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1.
A new species ofPenicillium belonging to theP.funiculosum series of the Biverticillata — Symmetrica section is described from the rhizosphere ofBrassica campestris var.toria. The species is characterized by the presence of penicilli with 8–12 metulae on malt-extract agar and a very limited sporulation on Czapek-Dox agar. The species is namedPenicillium korosum on account of its broom-like penicilli.The authors are grateful to Prof. Kenneth B. Raper, Dr. Amelia Stolk and Dr. D. B. Prest for valuable comments, to Rev. Fr. Prof. Dr. Santapau and Fr. Ignatius Menezes for latinizing the specific diagnosis and to the Council of Scientific and Industrial Research, India, for financial assistance. 相似文献
2.
HÅKAN ÅBERG 《Physiologia plantarum》1978,44(3):224-230
Branches of Vaucheria dichotoma (L.) Ag. were induced in two ways: by cutting, which led to a branch in the wound area and by exposure to light. Blue and red light were most active in branch formation. The light intensity dependence and the action spectrum of branch formation showed patterns similar to those of photosynthesis. Photosynthetic involvement was also indicated by the DCMU inhibition of branch formation. Elongation-branching studies at different photoperiods showed that branching was increased by the presence of more photosynthetic light than was necessary for elongation. It may be concluded that photosynthesis exerted the main control of the branch formation of V. dichotoma. However, the action spectrum of branch formation showed a higher efficiency in blue light than would be expected from the action spectrum of photosynthesis. It is therefore possible that apart from the main induction via the photosynthetic pigments, other blue light sensitive pigments may have a regulatory effect. Far-red light treatment of filaments pre-exposed to 8-h and 16-h light periods did not affect branch formation. Spectrophotometrical detection of phytochrome was not successful. This may indicate that there is no participation of phytochrome in branch formation. I am indebted to Dr. Lisbeth Fries for her interest. I also wish to thank Prof. Lars Olof Björn and his friendly staff at the Institute of Plant Physiology at the University of Lund, where some of the experiments were carried out. I am grateful to AB Tomaso Minori for revising the English test and to Miss Inga-Britt Jansson for typing it. The investigation was supported financially by a grant to Dr. Lisbeth Fries from the Swedish National Science Research Council. 相似文献
3.
Summary To identify the monoamine (s) produced in the paraventricular organ (PVO) and the nucleus infundibularis dorsalis (NID) of Xenopus laevis tadpoles, formaldehyde-induced fluorescence in these hypothalamic structures was analysed by microspectrofluorometric techniques. Reference values were obtained by recording excitation and emission spectra of fluorescence in monoamine containing protein models. The maxima of the excitation and emission spectra, both under normal conditions and after treatment with HCl vapour, indicate the presence of dopamine. Based on a number of emission spectra, the PVO and NID might also contain serotonin. With regard to the functional significance of dopamine produced in the hypothalamic nuclei, it may be concluded that the catecholamine is probably identical with the melanotropin inhibiting factor (MIF).The authors wish to thank Prof. Dr. P.G.W.J. van Oordt for his stimulating interest and support. The skillful assistance and valuable contributions of Miss A. G. Fennema and Miss M.G.A. de Bruyn are gratefully acknowledged. Many thanks are due to Prof. Dr. A. Oksche for the opportunity of performing measurements on fluorescence, during a visit to his institute (Zentrum für Anatomie und Cytobiologie, Gießen, BRD). The measurements were carried out by Dr. H.-G. Hartwig, whose help and advice are highly appreciated. 相似文献
4.
Summary In the fundus striati of the cat a few multiple ciliated astroglial cells and a single-ciliated small neuron were observed. In astrocytes cilia display a 9+2 subfiber configuration.
Acknowledgement. The authors are grateful to Prof. Dr. R. Hassler for his encouragement and valuable discussions 相似文献
5.
Two chloroplast envelope proteins from spinach (Spinacia oleracea L.) exhibiting relative molecular masses (Mrs) of 26 and 14 kDa are apparently phosphorylated by a unique Ca2+-dependent serine protein kinase. The activity of this enzyme shows the same sensitivity towards pH, Ca2+, Mg2+, H7 [1-(5-isoquinolinesulphonyl)-2-methylpiperazine] and ATP concentrations (Siegenthaler and Bovet 1993, Planta 190, 231–240). Autoradiographic analyses following two-dimensional-gel electrophoresis (isoelectric focusing and SDS-PAGE) associated with Western blotting experiments indicate that these two phosphoproteins appeared to be pools of the light-harvesting complex of photosystem II (LHCII) and of the ribulose-1,5-bisphosphate carboxylase-oxygenase (Rubisco) small subunit, respectively. Immunoprecipitation of envelope-phosphorylated proteins, using immunoglobulins (IgG) directed to the apoprotein of LHCII and to the holoenzyme of Rubisco confirmed that LHCII and the Rubisco small subunit effectively incorporated 32P from (-32P)ATP in isolated envelope membranes. We propose that, in agreement with the fact that protein import is driven by ATP, the phosphorylation of LHCII and the Rubisco small subunit could take place after the processing of precursor proteins and could be an obligatory step for their internalization into chloroplasts.Abbreviations 2D
two dimensional
- IEF
isoelectric focusing
- IgG
immunoglobulin G
- LHCII
light-harvesting chlorophyll a/b proteins of PSII
- LHCII A
apoprotein a of LHCII
- LHCIIB
apoprotein b of LHCII
- LS
Rubisco large subunit
- Mops
(3-[N-morpholino]propanesulfonic acid)
- Mr
relative molecular mass
- PI
isoelectric point
- Rubisco
ribulose-1,5-bisphosphate carboxylase-oxygenase
- SS
Rubisco small subunit
The authors are grateful to Delphine Herrmann and Xavier Denys for their technical assistance. They also greatly thank Prof. R. J. Ellis and Dr. L. Barnett (Warwick University, UK) and Dr. P. Schürmann (University of Neuchâtel, Switzerland) for providing them with antibodies directed to the pea and spinach Rubisco holoenzymes and Dr. M. Spangfort (Lund University, Sweden) for his gift of the antibody directed to the pea LHCII apoprotein. This study was supported by the Swiss National Science Foundation. This work was part of a doctoral program carried out by L.B. in the Laboratoire de Physiologie végétale, Université de Neuchâtel, Switzerland. 相似文献
6.
Zusammenfassung 67 Proben von 5Pertusaria-Arten, deren Thallus C+ rot Reaktion zeigt, wurden dünnschicht- und papierchromatographisch geprüft.P. hemisphaerica undP. velata (beide mit Lecanorsäure) sowieP. bryontha undP. subviridis (beide mit Gyrophorsäure) wurden erstmals chemisch untersucht. InP. lactea wurde das Vorkommen von Lecanorsäure und Variolarsäure bestätigt. 2 Proben, die nur alsP. lactea bestimmt werden können, jedoch dem Typ nicht entsprechen, enthielten zusätzlich Spuren Psoromsäure. Weiterhin wurden 5 Proben vonP. rupestris (C-)geprüft (mit Stictinsäure und dem Xanthon Coronaton).Beide Autoren: 1 Berlin 41, Grunewaldstr. 35.Für die Entleihung von Herbarmaterial danken wir den Herren Prof. Dr. G.Follmann (B), Prof. Dr. H.Merxmüllee (M), Prof. Dr. J.Poelt (Berlin) und Dipl.-Ing. H.Ullrich (Goslar), für die Überprüfung einiger Proben Herrn Dr. O.Almborn (Lund). Für die Überlassung von Testsubstanzen sind wir den Herren Prof. Dr. G.Follmann (B), Dr. habil. S.Huneck (Freital) und Frau Dr. C. F.Culberson (Durham, N. C.) zu Dank verpflichtet. — Herrn Prof. Dr. J.Poelt danken wir sehr für die Anregung der Arbeit und die ständige Beratung bei der Durchführung. 相似文献
7.
Summary The cycle of synaptic vesicles was studied in isolated nerve terminals and in the electric tissue of Torpedo marmorata. The synaptosomes, as used in this investigation, were a pure cholinergic subcellular fraction that captured dextran particles as an extracellular marker. This endocytotic phenomenon was enhanced by potassium depolarization. Field electrical stimulation (1 Hz and 10 Hz) of the electric organ induced the appearance of membrane foldings into presynaptic terminals. Morphometric studies showed that the number of synaptic vesicles did not decline until after at least 30 min. On the other hand, at 10 Hz these changes were accompanied by an increase in length of the membrane of the terminal. At 15 min of recovery after prolonged stimulation, there was a great increase in density of synaptic vesicles with a large number of vesicles of small diameter. This increase was accompanied by a decrease of membrane length, suggesting that reformation of vesicles is related to retrieval of membrane. Pharmacological stimulation with ouabain produced changes similar to those of long-term electrical stimulation. These changes in membrane were accompanied by a decrease of the population of synaptic vesicles and a wide variation in their diameters. It is concluded that structural changes reported here could not be correlated with kinetics of the transmitter release.We are grateful to Dr. E. Cañadas, Prof. Dr. D. Ribas and Dr. J. Tomás for valuable help and encouragement. We are indebted to Dr. P. Arté and to the staff of the Acuario de Barcelona del Instituto de Investigaciones Pesqueras for providing specimens of Torpedo marmorata. This investigation was supported by a grant Formación Personal Investigador del Ministerio de Universidades e Investigación 相似文献
8.
D. M. Elgersma A. C. M. Weijman H. J. Roeymans G. W. van Eijk 《Journal of Phytopathology》1984,109(3):237-240
Falcarinol and falcarindiol were isolated from tomato vascular tissue infected with Verticillium albo-atrum and identified. Separation and characterization of trimethylsilyl derivatives of four tomato phytoalexins could be obtained by capillary gas chromatographymass spectrometry. We are most grateful to Dr. P. J. G. M. de Wit , Agricultural University, Wageningen, to Dr. D. T. Coxon , Food Research Institute, Norwich and to Dr. M. S. Kemp , Long Ashton Research Station, Bristol for making their analytical data available for us. Also thanks are due to Miss J. I. Liem , Mr. G. Verweij and C. Loriaux for their assistance. 相似文献
9.
In a permanent plot experiment started in 1971, the effects of several management regimes on diversity of a Dutch chalk grassland have been investigated and the results have been compared to existing models predicting general trends in diversity. Treatments included grazing, mowing, and leaving untouched; in the mown plots, the effects of fertilizing and sod cutting were also studied. Grazing resulted in the highest diversity, leaving untouched in the lowest (ca. 42 and 15 spp. per m2, respectively). Within the mown plots, fertilizing decreased diversity. The effects of sod cutting disappeared after some years. The results conform best with the response surface model of Huston (1979) relating diversity to frequency of population reduction and rate of competitive displacement, but a slight modification of the shape of the surface is suggested.Nomenclature follows van der Meijden et al., 1983.The authors are very grateful to Dr J. Miles (Banchory, U.K.) for stimulating remarks and to Prof. Dr. M. J. A. Werger, Dr R. K. Peet and two reviewers for many valuable comments and suggestions. 相似文献
10.
J. Duty 《Plant Ecology》1985,59(1-3):177-184
Studies of the beeches and beech woods of eastern central Europe revealed, that in the postglacial period not only Fagus sylvatica (L.) emend. reimmigrated from the refugial territories in the SE-as has generally been accepted, but also the transitional taxa, which originated from hybrids with F. orientalis Lipsky. The NW area limit of these intermediate taxa must be revised. The presence in central Europe of these taxa-which form own Fagion alliances and associations in the SE (Fagus intermedia ssp. moesiaca and ssp. taurica) as well as the presence of other southeastern species in central European beach woods shows, that their postglacial development is parallel to, but different from other areas. The taxon Fagus intermedia (ssp. neglecta and ssp. transitus) became differential taxa of a central European region of the Fagion medioeuropaeum. Plant sociologists are therefore requested to make new and critical analyses of the beech woods in Europe, with special attention to the Fagus taxa, in order to establish in detail the geographical distribution and phytosociological significance of Fagus intermedia.The author offers to determine or revise Fagus material (herbarium collections).
Danksagung. Ich möchte meinen tiefsten und allzeitigen Dank besonders den Herren Prof. Dr. A. O. Horvat (Pécs), Prof. Dr. Ch. Moulopoulos, Prof. Dr. B. Jovanovié, Prof. Dr. I. Dumitriu-Tataranu, Prof. Dr. R. Bornkamm, Prof. Dr. M. A. Kotschkin, Prof. Dr. P. Fukarek, Prof. Dr. K. Browicz für gewährte Unterstützung aussprechen und ganz besonders unserem unvergeßlichen verstorbenen Prof. Dr. Drs. h.c. R. Tüxen, der mir zur Fortführung dieser Studien Mut machte. 相似文献
11.
Summary For the study of the hypothalamo-hypophysial system of Xenopus laevis tadpoles, hypothalamic lesions were made by means of the electrocoagulation technique. Lesioning of the ventral region of the preoptic nucleus resulted in a decrease of the number of ACTH cells in the pars distalis of the pituitary gland and in a diminution of the PAS-positive reaction of these cells. In addition, regeneration of the neurosecretory cells of the ventral region of the preoptic nucleus observed 6 weeks after lesioning was accompanied by the reappearance of normal PAS-positive ACTH cells in the pars distalis. It is suggested that the neurosecretory cells of the ventral region of the preoptic nucleus of Xenopus laevis tadpoles are related to the ACTH synthesizing cells, probably by producing CRF.Dedicated to Prof. Dr. med. W. Bargmann on the occasion of his 70th birthdayThe authors thank Prof. Dr. J.C. van de Kamer for his interest, Prof. Dr. P.G.W.J. van Oordt for his many helpful comments, and Messrs. H. van Kooten, E. van der Vlist, J.J. van der Vlis and M.C.A. van Pinxteren for preparing the illustrations 相似文献
12.
We have subjected peas (Pisum sativum L.) to four different oxidative stresses: cold conditions (4 °C) in conjunction with light, treatment with paraquat, fumigation with ozone, and illumination of etiolated seedlings (greening). In crude extracts of leaves from stressed plants, an increase (up to twofold) in activity of glutathione reductase (GR) was observed which was consistent with previous reports from several laboratories. In all cases, except for ozone fumigation, the increase in activity was not due to an elevation in the steady-state levels of GR protein. None of the applied stresses had any effect on steady-state levels of GR mRNA. In contrast to the small increase in GR activity, the K
m of GR for glutathione disulphide showed a marked decrease when determined for extracts of stressed leaves, compared with that from unstressed plants. This indicates that GR from stressed plants has an increased affinity for glutathione disulphide. The profile of GR activity bands fractionated on non-denaturing acrylamide gels varied for extracts from differently stressed leaves and when compared with GR from unstressed plants. The changes in GR-band profiles and the alteration in the kinetic properties are best explained as changes in the isoform population of pea GR in response to stress.Abbreviations GR
glutathione reductase
- GSSG
glutathione disulphide
- Rubisco
Ribulose-1,5-bisphosphate carboxylase-oxygenase
- RNase A/T1
ribonucleases A and T1
We are grateful to Prof. Alan Wellburn and Dr. Phil Beckett (Division of Biological Sciences, University of Lancaster, UK) for providing ozone-fumigated material and Dr. Jeremy Harbinson for providing material grown at 4° C. This work was supported by a grant-in-aid to the John Innes Institute from the Agricultural and Food Research Council. E.A.E. and C.E. gratefully acknowledge the support of a John Innes Foundation studentship and a European Molecular Biology Organisation Fellowship respectively. 相似文献
13.
14.
E. P. Eleftheriou 《Planta》1994,193(2):266-274
The structural aberrations of the cell walls of protophloem sieve elements (PSEs) in roots of wheat (Triticum aestivum L. cv. Maris Huntsman) caused by the anti-microtubule drug colchicine were investigated by electron microscopy. The initial effect of the drug on cell wall development was found to be an exceptionally rough wall surface, presumably caused by an uncontrolled fusion of Golgi vesicles with the plasma membrane. Cellulose microfibrils, which in normal PSEs are aligned transversely to the long axis and parallel to the cortical microtubules, in colchicine-treated PSEs display a predominant longitudinal orientation. The pattern of wall development is disturbed by deposition of wall material also within the sieve pores of the sieve-pore/plasmodesmata complexes, resulting in evenly thickened walls instead of the normal uneven layers, and in narrowing the sieve pores to the size of plasmodesmata. In prolonged and continuous colchicine treatment, PSEs develop unusual wall ingrowths projecting deeply into the cytoplasm, creating an extraordinary cell type not found in normal roots. The results confirm the view of microtubule involvement in the proper deposition and orientation of cellulose microfibrils, and in the normal patterning of the cell wall thickenings of differentiating PSEs.Abbreviations c
colchicine-treated
- PSE
protophloem sieve element
The author is grateful to Dr. B. Galatis, Dr. P. Apostolakos and Dr. C. Katsaros, Institute of General Botany, University of Athens, Greece, for helpful discussions and suggestions, and for the generous gift of the colchicine used here. This work was carried out in the Department of Botany, University of Thessaloniki, Greece, while observations were also made in the Lehrstuhl für Zellenlehre, University of Heidelberg, Germany, and in the Department of Botany, University of Georgia, USA. The author is thankful to Prof. E. Schnepf (Zellenlehre, Heidelberg, Germany) and Prof. B.A. Palevitz (Department of Botany, University of Athens, Ga., USA), for generously providing access to their equipment and facilities. The work was financially supported in part by the Stiftung Volkswagenwerk and by the Research Committee, University of Thessaloniki (No 7537). 相似文献
15.
《Plant biology (Stuttgart, Germany)》1967,80(6):331-338
Se describe una forma de vida de cactáceas semicrípticas (fig. 3) del norte de Chile. Su distribución se extiende entre Antofagasta y Coquimbo (fig. 1) y se encuentra ligada a la presencia de neblinas costeras (camanchaca). Se enumeran las principales especies que tienen esta forma de vidi semicríptica. Se discuten, tomando como ej. Neochilenia napina (Phil.) Backbg., algunas de sus características morfológicas (p. ej. radicación) e histológicas en relación a los factores ambientales. Estos condicionan en gran parte esta forma de vida, pues en cultivo estas plantas pierden su fisonomía original, emergiendo del suelo (fig. 5). Herrn Prof. Dr. G. Hoecker , Dekan der Facultad de Ciencias, Universidad de Chile, sei hier besonders für seine Unterstützung bei der Ausführung dieser Arbeit gedankt. Für freundliche Hilfe und Ratschläge möchte ich auch Herrn Dr. A. Kohler (Freising-Weihenstephan), Herrn H. Lembcke , Frau Professor F. Sudzuki und Herrn Prof. F. Schlegel (letztere von Santiago, Chile) danken. 相似文献
16.
17.
Ohne Zusammenfassung
Mit 2 Abbildungen
Aus dem Hauptlaboratorium des Stadtkrankenhauses, 7033 Leipzig, Friesenstr. 8 (Direktor: Prof. Dr. med. habil.D. Lohmann)
Herrn Prof. Dr. Dr. Dr. h.c. Dr. h.c.E. Strack zum 70. Geburtstag in Dankbarkeit. 相似文献
18.
C. D. Notenboom 《Cell and tissue research》1972,134(3):383-402
Summary The development of the preoptic nucleus of Xenopus laevis tadpoles during metamorphosis was studied and the effect of osmotic stimulation on this process investigated. The development of this region was not affected by treatment for one or more days in hypertonic media. It was found that at the end of metamorphosis the neurosecretory cells in the preoptic nucleus are localized in three regions: the rostro-dorsal, the caudo-dorsal and the ventral region. After osmotic stimulation only the neurosecretory cells of the caudo-dorsal region appeared to have reacted, as indicated by their loss of neurosecretory (PIC positive) material. It is concluded that the cells of this region may be involved in the synthesis of the posterior lobe hormones.The author thanks Prof. Dr. J. C. van de Kamer and Dr. F. C. G. van de Veerdonk for their interest and many helpful discussions, Dr. L. Boomgaart and Dr. A. P. van Overbeeke for correcting the English text and Miss C. M. G. van Bemmel for technical assistance. 相似文献
19.
Chizuka Ide 《Cell and tissue research》1972,131(2):171-186
Summary The origin of the melanosome in the pigment epithelium of the chick embryo was studied by electron microscopy and cytochemistry of tyrosinase. The melanosome appears first at stage 16 in the dorso-caudal region of the optic cup and the first appearance of the tyrosinase activity can also be detected at the same stage in Golgi sac. At the early stages, premelanosomes and amorphous, electron dense granules which are considered to be the developing premelanosomes appear as a group at the basal region of the outer layer cell. The membrane of these granules is connected with that of ER. Attention should be paid to the fact that there are tyrosinase-negative premelanosomes, even when Golgi sac and Golgi vesicles are tyrosinase-positive. According to these facts it can be said that the site of origin of premelanosomes are not Golgi vesicles, but the smooth-surfaced ER connected with the rough-surfaced ER, and that the tyrosinase is transported to premelanosomes by tyrosinase-containing vesicles which originate from matured Golgi sac.The author is grateful to Prof. Dr. Junnosuke Nakai for his encouragement and valuable suggestions. Thanks are also due to Prof. Dr. Eichi Yamada and Prof. Dr. Shiro Igarashi for their comments on the electron-microscopic study. 相似文献