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41.
C Kubo B C Johnson N K Day R A Good 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1992,201(2):192-199
Chronic energy (calorie) intake restriction (CEIR) prolonged life, inhibited autoimmune disease, and influenced immunologic and hematologic parameters in NZB mice. Abnormalities in numbers and proportions of T and B cells populations were corrected. Deficient responses to phytomitogens, mixed lymphocyte reactions, formation of plaque-forming cells to sheep red blood cells in vitro, production of cytotoxic T lymphocytes after in vitro stimulation, and interleukin 2 production were also corrected. CEIR prevented the extreme splenomegaly that normally occurs with age in NZB mice. This influence was associated with reduction of a greatly expanded non-T, non-B lymphoid cell population. Calorie restriction also prevented in NZB mice the rapid decrease in total numbers of colony-forming B cells in bone marrow that is also characteristic of mice of this strain. The influences of CEIR on immune parameters and hematopoiesis were generally less marked in non-autoimmune-prone DBA/2 mice than in autoimmune-prone NZB mice. CEIR has been shown to produce profound influences on several strains of autoimmune-prone mice (NZB x NZW)F1, MRL/lpr, BXSB, and NZB herein). In each of these strains, the pathogenesis and manifestations of autoimmune disease are dissimilar. Therefore, it seems likely that calorie restriction acts on an as yet elusive mechanism that operates to foster development of the diseases associated with aging common to each of these autoimmune strains as well as autoimmune-resistant mice and rats. Further investigation of the molecular and cellular bases of the benefits of CEIR seems urgent. 相似文献
42.
43.
F M Salzano F L Black S M Callegari-Jacques S E Santos T A Weimer M A Mestriner R R Kubo J P Pandey M H Hutz 《American journal of physical anthropology》1991,85(1):51-60
Data on 31 genetic systems were obtained for 421 individuals belonging to the Arara, Araweté, Mundurucu, and Jamamadi tribes of northern Brazil. The Jamamadi depart farthest, and the Mundurucu least, from South American Indian averages. These data are analyzed together with those of 24 other Amazonian groups. Genetic distances and corresponding dendrograms indicate a cluster of 14 related tribes living north of the Amazon river. These genetic results show only a modest correlation with linguistic and geographic relationships among these groups. 相似文献
44.
Y Hirabayashi T Inoue K Yoshida H Sasaki S Kubo M Kanisawa M Seki 《International journal of cell cloning》1991,9(1):24-42
Five cases of murine leukemia with megakaryocytic differentiation were observed among the 417 cases of radiation-induced leukemias which developed in 30% of C3H/HeMs mice exposed at 8 to 10 weeks to 0.5 to 5 gy total body irradiation. Cells from individual leukemic colonies in the spleen of the irradiated mice, and cells from colonies in methylcellulose (MC) culture in vitro, derived from one of these leukemias, MK-8057, were injected into mice; both types of cells caused the deaths of the recipient mice by inducing the same type of leukemia. MK-8057 can be maintained in Dexter-type liquid culture with a feeder layer of irradiated bone marrow cells. There was a linear reciprocal relationship between the increasing number of MK-8057 cells injected versus the survival of the recipient mice. A reciprocal relationship also was seen between an increasing number of leukemic stem cells, corresponding to the number of MK-8057 cells, and the survival of mice injected with MK-8057. Giant nuclear megakaryocytes developed during the course of colony growth in the spleen as they did in the MC culture. Such megakaryocytes were acetylcholinesterase positive, whereas leukemic cells in the peripheral blood showed no sign of platelet production nor of a positive reaction to acetylcholinesterase. Cells maintained in culture were entirely positive in platelet glycoprotein IIb/IIIa when anti-human antibody was used. The larger cells in a splenic cell suspension derived from a moribund mouse were separated and enriched by velocity sedimentation using centrifugal elutriation (CE), and then subjected to flow cytometry using propidium iodide staining. Cells with up to 32N-DNA content were detected. After separating MK-8057 by counter-flow CE, the larger cell fraction (mode at 540 microns3) produced more leukemic colonies when injected into irradiated mice than did the small cell fraction (mode at 240 microns3). A higher percent of the larger cell fraction (61.9%) was killed by the addition of tritiated thymidine cytocide than in the smaller cell fraction (14.9%). Thus, the smaller cell fraction is considered to have more leukemic spleen colony-forming units (L-CFU-s) in the resting state. 相似文献
45.
A novel method for the reconstitution of oxygen evolution in cholate-extracted spinach thylakoid membranes was established and a protein essential for the reconstitution was purified from cholate extracts. Purification of the protein was accomplished by chromatography on a DEAE-Sephacel column. This protein (Mr 17 000) was reinserted into vesicular membranes reconstituted from cholate-extracted thylakoids in the presence of 25% glycerol to reactivate oxygen evolution. 相似文献
46.
47.
M Kubo H Akashi Y Inaba M Osada S Konno 《National Institute of Animal Health quarterly》1982,22(2):45-53
One- to 21-day-old mice were examined pathologically after inoculated intracerebrally or subcutaneously with the Kakegawa strain of bovine coronavirus. In 1- to 4-day-old mice inoculated intracerebrally, the brain contained a small number of neutrophils and lymphocytes having infiltrated diffusely and perivascularly and some degenerative neurons. In mice inoculated intracerebrally at 7 to 21 days of age, severe necrosis of pyramidal cells was shown in Ammon's horn. Perivascular infiltrations of neutrophils and lymphocytes were moderate to severe. Some neurons were degenerative in the cerebral cortex, thalamus and midbrain. Degeneration of some neurons and mild infiltration of neutrophils and lymphocytes were observed in the brain of mice inoculated subcutaneously at 1 to 7 days of age. Perivascular infiltration of neutrophils and lymphocytes was prominent in the cerebral cortex of mice inoculated subcutaneously at 14 days of age. Cellular infiltration was also seen in the thalamus, Ammon's horn, midbrain, cerebellum and medulla oblongata. All the mice, except one, inoculated subcutaneously at 21 days of age were free from neural changes. Electron-microscopically, virus particles were observed in and outside of the degenerative neurons. They had a core 70 nm in diameter and an envelope with spikes. 相似文献
48.
Yoshinori Asakawa Masao Toyota Reiji Takeda Claude Suire Tsunematsu Takemoto 《Phytochemistry》1981,20(4):725-728
Riccardia species (Metzgeriales) contain various types of sesquiterpenes. R. jackii produces ent-selinane-, ent-aromadendrane-and ent-bicyclogermacrane-type sesquiterpenes together with (R)-cuparene and α-barbatene. Aneura pinguis (= Riccardia pinguis) is chemically quite different from R. multifida and R. jackii. The former produces a large amount of pinguisone. R. multifida contains 6-(3-methyl-2-butenyl)-indole and (+)-β-elemene as the major components. Pallavicinia longispina (Dilaenaceae; Metzgeriales) produces mainly spathulenol. The chiral properties of the sesquiterpenes isolated from R. jackii are quite similar to those of red algae, Laurencia species. 相似文献
49.
A new bibenzyl having a dihydrooxepin ring was isolated from the acetone extract of the liverwort Radula tokiensis, together with the previously known 5 bibenzyls and 3 sesquiterpenes, trans-β-farnesene, cuparene and (Jcuparenol. Two known bibenzyls were isolated from R. japonica. The bibenzyl derivatives are significant chemosystematic markers of the Radulaceae. 相似文献
50.