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61.
Diane S. Herson Balkumar Marthi Mary Anne Payer Dr. Katherine H. Baker 《Current microbiology》1986,13(2):77-80
Direct microscopic enumeration ofEnterobacter cloacae with the acridine orange 2-(p-iodophenyl)-3-(p-nitrophenyl)-5-phenyl tetrazolium chloride technique (AOINT) was compared with spread plate counts on nonselective media to establish the usefulness of the former technique in the enumeration of chlorine-stressed cells. Results indicate that the techniques are comparable when the organisms are not stressed. However, AOINT is more sensitive than are plate counts in the detection of chlorine-stressed cells. 相似文献
62.
Amino acid sequence homology between rat prostatic steroid binding protein and rabbit uteroglobin 总被引:2,自引:0,他引:2
M E Baker 《Biochemical and biophysical research communications》1983,114(1):325-330
Using a computer program designed to detect evolutionary relationships between proteins, I find that the polypeptide chain of rabbit uteroglobin has amino acid sequence homology with the C1 and C2 polypeptide chains of rat prostatic steroid binding protein. Using this finding I suggest several interesting approaches for studying the biology of these proteins. 相似文献
63.
Paul E. Baker Anita Hagemo Kenneth Knoblock J.P. Dubey 《Experimental parasitology》1983,55(3):320-330
Using a sensitive, economical, and reproducible microassay, the relationship of toxoplasma inhibiting factor to interleukin 2 has been examined. The assay developed took advantage of the observation that (1) Toxoplasma gondii tachyzoites replicated efficiently in the murine monocytic cell line, RAW 264; (2) treatment of RAW 264 cells with toxoplasma inhibiting factor prevented intracellular replication of the parasite to an extent similar to that observed with identical treatment of freshly isolated murine peritoneal exudate cells; and (3) [3H]uracil incorporation was an efficacious means to quantify replication (or inhibition of replication) of tachyzoites within the cell line. Although toxoplasma inhibiting factor and interleukin 2 were both present in the same lectin -and antigen-stimulated splenocyte supernatant fluids, results from microassays strongly suggested that the molecules were two distinct entities. 相似文献
64.
Longevity of Salmonella typhimurium in Tilapia aurea and water from pools fertilized with swine waste. 总被引:1,自引:1,他引:0 下载免费PDF全文
Salmonella typhimurium declined rapidly when inoculated into Tilapia aurea culture pools fertilized with fresh swine waste. Within the water column, a 95% decline of viable cells occurred during the first 6 h. Isolation of viable salmonellae was possible at 16 days post-inoculation, but not at 32 days. Similarly, salmonellae could be detected in the viscera and epithelium of T. aurea at 16 days, although not at 32 days. Salmonellae were not isolated from the fish flesh, nor was there evidence of septicemic infection. 相似文献
65.
Identification of a monoclonal antibody that specifically recognizes corneal and skeletal keratan sulfate. Monoclonal antibodies to cartilage proteoglycan 总被引:25,自引:0,他引:25
Monoclonal antibodies were raised against proteoglycan core protein isolated after chondroitinase ABC digestion of human articular cartilage proteoglycan monomer. Characterization of one of the monoclonal antibodies (1/20/5-D-4) indicated that it specifically recognized an antigenic determinant in the polysaccharide structure of both corneal and skeletal keratan sulfate. Enzyme immunoassay analyses indicated that the mouse monoclonal IgG1 recognized keratan sulfate in native proteoglycan aggregate and proteoglycan monomer preparations isolated from hyaline cartilages of a wide variety of animal species (human, monkey, cow, sheep, chicken, and shark cartilage). The 1/20/5-D-4 monoclonal antibody did not recognize antigenic determinants on proteoglycan isolated from Swarm rat chondrosarcoma. This finding is consistent with several biochemical analyses showing the absence of keratan sulfate in proteoglycan synthesised by this tissue. A variety of substructures isolated after selective cleavage of bovine nasal cartilage proteoglycan (Heineg?rd, D., and Axelsson, J. (1977) J. Biol. Chem. 252, 1971-1979) were used as competing antigens in radioimmunoassays to characterize the specificity of the 1/20/5-D-4 immunoglobulin. Substructures derived from the keratan sulfate attachment region of the proteoglycan (keratan sulfate peptides) showed the strongest inhibition. Both corneal and skeletal keratan sulfate peptides as competing antigens in radioimmunoassays showed similar inhibition when compared on the basis of their glucosamine content. Therefore, the 1/20/5-D-4 monoclonal antibody appears to recognize a common determinant in their polysaccharide moieties. Chemical desulfation of the keratan sulfate reduced the antigenicity of the glycosaminoglycan. The antibody did not recognize determinants present in dermatan sulfate, heparin, heparin sulfate, or hyaluronic acid. 相似文献
66.
Heritable fragile sites on human chromosomes. X. New folate-sensitive fragile sites: 6p23, 9p21, 9q32, and 11q23 总被引:3,自引:1,他引:2 下载免费PDF全文
Four new folate-sensitive fragile sites are documented at 6p23, 9p21, 9q32, and 11q23. These have all been shown to be heritable except for the one at 9p21, which has been seen only in a single individual. As with the other autosomal fragile sites, these appear to be innocuous in heterozygotes. 相似文献
67.
68.
Summary Exudate can be obtained from incisions made in the bark of the stem of actively growing Ricinus plants. 14C-labelled assimilates from a fed leaf are rapidly detected in the exudate. This movement was both acropetal and basipetal from the fed leaf, at rates of over 100 cm h-1. Estimated rates within intact plants were 80–84 cm h-1.In contrast with xylem sap obtained from the same plant, the exudate obtained had an alkaline pH (8.2), a high dry matter content (10–12.5%), high sugar content (8–10%) which was predominantly sucrose; high potassium content (60–80 mM) and low calcium content (0.5–1.0 mM).It is concluded, on the basis of the present evidence, that the exudate is a true sample of the sieve tube sap undergoing translocation. 相似文献
69.
Grey seals on the West Hoyle Bank feed on a variety of fish and have a high incidence of dermal lesions, often associated with emaciation and nematode parasite infection. Corynebacterium phocae has been isolated from an active lesion. The significance of large numbers of seals in the Dee Estuary bearing lesions is discussed and the occurrence of seals with lesions elsewhere in British waters is reviewed. No evidence was found to associate the dermal lesions with any environmental factor and it is probable that lesions develop as a result of infection of minor wounds. 相似文献
70.