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21.
A 3-year-old boy with partial No. 9 tetrasomy is described. The patient showed markedly retarded physical and mental development as well as multiple congenital anomalies. Routine chromosome analysis revealed an extra C-group chromosome. It had a pronounced secondary constriction at the proximal part of its long arm. Based on studies by a variety of banding techniques, the extra chromosome was identified to be an iso-dicentric No. 9 chromosome with inactivation of one of the two centromeres, the karyotype being 47,XY, + DIC (9)(Q2101). The value of BrdUrd treatment was emphasized in the detection of a very small piece of euchromatin within a long stretch of constitutive heterochromatin.  相似文献   
22.
A metabolite of 25-hydroxycholecalciferol has been isolated in pure form from chicken kidney homogenates. It has been identified as 25-hydroxy-24-oxocholecalciferol by means of ultraviolet absorption spectrophotometry, mass spectrometry, infrared spectrometry, nuclear magnetic resonance spectrometry, and specific chemical reactions.  相似文献   
23.
Early effects of various prostaglandins on the production of hexosamine-containing substances by cultured fibroblasts, which were derived from a rat carrageenin granuloma, were studied. At the stationary phase, the cells were exposed for 6 h to one of the prostaglandin A1 (PGA1), A2, B1, B2, D2, F, F, E1, E2 or arachidonic acid in various concentrations ranging from 0.01 to 10 μg/ml for all the stimuli and from 10 pg to 10 μg/ml for PGF. The activity of the cells in incorporating 3H-glucosamine into hexosamine-containing substances (acidic) glycosaminoglycans and glycoproteins) during this period was compared with that of control cells. All the stimuli tested showed more or less stimulative effect on the synthesis of hexosamine-containing substances at their specific concentrations. PGF was found to be the most potent stimulant and its stimulative effect was found significant even at the low concentration of 100 pg/ml. PGD2, F and E2 were the next potent stimuli. Their optimum dose were around 1 μg/ml but they still had significant stimulation at the concentration of 0.01 μg/ml. Effect of PGE2 was rather mild. Stimulation by PGA1, A2, B1 and B2 or arachidonic acid was seen at high dose, and its seemed to be non-specific. The results suggested that these prostaglandins such as PGF, D2, F and E2 play some important role on regulating the production of intercellular ground substances.  相似文献   
24.
The effect of PGF2α on the synthesis of hexosamine-containing substances (acidic glycosaminoglycans and glycoproteins) was studied in cultured fibroblasts derived from a rat carrageenin granuloma. Treatment with PGF2α ranging from 0.01 μg/ml to 20 μg/ml resulted in a significant increase of the production of these macromolecules by the cells. The stimulatory effect was found significant even at the low concentration of 10 ng/ml, and could be seen as early as 3h after exposure to PGF2α. The hexosamine-containing substances increased by PGF2α revealed that 80% of the increase was due to acidic glycosaminoglycans and the rest was due to glycoproteins.  相似文献   
25.
The active site of Bacillus macerans cyclodextrin glucanotransferase (CGTase) was examined by use of derivatives of phenyl alpha-maltopentaoside and phenyl alpha-glucoside as the substrates and acceptors, respectively. The active site of this enzyme is considered to be composed of tandem subsites (S4, S3, S2, S1, S1', S2', etc.) geometrically complementary to several glucose residues, and the alpha-1,4-glycosidic linkage of a substrate is split between S1 and S1'. The features of subsites S3 and S4 of the glycon binding site were estimated from the modes of the enzymatic action on phenyl alpha-maltopentaoside (G-G-G-G-G-phi; G, glucose residue; phi, phenyl residue; -, alpha-1,4-glycosidic bond) and its derivatives in which the CH2OH groups of the non-reducing-end glucose residues were converted to CH2I (IG-G-G-G-G-phi; IG, 6-deoxy-6-iodo-D-glucose residue), CH2NH2 (AG-G-G-G-G-phi; AG, 6-amino-6-deoxy-D-glucose residue), or COOH (CG-G-G-G-G-phi; CG, glucuronic acid residue). p-Nitrophenyl alpha-glucopyranoside (G-P; P, p-nitrophenyl residue) was used as an acceptor. HPLC analysis of the digests revealed that the CG residue of CG-G-G-G-G-phi was excluded from subsite S3, while it was accommodated in subsite S4. The Km and Vmax values for CG-G-G-G-G-phi were remarkably larger and smaller, respectively, than those for any other substrates.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
26.
A phosphonoglycosphingolipid, named F-21, was found in the nervous system of Aplysia kurodai by two-dimensional thin-layer chromatography (Abe, S., Araki, S., and Satake, M. (1986) Biomed. Res. (Tokyo) 7, 47-51). F-21 was isolated from the nervous tissue of Aplysia in this study, and its chemical structure was characterized as follows, where 2-AEP is 2-aminoethylphosphonate. (Formula; see text) The major aliphatic components of the ceramide portion were palmitic acid (75%), stearic acid (22%), octadeca-4-sphingenine (43%), and anteisononadeca-4-sphingenine (54%). Some information on the steric interactions in the sugar moiety was obtained by NMR spectroscopy. The ring protons of the internal galactose, H1, H3, and H4 and the H3 of the side chain galactose were shifted, as compared to the corresponding protons of dephosphonylated F-21. This may indicate the interactions between the 2-AEP residue of N-acetylgalactosamine and the internal galactose and between the N-acetyl group of N-acetylgalactosamine and the side chain galactose, implying a sterically restricted and unique structure that may relate to some biological functions of F-21.  相似文献   
27.
An antiserum against gibberellin A4 (GA4) raised in rabbits and its partially purified antibodies were used to develop radioimmunoassay (RIA) and indirect enzyme-linked immunosorbent assays (ELISAs) for GA4. Of three immunoassays tested, an ELISA based on the NAD-dependent redox cycle (enzyme-amplified ELISA) had highest sensitivity. Levels of methylated GA4 detected by this most sensitive method ranged from 0.1 fmol/assay (3.5 fg/assay) to 0.1 pmol/assay (3.5 pg/assay) suggesting applicability of this method to the detection of gibberellins in purified plant extracts.  相似文献   
28.
A novel type IV collagen-degrading metalloproteinase was purified from the conditioned media of a murine metastatic sarcoma cell line. The molecular weight of the purified enzyme was determined to be 100 kDa by SDS-PAGE, while 700 kDa by gel filtration suggesting that the enzyme has a multimer structure. This enzyme degrades type IV collagen, but neither type I collagen nor casein. The failure of trypsin treatment to enhance the enzyme activity suggested that the purified enzyme did not require activation. Although the enzyme seems to be classified as a matrix metalloproteinase, it was inhibited by neither tissue inhibitor of metalloproteinases (TIMP) nor TIMP-2 and thus represents a novel type IV collagen-degrading metalloproteinase.  相似文献   
29.
Adult T-cell leukemia (ATL)-related cells have the ability to produce a newly-isolated calcium-regulating protein, parathyroid hormone-related protein (PTHrP). The present study revealed that lectin-stimulated normal lymphocytes produce immunoreactive (IR)-PTHrP. When the T-cell-enriched fraction was purified from normal lymphocytes and then treated with lectin, a similar amount of IR-PTHrP was detected, suggesting that IR-PTHrP is an actual product of T-lymphocytes. A biologically active fragment of PTHrP, PTHrP(1-34), suppressed DNA synthesis in lectin-stimulated lymphocytes at concentrations greater than 50 pg/mL; the same concentration range of IR-PTHrP detected in the cultured media of lectin-stimulated lymphocytes. Therefore, it is reasonable to postulate that PTHrP is a cytokine inhibiting the cellular growth of normal lymphocytes.  相似文献   
30.
Peyer's patches in normal adult mice, neonatally thymectomized mice and mice injected with hydrocortisone were studied qualitatively and quantitatively by light microscopy. The patch was divided into germinal center, follicular area, parafollicular area and dome area. In normal mice, the volumetric ratio of the germinal center to the entire patch was 30.9%; that of the follicular area, 33.3%; that of the parafollicular area, 27.7%; and that of the dome area, 8.2%. Thymus-dependent small lymphocytes were 40% of small lymphocytes in the patch. Out of the total thymus-dependent small lymphocytes in the patch, 13% were included in the germinal center; 19%, in the follicular area; 62%, in the parafollicular area; and 6%, in the dome area. Hydrocortisone-sensitive small lymphocytes were 65% of the total small lymphocytes in the patch, the germinal center contained 9%; the follicular area, 84%; the parafollicular area, 2%; and the dome area, 5%. The epithelium over the dome area was invaded by numerous small lymphocytes. Forty-eight percent of lymphocytes within the epithelium over the dome were thymus-dependent and 67% were hydrocortisone-sensitive. It is concluded that Peyer's patch may be considered as a peripheral lymphatic tissue, functionally as well as morphologically.  相似文献   
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