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71.
Fish larvae and fish eggs were sampled from the inshore waters of eastern Lake Michigan from 1978 through 1980, using a benthic sled and a plankton net towed within 0.5 m of the lake bottom. Differences between estimates of ichthyoplankton abundance based on the benthic sled and those based on the plankton net towed near bottom were examined along with interactions between gear, bottom depth, and time of day. Time of day was determined to be an important factor in comparing these two gear, but data were inconclusive as to the effect of depth on gear differences. Abundance of fish eggs calculated using sled tow data was significantly higher than that for the plankton net. For nighttime collections, density of alewife Alosa pseudoharengus larvae sampled in the plankton net significantly exceeded that for the sled, whereas density of spottail shiner Notropis hudsonius larvae based on sled data was significantly higher than that based on the plankton net for day sampling. Overall, the plankton net appeared to be adequate for sampling abundance of alewife larvae, while the sled was preferred for sampling fish eggs, spottail shiner larvae, and the following less common, but apparently demersal larvae: trout-perch Percopsis omiscomaycus, johnny darter Etheostoma nigrum, ninespine stickleback Pungitius pungitius, and slimy sculpin Cottus cognatus. 相似文献
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Richard Blouin Gilles Grondin Jude Beaudoin Yoshi Arita Nathalie Daigle Brian G. Talbot Denis Lebel Jean Morisset 《In vitro cellular & developmental biology. Animal》1997,33(9):717-726
Summary This study describes the establishment and characterization of an immortalized cell line derived from the pancreas of an adult
H-2Kb-tsA58 transgenic mouse. These cells, designated IMPAN for IMmortalized PANcreatic cells, displayed a cobblestone appearance
typical of confluent epithelial cells and a distinct polarity in the organization of their cytoplasmic organelles. Immunocytochemical
studies revealed that all IMPAN cells stained positively for a wide range of markers characteristic of pancreatic acinar cells,
namely the secretory products α-amylase, chymotrypsinogen, DNAse, the lectinlike secretory protein PAP (pancreatitis associated
protein), and the zymogen granule membrane proteins GP-2 and gp300. They also stained positively for carbonic anhydrase II
and cytokeratin 19, two proteins characteristic of pancreatic duct cells, as well as for rab3A, a small GTP-binding protein
specifically localized in pancreatic islet cells. No reactivity was ever obtained with insulin antibodies. Taken together,
these results show that the IMPAN cells exhibit a phenotype comparable to exocrine pancreatic acinar cells. However the expression
of some proteins more specific to duct and islet cells make them similar to in vivo or in vitro growing acinar cells. The cell line should be a valuable model to study the mechanisms of growth, differentiation, and transformation
of the exocrine pancreatic acinar cell. 相似文献
74.
J.-Y. Le Guennec S. Jude P. Besson E. Martel P. Champeroux 《Prostaglandins, leukotrienes, and essential fatty acids》2010,82(4-6):173-177
It has been known since the 1970s that an increased consumption of n-3 long chain polyunsaturated fatty acids such as eicosapentaenoic acid and docosahexaenoic acid has cardioprotective effects. Epidemiological studies have reported that this effect is due to the prevention of the arrhythmias responsible for sudden cardiac death. Mechanistically, different hypotheses have been put forward to give an explanation. Among them, there are a direct effect of the polyunsaturated fatty acids on ion channels and/or a modification of the regulation of ion channels by protein kinase C’s. 相似文献
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Cryoelectron Microscopic Examination of Human Immunodeficiency Virus Type 1 Virions with Mutations in the Cyclophilin A Binding Loop 总被引:1,自引:1,他引:0
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Lawrence B. Kong DongSung An Bradley Ackerson Jude Canon Osvaldo Rey Irvin S. Y. Chen Paul Krogstad Phoebe L. Stewart 《Journal of virology》1998,72(5):4403-4407
The human immunodeficiency virus type 1 capsid protein contains a conserved P217X4PX2PX5P231 motif. Mutation at Pro-222 decreases virion incorporation of cyclophilin A, while mutation at Pro-231 abolishes infectivity. Although viral RNA incorporation and protease cleavage of the Gag precursor were not affected by these mutations, cryoelectron microscopy revealed a loss of virion maturation in P231A particles. 相似文献
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Delouvrié B Al-Kadhimi K Arnould JC Barry ST Cross DA Didelot M Gavine PR Germain H Harris CS Hughes AM Jude DA Kendrew J Lambert-van der Brempt C Lohmann JJ Ménard M Mortlock AA Pass M Rooney C Vautier M Vincent JL Warin N 《Bioorganic & medicinal chemistry letters》2012,22(12):4117-4121
Potent antagonists of the integrin α(5)β(1), which are RGD mimetics built from tyrosine are described. This paper describes the optimization of in vitro potency obtained by variation of two parts of the molecule, the central aromatic core and the amide moiety. 相似文献