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41.
Development of nephrotic ICGN mice--the origin, reproductive ability, and incidence of glomerulonephritis 总被引:1,自引:0,他引:1
A Ogura T Asano J Matsuda Y Noguchi Y Yamamoto K Takano M Nakagawa 《Jikken dobutsu》1989,38(4):349-352
ICGN is a strain of spontaneous nephrotic mice with nonproliferative glomerular lesions. It was derived from an outbred Yok: ICR colony in our laboratory. The renal disease constantly occurred in animals of the first to the tenth generations (greater than 13.0%; 70 days of age). When affected males were mated with unaffected females, the incidence of the disease in their offspring was 38.8% (n = 49) at 70 days after birth. When both parents were affected, their offspring were all affected (n = 12). The disease evenly progressed in both sexes. It usually began 40 to 150 days after birth and death occurred within two months after onset. The animals usually showed sufficient reproductive ability as long as unaffected females were used for mating. 相似文献
42.
N Yamamoto M M Rahman M Fukushima K Maeno Y Nishiyama 《Biochemical and biophysical research communications》1989,158(1):189-194
Cyclopentenone prostaglandin (PG), delta7-PGA1 was found to induce several polypeptides in human embryonic fibroblast (HEF) cells which were noticed to be dose-related and appeared after 1 h of treatment with a peak at around 5 h and gradual disappearance after 12 h. PG-induced proteins were almost identical in terms of molecular weights with those induced by heat-shock at 42 degrees C. Regarding the mechanism of inhibition of herpes simplex virus (HSV) replication by PG in cell culture, dot blot hybridization has revealed that the level of immediate early (IE) mRNA of the virus was reduced after PG treatment with time dependence. And this delayed inhibitory effect of delta7-PGA1 on HSV was shown to be associated with the production and accumulation of the induced polypeptides. 相似文献
43.
Biologically active Low-molecular-weight, chromium-binding substance (LMCr) has been isolated from the liver of rabbits injected with potassium bicarbonate and cow's milk. This substance enhances glucose oxidation and lipogenesis from glucose in rat adipocytes [Yamamoto A. et al. (1987) Eur. J. Biochem. 165, 627-631; (1988) J. Nut. 118, 39-45]. LMCr was shown to lose its activity almost completely as an effectant of glucose metabolism when Cr was deleted under acidic conditions and separated from LMCr by EDTA-chelation and successive molecular-sieve chromatography. Reincorporation of Cr3+ into apo-LMCr resulted in 50-90% recovery of its original activity. These findings suggest that the biological activity of LMCr resides in Cr. 相似文献
44.
H Yoshiyama T Kajii N Yamamoto N Kobayashi 《Biochemical and biophysical research communications》1989,158(3):973-979
The rate of multinucleated giant cell formation by the fusion of HIV chronically infected human T-cells (MOLT-4/HIV) and HIV uninfected MOLT-4 cells was examined under various pH conditions. The number of giant cells formed under the different pH conditions was quantitatively monitored by "MULTISIZER". The rate of giant cell formation was significantly less at the pH lower than 6 but not influenced at higher pH. Plaque assay under various pH conditions revealed that inhibition of giant-cell formation at lower pH was not due to the influence over the recognition between gp120 of HIV and CD4 molecules. 相似文献
45.
46.
Quantitation and immunohistochemical localization of cathepsins E and D in rat tissues and blood cells 总被引:2,自引:0,他引:2
The distribution of cathepsins E and D in various rat tissues and blood cells was determined by immunoprecipitation and by immunohistochemistry with discriminative antibodies specific for each enzyme. While cathepsin D was detected in all of the tissues and blood cells tested (except for erythrocytes), cathepsin E had a relatively limited distribution. The cathepsin E content was highest in the stomach and was succeeded in the following order by the urinary bladder, thymus, spleen, cervical lymph node and bone marrow. Significant amounts of cathepsin E were also found in the colon, rectum, jejunum, skin, lung, kidney and submandibular gland. The other tissues tested had little or no detectable cathepsin E content. Of the blood cells tested, lymphocytes and peritoneal neutrophils contained high levels of cathepsin E. Erythrocytes had cathepsin E only as aspartic proteinases. When the subcellular localization of cathepsin E in the neutrophils was investigated by fractionation of the postnuclear supernatants, the enzyme behaved as a soluble cytosolic enzyme. In contrast, cathepsin D was mainly associated with the granular fraction. The immunohistochemical localization of cathepsins E and D was clearly different in the stomach, large intestines, kidney and urinary bladder, but was similar in the lymph node and spleen. The tissue-fixed macrophages, which were notable in the skeletal and cardiac muscle tissues, submucosal layers of the gastrointestinal tracts, salivary gland, lung and trachea, also exhibited similar intense immunoreactivities demonstrative of both cathepsins E and D. 相似文献
47.
To determine the relative contribution of mate access and environmental cues in stimulating egg-laying and plasma luteinizing hormone (LH) secretion in cockatiels (Nymphicus hollandicus), and of mate access on nest-inspection and bowl-formation, mated pairs were permitted different degrees of mate access (full contact, auditory plus visual contact, auditory contact only, or no contact) and sequentially exposed to three environmental conditions (8L:16D without nest-box access for 6 weeks; 15L:9D without nest-box access for 3 weeks; 15L:9D with nest-box access for 3 weeks). The results indicate that a high degree of mate access is essential for the performance of nesting behaviors, since birds allowed no mate access or only auditory mate access were significantly less likely to inspect the nest or form a nest-bowl. Furthermore, pairs permitted no contact, auditory contact only, or auditory and visual contact delayed nest-inspection and bowl-formation and were significantly less likely to lay eggs than pairs with total mate contact. LH levels were significantly elevated only in photostimulated females of pairs of permitted full mate and nest-box access. These results suggest that maximal sexual activity in cockatiels requires an array of behavioral and environmental cues and that a linear relationship exists between extent of social cues and sexual activity. 相似文献
48.
M Sato H Tsuchiya M Kato K Yamamoto G Nakazato N Takagi I Namikawa 《The International journal of biochemistry》1989,21(7):751-754
1. Both Tween 80 and sodium fluoride significantly enhanced total extracellular glucosyltransferase activities of Streptococcus mutans. 2. Water-insoluble and water-soluble glucan formation were uniformly increased by Tween 80, whereas fluoride stimulated only water-soluble glucan formation. 3. Elevated glucan formation was due to an increase in enzymes secreted from bacterial cells. 4. Fatty acid composition and phospholipid content in bacterial membrane were changed by Tween 80, although sodium fluoride scarcely showed these changes. 5. Comparative results suggest that modulation of membrane lipids participates in mutansucrase production but not in dextransucrase production of S. mutans. 相似文献
49.
The mesencephalic reticular formation (MRF) neurons are regarded as contributing to the activation of the celebral cortex. In this paper, the statistical features of single neuronal activities in MRF of cat during dream sleep are investigated; the neuronal spike train exhibits 1/f fluctuations. Counting statistics is applied to the neuronal spike train giving rise to a variance/mean curve which follows at
-law. For an interpretation of these findings, the clustering Poisson process is applied which not only gives rise to at
-law but also suggests a generation mechanism. The MRF neuronal activities are closely fitted by the clustering Poisson process and the underlying statistical parameters can be estimated. These findings strongly suggest that neuronal activities can be interpreted as superposition of randomly occuring clusters ( = bursts of spikes). 相似文献
50.
E Yabuuchi I Yano H Oyaizu Y Hashimoto T Ezaki H Yamamoto 《Microbiology and immunology》1990,34(2):99-119