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1.
J. Lodder 《Antonie van Leeuwenhoek》1947,12(1-4):273-280
III Conclusion and Summary
Zygosaccharomyces Marxianus andSaccharomyces macedoniensis belong to the same species. This species is met with in the haplophase (Z. Marxianus) as well as in the diplophase (S. macedoniensis). It was possible to bring this yeast from the haplophase into the diplophase and vice versa. By keeping this yeast during long times on maltagar it showed a tendency to change from the haplophase into the diplophase, but not into the opposite direction.It seems quite possible thatHansen, who did not describe a conjugation in this yeast, had met with the diplophase.It has been once more emphasized — at whichWinge andLaustsen and alsoLindegren andLindegren have pointed —, that the genusZygosaccharomyces is no valid genus.The yeast studied here belongs to the genusSaccharomyces and must be designated with the original name given to it byHansen:Saccharomyces Marxianus.For the sake of completeness it is mentioned here that also an imperfect stage ofS. Marxianus has been describedviz., Candida macedoniensis (A. Castellani) Berkhout (I).Saccharomyces fragrans Beijerinck has to be considered as its synonym. 相似文献
2.
T. R. Deason P. C. Silva S. Watanabe G. L. Floyd 《Plant Systematics and Evolution》1991,177(3-4):213-219
Komárek has recently reviewed the various species assigned to the green algal genusNeochloris
Starr (Chlorococcales, Chlorococcaceae) and removed those with uninucleate vegetative cells to a new genus,Ettlia.
Watanabe & Floyd, unaware ofKomárek's work, also reviewed the species ofNeochloris and distributed them among three genera—Neochloris, Chlorococcopsis gen. nov., andParietochloris gen. nov.—on the basis of details of the covering of the zoospore and the arrangement of the basal bodies of the flagellar apparatus. This paper reconciles these two treatments and makes additional recommendations at the ranks of genus, family, order, and class. 相似文献
3.
Summary The stem-gall caused byProtomyces macrosporus
Ung. is a common disease of coriander which is an important spice crop of India and other countries. For the first time, it has been possible to obtain at least a partial field control of this disease, through seed treatment with thiram at the dose of 0.25 kg per 100 kg of seed. There are indications that better control is possible by combining seed and soil treatments with thiram. Seed treatment with TCNA — an experimental fungicide — may prove to be effective at a dose of 0.5 kg per 100 kg of seed.The authors are grateful to Dr.N. K. A. Rao, Dean, College of Agriculture and Dr.R. L. Paliwal, Director of Experiment Station, for their help. The Junior authors thank U. S. Agency for International Development (University of Illinois) for the award of graduate traineeships. 相似文献
4.
Different stages of megaspore and megasporangial development inSelaginella argentea (Wallich)Spring,S. bigelowii
Unerw., andS. kraussiana (Kze.)A. Br. have been seen and studied. Megaspore wall units give positive reactions for polysaccharides and protein in young megaspores, and become the thick and resistant wall typical of the genus only later.—Units forming the exospore and the spaces between units enlarge from widths of 5–10nm early during development up to over 200 nm at pregermination stages. The spaces enlarge first. Initially they are circular and mostly about 70 nm in diameter. Later, spaces toward the inner part of the exospore enlarge more than those near the outer surface. During pregermination, wall spaces range in size from 4 to 50 times the width of units with the larger spaces located near the inner surface. As a result the exospore would be under tension to spring outward during germination when the laesurae are lysed.—A gap in the exospore, shaped like a half-moon in polar sections, forms in equatorial and distal portions of the spore. This gap becomes enormous, three times the volume of the central space plus the mesospore, and is filled with lipids and other nutrients. Late in development, during the period of tapetal cell degeneration, the gap contents are moved into the central space and the gap is closed.—Late in development the mesospore is degraded. Its products, along with gap contents, seem to be added to the contents of the central cavity and appear as reserve storage globules. A primary wall-like endospore is formed during this period, at the inner surface of the exospore. During germination this endospore develops further at its inner surface.—Changes in the size and shape of megasporangia occur independently of the size of megaspores.Megaspore development inSelaginella. II. For first part seeMorbelli & Rowley (1993). 相似文献
5.
Quantification of the histochemical reaction for alkaline phosphatase activity using the indoxyl-tetranitro BT method 总被引:5,自引:0,他引:5
Summary The indoxyl—tetranitro BT method for the demonstration of alkaline phosphatase activity has been optimized and its validity for quantitative histochemistry tested. The study has been performed with model films of polyacrylamide gel incorporating homogenate of rat liver and with cryostat sections from the same livers. Addition of polyvinyl alcohol to the incubation medium greatly improved the localization of the final reaction product in cryostat sections. In polyacrylamide films, the formazan production specifically due to alkaline phosphatase was highest when using a medium containing 100mm Tris-HCl buffer, pH 9.0, 0.2–1.0mm substrate, 0.32mm 1-methoxyphenazine methosulphate, 10mm MgCl2, 5mm sodium azide and 1mm tetranitro BT. For the incubation of cryostat sections in the presence of polyvinyl alcohol, the same medium could be used but the optimum concentrations of substrate and tetranitro BT appeared to be 1–2mm and 5mm respectively. The test minus control reaction was specific for alkaline phosphatase activity and could be inhibited completely with tetramisole. The test minus control reaction was linear with time up to 30 min with model films and up to 15 min with cryostat sections. The formazan production was also linear with the amount of homogenate incorporated in model films and with section thickness up to 18 µm and therefore, the reaction obeyed the Beer—Lambert law. Variation of the substrate concentration yielded aK
M of 0.05mm for aqueous media and aK
M of 0.55mm for polyvinyl alcohol-containing media. The inhibition with tetramisole appeared to be competitive withK
i = 0.07mm for aqueous media andK
i = 0.7mm for polyvinyl alcohol-containing media. These values indicate that the indoxyl—tetranitro BT method is considerably more sensitive than any metal salt or diazonium salt method developed so far. It is concluded that the optimized method described here is a specific, sensitive and valid quantitative histochemical method for the demonstration of alkaline phosphatase activity. 相似文献
6.
Dr. Helen V. Crouse 《Chromosoma》1965,16(4):391-410
Summary Using two reciprocal translocations between chromosomes X and IV in S. coprophila it has been possible to derive two kinds of aneuploid females. Both of the aneuploid complements are detrimental — one is lethal, the other may give rise to viable, fertile adults. Males with aneuploid somatic complements have not been obtained; three different aneuploid complements were tested but gave negative results. Males with euploid soma and aneuploid germ line have been produced in three separate instances; they are viable and fertile.Dedicated to Professor H. Bauer on the occasion of his sixtieth birthday.The studies reported here were supported by grant GB-42 from the National Science Foundation. 相似文献
7.
Physical and mapping properties of distant linkages between genetic markers in transformation of Bacillus subtilis 总被引:8,自引:0,他引:8
M. S. Kelly 《Molecular & general genetics : MGG》1967,99(4):333-349
Summary DNA purified by a procedure based on phenol extraction contained many intact linkages, i.e. between genetic markers showing less than 20% cotransfer. The molecular weight of this DNA, as revealed by zone centrifugation, varied between 4.5×107 and 2.5×108. Linkages with cotransfer frequencies greater than 10% were found to consist of not more than 6.0×107 daltons of DNA, while one linkage showing only 2% cotransfer was provisionally estimated to be about 1.5×108 daltons. With the aim of extending the transformation map of B. subtilis, 16 mutations for nutritional requirements, not suspected—on the basis of the phenotypes involved—to be linked to any other markers, were examined for linkage with each other and to markers on the existing map. Three new pairs of distantly linked markers were found, but no linkage to any location on the known map.The study of the linkage properties of markers which Oishi, Yoshikawa and Sueoka localized on their replication map suggests that some of these markers may have been misplaced. 相似文献
8.
Electrophoretic analysis of the developmental stages and tissues of Anopheles albimanus showed that qualitatively similar allozymes of aconitase (Acon-2) occur at all stages, and the enzyme is widespread in every larval and adult tissues. Relative heat stabilities of the allozymes were investigated by electrophoresis of heated aqueous extracts and by heating the enzyme in situ in acrylamide gels after electrophoretic separation in Tris-citrate and Tris-maleate buffer systems. The pupal aconitase in the crude extract is more stable to heat than the larval and adult enzyme. The presence of citrate ions in the gel increased the stability of aconitase to heat. Studies of substrate specificities indicated that cis-aconitic acid is the best substrate but citric acid can also serve as a substrate. Zymograms developed with isocitric acid as a substrate showed no aconitase electromorphs and produced only isocitrate dehydrogenase bands. Aconitase has a pH optimum of 8.0 and this enzyme is completely inhibited if treated in situ with ethylenediaminetetra-acetic acid (EDTA), p-chloromercuribenzoate (PCMB), and urea at concentrations higher than 5mm, 5×10–5
m, and 2 m, respectively. Acon-2100 and Acon-2105 do not respond differently to the above treatments. Genetic crosses involving a holandric translocation, pericentric inversions, visible mutants, and allozyme markers were analyzed to map the aconitase (Acon-2) locus on the left arm of chromosome 3. The gene sequence (and map distances) on 3L is centromere—esterase-8 (Est-8)—2—esterase-4 (Est-4)—25—esterase-2 (Est-2)—9—Acon-2—5—phosphoglucomutase (Pgm)—7—esterase-6 (Est-6). 相似文献
9.
R. Th. Scholtens 《Antonie van Leeuwenhoek》1950,16(1):245-255
Summary A survey has been given of the results of phage typing of strains ofS. typhi found in Holland. It has been shown, that type A includes a different group of strains in systems drawn up with different Vi phages. An auxiliary system — to be used besides the system ofCraigie andYen — and a few new types, have been described. 相似文献
10.
Genetic control of IgM responses to (T,G)-A — L 总被引:1,自引:1,他引:0
The primary antibody response to aqueous immunization with a low molecular-weight lot of (T,G)-A — L (#420) was studied in congenic pairs of inbred mouse strains. Two new genetic controls were identified, both of which quantitatively regulate the production of IgM anti-(T,G)-A — L antibody. Testing of F1 and F2 progeny demonstrated that one of these genes is linked to the major histocompatibility (H-2) complex, and that high response is dominant over low response. Whether this gene is identical toIr-1A is not yet known. The other gene, designatedIg-TGAL
M
, is linked to the immunoglobulin heavy-chain allotype locus (Ig-1) and is expressed in a genedose dependent manner. Following secondary challenge with (T,G)-A — L 420, quantitative differences in IgG antibody response were observed inIr-1A high-responder congenics differing only at theIg-1 locus. Breeding studies, however, failed to demonstrate any linkage between this locus and the quantitative control of IgG anti-(T,G)-A — L antibody. These data demonstrate thatH-2-linked immune response genes can regulate IgM as well as IgG antibody responses, that genetic control of the IgM response to (T,G)-A — L is linked toIg-1, and that bothH-2-linked andIg-1-linked genes may simultaneously affect an IgM antibody response to the same antigen.Abbreviations used in this paper are (T,G)-A — L
poly-l-(Tyr,Glu)-poly-d,l-Ala-poly-l-Lys
- NMS
normal mouse serum
- SRBC
sheep red blood cells
- i.p.
intraperitoneal
- PBS
phosphate-buffered saline
- RAMG
polyvalent rabbit anti-mouse globulin
- 2-Me
2-Mercaptoethanol
- 2-MeS
2-Me-sensitive
- PFC
plaque-forming cells
- ABC
antigen-binding cells 相似文献
11.
Brian Snoad 《Genetica》1966,37(1):247-254
By appropriate genetical studies using reciprocal translocation stocks it has been possible to confirmLamprecht's evidence that inPisum there are seven linkage groups.
Lamm's evidence for six linkage groups has been shown to be due to incomplete knowledge of the chromosomal structure of certain interchange lines.It is suggested thatLamprecht's system of chromosomal nomenclature should be universally adopted forPisum.Lamm &Miravelle's extended tester set has been accordingly renumbered and the intercrossing of the interchange lines completed in order to extend the confirmatory evidence as to their chromosomal constitution. 相似文献
12.
Summary Five new methods, based upon the selective oxidation of sialic acid residues with 0.4mm periodic acid in approximately 1m hydrochloric acid at 4°C for 1 h (PA*), have been devised for the simultaneous visualization of neutral sugars and either sialic acid and its side chainO-acyl variants orO-sulphate ester. In the first of these, the selective periodate oxidation—borohydride reduction—saponification—selective periodate oxidation—Thionin Schiff—saponification—borohydride reduction—periodic acid—Schiff (PA*—Bh—KOH—PA*—T—KOH—Bh—PAS) technique, sialic acids withO-acyl substituents at C7, C8 or C9 (or which have two of three side chainO-acyl substituents) stain blue while neutral sugars with periodate-sensitivevicinal diols (hexose, 6-deoxyhexose, andN-acetylhexosamine) stain magenta. The second method, the saponification—selective periodate oxidation—Thionin Schiff—saponification—borohydride reduction—periodic acid—Schiff (KOH—PA*—T—KOH—Bh—PAS), stains all sialic acids blue and neutral sugars magenta. In the third procedure, the selective periodate oxidation—Thionin Schiff—borohydride reduction—periodic acid—Schiff—saponification (PA*—T—Bh—PAS—KOH) method, sialic acids without side chain substituents (or which have anO-acyl substituent at C7) stain blue and neutral sugars stain magenta. In the fourth method, the saponification-selective periodate oxidation—borohydride reduction—Alcian Blue pH 1.0—periodic acid—Schiff (KOH—PA*—Bh—AB1.0—PAS) technique,O-sulphate esters stain aquamarine blue and neutral sugars stain magenta. In all of these techniques mixtures of the components stain in various shades of purple. Performance of the KOH—PA*—Bh—AB1.0—PAS technique without the Alcian Blue pH 1.0 step provides a method for the selective identification of neutral sugars in macromolecules that also contain sialic acids. 相似文献
13.
Konrad Bachmann Kenton L. Chambers H. James Price 《Plant Systematics and Evolution》1984,145(3-4):243-258
CrossingMicroseris pygmaea (10 pappus parts) withM. bigelovii (5 pappus parts) results in hybrids with variable pappus part numbers between 5 and 10. Previous work has shown that a system of four additively acting genes determines the average pappus part numbers of these hybrids. In hybrid B87 two genes have a 10-determining and a 5-determining allele each, two others a 5-determining and a null (inactive or missing) allele. Genetic linkage of one of the latter with the enzyme geneEsterase-1 and the leaf shape genespatulate leaves has been demonstrated. Here we demonstrate linkage between one of the two 10-determining genes and the enzyme locusEsterase- Y/B. The genotypes in the pappus part system of many specimens can now be fully determined. This is a major advance for the analysis of the evolution of this additive polygenic system.Genetics of Pappus Part Numbers inMicroseris Hybrid B87, II.—Part I:Bachmann & al. 1981. 相似文献
14.
Large hovering flies with elongated nectar-feeding mouthparts play an important role in the pollination of South African plants. Here we describe and illustrate the pollination of two long-spurred orchids —Disa oreophila
H. Bolus subsp.erecta
Linder andBrownleea macroceras
Sond. — by the long-proboscid flyProsoeca ganglbaueri
Lichtwardt (Nemestrinidae). 相似文献
15.
Electrophoretic variation ascribable to three enzyme loci, coding for a pyruvate kinase (PK1), a glucose phosphate isomerase (GPI1), and an isocitrate dehydrogenase (IDH1), was observed in three species of fish of the genus Xiphophorus. Electrophoretic patterns in F1 hybrid heterozygotes confirmed the dimeric structures of GPI and IDH, and indicated a multimeric structure for pyruvate kinase. Variant alleles at the three loci exhibited normal Mendelian segregation in backcross hybrids. Linkage analyses indicate a gene order and estimated recombination of PK1—10%—GPI1—41%—IDH1. No significant interference or sex- or population-specific recombination difference was detected. This group (designated linkage group IV) was shown to assort independently from the nine loci comprising linkage groups I, II, and III and from 23 other informative markers, within the limits of the data. No conclusions with respect to homology of linkage relationships could be reached, due to the presence of presumably duplicated loci in these fish coding for isozymes whose homology with enzymes in other vertebrate species is as yet unestablished.This work was supported in part by Public Health Service Research Grant CA-28909. 相似文献
16.
Dr. Ute Menge 《Protoplasma》1976,88(2-4):287-303
Zusammenfassung Mehrere Zellentwicklungsstadien der DesmidiaceeMicrasterias denticulata Bréb. wurden mit drei verschiedenen Polysaccharid-Nachweismethoden cytochemisch untersucht. Im Cytoplasma der Grünalge gibt es relativ viele morphologisch gut unterscheidbare Vesikeltypen, die sich mit Hilfe dieser Nachweise — über die morphologischen Unterschiede hinaus — noch stärker differenzieren ließen, auch konnten morphologisch sehr ähnliche Vesikel durch die Färbereaktionen weiter klassifiziert werden. Einige Vesikel wurden auf Grund der cytochemischen und — bereits bekannter — morphologischer Befunde in Beziehung zur Zellwandbildung und Schleimabsonderung der Desmidiacee gebracht.
Die Arbeit wurde im Rahmen eines Forschungsprojektes von Prof. Dr. O.Kiermayer durch die Deutsche Forschungsgemeinschaft unterstützt. 相似文献
Cytochemical studies onMicrasterias denticulata Bréb
Summary Several stages of development of the desmidMicrasterias denticulata Bréb. have been examined with three different methods of polysaccharide cytochemistry. In the cytoplasm of the alga there are relatively many kinds of vesicles which are morphologically discernible and which can be differentiated even more—beyond the morphological distinctions—by means of these techniques. It was also possible to classify morphologically very similar vesicles by the staining reactions. Some of the vesicles were brought into relation to the growth of the cell wall and to secretion of mucilage, because of the cytochemical and—already known—morphological findings.
Die Arbeit wurde im Rahmen eines Forschungsprojektes von Prof. Dr. O.Kiermayer durch die Deutsche Forschungsgemeinschaft unterstützt. 相似文献
17.
Sally Hughes-Schrader 《Chromosoma》1950,3(1):52-65
Summary The sex chromosomes of the male phasmid Isagoras schraderi
Rehn comprise an X and a Y, — each with a submedian kinetochore, and one euchromatic and one heterochromatic arm. At meiosis X and Y form an unequal sex bivalent in which the euchromatic arms are terminally associated. Relatively recent reversion from the XO-XX mechanism characteristic of the Phasmidae is indicated by the presence of the euchromatic arm in both X and Y. The diploid number of the male is 34.Unequal autosomal bivalents are found at meiosis in two other species of Isagoras — Isagoras subaquiles
Rehn and Isagoras sp. — and in Pseudophasma menius
Westwood. The chromosome complements of these species are described. 相似文献
18.
TheOmphalotaceae fam. nov., which include the generaOmphalotus andLampteromyces, are defined on the basis of characteristic sesquiterpenes and of their ability to cause white-rot. Anatomical and morphological features of the representatives of these genera support the creation of this new family. The occurrence of pigments, typical of theBoletales, and of cyanophilous spores, indicate membership of theOmphalotaceae in the orderBoletales. Relationships to the other families of this order — especially to thePaxillaceae — are discussed. The possible functional significance of fungal metabolites is considered.
Herrn Prof. Dr.J. Poelt zur Vollendung seines 60. Lebensjahres gewidmet.—Veränderte Fassung eines Vortrages auf der Tagung der Deutschen Botanischen Gesellschaft, Wien, September 1984. 相似文献
19.
Summary Two recent reports in the literature claim thatl-aspartic acid polymerizes significantly faster thand-aspartic acid in the presence of kaolin in aqueous solution at 90°. The novelty of these observations and their potential significance for molecular evolution and the origin of optical activity in nature has prompted us to attempt a duplication of the experiments involved—using, however, analytical criteria which we felt would be more reliable than those previously employed. In our experimentsl- andd,l-aspartic acid in 0.01M solution were incubated with kaolin at 90° for 8 days. Careful examination of the aqueous residues from such experiments, however, failed to demonstrate any preferential polymerization ofl- overd-aspartic acid under the influence of kaolin, or indeed any significant gross polymerization of aspartic acid at all. 相似文献
20.
K. H. Rechinger 《Plant Systematics and Evolution》1982,141(1):81-84
Saponaria stenopetala sp.n. in Eastern Afghanistan is close toS. pachyphylla
Rech. f. andS. subrosularis
Rech. f.—The nearest allies ofS. makranica sp.n. from Western Pakistan and Southeastern Iran areS. kermanensis
Bornm. andS. floribunda (Kar. & Kir.)Boiss.
Flora Iranicae praecursores 36–37. — Praecursores praecurrentes in Pl. Syst. Evol.139, 313–317 (1982). 相似文献