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71.
72.
Miss S. Dobrofsky Dr. W. F. Grant 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1980,58(2):157-160
Summary A study of seed position in the pod ofLotus corniculatus L. cv. Mirabel (Fabaceae) suggested that reduced seed set after self-pollination is not due to an inability of the self-pollen tube to reach the end of the ovary. As in other cultivars, it has been demonstrated that cultivar Mirabel produced less seed per pod and shorter pods after self- than after cross-pollination. No differences were noted for percent germination of seeds produced by both types of pollination indicating that the number of seeds per pod is a reliable index of the ultimate productive potential of the pollination. 相似文献
73.
D O Thueson L S Speck M A Lett-Brown J A Grant 《Journal of immunology (Baltimore, Md. : 1950)》1979,123(2):626-632
Supernatants from 1- to 2-day cultures of human mononuclear cells induced the release of histamine from basophils. Generation of this histamine-releasing activity (HRA) was stimulated by addition of concanavalin A to the cell cultures. Mononuclear cells were also cultured with SKSD and Candida albicans antigens. Stimulation of HRA production by these antigens was correlated with positive delayed skin reactions. Serial dilutions of supernatants assayed for HRA provided a semiquantitative determination of the level of HRA in mitogen- or antigen-stimulated samples. Antigen increased HRA production when added during the first or second day of culture. Generation of HRA probably requires active protein synthesis, since puromycin was inhibitory, and since preformed HRA could not be recovered from lysed cells. HRA was detected in supernatants after 4 hr, and the effects of antigen stimulation were apparent after 8 hr of culture. Replacement of supernatants with fresh culture medium allowed continued synthesis of substantial quantities of HRA during the second day of culture. A linear correlation was observed between the amount of HRA produced and the mononuclear cell concentration. Our findings provide evidence for the interaction of lymphocytes and basophils via a soluble mediator. 相似文献
74.
Summary
PI phenotypes (including subtypes) were determined for 168 individuals with chromosomal abnormalities ascertained in Adelaide. These included patients with mosaicism, trisomy 21, trisomy 13, trisomy 18, and various sex chromosome aberrations (45,X, 47,XXX, 47,XXY, 47,XYY, and 48,XXXY). Data did not support an existing proposition that mildly deficient PI phenotypes predispose to abnormal chromosome segregation during mitosis or meiosis. Phenotypic distributions of each group were statistically similar to control populations of cord bloods and bloods donors. 相似文献
75.
The serum half-life of bovine [3H]acetyltrypsin was estimated to be 9 rain following intravenous administration in rats. This was maintained when six successive doses of 200 g each were given at 1-h intervals. The enzyme was removed from the circulation after complexing with 2-macroglobulin (2-M). The amount of3H label appearing in bile increased with each successive dose and this was associated with breakdown products (<10 000 daltons) of the 2–M/[3H] acetyltrypsin. Intact –M/[3H] acetyltrypsin was recovered from bile but represented only 0.06% of the administered dose of active enzyme. 相似文献
76.
Johannes F. Imhoff Brian J. Tindall William D. Grant Hans G. Trüper 《Archives of microbiology》1981,130(3):238-242
A new phototrophic bacterium was isolated from Jordanian and Kenyan alkaline salt lakes. Cells are rod shaped, 1.5 m wide and 2–4 m long, and motile by polar flagella. They divide by binary fission, and possess photosynthetic membranes as lamellar stacks similar to those in the other species of the genus Ectothiorhodospira and the brown colored Rhodospirillum species. The presence of bacteriochlorophyll a and carotenoids of the normal spirilloxanthin series is indicated by the absorption spectra of living cells. Under certain growth conditions the cells form gas vacuoles, may become immotile and float to the top of the culture medium. Sulfide and thiosulfate are used as photosynthetic electron donors. During the oxidation of sulfide to sulfate, elemental sulfur is formed, which is accumulated outside the cells. The organisms are strictly anaerobic, do not require vitamins, are moderately halophilic and need alkaline pH-values for growth. The new species Ectothiorhodospira vacuolata is proposed. 相似文献
77.
Some observations on the choice of detergent for solubilization of the human erythrocyte membrane. 总被引:1,自引:0,他引:1 下载免费PDF全文
Solubilization of the human erythrocyte membrane by seven detergents is described. Components released into the supernatant or retained in the residue were identified by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. Two non-ionic detergents exhibiting little u.v. absorption were more efficient than u.v.-absorbing Triton X-100. Evidence is presented of an interchange between protein PAS 1 and protein PAS 2. 相似文献
78.
Enzyme-linked immunosorbent analysis for aflatoxin B1. 总被引:1,自引:0,他引:1
An enzyme-linked immunosorbent analysis (ELISA) permitted the detection of less than 10 pg of aflatoxin B1 per ml. The antitoxin was most specific for aflatoxins B1 and B2alpha, and least specific for aflatoxin G1. 相似文献
79.
Chromosome damage in Chinese hamster cells sensitized to near-ultraviolet light by psoralen and angelicin 总被引:1,自引:0,他引:1
The clastogenic effect of furocoumarins psoralen and angelicin in the presence of near-UV (320-380 nm) differs greatly, as do their modes of interaction with DNA. Psoralen, which requires only one-fifth as much light energy to produce the same lethal effect as angelicin at equimolar concentrations, is able to cross-link DNA whereas angelicin cannot. The frequency of micronuclei which arise from chromosomal fragments shows the same differential effect as lethality. Indeed aberrations account for much or all of the lethality observed. Metaphase analysis at comparable aberration frequencies revealed that angelicin and psoralen both induce chromatid deletions and a wide spectrum of chromatid exchanges. These data show that both cross-links and monoadducts to the DNA can result in chromosomal aberrations. The relative contributions of cross-links and monoadducts to chromosomal aberrations still remain to be determined. It is noteworthy that extensive chromosomal damage is induced in mammalian cells by the combination of psoralen and near-UV, a treatment which is currently widely used in the therapy of psoriasis. 相似文献
80.