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941.
942.
A reliable method was developed for the quantitative determination of two nuclear polyhcdrosis viruses present in commercially prepared viral insecticides used against Orgyia pseudotsugata. Deoxyribonucleic acids, from nuclear polyhedrosis bundle virus and nuclear polyhedrosis single-rod virus, were separated on CsCl gradients according to their respective buoyant densities, 1.715 and 1.704 g/ml. The proportions of the two viruses were quantified by measuring the relative absorbance at 254 nm of their deoxyribonucleic acid peaks.  相似文献   
943.
The microtubules associated with the pellicle, reservoir and locomotory flagellum of Euglena granulata were subjected to rotational analysis using the technique of Markham et al. The results indicate that the microtubules have 11-14 subunits when viewed in transverse section. Rotational analysis of the entire locomotory flagellum was also conducted to better demonstrate the nature of the arms extending from the peripheral microtubules.  相似文献   
944.
In these studies we describe the production of three mAb raised to an idiotype on an IgG anticasein antibody isolated from the serum of one IgA-deficient blood donor. These are IgM kappa and block the binding of casein Ag to anticasein antibody. Sera of unrelated IgA-deficient donors were tested for the presence of the idiotype; 15 of 56 IgA-deficient sera (25%) contain the anticasein idiotype, whereas 1 of 45 normal sera was positive. Anticasein antibodies as a whole were predominantly of the IgG1 and IgG3 subclass; idiotype-positive anticaseins are predominantly of the IgG1 subclass. For IgA-deficient donors, the relative amount of idiotype-positive anticasein antibody was correlated with the level of anticasein present in the serum. Studies were done to investigate the potential inheritance of the idiotype in families; in three of four families the idiotype was inherited in an apparent autosomal dominant pattern. Our data show that a common cross-reactive idiotype can be detected in the sera of IgA-deficient individuals and their family members. This suggests that V region markers may be conserved in this humoral immunodeficiency disease.  相似文献   
945.
The nisin resistance determinant and an origin of replication on pNP40, a plasmid of about 60 kilobases that is present in Streptococcus lactis subsp. diacetylactis DRC3, was cloned on a 7.6-kilobase EcoRI fragment. When self-ligated, this fragment existed as an independent replicon (pFM011) and contained a 2.6-kilobase EcoRI-XbaI fragment encoding nisin resistance.  相似文献   
946.
G Gaál  E Bácsy  G Rappay 《Histochemistry》1988,88(3-6):401-406
Cultured cells from the anterior pituitary glands of adult rats were treated with the tripeptide aldehyde proteinase inhibitor, BOC-DPhe-Phe-Lys-H. The addition of this tripeptide aldehyde decreased the in vitro release of prolactin to 25% of the control value, while the release of growth hormone in the same cultures decreased to 33% of the control value. Prolactin immunostaining was stronger in semithin sections of proteinase-inhibitor-treated cultures than in control sections. After 2 h treatment with the inhibitor, prolactin- and growth hormone-containing secretory granules were numerous, and the number of crinophagic vacuoles had increased. In the presence of the inhibitor, the overall cytoarchitecture of parenchymal cells was well preserved, and the pathway of the uptake of cationic ferritin appeared to be unaffected.  相似文献   
947.
948.
949.
A maltose-induced major outer membrane protein (the 44K protein) is demonstrated in Salmonella typhimurium. This protein resembles the lambda receptor of Escherichia coli in its location, induction properties, apparent molecular weight, and association with the peptidoglycan layer of the cell wall. The 44K protein is missing in certain Salmonella Mal- mutants, which are also missing a protein analogous to the maltose-binding protein of E. coli. Thus, these mutants may be defective in the control of maltose genese in Salmonella. The proteins appear to be closely related, as indicated by cross-reaction of the Salmonella protein with the antiserum raised against the lambda receptor; however, they are not identical, since the peptide patterns obtained after limited proteolysis are completely different. Bacteriophage lambda does not use the 44K protein as a receptor.  相似文献   
950.
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