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A separate and distinct population of polyribosomes exists in the detergent-washed nuclei of adenovirus-infected HeLa cells. These polyribosomes, released by exposure to polynucleotides such as high molecular weight nuclear RNA or poly(U), do not appear to be cytoplasmic contaminants. Nuclear polyribosomes have a considerably lower buoyant density compared to cytoplasmic ones. Nuclear polyribosomes, in a cell-free system of protein synthesis, are six- to eight-fold less active compared to cytoplasmic ones and are insensitive to aurin tricarboxylic acid. They do not complement cytoplasmic polyribosomes in protein synthesis in the cell-free system. Finally, the number of proteins synthesized by nuclear polyribosomes is higher compared with that synthesized by the cytoplasmic ones. Only the virus-specific proteins, including P-VII, are synthesized by cytoplasmic polyribosomes. Nuclear polyribosomes, on the other hand, synthesize virusspecific proteins, including P-VII and VII, and a number of additional proteins not synthesized by the cytoplasmic ones.  相似文献   
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In three patients with juvenile rheumatoid arthritis, serum IgA concentrations were within the normal limit at the onset of disease and before aspirin administration. After aspirin administration, their serum IgA levels gradually decreased. After discontinuation of aspirin, their serum IgA levels gradually increased. These results suggest that IgA deficiency may be due to aspirin administration in such patients. The IgA production in vitro of peripheral blood mononuclear cells from a patient taken 3 months of discontinuation of aspirin was markedly inhibited by preincubation with aspirin. Since the patients' serum IgG and IgM levels hardly changed the heavy chain class switching may be influenced by aspirin through some undefined mechanisms.Abbreviations CH heavy chain constant region - 3H-TdR 3H-thymidine - Hepes N-2-hydroxyethyl-piperazine-N-2-ethanesulfonic acid - JRA juvenile rheumatoid arthritis - MEM minimum essential medium - PBMCs peripheral blood mononuclear cells - PBS phosphate buffered saline - PFCs plaque forming cells - PWM pokeweed mitogen - SI stimulation index  相似文献   
185.
Summary Sphingomyelinase activity in cultured skin fibroblasts from a fetus affected with infantile-type Niemann-Pick disease was 0.5% of control activity; the activities in cells from two patients with adult-type disease (Cases 2 and 3) were 5.0% and 59.0%.Sphingomyelinase activity was separated into three peaks (I–III) by isoelectric focusing. The isoelectric points were 4.5, 4.9, and 5.2 for peaks I, II, and III, respectively. The three peaks in the Case 2 cells were drastically reduced; only a very small peak could be distinguished (pI of 4.7). On the other hand, three peaks were observed in the Case 3 cells. Peak I had a pI of 4.4, peak II a pI of 4.7, and peak III a pI of 5.2. Peak I was found at near normal level, but both peaks II and III were markedly reduced.Sphingomyelinase in the peak I fraction obtained from isoelectric focusing in Case 3 cells was found to have the same Km value as that in control cells.  相似文献   
186.
Polyarteritis nodosa (PN), characterized by vasculitis of medium and small sized arteries, is uncommon in children. This disease is thought to be concerned with some abnormal immune responses. Platonin (4,4'-dimethyl-3,3'-di-n-heptyl-8-[2-(4-methyl-3-n-heptylthiazole) ]-2,2'- dicarbocyanine diiodine) is one of the photosensitive dyes of trithiazole pentamethine cyanine. It has been reported that platonin stimulated suppressor/cytotoxic T cells, but suppressed B cells. In clinical observations, platonin is shown to be efficacious for rheumatoid arthritis and juvenile rheumatoid arthritis. In this study, a Japanese boy (9-year-old) with PN was given platonin in combination with prednisolone. Prednisolone was gradually tapered under a cover of platonin. As a result, the relapse has not been exhibited for a long time (72 months). There were no adverse side effects during long term administration of medication.  相似文献   
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Addition of NaHSO3 or HCN to the formyl group of heme alpha was greatly accelerated by freezing reaction mixtures prepared in aq. Na2CO3, and freezing resulted in characteristic color and spectral changes of the solutions. Similar changes were observed on decreasing the pH of alkaline reaction mixtures with HCl at room temperature, indicating that the effective pH of certain salt solutions is greatly lowered by freezing. The reactivity of the formyl group changed depending on the redox state of the heme iron and the species of ligand.  相似文献   
190.
The incidence of Listeria monocytogenes contamination in raw milk from farm bulk tanks and silage was investigated monthly at 20 dairy farms in Aomori prefecture, Japan, from January to July in 1989. Listeria sp. was isolated from one sample (5%) of raw milk collected in May, but L. monocytogenes was not isolated from raw milk. L. monocytogenes was isolated from two samples of silage (10%) collected in June. Silage, cow feces, sawdust bedding, dust and soil in these farms were tested for listerias, and we confirmed listerias contamination of the environment in the dairy farms.  相似文献   
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