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31.
Change in the localization of the antigen recognized by the proteinuria-inducing monoclonal antibody (MA) 5-1-6 in experimental nephrosis was studied by indirect and biotin-avidin immunofluorescence, and immunoperoxidase at light and electron microscopical levels. The proteinuric state was induced by the administration of the aminonucleoside of puromycin (PAN) or adriamycin. The antigen decreased in quantity and/or its distribution changed with an increase in the amount of protein excreted in both experimental models. Recovery from the alterations observed during the development and proteinuria appeared to occur when PAN-induced proteinuria subsided. This antigenic molecule may thus be essential for maintaining the normal permselectivity of glomerular capillary walls.  相似文献   
32.
Using a single-probe method, we have cloned the gene for an immunogenic MPB57 protein of Mycobacterium bovis BCG. The nucleotide sequence includes an ORF of 300 base pairs encoding a protein of 99 amino acids with an Mr of 10,818. This cloned gene was expressed in an Escherichia coli expression vector to give a mature protein which reacted with a polyclonal antibody raised against MPB57.  相似文献   
33.
34.
Cytochrome c oxidase of Nitrosomonas europaea reacts with not only the native cytochrome c (N. europaea cytochrome c-552) but also horse and yeast cytochromes c. The effects on its reactivity of various reagents were very different between the reactions with the native and eukaryotic cytochromes c as the electron donors. The oxidation of eukaryotic ferrocytochrome c by the oxidase was activated by addition of anionic detergents such as sodium dodecyl sulfate and sodium cholate, and anionic phospholipids such as cardiolipin, phosphatidylserine, phosphatidylinositol, and phosphatidylethanolamine, while the reaction was not activated by Triton X-100, Tween 20, or phosphatidylcholine. However, the reaction with the native cytochrome c of the enzyme was hardly affected by any of the detergents and phospholipids mentioned above, while it was activated by the presence of poly-L-lysine.  相似文献   
35.
The anticoccidial activity of an uridine analog, 1-(beta-D-ribofuranosyl)-2(1H)-pyrazinone 4-oxide (emimycin riboside), against five species of chicken Eimeria was tested individually in battery experiments. With 16 ppm of the compound in feed, marked anticoccidial activity was obtained against Eimeria tenella, E. necatrix, E. acervulina, E. maxima, and E. brunetti. The last named species was more drug-sensitive than the others--dietary levels of at least 8 ppm of the drug exhibited good protection and eliminated practically all clinical signs. The battery tests with delayed and restricted medications showed that emimycin riboside affected the development of parasites in first and second generation schizogony of the life cycle of E. tenella.  相似文献   
36.
Circadian variations in the activities of aldehyde dehydrogenase (ALDH) isozymes in the subcellular fractions of the brain and liver were investigated in male and female mice of C57BL/6J strain. The rhythms in high Km-ALDH activities of brain and liver mitochondrial fractions which existed in ordinary light-dark cycle were not observed in animals maintained in the continuous darkness for two weeks. The rhythms in high Km-ALDH activities of hepatic soluble and microsomal fractions existed in both ordinary cycle and total darkness but the rhythmic phases were different. In the low Km-ALDH activity of hepatic mitochondrial fraction, the circadian rhythm was similar in two lighting conditions. There was sex difference in the existence of the circadian rhythm. It seems that the ALDH activity of mice is influenced by light-dark cycle and sex hormones.  相似文献   
37.
Release of cytotoxin by macrophages on treatment with human placenta lectin   总被引:1,自引:0,他引:1  
Human lectin purified from placenta induced release of cytotoxin from a murine macrophage cell line and human peritoneal monocytes. This activity was not due to contamination of the lectin preparation with lipopolysaccharide.  相似文献   
38.
Spectra of chloroperoxidase compounds II and III   总被引:2,自引:0,他引:2  
Chloroperoxidase was present as Compound II during the peroxidatic oxidation of ascorbic acid. Compound III (oxy-form) was formed when excess hydrogen peroxide was added to Compound II. By decreasing the temperature it was possible to measure the spectra of Compounds II and III in the Soret and visible regions. Each spectrum was found to resemble that of the corresponding form of lactoperoxidase. Under the experimental conditions, chloroperoxidase Compound III was apparently converted to Compound II in parallel with the decomposition of hydrogen peroxide and finally to the ferric enzyme.  相似文献   
39.
Studies were made by electron microscopy (EM) on the viruses associated with diarrhea of outpatients at a pediatric clinic in Osaka Prefecture during the three year period from 1980 through 1982. The viruses detected by EM by negative staining with phosphotungstic acid (PTA) were classified morphologically into 6 groups: rotavirus, adenovirus and four kinds of small spherical viruses, calicivirus, astrovirus, picornavirus/parvovirus (P/P)-like agent and Osaka-agent. Osaka-agent seems to be a newly identified small virus. It is 35-40 nm in diameter with a fringe of spike-like structures on its surface. Viruses were detected in 181 of the 395 cases of diarrhea (45.8%). Rotavirus was detected in 122 (30.9%) of the total cases and in 67.4% of the virus-positive cases, while other viruses were detected in 15% of the total cases; adenovirus in 23 (6%) and small agents in 36 (9%). Rotavirus infection showed a distinctive seasonal variation, being mainly restricted to cooler months, but infections with other viruses did not show any seasonal variation. The age distribution of patients suggested that infants of 0 to 2 years old are very susceptible to all viruses. Attempts to cultivate these viruses in vitro were successful with only two isolates of adenovirus type 5.  相似文献   
40.
The genotoxicity of N-nitrosodipropylamine, 8 of its oxidized derivatives and N-nitroso-2,6-dimethylmorpholine was examined in the hepatocyte primary culture (HPC)/DNA repair test. Nine N-nitrosamines which are known to be carcinogenic and mutagenic were clearly positive in the HPC/DNA-repair test. N-Nitroso(2,3-dihydroxypropyl) (2-hydroxypropyl)amine did not elicit DNA repair, but showed a borderline mutagenic response in the Salmonella/microsome test. Thus, the HPC/DNA-repair test displays a comparable capacity to the bacterial mutagenesis test for detecting the genotoxic effects of this class of carcinogens.  相似文献   
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