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1.
Data are presented for the first time on the quantitative distribution of pink salmon yearlings in the autumn period in the northwestern Sea of Japan that characterize one of the stages of salmon migrations toward wintering grounds. Data are presented concerning pink salmon wintering in near-bottom water layers near southwestern Sakhalin.Original Russian Text Copyright © 2005 by Biologiya Morya, Temnykh, Loboda, Ilinskii.  相似文献   

2.
Wheat microspores mechanically isolated from the anthers before culture and isolated from the anthers during the hole culture period in a chemically defined medium resulted in proembryos, embryos and finally plants. Of the four genotypes included, all responded with proembryos, and the two spring wheats Ciano and Walter gave rise to macroscopic embryos and plants. The frequency of embryo regeneration and the frequency of albino plants in both Ciano and Walter was in accordance with previously obtained results with anther culture derived material.Abbreviations 2,4-d 2,4-dichlorophenoxy acetic acid - NAA 1-naphthaleneacetic acid  相似文献   

3.
Unlike most marine teleosts, the coral reef-dwelling spiny damsel, Acanthochromis polyacanthus, lacks a pelagic larva dispersal phase and represents one of few examples of self recruitment onto a natal reef by a marine teleost immediately after hatching. Benthic eggs are protected by the parents, and upon hatching the young remain under parental care for several months. Visual morphogenesis of spiny damsel embryos and juveniles was examined to evaluate the potential visual capabilities of the young after emergence onto the reef. The optic primordia were visible in the embryo as hollow spheres of undifferentiated neuroblasts 2 days after fertilization (daf). Visual morphogenesis proceeded rapidly thereafter in the embryo such that at hatching (between 10 and 12daf) gross visual morphology was consistent with that reported in the majority of juvenile marine teleosts, reflecting direct development of the retina of the spiny damsel within the egg. At hatching, the outer nuclear layer comprised 2 classes of photoreceptors; cones and rods. Tangential sections of the retina revealed a square cone mosaic in which 4 double cones surrounded a single cone. This arrangement remained unchanged in all later life history intervals examined. Absolute eye size was large compared to larvae of marine pelagic spawners. Eye and lens diameters increased from 0.69 and 0.23mm, respectively, on the day of hatching (12daf), to 3.77 and 1.52mm, respectively, in a fish 131daf. Angular density of cones increased from 0.25 cones 10 visual arc–1 in an embryo 8daf, to 1.14 cones 10 visual arc–1 in a fish 131daf, demonstrating the potential for significant increase in spatial resolution with increasing eye size. Convergence ratios of cones to ganglion cells remained relatively constant from the time of hatching, suggesting that the determinate ganglion cell photopic receptive field was established early in development. The increase in the convergence ratios of rods: ganglion cells from 1.4 in the late stages of embryogenesis (10daf; 2 days prior to hatching) to 4.9 in a fish 103daf, demonstrated increasing scotopic ganglion cell receptive field size, with increasing age. This was a result of rod cell addition with growth. An increase in the angular density of rods from 0.18 rods 10 visual arc–1 in an embryo 8daf, to 4.07 rods 10 visual arc–1 in a fish 131daf, and the increase in mean scotopic light path-length from 13.3±1.1m in an embryo 8dpf, to 55±5.2m a fish 22dpf, collectively indicate the potential for increasing scotopic sensitivity during growth. On the basis of visual morphology it is predicted that newly hatched spiny damsel juveniles have substantially greater visual capabilities than first feeding larvae with a pelagic dispersal phase. In addition, we propose that the developmental trajectory of the spiny damsel is different from that of pelagic dispersing larvae and does not simply reflect displacement along a common developmental continuum by an extended embryonic duration.  相似文献   

4.
Lentil is a protein-rich pulse, grown mainly in developing countries as a rain-fed crop in nutrient-poor soils. Hence, the importance of root traits for efficient capture of soil nutrients and water can be crucial to its economical yield. Little is known about the lentil root system and even less about its relationship to grain yield. We compared the root system of two Bangladeshi lentil varieties, Barimasur-3 (BM-3) and Barimasur-4 (BM-4), in a pot experiment and related it to their multi-location grain yield in the fields. BM-4 maintained faster root development both at an early growth stage (20days after sowing) and at flowering (60days) compared to BM-3. The roots of BM-4 penetrated the 25cm depth of the soil profile after 19±1days and while those of BM-3 took 24±2days to reach the same depth. The roots of BM-4 were covered with denser (26±3mm–1) and longer (0.48±0.11) root hairs than BM-3 (density 17±2mm–1, length 0.32±0.09mm). The differential presence of root hairs increased the effective length of root system of BM-4 by 12 times and that of BM-3 by five times. The lentil varieties did not differ in their ability to induce pH change and acid phosphatase activity in rhizosphere. In the pot experiment, the uptake of macro-nutrients (K, P, Ca, and Mg) as well as micro-nutrients (Fe, Mn, Zn, Cu, B and Mo) by BM-4 was significantly higher, compared to BM-3. The varieties produced the same amount of shoot biomass. At five of six agro-ecological distinct field locations in Bangladesh, BM-4 gave significantly higher (10–20%) grain yield than BM-3. Linked with the higher grain yield, the benefit-cost ratio (BCR) of BM-4 was 3.14 and that of BM-3 were 2.62, indicating that BM-4 provided better return per unit investment, compared to BM-3, supported by the better root morphology and higher nutrient uptake. This may be one of the reasons supporting the popularity and preferred adoption of BM-4 among the Bangladeshi farmers, who grow lentil mainly on nutrient-poor soils. The results indicate the benefits of selection and breeding for superior root traits for better agro-economics.  相似文献   

5.
We report the cloning of a cDNA and two corresponding -globin genes of the Atlantic salmon (Salmo salar L.) as well as two genes for -globins. Nucleotide sequence analysis of the cDNA shows that the predicted -globin peptide comprises 148 amino acids with a calculated molecular mass of 16,127 Da and an overall amino acid similarity of 40–50% to higher vertebrates and 60–90% to fish sequences. The study of the genomic organization of - and -globin genes shows that, as is the case in Xenopus, the salmon genes are adjacent. Two sets of linked - and -globin genes were isolated and restriction-enzyme polymorphisms indicate that they belong to two distinct loci, possibly as a result of the salmon tetraploidy. In each locus the - and -globin genes are oriented 3 to 3 relative to each other with the RNA coding sequences located on opposite DNA strands. This is the first evidence for this type of arrangement found for globin genes. Moreover, while the linkage found in salmon and Xenopus supports the hypothesis of an initial tandem duplication of a globin ancestor gene, our results raise the question of the actual original orientation of the duplicated genes. Correspondence to: F. Gannon  相似文献   

6.
Summary. Cysteine dioxygenase (CDO) plays a critical role in the regulation of cellular cysteine concentration. Because multiple forms of CDO (23kDa, 25kDa, and 68kDa) have been claimed based upon separation and detection using SDS-PAGE/western blotting (with antibodies demonstrated to immunoprecipitate CDO), we further investigated the possibility of more than one CDO isoform. Using either rabbit antibody raised against purified rat liver CDO or against purified recombinant his6-tagged CDO (r-his6-CDO) and using 15% (wt/vol) polyacrylamide for the SDS-PAGE, we consistently detected the 25kDa band, but never detected a 68kDa band, in rat liver, kidney, lung and brain. Nondenatured gel electrophoresis of r-his6-CDO yielded a molecular mass estimate of 25.7kDa and no evidence of dimerization. Mass spectrometry of r-his6-CDO yielded two peaks with molecular masses of 24.1kDa and 24.3kDa. Anion-exchange FPLC of r-his6-CDO also gave two peaks, with the first containing CDO that was 7.5-times as active as the more anionic form that eluted second. When the two peaks recovered from FPLC were run on SDS/PAGE, the first (more active) CDO fraction yielded two bands (perhaps as an artifact of SDS/PAGE), whereas the second (less active) CDO fraction yielded only the 23kDa band. We conclude that the physiologically active form of CDO is the 25kDa (i.e., 23.5kDa based on mass spectrometry) monomer and that this active form is probably derived by post-translational modification of the 23kDa gene product.  相似文献   

7.
Intragenic polymorphism of the human insulin gene (INS) was investigated in Korean subjects. The 1.9 kb INS sequence, including the 5 to 3 flanking regions, was amplified using the polymerase chain reaction (PCR), and analyzed by direct sequencing. All nucleotide sequences in the coding regions were the same as INS sequences previously reported, and four nucleotides, at positions +216, +1045, +1367, and +1380 in the non-coding regions, were found to be polymorphic. In addition to the previously identified polymorphic alleles l (A-C-C-C) and 1 (T-G-T-A), new nucleotide arrangements were also identified and designated 4 (A-C-C-A), 5 (A-G-C-C), 6 (A-C-T-C), and 2 (T-C-C-C). It was concluded that the new alleles may originate by intragenic recombination within INS during chromosomal crossing-over between the 1 and 1 alleles. The allele 1 was the predominant form in our sample; the new variant alleles, as well as allele 1, appeared to be much less frequent in INSs genes of the Korean subjects studied. Furthermore, the new alleles were detected only in heterozygous form. These results suggest that intragenic recombination can account for allelic divergence in INS.  相似文献   

8.
Summary Report of the case of a boy, presently 9 years old, who showed symptoms of an 18p- syndrome, which was proven cytogenetically to be a Klinefelter syndrome with 18/21 translocation. The chromosome examination was conducted with the G-banding technique. The findings according to the nomenclature of the Paris Conference of 1971 are: 46,XY, +(X),t(18qtercen21qter).
Zusammenfassung Es wird über einen jetzt 9 Jahre alten Knaben berichtet, bei dem die Symptome eines 18p-Syndroms bestehen und cytogenetisch ein Klinefelter-Syndrom mit 18/21-Translokation nachgewiesen wurde. Die Untersuchung der Chromosomen erfolgte mit der G-Banden-Technik. Bei Benutzung der Nomenklatur der Paris Conference 1971 heißt der Befund: 46,XY,+(X),t(18qtercen21qter).


Professor W. Hirsch died on Febr. 8, 1974.  相似文献   

9.
The effect of Fe(III) deficiency on qualitative and quantitative changes in pigment composition in Phaeodactylum tricornutum Bohlin was demonstrated by HPLC and AAS. Maximum content of pigments showed the diatom cells incubated at the optimum iron concentration, i.e., 10 M. The contents of chlorophyll a, chlorophyll c 1+c 2, fucoxanthin, diadinoxanthin and ,-carotene were 109.99, 20.16, 40.39, 1.29 and 1.48 fg per cell, respectively. The results obtained showed that Fe(III) affected qualitative and quantitative pigment composition in P. tricornutum. The content of individual pigments, proportions between accompanying pigments and their ratios to chlorophyll a were important indicators of phytoplankton response to iron stress. The strong reduction in ,-carotene content, several times (2–5) increase in diadinoxanthin level as compared to ,-carotene, and high amount of diadinoxanthin in relation to chlorophyll a were observed in algae growing at very low Fe(III) concentrations, 0.001 and 0.01 M. The data suggested that phytoplankton pigments could be a potential physiological marker.  相似文献   

10.
Summary One system of monomeric adenylate kinase isozymes, designated ADK, was observed in Triticum aestivum and in five diploid Triticeae species. The gene loci Adk-a, Adk-b and Adk-d were located on 7AL, 7BL and 7DL Triticum aestivum cv Chinese Spring chromosomal arms, respectively. Adk gene loci were also located on the 7RL chromosomal arm of Secale cereale cv Ailés, the 7H chromosome of Hordeum vulgare cv Betzes, 7X of Agropyron intermedium, 7E of Elytrigia elongata and CSU-E of Aegilops umbellulata. The results suport the notion of the conservation of gene synteny groups within Triticeae species.  相似文献   

11.
Two bioindication scales of the degree of eutrophication based on aquatic macrophyte communities were established in two types of running waters free of organic matter, the one in acidic soft waters (pH 5.5–7.0, conductivity 40–110 S.cm–1), the other in alkaline hard waters (pH 7–8, conductivity 500–900 S.cm–1). We show that the main determining factor of the macrophyte distribution is the nutrient level (trophy), especially the level of phosphate and ammonia. The acidic scale, with increasing pH, includes four stages ranging from oligotrophic to eutrophic level (traces to 300 g.l–1 N-NHinf4p+ and P-PO4 3–), while the alkaline scale at constant pH comprises six stages of a trophic gradient. For the most part, the floristic composition found in the two sequences is different and depends on conductivity and alkalinity variation. However, some species occur in the two scales and may reflect differences in the trophic level, depending on whether the waters are alkaline or acidic. This change of trophic level for these species is discussed.  相似文献   

12.
This paper explores the social and cultural organization of Iranian emotional discourse and its transformation in post-revolutionary Iran. First, the Moharram dramas we participated in during field research are described, indicating how these performances organized a prototypical view of the social order, the self, and the passions. Using Kapferer's distinction between transcendental and transformative rituals, we argue that these dramas were traditionally organized as transcendental rites. Second, data on grieving rituals and depressive illness among Iranians is introduced, focusing on the transformative qualities of mourning rites and suggesting an interpretation of depression as a failure of the work of culture. Third, the appropriation of these symbolic forms of society, self, and the emotions by the current Iranian Islamic state and the role of the state in defming the meaning and legitimacy of emotions and their expression is analyzed.  相似文献   

13.
Yue GH  Beeckmann P  Geldermann H 《Genetica》2002,114(2):113-119
During genotyping of 38 microsatellites for QTL (quantitative trait loci) mapping in three F2 swine populations, five mutant alleles were detected in a total of 66,436 parent-offspring transfers of microsatellite alleles, which gives an overall mutation rate of 7.52×10–5 per locus per generation. No significant (P<0.05) association between mutation rates and other factors (i.e., GC contents in the flanking regions, heterozygosity, and repeat number) was revealed. Detailed sequencing showed that four out of five mutant alleles were caused by insertions of one to five repeats, respectively. The other mutant allele was produced by either an insertion of three repeats or a change of 30 base pairs (a deletion of 16 CT repeats and an insertion of one CA repeat). An insertion of one base pair in the flanking region of a microsatellite was also detected. Together, these data indicate that expansions are more common than contractions among microsatellites and that the mutation processes are very complicated, do not fit with the strict stepwise mutation model and may vary from locus to locus.  相似文献   

14.
Somatic embryogenesis and plant regeneration from immature zygotic embryos was achieved for saw palmetto (Serenoa repens (Bartr.) Small). Embryos, isolated from immature fruit of native-grown plants, were cultured on Murashige and Skoog medium plus 0.15% (w/v) activated charcoal and supplemented with 452 M 2,4-dichlorophenoxyacetic acid (2,4-D) and 14.7 M N6-(2-isopentenyl)adenine (2iP). Clusters of somatic embryos developed from all immature zygotic embryos 5 weeks after culture initiation. After 12 weeks, explants were transferred to the same medium with the amount of 2,4-D reduced to 90.4 M which resulted in somatic embryo proliferation. Somatic embryos were then transferred to the basal medium containing 0.9, 9 M thidiazuron (TDZ), or no growth regulator for conversion into plantlets. The 9 M TDZ treatment was ineffective for plant regeneration. However, 12% of the embryos subcultured on 0.9 M TDZ were able to produce complete plantlets. Shoot production was obtained from 35% of the embryos subcultured in the absence of growth regulators. Rooting (100%) was achieved when these shoots were transferred onto medium containing 22.2 M -naphthaleneacetic acid (NAA).  相似文献   

15.
Gal'chenko  V. F.  Dulov  L. E.  Cramer  B.  Konova  N. I.  Barysheva  S. V. 《Microbiology》2001,70(2):175-185
The biogeochemical processes of methane production and oxidation were studied in the upper horizons of tundra and taiga soils and raised bogs and lake bottom sediments near the Tarko-Sale gas field in western Siberia. Both in dry and water-logged soils, the total methane concentration (in soil particles and gaseous phase) was an order of magnitude higher than in the soil gaseous phase alone (22 and 1.1 nl/cm3, respectively). In bogs and lake bottom sediments methane concentration was as high as 11 l/cm3. Acetate was the major precursor of the newly formed methane. The rate of aceticlastic methanogenesis reached 55 ng C/(cm3day), whereas that of autotrophic methanogenesis was an order of magnitude lower. The most active methane production and oxidation were observed in bogs and lake sediments, where the 13C values of CO2were inversely related to the intensity of bacterial methane oxidation. Methane diffusing from bogs and lake bottom sediments showed 13C values ranging from –78 to –47, whereas the 13C value of carbon dioxide ranged from –18 to –1. In these ecosystems, methane emission comprised from 3 to 206 mg CH4/(m2day). Conversely, the dry and water-logged soils of the tundra and taiga took up atmospheric methane at a rate varying from 0.3 to 5.3 mg CH4/(m2day). Methane consumption in soils was of biological nature. This was confirmed by the radioisotopic method and chamber experiments, in which weighting of methane carbon was observed (the 13C value changed from –51 to –41).  相似文献   

16.
Summary Characteristics of inorganic carbon assimilation by photosynthesis in seawater were investigated in six species of the Fucales (five Fucaceae, one Cystoseiraceae) and four species of the Laminariales (three Laminariaceae, one Alariaceae) from Arbroath, Scotland. All of the algae tested could photosynthesise faster at high external pH values than the uncatalysed conversion of HCO 3 - to CO2 can occur, i.e. can use external HCO 3 - . They all had detectable extracellular carbonic anhydrase activity, suggesting that HCO 3 - use could involve catalysis of external CO2 production, a view supported to some extent by experiments with an inhibitor of carbonic anhydrase. All of the algae tested had CO2 compensation concentrations at pH 8 which were lower than would be expected from diffusive entry of CO2 supplying RUBISCO as the initial carboxylase, consistent with the operation of energized entry of HCO 3 - and / or CO2 acting as a CO2 concentrating mechanism. Quantitative differences among the algae examined were noted with respect to characteristics of inorganic C assimilation. The most obvious distinction was between the eulittoral Fucaceae, which are emersed for part of, or most of, the tidal cycle, and the other three families (Cystoseiraceae, Laminariaceae, Alariaceae) whose representatives are essentially continually submersed. The Fucaceae examined are able to photosynthesise at high pH values, and have lower CO2 compensation concentrations, and lower K1/2 values for inorganic C use in photosynthesis, at pH 8, than the other algae tested. Furthermore, the Fucaceae are essentially saturated with inorganic C for photosynthesis at the normal seawater concentration at pH 8 and 10°C. These characteristics are consistent with the dominant role of a CO2 concentrating mechanism in CO2 acquisition by these plants. Other species tested have characteristcs which suggest a less effective HCO 3 - use and CO2 concentrating mechanism, with the Laminariaceae being the least effective; unlike the Fucaceae, photosynthesis by these algae is not saturated with inorganic C in normal seawater. Taxonomic and ecological implications of these results are considered in relation to related data in the literature.  相似文献   

17.
Summary Taxusbrevifolia is the source of paclitaxel (Taxol®), an anticancer drug. A method for regeneration ofTaxus brevifolia from immature zygotic embryos via somatic embryogenesis is described. Embryogenic callus tissues were obtained by culturing immature zygotic embryos on Lloyd and McCown medium (MCM) supplemented with 160 M 2,4-dichlorophenoxyacetic acid (2,4-D) + 5 M benzylaminopurine (BA) + 5 M naphthaleneacetic acid (NAA) for 4 weeks. Putative embryoids were obtained following transfer of cultures to MCM medium supplemented with 4 M BA + 5 M kinetin + 1 M NAA for 6 to 8 weeks. Conversion of embryos was obtained on MCM medium supplemented with 40 M abscisic acid (ABA) + 1% activated charcoal. Development of bipolar structures with recognizable shoot and root apices was observed in somatic embryos. Five percent of somatic embryos were regenerated into plantlets on half-strength growth regulator-free MCM medium.  相似文献   

18.
Stanniocalcin-immunoreactive cells were localized in the corpuscles of Stannius of a holostean fish, the garpike (Lepisosteus osseus), using antisera against salmon and trout stanniocalcins and the peroxidase-antiperoxidase and protein A-gold immunohistochemical methods. The stanniocalcin-immunoreactive cells were periodic acid-Schiff-positive, and antibody staining was abolished if the antiserum was preabsorbed with corpuscle homogenate. Immunocytochemistry revealed two reactive cell types in the glandular parenchyma, and immunoreactivity was confined to the secretory granules. Staining of the granules was also abolished when the antisera were blocked with crude corpuscle homogenate. When corpuscle extracts from garpike were subjected to sodium dodecyl sulphate-polyacrylamide gel electrophoresis and Western blot analysis, a single dense band was evident with a molecular weight of 68 kDa under non-reducing conditions, whereas three bands were observed (29, 31, and 34 kDa) under reducing conditions. Staining of all bands disappeared following preabsorption of the antiserum with salmon stanniocalcin, trout stanniocalcin, or garpike corpuscle extract. The results are compared with stanniocalcins from another extant holostean, the bowfin (Amia calva), and from more modern bony fishes, the teleosts.  相似文献   

19.
Regeneration of peach plants from callus derived from immature embryos   总被引:9,自引:0,他引:9  
Summary Peach plants were repeatedly regenerated from immature embryos but not from callus derived from mature embryos. A white, nodular, highly regenerative callus was obtained when friable, primary callus from immature embryos was transferred from medium containing 4.5 M 2,4-dichlorophenoxyacetic acid and 0.44 M benzyladenine (BA) to media containing 0.27 M -naphthaleneacetic acid (NAA) and 2.2 M BA. This callus retained its morphogenetic potential for a minimum of three subcultures. Green nodular callus, that lacked regenerative capacity, was produced from primary callus derived from mature embryos. Maximum regeneration of shoots occurred when highly regenerative callus was transferred to a medium in which the NAA concentration was reduced five times and the BA concentration was increased two times. Regenerated shoots were rooted in the dark on a medium containing 28.5 M indoleacetic acid. Cytogenetic analysis of regenerated plants indicated that all plants were diploid, 2n = 2x = 16. Phenotypic evaluation of regenerated plants, grown under field conditions, is now in progress.  相似文献   

20.
The development of the frontal bone and the formation of the first head scales are described during post-embryonic ontogeny of Hemichromis bimaculatus, using light and transmission electron microscopy. The frontal bone originates close to the cartilaginous taenia marginalis in a loose mesenchymal cell condensation (=primordium) lying 1 m from the epidermis with which it establishes no cell contacts. The anlage appears at 4.2 mm standard length (SL) in the form of the membranodermal component of the bone, and extends first over the brain and then over the eye; the neurodermal component forms later to surround the supraorbital canal. The first head scales appear at 10.0 mm SL in a dense cell condensation (papilla) adjoining the epidermal-dermal junction and, once formed, remain in this position. In both organs, the initial matrix is similarly composed of woven-fibred bone that soon mineralizes in a similar manner to other dermal elements. In some areas of the frontal bone, parallel-fibred bone is deposited unequally on both surfaces, whereas isopedine is deposited in scales on the deep surface only. Osteoblastic features confirm this eccentric growth. Differences in the shape, organization and localization of the mesenchymal condensations giving rise to the frontal bone and to the scale reflect the existence of two types of dermal cell condensations. Our data are compared with those available for the post-cranial dermal skeleton of fishes both from a developmental and structural viewpoint. Structural differences in the matrices of the frontal bone and scales are discussed in a phylogenetic perspective.  相似文献   

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