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41.
42.
Van Vleck Chambers 《The Western journal of medicine》1960,93(4):211-216
A study was carried out to determine whether the double diffusion gel test when applied to the serum of patients with clear-cut penicillin reactions of various types, might be useful for demonstrating the presence of precipitating antibody. Results did not demonstrate the antibody.The difference in results with this test obtained by various workers was not explained by the observations in this study.Other approaches to determination of the mechanism of the penicillin reaction are discussed, and it is noted that the hemagglutination test, newly applied to the penicillin reaction problem, may be useful after further investigation. 相似文献
43.
Disinfection of Aerosolized Pathogenic Fungi on Laboratory Surfaces: II. Culture Phase 总被引:2,自引:0,他引:2 下载免费PDF全文
Richard H. Kruse Theron D. Green Richard C. Chambers Marian W. Jones 《Applied microbiology》1964,12(2):155-160
The effect of several fungicides on laboratory surfaces contaminated with the culture (spore) phase of aerosolized Blastomyces dermatitidis, Coccidioides immitis, and Histoplasma capsulatum was ascertained. The culture (spore) phase was more resistant to the action of the fungicides than was the tissue (yeast) phase. The addition of a wetting agent increased the efficiency of several fungicides. The time required for disinfection with a given concentration of fungicide, or the concentration required to disinfect within a given time, can be determined by interpolating the plotted graphs. 相似文献
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A novel succinyl dipeptide stimulates directed cell migration by modulating protein kinase C activity 总被引:1,自引:0,他引:1
R N Mascardo W Thompson M A Gallo T C Chambers G Eilon 《Journal of cellular physiology》1990,142(2):401-409
In determining the mechanism of the chemokinetic action of the thiol protease inhibitor, E-64, in endothelial cell monolayers subjected to wounding, we synthesized succinyl-leucyl-agmatine (SLA), an analogue of E-64 that lacked the epoxy group and protease inhibitory effect. We observed that this analogue retained its chemokinetic effect on wounded endothelial cells. Its stimulatory action on endothelial cell polarization response to wounding was rapid and associated with directed cell migration. Furthermore, its effect on cellular polarization was blocked by protein kinase C (PKC) inhibitors and mimicked by pharmacologic agents that stimulated PKC activity. To determine if SLA's chemokinetic action was mediated by protein kinase C activation, we compared the effects of SLA and the tumor promoter phorbol myristate acetate (PMA) on the translocation of PKC activity in endothelial cells. We observed that both SLA and PMA induced the translocation of PKC activity from the cytosolic to the particulate fraction of the cells. We also observed that both SLA and PMA induced the phosphorylation of two proteins (Mr 23.4 and 36.5 kDa) in intact 32P-labeled cells. Thus, SLA stimulates the endothelial cell locomotor response to wounding by stimulating PKC activity. 相似文献
47.
Evidence for distinguishable transcripts of the putative testis determining gene (ZFY) and mapping of homologous cDNA sequences to chromosomes X,Y and 9 总被引:10,自引:3,他引:7 下载免费PDF全文
48.
Same-day batch measurement of glycine betaine, carnitine, and other betaines in biological material. 总被引:3,自引:0,他引:3
Glycine betaine, carnitine, carnitine esters, butyrobetaine, and proline betaine (stachydrine) concentrations in biological materials can be reliably measured in 100-microliters samples, with a detection limit below 1 mumol/liter. The procedure is suitable for batches of more than 30 specimens and it is possible to obtain a single result within 2 h. The betaines are extracted into an acetonitrile:methanol mixture, dried with anhydrous disodium hydrogen phosphate containing argentous oxide. The 4-bromophenacyl ester derivatives are formed using 4-bromophenacyl triflate as reagent, in the presence of solid magnesium oxide as base. The derivatives are separated by high-performance chromatography on a silica column, in a mixed partition and ion-exchange mode. 相似文献
49.
Basement membrane-degrading enzymes of two clonal sublines of the murine Lewis lung carcinoma with distinct patterns of organ-selective metastasis were analyzed. Subline M-27 is highly metastatic to the lung and does not form liver metastases, while subline H-59 is highly metastatic to lymph nodes and liver, but not to lung. Qualitative and quantitative differences in the enzymatic profiles were found. H-59 cells which were significantly more invasive in vitro in the Matrigel invasion assay were found by zymogram analysis to secrete high levels of a 72 kDa gelatinase, while M-27 cells produced low levels of this gelatinase and of a higher molecular weight species which migrated in the 107 kDa region. On the other hand, M-27 cells produced significantly higher levels of urokinase type plasminogen activator (uPA) as indicated by a fibrinolysis assay and by Western blot analysis. Northern blot assays revealed an increase of approx. 3-fold in mRNA for cathepsin B in tumor M-27 which was reflected in a quantitative difference in plasma membrane cathepsin B levels as detected by Western blot analysis. H-59 cells on the other hand expressed approx. 8.5-fold more mRNA for cathepsin L. The quantitative differences in the levels of basement membrane degrading proteinases released by these tumor cells suggest that invasion by these cells is differentially regulated--a possible factor in their distinct patterns of dissemination. 相似文献
50.
X J Guo A F Chambers C L Parfett P Waterhouse L C Murphy R E Reid A M Craig D R Edwards D T Denhardt 《Cell growth & differentiation》1990,1(7):333-338
A mouse mRNA, provisionally designated 5B10, has been cloned based on its inducibility by serum in quiescent murine fibroblasts. Here we report the full-length complementary DNA sequence and a partial characterization. There are about five copies of the gene in the mouse genome. Sequence analysis of the 5B10 coding region reveals 94 and 97% amino acid identity to human and rat calcyclin, respectively. Although the coding region has been highly conserved during evolution of the rodent and human genomes, the untranslated flanking sequences differ significantly. A protein of Mr about 8000 was produced by in vitro translation of the mRNA transcribed in vitro from 5B10 complementary DNA in a riboprobe vector. An antiserum raised against a portion of the predicted human calcyclin protein cross-reacted with this mouse protein. 5B10 mRNA was found in greatest amount in organs containing proliferating cells, e.g., epidermis, skin, stomach, uterus of pregnant mouse, placenta, and decidua. Brain, liver, mature thymus, and skeletal muscle had little or no detectable 5B10 mRNA. 5B10 mRNA levels were higher in cells treated with 7,12-dimethylbenzanthracene and 12-O-tetradecanoylphorbol-13-acetate than in their normal counterparts, suggesting a role in tumorigenesis. In addition, high 5B10 mRNA levels were associated with metastatic ability in a series of ras-transformed cells, in proportion to levels of ras p21 expressed by the cells, implicating 5B10 even more deeply in carcinogenesis. 相似文献