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11.
H Izumi  S Hayashi  K Karita 《Life sciences》1988,42(16):1529-1535
The effects of subcutaneous (s.c.) administration of compound 48/80 (a well known histamine liberator) on latency to thermoalgesic stimulus, hematocrit (Hct) and plasma levels of beta-endorphin-like immunoreactivity (beta-END-LI) were investigated in male rats. The s.c. administration of compound 48/80 in doses ranging from 0.5 to 5.0 mg/kg into the rats produced significant analgesia in the hot plate test and increased Hct in a dose-dependent manner. Concomitant variation was observed between the analgesia and the increase of Hct. This analgesic effect, but not the increase of Hct, was diminished by pretreatment with the opiate receptor antagonist, naloxone (5 mg/kg, s.c.). A significant increase of plasma beta-END-LI was observed by s.c. injection of compound 48/80. Together with a previous finding that compound 48/80 induced-hypovolemia increases the renin release from kidney and then causes water intake in the rats, it is suggested that s.c. administration of compound 48/80 induced analgesia mediated through stimulation of an opioid system, may be closely related to stimulation of the renin-angiotensin system.  相似文献   
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A major plasma protein, referred to as SP 1, exhibits sex- and stage-specific expression during the larval development of the silkworm, Bombyx mori. We have isolated a plasmid clone bearing a part of mRNA sequence coding for SP 1 and quantitated the amount of SP 1 mRNA by means of RNA blot hybridization using the cDNA probe. The developmental change in the amount of SP 1 mRNA in the fat body closely reflected that of the hemolymph concentration of SP 1, indicating that the biosynthesis of SP 1 is regulated in a sex- and developmental stage-specific fashion at the level of mRNA.  相似文献   
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Non-cycling pluripotent bone marrow stem cells (CFU-S), taken 3 hrs after injection of 20 mg of Ara-C, have been shown to enter DNA synthesis at 1 to 3 hr after being cultured in alpha-medium. This phenomenon was observed when bone marrow was incubated as a plug, but not when incubated as a cell suspension in the present experimental conditions. These results suggest that a medullary structure is necessary in order to observe this effect and/or that accessory cells are destroyed during the process of single cell preparation.  相似文献   
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Activity of a chymotrypsin-type serine protease was found in a subline of rat basophilic leukemia (RBL-2H3) cells. The protease was immunologically cross-reactive with anti-atypical mast cell protease immunoglobulin (Ig) G, and its activity was inhibited in a dose-dependent manner by the antibody. The apparent m.w. of the protease that reacted with the antibody was 25,000, which was identical with that of atypical mast cell protease in rat mucosal mast cells. These results show that the chymotrypsin type serine protease in RBL-2H3 cells is immunologically identical with atypical mast cell protease, which was first purified from rat small intestine. Immunohistochemical studies showed that the protease was located not only in intracytoplasmic granules but also in organelles synthesizing protein, such as cisternae of the rough endoplasmic reticulum, perinuclear spaces, and the Golgi apparatus. However, no immunoreactivity was demonstrated in rat basophils. The activity of the protease increased in the exponential phase of growth of RBL-2H3 cells in which some activity was also detected in the medium, and it decreased in the late stationary phase.  相似文献   
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In a high-volume cytology laboratory in the metropolitan Tokyo area, the incidence of cytologically diagnosed herpes infection in cervical scraping smears of the female genital tract was studied according to the year-by-year changes, age distribution, seasonal variation and types of cytologic alteration. The overall incidence over the 12 years studied was 0.007% (87 cases among 1,230,773 examined). The incidence varied from 0.003% to 0.005% in the early 1970s (except for 1973) and increased to 0.011% in the last three years (1980 to 1982). A large increase was noted in younger age groups in comparison with middle and older age groups. There was a tendency for the infection rate to be higher in the spring (0.011%) and lower in the fall (0.005%). Multinucleation and a ground-glass appearance were observed in the infected cells in almost every case while eosinophilic inclusion bodies were found in 20.7% of the cases.  相似文献   
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It has been suggested that the O-side chains of the lipopolysaccharide (LPS) of serotype 0:3 strains of Yersinia enterocolitica vary quantitatively and qualitatively depending on whether they are cultured at 37 degrees C or 25 degrees C. It is uncertain whether this affects the expression of the serotype-specific antigens that are probably carried on the LPS. We studied this question with a serotype 0:3-specific monoclonal antibody, 2C1. This monoclonal antibody immunoprecipitated a 39K major protein from detergent-solubilized 125I-labeled Yersinia preparation. However, results of Western blot experiments demonstrated that the antigens reactive with 2C1 were not actually the 39K protein but the O-side chains of the LPS. Significantly, reactivity could be detected whether the bacteria were cultured at room temperature or at 37 degrees C. However, absorption experiments confirmed that there were less accessible antigenic determinants on the 37 degrees C-LPS. The LPS preparations were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and silver staining. These SDS-PAGE profiles showed that less O-side chains were present in the 37 degrees C-LPS. Hence, the most likely explanation for our observation is that the 37 degrees C incubation condition induced a partial smooth to rough transition of the Yersinia LPS with a decrease in the amount of 2C1-reactive antigen.  相似文献   
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