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781.
782.
Some reforms, such as the passing of a prohibitive law or a binding agreement to solve a social dilemma, involve coercion. In hypothetical cases, Ss sometimes said they would not support coerced reforms even though they acknowledged that the reforms would improve matters. Ss justified such resistance by noting that the reform would harm some group (despite helping many others), that a choice would be taken away that people ought to be able to make (i.e., that a right would be violated), or that the reform would produce an unfair distribution of costs or benefits. These results were found when Ss indicated whether each justification was true or false (and their responses were correlated with their voting), when they chose justifications from a list, or when they provided open-ended responses. Ss also exhibited a status quo effect: They were more likely to vote against a reform than to vote to repeal the same reform once it was passed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
783.
VirB9 and VirB7 are essential components of the putative VirB membrane channel required for transfer of the T-complex from Agrobacterium tumefaciens into plants. In this report, we present a biochemical analysis of their interaction and cellular localization. A comparison of relative electrophoretic mobilities under nonreducing and reducing conditions suggested that they form thiol-sensitive complexes with other proteins. Two-dimensional gel electrophoresis identified one complex as a heterodimer of VirB9 and VirB7 covalently linked by a disulfide bond, as well as VirB7 homodimers and monomers. Immunoprecipitation with VirB9-specific antiserum isolated the heterodimeric VirB9-VirB7 complex. Incubation with reducing agent split the complex into its constituent VirB9 and VirB7, which further confirmed linkage via cysteine residues. The interaction between VirB9 and VirB7 also was observed in the yeast two-hybrid system. Membrane attachment of VirB9-VirB7 may be conferred by lipoprotein modification, since labeling with [3H]palmitic acid in A. tumefaciens verified that VirB7 is a lipoprotein associated with VirB9. VirB9 and VirB7 showed equal distribution between inner and outer membranes, in accord with their proposed association with the transmembrane VirB complex. 相似文献
784.
BACKGROUND AND OBJECTIVE: To determine if either silicone oil or sulfur hexafluoride gas (SF6) is superior to the other in the treatment of complex retinal detachment after previously failed vitreous surgery. PATIENTS AND METHODS: In this randomized clinical trial, 18 patients received treatment with silicone oil and 16 patients received SF6. The primary outcome was defined as successful anatomic attachment of the retina. Secondary outcomes included the time to retinal detachment, visual acuity, anatomic macular attachment, and any complications of surgery. RESULTS: The odds of successful reattachment with silicone oil were 50% greater than they were with SF6, but this difference was not statistically significant. There were no differences between the two groups in any of the secondary outcomes. CONCLUSIONS: This study did not have enough statistical power to detect a small but clinically important difference between the two treatment groups. Physicians must use their clinical judgment to select a vitreal substitute for complex retinal detachment when clinical trials are inconclusive. Data pooling is one method of overcoming the limitation of clinical trials with small sample sizes. 相似文献
785.
CC Yen CH Tzeng JH Liu TJ Chiou RK Hsieh WS Wang PM Chen 《Canadian Metallurgical Quarterly》1997,60(4):213-218
The antigenic components of Fasciola gigantica somatic extract were revealed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting technique using sera from patients with F. gigantica infection, patients with clinically diagnosed fascioliasis, patients with other infections/illness and healthy adults. By SDS-PAGE, it was found that the somatic product comprised more than 22 polypeptides. Immunoblotting analysis revealed at least 13 components which were strongly recognized by sera of patients with fascioliasis. These antigenic components had molecular weights ranging from less than 14.4 to more than 94 kDa. One antigenic component, i.e. 38 kDa was found to give a consistent reaction with sera of patients with fascioliasis (100% sensitivity and 96.7% specificity). The finding suggests that the 38 kDa components may be a potential diagnostic antigen for fascioliasis. 相似文献
786.
Macrolide antibiotics are clinically important antibiotics which are effective inhibitors of protein biosynthesis in bacterial cells. We have recently shown that some of these compounds also inhibit 50S ribosomal subunit formation in Escherichia coli. Now we show that certain macrolides have the same effect in two gram-positive organisms, Bacillus subtilis and Staphylococcus aureus. Assembly in B. subtilis was prevented by erythromycin, clarithromycin, and azithromycin but not by oleandomycin. 50S subunit formation in S. aureus was prevented by each of seven structurally related 14-membered macrolides but not by lincomycin or two streptogramin antibiotics. Erythromycin treatment did not stimulate the breakdown of performed 50S subunits in either organism. The formation of the 30S ribosomal subunit was also unaffected by these compounds. Assembly was also inhibited in a B. subtilis strain carrying a plasmid with the ermC gene that confers macrolide resistance by rRNA methylation. These results suggest that ribosomes contain an additional site for the inhibitory functions of macrolide antibiotics. 相似文献
787.
EC Weir WM Philbrick M Amling LA Neff R Baron AE Broadus 《Canadian Metallurgical Quarterly》1996,93(19):10240-10245
Parathyroid hormone-related peptide (PTHrP) was initially identified as a product of malignant tumors that mediates paraneoplastic hypercalcemia. It is now known that the parathyroid hormone (PTH) and PTHrP genes are evolutionarily related and that the products of these two genes share a common receptor, the PTH/PTHrP receptor. PTHrP and the PTH/PTHrP receptor are widely expressed in both adult and fetal tissues, and recent gene-targeting and disruption experiments have implicated PTHrP as a developmental regulatory molecule. Apparent PTHrP functions include the regulation of endochondral bone development, of hair follicle formation, and of branching morphogenesis in the breast. Herein, we report that overexpression of PTHrP in chondrocytes using the mouse type II collagen promoter induces a novel form of chondrodysplasia characterized by short-limbed dwarfism and a delay in endochondral ossification. This features a delay in chondrocyte differentiation and in bone collar formation and is sufficiently marked that the mice are born with a cartilaginous endochondral skeleton. In addition to the delay, chondrocytes in the transgenic mice initially become hypertrophic at the periphery of the developing long bones rather than in the middle, leading to a seeming reversal in the pattern of chondrocyte differentiation and ossification. By 7 weeks, the delays in chondrocyte differentiation and ossification have largely corrected, leaving foreshortened and misshapen but histologically near-normal bones. These findings confirm a role for PTHrP as an inhibitor of the program of chondrocyte differentiation. PTHrP may function in this regard to maintain the stepwise differentiation of chondrocytes that initiates endochondral ossification in the midsection of endochondral bones early in development and that also permits linear growth at the growth plate later in development. 相似文献
788.
IP Singh AK Chopra DH Coppenhaver E Smith J Poast S Baron 《Canadian Metallurgical Quarterly》1995,27(4):375-388
Brain tissue extracts from vertebrates were examined for non-specific, broad-spectrum virus inhibitors, previously identified and characterized from other body tissues and fluids. An antiviral activity found in human, bovine, ovine, porcine, lapine, murine and piscine brain tissues shares some properties with a contact blocking-virus inhibitor, which was previously found only in cell culture supernatants. The inhibitor was active against (in order of sensitivity to inhibitor) Banzi, Sindbis, Bunyamwera, Newcastle disease, herpes simplex I, Semliki forest, polio I, mengo, vaccinia and vesicular stomatitis viruses. It is approximately 4000 kDa and possesses a complex structure containing protein, carbohydrate and lipid moieties. The inhibitor does not directly neutralize virus or induce an antiviral state in cells, but appears to act early in the replication cycle, most likely by preventing virus attachment to target cells. Its occurrence in concentrations sufficient to reduce virus yield in cell cultures at least 30-fold may indicate a role in limiting viral infections of the central nervous system. 相似文献
789.
K Klippenstein DM O'Day RD Robinson TE Williams WS Head 《Canadian Metallurgical Quarterly》1993,12(6):512-516
Dutch-belted rabbits with corneal epithelium either intact or debrided were injected subconjunctivally with 300 microliters of one of six antifungal agents: 10 mg/ml miconazole, 5 mg/ml fluconazole, 5 mg/ml ketoconazole, 2.5 mg/ml itraconazole, and 5 mg/ml amphotericin B. At intervals of 10 min to 96 h after injection, animals were killed and corneas removed at the limbus. Three vertical strips from the right cornea and four contiguous 3-mm disks trephined from the central vertical axis of the left cornea were placed on agar plates seeded with an appropriate indicator organism. After 24 h of incubation, the zones of inhibition were measured. For itraconazole, miconazole, fluconazole, saperconazole, and ketoconazole, central corneal levels peaked by 2 h in normal and debrided corneas. Little or no drug was detectable after 4-8 h, except for itraconazole, which persisted in the cornea for at least 24 h in both normal and debrided corneas. Peak levels of amphotericin B in the central cornea were achieved after 2 h in rabbits with debrided corneas, with no drug activity measured after 8 h. There were no detectable levels of drug found in the central corneas of rabbits with intact corneal epithelium. On the basis of this pilot study, the method offers a rapid approach to the screening of antifungal agents for possible use by subconjunctival injection. 相似文献
790.