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21.
We previously demonstrated that a tumor cytotoxic factor(F-TCF) purified from the culture broth of human embryonic lung diploid fibroblast, IMR-90 cells was one of the human hepatocyte growth factors (hHGFs). In the present report, we demonstrate its biological functions. F-TCF showed moderate cytotoxicity on human tumor cell lines KB, BG-1, MCF-7 and Hs913 T, and strong cytotoxicity on mouse tumor cell lines Sarcoma 180, Meth A sarcoma and P388. On the contrary, F-TCF was a potent mitogen not only for adult rat hepatocytes, but also for human endothelial cells, HUVEC and human melanocytes. Moreover, F-TCF induced the differentiation of premyelocyte leukemia, HL-60 cells into morphologically granulocyte-like cells. These biological functions suggest that F-TCF is an effector molecule responsible for inflammation and repair in injured tissues including tumor and liver.  相似文献   
22.
Genetic polymorphism of human serum ribonuclease I (RNase I).   总被引:1,自引:1,他引:0       下载免费PDF全文
One of the human urinary ribonucleases (RNases) was isolated and purified to homogeneity (SDS-PAGE) by means of a series of column chromatographies. The enzyme, designated RNase 1, is a glycoprotein with a molecular weight of approximately 16,000. Rabbit antibody to the purified RNase 1 reacted with human urine and sera, as well as with the purified RNase 1. The genetic polymorphism of serum RNase 1 was studied by polyacrylamide gel isoelectric focusing (IEF-PAGE) in a pH range of 5-8, followed by immunoblotting with antisera specific for RNase 1. Two common phenotypes, RNASE1 1 and RNASE1 1-2, were easily recognized. The homogeneous phenotype, RNASE1 1, consisted of four major bands with different pI values, and the heterogeneous phenotype, RNASE1 1-2, was presumed to represent a mixture of each of the homogeneous phenotypes 1 and 2; however, the other homogeneous phenotype, RNASE1 2, was not detected in our samples. Family studies are in agreement with an autosomal codominant transmission of the two alleles. Population studies indicate that the frequencies of the RNASE 1 and RNASE1 2 alleles are .988 and .012, respectively.  相似文献   
23.
A ribonuclease (RNAase) was isolated and purified from the urine of a 45-year-old man by column chromatographies on DEAE-Sepharose CL-6B, cellulose phosphate and CM-cellulose followed by gel filtrations on Bio-Gel P-100 and Sephadex G-75, and finally to a homogeneous state by SDS-polyacrylamide gel electrophoresis. The enzyme was designated RNAase 1. It was possible to detect RNAase 1 isozymes in urine and serum without difficulty using isoelectric focusing electrophoresis followed by immunoblotting with a rabbit antibody specific to RNAase 1. The existence of genetic polymorphism of RNAase 1 was detected in human serum utilizing this technique (Yasuda, T. et al. (1988) Am. J. Hum. Genet., in press). RNAase 1 in serum and urine seemed to exist in multiple forms with regard to molecular weight and pI value. Genetically polymorphic RNAase 1 was a glycoprotein, containing three mannose, one fucose, four glucosamine and no sialic acid residues per molecule, with a molecular weight of 16,000 and 17,500 determined by gel filtration and SDS-polyacrylamide gel electrophoresis, respectively. The enzyme was most active at pH 7.0 on yeast RNA substrate and inhibited remarkably by Cu2+, Hg2+ and Zn2+. It also showed definite substrate preference for poly(C) and poly(U), but much less activity against poly(A) and poly(G). Thus, the enzyme is a pyrimidine-specific RNAase.  相似文献   
24.
Summary Plants from agricultural and natural upland ecosystem were investigated for15N content to evaluate the role of symbiotic N2-fixation in the nitrogen nutrition of soybean. Increased yields and lower δ15N values of nodulating soybeansvs, non-nodulating isolines gave semi-quantitative estimates of N2 fixation. A fairly large discrepancy was found between estimations by δ15N and by N yield at 0 kg N/ha of fertilizer. More precise estimates were made by following changes in plant δ15N when fertilizer δ15N was varied near15N natural abundance level. Clearcut linear relationships between δ15N values of whole plants and of fertilizer were obtained at 30 kg N/ha of fertilizer for three kinds of soils. In experimental field plots, nodulating soybeans obtained 13±1% of their nitrogen from fertilizer, 66±8% from N2 fixation and 21±10% from soil nitrogen in Andosol brown soil; 30%, 16% and 54% in Andosol black soil; 7%, 77% and 16% in Alluvial soil, respectively. These values for N2 fixation coincided with each corresponding estimation by N yield method. Other results include: 1)15N content in upland soils and plants was variable, and may reflect differences in the mode of mineralization of soil organics, and 2) nitrogen isotopic discrimination during fertilizer uptake (δ15N of plant minus fertilizer) ranged from −2.2 to +4.9‰ at 0–30 kg N/ha of fertilizer, depending on soil type and plant species. The proposed method can accurately and relatively simply establish the importance of symbiotic nitrogen fixation for soybeans growing in agricultural settings.  相似文献   
25.
We analyzed glycosphingolipids from normal lymph node cells of seven cattle and lymph node cells of eight cattle with enzootic bovine leukosis. The neutral glycosphingolipids and gangliosides were analyzed by thin-layer chromatography. Both normal and tumorous lymph node cells had GlcCer, LacCer, and GbOse3Cer as major neutral glycosphingolipids. In the ganglioside fraction, GM3 was the predominant component in both normal and tumorous lymph node cells, and another component, ganglioside Gx fraction, was also prominent in tumorous lymph node cells. The structure of this ganglioside Gx fraction was elucidated by thin-layer chromatography, sugar analysis, neuraminidase digestion, and permethylation studies. This ganglioside Gx fraction was found to be a mixture of four ganglioside species. The structures of individual gangliosides Gx (1 to 4) were characterized as follows. 1: GD3, NeuAc alpha 2-8NeuAc alpha 2-3Gal1-4Glc-Cer. 2: GD3, NeuAc alpha 2-8NeuGc alpha 2-3Gal1-4Glc-Cer. 3: GD3, NeuGc alpha 2-8NeuAc alpha 2-3Gal1-Glc-Cer. 4: GD3, NeuGc alpha 2-8NeuGc alpha 2-3Gal1-4Glc-Cer. These GD3 species may be formed as a result of the induced synthesis inassociation with malignant transformation.  相似文献   
26.
H1 phosphorylation has been studied through the precise nuclear division cycle of Physarum polycephalum. The number of sites of phosphorylation of Physarum H1 is very much larger than the number of sites reported for mammalian H1 molecules which is consistent with the larger molecular weight of Physarum H1. At metaphase all of the Physarum H1 molecules contain 20-24 phosphates. Immediately following metaphase, these metaphase-phosphorylated H1 molecules undergo rapid dephosphorylation to give an intermediate S phase set of phosphorylated H1 molecules containing 9-16 phosphates. Progressing into S phase newly synthesized H1 is phosphorylated and eventually merges with the old dephosphorylated H1 to give a ladder of bands 1-20. By the end of S phase or early G2 phase, there is a ladder of bands 1-16 all of which undergo phosphate turnover. Further into G2 phase the bands move to higher states of phosphorylation, and by prophase all of the H1 molecules contain 15-24 phosphates which increases to 20-24 phosphates at metaphase. These results support the proposals that H1 phosphorylation is an important factor in the process of chromosome condensation through G2 phase, prophase to metaphase.  相似文献   
27.
The toxic effect of aluminum (Al) on the growth of Carrot cells(SO-l) decreased to a greater degree with addition of a mediumconditioned by Al-tolerant carrot cells (TA-l) than with a mediumconditioned by SO-l cells. The toxic effect of Al was reducedgreatly by adding an acidic fraction of the conditioned media,but little or not at all by a neutral or basic fraction. Offour organic acids detected in the acidic fraction, the majorone was citric acid which was present in a much greater amountin the conditioned medium of TA-l cells than in that of SO-lcells. The toxic effect of Al was reduced by adding citric or malicacid instead of the conditioned medium, but not by succinicor fumaric acid. Chelating abilities of the organic acids wereevaluated by shifts in their titration curves, and were foundto be closely correlated with the detoxification effects. Thus,the Al tolerance of TA-l cells may in fact be due to the chelatingeffect of citric acid which is abundantly released into themedium by the Al-tolerant carrot cells. (Received July 9, 1984; Accepted November 22, 1984)  相似文献   
28.
Fetus-in-fetu: report of a case   总被引:1,自引:0,他引:1  
A 5 month-old female was brought to our clinic because of diarrhea and abdominal distension. A plain radiograph demonstrated a mass with a vertebral column in the right upper quadrant of the abdomen. At operation a mass was found to be retroperitoneal, well encapsulated, and connected to the abdominal aorta of the host by two small vessels; no other connections and adhesions were seen between the mass and the host. The ovaries, uterus, and other pelvic and abdominal viscera of the host were normal. The mass was diagnosed as a fetus-in-fetu. The fetus-in-fetu, encapsulated with an amniotic capsule, was covered with skin and had a top with long hair, two protuberances, an amniotic hernial sac, upper limbs with syndactylic fingers, a gluteal region, and lower limbs with polysyndactylic toes. A brain mass and a spinal cord were identified in the cranial cavity and the vertebral canal. Several spinal ganglia and a nerve plexus were found. A noselike structure, upper lip, maxillalike bone with teeth, tonguelike structure, intestines, ribs, bones of the extremities, and skeletal muscles were also identified. A cloacalike cyst was observed to have an opening in the external female genitalia. Microscopically, a small number of motor neurons were seen in the brain mass and the anterior horn of the spinal cord. In the spinal ganglia, ganglion cells were differentiated. The submucosal and myenteric plexuses were seen in the intestinal wall. Well-differentiated muscle fibers were often accompanied with myelinated nerve fibers. Hematopoiesis was observed in the cranial bone marrow. The presence of the sex chromatin was confirmed in the nuclei of motor neurons and polymorphonuclear leukocytes. Thus, the present fetus-in-fetu, which was connected to the abdominal aorta of the host by two vessels, was a monozygotic twin which developed within its own amniotic cavity.  相似文献   
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