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81.
R Yabe  M Bannai  K Nakata  T Seno  Y Okubo  H Yamaguchi 《Blut》1989,59(2):157-161
Subgroups of type A blood, named A1, A2, and A1-A2 intermediate (Aint), are specifically characterized by their peculiar A alleles and have their own A1-, A2- or Aint-forms of alpha-N-acetyl-D-galactosaminyltransferase (A-transferase). It is known, however, that certain type A2B persons exhibit A1-transferase. The reason may be an unusual alpha-galactosyltransferase (B-transferase). This strong B-transferase competes with A-transferase for the substrate, H antigen, so as to decrease the A and H antigens on the red cells. We studied this blood group over three generations and found that the strong B-transferase is, in fact, inherited with the B gene and is dominant over normal B-transferase. In AB blood groups in Tokyo, the frequency of people with a strong B-transferase is 5% for A1B and 22% for A2B. This enzyme does not always cause weak H or A antigens.  相似文献   
82.
Summary The role of various iron chelators on the multiplication of mouse hybridoma cells in an albumin-free, transferrin-deficient defined medium was investigated. Fe(III)-dihydroxyethylglycine, Fe(III)-glycylglycine, Fe(III)-ethylenediamine-N,N′-dipropionic acid, or Fe(III)-iminodiacetic acid supported the excellent growth of the cells. In addition, the growth of the iron-starved cells, which had been preincubated in a protein-, iron- and chelator-free defined medium, restored rapidly when the medium was supplemented with holotransfeerrin, ferric iron, and chelator compared to that when supplemented with holotransferin, but without iron and chelator. The results suggest that such chelators modulate a progression of transferrn cycle in the presence of transferin and ferric iron. An alternative explantation is that there is a decrease in generation of iron-catalyzed free radicals.  相似文献   
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Vital statistics on the breeding through successive generations were presented for the cynomolgus monkey colony of NIH, Tokyo. The results of this retrospective survey clearly demonstrated the third (F2) and the fourth (F3) generations could be bred and reared successfully by the indoor caged-breeding system in which either individual timed-mating or group mating procedure was adopted. Several important and difficult problems involved in the production of successive generations of the cynomolgus monkey by our breeding system were discussed from the standpoint of laboratory animal science.  相似文献   
85.
Summary We describe a genetic polymorphism of human lymphocyte cytosol major polypeptide with mol. wt. 64,000, detected in peripheral blood lymphocytes by high resolution two-dimensional electrophoresis. Three different electrophoretic types (1-1, 2-1, 2-2) of the polypeptide have been identified. Family and population studies indicate that the three phenotypes of the polypeptide are determined by two common alleles at a single autosomal locus. The polypeptide occurs in the cytosol and is predominent in peripheral blood lymphocytes, B-lymphoblastoid cells, T-lymphoblastoid cells, lymph node, and spleen. The polypeptide has not been detected in HeLa cells, fibroblasts, erythrocytes, serum, and cerebrum. Traces of the polypeptide exist in liver, kidney, and skeletal muscle. It is proposed that the polypeptide and its locus be temporarily designated lymphocyte cytosol 64K polypeptide (LC64K polypeptide) andLC64P, respectively. In a Japanese population, the gene frequencies ofLC64P 1 andLC64P 2 were 0.936 and 0.064, respectively. The data suggest thatLC64P is a new locus, product of which shows genetic polymorphism and is associated with the function and/or the structure of lymphocytes.  相似文献   
86.
The circadian rhythm of gastric content, serum alkaline phosphatase (alk.P.), serum lipids, body weight (wt), relative (rel.) liver wt, cellular structures (by light- and electron-microscopy), mitotic activity of hepatocytes, glycogen content, protein and lipids in liver was studied in 180 male Sprague-Dawley rats orally treated at 0830-1030 with 50 mg/kg phenobarbital (PB) for 7 days. Thereafter, five PB-treated males and five controls each were studied at 4-hr intervals at 0600, 1000, 1400, 1800, 2200 and 0200 on 3 consecutive days. The lighting schedule in the colony was 12:12 = light/dark (light from 0600 to 1800). Following the rhythm of gastric emptying, the rel. liver wt showed a clear circadian rhythm with a peak at 0800. The rel. liver wt was raised in PB-treated rats at all times of the day. The circadian rhythm of cellular structures was closely related to the hepatic glycogen content which exhibited a clear rhythm with the peak also at 0800, but lowered values were found in PB-treated rats. The mitotic activity of hepatocytes was significantly increased in PB-treated rats but displayed the same circadian rhythm as controls with peaks at noon and troughs at midnight. The well-known hypertrophy of the smooth endoplasmic reticulum in PB-treated rats was not found at 0600, but was fully developed at 1400 and 2200. PB-treatment increased significantly the liver content of cholesterol, triglycerides and phospholipids. Liver cholesterol showed a clear circadian rhythm with peaks at 1800. No rhythm of liver protein, triglycerides and phospholipids was observed. In serum, levels of cholesterol were significantly elevated, those of triglycerides and alk.P. significantly lowered, while those of phospholipids were not affected by the treatment. The three serum lipids, alk.P. and beta-lipoprotein exhibited a clear circadian rhythm, while serum glucose and non-esterified fatty acids did not.  相似文献   
87.
RCAI-84, 91, and 105-108 (1-6), the analogs of KRN7000 (A) with a ureido or a thioureido linkage instead of a carboxamido bond, were synthesized to examine their immunostimulatory activity against mouse lymphocytes. According to their bioassay, the ureido analog of KRN7000 [RCAI-105 (1)] and its 6'-O-methylated derivative [RCAI-106 (4)] induced a large amount of IFN-γ in mice in vivo. The hexadecyl ureido analog [RCAI-84 (2)] was comparable to KRN7000 in its bioactivity. The octylureido [RCAI-107 (3)], 5-phenylpentylureido [RCAI-108 (5)], and thioureido [RCAI-91 (6)] analogs were almost inactive.  相似文献   
88.
Liposuction aspirates (primarily saline solution, blood, and adipose tissue fragments) separate into fatty and fluid portions. Cells isolated from the fatty portion are termed processed lipoaspirate (PLA) cells and contain adipose-derived adherent stromal cells (ASCs). Here we define cells isolated from the fluid portion of liposuction aspirates as liposuction aspirate fluid (LAF) cells. Stromal vascular fractions (SVF) were isolated separately from both portions and characterized under cultured and non-cultured conditions. A comparable number of LAF and PLA cells were freshly isolated, but fewer LAF cells were adherent. CD34+ CD45- cells from fresh LAF isolates were expanded by adherent culture, suggesting that LAF cells contain ASCs. Although freshly isolated PLA and LAF cells have distinct cell surface marker profiles, adherent PLA and LAF cells have quite similar characteristics with regard to growth kinetics, morphology, capacity for differentiation, and surface marker profiles. After plating, both PLA and LAF cells showed significant increased expression of CD29, CD44, CD49d, CD73, CD90, CD105, and CD151 and decreased expression of CD31 and CD45. Multicolor FACS analysis revealed that SVF are composed of heterogeneous cell populations including blood-derived cells (CD45+), ASCs (CD31- CD34+ CD45- CD90+ CD105- CD146-), endothelial (progenitor) cells (CD31+ CD34+ CD45- CD90+ CD105low CD146+), pericytes (CD31- CD34- CD45- CD90+ CD105- CD146+), and other cells. After plating, ASCs showed a dramatic increase in CD105 expression. Although some adherent ASCs lost CD34 expression with increasing culture time, our culture method maintained CD34 expression in ASCs for at least 10-20 weeks. These results suggest that liposuction-derived cells may be useful and valuable for cell-based therapies.  相似文献   
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90.
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