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91.
92.
Attention is directed toward the evaluation of motor insulation by a series of ac power factor and dc voltage-leakage tests at progressively higher voltages. A careful testing procedure is outlined that points out the need for uniform test conditions. Use of power factor tip-up, polarization indices, and voltage-leakage slopes are discussed as indicators of insulation quality before the dielectric ground test. Contamination of ground wall insulations by the ingress of such foreign elements as water, lubricating oil, cleaning solvents, and dirt is thought to be a leading cause for the maldistribution of high potentials across ground wall thickness. A brief theoretical discussion of voltage distribution across ground wall thicknesses is included to explain this phenomenon that is pictured as the main reason for mysterious ground failures during ground testing of otherwise sound insulation. 相似文献
93.
Pagano MA Poletto G Di Maira G Cozza G Ruzzene M Sarno S Bain J Elliott M Moro S Zagotto G Meggio F Pinna LA 《Chembiochem : a European journal of chemical biology》2007,8(1):129-139
Abnormally high constitutive activity of protein kinase CK2, levels of which are elevated in a variety of tumours, is suspected to underlie its pathogenic potential. The most widely employed CK2 inhibitor is 4,5,6,7-tetrabromobenzotriazole (TBB), which exhibits a comparable efficacy toward another kinase, DYRK1 a. Here we describe the development of a new class of CK2 inhibitors, conceptually derived from TBB, which have lost their potency toward DYRK1 a. In particular, tetrabromocinnamic acid (TBCA) inhibits CK2 five times more efficiently than TBB (IC50 values 0.11 and 0.56 microM, respectively), without having any comparable effect on DYRK1 a (IC50 24.5 microM) or on a panel of 28 protein kinases. The usefulness of TBCA for cellular studies has been validated by showing that it reduces the viability of Jurkat cells more efficiently than TBB through enhancement of apoptosis. Collectively taken, the reported data support the view that suitably derivatized tetrabromobenzene molecules may provide powerful reagents for dissecting the cellular functions of CK2 and counteracting its pathogenic potentials. 相似文献
94.
95.
Samanta Salvi Daniele Calistri Giorgia Gurioli Elisa Carretta Luigi Serra Roberta Gunelli Wainer Zoli Valentina Casadio 《International journal of molecular sciences》2014,15(7):12458-12468
Patients with non-muscle invasive bladder cancer (NMIBC) generally have a high risk of relapsing locally after primary tumor resection. The search for new predictive markers of local recurrence thus represents an important goal for the management of this disease. We studied the copy number variations (CNVs) of 24 oncogenes (MDM4, MYCN, ALK, PDGFRA, KIT, KDR, DHFR, EGFR, MET, SMO, FGFR1, MYC, ABL1, RET, CCND1, CCND2, CDK4, MDM2, AURKB, ERBB2, TOP2A, AURKA, AR and BRAF) using multiplex ligation probe amplification technique to verify their role as predictive markers of recurrence. Formalin-fixed paraffin-embedded tissue samples from 43 patients who underwent transurethral resection of the bladder (TURB) were used; 23 patients had relapsed and 20 were disease-free after 5 years. Amplification frequencies were analyzed for all genes and MDM4 was the only gene that showed significantly higher amplification in non recurrent patients than in recurrent ones (0.65 vs. 0.3; Fisher’s test p = 0.023). Recurrence-free survival analysis confirmed the predictive role of MDM4 (log-rank test p = 0.041). Our preliminary results indicate a putative role for the MDM4 gene in predicting local recurrence of bladder cancer. Confirmation of this hypothesis is needed in a larger cohort of NMIBC patients. 相似文献
96.
Roberto Pisano Antonello A. Barresi Luigi C. Capozzi Giorgia Novajra Irene Oddone Chiara Vitale-Brovarone 《Drying Technology》2017,35(8):933-938
ABSTRACTThis paper proposes a systematic work process for the rapid determination of resistance to vapor flow given by the products being freeze-dried. This approach couples mathematical modeling and 3D nondestructive X-ray imaging to reconstruct the internal structure of lyophilized samples. Knowledge of the internal structure is fundamental to better understand the relationship between freezing and within-product heterogeneity as well as between freezing and the drying behavior of the product being lyophilized. The method was validated upon mannitol-based formulations using various freezing protocols. This stepwise approach was demonstrated to be helpful to lyophilization professionals for the control of within-product heterogeneity and for the optimization of the cycle. 相似文献
97.
Rusciano G De Luca AC Pesce G Sasso A Oliviero G Amato J Borbone N D'Errico S Piccialli V Piccialli G Mayol L 《Analytical chemistry》2011,83(17):6849-6855
In this work, we establish the use of surface-enhanced Raman scattering (SERS) as a label-free analytical technique for the direct detection of G-quadruplex formation. In particular, we demonstrate that SERS analysis allows the evaluation of the relative stability of G quadruplexes that differ for the number of G tetrads and investigate several structural features of quadruplexes, such as the orientation of glycosidic bonds, the identification of distortions in the sugar-phosphate backbone, and the degree of hydrogen-bond solvation. Herein, the fluctuation of the SERS spectra, due to the specific interaction of vibrational modes with the SERS-active substrate, is quantitatively analyzed before and after quadruplex formation. The results of this study suggest a perpendicular orientation of the quadruplexes (with or without the 3'-tetra end linker) with respect to the silver colloidal surface, which opens new perspectives for the use of SERS as a label-free analytical tool for the study of the binding mode between quadruplexes and their ligands. 相似文献
98.
A Manni R Wechter S Gilmour MF Verderame D Mauger LM Demers 《Canadian Metallurgical Quarterly》1997,70(2):175-182
Inactivation of one X chromosome (X inactivation) in female mammals results in dosage compensation of X-chromosomally encoded genes between sexes. In the embryo proper of most mammals X inactivation is thought to occur at random with respect to the parental origin of the X chromosome. We determined on the cellular level the expression of the X-chromosomally encoded protein dystrophin in skeletal and cardiac muscle of female mice heterozygous for a null mutation of the dystrophin gene (mdx/+). In all muscles investigated (cardiac, anterior venter of digastric muscle, biceps brachii and tibialis anterior muscle) we found a mosaic expression of dystrophin-expressing versus non-expressing cells and determined their proportion with respect to the parental origin of the X chromosome. In all groups of mdx/+ mice the level and pattern of dystrophin expression were found to be dependent on the parental origin of the mdx mutation. Additionally, the extent of dystrophin expression was clearly dependent on the mouse strains (C57BL/10 and BALB/c) used to produce heterozygous mdx/+ mice. Variable differences and patterns of dystrophin expression in skeletal versus cardiac muscle were found that were strictly dependent on the parental source of the mdx mutation and the strain used to breed mdx/+ mice. Moreover, dystrophin expression was found to be different between the right side and the left side of the body in individual muscles, and this difference was clearly dependent on the parental origin of the X chromosome. Our data provide evidence that in the mouse embryo proper there is a non-random distribution of cells showing inactivation of the paternal versus the maternal X chromosome in skeletal and cardiac muscle, indicating a non-random X-inactivation. Besides gametic imprinting, strain-, tissue and position-dependent factors also appear to bias X inactivation. 相似文献
99.
C De Giovanni P Nanni A Sacchi S Soddu I Manni G D'Orazi S Bulfone-Paus T Pohl L Landuzzi G Nicoletti F Frabetti I Rossi PL Lollini 《Canadian Metallurgical Quarterly》1998,78(12):1541-1546
We recently reported that rhabdomyosarcoma cell lines express and secrete interleukin 15 (IL-15), a tightly regulated cytokine with IL-2-like activity. To test whether the p53-impaired function that is frequently found in this tumour type could play a role in the IL-15 production, wild-type p53 gene was transduced in the human rhabdomyosarcoma cell line RD (which harbours a mutated p53 gene), and its effect on proliferation and expression of IL-15 was studied. Arrest of proliferation was induced by wild-type p53; increased proportions of G1-arrested cells and of apoptotic cells were observed. A marked down-modulation of IL-15 expression, at both the mRNA and protein level, was found in p53-transduced cells. Because a direct effect of IL-15 on normal muscle cells has been reported, the presence of IL-15 membrane receptors was studied by cytofluorometric analysis. Rhabdomyosarcoma cells showed IL-15 membrane receptors, which are down-modulated by wild-type p53 transfected gene. In conclusion, wild-type p53 transduction in human rhabdomyosarcoma cells induces the down-modulation of both IL-15 production and IL-15 receptor expression. 相似文献
100.
An unilateral maxillary sinusitis is frequently caused by dental pathology. An odontogenic cyst in the maxillary sinus usually lacks accompanying symptoms of infection. In three patients, a 35-year-old man and two women aged 16 and 28, an odontogenic cyst in the maxillary sinus was diagnosed. Consultation of a maxillofacial surgeon is needed because orthopantomographic imaging is diagnostically most helpful. In these patients combined treatment by an ENT surgeon and a maxillofacial surgeon is important. 相似文献