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排序方式: 共有2161条查询结果,搜索用时 14 毫秒
51.
NN Petrovichev OV Chistiakova AV Smirnov TD Rudinskaia VS Poltoranina 《Canadian Metallurgical Quarterly》1995,57(4):25-30
Anti-macrophage monoclonal antibody (Mab) D-11 was tested in surgical material and biopsies of non-epithelial tumors and tumor-like lesions from 181 patients in order to assess possibility of using this Mab for diagnosis of histiocytic tumors, malignant fibrous histiocytoma in particular. The study was performed in parallel on cryostat sections and smears by immuno-peroxidase method. It is established that D-11 reacts positively with both histiocytic tumors and tumors of other genesis this being a limiting factor in differential diagnosis of histiocytic tumors. However, taking into consideration 100% of positive results with histiocytic tumors only, this antibody can be used for exclusion of tumors studied from the group of histiocytomas in cases of negative reaction. 相似文献
52.
53.
VI Tselu?ko NA Kravchenko IV Shut' VI Cherkashina 《Canadian Metallurgical Quarterly》1994,28(5):73-77
Restriction fragment length polymorphism of the apo-B gene at the Xbal restriction site was detected. The association between RFLP of the apo-B gene and the level of lipid metabolism indices was revealed. The levels of total cholesterol LDLP CH and atherogenicity coefficient were significantly higher in homozygotes with this restriction site (X2X2) than in homozygotes X1X1 and heterozygotes. 相似文献
54.
NN Belosel''ski? OB Ershova IuN Pribytkov AV Bessarab 《Canadian Metallurgical Quarterly》1997,69(5):55-58
To specify shape of the vertebra in relation to age and sex, the authors studied roentgenomorphometric evidence upon examination of the thoracic and lumbar spine in 600 patients over 50. Vertebral deformities were found in 45.1 and 44.5% of the examined males and females, respectively. Changes corresponding to vertebral body fracture were recorded in 12.3% of the males and 15.3% of the females. Age-related trends in the frequency of various defects have been analyzed. The frequency differed in males and females. 相似文献
55.
L. A. Dushina D. S. Kornienko A. G. Kravchenko D. N. Litvin V. V. Mis’ko A. N. Rukavishnikov A. V. Senik K. V. Starodubtsev V. M. Tarakanov A. E. Chaunin 《Instruments and Experimental Techniques》2014,57(2):189-194
A photochronographic technique for studying the spectral composition and duration of radiation that accompanies the appearance of a shock wave on the rear surface of a loaded target has been developed. The spectral resolution of this technique was evaluated. A method of the through calibration of the recording channel using radiation of a source with the known spectrum was proposed. The results of the performed calibration are used to restore the spectral distribution on the basis of the obtained spectrochronograms. 相似文献
56.
Colour constancy of prints with vat dyes on cotton fabrics was investigated by computing the CMCCON02 colour inconstancy index with the key element CAT02 for chromatic adaptation transform. The results show that the highest changes in colour appearance can be expected when the average daylight is replaced with fluorescent light. If D65 daylight is replaced with some other type of daylight, such as D50 or D55, only minor colour deviations occur which do not substantially change the colour appearance of the prints. The analysis of the influence of the lightness and chromaticity of prints shows that the chromaticity of the samples significantly affects their colour constancy. The change of appearance of the prints with lower chroma because of changed illumination conditions is less probable. The influence of a dye blend composition was also investigated. On average, multi‐coloured dye blends have proved to be more colour constant. 相似文献
57.
Dr. Wojciech Schönemann Dr. Jonathan Cramer Tobias Mühlethaler Dr. Brigitte Fiege Marleen Silbermann Dr. Said Rabbani Dr. Philipp Dätwyler Dr. Pascal Zihlmann Dr. Roman P. Jakob Dr. Christoph P. Sager Dr. Martin Smieško Dr. Oliver Schwardt Prof. Dr. Timm Maier Prof. Dr. Beat Ernst 《ChemMedChem》2019,14(7):749-757
Antimicrobial resistance has become a serious concern for the treatment of urinary tract infections. In this context, an anti-adhesive approach targeting FimH, a bacterial lectin enabling the attachment of E. coli to host cells, has attracted considerable interest. FimH can adopt a low/medium-affinity state in the absence and a high-affinity state in the presence of shear forces. Until recently, mostly the high-affinity state has been investigated, despite the fact that a therapeutic antagonist should bind predominantly to the low-affinity state. In this communication, we demonstrate that fluorination of biphenyl α-d -mannosides leads to compounds with perfect π–π stacking interactions with the tyrosine gate of FimH, yielding low nanomolar to sub-nanomolar KD values for the low- and high-affinity states, respectively. The face-to-face alignment of the perfluorinated biphenyl group of FimH ligands and Tyr48 was confirmed by crystal structures as well as 1H,15N-HSQC NMR analysis. Finally, fluorination improves pharmacokinetic parameters predictive for oral availability. 相似文献
58.
Vujisić LV Makarov SE Curčić BP Ilić BS Tešević VV Gođevac DM Vučković IM Curčić SB Mitić BM 《Journal of chemical ecology》2011,37(12):1358-1364
Three European julid species, Cylindroiulus boleti, Leptoiulus trilineatus, and Megaphyllum bosniense, secrete mixtures of up to 12 different quinones. The major components in these species are 2-methoxy-3-methyl-1,4-benzoquinone
and 2-methyl-1,4-benzoquinone. 2-Methoxy-5-methylhydroquinone is detected for the first time in the Class Diplopoda. 2-Hydroxy-3-methyl-1,4-benzoquinone,
2,3-dimethoxyhydroquinone, 2-methyl-3,4-methylendioxyphenol, and 2,3-dimethoxy-5-methylhydroquinone are registered for the
first time in representatives of the family Julidae. The similar chemical composition of defense secretions in all analyzed
European julids and Pacific spirobolids supports the idea of the chemical consistency of defensive compounds in juliform millipedes. 相似文献
59.
It was demonstrated by a gas-volumetric method that humic acids from brown coal exhibit pronounced antioxidant properties, being the effective inhibitors of the model reactions of initiated radicalchain oxidation of hydrocarbons (cumene and ethylbenzene). This makes it possible to recommend humic acids for use as effective antioxidants for technical purposes and as promising biologically active natural antioxidants for the development of new classes of pharmaceuticals for medicine. 相似文献
60.
Viktor Dan’ko Katerina Michailovska Ivan Indutnyi Petro Shepeliavyi 《Nanoscale research letters》2014,9(1):165
We investigated plasmon-assisted enhancement of emission from silicon nanoparticles (ncs-Si) embedded into porous SiO
x
matrix in the 500- to 820-nm wavelength range. In the presence in the near-surface region of gold nanoisland film, ncs-Si exhibited up to twofold luminescence enhancement at emission frequencies that correspond to the plasmon resonance frequency of Au nanoparticles. Enhancement of the photoluminescence (PL) intensity was attributed to coupling with the localized surface plasmons (LSPs) excited in Au nanoparticles and to increase in the radiative decay rate of ncs-Si. It has been shown that spontaneous emission decay rate of ncs-Si modified by thin Au film over the wide emission spectral range was accelerated. The emission decay rate distribution was determined by fitting the experimental decay curves to the stretched exponential model. The observed increase of the PL decay rate distribution width for the Au-coated nc-Si-SiO
x
sample in comparison with the uncoated one was explained by fluctuations in the surface-plasmon excitation rate.