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Journal of Ethology - The article Herding mechanisms to maintain the cohesion of a harem group.  相似文献   
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Punctin (ADAMTSL-1) is a secreted molecule resembling members of the ADAMTS family of proteases. Punctin lacks the pro-metalloprotease and the disintegrin-like domain typical of this family but contains other ADAMTS domains in precise order including four thrombospondin type I repeats. Punctin is the product of a distinct gene on human chromosome 9p21-22 and mouse chromosome 4 that is expressed in adult skeletal muscle. His-tagged punctin expressed in stably transfected High-Five(TM) insect cells was purified to apparent homogeneity by Ni-chromatography of conditioned medium. The NH(2) terminus is not blocked and has the sequence EEDRD and so forth as determined by Edman degradation, demonstrating signal peptidase processing. Recombinant epitope-tagged punctin has a calculated mass of 59,991 Da but exhibits major molecular species of 61970 +/- 6 Da and 62131 +/- 5 Da as measured by liquid chromatography electrospray mass spectrometry. Punctin is a glycoprotein based on carbohydrate staining and liquid chromatography electrospray mass spectrometry glycopeptide analysis. Glycosylation occurs at a single N-linked site as demonstrated by altered electrophoretic migration of punctin expressed in the presence of tunicamycin A. Punctin contains disulfide bonds based on antibody accessibility and electrophoretic migration under reducing versus nonreducing conditions. Rotary shadowing demonstrates that punctin is hatchet-shaped having a globular region attached to a short stem. In transfected COS-1 cells, punctin is deposited in the cell substratum in a punctate fashion and is excluded from focal contacts. Punctin is the first member of a novel family of ADAMTS-like proteins that may have important functions in the extracellular matrix.  相似文献   
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Summary Immunohistochemical distribution of NADPH-cytochrome P-450 reductase (NADPH-ferrihaemoprotein reductase; EC 1.6.2.4.) in the liver lobule was examined during development of the rat. From the 19th day of gestation to 4 days after birth, the enzyme was distributed uniformly throughout the lobule. The immunostaining for the enzyme was weak before birth, and became slightly stronger after birth. A slightly uneven distribution of immunoreactivity, stronger in perivenular zones, appeared at 5 days after birth. Then, the staining intensity in perivenular zones became progressively stronger with age, except for a slight increase between 10 and 20 days of age. The intensity in periportal zones also increased gradually, although it remained weaker than that in perivenular zones. Around 30 days of age, the distribution of the immunostaining, stronger in perivenular than in periportal zones, was similar to that seen in the lobules of adult animals. thus, heterogeneity among hepatocytes with respect to the enzyme content is not present in fetal and newborn rats but develops gradually during postnatal development; the postnatal growth of the liver is accompanied by a change in the pattern of the distribution of this enzyme within the lobule.  相似文献   
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The intracellular location of nitrate reductase in spinach leaveswas examined by applying an immunocytochemical method. Thinsections were first treated with immunopurified anti-nitratereductase monospecific antibodies, followed by incubation withcolloidal gold-labelled goat anti-rabbit immunoglobulin G asa marker. The nitrate reductase was specifically located inthe chloroplast. When anti-nitrate reductase antibodies wereomitted, or when pre-immune serum was used no label was observed. (Received October 30, 1986; Accepted December 25, 1986)  相似文献   
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MethodsMice with mutant SOD1 (G93A) transgene, a model for familial ALS, were used in this study. The expression of the major inflammatory cytokines, IL-6, IL-1β and TNF-α, in spinal cords of these SOD1 transgenic (TG) mice were assessed by real time PCR. Mice were then crossed with IL-6(-/-) mice to generate SOD1TG/IL-6(-/-) mice. SOD1 TG/IL-6(-/-) mice (n = 17) were compared with SOD1 TG/IL-6(+/-) mice (n = 18), SOD1 TG/IL-6(+/+) mice (n = 11), WT mice (n = 15), IL-6(+/-) mice (n = 5) and IL-6(-/-) mice (n = 8), with respect to neurological disease severity score, body weight and the survival. We also histologically compared the motor neuron loss in lumber spinal cords and the atrophy of hamstring muscles between these mouse groups.ResultsLevels of IL-6, IL-1β and TNF-α in spinal cords of SOD1 TG mice was increased compared to WT mice. However, SOD1 TG/IL-6(-/-) mice exhibited weight loss, deterioration in motor function and shortened lifespan (167.55 ± 11.52 days), similarly to SOD1 TG /IL-6(+/+) mice (164.31±12.16 days). Motor neuron numbers and IL-1β and TNF-α levels in spinal cords were not significantly different in SOD1 TG /IL-6(-/-) mice and SOD1 TG /IL-6 (+/+) mice.ConclusionThese results provide compelling preclinical evidence indicating that IL-6 does not directly contribute to motor neuron disease caused by SOD1 mutations.  相似文献   
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Two species of fiddler crab, Uca tetragonon(Herbst, 1790) and Uca vocans(Linnaeus, 1758), which belong to the subgenus Gelasimus, dwell on rocky shores and muddy–sandy tidal flats, respectively, in Phuket Is., Thailand. We investigated their feeding ecology in relation to the morphology of their feeding organs: minor food-handling chelipeds and maxillipeds. U. tetragononfed chiefly on rocks covered by filamentous green algae. U. vocansfed on the emerged sand and in shallow water along the shoreline and in pools. While feeding, both crabs made sand pellets beneath their mouthparts and discarded them, indicating that they divided the matter scooped up with their minor chelipeds into edible and inedible fractions by using the maxillipeds in the water passing through their buccal cavity. The morphology of maxillipeds hardly differed between the two species, which means that both species are flotation-feeders. The morphology of their minor chelipeds, however, differed: the tips of the dactyl and pollex were flat in U. tetragononand pointed in U. vocans.When the minor cheliped was closed, U. tetragononhad a hemispherical space in the distal one-fourth of the gape, which was closed by the framing keratin layers and a few setae of the dactyl and pollex. On the other hand, U. vocanshad an ellipsoidal space in the distal half of the gape. We consider these morphological characters to be adaptations to the different feeding substrates for retaining more food-laden sediment. We discuss the role of the setae on the minor chelipeds on the basis of the morphological differences between populations of U. tetragononin Phuket Is. and East Africa where the crab inhabits muddy–sandy tidal flats.  相似文献   
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