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61.
The general one-particle spin states are considered. It is shown that information contained in a spin-1/2 state can be recorded in an equivalent form with the help of three mixed completely decoherent qubit states. The density matrix of such a system has the form of the tensor product of three diagonal matrices. The linear operator defined in the space of one-particle spin states generates some transform of the tensor products of the diagonal matrices. We construct this transform in the explicit form.  相似文献   
62.
Nonylphenyl-ethyleneoxide polymers containing 5, 9 and 30 ethyleneoxide groups per molecule build into the hydrophobic fatty acid chains of the cell membrane phospholipid dipalmitoyl-phosphatidylcholine (DPPC) resulting in a decreased main transition temperature, a decreased enthalpy of the main transition and in enhanced potassium permeability of DPPC liposomes. The -, - and -cyclodextrins form inclusion complexes with the tenzides lowering their free concentration. The complex formation lessens or sometimes totally prevents the membrane damaging effect of tensides. The effectivity order of cyclodextrins is CD>CD>CD.Presented at the Fourth International Symposium on Inclusion Phenomena and the Third International Symposium on Cyclodextrins, Lancaster, U.K. 20–25 July 1986.  相似文献   
63.
alpha-CD was converted into hexakis[2,6-di-O-(methoxydimethyl)methyl]-alpha-CD by a proton-catalyzed reaction with 2-methoxypropene. Subsequent benzylation under Brimacombe conditions resulted in the fully protected compound, from which the acid-sensitive acetal groups were removed to obtain hexakis(3-O-benzyl)-alpha-cyclodextrin. The structure of all of the compounds synthesized was confirmed by 13C J-ECHO, COSY, HETCOR and HMBC NMR measurements.  相似文献   
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The - and -cyclodextrin complexation of menthone and isomenthone was found to modify the ratio of epimeric menthol products formed upon a NaBH4/MeOH reduction of these ketones.Presented at the Fourth International Symposium on Inclusion Phenomena and the Third International Symposium on Cyclodextrins, Lancaster, U.K., 20–25 July 1986.  相似文献   
66.
1‐Acetyl‐ and 1‐propionyl‐2‐pyrazolines 11‐27 have been synthesized by the reaction of (3‐coumarinyl)chalcones 1‐10 with hydrazine in hot acetic acid or propionic acid. While 5‐aryl‐3‐(3‐coumarinyl)‐1‐phenyl‐2‐pyrazolines 28‐35 have been prepared by the reaction of (3‐coumarinyl)chalcones 1,3,5‐10 with phenylhydrazine in hot pyridine. Structures of all new compounds have been elucidated by microanalyses, 1H and 13C nmr spectroscopies.  相似文献   
67.
The lamellar organization of melt‐crystallized β‐isotactic polypropylene was studied by atomic force microscopy (AFM) after permanganic etching. Hedritic objects grown at a high crystallization temperature (140–143 °C) were investigated. Essential features of the hedritic development were revealed by the characteristic projections exposed at the sample surface. A three‐dimensional view of the morphology was obtained by AFM. Hedritic growth proceeded mainly by branching around screw dislocations resulting in new lamellae that further developed. Successive lamellar layers often diverged. Deviation from the planar lamellar habit was observed, varying with the position within the hedrite. Twisting of the lamellae also was observed occasionally in the vicinity of the screw dislocations. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 672–681, 2000  相似文献   
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69.
Background: It is well known that more than 90% of cancer deaths are due to metastases. However, the entire tumorigenesis process is not fully understood, and it is evident that cells spreading from the primary tumor play a key role in initiating the metastatic process. Tumor proliferation and invasion also elevate the concentration of regular and irregular metabolites in the serum, which may alter the normal function of the entire human homeostasis and possibly causes cancer metabolism syndrome, also referred to as cachexia. Methods: We report on the modification of commercially available hemodialysis membranes to selectively capture circulating tumor cells from the blood stream by means of immobilized human anti-EpCAM antibodies on the inner surface of the fibers. All critical steps are described that required in situ addition of the immuno-affinity feature to hemodialyzer cartridges in order to capture EpCAM positive circulating tumor cells, which represents ~80% of cancer cell types. Results: The cell capture efficiency of the suggested technology was demonstrated by spiking HCT116 cancer cells both into buffer solution and whole blood and run through on the modified cartridge. Flow cytometry was used to quantitatively evaluate the cell clearance performance of the approach. Conclusions: The suggested modification has no significant effect on the porous structure of the hemodialysis membranes; it keeps its cytokine removal capability, addressing cachexia simultaneously with CTC removal.  相似文献   
70.
This article demonstrates a new, modular approach to surface functionalization that harnesses chain entanglement. A layer of functionalized polyisobutylene, (PIB)‐ω, where ω = ‐OH, ‐thymine (T), ‐hexaethylene glycol (HEG), poly(ethylene glycol) (‐PEG‐OH), methoxy‐functionalized poly(ethylene glycol) (‐PEG‐OCH3), and ‐tetraethylene glycol‐α‐lipoate (TEG‐αL) was adhered to PIB‐based thermoplastic elastomer (TPE) surfaces. X‐ray photoelectron spectroscopy (XPS) at angles ranging from 20° to 75° showed decreasing polar group concentration with increasing penetration depth, confirming segregation of polar groups toward the surface. Water contact angle (WCA) of the PIB‐based TPE dropped from 95° to 79°?83° upon coating, and soaking in water for 24 h further decreased the WCA. Dynamic WCA measurements showed 40–30° receding angles, showing that stimulus from an aqueous environment elicits enrichment of polar groups on the surface. Fibrinogen (Fg) adsorption on the various surfaces was quantified using surface plasmon resonance (SPR). Static and dynamic WCA did not vary significantly among TPE + PIB‐ω surfaces, but there were dramatic differences in Fg adsorption: 256 ng/cm2 was measured on the native TPE, which dropped to 40 and 22 ng/cm2 on PIB‐PEG‐OCH3 and PIB‐PEG‐OH‐coated surfaces. PIB‐TEG‐αL‐coated surfaces presented the lowest Fg adsorption with 14 ng/cm2. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55 , 1742–1749  相似文献   
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