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1.
Composition of cellular fatty acids was determined for strains of fastidious, Gramnegative, xylem-limited bacteria causing or associated with Pierce's disease of grapevine, phony disease of peach, plum leaf scorch, stunt of ragweed, elm leaf scorch, and periwinkle wilt. The most abundant fatty acids were straight-chain 150, 160, 170, and 180, unsaturated 161, 181, and unsaturated 17-and 19=carbon homologs. Minor fatty acids included straightchain 120, 140, 190, and 200; an unsaturated 15-carbon homolog; hydroxy-substituted 2-OH 120, 3-OH 120, and 3-OH 140; and branched chain iso-140 and iso-200. Cyclopropane acids were not detected. Physiological age had no effect on fatty acid composition. Class analysis of data indicated relative uniformity within the group. Saturated even-carbon chains comprised 31%–42%, unsaturated acids 41%–52%, saturated odd-carbon chains 10%–18%, hydroxysubstituted chains 2%–7%, and branched-chains 1%–4% of total fatty acids. The ratio of saturated-unsaturated acids ranged from 0.8 to 1.2.  相似文献   

2.
Se diferencian 5 arcos de precipitatión en la técnica de inmunoelectroforesis (IEF) luego de enfrentar sueros de 16 pacientes de paracoccidioidomicosis a la paracoccidioidina. El arco l presente en todos los sueros es asimilado a arcos presuntamente específicos descritos previamente. En immunoelectroosmoforesis-inmunodifusión (IEOF-ID) se observaron bandas anódicas y bandas catódicas en todos los casos. La comparación de los resultados obtenidos con las 2 técnicas reveló siempre un mayor número de arcos en IEOF-ID lo que se debería a la aparición de los arcos de localizatión catódica 1 y 2 del inmunoelectroforegrama, tanto en el lado anódico como en el catódico de las láminas de IEOF-ID.
Summary Immunoelectroporesis (IEF) and immunoelectroosmophoresis-immunodiffusion (IEOP-ID) (1) were comparatively used in the diagnosis of 16 patients with mycologically proved paracocidioidomycosis.In IEF, 5 different precipitin arcs were found and identified with arable numbers. Arc. 1, cathodic, present in all the patients, is assimilated to specific arcs previously described by other authors.In IEOP-ID both cathodic and anodic arcs were observed in all the sera.A high number of precipitin arcs were revealed by IEOP-ID technique in comparison to IEF in every case. This should be due to the presence of cathodic arcs 1 and 2 of the immunoelectrophoregram at both sides of the IEOP-ID preparate.
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3.
The effect of carbonnitrogenphosphorus (CNP) ratio of organic substrates on the regeneration of ammonium and phosphate was investigated by growing natural assemblages of freshwater bacteria in mineral media supplemented with the simple organic C, N, and P sources (glucose, asparagine, and sodium glycerophosphate, respectively) to give 25 different substrate CNP ratios. Both ammonium and phosphate were regenerated when CN and NP atomic ratios of organic substrates were 101 and 161, respectively. Only ammonium was regenerated when CN and NP ratios were 101 and 10–201, respectively. On the other hand, neither ammonium nor phosphate was regenerated when CN and NP ratios were 151 and 51, respectively. In no case was phosphate alone regenerated. As bacteria were able to alter widely the CNP ratio of their biomass, the growth yield of bacteria appeared primarily dependent on the substrate carbon concentration, irrespective of a wide variation in the substrate CNP ratio.  相似文献   

4.
Genetics of fertility restoration in hybrid rice   总被引:2,自引:0,他引:2  
Summary The cross combination involving 14 male-sterile lines in rice, when crossed with different maintainers, showed fertility restoration in certain combinations. When F2 segregating populations were classified based on spikelet fertility, fertility restoration was shown to be governed by 31, 9331, and 1231, due to allelic differences. This indicated that the cytosterility of the same group showed monogenic fertility restoration, whereas crossing plants belonging to different cystosterile groups showed a digenic pattern of segregation.  相似文献   

5.
The mechanism for synthesis of monounsaturated fatty acids under aerobic and anaerobic conditions was studied in the facultative anaerobic cyanobacterium, Oscillatoria limnetica. The hexadecenoic acid (C161) of aerobically grown O. limnetica was shown to contain both the 7 (79%) and 9 (21%) isomers, while the octadecenoic (C181) acid was entirely the 9 acid. Incorporation of [2-14C] acetate into the fatty acids under aerobic conditions resulted in synthesis of the 7 and 9 C161 and the 9 C181. Synthesis of unsaturated fatty acids in the presence of DCMU required sulfide. Anaerobic incubations in the presence of DCMU and sulfide (less than 0.003% atmospheric oxygen) resulted in a two-fold increase in monounsaturated fatty acids of both 7 and 9 C161 and 9 and 11 C181. The synthesis of these isomers is characteristic of a bacterialtype, anaerobic pathway.Abbreviations DCMU 3(3,4-dichlorophenyl)-1,1-dimethylurea - MFA monounsaturated fatty acid  相似文献   

6.
A DNA sequence (8–19T) of 2.3 kilobase pairs (kb) of Drosophila melanogaster was localized by in situ hybridization to the extreme ends of polytene chromosomes and to the chromocenter. The relative abundance of this sequence at the ends of polytene chromosomes X2L2R3L3R is 13.41.902.7. This differential distribution is probably due to different copy numbers at the individual telomeric regions. Restriction enzyme analysis of genomic DNA shows that 8–19T sequences are interspersed with other sequences. The clone 8–19T, which contains most of this interspersed repetitive sequence, is itself not internally repetitive but has a complex sequence composition. Some of these sequences are transcribed into poly(A)+RNA. We suggest that the ends of Drosophila chromosomes are of a complex arrangement with some sequences common to all ends.  相似文献   

7.
F. Probst 《Chromosoma》1972,36(3):322-328
Résumé Le dosage du complexe Feulgen-ADN dans des noyaux isolés et étalés sur lames, appartenant à différents taxons du genre Leucanthemum vulgare sensu lato, par voie microspectrophotométrique, permet d'attribuer, avec une certaine réserve, une valeur moyenne en ADN de 0,675 pour le taxon diploïde, de 1,339 pour le taxon tétraploïde et de 1,683 pour le taxon octoploïde, dans un rapport de 1,01,982,5. L'écart par rapport à la valeur théorique est expliqué par l'origine hybride des plantes octoploïdes, ce qui confirme les résultats obtenus par des hybridations et des observations cytologiques antérieures.
Contribution to the taxonomical study of the genus Leucanthemum using cytophotometry
The cytophotometric determination of the relative amount of Feulgen dye-DNA complex in isolated nuclei of Leucanthemum vulgare sensu lato root tips gives the following average values: 0.675 for the diploid taxum, 1.339 for the tetraploid taxum, and 1.683 for the octoploid taxum, fitting a ratio of 1.01.982.5. The deviation from the expected ratio is ascribed to the hybrid allopolyploid origin of the octoploid plants. These results are in agreement with those obtained previously by hybridization and cytotaxonomic studies (Résumé see p. 327).
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8.
Summary The enzymatic synthesis of a peptide compound was carried out successfully in homogeneous organic solvent.Solid Thermolysin was found to catalyze the synthetic reaction of N-benzyloxycarbonyl-L-aspartyl-L-phenylalanine methyl ester (Z-APM; a precursor of sweetner Aspartame) from N-benzyloxycarbonyl-L-aspartic acid (Z-L-Asp) and L-phenylalanine methyl ester (L-PheOMe) in a 98 percent organic medium (ethylacetatebenzenemethanolwater=5029192). The dissolution of enzyme was not observed. The optimal pH shifted to acidic side by 1.0 pH unit, compared with that in aqueous medium. The enzymatic activity of solid thermolysin with an average size of 3.4×9.5 m was determined to be 0.18 moles-product/(mg-solid)·h under the initial concentrations of L-PheOMe of 0.1M and Z-L-Asp of 0.05M, and at pH 6.0 and 40°C.  相似文献   

9.
Summary The simplest possible model of the sex determination process adding autosomal influence to a minimal number of sex chromosomes was developed to explain matings of Tilapia (Sarotherodon) species. Eighteen different genotypes, each having two autosomes (AA, Aa, or aa) and two sex chromosomes (WX, WY, WW, XY, XX or YY) involved in sex determination, are predicted by the theory. Their sex (10 males and 8 females) were determined using a series of directed graphs, showing the relative strength of the chromosome pairs, developed on the basis of Chen's sex ratio results (Chen 1969). This theoretical model predicts eight different sex ratios (01, 13, 35, 11, 97, 53, 31, 10 ); three of them are not predicted by the WXYZ theory. The greatest part of these sex ratios have been obtained experimentally in extensive series of crosses between related species of Tilapia and their hybrids, carried out by several authors. The theory succeeds in explaining all of Chen's results, including those ratios 53 and 01 seen in certain crosses but not predicted by the WXYZ theory. The importance of the autosomes is seen in comparisons of the genotype pairs (AaWY, aaWY), (AaXY, aaXY) and (AAWW, AaWW) in which the first genotype in each case is male while the second is female as proven by the sex ratio results. The members of the pair differ only in the substitution of one autosome for the other. To test the theory, experiments consisting of hormonal sex reversion and a series of crosses are proposed. Finally, theoretical and practical implications of the theory are discussed.  相似文献   

10.
The fatty acid composition of individual myelin lipids from rat forebrain and spinal cord was analysed at 20 and 30 days p.p. During this phase of rapid myelination the proportions of C 160 and C 180 fatty acids decreased whereas the relative amounts of long chain and unsaturated fatty acids increased in most lipid classes. This developmental shift was more pronounced in the forebrain and was different with respect to both magnitude and direction for each myelin lipid. The experimental induction of chronic hyperphenylalaninaemia (hyper-Phe) from day 3 p.p. lead to alterations in the rate of myelination, which were most pronounced in the forebrain. At 20 days, especially in the forebrain, chain elongation and desaturation of fatty acids were delayed. This delay was maximal in sphingomyelin fatty acids, C 180 and C 241. In hydoxycerebrosides, the shift in the fatty acid composition from C 160 to C 220 was accelerated in hyper-Phe rats. No significant difference in the fatty acid composition of any myelin lipid was found in the more mature myelin (spinal cord, 30 days p.p.). No evidence was found of a primary effect of hyper-Phe on myelination.In memoriam of M. Klapproth who died by a tragic accident.  相似文献   

11.
Among 639 spontaneous abortions between the 8th and 14th week of gestation 342 (53.5%) revealed an abnormal karyotype. While the rate of trisomies distinctly increased with advancing maternal age, a decrease in the rate of 45,X conceptuses and polyploidies was observed among abortions from older women. The overall relation of XXXXXXYY among the tetraploidies was 1411 and that of XXXXXYXYY among the triploidies was 26 361. However, when the latter was related to maternal age, a reversal of the XXXXXY ratio of 12 in the younger to 21 in the older age groups became evident. Furthermore a decrease in the rate of paternally derived partial hydatidiform moles was found among the triploid abortion specimens from older women. From these observations we conclude that digyny plays a major role in the origin of triploidy in the increased maternal age groups, while diandry related to immaturity of oocytes and impairment of oocyte cortical function is more frequent in triploid abortions from younger women.  相似文献   

12.
Rice straw, used as a substrate for three successive crops of the fruiting bodies ofPleurotus florida having 22% protein, had less cellulose but more nitrogen and ash than the original straw.In vitro digestibility using bacterial cellulase released 4.3-fold more reducing sugars per g cellulose from spent straw than from plain straw. There was 8-fold increase in biogas production from the spent straw compared with the original when used either in 31 (w/w) or 11 (w/w) combination with cattle dung.
Résumé La paille de riz, utilisée comme substrat pour trois récoltes successives de corps fruités dePleurotus florida, à 22% de protéines, contenait moins de cellulose mais plus d'azote et de cendres que la paille originelle. La digestionin vitro par une cellulase bactérienne, relarguait 4.3 fois plus de sucres réducteurs par g de cellulose à partir de la paille résiduaire qu'à partir de la paille originelle. On observe un accroissement de 8 fois dans la production de biogas à partir de la paille résidualle par rapport à la paille originelle lorsque cellesci sont utilisées en combinaison avec la bouse de vache dans les proportions soit de 31 soit de 11 (p/p).
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13.
Aspects of the induction of diapause were studied in a Dutch strain of the phytoseiid miteAmblyseius potentillae. The photoperiodic response curve was of the long-day type, with a sharply defined critical daylength of 14.5 h. Critical daylength varied only little at temperatures between 15.0 and 22.5°C.All post-embryonic and possibly even late-embryonic stages of development were found to be sensitive to photoperiod; sensitivity appeared to be maximal during the protonymphal stage.It is shown that -carotene is necessary for some early step in the physiological mechanism of photoperiodic induction, and not (or not exclusively) for the expression of the diapause response.Two points of sensitivity to light could be demonstrated in the nights ofld 1311 andld 1212 long-night regimes, using 1-h night interruptions. These results are similar to those obtained in lightbreak experiments with spider mites and insects. However, no effect was found with light interruptions applied during the dark phase of anld 1014 long-night regime.In resonance experiments with a constant photophase (12 h) and a variable scotophase, a weak rhythmic response was found at 22.5°C; at 19.0°C this effect was completely absent.The relative humidity experienced by the mites during diapause induction as well as during diapause development influenced the rate of diapause completion under long days (ld 168). Diapause duration appeared to be shortest when the mites experienced low relative humidity (35±5%) during diapause induction and high relative humidity (75±5%) during diapause termination, and longest under the reverse conditions.  相似文献   

14.
Metabolism of n-6 and n-3 fatty acids in the undifferentiated and differentiated human adenocarcinoma colon cell line (Caco-2) was studied. In cells incubated with either 182n-6 or 183n-3, no significant amounts of long chain n-6 and n-3 metabolites were found. Incubation with either 183n-6 or 184n-3 raised significantly the levels of 203n-6 and 204n-3, respectively. In the undifferentiated cells, significant proportions of 203n-6 and 204n-3 were further 5-desaturated to form 204n-6 and 205n-3, respectively. Incubation with either 204n-6 or 205n-3 raised the levels of their direct elongation products, 224n-6 and 225n-3, respectively. Incubation with 224n-6 or 225n-3 increased the levels of 204n-6 and 205n-6. These results suggest that 6-desaturation in the Caco-2 cells is less active in comparision with elongation, 5-desaturation and retro-conversion. These enzymes were modulated by the state of differentiation, and appeared to be non-specific to n-3 and n-6 fatty acids. When cells were incubated with 183n-6 and 184n-3 concomitantly, the levels of incorporation of total n-6 fatty acids into cellular lipids were greater than those of the n-3 fatty acids, whereas the ratios of 20+22 carbon metabolites to 18-carbon precursor favored n-3 over n-6 fatty acids. These results suggest that n-3 and n-6 fatty acids were not metabolized identically in Caco-2 cells.  相似文献   

15.
Resumen El procedimiento de intercambio iónico empleado en este trabajo ha mostrado ser un método eficiente, sencillo y rápido, para eliminar las fracciones antigénicas aniónicas de un extracto crudo deP. brasiliensis.Su empleo permitió la obtención de un antígeno purificado que contiene algunas de las fracciones catiónicas del extracto crudo. El antígeno responsable de la formación del arco E fue identificado en el extracto purificado, mediante análisis inmunoelectroforético.  相似文献   

16.
The effect of saturated fatty acids from 60 to 160 and oleic acid was determined onLactobacillus leichmannii growing in skim milk. The growth of this strain was markedly inhibited by fatty acids from 80 to 120 but not by straight chain fatty acids greater than 130 or less than 70 and oleate. Laurate was the fatty acid with the highest bactericidal effect. Similar results, with little changes depending on strains, were obtained withL. casei, L. plantarum, L. bulgaricus, L. lactis, L. helveticus. Mutants from theseLactobacillus organisms, resistant to fatty acid inhibition, were isolated by a recycling selection procedure. These mutants exhibited high levels of oxidation for laurate. The presence of 2 mM of this compound in the skim milk culture increased the fatty acid oxidation activity four to ten times higher than was exhibited by the parent strains. The practical implications of these observations are discussed.  相似文献   

17.
The influence of different organic and inorganic nitrogen source combinations and CN ratios was studied in connection with growth and protein production ofBacillus thuringiensis var.israelensis. Protein production was assumed to be proportional to delta-endotoxin production. Delta-endotoxin concentration increased when media were supplemented with (NH4)2SO4, but the delta-endotoxin: biomass dry weight ratio was unaffected by different CN ratios. Organic nitrogen source, yeast extract, could be partially replaced by (NH4)2SO4 with a significant increase in delta-endotoxin production.
Résumé On a étudié l'influence de diverses sources d'azote organique et inorganique et des rapports CN en relation avec la croissance et la production de protéine parBacillus thuringiensis var.israelensis. On fait l'hypothèse que la production de protéines est proportionnelle à la production de delta-endotoxine. La concentration de delta-endotoxine croît quand on ajoute au milieu du (NH4)2SO4, mais le rapport delta-endotoxine: poids sec de biomasse n'est pas affecté par différents rapports CN. On peut remplacer partiellement la source organique d'azote, l'extrait de levure, par du (NH4)2SO4 avec une augmentation significative de production de delta-endotoxine.
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18.
Hematocrit levels in highland (3900–4500 m) AKODON (4 species) showed no change following a month at sea level, but showed a reduction of about 50 ml/1 after an additional 1–2 months. Feral MUS established at 4500 m had more cells(570 vs.470 ml/l) than those from sea level; about half this advantage was lost after a week at sea level. Highland species or races showed no consistent advantage in erythrocyte level over lowland species. The lowland PHYLLOTIS DARWINII LIMATUS actually had a higher hematocrit than any of the highland PHYLLOTIS. Mean cell hemoglobin concentrations ranged from 28 to 33 g/100 ml in rodents, and to 42 g/100 ml in the alpaca.Mean cell volumes ranged from 44 to 65 3 in rodents, and were 25–263 for the alpaca and vicna. The cell hemoglobin mass varied from 13 to 18 g in rodents and was 11.5g in the alpaca and vicuña. None of these values for rodents appear remarkable.
Zusammenfassung Die HÄmatokrit-Werte von 4 Arten Hochland-AKODON (3900–4500 m) zeigten nach einem Monat Aufenthalt der Tiere auf Meereshöhe keine VerÄnderung; nach 2–3 Monaten waren die Werte 50 ml/l niedriger als der Vorwert. Wilde MUS in 4500 m Höhe hatten 570 ml und wilde MUS auf Meereshöhe 470 ml Erythrozyten/1 Blut. Wurden die Tiere aus der Höhe ins Tal gebracht, verschwand die HÄlfte des Unterschiedes innerhalb einer Woche. Die Erythrozyten-Werte von Hochland-Arten und -Rassen zeigten keine übereinstimmende überlegenheit über die von Tiefland-Arten. Tiefland PHYLLOTIS DARWINII LIMATUS hatten sogar einen höheren HÄmatokrit als Hochland PHYLLOTIS. In Hochland-Nagern betrug der mittlere Zell-HÄmoglobingehalt 28 bis 33 g/100 ml, in Alpaca bis 42 g/100 ml. Das mittlere Zellvolumen war bei Nagern 44–653 und beim Alpaca und Vivuna 25–263. Die Menge HÄmoglobin pro Zelle betrug 13–18g bei Nagern und 11-5g beim Alpaca und Vicuna. Die Werte bei Nagern im Hochland sind in keiner Weise bemerkenswert.

Résumé Les valeurs hématocrites de 4 sortes d'AKODON de hautes terres (3000 – 4500 m) ne montraient pas de changement après un mois de séjour des animaux au niveau de la mer; après 2–3 mois, les valeurs étaient 50 ml/l plus basses que la valeur précédante. A 4500 m d'altitude les MUS sauvages avaient 570 ml érythrocytes/l sang et au niveau de la mer 470 ml. Les animaux transportés de l'altitude dans la vallée, la moitié de la différence disparut au bout d'une semaine.Les valeurs d'erythrocytes de sortes et rasses de hautes terres ne montraient point de supériorité concordante aux sortes de basses terres. PHYLLOTIS DARWINI LIMATUS de basses terres avaient mÊme un hématocrit plus haut que le PHYLLOTIS de hautes terres. Le contenu moyen de l'hémoglobine cellulaire des rongeurs de hautes terres était de 28 à 33/100 ml,chez Alpaca jusqu'à 429/100 ml. Aux rongeurs, la volume cellulaire moyenne,était 44–653et Alpaca et Vicuna avaient 25–263. Les rongeurs avaient une quantité d'hémoglobine par cellule de 13–18g, les Alpaca et Vicuna avaient 11,5g. Les valeurs aux rongeurs ne sont remarquable en aucun égard.
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19.
The experimental data on the absorption of plane polarized light by a solution of cattle rhodopsin at –196 C have been theoretically analysed to model the directional absorption properties of rhodopsin and prelumirhodopsin. It has been found that rhodopsin and prelumirhodopsin are planar absorbers having ratios of about 1007 and 1004, respectively, between the extinction coefficients along the long axis and perpendicular to it. These results support that the chromophore in prelumirhodopsin is more linear than the chromophore in rhodopsin.Work partially supported by Department of Science and Technology (India)Associated with the Biochemistry Cell  相似文献   

20.
Zusammenfassung Das Fettsäurespektrum von männlichen Flußkrebsen Orconectes limosus wurde gaschromatographisch analysiert. Die Fettsäuren zeigen eine spezifische Verteilung auf die Lipidklassen. Das Gesamtspektrum entspricht dem Schema eines Süßwassertieres im Winter mit den größten Fraktionen: C160, C181, C202 und C204 (zusammen rund 53% der Gesamtfettsäuren). In verschiedenen Fraktionen wurden ungeradzahlige und verzweigte Fettsäuren gefunden.Durch Verfüttern von Kartoffeln und Lebertran kann das Spektrum beeinflußt werden. Die Fettsäuren in der Mitteldarmdrüse, und in weniger starkem Ausmaß im Restkörper, haben sich nach viermonatiger Fütterung mit Lebertran qualitativ und quantitativ dessen Spektrum angepaßt. Nach siebenmonatiger Fütterung mit Kartoffeln zeigen Mitteldarmdrüse und Restkörper ein Spektrum, das dem eines unbehandelten Kontrollkrebses ähnelt und sowohl C182 als auch höher ungesättigte Fettsäuren enthält. Hierfür kommen zwei Deutungen in Frage: Entweder wird das Spektrum der Fettsäuren in Strukturlipiden aufrechterhalten, oder es erfolgt de novo Synthese einer C18:26,9-Fettsäure und deren Verlängerung analog dem von Wirbeltieren bekannten Weg.
The fatty acid composition in the crayfish, orconectes limosus, and the effect of nutrition
Summary The fatty acid composition in the male crayfish, Orconectes limosus, was analysed by gas-liquid chromatography. The fatty acids were found to have a specific distribution in different lipid classes. The composition corresponds to those of a fresh water animal in winter with the most important acids: C160, C181, C202, C204 (including about 53% of the total acids). In several lipid classes oddnumbered and branched chain fatty acids could be detected.Potatoe and fish-liver oil diets influence the fatty acid composition. After four months feeding with fish-liver oil the fatty acids in the hepatopancreas and to a lesser extent in the rest body show a similar spectrum as the fed oil. After feeding for seven months with potatoes hepatopancreas and rest body exhibit a fatty acid composition representative for the untreated animal, which contains C182 as well as higher unsaturated acids. These findings support the hypotheses that either the fatty acid composition in the structure lipids was maintained or that a C1826,9-fatty acid was de novo synthesized and elongated analogous to the known vertebrate pathway.


Herrn Prof. Dr. K. Urich bin ich für die Anregung zu der vorliegenden Arbeit und für die Durchsicht des Manuskriptes zu großem Dank verpflichtet.  相似文献   

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