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61.
A. C. Smith 《Journal of fish biology》1980,16(1):1-4
Evidence is presented of lethal blood clot formation in fishes. A variety of factors commonly encountered under aquacultural conditions may generate such clots. 相似文献
62.
63.
Polyclonal antibodies prepared against each of the calcimedins were utilized to determine their tissue distribution. The immunological survey of rat tissues revealed that the levels of the 35-kDa calcimedin varied, while the amount of the 67-kDa calcimedin was relatively constant in the tissues examined. A new immunoreactive species, 52 kDa, was detected with the antibody to the 35-kDa calcimedin; this protein appears to be the predominant immunoreactive species in the tissues examined. Antibodies to the 35-kDa calcimedin were also used to compare many other calcium-binding proteins in order to determine immunological relationships. These comparisons demonstrate that the epidermal growth factor receptor/kinase substrate (p35), the src kinase substrate (pp36), and calregulin are immunologically unrelated to the calcimedins. However, it was found that the 67-kDa calcimedin and the p70 calelectrin are identical, as are the 35-kDa calcimedin and the p32.5 calelectrin. The calimedins are a subset of the chromobindins. In addition, the antibody to the 35-kDa calcimedin also cross-reacts with synexin, which may be related to the new 52-kDa immunoreactive protein identified. 相似文献
64.
A recombinant plasmid carrying the proBA (pro-74) mutant allele which governs osmotic tolerance and proline overproduction was constructed by using the broad-host-range plasmid vector pQSR49. The physiological, biochemical, and genetic properties of strains carrying the pQSR49 derivatives pMJ101 and pMJ1, mutant and wild type, respectively, were investigated. pMJ101 conferred enhanced osmotolerance compared with strains carrying the wild type, pMJ1. These results are in contrast to those obtained previously with strains carrying recombinant plasmids based on pBR322 that failed to confer the osmotic tolerance phenotype. gamma-Glutamyl kinase (first step in proline biosynthesis) from strains carrying pMJ101 was 200-fold less sensitive to feedback inhibition than was the wild-type enzyme. As expected, the intracellular proline levels of strains carrying pMJ101 were more than an order of magnitude higher than those of the wild type. An analysis of copy number revealed that the pQSR49 constructs were present in the cell at a level six- to eightfold lower than those of the pBR322 recombinants, which may account for the difference in phenotype. We found that the genetic stability of the pQSR49 derivative in a variety of gram-negative bacteria was dependent on the insert orientation and the presence of foreign DNA on the plasmid. These factors may be significant in future studies aimed at expanding the osmotolerance phenotype to a broad range of gram-negative bacteria. 相似文献
65.
L Takemoto J Smith T Kodama 《Biochemical and biophysical research communications》1987,142(3):761-766
Polyclonal antisera to three synthetic peptides of bovine MIP26K have been used in combination with Western blot analysis to probe for changes of the MIP26K molecule during human senile cataractogenesis. Anti-MIP26K229-237 binds well to the 26K component from cataractous lens membranes, but binds poorly to the same component from normal lens. In contrast, antisera to two other sequences of MIP26K (anti-MIP26K252-259 and anti-MIP26K256-263) bind approximately equally well to the 26K component from either cataractous or normal lens. Together, these results demonstrate that during cataract development there is a selective covalent change in a region of the MIP26K molecule that may have profound effects upon the ability of this molecule to facilitate intercellular communication between lens fiber cells. 相似文献
66.
Lymphatic drainage in patients after replantation of extremities 总被引:1,自引:0,他引:1
Lymph drainage was studied by means of lymph scintigraphy in eight patients in whom successful replantation of a totally or subtotally amputated extremity had been performed. Scintigrams were made after subcutaneous injection of technetium-99m in the replanted part of the patient and the contralateral, normal extremity. In all scintigrams, axillary or inguinal lymph node activity is seen, implying drainage of lymph by means of the lymph vessels. Retention of colloid in the replanted part (79 to 94 percent) shows no significant difference with the contralateral, normal side (86 to 94 percent). Unquestionable evidence of regeneration of lymphatics in humans is delivered in the three patients, in whom lymph node activity and normal retention percentages are seen on the scintigrams after total amputation of an extremity followed by replantation without anastomosing of interrupted lymph vessels. 相似文献
67.
Charles E. Wenner John C. Cheney L. David Tomei 《Journal of cellular biochemistry》1981,15(2):161-168
The introduction of either PGF2α (10?7 M) or TPA (10?7 M) stimulated, ouabain-sensitive 86Rb+ influx at 30 min in postconfluent 3T3-4 mouse fibroblast cultures by 117% and 124%, respectively. Both TPA and PGF2α at these concentrations stimulated the incorporation of 3H-TdR into DNA. TPA had the greatest stimulatory effect, which was similar to that obtained with 10% fetal calf serum. In accord with the idea that modulation of membrane processes such as Na+/K+ pump activity in fibroblasts may reflect important events related to the initiation of DNA synthesis, it was observed that in both 3T3-4 and C3H-1 0T½ cells there were parallel increases in 3H-TdR incorporation and ouabain-sensitive 86Rb+ influxes with 10?7 M TPA, whereas PGF2α stimulated a significant increase in 3H-TdR incorporation in 3T3-4 but not C3H-10T½ cells and only marginal increases in ouabain-sensitive 86Rb+ influx in both. Therefore, although there appears to be a close correlation between Na+/K+ pump activation and subsequent S-phase entry following TPA stimulation, a similar correlation for PGF2α cannot be confirmed. 相似文献
68.
69.
Cellular response to oxidative stress at sulfhydryl group receptor sites on the erythrocyte membrane 总被引:6,自引:0,他引:6
J Reglinski S Hoey W E Smith R D Sturrock 《The Journal of biological chemistry》1988,263(25):12360-12366
Ellman's reagent was used to induce an oxidative stimulus on the exofacial membrane sulfhydryl groups of the human erythrocyte. Thiol-disulfide exchange occurring extracellularly was monitored using resonance Raman spectroscopy, and intracellular changes were observed by 1H spin echo nuclear magnetic resonance spectroscopy of the intact cell. The stimulus caused oxidation and depletion of the glutathione pool, which was followed at higher concentrations of Ellman's reagent by a depletion of intracellular ergothioneine levels. Larger changes are induced intracellularly than would be expected from the stoichiometry of the reaction at the exofacial surface. A mechanism is proposed which links exofacial sulfhydryl receptor sites via the transport proteins to spectrin and glutathione. The consequences for the cellular redox balance of an extracellular stimulus of this type are discussed. 相似文献
70.
R L Allen R Hopewell C Prottey 《Comparative biochemistry and physiology. B, Comparative biochemistry》1986,84(4):523-529
Histidine ammonia lyase was purified to homogeneity from guinea-pig liver and epidermis. Both enzymes had similar molecular weights, subunit composition and pH optima. Km values for the two were similar at pH 9.2 but different at pH 7.0. Both enzymes were stimulated by low thiol concentrations and inhibited at higher concentrations, but to different extents. Antibody to the hepatic enzyme showed complete identity against hepatic enzyme but incomplete identity against epidermal enzyme. 相似文献