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1.
M. Šrůtek 《Plant Ecology》1993,106(1):73-87
The effects of different management practices (mainly mowing, grazing, nutrient enrichment) on floodplain vegetation were compared between the Austrian and Czech part of the Lunice River floodplain using nitrophilous vegetation with Urtica dioica. The vegetation samples situated on crosswise transects (40 in total) were used for the analysis of vegetation. Correlations between the floodplain width on these transects and the proportions (expressed as percentage of the total floodplain width) of selected characteristics (Urtica dioica and Phalaris arundinacea stands and managed areas) were not statistically significant. Differences in the proportions of selected characteristics between the two parts of the floodplain were not significant either, except differences in the proportion of managed areas and species richness (higher species richness and proportion of managed areas are in the Austrian part of the floodplain). The different environmental variables were used in ordinations (DCA and CCA) of vegetation samples. In the DCA, four groups of samples were interpreted. In the CCA changes the moisture gradient was the most important one. The transect distance (from the first transect in Austria) and the soil moisture had the closest relationship to the species data.  相似文献   

2.
Summary Using disomic chromosome substitution lines based on the susceptible wheat cultivar Chinese Spring, loose smut resistance of wheat cultivars Hope and Thatcher was shown to be conferred in each case by a single dominant major gene carried on chromosome 7 A (Hope) or 7 B (Thatcher). Partial resistance was determined by genes on an additional eight Hope or seven Thatcher chromosomes, and similarities were evident between the partial resistance genotypes ofHope and Thatcher. Chinese Spring exhibited a mean infection value of approximately 50%, indicating a significant level of partial resistance, which was found to be due, in part, to genes on the homoeologous chromosome arms 1 As, 1 Es and 1 Ds, and to cytoplasmic genes. Substitution of the Chinese Spring nucleus into the cytoplasm of Aegilops squarrosa, Ae. variabilis or Ae. mutica resulted in increased susceptibility to Ustilago tritici. Several alloplasmic lines of the resistant wheat cultivars Selkirk and Chris exhibited race-specific susceptibility to U. tritici.  相似文献   

3.
Summary A ligninase gene has been cloned from a Phanerochaete chrysosporium genomic DNA library. Nucleotide sequencing of the gene has revealed that the ligninase structural gene contains 1116 bp of the protein-encoding sequence, of which 84 bp encode the signal peptide. The protein-encoding sequence is interrupted by eight introns which conform to the universal G-T/A-G splicing rule observed for the 3 and 5 intron boundaries. The putative eukaryotic regulatory sequences, i.e. CAAT and TATA box-like sequences, are present in the 5 flanking region.  相似文献   

4.
Doubled haploid (DH) progeny from a cross between the scald susceptible barley (Hordeum vulgare L.) cultivar Ingrid and the resistant accession CI 11549 (Nigrinudum) was evaluated for resistance in the pathogen Rhynchosporium secalis (Oudem) J.J. Davis. Two linked and incompletely dominant loci confer resistance CI 11549 against isolate 4004. One is an allele at the complex Rrs1 locus on chromosome 3H close to the centromere; the other is located 22 cM distally on the long arm. The latter locus is designated Rrs4. In BC3-lines into Ingrid from CI 2222 (another Nigrinudum) resistance seems governed by one locus close to the telomeric region of chromosome 7H, probably allelic to Rrs2. In neither case did we find any trace of the recessive gene rh8 reported to be present in Nigrinudum. Various resistance donors of Ethiopian origin designated as Nigrinudum, Jet or Abyssinian were identical to a great extent with respect to markers, but differed in resistance to different isolates of scald or in barley yellow dwarf virus (BYDV) resistance. The implications for their use as differentials in scald tests and screening of germplasm collections are discussed.  相似文献   

5.
Koval'  O. M.  Voitenko  L. P.  Skok  M. V. 《Neurophysiology》2003,35(2):90-97
Using immunoperoxidase labeling, we studied the subunit composition of nicotinic acetylcholine receptors, nAChR, in preparations of the inferior mesenteric ganglion, IMG, of the guinea pig. Antibodies against synthetic peptides corresponding to agonist-binding membrane components of the 3, 4, 5, and 7 nAChR subunits were used. The presence of 3-specific antibodies was revealed on the membranes of about 58% of large neurons and of all small ganglionic cells (means of the greater and smaller diameters of the somata 53.8 ± 1.8 vs 33.6 ± 1.4 m, n = 20, and 14.1 ± 0.5 vs 7.5 ± 0.4 m, n = 50, respectively). Labeled cells of the rostral node were distributed evenly, while those of the caudal node were localized mostly within the regions of branching of the lumbar, colonic, and both hypogastric tracts. Immune labels to the 4 subunit were observed only on the membranes of small ganglionic cells distributed mostly in the region of the internodal commissural tracts. 5-Specific labeling was found on the membranes of about 63% large neurons, whose distribution was similar to that of the 3-labeled units, and on all small cells. Immunoreactivity to the 7 subunit was observed only on the membranes of small cells concentrated around unlabeled large neurons in the region of branching of the intermesenteric, colonic, and both hypogastric tracts. Thus, nAChR in the guinea pig IMG include 3, 4, 5, and 7 subunits. The nAChR with 3 and 5 subunits are localized on the membranes of large ganglionic neurons, whose number and topographical distribution are very close to each other. Our data agree with our results of earlier electrophysiological experiments and are indicative of the crucial role of the 3- and 5-containing nAChR in synaptic transmission via the ganglion under study. The presence of the 4- and 7-containing nAChR was found only on small ganglionic cells (which are, probably, not the relay units) and their processes.  相似文献   

6.
Relative quantum responsivity curves for inhibition of hypocotyl elongation in Sinapis alba L. seedlings previously grown in white light confirm that a marked end of day inhibition response can be induced by a monochromatic light treatment (30 min) at the end of the light period. In dark grown seedlings, however, no growth inhibition can be induced by a 30 min monochromatic light treatment. A prerequisite for an induction response appears to be a pretreatment with continuous light. Far red light is most effective with blue and red light showing a lesser effectiveness. The light pretreatment also shows a marked fluence rate dependency with respect to its ability to allow an induction response to manifest itself. The pretreatment required shows all the characteristics of a classical HIR response. The appearance of the effect in plants treated with the herbicide SAN 9789 seems to exclude chlorophyll as being the photoreceptor.Abbreviations SAN 9789 4-chloro-5-(methylamino)-2-(, , -trifluoro-m-tolyl)-3(2H)-pyridazinone - RG9 light long wavelength far red light (Schott RG9 colour glass) - FR far red light - WL white light - BL blue light - RL red light - D darkness - Ptot total phytochrome - Pfr far red absorbing form of phytochrome - HSR high irradiance response  相似文献   

7.
Internal motions of d-ribose selectively 2H-labeled at the 2 position were measured using solid state 2H NMR experiments. A sample of d-ribose-2 -d was prepared in a hydrated, non-crystalline state to eliminate effects of crystal-packing. Between temperatures of –74 and –60°C the C2–H2 bond was observed to undergo two kinds of motions which were similar to those of C2–H2/H2 found previously in crystalline deoxythymidine (Hiyama et al. (1989) J. Am. Chem. Soc., 111, 8609–8613): (1) Nanosecond motion of small angular displacement with an apparent activation energy of 3.6 ± 0.7 kcal mol–1, and (2) millisecond to microsecond motion of large amplitude with an apparent activation energy 4 kcal mol–1. At –74°C, the slow, large-amplitude motion was best characterized as a two-site jump with a correlation time on the millisecond time scale, whereas at –60°C it was diffusive on the microsecond time scale. The slow, large-amplitude motions of the C2–H2 bond are most likely from interconversions between C2-endo and C3-endo by way of the O4-endo conformation, whereas the fast, small-amplitude motions are probably librations of the C2–H2 bond within the C2-endo and C3-endo potential energy minima.  相似文献   

8.
J. L. Karihaloo 《Genetica》1987,73(3):217-221
Three cultivated varieties of Narcissus tazetta, Grand Soleil d'Or, Chinese Sacred Lily and Cypri, are triploid (2n = 3x+30) with the basic number 10. Grand Soleil d'Or has three homomorphic sets, each comprising 2 long submetacentrics, 4 long acrocentrics and 4 short acrocentrics. Karyotypes of the other two varieties are heteromorphic. Both possess one telocentric satellited chromosome. In addition, Cypri shows translocation between two chromosomes belonging to the seventh and eighth triplets. The number of secondary constrictions varies between 3 (Chinese Sacred Lily) and 4 (Grand Soleil d'Or and Cypri) which is also the number of nucleoli observed in the respective varieties.  相似文献   

9.
Intact, flowering, rose plants have been regenerated in vitro from excised embryos of crosses between Bridal Pink (the maternal parent) and several pollen parents. Explanted embryonic tissues developed into an organogenic callus which formed adventitious shoots after several months only on a modified half-strength Murashige & Skoog medium containing 1.0 M BA and 0.05 M NAA. These shoots could be separated, grown individually, rooted in a medium with no BA or NAA, with 1.0 M IBA, and transplanted to greenhouse media. Embryos ranging in age from 21 to 35 days post-pollination formed organogenic callus that eventually regenerated adventitious shoots. Histological examination of normally-developing embryos showed that well-defined embryonic axes were beginning to develop at approximately 20–25 days postpollination. Analysis of populations of regenerated plants from different crosses showed differences in flower color, growth habit, peduncle length, and petal number. This system may be useful for irradiation-mutation breeding and/or for the development of transgenic rose plants using Agrobacterium tumefaciens.Abbreviations BA 6-benzyladenine - IAA 3-indoleacetic acid - IBA 3-indolebutanoic acid - MS Murashige & Skoog - NAA -naphthaleneacetic acid - 2iP N6-(2-isopentenyl)adenosine  相似文献   

10.
To test the hypothesis that the T-cell receptor (Tcr) gene encodes a natural killer (NK) cell receptor molecule, three human NK clones and fresh peripheral blood lymphocytes with NK activity from two patients with a CD16+ lymphocytosis were analyzed for rearrangements and expression of the human Tcr , , and genes. Two of the clones displayed distinct rearrangements of their Tcr and genes and expressed mature Tcr , , and l RNA. However, one of the clones and both patient samples displayed marked NK activity but failed to rearrange or express any of their Tcr genes. These findings demonstrate that human natural killer activity is not dependent on Tcr gene rearrangement and expression. In addition, they confirm previous findings concerning the lack of Tcr and gene expression in some natural killer cells. Thus, they suggest the existence of additional NK-specific recognition molecules.  相似文献   

11.
The six binary montmorillonite clay-catalyzed reactions of the5-phosphorimidazolides of adenosine, cytidine, guanosine anduridine were performed and the eight dimers from each reactionwere separated and analyzed by HPLC. A 16–51-fold higher yieldof the 5-purine-pyrimidine dimers over that of the5-pyrimidine-purines was observed. The total yield of the5-purine-pyrimidine dimers was in the 50–70% range while thatof the 5-pyrimidine-purine dimers was 1.3–7.0%. Less sequenceselectivity was observed in the homodimers formed.Regioselectivity for the formation of 3, 5-phosphodiesterbonds over that found in the absence of clay was observed. The5-purine-pyrimidine, 5-pyrimidine-pyrimidine and5-purine-purine dimers had 3, 5-links in about half of theirphosphodiester bonds. The percent phosphodiester links in the5-pyrimidine-pyrimidine dimers was 18%, a value close to thatobserved in the absence of the montmorillonite catalyst. Themontmorillonite-catalyzed reaction of all four activatednucleotides was performed and the 24 products were separated andanalyzed. The trends observed in the binary reactions wereconfirmed and the results also showed that the relativereactivity of the activated monomers was A>G>C>U in theratio 8.2: 4.8: 1.3: 1 respectively. No 5-pyrimidine-purineswith a 5-U and pG3pU, pC3pAand pC3pG weredetected. These studies suggest that a limited population ofRNAs would have formed in catalyzed prebiotic reactions.  相似文献   

12.
Mesophyll protoplasts were produced from clones of two cultivars of Medicago sativa, Rangelander and Regen S. Protoplasts from the Regen S clone generally gave rise to calli while those from the Rangelander clone would undergo direct embryogenesis. Effects of plant growth conditions, donor tissue pretreatment and protoplast culture conditions on mesophyll protoplast production and subsequent development patterns were investigated. The major factor determining whether or not mesophyll protoplasts would be produced from either of the clones was the pretreatment in water of shoots excised from the donor plants. Pretreatment in water containing growth regulators did not alter protoplast production or development in the Regen S clone. Pretreatment of the Rangelander clone shoots with abscisic acid or naphthaleneacetic acid was slightly beneficial to embryo production while pretreatment with benzylaminopurine was detrimental. Altered leaf morphology induced by growth condition changes did not affect mesophyll protoplast production or subsequent development patterns when shoots were pretreated in water. Culture of protoplasts in liquid droplets or solid agar medium increased low density protoplast survival and subsequent embryo production in the Rangelander clone.  相似文献   

13.
B. D. Whitaker 《Planta》1992,187(2):261-265
Chloroplasts from fruits and leaves of Capsicum annuum cv. Bell Tower were purified on sucrose gradients, and the lipids were separated by column and thin-layer chromatography. The glycerolipids mono- and digalactosyldiacylglycerol (MGDG, DGDG), sulfoquinovosyldiacylglycerol (SQDG), and phosphatidylglycerol (PG) were quantified, and the fatty-acid composition at the 1 and 2 positions of the glycerol moiety (sn-1 and sn-2) was determined after hydrolysis with position-specific lipases. In fruit chloroplasts, 3-trans hexadecenoate (trans-3-161) was absent and replaced by palmitate (160) at sn-2 of PG, and 7,10,13-hexadecatrienoate (163) at sn-2 of MGDG was greatly reduced and largely replaced by linoleate (182). The ratio of 182 to linolenate (183) was consistently greater in glycerolipids from fruit compared with leaf chloroplasts. The lower percentage of C-16 fatty acids at sn-2 indicated that prokaryotic molecular species were reduced by 15% in DGDG, 40% in SQDG, and 90% in MGDG, in fruit compared with leaf chloroplasts. The MGDGDGDG ratios in fruit and leaf chloroplasts were 1.21 and 2.21, respectively. Taken together, the data indicate that chloroplasts in Capsicum fruit are deficient in three desaturases: those that convert 1) 160 to 3-trans-161 at sn-2 of PG, 2) 160 to 7cis-161 at sn-2 of MGDG, and 3) 182 to 183 at both sn-1 and sn-2 of various chloroplast glycerolipids.Abbreviations Chl chlorophyll - DGDG digalactosyldiacylglycerol - FS free sterol - GL galactolipid - MGDG monogalactosyldiacylglycerol - PE phosphatidyl ethanolamine - PG phosphatidylglycerol - PL phospholipid - SQDG sulfoquinovosyldiacylglycerol We are grateful to Dr. Roger Calza for providing us with the tobacco gt11 cDNA expression library and to Dr. Eric Huttner for his advice throughout the screening procedure. We also wish to thank M. Gosse for his assistance in growing and maintaining our plants. T.W.B. was supported by a BAP research grant from the Commission of the European Communities.  相似文献   

14.
Summary Three different conformations of proline rings in a protein in solution, Up, Down and Twist, have been distinguished, and stereospecific assignments of the pyrrolidine -, - and -hydrogens have been made on the basis of 1H-1H vicinal coupling constant patterns and intraresidue NOEs. For all three conformations, interhydrogen distances in the pairs -3, 3-3, 2-2, 2-2, and 3-3 (2.3 Å) are shorter than those in the pairs -2, 2-3, 3-2, 2-3, and 3-2 (2.7–3.0 Å), resulting in stronger NOESY cross peaks. For the Up conformation, the 3-2 and 2-3 spin-spin coupling constants are small (<3 Hz), and weak cross peaks are obtained in a short-mixing-time (10 ms) TOCSY spectrum; all other vicinal coupling constants are in the range 5–12 Hz, and result in medium to strong TOCSY cross peaks. For the Down form, the -2, 2-3, and 3-2 vicinal coupling constants are small, leading to weak TOCSY cross peaks; all other couplings again are in the range 5–12 Hz, and result in medium to strong TOCSY cross peaks. In the case of a Twist conformation, dynamically averaged coupling constants are anticipated. The procedure has been applied to bovine pancreatic trypsin inhibitor and Cucurbita maxima trypsin inhibitor-V, and ring conformations of all prolines in the two proteins have been determined.  相似文献   

15.
Summary Progenies of plants regenerated from scutellar callus of bread wheat (Triticum aestivum L.) were analysed for the organization of the intergenic spacer of the rRNA genes, located at the sites of the nucleolar organizer region (Nor loci). Sexual progenies derived from the regenerated plants of three wheat cultivars were subjected to this analysis. The respective DNAs were digested with the restriction endonuclease TaqI, and probed with a specific rDNA fragment by Southern blothybridization. The intergenic rDNA spacer could thus be characterized for each of the three cultivars. Thirty-eight progeny plants of the cultivars Chinese Spring and Miriam were found to be stable in their organisation of the Nor loci: no changes relative to the Nor of control plants from these cultivars were revealed. On the other hand, three progeny plants of ND7532 showed reduction in the number of the rDNA spacers. Since no variability in the Nor loci could be revealed among control ND7532 plants, this seems to indicate that the changes in the progeny of regenerated plants resulted from the in vitro culture of the scutellar callus. Grain glutenin and gliadin profiles of sexual progenyplants derived from scutellar calli of Chinese Spring, of Miriam as well as of ND7532 were identical to the respective control plants of these cultivars, indicating low (or no) somaclonal variation in these grain proteins in the analyzed plants.  相似文献   

16.
Résumé Nous avons fait élever des larves d'Anergates atratulus par des ouvrières deMyrmica laevinodis à 22°C. Pour y parvenir, il n'est pas utile de faire hivernerensemble les larves d'Anergates et les ouvrières deMyrmica. La présence de larves autochtones n'empêche pas lesMyrmica d'élever des larves d'Anergates. Dans toutes les expériences lesMyrmica ont été soumises au fridavant de recevoir des larves d'Anergates. Aucune reine deMyrmica n'a été utilisée dans ces expériences.Sur les 64 larves d'Anergates que nous avons utilisées, 38 se sont transformées en imagos. C'est au début de l'adoption et au moment des métamorphoses que périrent la plupart des 26Anergates perdus. Les femelles vécurent en général 2 ou 3 jours et cherchèrent très tôt à quitter le nid natal. Les mâles vécurent 2 à 3 semaines.
Summary Larvae ofAnergates atratulus were experimentally reared by workers ofMyrmica laevinodis, at 22°C. An overwintering of both larvae ofAnergates and workers ofMyrmica is not necessary for the success of that experiment. The presence of larvae ofMyrmica does not keep theMyrmica from rearing larvae ofAnergates. The workers ofMyrmica have been cooled, in all the experiments, before receiving larvae ofAnergates. No queen ofMyrmica have been used in that experiments.38 of the 64 larvae ofAnergates used became imagos. Most of the 26 lostAnergates died at the beginning of the adoption and during the metamorphosis. The females lived generally 2 or 3 days and tried, very early, to leave their native nest. The males lived 2 or 3 weeks.

Anergates atratulus Myrmica laevinodis, 22 . bmecme Anergates Myrmica. Myrmica Anergates. Myrmica Anergates. Myrmica . 64 Anergates , 38 . 26 Anergates 2 3 . 2 3 .
  相似文献   

17.
In the homothallic P/d sex interconversion system in a strain of a fission yeast (Schizosaccharomyces pombe), Pd is apparently twice as frequent as dP. This is interpreted to mean that Pd occurs before DNA replication, whereas dP occurs after. But the probabilities of their occurrence within a cell cycle are about the same (1 in 27 cell divisions).  相似文献   

18.
Summary Allozyme variation was examined in 22 populations of Pinus densiflora (Sieb, et Zucc.) and four geographic varieties of P. sylvestris (L.): var lapponica (Fries, Hartman), var armena (Komarov), var mongolica (Litvinov) and var sylvestriformis (Takenouchi). In addition, we developed paternal chloroplast (cp) DNA markers that distinguish P. densiflora from var lapponica, var armena and var mongolica. UPGMA cluster analysis based on Nei's distances between all pairwise combinations of the 22 populations revealed patterns corresponding strictly to geographic origin and taxonomic status. Analysis of allozyme variation in var lapponica, var armena and var mongolica demonstrated a high level of intrapopulational variability but a low level of interpopulational differentiation. It appears that the late Pleistocene blending of genetically diverse populations was responsible for the observed variation patterns. The constructed phylogenetic trees also showed late divergence of these three varieties. The var sylvestri formis was genetically distinct from the other three P. sylvestris varieties. The genetic distances separating var sylvestriformis from P. densiflora and the other taxa lend support to a separate taxonomic status for var sylvestriformis and a close relation with P. densiflora. We found that var sylvestriformis harbors admixtures of allozymes and cpDNA from both P. sylvestris and P. densiflora, which suggests an introgressive nature of this variety. Levels of intrapopulational variability were similar in P. sylvestris and P. densiflora, but interpopulational differentiation was much higher in P. densiflora. In the constructed phylogenetic trees, populations of this species were characterized by relatively long internode distances and branch lengths. The present results suggest that P. densiflora has a more advanced evolutionary age than P. sylvestris.  相似文献   

19.
Cellulose synthase genes (CesAs) encode a broad range of processive glycosyltransferases that synthesize (14)-D-glycosyl units. The proteins predicted to be encoded by these genes contain up to eight membrane-spanning domains and four `U-motifs' with conserved aspartate residues and a QxxRW motif that are essential for substrate binding and catalysis. In higher plants, the domain structure includes two plant-specific regions, one that is relatively conserved and a second, so-called `hypervariable region' (HVR). Analysis of the phylogenetic relationships among members of the CesA multi-gene families from two grass species,Oryza sativa and Zea mays, with Arabidopsis thaliana and other dicotyledonous species reveals that the CesA genes cluster into several distinct sub-classes. Whereas some sub-classes are populated by CesAs from all species, two sub-classes are populated solely by CesAs from grass species. The sub-class identity is primarily defined by the HVR, and the sequence in this region does not vary substantially among members of the same sub-class. Hence, we suggest that the region is more aptly termed a `class-specific region' (CSR). Several motifs containing cysteine, basic, acidic and aromatic residues indicate that the CSR may function in substrate binding specificity and catalysis. Similar motifs are conserved in bacterial cellulose synthases, the Dictyostelium discoideum cellulose synthase, and other processive glycosyltransferases involved in the synthesis of non-cellulosic polymers with (14)-linked backbones, including chitin, heparan, and hyaluronan. These analyses re-open the question whether all the CesA genes encode cellulose synthases or whether some of the sub-class members may encode other non-cellulosic (14)-glycan synthases in plants. For example, the mixed-linkage (13)(14)-D-glucan synthase is found specifically in grasses and possesses many features more similar to those of cellulose synthase than to those of other -linked cross-linking glycans. In this respect, the enzymatic properties of the mixed-linkage -glucan synthases not only provide special insight into the mechanisms of (14)-glycan synthesis but may also uncover the genes that encode the synthases themselves.  相似文献   

20.
Summary Effects of -galactosidase (from green coffee beans) digestion on lectin staining were examined in formalin-fixed, paraffin-embedded human pancreatic tissues from individuals of blood-group B and AB. Digestion with the enzyme resulted in almost complete loss of Griffonia simplicifolia agglutinin I-B4(GSAI-B4) staining in the acinar cells with concomitant appearance of Ulex europaeus agglutinin-I(UEA-I) staining in the corresponding cells. In addition, reactivity with soybean agglutinin(SBA) was also imparted by the enzyme digestion in GSAI-B4 positive acinar cells. -Galactosidase digestion following -galactosidase digestion neither reduced the reactivity with SBA nor induced the reactivity with Griffonia simplicifolia agglutinin-II(GSA-II) in GSAI-B4 positive cells, while in UEA-I positive cells, both reduction of SBA reactivity and appearance of GSA-II reactivity occurred after simple -galactosidase digestion as well as sequential digestion with - and -galactosidase. However, when -l-fucosidase digestion procedure was inserted between - and -galactosidase digestion, UEA-I staining imparted by -galactosidase digestion was markedly decreased in intensity and GSA-II reactivity was appeared in GSAI-B4 positive acinar cells. Furthermore, after sequential digestion with -galactosidase and fucosidase, reactivity with peanut agglutinin(PNA) was revealed in GSAI-B4 positive acinar cells as well as UEA-I positive cells in secretors. In non-secretors, strong PNA staining was usually observed in the acinar cells throughout the glands without enzyme digestion. These results confirmed that the -galactosidase induced GSA-II reactivity and the fucosidase induced PNA reactivity are due to precursors of different kinds of blood-group determinants and suggest that at least two kinds of B antigen determinants, i.e. Gal(1-3)[Fuc(1-2)]Gal(1-3,4)GlcNac and Gal(1-3)-[Fuc(1-2)]Gal(1-3)GalNAc are produced in GSAI-B4 positive acinar cells. The synthesis of the latter type of B antigen is assumed to be controlled under the secretory gene in human pancreas.Abbreviation GalNAc N-acetyl-d-galactosamine - Gal d-galactose - GlcNAc N-acetyl-d-glucosamine - Fuc l-fucose - NeuNAc N-acetylneuraminic acid (sialic acid)  相似文献   

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