant range of temperatures, of the mechanical and dielectric properties of polystyrene-b-(ethylene-co-butylene)-b-styrene (SEBS) and maleic-anhydride-grafted SEBS (SEBS-MA) by using graphite (G) as filler in various concentrations. The aim is to analyze the suitability of these composites for converting electrical energy into mechanical energy or vice versa. The dielectric spectroscopy analysis performed in the frequency range of 10 to 1 MHz and at temperatures between 27 and 77 °C emphasized an exponential increase in real permittivity with G concentration, a low level of dielectric losses (≈10−3), as well as the stability of dielectric losses with temperature for high G content. These results correlate well with the increase in mechanical stiffness with an increase in G content for both SEBS/G and SEBS-MA/G composites. The activation energies for the dielectric relaxation processes detected in SEBS/G and SEBS-MA/G composites were also determined and discussed in connection with the mechanical, thermal, and structural properties resulting from thermogravimetric analysis, differential scanning calorimetry, Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy analyses.  相似文献   
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IntroductionAlready in its first implementation, the introduction of the Covid‐19 immunity certificate has generated some debate among the public. This debate might be a hindrance to the effective realization of this policy. This study aimed to systematically review published research evaluating public feeling of the Covid‐19 immunity certificate policy measure and to find which factors might influence its acceptance.MethodsWe followed the scoping review methods manual by the Joanna Briggs Institute. We included studies with no time limits that presented novel data, and no exclusions have been made based on study design. We excluded articles that presented just expert opinions.ResultsWe found and reviewed 17 articles. The included studies were conducted in two main countries (the United Kingdom and Switzerland), with the rest from Israel, Italy, Spain, Germany, Australia, Taiwan and China. Both qualitative and quantitative studies were included, and nonrepresentative samples were mostly used to explore the public feeling about the Covid‐19 immunity certification. The included studies showed that public views on immunity certification are quite contradictory and influenced by age, gender, ethnicity, political orientation and attitudes towards Covid‐19 vaccination. The topic more often addressed by the included studies was the public''s views on the positive and negative implications of the Covid‐19 immunity certificate in terms of ethical, legal and behavioural consequences of this measure.ConclusionThe varying acceptance rates are notable and may partly be linked to differences in demographics, Covid‐19 concerns and ideological beliefs, as seen in other health‐related tracking policies. Moreover, dominant factors behind the (un)success of this policy are complex and entangled with the cultural and political dimensions rather than being just technical. For this reason, it is important to expand psychosocial research to better understand the concerns behind health certifications and allow planning of culturally based and ethically sound suitable strategies. This would be very relevant to increasing public approval and compliance with this public health measure.Patient or Public ContributionThis does not apply to our work as it was a review paper.  相似文献   
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Multiple myeloma (MM) is an incurable hematologic neoplasm, whose poor prognosis is deeply affected by the propensity of tumor cells to localize in the bone marrow (BM) and induce the protumorigenic activity of normal BM cells, leading to events associated with tumor progression, including tumor angiogenesis, osteoclastogenesis, and the spread of osteolytic bone lesions. The interplay between MM cells and the BM niche does not only rely on direct cell-cell interaction, but a crucial role is also played by MM-derived extracellular vesicles (MM-EV). Here, we demonstrated that the oncogenic NOTCH receptors are part of MM-EV cargo and play a key role in EV protumorigenic ability. We used in vitro and in vivo models to investigate the role of EV-derived NOTCH2 in stimulating the protumorigenic behavior of endothelial cells and osteoclast progenitors. Importantly, MM-EV can transfer NOTCH2 between distant cells and increase NOTCH signaling in target cells. MM-EV stimulation increases endothelial cell angiogenic ability and osteoclast differentiation in a NOTCH2-dependent way. Indeed, interfering with NOTCH2 expression in MM cells may decrease the amount of NOTCH2 also in MM-EV and affect their angiogenic and osteoclastogenic potential. Finally, we demonstrated that the pharmacologic blockade of NOTCH activation by γ-secretase inhibitors may hamper the biological effect of EV derived by MM cell lines and by the BM of MM patients. These results provide the first evidence that targeting the NOTCH pathway may be a valid therapeutic strategy to hamper the protumorigenic role of EV in MM as well as other tumors.  相似文献   
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