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1.
Ohne Zusammenfassung
Gregory, R .P . Experiments withPrimula sinensis
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2.
H. D. Krausch 《Plant Ecology》1985,59(1-3):193-198
Aquatic macrophytes with oceanic and suboceanic distribution occur in the G.D.R. mainly in Littorelletea, Isoeto-Nanojuncetea and Montio-Cardaminetea communities. Within the Potametea they are almost entirely confined to the Ranunculetum fluitantis and to the group of Batrachium communities within the Nymphaeion. Within the territory of the G.D.R. several of these species are reaching the eastern border of their distribution areas. Nearly all of them are more or less endangered or even threatened by extinction.
Die Sippennomenklatur richtet sich nach Casper & Krausch (1981, 1982).  相似文献   

3.
Ohne Zusammenfassung
Gregory, R. P. On gametic coupling and repulsion inPrimula sinensis
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4.
The time-evolution of germination of oat seeds, suspended in the standard 5mm N. M. R. tube and supplied by water, was investigated continuouslyin vivo by the pulsed N. M. R. of water protons at the level of the seed. The results show that the spin- lattice relaxation time T1 yield the physiological information: in the germinated (living) seeds, the T1’s are higher than in the killed seeds.   相似文献   

5.
Ohne Zusammenfassung
Salaman, R.N. Heredity and the Jew
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6.
Ohne Zusammenfassung
A Monograph of the Jacamars and Puffbirds or familiesGalbulidae andBucconidae by P. L. Sclater. Gr. 4 to. London. Published for the author by R. H. Porter 6 Tenterden Street and Dulau & Co. Soho Square. 171 Seiten und 55 Kupfertafeln
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7.
Abstract The polymerase chain reaction?restriction fragment length polymorphism technique (PCR?RFLP) was used to compare Rhodnius domesticus (Neiva & Pinto), R. pictipes (Stal), R. prolixus (Stal) and R. stali (Lent, Jurberg & Galvão) (Hemiptera: Reduviidae). The enzyme BstUI differentiated R. domesticus, R. pictipes and R. prolixus, and HhaI differentiated R. domesticus, R. pictipes and R. stali. With the fingerprinting analysis generated by these two enzymes, it was possible to clearly identify all four species in the study.  相似文献   

8.
With 600 species Ranunculus is the largest genus in Ranunculaceae, and has a broad global distribution. We studied the karyotypes of R. constantinopolitanus and R. sericeus species of Ranunculaceae and identified their symmetry level. New chromosome numbers of 2n = 21 (Nodeh woods population) and 2n ca. 63 (Javaherdeh population) are reported for R. constantinopolitanus. Two different populations of R. sericeus had two different chromosome results. We investigated morphological and karyological studies along with pollens micromorphology. Different populations of R. constantinopolitanus and R. sericeus, with different chromosome numbers showed morphological and micromorphological differences. Therefore, we considered the two populations of R. sericeus as cytotypes. There was a correlation between the studied morphological characters and pollen size with ploidy levels in the two R. constantinopolitanus populations.  相似文献   

9.
The genomic constitutions of Roegneria alashanica, R. elytrigioides, R. magnicaespes and R. grandis were studied using GISH. DNA of Pseudoroegneria spicata (St), P. libanotica (St), P. stipifolia (St), R. ciliaris (StY), Lopophyllum elongatum (Ee), Agropyron cristatum (P) and Hordeum bogdanii (H) were used for probing, respectively. The results indicated that: 1) R. alashanica and R. magnicaespes contained one St genome, the other genome was unidentified, however, it was not an E, P, H or Y genome; 2) R. elytrigioides contained two St genomes and should on this basis be included in Pseudoroegneria; 3) R. grandis contained an St and an Stg genome. The Stg genome is suggested to be a modified form of the St genome of Pseudoroegneria and to be homoeologous with the Y genome. It might be an intermediate type between the St and Y genomes. Therefore, R. elytrigioides should be treated as Pseudoroegneriaelytrigioides.Roegneria alashanica, R. magnicaespes and R. grandis does apparently not belong in the genus Roegneria but further studies are needed to establish their correct taxonomic position.  相似文献   

10.
A neotype specimen is designated for R. formosa and a representative specimen for R. sanguined, thus securing taxonomic concepts for these names. Two very similar taxa are proposed as new: R. eosanguinea, which differs from R. sanguinea chiefly in exhibiting clamp connections, and R. neoformosa which differs from R. formosa chiefly in the absence of clamps. The subject of mimic taxa is briefly discussed.  相似文献   

11.
Rhizobium tropici, R. leguminosarum bv phaseoli and R. loti each have an active C4-dicarboxylic acid transport system dependent on an energized membrane. Free thiol groups are probably involved at the active site. Since EDTA inhibited succinate transport in R. leguminosarum bv phaseoli and R. loti, divalent cations may participate in the process; the activity was reconstituted by the addition of Ca2+ or Mg2+. However, EDTA had no effect on succinate transport in R. tropici, R. meliloti or R. trifolii strains. Ca2+ or Mg2+ had a similar effect on the growth rates of R. tropici and R. leguminosarum bv phaseoli; R. tropici did not require Ca2+ to grow on minimal medium supplemented with succinate but R. leguminosarum bv phaseoli required either or both of the divalent cations Ca2+ and Mg2+. A R. tropici Mu-dI (lacZ) mutant defective in dicarboxylic acid transport, was isolated and found unable to form effective bean nodules.The authors are with the Division of Biochemistry, Instituto de Investigaciones Biológicas Clemente Estable, Avda, Italia 3318, 11.600 Montevideo, Uruguay  相似文献   

12.
Morphological and cytological investigations as well as crossing experiments were carried out withRanunculus seguieri Vill. and 4 species of theRanunculus alpestris L. group (R. alpestris L.,R. traunfellneri Hoppe,R. bilobus Bertol.,R. crenatus Waldst. & Kit.). ForR. seguieri andR. alpestris, localities and distribution are given in addition to extensive diagnoses. A key to the species includes morphological characteristics and distribution data forR. traunfellneri, R. bilobus, andR. crenatus. New diagnostic characters are described. Crossing experiments betweenR. seguieri and the species of theR. alpestris group were unsuccessful. All 5 species have a chromosome number of 2n = 16, the record forR. bilobus is new. There is no statistically significant difference between the karyotypes ofR. seguieri andR. alpestris s. str. Nevertheless, according to morphological evidence and crossing experiments,R. seguieri is not closely related to theR. alpestris group.
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13.
《Journal of bryology》2013,35(3):367-377
Abstract

Two new Riccia species, R. somaliensis and R. erubescens from Africa are described and illustrated. They are both classified in the subgenus Riccia, section Riccia. R. somaliensis has hyaline, somewhat frilly scales and apolar, wingless spores; R. erubescens has shiny dark, purple-red to bright cherry-red scales and polar, winged spores with numerous small areolae; its tissues are sometimes distorted by gelatinous globules that are gradually extruded on the dorsal surface.  相似文献   

14.
Summary Reciprocal crosses were performed between Rumex tuberosus and two other taxa belonging to the Acetosa group: R. acetosa and R. thyrsiflorus. All three taxa are dioecious with the same chromosome numbers, XX + 12A, XYY+12A, but they differ from one another in the morphology of some autosomes. R. tuberosus and R. thyrsiflorus are similar in external morphology, while R. acetosa differs greatly from the other two taxa in external morphology as well as ecological characteristics.The F 1 and F 2 hybrids were fully vigorous and viable but their fertility was greatly reduced. Meiotic irregularities were observed in hybrids derived from all crosses. The most remarkable meiotic irregularity was diad formation after first meiotic division. The unreduced gametes derived from diads were responsible for the high frequency of polyploidy observed among the F 2 hybrids. In the cross R. tuberosus × R. acetosa the whole F 2 generation was tetraploid.It is concluded from the analysis performed that R. tuberosus, R. acetosa and R. thyrsiflorus are separate species, closely related to one another but already isolated by genetic and ecological barriers.  相似文献   

15.
Résumé L'étude infrastructurale des nerfs cardiaques afférents et des nerfs allato-cardiaques qui entrent dans la constitution du système neurosécréteur rétrocérébral de Locusta migratoria migratorioides (R. et F.) révèle l'existence des trois types de fibres neurosécrétrices définis dans les corpora cardiaca. Une quatrième catégorie de fibres caractérisées par la présence de vésicules claires existe dans les nerfs allato-cardiaques et dans les corpora allata. L'origine des fibres et l'évolution des grains de neurosécrétion au cours de leur transit sont envisagées.
Ultrastructural study of the retrocerebral neurosecretory system in Locusta migratoria migratorioides (R. et F.)II. Neurosecretory pathways
Summary An ultrastructural study of the nervi corporis cardiaci and nervi corporis allati, which are part of the retrocerebral neurosecretory system of Locusta migratoria migratorioides, reveals the existence of three neurosecretory fiber types. A fourth neurosecretory fibertype with electron lucent vesicles is also present in the nervi corporis allati and in the corpora allata. The fibers are characterized by differences in the size and electron opacity of the neurosecretory granules. The origin of the various neurosecretory fiber types and the evolution of the neurosecretory granules are discussed.
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16.
The allozyme variation among water frogs of the species R. balcanica, R. levantina and R. ridibunda, all formerly considered as one species (R. ridibunda Pallas, 1771), was studied using horizontal starch gel electrophoresis. Blood samples (N # 63) of frogs were collected from five populations in Greece and Israel. Samples (N = 9) of the hybrid frog R. esculenta collected from a locality in Germany were used as an outgroup for phylogenetic analyses. Fifteen enzymes controlled by twenty presumptive loci were identified. Thirteen loci were polymorphic within or among the studied populations. Genetic differentiation among the species was considerably greater than among populations of the same species. Even at Nestos River where R. ridibunda and R. balcanica occur in the same habitats, individuals could be assigned to either species due to characteristic differences of the genotypes (GPI1). This indicates reproductive isolation among these species. The reconstruction of phylogenetic relationships among the three species based on the allozyme data corroborated the model presented on the basis of bioacoustic data: R. ridibunda and R. balcanica (Nei's genetic distance D = 0.0820) are sibling species pertaining to an Eurasian lineage, whereas R. levantina (distance to the European species D = 0.1780 - 0.1955) together with R. perezi represent an independent afroasian lineage.  相似文献   

17.
The present study is focused on the antimicrobial, antioxidant, cytotoxic, and DNA protective effects of methanol extract obtained from R. digitellata, R. fastigiata, R. fraxinea, and R. polymorpha species that are distributed in Turkey. The highest total phenol content was determined in R. digitellata (144.6 mgGAE/gextract), and the highest total amount of flavonoids was found in R. fastigiata (20.40 mgGAE/gextract). The content of usnic acid was determined by High-Performance Liquid Chromatography (HPLC) and the highest amount was found in R. digitellata. DPPH (1,1-diphenyl-2-picrylhydrazyl) and ABTS [2,2’-azinobis(3-ethylbenzathiazoline-6-sulfonic acid)] radical scavenging methods were used for antioxidant activity. R. fraxinea showed the highest DPPH⋅ and ABTS+⋅ scavenging activity. In addition, the DNA protective effect was investigated using pBR322 plasmid DNA, and; all studied species were found to have DNA protective effects. The antibacterial activity was investigated using the disc diffusion method, and the R. digitellata methanol extract showed the best results with a 12.35 mm zone on Proteus mirabilis. On the human lung cancer (A549) and breast cancer (MDA-MB-231) cell lines, cytotoxic activity was assessed using an MTT assay. All lichen extracts were found to have a significant cytotoxic effect on both cancer cell lines at 1000 μg/mL concentration. These results suggest that Ramalina species may be potential candidates for developing new phytopharmaceuticals and functional components.  相似文献   

18.
Dieter Schäfer 《Protoplasma》1969,67(2-3):237-247
Zusammenfassung Setzt man kultivierte Hühnerherzmyoblasten einer Röntgenbestrahlung von 2400 R aus und bleibt damit unter der Letaldosis (> 3000 R), so entstehen bald darauf im Cytoplasma lichtoptisch sichtbare Vakuolen, die sich submikroskopisch als elektronenlichte Aufblähungen verschiedener Herkunft erweisen. Neben Erweiterungen des perinukleären Spaltraumes, des endoplasmatischen Retikulums und des Golgi-Apparates kommt es zur Schwellung und völligen Vakuolisierung der Mitochondrien; außerdem treten im Grundplasma Leerräume auf. Die Mitochondrien degenerieren größtenteils und werden durch neue ersetzt. Zur Behebung aller Schäden benötigen die Zellen etwa 10 Stunden.
Damage and recovery of cultured cells after x- ray treatment
Summary Embryonic chicken heart cells cultivatedin vitro were irradiated by X-rays of a sublethal dose of 2400 R near to the lethal dose (> 3000 R). Soon after irradiation vacuoles were observed by phase contrast microscopy, which after examination by electron microscopy proved to be electron light dilatations of different origin. In addition to enlargements of perinuclear space, endoplasmic reticulum (ER) and Golgi-apparatus depleted mitochondria or parts of them as well as ribosome free areas in the groundplasm have been found. The mitochondria were destroyed to great extend and substituted by new ones. However all these damages were removed within 10 hours.


Für beratende Hilfe danke ich Herrn Professor Dr. R.Danneel und Herrn Professor Dr. N.Weissenfels, für technische Assistenz Fräulein S.Kliewer, Fräulein I.Rosocha, Frau G.Scheben und Frau B.Zarbock.  相似文献   

19.
The predatory reduviids Rhinocoris bicolor and R. tropicus were kept in the laboratory. Observations on their mating behaviour, oviposition, and responses to insect prey are described. Experiments on the responses to various models indicate the importance of visual (moving) and olfactory stimuli in inducing the predatory behaviour of both species. Intraspecific predatory behaviour is described and its relationship to sexual behaviour considered.
Zusammenfassung Die westafrikanischen Raubwanzen Rhinocoris bicolor und R. tropicus wurden im Labor bei 25,5 ±1,0° gehalten und untersucht.Es wird eine Darstellung des Balzverhaltens gegeben. Bei beiden Arten nimmt das Männchen vor dem Versuch zu kopulieren eine charakteristische Reitstellung an.Das Eiablageverhalten beider Arten wird kurz beschrieben. R. bicolor-Eier werden im Gelege dichter gepackt und regelmäßiger angeordnet als R. tropicus-Eier. Bei keiner der beiden Arten ergaben sich Beweise für Brutpflegeverhalten der Eltern gegenüber Eiern oder Nachkommen. Vielmehr wurden Weibchen beim Aussaugen ihrer eigenen, soeben geschlüpften Brut beobachtet.Beide Arten greifen ein weites Spektrum von Beuteinsekten an und saugen an ihnen. Die Aufeinanderfolge der Handlungen, die mit ihrem normalen Verhalten zur Beute verbunden sind, wird im einzelnen geschildert.Es wurden Experimente über das Auftreten oder Ausbleiben von vier ausgewählten Stadien der Reaktion auf die Beute durchgeführt, indem den Reduviiden verschiedene Modelle dargeboten wurden. Die Ergebnisse erbrachten eindeutige Hinweise für die Bedeutung sowohl visueller wie geruchlicher Reize bei der Induktion des Angriffsverhaltens beider Arten.Erwachsene Weibchen beider Arten überfielen und besaugten betäubte oder tote Erwachsene ihrer eigenen Art. Das kannibalistische Verhalten der Männchen wurde durch ihre sexuellen Reaktionen überlagert. So nahmen sie gegenüber lebenden oder toten Männchen der eigenen Art die Reitstellung an, bevor sie an ihnen saugten, während sie vor dem Besaugen toter Weibchen außerdem auch zu kopulieren versuchten. Die Folgerungen aus diesem intraspezifischen Verhalten werden betrachtet.Die Ergebnisse werden im Hinblick auf frühere Arbeiten des Verfassers, einschließlich einer Paralleluntersuchung an Pisilus tipuliformis, diskutiert.
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20.
Nutlets of Hemigenia R.Br. and Microcorys R.Br. were examined using SEM. Significant variation, mainly useful at the infrageneric level, was found in nutlet shape, nature of the attachment scar, nature of surface sculpturing, exocarp cell shape and sculpturing, and nature of the indumentum. Typical nutlets are ovoidal, strongly reticulate or rugose. The exocarp cells are isodiametric and convex to papillate. Also common are cylindrical nutlets, often with longitudinal ridging and papillate exocarp cells. Surface pitting and concave exocarp cells are rare. A cladistic analysis of nutlet characters suggests both Hemigenia and Microcorys are polyphyletic, and Microcorys paraphyletic with respect to Westringia Sm. Notwithstanding that, the infrageneric classification of Hemigenia was largely supported, while in Microcorys, there was support for sect. Hemigenioides, but sects Anisandra and Microcorys were not resolved as distinct.  相似文献   

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