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1.
Nickel oxide was prepared by the decomposition of nickel hydroxide and then the nickel oxide was reduced to form the nickel catalyst. The properties of the nickel oxide and the reduced nickel were studied in relation to the enantio-differentiating ability (e.d.a.) of a tartaric acid-NaBr-modified reduced nickel catalyst. The modified nickel catalyst prepared from nickel oxide with less non-stoichiometric oxygen produced a high e.d.a. for the hydrogenation of methyl acetoacetate. The high crystallinity of the nickel oxide and the resultant nickel would be required to attain a high e.d.a.  相似文献   
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Casein phosphopeptide amorphous calcium phosphate nano-complexes (CPP-ACP) in chewing gum, lozenges and mouthrinses have been shown to re-mineralize enamel subsurface lesions in human in situ experiments. The aim of this double-blind, randomized clinical study was to investigate the capacity of CPP-ACP added to bovine milk to re-mineralize enamel subsurface lesions in situ. Ten subjects drank milk containing either 2.0 or 5.0 g CPP-ACP/l or a control milk whilst wearing removable appliances with enamel slabs containing subsurface demineralized lesions. Each 200 ml milk sample was consumed once a day for each weekday over three consecutive weeks. After each treatment and one weeks rest the subjects crossed over to the other treatments. At the completion of the treatments the enamel slabs were removed and remineralization determined using microradiography and microdensitometry. The results demonstrated that all three milk samples re-mineralized enamel subsurface lesions. However, the milk samples containing CPP-ACP produced significantly greater remineralization than the control milk. The re-mineralizing effect of CPP-ACP in milk was dose-dependent with 2.0 and 5.0 g CPP-ACP/l producing an increase in mineral content of 70 and 148%, respectively, relative to the control milk. The differences in remineralization following exposure to the three milk samples were all statistically significant (P<0.001). In conclusion, this study shows that the addition of 2.0-5.0 g CPP-ACP/l to milk substantially increases its ability to re-mineralize enamel subsurface lesions.  相似文献   
3.
Novel polymer electrolyte aimed for space-selective electrochromic imaging was prepared with poly(vinylbutyral) (PVB), poly(ethyleneglycole) (PEG2000) and tetrabutylammonium perchlorate (TBAP). A spreading of the electrochromic image is a shortcoming when the electrochromic image is space-selectively formed by electrochemical reaction. This is due to a cell formation between colored and uncolored parts through ionic conductor. In order to inhibit the spreading, it would be effective to apply a polymer electrolyte with very low ionic conductivity at room temperature to the imaging system. On this basis, the present electrolyte was designed to have large difference in ionic conductivity between high and low temperatures. Namely, this polymer electrolyte enables writing and erasing at high temperature due to high ionic conductivity, and the image is expected to be preserved without change at ambient temperature due to very low ionic conductivity. The thermal and conductive properties of the polymer electrolyte were analyzed. Further, space-selective electrochromic image was formed on the device with the present polymer electrolyte at 100 °C, and was revealed to be stable without change for more than a week when the device was kept at 20 °C.  相似文献   
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Four prognostics factors were investigated for colorectal cancer metastases. 1) There were statistically more venous invasions using Victoria blue elastic staining in patients with liver or lymph node metastasis than in those without metastasis. 2) The immunohistochemical expression rate of c-erbB-2 in liver metastasis cases was 27%, which was significantly higher than 3% in no metastasis cases. 3) Sialyl Lewis x (SLex) is related with cell adhesion. SLex positive rates in vessel invasion cancer cells were 71.4% with metastasis and 31.0% without metastasis. 4) Matrilysin is one of MMPs and it was significantly increased with Dukes stage by fluorescence intensity.  相似文献   
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It has been recently shown that NGF is not only involved in the survival and development of sympathetic and neural crest-derived sensory neurons, but also in some mechanisms of the immune system. For this reason, we studied the content of NGF in CSF samples from patients with diseases in which neuroimmunological mechanisms seem to be involved (multiple sclerosis, amyotrophic lateral sclerosis, Alzheimer disease, chronic relapsing polyradiculoneuritis, Guillain-Barré syndrome, and tumors of the nervous system), as well as from a number of normal control subjects. We setup an ELISA aimed at the beta subunit of NGF, obtaining good validation tests and a detection limit of 28 pg beta NGF per ml. None of the samples was found to contain detectable levels of NGF and, when a concentration method for sample enrichment was used, only one patient was NGF-positive. This suggests that NGF is probably not involved in the neuroimmunological mechanisms underlying some inflammatory and degenerative diseases of the nervous system.  相似文献   
8.
Parasitic infections recognized as neglected tropical diseases are a source of concern for several regions of the world. Aminoglycosides are potent antimicrobial agents that have been extensively studied by biochemical and structural studies in prokaryotes. However, the molecular mechanism of their potential antiprotozoal activity is less well understood. In the present study, we have examined the in vitro inhibitory activities of some aminoglycosides with a 6′‐hydroxy group on ring I and highlight that one of them, 6′‐hydroxysisomicin, exhibits promising activity against a broad range of protozoan parasites. Furthermore, we have conducted X‐ray analyses of 6′‐hydroxysisomicin bound to the target ribosomal RNA A‐sites in order to understand the mechanisms of both its antibacterial and antiprotozoal activities at the molecular level. The unsaturated ring I of 6′‐hydroxysisomicin can directly stack on G1491, which is highly conserved in bacterial and protozoal species, through π–π interaction and fits closer to the guanidine base than the typically saturated and hydroxylated ring I of other structurally related aminoglycosides. Consequently, the compound adopts a lower energy conformation within the bacterial and protozoal A‐sites and makes pseudo pairs to either A or G at position 1408. The A‐site‐selective binding mode strongly suggests that 6′‐hydroxysisomicin is a potential lead for the design of next‐generation aminoglycosides targeting a wide variety of infectious diseases.  相似文献   
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Nd: YVO4 powders and thin films were successfuly synthesized by the sol–gel method using metal alkoxides. A homogeneous and stable solution was prepared by the reaction of Y(OEt)3, VO(O i Pr)3, and Nd(OEt)3 in 2-methoxyethanol. The precursor was a mixture of vanadium and yttrium double alkoxide. Precursor films were prepared by dip coating and crystallization to single-phase YVO4 at 500°C. Nd:YVO4 films were crystallized with (200) preferred orientation on glass substrates, which showed the characteristic optical absorption of neodymium.  相似文献   
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