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排序方式: 共有534条查询结果,搜索用时 31 毫秒
41.
Alisa Schnellbaecher Anton Lindig Maxime Le Mignon Tim Hofmann Brit Pardon Stephanie Bellmaine Aline Zimmer 《International journal of molecular sciences》2021,22(12)
Biomanufacturing processes may be optimized by storing cell culture media at room temperature, but this is currently limited by their instability and change in color upon long-term storage. This study demonstrates that one of the critical contributing factors toward media browning is tryptophan. LC-MS technology was utilized to identify tryptophan degradation products, which are likely formed primarily from oxidation reactions. Several of the identified compounds were shown to contribute significantly to color in solutions but also to exhibit toxicity against CHO cells. A cell-culture-compatible antioxidant, a-ketoglutaric acid, was found to be an efficient cell culture media additive for stabilizing components against degradation, inhibiting the browning of media formulations, and decreasing ammonia production, thus providing a viable method for developing room-temperature stable cell culture media. 相似文献
42.
D. Pasquet J. L. Gautier P. Pouvil 《Journal of Infrared, Millimeter and Terahertz Waves》1986,7(3):357-364
Very simple analytical expressions are proposed for the reflection coefficients of coupling holes used in FIR waveguide lasers. The relations are carried out for dielectric and metallic circular waveguides. 相似文献
43.
Synthetic and Biological Studies of Sesquiterpene Polygodial: Activity of 9‐Epipolygodial against Drug‐Resistant Cancer Cells
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Dr. Ramesh Dasari Annelise De Carvalho Derek C. Medellin Kelsey N. Middleton Dr. Frédéric Hague Marie N. M. Volmar Prof. Liliya V. Frolova Dr. Mateus F. Rossato Jorge J. De La Chapa Nicholas F. Dybdal‐Hargreaves Akshita Pillai Prof. Véronique Mathieu Prof. Snezna Rogelj Prof. Cara B. Gonzales Prof. João B. Calixto Prof. Antonio Evidente Dr. Mathieu Gautier Dr. Gnanasekar Munirathinam Prof. Rainer Glass Prof. Patricia Burth Dr. Stephen C. Pelly Prof. Willem A. L. van Otterlo Prof. Robert Kiss Prof. Alexander Kornienko 《ChemMedChem》2015,10(12):2014-2026
Polygodial, a terpenoid dialdehyde isolated from Polygonum hydropiper L., is a known agonist of the transient receptor potential vanilloid 1 (TRPV1). In this investigation a series of polygodial analogues were prepared and investigated for TRPV1‐agonist and anticancer activities. These experiments led to the identification of 9‐epipolygodial, which has antiproliferative potency significantly exceeding that of polygodial. 9‐Epipolygodial was found to maintain potency against apoptosis‐resistant cancer cells as well as those displaying the multidrug‐resistant (MDR) phenotype. In addition, the chemical feasibility for the previously proposed mechanism of action of polygodial, involving the formation of a Paal–Knorr pyrrole with a lysine residue on the target protein, was demonstrated by the synthesis of a stable polygodial pyrrole derivative. These studies reveal rich chemical and biological properties associated with polygodial and its direct derivatives. These compounds should inspire further work in this area aimed at the development of new pharmacological agents, or the exploration of novel mechanisms of covalent modification of biological molecules with natural products. 相似文献
44.
Zhirong Liao Dragos Axinte Maxime Mieszala Rachid M’Saoubi Johann Michler Mark Hardy 《CIRP Annals》2018,67(1):109-112
Whilst gamma prime (γ′) phase is the strengthening phase in Ni-based superalloys its influence on machining has been seldom investigated. This paper reports for the first time on the effect of γ′ upon machining of Ni-based superalloys when cutting with parameters yielding different cutting temperature intervals which lead to strengthening/softening effects on the workpiece (sub)surface. In-depth XRD, SEM/FIB, EBSD analysis and unique micro-pillar testing in the workpiece superficial layers indicated that with the increase of γ′ fraction the grain plastic deformation significantly decreased, while specific cutting energy can switch from low to high values influenced by the real cutting temperature. 相似文献
45.
Jorge Gutierrez Denis Pache Myriam Ariaudo Jean-Luc Gautier 《Analog Integrated Circuits and Signal Processing》2010,62(3):313-318
This paper presents a high speed, 9-bit RF Digital-to-Analog Converter based on a new architecture implemented in a 0.13 μm
BiCMOS process and able to adjust the output power by 45 dB to meet gain control requirements of the new communications standards
with a SFDR >25 dBc. The maximum test-demonstrated frequency is 1.4 GHz and the chip dissipates <25 mW. 相似文献
46.
L. A. P. Hoogenboom J. Tulliez J. -P. Gautier R. D. Coker J. -P. Melcion M. J. Nagler Th. H. G. Polman J. Delort-Laval 《Food Additives & Contaminants》2001,18(1):47-58
Peanut meal naturally contaminated with 3.5mg/kg aflatoxin B1 (AFB1) was spiked with radiolabelled AFB1 (meal14C-I0) and decontaminated by a smallscale copy of an industrial ammoniation process (meal 14C-I1). During the process 15% of the radioactivity was lost, whereas 90% of the remaining radiolabel could not be extracted from the meal. In the extractable part, AFB1 accounted for 10% of the radiolabel, consistent with a total AFB1 reduction of more than 99%. No degradation products were observed in the extracts. Four lactating cows were fed with a diet containing 15% of either meal 14C-I0 or 14C-I1 for 10 days. On day 9 of this treatment, respectively 23 and 67% of the radiolabel was excreted in the urine and faeces of cows fed meal 14C-I0, as compared with 2 and 101% in the case of cows fed meal 14C-I1. Milk contained respectively 1.35 (meal 14C-I0) and 0.25% (meal 14C-I1) of the radiolabel. Milk samples taken during the equilibrium stage contained respectively 5 and 0.5 ng/ml of AFB1-derived compounds. Aflatoxin M1 (AFM1) accounted for 50-80% of these compounds in the case of milk from cows fed 14C-I0, as compared with 6-20% in the case of 14C-I1. AFB1 to AFM1 carry-over rates for 14C-I0 or 14 相似文献
47.
48.
IR Kamalov VA Sandrikov SV Gautier OM Tsirulnikova OG Skipenko 《Canadian Metallurgical Quarterly》1998,7(2):101-108
BACKGROUND: The distinction between malignant mesothelioma (MM) and adenocarcinoma (ACA) in cytologic specimens frequently is difficult, often requiring immunocytochemistry to support the diagnosis. Recent reports have proposed the utilization of antibodies to mesothelial cell clone HBME-1 and thrombomodulin (TM), because they are immunoreactive in MM and less commonly reactive in ACA. Immunoreactivity for the monoclonal antibody CA 19-9 has been observed in many ACAs and reportedly is absent in MM. METHODS: In this study, immunostaining was performed on formalin fixed, paraffin embedded cell blocks from effusions or fine-needle aspirations using the avidin-biotin-peroxidase method. Thirty-eight MMs and 49 ACAs were tested using antibodies to CA 19-9, HBME-1, and TM. RESULTS: Anti-CA 19-9 stained only 1 of the 37 cases of MM tested (3%), but stained 24 of the 49 cases of ACA (49%). Anti-HBME-1 stained 34 of 38 cases of MM (89%), and 28 of 43 cases of ACA tested (65%). Anti-TM stained 24 of 36 cases of MM (67%), and 21 of 40 cases of ACA tested (53%). CONCLUSIONS: CA 19-9 has utility as part of an immunocytochemical panel for distinguishing ACA from MM, because a positive staining reaction would make the diagnosis of MM unlikely. Although HBME-1 and TM can identify MM positively, each frequently is detected in ACA, thus limiting the utility of these antibodies in cytologic specimens. 相似文献
49.
H Gahéry-Ségard V Molinier-Frenkel C Le Boulaire P Saulnier P Opolon R Lengagne E Gautier A Le Cesne L Zitvogel A Venet C Schatz M Courtney T Le Chevalier T Tursz JG Guillet F Farace 《Canadian Metallurgical Quarterly》1997,100(9):2218-2226
Animal studies indicate that the use of replication-deficient adenovirus for human gene therapy is limited by host antivector immune responses that result in transient recombinant protein expression and blocking of gene transfer when rechallenged. Therefore, we have examined immune responses to an adenoviral vector and to the beta-galactosidase protein in four patients with lung cancer given a single intratumor injection of 10(9) plaque-forming units of recombinant adenovirus. The beta-galactosidase protein was expressed in day-8 tumor biopsies from all patients at variable levels. Recombinant virus DNA was detected by PCR in day-30 and day-60 tumor biopsies from all patients except patient 1. A high level of neutralizing antiadenovirus antibodies was detected in patient 1 before Ad-beta-gal injection whereas it was low (patient 3) or undetectable in the other two patients. All patients developed potent CD4 type 1 helper T cell (Th1) responses to adenoviral particles which increased gradually over time after injection. Antiadenovirus cytotoxic T lymphocyte responses were consistently boosted in the two patients examined (patients 3 and 4). Sustained production of anti-beta-galactosidase IgG was observed in all patients except patient 1. Consistent with anti-beta-gal antibody production, all patients except patient 1 developed intense, dose-dependent Th1 responses to soluble beta-galactosidase which increased over time. Strong beta-galactosidase-specific cytotoxic T lymphocyte responses were detected in patients 2, 3, and 4. Our results clearly show that despite the intensity of antiadenovirus responses, transgene protein expression was sufficient to induce strong and prolonged immunity in three patients. Recombinant adenovirus injected directly into the tumor is a highly efficient vector for immunizing patients against the transgene protein. 相似文献
50.