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81.
A new class of potent, orally active phenyl piperazine-based GH secretagogues have been discovered from attempts to mimic the arrangement of the phenyl substituent in the spiroindanyl piperidine and spiroindoline sulfonamide privileged structures of 4 and 1, respectively. The best of these compounds, 18 (EC50 = 2.8 nM) is nearly as potent as MK-0677 for releasing GH from rat pituitary cells.  相似文献   
82.
T cells infiltrating the iris/ciliary body of Lewis rats with anterior uveitis (AU) that had been induced by myelin basic protein (MBP) immunization were previously found to share surface markers common to the T cells that cause experimental autoimmune encephalomyelitis (EAE). To determine whether these AU-associated T cells are in fact the same as those that infiltrate the central nervous system to cause EAE, we examined TCR V gene expression in T cells infiltrating the anterior chamber in rats with AU. As with EAE, we found a biased expression of Vbeta8.2 and Valpha2 in the iris/ciliary body and, although one would expect an influx of nonspecific inflammatory T cells, these biases were still evident at the peak of AU. An analysis of the TCR Vbeta8.2 and Valpha2 sequences derived from the iris/ciliary body demonstrated the presence of the same complementarity determining region 3 motifs found in MBP-specific T cells that are pathogenic for EAE and found in T cells derived from the central nervous system of rats with EAE. Finally, T cells isolated from the iris/ciliary body of rats with AU were found to proliferate in a specific fashion to MBP Ags. Thus, it appears that MBP-specific T cells are pathogenic for AU as well as EAE in the Lewis rat. In addition, the long-term presence of this highly restricted MBP response in the iris/ciliary body indicates that distinct immunoregulatory mechanisms exist in the environment of the eye. This provides an interesting model with which to address questions pertaining to the nature of T cells infiltrating the eye and their regulation during EAE and other systemic diseases.  相似文献   
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Systemic enzymes (wobenzime and wobe-mugos) were approved, that had been prescribed as part of polychemotherapy to 24 patients with malignant lymphomas, who presented with large masses of lymphatic nodes poorly resorbable against the background of polychemotherapy and who were assigned for a high-total dose irradiation, which fact would undoubtedly entail sclerosing of adjacent intact tissues. The use of the enzymes made for the optimum realization of the polychemotherapy effect and permitted avoiding a good many of undesirable side events and complication thereof. The above systemic enzymes are well tolerated by patients; they induce no significant changes in the cellular composition or in blood biochemical indices.  相似文献   
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The nitrogen solubility in the SiO2-rich liquid in the metastable binary SiO2-Si3N4 system has been determined by analytical TEM to be 1%–4% of N/(O + N) at 1973–2223 K. Analysis of the near edge structure of the electron energy loss peak indicates that nitrogen is incorporated into the silicate network rather than being present as molecular N2. A regular solution model with a positive enthalpy of mixing for the liquid was used to match the data for the metastable solubility of N in the presence of crystalline Si3N4 and to adjust the computed phase diagram. The solubility of Si3N4 in fused SiO2 is far less than reported in liquid silicates also containing Al, Mg, and/or Y. Apparently, these cations act as modifiers that break anion bridges in the silicate network and, thereby, allow further incorporation of Si3N4 without prohibitive amounts of network cross-linking. Finally, indications emerged regarding the diffuse nature of the Si3N4-SiO2 interface that leads to amorphous regions of higher N content.  相似文献   
89.
Silphinene Sesquiterpenes as Model Insect Antifeedants   总被引:3,自引:0,他引:3  
Silphinene sesquiterpenes are established chrysomelid antifeedants. In this work, nine silphinene analogs, 11-acetoxy-5-angeloyloxysilphinen-3-one (1), 11-acetoxy-5-tigloyloxysilphinen-3-one (2), 11-acetoxy-5-iso- butyryloxysilphinen-3-one (3), 11-hydroxy-5-angeloyloxysilphinen-3-one (4), 11,5-dihydroxysilphinen-3-one (5), 11,5-diacetoxysilphinen-3-one (6), 5,11-diisobutyryloxysilphinen-3-one (7), silphinen-3,5,11-trione (8), and O-methyl-5-epicantabrenolic acid methyl ester (10), and a presilphiperfolane sesquiterpene (9) were tested against several divergent insect species, including the lepidopteran Spodoptera littoralis, the chrysomelid Leptinotarsa decemlineata, and five aphid species, and their antifeedant effects were compared with those of picrotoxinin, a GABA-antagonist, and thymol, an allosteric modulator for insect GABA receptors. All insects tested responded to at least one silphinene analog and/or GABA antagonist. Compound 3 and thymol were effective antifeedants against all species tested except S. littoralis, with varying potencies according to their feeding ecologies. The toxicity of these compounds was species-dependent and did not correlate with their antifeedant effect.  相似文献   
90.
The compatibility of dyes is particularly important in regard to the time, reproducibility and levelness of dyeing. For basic dyes on acrylic fibres and anionic dyes on nylon, a characteristic of the dye—the compatibility value K— is valuable in determining whether it can be used in the same bath as others. Dyes having the same K-value are compatible under most dyeing conditions. For disperse dyes, K-values do not exist. In selecting such dyes for use together, other properties of the dyes and the concentrations to be used in the particular combination must be considered.  相似文献   
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