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11.
Antigens associated with various cytotoxic activities of murine peripheral macrophages 总被引:1,自引:0,他引:1
BCG- or glucan-elicited murine peripheral macrophages released a cytotoxin in the presence of loach egg lectin, whereas proteose peptone-, glycogen-, or thioglycollate-elicited or resident macrophages did not. The macrophages that released cytotoxin coincided with those that showed lectin-dependent macrophage-mediated cytolysis (LDMC) in response to loach egg lectin. The cytotoxin released by BCG-elicited macrophages in response to loach egg lectin had a molecular weight of 55 K daltons. The macrophages that released cytotoxin and other cytotoxic macrophages such as those that showed LDMC- and antibody-dependent macrophage-mediated cytolysis (ADMC) were examined by using several antibodies to surface antigens of macrophages. The results showed that murine peripheral macrophages could be divided into three types. Resident macrophages (Type I) which had common macrophage antigens (Mac-1 and B12) showed only LDMC in response to wheat germ agglutinin. Some elicited macrophages (Type II) were asialo GM1-positive and showed both ADMC and LDMC in response to wheat germ agglutinin. Activated macrophages (Type III) showed LDMC in response to loach egg lectin and cytotoxin-release, but had no antigen detectable with monoclonal anti-macrophage antibody (C14). These three types of macrophages were clearly distinguished diagrammatically by their roof-shaped, rocket-shaped and irregular-shaped profiles of activities and antigens. These data suggest that several selected surface antigens of macrophages are associated with distinct cytotoxic stages of peripheral macrophages. 相似文献
12.
Peroxisomes from spinach leaves containing enzymes related to glycolate metabolism 总被引:51,自引:0,他引:51
N E Tolbert A Oeser T Kisaki R H Hageman R K Yamazaki 《The Journal of biological chemistry》1968,243(19):5179-5184
13.
M Sakaguchi S Inouye H Miyazawa H Kamimura M Kimura S Yamazaki 《Laboratory animal science》1989,39(3):234-236
Laboratory animal allergy is a serious occupational diseases of many workers and scientists engaged in animal experimentation. Control measures depend upon characterization of allergens including airborne particles. This study measured the particle size of crude mouse urine and pelt aeroallergens generated in mouse housing rooms and compared them with mouse serum albumin, a defined major allergen. Allergens were detected by specific immunological methods. Most crude and defined allergens (74.5-86.4%) concentrated on a filter with a retention size greater than 7 microns. In distrubed air, allergen concentration increased 1.4 (albumin) to 5 (crude) fold and the proportion of small particles increased from 1.4% in calm air to 4.5% in distrubed air. This information on the generation and size distribution of aeroallergens will be important in the development of effective counter measures. 相似文献
14.
Eiji Nitasaka Tsuneyuki Yamazaki M. M. Green 《Molecular genetics and genomics : MGG》1995,247(2):164-168
A large proportion of spontaneous mutations inDrosophila melanogaster strains of laboratory origin are associated with insertions of mobile DNA elements. As a first step toward determining whether spontaneous laboratory mutations are predictive for mutational events occurring in the wild, recessivebrown (bw) eye color mutants were isolated. By inbreeding the progeny of wild-caughtDrosophila melanogaster females,bw mutations were isolated from seven separate geographic sites distributed among Japan, California, Siberia and Hungary. Among a total of 14 mutations studied, no case of transposon mutagenesis was found. At least 4 mutations are associated with small deletions in thebw gene. The remainder are inseparable from wild-typebw by Southern analysis and are presumed to be basepair changes or very small indels. Although only two spontaneousbw mutants of laboratory origin have been analyzed molecularly, one is a mobile element insertion. 相似文献
15.
Fumio Yamazaki Ryoko Sone Nobuharu Fujii Haruo Ikegami 《International journal of biometeorology》1993,37(4):212-217
Based on the hypothesis that the relation between sweating rate and body temperature should be different during exercise and rest after exercise, we compared the sweating response during exercise and recovery at a similar body temperature. Healthy male subjects performed submaximal exercise (Experiment 1) and maximal exercise (Experiment 2) in a room at 27° C and 35% relative humidity. During exercise and recovery of 20 min after exercise, esophageal temperature (Tes), mean skin temperature, mean body temperature (
), chest sweating rate (
), and the frequency of sweat expulsion (F
SW) were measured. In both experiments,
andF
SW were clearly higher during exercise than recovery at a similar body temperature (Tes,
).
was similar during exercise and recovery, or a little less during the former, at a similarF
SW. It is concluded that the sweating rate during exercise is greater than that during recovery at the same body temperature, due to greater central sudomotor activity during exercise. The difference between the two values is thought to be related to non-thermal factors and the rate of change in mean skin temperature. 相似文献
16.
K Miyamura K Yamashita S Yamadera N Kato M Akatsuka M Hara S Inouye S Yamazaki 《Japanese journal of medical science & biology》1992,45(4):203-214
This report presents an overall distribution of poliovirus isolations in Japan, where poliomyelitis has been under control over two decades as a result of legal administration of two doses of the trivalent live oral poliovirus vaccine of the Sabin strains (OPV) to children under 48 months of age. During the past 12 years from 1980 through 1991, a total of 1,126 poliovirus isolations from humans and 268 isolations from sewage/river water were reported by respectively 49 and nine of the participating laboratories. Type 2 was most frequently isolated from children after administration of one dose of OPV, followed by type 1 and type 3. On the contrary, after the second dose of OPV, the rate of isolation of type 3 exceeded those of type 2 and type 1. Seasonal and age distribution of poliovirus isolations from both humans and sewage/river water paralleled the OPV vaccination schedule in Japan. One percent of the isolations were, however, from infants younger than the vaccination-scheduled ages and 5% were from children older than those ages, including one each from 15 and 16 years olds. The data indicate that the poliovirus has silently been disseminated from vaccinated children to others and the community, thus suggesting repeated transmission of the viruses. The fact that some elder children had poliovirus colonization in their alimentary tracts indicates a potential risk of infection of such a population when exposed to a wild virus and of becoming a source of transmission to others. 相似文献
17.
K Yamazaki A Kumazawa K Ito K Kurihara M Nakayama T Wakabayashi 《Laboratory animal science》1992,42(4):378-381
Senescence-accelerated mice (SAM) are one of the animal models used for studying senescence, which consist of several substrains such as SAM-R/1, R/2, P/1, P/2. SAM-R/1/Eis maintained in Eisai Tsukuba Research Laboratories, Ibaraki, Japan, was originally introduced as a substrain of a normal control SAM-R/1 from Kyoto University, Japan. We have noted signs of convulsions in SAM-R/1/Eis mice during routine animal care, particularly while changing cages. We identified the clinical signs and determined the concentrations of glucose and immunoreactive insulin in plasma of SAM-R/1/Eis mice. There were no differences in the male:female ratios of mice showing prodrome only, grand mal, or no-signs. The ages at which prodrome and grand mal were first noted peaked between 20 and 25 weeks. Concentrations of glucose and immunoreactive insulin in plasma did not indicate the mice were in insulin hypoglycemia, which is one cause of convulsions. AKR strain mice, some of which originated with the SAM strain are known to become convulsive by repeated "throwing" stimulations. Conversely, in SAM-R/1/Eis, throwing stimuli are not needed to cause convulsive signs. Thus it is likely that in SAM-R/1/Eis mice the signs are triggered by repeating mild environmental changes, such as changing cages. The results of this study show that SAM-R/1/Eis is neither a normal control strain, nor an original SAM-R/1 strain. But it is possible that SAM-R/1/Eis is another useful animal model for studying spontaneous convulsion. 相似文献
18.
The stability of oxyperoxidases increased in the order meso- < proto < chlorocruoro- < diacetylperoxidases, which was an increasing order of electron-withdrawing capacities of 2,4-substituents of deuteroheme and the ratio of Δlogk1toΔpK3 was approximately 0.6 in the two series of isoenzyme preparations, horseradish peroxidases A and (B + C), where k1andpK3 represent a rate constant for conversion from an oxyperoxidase to the ferric enzyme and a measure of basicity of pyrrole nitrogen of the substituted deuterohemes, respectively. Deutero-oxyperoxidases A and (B + C) were definitely more stable than expected from the above linear relationship. The stability of peroxidase Compound I also varied with the 2,4-substituents, but it did not necessarily correlate with electron-withdrawing capacities of the substituents. Natural peroxidases formed relatively stable Compound I in both series of the isoenzymes. From these results it was concluded that the stability of oxyperoxidases was affected by the electron density at the iron atom of the enzyme while steric factors might be involved in stabilizing Compound I. 相似文献
19.
20.