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1.
Summary Amplification of the -globin gene by the polymerase chain reaction (PCR) and direct sequencing were used for a fast and reliable identification of the -globin variant Hb D Los Angeles and revealed the predicted GC substitution in codon 121. The same method showed the molecular defect in Hb Presbyterian to be a CG substitution in codon 108; this eliminates a MaeII restriction site.  相似文献   

2.
Summary Anonymous DNA probes mapping to human chromosome 16 and the distal region of the human X chromosome were isolated from a genomic library constructed using lambda EMBL3 and DNA from a mouse/human hybrid. The hybrid cell contained a der(16)t(X;16)(q26;q24) as the only human chromosome. Fifty clones were isolated using total human DNA as a hybridisation probe. Forty six clones contained single copy DNA in addition to the repetitive DNA. Pre-reassociation with sonicated human DNA was used to map these clones by a combination of Southern blot analysis of a hybrid cell panel containing fragments of chromosomes 16 and X and in situ hybridisation. One clone mapped to 16pter 16p13.11, one clone to 16p13.316p13.11, four clones to 16p13.316p13.13, two clones to 16p13.1316p13.11, one clone to 16p13.11, seven clones to 16p13.1116q12 or 16q13, four clones to 16q12 or 16q13, three clones to 16q1316q22.1, four clones to 16q22.10516q24, and nineteen clones to Xq26Xqter. Two clones mapping to 16p13 detected RFLPs. VK5 (D16S94) detected an MspI RFLP, PIC 0.37. VK20 (D16S96) detected a TaqI RFLP, PIC 0.37 and two MspI RFLPs, PIC 0.30 and 0.50. The adult polycystic kidney disease locus (PKD1) has also been assigned to 16p13. The RFLPs described will be of use for genetic counselling and in the isolation of the PKD1 gene. Similarly, the X clones may be used to isolate RFLPs for genetic counselling and the isolation of genes for the many diseases that map to Xq26qter.  相似文献   

3.
A novel syrup containing neofructo-oligosaccharides was produced from sucrose (Brix 70) by whole cells of Penicillium citrinum. The efficiency of fructo-oligosaccharides production was more than 55% and those of the main carbohydrate components, 1-kestose (Fruf 21Fruf 21 Glc), nystose (Fruf 21Fruf 21 Fruf 21 Glc) and neokestose (Fruf 26 Glc12 Fruf), were 22, 14 and 11%, respectively.  相似文献   

4.
Negative-ion fast atom bombardment tandem mass spectrometry has been used in the characterization of non-, mono-, di- and trisulfated disaccharides from heparin and heparan sulfate. The positional isomers of the sulfate group of monosulfated disaccharides were distinguished from each other by negative-ion fast atom bombardment tandem mass spectra, which provide an easy way of identifying the positional isomers. This fast atom bombardment collision induced dissociation mass spectrometry/mass spectrometry technique was also applied successfully to the characterization of di- and trisulfated disaccharides.Abbreviations FABMS fast atom bombardment mass spectrometry - CID collision induced dissociation - MIKE mass analysed ion kinetic energy - MS/MS mass spectrometry/mass spectrometry - HPLC high performance liquid chromatography - UA d-gluco-4-enepyranosyluronic acid - CS chondroitin sulfate - DS dermatan sulfate - HA hyaluronan - Hep heparin - HS heparan sulfate - UA(14) GlcNAc 2-acetamido-2-deoxy-4-O-(-d-gluco-4-enepyranosyluronic acid)-d-glucose - UA(14)GlcNAc6S 2-acetamido-2-deoxy-4-O-(-d-gluco-4-enepyranosyluronic acid)-6-O-sulfo-d-glucose - UA2S(14)GlcNAc 2-acetamido-2-deoxy-4-O-(2-O-sulfo--d-gluco-4-enepyranosyluronic acid)-d-glucose - UA2S(14)GlcNAc6S 2-acetamido-2-deoxy-4-O-(2-O-sulfo--d-gluco-4-enepyranosyluronic acid)-6-O-sulfo-d-glucose - UA(14)GlcN6S 2-amino-2-deoxy-4-O-(-d-gluco-4-enepyranosyluronic acid)-6-O-sulfo-d-glucose - UA2S(14)GlcN 2-amino-2-deoxy-4-O-(2-O-sulfo--d-gluco-4-enepyranosyluronic acid)-d-glucose - UA2S(14)GlcN6S 2-amino-2-deoxy-4-O-(2-O-sulfo--d-gluco-4-enepyranosyluronic acid)-6-O-sulfo-d-glucose - UA(14)GlcNS 2-deoxy-2-sulfamino-4-O-(-d-gluco-4-enepyranosyluronic acid)-d-glucose - UA(14)GlcNS6S 2-deoxy-2-sulfamino-4-O-(-d-gluco-4-enepyranosyluronic acid)-6-O-sulfo-d-glucose - UA2S(14)GlcNS 2-deoxy-2-sulfamino-4-O-(2-O-sulfo--d-gluco-4-enepyranosyluronic acid)-d-glucose - UA2S(14)GlcNS6S 2-deoxy-2-sulfamino-4-O-(2-O-sulfo--d-gluco-4-enepyranosyluronic acid)-6-O-sulfo-d-glucose - UA(13)GalNAc 2-acetamido-2-deoxy-3-O-(-d-Gluco-4-enepyranosyluronic acid)-d-galatose - UA(13)GalNAc4S 2-acetamido-2-deoxy-3-O-(-d-gluco-4-enepyranosyluronic acid)-4-O-sulfo-d-galactose - UA(13)GalNAc6S 2-acetamido-2-deoxy-3-O-(-d-gluco-4-enepyranosyluronic acid)-6-O-sulfo-d-galactose - UA2S(13)GalNAc 2-acetamido-2-deoxy-3-O-(2-O-sulfo--d-gluco-4-enepyranosyluronic acid)-d-galactose - UA2S(13)GalNAc4S 2-acetamido-2-deoxy-3-O-(2-O-sulfo--d-gluco-4-enepyranosyluronic acid)-4-O-sulfo-d-galactose - UA2S(13)GalNAc6S 2-acetamido-2-deoxy-3-O-(2-O-sulfo--d-gluco-4-enepyranosyluronic acid)-6-O-sulfo-d-galactose - UA(13)GalNAcDiS 2-acetamido-2-deoxy-3-O-(-d-gluco-4-enepyranosyluronic acid)-4,6-di-O-sulfo-d-galactose - UA(13)GlcNAc 2-acetamido-2-deoxy-3-O-(-d-gluco-4-enepyranosyluronic acid)-d-glucose.  相似文献   

5.
4-O-Glycosylation of 2-azidoethyl 2,3,6-tri-O-benzyl-4-O-(2,3-di-O-benzyl-6-O-benzoyl--D-galactopyranosyl)--D-glucopyranoside with a disaccharide donor, 4-trichloroacetamidophenyl 4,6-di-O-acetyl-2-deoxy-3-O-(2,3,4,6-tetra-O-acetyl--D-galactopyranosyl)-1-thio-2-trichloroacetamido--D-galactopyranoside, in dichloromethane in the presence of N-iodosuccinimide and trifluoromethanesulfonic acid resulted in a tetrasaccharide, 2-azidoethyl (2,3,4,6-tetra-O-acetyl--D-galactopyranosyl)-(1 3)-(4,6-di-O-acetyl-2-deoxy-2-trichloroacetamido--D-galactopyranosyl)-(1 4)-(2,3-di-O-benzyl-6-O-benzoyl--D-galactopyranosyl)-(1 4)-2,3,6-tri-O-benzyl--D-glucopyranoside, in 69% yield. The complete removal of O-protecting groups in the tetrasaccharide, the replacement of N-trichloroacetyl by N-acetyl group, and the reduction of the aglycone azide group to amine led to the target aminoethyl glycoside of -D-Gal-(1 3)--D-GalNAc-(1 4)--D-Gal-(1 4)--D-Glc-OCH2CH2NH2 containing the oligosaccharide chain of asialo-GM1 ganglioside in 72% overall yield. Selective 3-O-glycosylation of 2-azidoethyl 2,3,6-tri-O-benzyl-4-O-(2,6-di-O-benzyl--D-galactopyranosyl)--D-glucopyranoside with thioglycoside methyl (ethyl 5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-2-thio-D-glycero--D-galacto-2-nonulopyranosyl)oate in acetonitrile in the presence of N-iodosuccinimide and trifluoromethanesulfonic acid afforded 2-azidoethyl [methyl (5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-D-glycero--D-galacto-2-nonulopyranosyl)oate]-(2 3)-(2,6-di-O-benzyl--D-galactopyranosyl)-(1 4)-2,3,6-tri-O-benzyl--D-glucopyranoside, the selectively protected derivative of the oligosaccharide chain of GM3 ganglioside, in 79% yield. Its 4-O-glycosylation with a disaccharide glycosyl donor, (4-trichloroacetophenyl-4,6-di-O-acetyl-2-deoxy-3-O-(2,3,4,6-tetra-O-acetyl--D-galactopyranosyl) 1-thio-2-trichloroacetamido--D-galactopyranoside in dichloromethane in the presence of N-iodosuccinimide and trifluoromethanesulfonic acid gave 2-azidoethyl (2,3,4,6-tetra-O-acetyl--D-galactopyranosyl)-(1 3)-(4,6-di-O-acetyl-2-deoxy-2-trichloroacetamido--D-galactopyranosyl)-(1 4)-{[methyl (5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-D-glycero--D-galacto-2-nonulopyranosyl)onate]-(2 3)}-(2,6-di-O-benzyl--D-galactopyranosyl)-(1 4)-2,3,6-tri-O-benzyl--D-glucopyranoside in 85% yield. The resulting pentasaccharide was O-deprotected, its N-trichloroacetyl group was replaced by N-acetyl group, and the aglycone azide group was reduced to afford in 85% overall yield aminoethyl glycoside of -D-Gal-(1 3)--D-GalNAc-(1 4)-[-D-Neu5Ac-(2 3)]--D-Gal-(1 4)--D-Glc-OCH2CH2NH2 containing the oligosaccharide chain of GM1 ganglioside.  相似文献   

6.
Summary A p-nitrophenyl--d-glucopyranosidase from Bacillus thermoamyloliquefaciens KP 1171 capable of growing at 30°–66°C was assigned to an oligo-1,6-glucosidase (dextrin 6--d-glucanohydrolase, EC 3.2.1.10). The enzyme was compared with its homologous counterparts from B. cereus NY-14, B. cereus ATCC 7064 (each mesophile), B. coagulans ATCC 7050 (facultative thermophile), B. thermoglucosidasius KP 1006 (DSM 2542, obligate thermophile) and B. flavocaldarius KP 1228 (extreme thermophile) in thermostability and kinetic parameters at suboptimal temperatures for isomaltosaccharides (2–6 glucose units). This analysis showed that the efficiency of each isomaltosaccharide hydrolysis changes in a convex manner with increasing thermostability on the transition, NY-14 ATCC 7064 ATCC 7050 KP 1071 KP 1006 KP 1228 enzymes, with a maximum at KP 1071 or ATCC 7050 enzyme.Presented at the Annual Meeting of the Agricultural Chemical Society of Japan, Kyoto, April 1, 1986  相似文献   

7.
The genes coding for the regulatory type I subunit (PRKAR1A) and the catalytic subunit (PRKACB) of cAMP-dependent protein kinase and the genes for interleukin 1 (IL1A) and interleukin 1 (IL1B) were localized in the pig by means of radioactive in situ hybridization. PRKAR1A was mapped to 12p1.4 and PRKARB to 6q3.1 q3.3. The genes for IL1A and IL1B were both assigned to Chromosome (Chr) 3, in the region q1.2 q1.3 and q1.1 q1.4, respectively. The cDNA nucleotide sequences of these porcine genes were compared with those of human, mouse, and cattle. The location of the genes was discussed in relation to the position of their homologous loci in these mammalian species.  相似文献   

8.
E. Schäfer  B. Marchal  D. Marmé 《Planta》1971,101(3):265-276
Summary The in vivo phototransformation kinetics of mustard hook and cotyledon phytochrome exhibit a deviation from a single first order curve, quite similar to that for pumpkin hooks as reported in a previous paper (Boisard, Marmé and Schäfer, 1971). The P frPrkinetics can be characterized by the ratios fr, I · P fr I / fr, II · P fr, II and where P fr I and P fr II are two populations of phytochrome molecules which convert to P rwith a first order half-life of and . These ratios depend on the length of time of etiolation. The ratio fr, I · P fr I / fr, II · P fr, II is independent of the amount of total P frpresent at the beginning of the P frPrphototransformation after a non-saturating dose of red light. The half-lives of the two populations, however, depend on the concentration of total P frinitially present. P frPrphototransformation kinetics with different light intensities show that reciprocity holds.  相似文献   

9.
The effect on cholesterol metabolism in Hep G2 hepatoma cells was studied for new analogues of 15-ketosterol [3-hydroxy-5-cholest-8(14)-en-15-one] (I): (24S)-3-hydroxy-24-methyl-5-cholesta-8(14),22-diene-15-one (II), (24S)-3-hydroxy-24-methyl-5-cholesta-8(14),22-diene-15-one (III), and (24S)-24-methyl-5-cholesta-8(14),22-diene-3,15-dione (IV). Analogues (I) and (II) were found to be equally effective inhibitors of cholesterol biosynthesis after a 3-h incubation with Hep G2 cells; however, (II) produced a stronger inhibitory effect after a 24-h incubation or after an incubation of cells preliminarily treated with the inhibitor in a medium containing no ketosterol. The ability of ketosterols to inhibit cholesterol biosynthesis decreased in the order (II) > (IV) > (III). Ketosterol (II) inhibited, whereas ketosterol (III) stimulated the biosynthesis of cholesteryl esters. (IV) stimulated the biosynthesis of cholesteryl esters at a concentration of 1–10 M and exerted no marked effect at a concentration of 30 M. These results indicate that 8(14)-15-ketosterols containing a modified side chain are of interest as regulators of cholesterol metabolism in liver cells.  相似文献   

10.
Wu AM 《Neurochemical research》2002,27(7-8):593-600
Glycosphingolipids (GSLs) contain many carbohydrate epitopes or crypto-glycotopes for Gal and GalNAc reactive lectins. Many of them are in the nervous system and function as important receptors in various life processes. During the past two decades, 11 mammalian structural units have been used to express the binding domain of applied lectins. They are: F, GalNAc1 3GalNAc; A, GalNAc1 3Gal; T, Gal1 3GalNAc; I, Gal1 3GlcNAc; II, Gal1 4GlcNAc; B, Gal1 3Gal; E, Gal1 4Gal; L, Gal1 4Glc; P, GalNAc1 3Gal; S, GalNAc1 4Gal, and Tn, GalNAc1 Ser(Thr). Although 10 of them occur in GSLs, only 3 (L , S , and T ) are found in human brain, and 2 (L and II ) are present in the inner structures of human blood group active GSLs. In the families of gangliosides, L and II represent 55% of the total structural units, while the other three units (T , P , and S ) constitute the rest. To facilitate the selection of lectins that could serve as structural probes, the carbohydrate binding specificities of Gal/GalNAc reactive lectins have been classified according to their highest affinity for the structural units and their binding properties expressed by decreasing order of reactivity. Hence, the binding relation between GSLs and Gal/GalNAc specific lectins can be established.  相似文献   

11.
Surovaya  A. N.  Grokhovsky  S. L.  Burckhardt  G.  Fritzsche  H.  Zimmer  Ch.  Gursky  G. V. 《Molecular Biology》2002,36(5):726-735
The interaction of short nucleotide duplexes with bis-netropsins, in which netropsin fragments are linked tail-to-tail via cis-diammineplatinum group (Nt–Pt(NH 3 )–Nt) or aliphatic pentamethylene chain (Nt–(CH 2 ) 5 –Nt), has been studied. Both bis-netropsins have been shown to bind to DNA oligomer 5"-CCTATATCC-3" (I) as a hairpin with parallel orientation of netropsin fragments in 1:1 stoichiometry. Monodentate binding has been detected upon binding of bis-netropsins to other duplexes of sequences 5"-CCXCC-3" [where X = TTATT (II), TTAT (III), TTTTT (IV), and AATTT (V)] along with the binding of bis-netropsins as a hairpin. The formation of dimeric antiparallel motif between the halves of two bound bis-netropsin molecules has been observed in the complexes of Nt–(CH 2 ) 5 –Nt with DNA oligomers IV and V. The ratio of binding constant of bis-netropsin as a hairpin ( 2) to monodentate binding constant ( 1) has been shown to correlate with the width and/or conformational lability of DNA in the binding site. The share of bis-netropsin bound as a hairpin decreases in the order: TATAT > TTATT > TTAAT > TTTTT > AATTT, whereas the contribution of monodentate binding rises. The minimal strong binding site for Nt–Pt(NH 3 )–Nt and Nt–(CH 2 ) 5 –Nt binding as a hairpin has been found to be DNA duplex 5"-CGTATACG-3".  相似文献   

12.
Photosynthetic water oxidation proceeds by a four-step sequence of one-electron oxidations which is formally described by the transitions S0 S1, S1 S2, S2 S3, S3 (S4) S0. State S1 is most stable in the dark. Oxygen is released during S3 (S4) S0. Hydroxylamine and hydrazine interact with S1. They cause a two-digit shift in the oxidation sequence as observed from the dark equilibrium, i.e. from S1 S2 : S2 S3 : S3 (S4) S0 : S0 S1 :... in the absence of the agents, to S1 * S0 : S0 S1 : S1 S2 : S2 S3 :... in the presence of hydroxylamine or hydrazine.We measured the concentration dependence of this two-digit shift via the pattern of proton release which is associated with water oxidation. At saturating concentrations hydroxylamine and hydrazine shift the proton-release pattern from OH+(S1 S2) : 1H+(S2 S3) : 2H(S3 S0) : 1H+(S0 S1) :... to 2H+(S1 * S0) : 1H+(S0 S1) : OH+(S1 S2) : 1H+(S2 S3) : 2H+(S3 S0) :... The 2H+ were released upon the first excitation with a half-rise time of 3.1 ms, both with hydroxylamine and withydrazine. The concentration dependence of the shift was rather steep with an apparent Hill coefficient at half saturation of 2.43 with hydroxylamien (Förster and Junge (1985) FEBS Lett. 186, 53–57) and 1.48 with hydrazine. The concentration dependence could be explained by cooperative binding of n3 molecules of hydroxylamine and of n2 molecules of hydrazine, respectively. Tentatively, we explain the interaction of hydroxylamine and hydrazine with the water-oxidizing complex (WOC) as follows: Two bridging ligands, possible Cl- or OH-, which normally connect two Mn nuclei, can be substituted by either 4 molecules of hydroxylamine or 2 molecules of hydrazine when the WOC resides in state S1.Abbreviations DNP-INT dinitrophenylether of iodonitrothymol - FWHM full width at half maximum - NR neutral red (3-amino-7-dimethylamino-2-methylphenazine-HCI) - PS II photosystem II - WOC or (in formulas:) W water-oxidizing complex Dedicated to Prof. L.N.M. Duysens on the occasion of his retirement.  相似文献   

13.
As part of the multicenter project entitled Pathobiological Determinants of Atherosclerosis in Youth (PDAY), we are testing polymorphisms in candidate genes of atherosclerosis and hypertension for associations with arterial lesions in autopsied young persons. In this study, we used temperature gradient gel electrophoresis (TGGE) to type the Met235Thr polymorphism in exon 2 of the angiotensinogen gene (AGT) that is associated with essential hypertension in some human populations. In addition to Met235Thr, we detected and sequenced four other TGGE variants in exon 2 of AGT. These included two new amino acid substitutions (Thr209 Ile and Leu211Arg) that were found only among black PDAY cases. The frequency of the Ile209 mutation was 0.002 and the frequency of the Arg211 was 0.006 in 260 black PDAY cases. The other two TGGE variants were Tyr248Cys and a TC substitution at nucleotide position 171 that had been identified in previous studies. We also developed restriction isotyping for rapid typing of each AGT variant using PCR amplification and digestion with diagnostic restriction enzymes.  相似文献   

14.
Summary DNA sequencing was used to determine the specific types of DNA base changes induced following in vivo exposure of Escherichia coli to the ethylating agent N-ethyl-N-nitro-N-nitrosoguanidine (ENNG) and the hydroxyethylating agent 1-(2-hydroxyethyl)-1-nitrosourea (HENU) using the xanthine guanine phosphoribosyltransferase (gpt) gene as the genetic target. We observed that 22/30 of the ENNG-induced mutations were GCAT transitions, 4/30 were ATGC transitions, 3/30 were ATTA transversions, and 1/30 was an ATCG transversion. We observed that 37/40 HENU-induced mutations were GCAT transitions and that the remaining 3/40 were ATGC transitions. A majority of the GCAT transitions induced by ENNG and HENU (68% and 73%, respectively) occurred at the second guanine of the sequence 5-GG(A or T)-3; this sequence specificity was similar to that previously seen with the alkylating agents N-methyl- and N-ethyl-N-nitrosourea (MNU and ENU) and N-methyl-N-nitro-N-nitrosoguanidine (MNNG). A DNA strand preference for the GA changes (antisense strand), previously noted for MNU, ENU, and MNNG, was observed following exposure to HENU and ENNG. The ATGC transitions induced by ENNG, HENU, and ENU also exhibit a sequence specificity with 13/13 mutations occurring at the T of the sequence 5-NTC-3. A strand preference was not apparent for these mutations.  相似文献   

15.
Summary Studies on the metabolism ofL-sorbose by cell-free extracts fromGluconobacter melanogenus IFO 3293 grown inL-sorbose — containing media confirm by different methodology the observations by Makover et al. that the sequence in this bacterium isL-sorbose L-sorbosone 2-keto-L-gulonic acid L-idonic acid.Dedicated to the memory of Prof. Dr. Konrad Bernhauer. For preceeding paper in this series see Kitamura & Perlman (1975).  相似文献   

16.
Choi JH  Park HS  Oh HB  Lee JH  Suh YJ  Park CS  Shin HD 《Human genetics》2004,114(4):337-344
A recent study has demonstrated the possible involvement of a leukotriene C4 synthase (LTC4S) gene polymorphism in ASA-intolerant asthma (AIA) in a Polish population, whereas no significant association was noted in other populations. To investigate the role of genetic polymorphism in AIA development, we screened single nucleotide polymorphisms (SNPs) of the key enzymes involved in arachidonate metabolism, and the cysteinyl leukotriene receptor 1 (CYSLTR1) in a large Korean population with AIA: 93 AIA and 181 ASA-tolerant asthma (ATA) patients, and 123 normal controls. The single-base extension method was used to genotype SNPs in 5-lipoxygenase (ALOX5, –1708GA, 21CT, 270GA, 1728GA), ALOX5-activating protein (ALOX5AP, 218AG), prostaglandin-endoperoxide synthase 2 (PTGS2, COX2, –162CG, 10TG, R228H, V511A), LTC4S (–444AC), and CYSLTR1 (927TC). Haplotype analyses were undertaken for the SNPs in ALOX5. No significant differences in allele and genotype frequencies of single SNPs were observed between the patient groups (P>0.05). However, the frequency of the ALOX5-ht1[G-C-G-A] haplotype in the AIA group was significantly higher than its frequency in the ATA group with a probability (P) of 0.01, odds ratio (OR) of 5.0, and 95% confidence interval (95%CI) of 1.54–17.9, and in the normal controls (P=0.03, OR=4.5, 95%CI=1.1–18.4), by using a dominant model. These results suggest a lack of association between the ALOX5AP, PTGS2, LTC4S, and CYSLTR1 gene polymorphisms and the AIA phenotype in the Korean population. However, the possible involvement of ALOX5-ht1[G-C-G-A] in AIA development is suggested.J.-H. Choi and H.-S. Park contributed equally to this work as first authors  相似文献   

17.
Summary A mentally retarded boy with trisomy 9p is described. This trisomy arose through aberrant segregation of translocation chromosome during meiosis in his mother, who has a complex translocation involving chromosomes 9, 13, and 14. Based on both G-, Q-banding, and DNA replication patterns, the patient's karyotype was identified as 47,XY,-13, +(9;13) (9pter9q12::13q3113qter), +t(13;14) (13pter13q31::14pl?14pter). We suppose his mother's karyotype to be 46,XX,-9,-13,-14,+t(9;13) (9pterq12::13q3113qter), +t(13;14) (13pter13q31::14pl?14pter), +t(9;14) (9qter9q12::14pl?14qter). His phenotypically normal brother and sister are also carriers, having the same translocation chromosome as their mother. Clinical findings of the patient included peculiar face with hypertelorism, prominent nasal bridge and deformed helix, marked delay of osseous development, hypoplastic phalangia in fingers and toes, dysplastic nails and absence of digital triradii.  相似文献   

18.
Summary Gene dosage studies yielded results consistent with assignment of the locus for nucleoside phosphorylase to band 14q13. The red blood cells from a patient with the karyotype 47,XX,+der(14),t(8;14)(8qter8q24: :14q2114pter)pat had enzyme activity 50% higher than red cells from 47 normal controls, two trisomies involving chromosomes other than 14, and five balanced translocations involving chromosome 14. On the other hand, the red cells of a case with a karyotype 45,XX,-14,-22,+der(22),t(14;22)(14qter14q11 or 14q12::22p1122qter)mat and a case with a karyotype 47,XX, +der(14),t(14;16)(14pter14q11::16q2416qter)mat had normal activity.  相似文献   

19.
Summary Phytochrome photoconversions PrPfr and PfrPr can be measured by differential spectrophotometry in dry seeds (6% water content) of Pinus nigra Arn. A red light irradiation given before imbibition induces germination when the seeds are subsequently wetted and kept in darkness.In continuous darkness the phytochrome content shows a drastic increase at the beginning of moistening.The detectable pigment is entirely in the Pr form. The normal PfrPr dark reversion is observed. Pfr destruction does not take place.  相似文献   

20.
For homogeneous hypercycles with 2, 3 or 4 substances the future behavior of its trajectories is easily understood, in fact any trajectory converges to an equilibrium point as t +. In this paper we study the descent of the trajectories, i.e. their behavior as t -. It turns out that this backward behavior is not as uniform as the forward behavior. In fact, depending on the initial points some -limit sets are singletons while others consist of certain edges of the state simplex.Work partially supported by Deutsche Forschungsgemeinschaft under grant number Au 66–1  相似文献   

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