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1.
Our aims were to separate and characterize secreted canine ocular mucins, and to provide definitive evidence of membrane-bound mucins at the canine ocular surface. Mucus was collected by suction from the ocular surface of normal dogs and dispersed in guanidine hydrochloride and a cocktail of protease inhibitors. Caesium chloride density gradient centrifugation separated secreted mucins from membranes, which were collected from the top of the gradients. Membranes were extracted with octyl glucoside and screened using lectins and anti-mucin antibodies. Gradient fractions containing secreted mucins were constituted into pools on the basis of differential lectin and antibody staining. High molecular weight material from each pool was purified by gel filtration. This material, and the membrane extract, were reduced and alkylated. Vacuum blotting of separated materials after agarose gel electrophoresis was used to compare subunit structure. Density gradient profiles indicated three principal secreted glycoprotein peaks: one staining strongly with anti-mucin antibodies. Gel filtration demonstrated that each contained high molecular weight material. Vacuum blots demonstrated the presence of two secreted glycoproteins with differently sized subunits. On the basis of buoyant density, one of these may be lipid complexed. Membrane extracted material stained with anti-mucin antibodies, and vacuum blotting of this material provided evidence for two membrane-bound components. In conclusion, we have shown that normal canine ocular mucus contains two secreted mucins, each exhibiting different subunit structure; one of these mucins may undergo lipid complexation. Normal canine ocular mucus also contains two membrane-bound mucins: one of which is unique among membrane mucins in showing subunit structure.  相似文献   
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An investigation into the effects of intermediate/variable final oxygen contents, in relation to the resultant microstructures and final magnetic properties of Pr–Fe–B- and Nd–Fe–B-type magnets in the as-sintered state has been undertaken. For low oxygen contents the Pr–Fe–B and Nd–Fe–B sintered magnets exhibited excessive grain growth on sintering. A high oxygen content resulted in the elimination of abnormal grain growth for both materials, on sintering, where the level of oxygen contamination appeared to affect the grain growth process, although not the grain growth mechanism. Differences, however, in grain growth behaviour for the Pr–Fe–B and Nd–Fe–B sintered magnets have been observed. A changing oxygen content resulted in a variable grain size and grain size distribution for both the Pr–Fe–B and Nd–Fe–B sintered magnets, resulting in a progressive change in intrinsic coercivity, with oxygen content.  相似文献   
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At a conference for female therapists in Canada, participants answered a questionnaire on issues and skills of therapists. Results indicate that the Ss were interested in (1) understanding themselves, their careers, and women's roles in society, and (2) a feminist approach to therapy. The responses suggest that the Ss' training as therapists was inadequate to the extent that it failed to address their own reality and that of women clients. (0 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Recent findings suggest that creep occurs during thermal cycling of ultrasonically bonded wires, the extent of which is influenced by the nature of the temperature cycle, particularly its peak temperature. In this work, this hypothesis is investigated through a study of the power-law creep behavior of bonded 375-μm aluminum wires that have been thermally cycled. Data from a study of two wire purity levels (99.999% and 99.99%) and two different cycling profiles (?55°C to 125°C and ?60°C to 170°C) are presented. Room-temperature creep stress exponents are derived for the wire bonds from constant-load nanoindentation tests and compared with their respective microstructures.  相似文献   
7.
Reviews the book, The Social Context of Premarital Sexual Permissiveness by Ira L. Reiss (1967). There seems little doubt that Reiss' sociological study has made an important contribution to the understanding of sexual attitudes in America today. The study does not investigate sexual behavior itself, although one stated purpose of the project was to examine the sociocultural correlates of premarital permissiveness. Reiss investigated attitudes toward premarital permissiveness and, as he himself mentions at one point, the relation between attitudes and actual behavior on this, as on other topics, may be inconsistent. Reiss grouped his data under seven propositions to elucidate the relationship between attitudes toward sexual permissiveness and sociocultural correlates. These seven propositions are then integrated into a theory: Two main factors are thought to contribute to premarital permissiveness--the influence of the family, and the influence of peers during the courtship period. While this theory falls short of adequately explaining premarital permissive behavior, it does suggest a framework for the future testing of specific hypotheses. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
This paper concerns the reliability of ultrasonically bonded high purity thick aluminium wires at elevated temperature. To date, the evolution of the microstructure of wire bonds during thermomechanical exposure and its influence on reliability have not been fully characterised and understood, particularly as they pertain to thermal cycling regimes which exceed 125 °C. Shear testing, indentation hardness and fine-scale microstructural data are reported here which show that the rate of wear-out can be influenced not only by the thermal cycling range (ΔT), but more importantly by the maximum temperature and duration to which bonds are exposed. There is evidence that significant annealing occurs during thermal cycling regimes with high Tmax values, which results in the removal of some of the damage accumulated and a reduction in the rate of crack propagation. The rate of bond degradation is also found to be faster for 99.99% (4 N) than 99.999% (5 N) pure Al wires. Analysis of the two wire compositions after thermal cycling suggests that this difference could be attributable to a difference in their creep resistance. In conclusion, our findings suggest that high purity Al wire bonds may be suitable for operation at temperatures which exceed 125 °C.  相似文献   
9.
This study shows for the first time that different glycosyltransferase defects in the biosynthesis of O-linked oligosaccharides give rise to the same GalNAc alpha-O-Ser/Thr determinant on Tn erythrocytes and colorectal carcinoma cells. The O-linked oligosaccharides isolated from the glycophorins of Tn erythrocytes contained predominantly alpha-N-acetylgalactosamine-O-Ser/Thr (Tn antigen) and sialyl-Tn. A marked reduction in normal sialylated oligosaccharides was also observed. Monoclonal antibody BRIC 111 raised against Tn erythrocytes reacted with both Tn erythrocytes and colorectal carcinoma tissues. Weak staining was detected in the supranuclear area and at the surface membranes in normal colorectal cells, but was absent from goblet cell vesicles. An increase in supranuclear staining over controls was found in tumour tissue and in the majority of resection margin specimens. The highest levels of staining were present in transitional mucosa, adjacent to the tumours where goblet vesicles were also positive. Glycosylation defects in the same patients were further studied by determination of the activity of glycosyltransferases in mucosal tissue from control and cancer patients. The reduction in or loss of beta 1-3 N-acetylglucosaminyl transferase activity to GalNAc-peptide in asialo-ovine submaxillary gland glycoprotein was detected by direct assay and by isolation of the oligosaccharides from the incubation products. No differences in N-acetylglucosaminyl-, galactosyl- or sialyl-transfer to Gal beta 1-3GalNAc in antifreeze glycoprotein or in sialyl transferase to asialo-ovine submaxillary gland glycoprotein were detected. Our study shows that the GalNAc alpha-O-Ser/Thr determinant on Tn erythrocytes and in colorectal carcinoma results from different glycosyltransferase defects in separate biosynthetic pathways for haematopoietic and epithelial tissues.  相似文献   
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