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991.
New derivatives of calix[4]arenes, containing two isoindole fragments in distal positions of the macrocycle upper rim were synthesized. According to NMR and molecular modeling data, the obtained calixarenes exist in “flattened cone” conformation with inclination angles of benzene rings to the macrocycle plane equal to 133–140° and 92–100°. Fluorometric studies showed the presence of self-aggregation of isoindolenylcalixarenes in acetone solutions starting from micromolar concentrations.  相似文献   
992.
Searching new structured black phosphorus (BP) and exploring intriguing functions and applications have become a hot topic so far.Here,we introduce a novel Iso-...  相似文献   
993.
The hybridization between the outmost s orbitals of metal (Bi3+,Sn2+,Pb2+,Ag+) and O 2p orbitals has been widely employed to develop innovative semiconductors w...  相似文献   
994.
The expression of E-cadherin has been investigated by the immunohistochemical method. The expression of E-cadherin is considered as a biomarker of junctions of intercellular adhesion in tissues samples with cervical intraepithelial neoplasias. The quantitative avidin-biotin-peroxidase method was used to estimate the expression. Precancer lesions, i.e., cervical intraepithelial neoplasias, CIN 1, 2, 3, precede invasive cancer of the cervix uteri by several years, the prognosis of which is variable in terms of regression and progression into invasive cancer. The expression of E-cadherin has been analyzed in cervical tissues of patients with various grades of CIN and microinvasive cancer (81 samples), as well as patients without CIN (ten samples). The sharp, statistically significant decrease in the expression of E-cadherin in CIN3 has been recorded compared to CIN1, CIN2, and the normal epithelium. It is reasonable to use this marker to assess the grade of the lesion and develop an individual prognosis of CIN progression. The data present a new way to construct pharmaceuticals based on compounds that influence E-cadherin expression.  相似文献   
995.
The magnetic relaxation efficiency of gadolilnium(III) and holmium(III) ions in 1-N-butyl-3-methylimidazolium chloride was investigated by the 35Cl/37Cl NMR method over the temperature range of 298?C393 K.  相似文献   
996.
The ion-selective properties of 1,5-bis[2-(hydroxyethoxyphosphoryl)phenoxy]-3-oxapentane H2R2 have been described. The molecular and crystal structure of H2R2 has been determined by powder X-ray crystallography and IR spectroscopy. The molecule has the twofold symmetry axis, orthorhombic crystal system, space group Pbcn, a = 16.830(2) ?, b = 8.866(15) ?, c = 15.7190(2) ?, V = 2346.1(6) ?3, Z = 4. A new CuR2 · 2H2O complex has been synthesized and characterized.  相似文献   
997.
The hydrolysis constants K h of tervalent lanthanum and lanthanide ions at 25°C have been determined by pH titration against the background of 0.1 M KNO3. pK h values change monotonically from 8.53 for La(OH)2+ to 7.41 for Lu(OH)2+ and from 26.56 for La(OH)3 to 21.43 for Lu(OH)3.  相似文献   
998.
The temperature and enthalpy of the melting of caffeine, which are 235.5 ± 0.1°C and 19.6 ± 0.2 kJ/mol, respectively, are determined by DSC. The melting entropy and the cryoscopic constant of caffeine are calculated.  相似文献   
999.
It is established that the photolysis of anthraquinone in both aerated and deoxygenated polymeric alcohols is not accompanied by reduction with the formation of anthrahydroquinone; as a result, an adduct of hydroxyanthracene and polymeric alcohol is formed.  相似文献   
1000.
The solvation of Gd3+ is studied in N,N-dimethylformamide by 1H and 14N NMR in the temperature range of 298–373 K.  相似文献   
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