共查询到20条相似文献,搜索用时 15 毫秒
1.
Jan B L Damm Hans Voshol Karl Hård Johannis P Kamerling Gijs W K Van Dedem Johannes F G Vliegenthart 《Glycoconjugate journal》1988,5(3):221-233
TheN-linked carbohydrate chains of the-subunit of highly purified urinary human chorionic gonadotropin have been re-investigated. The oligosaccharides were released enzymatically by peptide-N
4-(N-acetyl--glucosaminyl)asparagine amidase-F, and fractionated by a combination of FPLC and HPLC. As a result of the application of improved fractionation methods, apart from the earlier reported carbohydrate chains, also small amounts of trisialo tri- and tri-antennary oligosaccharides were found. The primary structures of the latter carbohydrate chains have been determined by 500-MHz1H-NMR spectroscopy to beAbbreviations hCG
human chorionic gonadotropin
- hCG-
-subunit
- hCG-
-subunit
- PNGase-F
peptide-N
4-(N-acetyl--glucosaminyl)asparagine amidase-F (E.C. 3.5.1.52)
- endo-F
endo--N-acetylglucosaminidase-F (E.C. 3.2.1.96)
- SDS
sodium dodecyl sulphate
- PAGE
polyacrylamide gel electrophoresis
- CBB
coomassie brilliant blue R 250
- GlcNAc
N-acetylglucosamine
- NeuAc
N-acetylneuraminic acid
- Man
mannose
- Gal
galactose
- Fuc
fucose 相似文献
2.
S. A. Clulow M. J. Wilkinson R. Waugh E. Baird M. J. DeMaine W. Powell 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1991,82(5):545-551
Summary Seventeen potato dihaploids, produced by pollinating the tetraploid (2n = 48) cv Pentland Crown with pollen from Solanum phureja (2n = 24) dihaploid inducer clones, were studied. Since dihaploids are thought to develop parthenogenetically from unfertilized ovules they were expected to be euploid (2n = 24), but somatic chromosome counts showed that 15 of the 17 dihaploids were aneusomatic. Ten of the clones were predominantly diploid (2n = 24) with a proportion of hyperploid cells that contained 25 or 26 chromosomes. Five of the dihaploids contained variable numbers of triploid cells (2n = 36). RFLP analysis was used to determine whether the additional chromosomes were from S. phureja or S. tuberosum. Unique hybridizing fragments present in S. phureja but not in Pentland Crown were identified. These S. phureja-specific restriction fragments were present in some of the dihaploid offspring of Pentland Crown. Of the 5 clones that contained triploid cells 4 had S. phureja type banding. Four of the 10 aneusomatic clones that contained hyperploid cells had the unique S. phureja hybridizing fragments. We propose that ovules of Pentland Crown were fertilized by pollen from S. phureja and that the aneusomatic clones were derived from triploid zygotes from which some of the S. phureja chromosomes were eliminated. We consider that this is an additional mechanism of dihaploid formation in potato. 相似文献
3.
Dr. Y. Savidan 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1980,58(2):153-156
Summary Cytological analyses in series of crosses between 7 sexual pistillate and 8 apomictic staminate parents of speciesPanicum maximum (Gramineae) are reported. Although these 15 progenitors were tetraploid (2n = 32), 2 dihaploids (2n = 16), 45 hexaploids (2n = 48) and 5 octoploids (2n = 64) were observed among 333 progeny plants. The role of unreduced gametes as the originators of polyploidy is discussed in relation to the so-called elements of apomixis. The 2 dihaploids appeared to be sexual while the hexaploids and octoploids were all apomictic. At the tetraploid level sexual and apomictic hybrids segregated in a ratio close to 11. These results were then compared to those already obtained from studies on other tropical grasses and indicate a simple genetic determinism for gametophytic apomixis. 相似文献
4.
C. J. Liu M. D. Gale 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1989,77(2):233-240
Summary Isoelectric focusing of extracts from the endosperm of mature grains of hexaploid wheat and related species was used to study the genetic control of Iodine binding factor (IBF). Ten IBF bands were present in Chinese Spring (CS) and analysis of the nullisomictetrasomic and ditelosomic lines of CS showed nine of them to be controlled by genes on the long arms of the homoeologous group 5 chromosomes. Five alleles were detected at Ibf-A1 locus, four at Ibf-B1 and four at Ibf-D1 among a sample of 46 wheat genotypes. Homoeoloci were found on chromosome 5R of Secale cereale, 5E of Agropyron elongatum, 5U of Aegilops umbellulata, 5Agi of Agropyron intermedium, 5S1 and 4S1 of Aegilops sharonensis and 4H of Hordeum vulgare. 相似文献
5.
K. Jones 《Plant Systematics and Evolution》1990,172(1-4):263-271
Meiotic pairing inTradescantia soconuscana 2n=26 (6M+16A+4T) suggests that it has a tetraploid constitution which is not apparent in its chromosome number. Its nombre fondamental of 32 indicates that it could have evolved from an ancestor with x=8 by a combination of Robertsonian fusion, hybridization and polyploidy. The 2n=16 (8A+8T) karyotype of a closely related diploid supports this. The allied genusZebrina may have followed a similar method of chromosome evolution. 相似文献
6.
I. O. Ahn Bui Van Le C. Gendy K. Tran Than Van 《Plant Cell, Tissue and Organ Culture》1996,45(3):237-243
Direct somatic embryos were differentiated on cotyledon transverse Thin Cell Layers (tTCLs) of Panax ginseng after 9 weeks in the Murashige and Skoog basal (MS) medium containing 2,4-d (5M). When MS medium containing 2,4-d (5M) was used for seedling pretreatment and for tTCLs culture, somatic embryos were observed 2 weeks earlier, i.e. after 7 weeks of culture. On the tTCLs from seedlings pretreated with 2,4-d (5M) combined with benzyladenine and zeatin at 0.1 M (BZ), somatic embryos were observed after 6 weeks of culture and the percentage of embryogenesis was higher (62%) than when 2,4-d was used alone for pretreatment (40%). Similar results were also obtained from pretreatment with combinations of 2,4-d (5M) and thidiazuron (TDZ) (0.01, 0.1M). When a combination of 2,4-d (5M) and BZ (0.1M) was used both for seedling pretreatment and for tTCLs culture, both somatic embryos and shoots were observed after only 3 weeks. As the concentration of BZ increased, the percentage of somatic embryogenesis decreased but the percentage of organogenesis increased. Similar responses were obtained with a combination of 2,4-d (5M) and TDZ (0.01M). On the medium containing both NAA (0.3M) and BZ (1M), globular- and heart- stage embryos developed after 4 weeks of culture into cotyledonary-staged embryos which remained dormant after a short elongation of the embryo axis. The importance of seedling pretreatment by growth substances in enhancing somatic embryogenesis is reported.Abbreviations BA
6-benzyladenine
- BZ
combination of BA and zeatin
- 2,4-d
2,4-dichlorophenoxyacetic acid
- MS medium
Murashige and Skoog basal medium
- NAA
a-naphthaleneacetic acid
- TDZ
thidiazuron
- tTCLs
transverse thin cell layers
- TCL
longitudinal thin cell layer 相似文献
7.
Characterization of different decomposition stages of biowaste using FT-IR spectroscopy and pyrolysis-field ionization mass spectrometry 总被引:6,自引:0,他引:6
The decomposition stage and stabilization of organic matter in biowaste (mixture of yard waste and kitchen waste), originating from an open windrow process, were investigated using Fourier transform infrared (FT-IR) spectroscopy and pyrolysis-field ionization mass spectrometry (Py-FIMS). These investigations provided detailed information about chemical constituents and their behavior during the composting process. The chemical compounds were classified by their molecular signals in Py-FIMS. Multivariate statistical analysis revealed, that during the composting process, the group containing lipids, fatty acids and other chemical compounds with aliphatic skeletons changed the most. Corresponding with Py-FIMS findings changes were observed in absorbance bands of infrared spectra that reflect this group of organic compounds: the aliphatic methylene bands at 2925 and 2850cm-1, the band of C=O vibrations of carboxylates at 1640cm-1, the O=H in-plane bend of carboxylic acids, the CO2 stretch of carboxylates and the CH2 group of alkanes at around 1430cm-1. During decomposition these bands decreased up to a steady level that indicated stabilization. The band at 1260–1240cm-1 that can be assigned to the C=O stretch of carboxylic acids or to the C=N stretch of amides and the band of aromatic amines at 1320cm-1 disappeared completely. The nitrate band at 1384cm-1 appeared at a later stage of the composting process. The relative increase of chemical compounds like moieties of lignin, humic acids and tannins in the composted material contributed to the aromatic C=C band at around 1640cm-1. 相似文献
8.
Summary The effect of a non-indole compound, phenylacetic acid (PAA), on the induction of somatic embryogenesis in tissue cultures of geranium (Pelargonium x hortorum Bailey cv. Scarlet Orbit Improved) was investigated. Hypocotyl explants derived from young, dark-grown seedlings were cultured on Murashige and Skoog (1962) medium (MS) supplemented with PAA or IAA (0.01–120 M) alone or in combination with BAP (8 M). Somatic embryogenesis was induced by both PAA and IAA at 0.01–20 M with 8 M BAP, however, the optima differed considerably for the two compounds. Maximal activity of IAA for somatic embryogenesis was found at 0.1–2.5 M, whereas PAA gave best results at 10 and 20 M under identical culture conditions. Higher concentrations (30–120 M) of IAA or PAA in the medium induced callusing in the explants, but the callus was neither embryogenic nor morphogenic.Abbreviations BAP
N6-benzylaminopurine
- IAA
indole-3-acetic acid
- MS
Murashige and Skoog (1962)
- PAA
phenylacetic acid 相似文献
9.
The predacious watermold Zoophagus insidians traps loricate rotifers on short, lateral branches of the main, hyphal axis. These branches or traps are packed at their distal ends with a number of vesicles filled with an electron-dense matrix. Electron micrographs of the mycelium disclose a two-layered wall; the outer layer is electron dense and the inner, electron transparent. The outer dense layer on the tip of the trap is organized into a number of fine ridges and occasional discontinuities. Thin sections through recently trapped rotifers indicate that the cilia of the animals are stuck to the trap by a glue. This adhesive is derived from secretion of the matrix of the vesicles aggregated in the tip of the trap. The secretion mechanism is triggered by the animal and is accompanied by: 1. The separation of the two layers of the wall, 2. fusion of the vesicles with the cell membrane and 3. extrusion of the glue through pits in the tip of the inner wall of the trap. After snaring a rotifer, the previously arrested branch grows as a haustorium into the body cavity of the animal. The host tissues disintegrate within a few hours and appear to be the main nutrient source of the fungus. 相似文献
10.
Nadine Cohen Adam Friedmann Fanny Szafer Avraham Amar Daniel Cohen Prof. Chaim Brautbar 《Immunogenetics》1986,23(4):252-259
In the present report, we used serological, cellular, and restriction fragment length polymorphism (RFLP) to investigate the DR1 haplotype in the Israeli population. We describe an Israeli homozygous typing cell (HTC), HLA-DwLVA, which defines a new lymphocyte-activating determinant associated with Bw65, DR1 and distinct from Dwl. The parents of this donor, non-Ashkenazi Algerian Jews, are first cousins and share HLA-Cw8, Bw65, BfS, DR1, DQw1, DPw4. No specificity could be assigned to HLA-DwLVA using the 91 Ninth Workshop HTCs. Two families and forty unrelated DR1 individuals were studied with DwLVA and a panel of DR1/Dw1 HTCs. HLA-DwLVA showed segregation as a single determinant within families. This new specificity was present in 24 out of 40 (60%) unrelated DR1 individuals, indicating that in the Israeli population DwLVA is the main lymphocyte-defined determinant associated with the serologically defined DRI specificity, in contrast to non-Jewish Caucasoids where DR1 is significantly associated with Dw1. The vast majority of DwLVA-positive carriers were also Bw65 carriers, indicating that Bw65, DR1, DwLVA may represent a typical allele combination in the Israeli population. The RFLP analysis established the correlation of certain RFLPs with Dw1 and DwLVA. In addition, we describe a cluster of RFLPs that may correspond to a new Dw subtype associated with DR1, for which no serological and cellular reagents have been described so far. 相似文献
11.
Angela F. Dulhunty 《The Journal of membrane biology》1989,109(1):73-83
Summary The structure of the triad junction was examined in thin sections of mammalian fast-twitch skeletal muscle. The aims of the experiments were twofold: first, to examine relationships between the contents of the junctional gap and the terminal cisternae that could be significant in excitation-contraction coupling and, second, to look for structures in the transverse tubules that could support a calcium buffer system. Procedures known to stabilize cytoskeletal elements were used in an attempt to retain the original structure. Feet, pillars and bridges were often seen side by side in the same junction. In one such junction, the average center-to-center spacing between four bridges was 30.9±1.7 nm and between five foot-like structures was 29.2±1.4 nm. The subunit structure of the feet could be seen in many sections. The lumen of the terminal cisternae was filled with a tetragonal network of calsequestrin which formed parallel strands near the junctional membrane, in register with the feet. The strands overlay the area occupied by rods seen in freeze-fracture replicas of terminal cisterna membrane. The contents of the transverse tubules were aggregated into bands, or tethers, which extended across the short axis of the tubule at regular intervals of about 30 nm. The tethers consisted of flattened discs, stacked across the long axis of the tubule, aligned with the junctional feet. Lanthanum staining of the tethers indicated cationic binding sites that could buffer luminal calcium ion concentration in the vicinity of the voltage sensor for contraction. It is suggested (i) that the control of calcium concentration near the voltage sensor is necessary for normal activation, (ii) that feet, pillars and bridges are different images of a spanning structure, and (iii) that the regular alignment of tethers, feet and calsequestrin is functionally significant in excitation-contraction coupling. 相似文献
12.
Three Andean tetraploid potato genotypes (2n=48) and 7 anther-derived dihaploids (2n=24) originating from two of the tetraploids were used in anther culture. Relative number of embryos/vial was significantly higher when the anther culture media was gelatinized with 3% potato starch than when Gelrite or wheat starch (3%) were used as gelatinizing agents. The degree of anther culture response varied between tetraploids but also within a group of related dihaploids. Additionally, the embryo production of individual genotypes, tetraploids as well as dihaploids, was dependent on the incubation temperature (10, 15, 20, 25, 30°C) of the anther culture. The incubation temperature of the anther culture was also important for the regeneration rate. Direct regeneration was mostly stimulated when the anther culture was incubated at 20°C.Abbreviations BAP
6-benzylaminopurine
- IAA
indole-3-acetic acid 相似文献
13.
Summary In normal, non-expanding toad epidermis more cells are produced than needed to replace cells lost by moulting. By implication, cell deletion additional to moulting must take place. This paper deals with the mechanisms by which the surplus of cells is deleted, taking advantage of the fact that the ratio between cell birth rate (K
b) and the rate of desquamation (K
d), which in normal toads is 2 to 3, can be manipulated. In toads deprived of the pars distalis of the pituitary gland it is decreased to 0.2 to 0.3, and in toads with hydrocortisone pellets implanted into the subcutaneous lymph space it is increased to 7 to 10. Thus, structures candidates for the morphological manifestation of the deletion process should occur rarely in toads in which the pars distalis has been removed and frequently in toads with hydrocortisone pellets implanted. Categorization and enumeration of such structures by light microscopy in the epidermis from operated, normal, and hormone-treated toads were performed. The incidence of structures referred to as dark cells and omega-figures were found to correlate relatively well with the K
b/Kd-ratio. A subsequent ultrastructural analysis — on a cell-by-cell basis — of dark cells showed these to reflect various stages of apoptosis. The duration of the apoptotic process was calculated to be approximately 7 h. Light- and electron microscopy of omega-figures combined with histochemical observations of PSA-lectin binding were interpreted as reflecting a release of cells from the basal epidermis and their final elimination within the dermis. It is concluded (i) that apoptosis is an important mechanism of controlled cell deletion, (ii) that emigration to, and elimination in, the dermis is a possible deletion mechanism, and (iii) that necrosis is unlikely to play a role in controlled cell deletion.Supported in part by the Danish National Science Research Council (grant no. 11-6498) (PB)Part of this work was presented at the XVth Meeting of the European Study Group for Cell Proliferation, Sundvollen, Norway, 16–20 September 1987 相似文献
14.
Robert E. Bartholomew 《Culture, medicine and psychiatry》1990,14(4):455-494
This study provides a critical historical review and analysis of the variety of human expressions which have been erroneously labeled under the grandiose category mass hysteria. It is argued that Western science reductionist approaches to the classification of mass hysteria treat it as an entity to be discovered transculturally, and in their self-fulfilling search for universals systematically exclude what does not fit within the autonomous parameters of its Western-biased culture model, exemplifying what Kleinman (1977) terms a category fallacy. As a result of objectivist methodologies, the etiology of actions labeled as mass hysteria is typically viewed as deviant, irrational or abnormal behavior resulting from a malfunctioning proper social order. However, what constitutes the correct social order is a function of a researcher's historical sociocultural and/or scientific milieu. This study reviews the problem, advocating Geertz's (1973) culturally relativistic approach to understanding various cross-cultural behavior that is sensitive to and tolerant of the unique context and milieu of participants. Mass or epidemic hysteria is viewed as an invention of Western psychiatry and should be abandoned and replaced with the term collective exaggerated emotions. Instead of attempting to discover a neatly packaged, unitary external disease entity, the focus of a meaning-oriented approach emphasizes the deciphering of foreign realities, semantic networks and symbol systems. 相似文献
15.
Yuqiang Sun Xianlong Zhang Shuangxia Jin Shaoguang Liang Yichun Nie 《Plant Cell, Tissue and Organ Culture》2003,75(3):247-253
A simple and efficient method for high frequency somatic embryogenesis and plant regeneration from hypocotyl-derived cultures and suspension cultures of Gossypium klotzschianum Anderss, a wild, diploid species of cotton is described here. Embryogenic cultures were induced from hypocotyl sections on MSB medium with 0.9 M 2,4-D and 2.32 M kinetin. MSB medium containing 0.045 M 2,4-D, 0.93 M kinetin, 2.46 M IBA promoted embryogenic culture proliferation and embryo development. Suspension cultures with 0.23 M 2,4-D and 0.93 M kinetin also produced many embryos. Somatic embryos cultured on MSB medium with PGRs produced secondary embryos, and embryos developed into normal plantlets on PGR-free MSB medium. Regenerated plantlets were transferred onto the quarter-strength MSB medium with 0.5% active charcoal to avoid recallusing. Hypocotyls were better than cotyledons for culture induction and plant regeneration. 2,4-D and kinetin were essential for culture induction and maintenance. 相似文献
16.
I. E. Pristyazhnyuk S. A. Temirova A. G. Menzorov A. A. Kruglova N. M. Matveeva O. L. Serov 《Russian Journal of Developmental Biology》2005,36(2):119-126
Chromosome segregation of the parental chromosomes was studied in 20 interspecific hybrid clones obtained by fusion of Mus musculus embryonic stem cells with Mus caroli splenocytes. FISH analysis with labeled species specific probes and microsatellite markers was used for identification of the parental chromosomes. Cytogenetic analysis has shown significant intra- and interclonal variability in chromosome numbers and ratios of the parental chromosomes in the hybrid cells: six clones contained all M. caroli chromosomes, nine clones showed moderate segregation of M. caroli chromosomes (from 1 to 7), and five clones showed extensive loss of M. caroli chromosomes (from 12 to complete loss of all M. caroli autosomes). Both methods demonstrated cryptic segregation of the somatic partner chromosomes. For instance, five clones with near-tetraploid chromosome sets contained only few M. caroli chromosomes (from 1 to 8). The data obtained suggest that the tetraploid chromosome set per se is not a sufficient criterion for conclusion on the absence of chromosome loss in the hybrid cells. Note that cryptic chromosome segregation occurred at a high frequency in the examined hybrid clones. Thus, cryptic segregation should be borne in mind for assessing pluripotency and genome reprogramming of embryonic stem hybrid cells.__________Translated from Ontogenez, Vol. 36, No. 2, 2005, pp. 151–158.Original Russian Text Copyright © 2005 by Pristyazhnyuk, Temirova, Menzorov, Kruglova, Matveeva, Serov. 相似文献
17.
A presumed XY chromosome pair is described fromt estis squashes from the mesopelagic deep-sea fish Bathylagus wesethi, whose 2N chromosome number was determined as 34-XY. Although the metacentric X-chromosome is the largest in the entire compliment, the Y is the smallest and only acrocentric element. The positive heteropycnosis of the sex elements was not easily distinguishable in the nuclei of first meiotic prophase. Tetraploid nuclei were observed in peripheral supporting cells of the testis. Males of at least two other congeners have similar karyotypes. 相似文献
18.
Dr. M. E. Stoeckel S. Schimchowitsch J. C. Garaud G. Schmitt H. Vaudry M. J. Klein A. Porte 《Cell and tissue research》1985,242(2):365-370
Summary The immunogold technique, employing antisera with clear-cut specificities, was used to localise different processing stages of pro-opiomelanocortin (POMC) in rabbit melanotropic cells. While the antiserum against
3-MSH labelled all the secretory granules including intrasaccular condensations in the Golgi apparatus, antisera against -MSH only labelled extra-Golgi secretory vesicles (SV). All extra-Golgi SV were likewise labelled with the three antisera against -MSH used, despite their different specificities for the desacetylated, N-acetylated or C-amidated forms of the peptide. The antibody against -endorphin also labelled the extra-Golgi SV, while only some SV were labelled with the antibody against -endorphin. These results correlate with biochemical data in favour of mainly — if not exclusively — intragranular processing of POMC. Except for 3-MSH, the cleavage of which could coincide with Golgi packaging of secretory material, other post-translational modifications of the precursor seem to occur when SV are discharged outside the Golgi area. The cleavage of -endorphin appears to be a later step in POMC processing, occurring in some mature SV. 相似文献
19.
V. R. Reddi V. Padmaja 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1982,61(1):35-40
Summary The seven possible primary trisomics of Petunia (2 n= 14) located in the progenies of triploid, hypertriploid and hypotriploid plants were distinguished from one another and from diploid on the basis of cytological and morphological criteria. They were provisionally named as Oval, Semi, Slender, Pseudonormal, Arrow, Narrow and Giant. In three of the trisomics, the extra chromosome was identified for the first time at pachytene stage. Postpachytene studies revealed no precise relationship between the length of extra chromosome and the frequency of multiple association. 相似文献
20.
Michael Hesse 《Plant Systematics and Evolution》1980,134(3-4):229-267
Some closely related members of the monocotyledonous familiesAlismataceae, Liliaceae, Juncaceae, Cyperaceae, Poaceae andAraceae with variable modes of pollination (insect- and wind-pollination) were studied in relation to the ultrastructure of pollenkitt and exine (amount, consistency and distribution of pollenkitt on the surface of pollen grains). The character syndromes of pollen cementing in entomophilous, anemophilous and intermediate (ambophilous or amphiphilous) monocotyledons are the same in principal as in dicotyledons. Comparing present with former results one can summarize: 1) The pollenkitt is always produced in the same manner by the anther tapetum in all angiosperm sub-classes. 2) The variable stickiness of entomophilous and anemophilous pollen always depends on the particular distribution and consistency of the pollenkitt, but not its amount on the pollen surface. 3) The mostly dry and powdery pollen of anemophilous plants always contains a variable amount of inactive pollenkitt in its exine cavities. 4) A step-by step change of the pollen cementing syndrome can be observed from entomophily towards anemophily. 5) From the omnipresence of pollenkitt in all wind-pollinated angiosperms studied one can conclude that the ancestors of anemophilous angiosperms probably have been zoophilous (i.e. entomophilous) throughout. 相似文献