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排序方式: 共有320条查询结果,搜索用时 31 毫秒
61.
Lucio Díaz-Flores Ricardo Gutirrez Miriam Gonzlez-Gmez Maria Pino García Lucio Díaz-Flores Jr. Jos Luís Carrasco Pablo Martín-Vasallo 《International journal of molecular sciences》2021,22(7)
Several origins have been proposed for cancer-associated fibroblasts (CAFs), including resident CD34+ stromal cells/telocytes (CD34+SCs/TCs). The characteristics and arrangement of mammary CD34+SCs/TCs are well known and invasive lobular carcinoma of the breast (ILC) is one of the few malignant epithelial tumours with stromal cells that can express CD34 or αSMA, which could facilitate tracking these cells. Our objective is to assess whether tissue-resident CD34+SCs/TCs participate in the origin of CAFs in ILCs. For this purpose, using conventional and immunohistochemical procedures, we studied stromal cells in ILCs (n:42) and in normal breasts (n:6, also using electron microscopy). The results showed (a) the presence of anti-CD34+ or anti-αSMA+ stromal cells in varying proportion (from very rare in one of the markers to balanced) around nests/strands of neoplastic cells, (b) a similar arrangement and location of stromal cells in ILC to CD34+SCs/TCs in the normal breast, (c) both types of stromal cells coinciding around the same nest of neoplastic cells and (d) the coexpression of CD34 and αSMA in stromal cells in ILC. In conclusion, our findings support the hypothesis that resident CD34+SCs/TCs participate as an important source of CAFs in ILC. Further studies are required in this regard in other tumours. 相似文献
62.
Ahmed Abdelaal Ahmed Mahmoud M. Alkhatip Michail Georgakis Lucio R. Montero Valenzuela Mohamed Hamza Ehab Farag Jaqui Hodgkinson Hisham Hosny Ahmed M. Kamal Mohamed Wagih Amr Naguib Hany Yassin Haytham Algameel Mohamed Elayashy Mohamed Abdelhaq Mohamed I. Younis Hassan Mohamed Mohammed Abdulshafi Mohamed A. Elramely 《International journal of molecular sciences》2021,22(6)
SARS-CoV-2 currently lacks effective first-line drug treatment. We present promising data from in silico docking studies of new Methisazone compounds (modified with calcium, Ca; iron, Fe; magnesium, Mg; manganese, Mn; or zinc, Zn) designed to bind more strongly to key proteins involved in replication of SARS-CoV-2. In this in silico molecular docking study, we investigated the inhibiting role of Methisazone and the modified drugs against SARS-CoV-2 proteins: ribonucleic acid (RNA)-dependent RNA polymerase (RdRp), spike protein, papain-like protease (PlPr), and main protease (MPro). We found that the highest binding interactions were found with the spike protein (6VYB), with the highest overall binding being observed with Mn-bound Methisazone at −8.3 kcal/mol, followed by Zn and Ca at −8.0 kcal/mol, and Fe and Mg at −7.9 kcal/mol. We also found that the metal-modified Methisazone had higher affinity for PlPr and MPro. In addition, we identified multiple binding pockets that could be singly or multiply occupied on all proteins tested. The best binding energy was with Mn–Methisazone versus spike protein, and the largest cumulative increases in binding energies were found with PlPr. We suggest that further studies are warranted to identify whether these compounds may be effective for treatment and/or prophylaxis. 相似文献
63.
A nonlinear design procedure for microwave power amplifiers is presented. The methodology makes use of a complete nonlinear model for the active device and an exact nonlinear analysis method. Suitable harmonic loading conditions for efficient power performance are imposed simultaneously and consistently with the analysis. The procedure is much faster than conventional repeated nonlinear analyses. © 1995 John Wiley & Sons, Inc. 相似文献
64.
Many researchers install Campbell-Stokes sunshine recorders to evaluate the global irradiation from heliophany measurements using the well-known Ångström linear regression. Because of the statistical nature of this relation, the actual solar irradiation values are determined with some given standard deviation, the fluctuation of which a poor empirical solar radiation database can contribute to. In this paper a procedure (“cross-validation”) has been devised, based on 8 years of daily sunshine and daily global solar radiation data, in order to investigate the dependence of the general standard deviation on the size of the database. Therefore one can infer that a database of at least 14 years is necessary and may be sufficient not only to obtain, by Ångström regression, a trustworthy and statistically stable estimation of the daily global solar irradiation but, further, to set up a “theoretical” and statistically stable distribution of any climatic quantity. Beyond this limit, the variability of the climatological quantities originates from only their intrinsic statistical nature, independently of the size of the database used 相似文献
65.
66.
Luigi Calabrese Lucio Bonaccorsi Paolo Bruzzaniti Giuseppe Gullì Angelo Freni Edoardo Proverbio 《应用聚合物科学杂志》2018,135(15)
In this article, mechanical behavior under compression loads of an innovative adsorbent material, based on silicone composite foams filled with SAPO 34 zeolite, is presented. The innovative composite foams were obtained profiting by the dehydrogenative coupling of siloxane constituents. These new adsorbent systems have been proposed to overcome to the low mechanical stability of conventional SAPO‐34 coating for adsorption chiller. In this concern, static and cyclic compressive tests at room temperature have been carried out. Samples at increasing content of SAPO 34 zeolite were tested to evaluate the influence of the filler content on the mechanical behavior of the composite foam. The results showed that the presence of zeolite reduces the elastic limit of the foam and increases the strength. The foams evidenced also acceptable mechanical stability to cyclic compressive loads. The encouraging results confirm the possible use of these new composite foams as adsorbent materials for cyclic adsorption heat pumps. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46145. 相似文献
67.
Dorleta Jimenez de Aberasturi Malou Henriksen‐Lacey Lucio Litti Judith Langer Luis M. Liz‐Marzn 《Advanced functional materials》2020,30(14)
Methods to image complex 3D cell cultures are limited by issues such as fluorophore photobleaching and decomposition, poor excitation light penetration, and lack of complementary techniques to verify the 3D structure. Although it remains insufficiently demonstrated, surface‐enhanced Raman scattering (SERS) imaging is a promising tool for the characterization of biological complex systems. To this aim, a controllable 3D cell culture model which spans nearly 1 cm2 in surface footprint is designed. This structure is composed of fibroblasts containing SERS‐encoded nanoparticles (i.e., SERS tags), arranged in an alternating layered structure. This “sandwich” type structure allows monitoring of the SERS signals in the z‐axis and with mm dimensions in the xy‐axis. Taking advantage of correlative microscopy techniques such as electron microscopy, it is possible to corroborate nanoparticle positioning and distances in z‐depths of up to 150 µm. This study reveals a proof‐of‐concept method for detailed 3D SERS imaging of a complex, dense 3D cell culture model. 相似文献
68.
Multimedia Tools and Applications - In this work, we present Post-it Notes, a system for supporting vocabulary acquisition in a foreign language for primary school children. The system consists of... 相似文献
69.
Ecotoxicity of naproxen and its phototransformation products 总被引:4,自引:0,他引:4
Isidori M Lavorgna M Nardelli A Parrella A Previtera L Rubino M 《The Science of the total environment》2005,348(1-3):93-101
The occurrence of pharmaceuticals in the environment is of great concern and only few data are available about the adverse effects of such molecules and their derivatives on non-target aquatic organisms. This study was designed to assess the toxic potential of Naproxen, a nonsteroidal anti-inflammatory, Naproxen Na, its freely water soluble sodium salt and their photoproducts in the aquatic environment. Bioassays were performed on algae, rotifers and microcrustaceans to assess acute and chronic toxicity. Furthermore, possible genotoxic effects of photoderivatives were investigated using SOS chromotest and Ames fluctuation test. The results showed that photoproducts were more toxic than the parent compounds both for acute and chronic values, while genotoxic and mutagenic effects were not found. These findings suggested the opportunity to consider derivatives in ecotoxicology assessment of drugs. 相似文献
70.
Lucio Soibelman 《Construction Management & Economics》2013,31(2):202-203