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The Australasian and Ivory Coast deep-sea microtektites have fission track ages of 0.71 and 1.09 million years, respectively. These ages are in good agreement with the ages of deposition of the microtektites determined from paleomagnetic data. Both the fission track ages and ages of deposition of the microtektites agree with the potassium/ argon and fission track ages of tektites from the respective tektite strewn fields.  相似文献   
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Research has documented immobilization of rodents, rabbits, guinea pigs and dogs by mechanical means, typically using neck clips or inversion ('animal hypnosis'). In contrast, only a few studies of mechanical immobilization of cats are available, although some success has been reported in the literature. Domestic cats may be effectively immobilized by clips placed along the animal's dorsum. We use the term 'pinch-induced behavioral inhibition' (PIBI) for this behavior because it describes both the method and the response, while avoiding the more anthropomorphic term 'hypnosis'. We investigated the effectiveness of PIBI and its neurological and habituation effects in healthy cats and cats with idiopathic cystitis (IC). Although not all cats were susceptible to PIBI and effectiveness varied among individuals, PIBI was useful for gentle restraint in most cats.  相似文献   
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Pilus proteins from Escherichia coli serotypes O1, O2, and O78 pathogenic to poultry were compared with regard to their antigenic relatedness and partial amino acid sequences. Agglutination, immunodiffusion, and immunoblot assays with polyclonal antibodies to these pili showed that these pili not only share some common antigens but also contain antigens unique to each pilus. The partial amino-terminal amino acid sequences support our earlier findings that the pili are different but contain some structural homologies.  相似文献   
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Alterations of the phospholipid (PL) compositions of body fluids are assumed to be indicative of inflammatory diseases, e.g. rheumatoid arthritis (RA). Recently, we have shown that particularly the phosphatidylcholine/lysophosphatidylcholine (PC/LPC) ratio determined in human synovial fluids (SF) and sera represents a reliable measure of the inflammatory state in RA patients. However, it is not yet clear to what extent the PC/LPC ratio is also affected by nutrition habits. In the present study, the PL and the corresponding acyl chain compositions of human body fluids (SF and serum of RA patients as well as serum from healthy volunteers) are compared with those of two other mammalian species (horses and dogs suffering from degenerative joint diseases as well as healthy controls) by high-resolution 31P-nuclear magnetic resonance (NMR) spectroscopy and matrix-assisted laser desorption and ionization time-of-flight mass spectrometry (MALDI-TOF MS). The most important result of this study is that the PL compositions of SF and serum of horse and dog are comparable with those of human body fluids. Compared with humans, however, the horse body fluid contains less PCs with highly unsaturated arachidonoyl residues, while that of dogs possesses the highest content of arachidonoyl-containing PC. These species-related differences stem primarily from different nutrition habits (meat vs. plants).  相似文献   
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In the present study, we describe the expression of equine IL2 and IL4. The cDNA of equine IL2 or IL4 was cloned in a mammalian expression vector, containing c-terminal myc- and six histidines His(6)-epitopes for recognition and purification of equine cytokines. The vector constructs were used for transfection of chinese hamster ovary (CHO) cells. Purified equine cytokines were characterised by western blotting. Equine IL2 was secreted with a molecular weight of approximately 17.1kDa, whereas IL4 was expressed in three different sizes of 17.1, 19.6 and 22.1kDa, probably due to different glycosylation modifications. The biological activities of both cytokines were tested by proliferation assays using leukoagglutinin (LAG) prestimulated equine PBMC. Both, equine IL2 and IL4 induced dose-dependent lymphocyte proliferation. In contrast to IL4, IL2 supported the proliferation of B cells.  相似文献   
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Technical note: a double L intestinal cannula for cattle   总被引:1,自引:0,他引:1  
A double L-shaped intestinal cannula was developed in an attempt to overcome problems observed previously with simple T-type cannulas. The cannula was constructed from cyclopolyvinyl chloride water pipe fittings. Construction materials were fairly rigid, but by connecting the split cannula pieces with elastic castration bands the cannula had some flexibility. Placing a short cone over the exposed cannula barrel reduced mechanical damage to the intestine. The double L cannula required a much smaller incision in the intestine during surgical insertion than a T-type cannula; it also simplified replacement. Construction is described; use and performance of the cannula has been satisfactory.  相似文献   
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