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1.
Mirle Ferrer Angel Snchez-Lamar Jorge Luís Fuentes Jordi Barb Montserrat Llagostera 《Mutation Research - Genetic Toxicology and Environmental Mutagenesis》2001,498(1-2)
Phyllanthus orbicularis is a medicinal plant, endemic to Cuba, whose aqueous extract has proven antiviral properties. This plant extract is being studied for treatment of viral diseases in animals and humans. Antimutagenic activities of this plant aqueous extract have been investigated as an additional and possible valuable property. Antimutagenesis was assayed against the mutagenic activity of m-phenylenediamine (m-PDA), 2-aminofluorene (2-AF), 1-aminopyrene (1-AP), 2-aminoanthracene (2-AA) and 9-aminophenantrene (9-AP) in Salmonella typhimurium (S. typhimurium) YG1024, in different co-treatment approaches. This plant extract produced a significant decrease of the mutagenesis mediated by these aromatic amines (AA) in the following order: m-PDA>2-AA>2-AF>9-AP>1-AP. Interactions with S9 enzymes and transformation of promutagenic amines and their mutagenic metabolites by chemical reactions to non-mutagenic compounds are proposed as possible mechanisms of antimutagenesis. Mutagenesis mediated by m-PDA was almost completely abolished when S9 mixture was co-incubated with the plant extract during 40 min, previous to the addition of the m-PDA and bacterial cells to the assay. Similar results were found with 2-AA and 1-AP, but the reduction of the mutation rate was not so dramatic. In contrast, the most significant antimutagenic effect against 2-AF and 9-AP was seen when these chemicals were co-incubated with the plant extract, before addition of the S9 mixture and bacterial cells to the assay. Therefore, inhibition or competition for S9 enzymes seems to be the main antimutagenic mechanism of this plant extract against m-PDA, 2-AA and 1-AP, whilst a chemical modification of 2-AF and 9-AP into non-promutagenic derivatives is likely to be the main mechanism of antimutagenesis against both compounds. 相似文献
2.
The European pond turtle Emys orbicularis, is an endangered species in Poland. The region of the Ilanka River, in the western part of the country (Lubuskie province),
is the most densely inhabited area by the species. Several populous sites are dispersed over the whole area of the province.
Over the past 10 years, 279 turtles were captured at 11 sites. In 218 individuals, those with a straight carapace length (SCL)
between 2.10–12.10 cm, sex was not determined; the remaining 61 with SCL 13.33–19.85 cm were sexed. Females had bigger bodies
and were heavier than males. The SCL of females was 17.10 ± 1.7 cm (average ± SD, n = 33), their body mass (BM) was 790.6 ± 228.7 g (n = 27), and in the case of males SCL was 15.44 ± 1.5 cm and BM was 554.2 ± 138.8 g (n = 28). SCL of the smallest egg laying female was 15.30 cm, and SCL of the smallest mating male was 13.33 cm. The colouration
of the turtles which undergoes change with age can be varied. 相似文献
3.
The morphology of many hypogeous fungi converges on a homogeneous reduced form, suggesting that disparate lineages are subject to a uniform selection pressure. The primary goal of this study was to evaluate the morphology and infer the phylogeny of the Leucogastrales with Mycolevis siccigleba using a Bayesian methodology. A comprehensive morphological assessment was used for an a priori phylogenetic inference to guide the sequencing effort. All structures except spore ornamentation pointed to the Albatrellaceae as the most likely sister taxon. Polyporoletus sublividus, a close relative of Albatrellus, produces ornamented basidiospores with a similar structure to M. siccigleba basidiospores. The ITS from 30 taxa was used for the molecular phylogenetic analysis. P. sublividus was found sister to Mycolevis. Leucophleps spinispora and L. magnata formed a group sister to the Polyporoletus/Mycolevis group, whereas Leucogaster was polyphyletic with respect to the core of the Leucogastrales and sister to A. caeruleoporus. This relationship was expected as previously undescribed chlamydospores produced by members of Albatrellus had a similar morphology to the basidiospores of L. rubescens. 相似文献
4.
Revision and reclassification of three Plasmopara species based on morphological and molecular phylogenetic data 总被引:1,自引:0,他引:1
Based on the results of morphological and DNA sequence (partial D1–D3/D7–D8 nuLSU and partial nuSSU-ITS1-5.8S rDNA) data, three species of Plasmopara are revised and reclassified. A species of Plasmopara parasitic on Scorzonera, invalidly published several times, is assigned to a new genus and species under Novotelnova scorzonerae. Plasmopara euphrasiae sp. nov. is segregated from P. densa, and P. centaureae-mollis is revised and relegated to synonymy of Bremia centaureae. All taxa are described and illustrated. 相似文献
5.
Archaeolemur 《Journal of human evolution》2001,41(6):545-576
Among the best known of recently extinct Malagasy lemurs is Archaeolemur, which is represented by many hundreds of specimens. The phylogenetic affinities of this taxon are unclear, especially in light of recent preliminary analysis of ancient DNA which does not support its previously accepted close relationship with the living Indridae. We examined the nearly complete skeletons of two adults and one juvenile and other less complete specimens to reconstruct aspects of the ontogeny of Archaeolemur. To compare the development of Archaeolemur to that of living strepsirrhines we collected data on Propithecus verreauxi, Eulemur fulvus, and Lemur catta. Additionally, because Archaeolemur exhibits some morphological convergences with distantly related papionins, we tested for convergence in the developmental patterns of Archaeolemur and Macaca fascicularis. Data include the status of tooth eruption, craniofacial sutural closure, and postcranial epiphyseal fusion, as well as linear measurements. We used discriminant function analysis and other tools to explore ontogenetic similarities and differences. The adaptive and phylogenetic significance of ontogenetic information is discussed. Our analysis shows that Archaeolemur displays a clear strepsirrhine pattern of development with only minor macaque convergences. Among the Strepsirrhini, Archaeolemur is slightly more similar developmentally to E. fulvus and L. catta than to P. verreauxi. Some of the distinctive features of the ontogeny of Archaeolemur may be related to diet, while others bear apparent testimony to a relatively rapid absolute pace of growth and development. 相似文献
6.
The 1997 check list of Dolichopodidae of the Czech Republic and Slovakia has recently been reviewed and updated. The new species list includes 346 species with 22 species added as new to the fauna of the Czech Republic. While the check list itself is published elsewhere, largely unpublished new records of Hercostomus argentifrons, H. nigrilamellatus, Medetera adjaniae, M. melancholica and M. setiventris are presented here, together with data on their distribution in Europe and their biology and ecology. The status of the newly added Sympycnus desoutteri is discussed. H. argentifrons is recorded here for the first time from the Czech Republic (Bohemia; Moravia) and background information is given on its discovery. While the Czech fauna with 324 species can be considered well known, the fauna of Slovakia is definitely much richer than its current national list of 217 species suggests. In the latter country, in particular surveys of sandy habitats with heathland or peatmoor, saltmarshes, reedmarshes, humid forests on loamy soils, and of rothole and saprun microhabitats on trees might quickly yield new species records. 相似文献
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9.
The marine alga Caulerpa taxifolia Vahl (C. Agardh), recognized globally as one of the most prolific non-native species introductions, has been introduced to
several temperate locations from where it has since rapidly expanded. C. taxifolia is protected by a toxin (terpenoid) in its tissues that limits grazing by native herbivores. Sacoglossan molluscs of the
genus Elysia are among the few organisms that graze C. taxifolia; however, little is known about their feeding ecology. In the current study, we quantified the grazing rates of Elysia tomentosa on native C. taxifolia (Moreton Bay, Queensland) and introduced C. taxifolia (Botany Bay and Lake Conjola, New South Wales). Grazing rates were similar at Moreton Bay sites and Botany Bay; however,
they were significantly lower in Lake Conjola. At the maximum observed grazing rate, slugs ate their body weight in C. taxifolia (dry weight) every 18–24 h. Differences in grazing rates between locations may be explained by differences in C. taxifolia morphology rather than native or introduced origin.
Handling editor: J. Padisak 相似文献
10.
Guillermo Velo-Antón Mario García-París Adolfo Cordero Rivera 《Conservation Genetics》2008,9(5):1263-1274
The European pond turtle (Emys orbicularis) is threatened and in decline in several regions of its natural range, due to habitat loss combined with population fragmentation.
In this work, we have focused our efforts on studying the genetic diversity and structure of Iberian populations with a fine-scale
sampling (254 turtles in 10 populations) and a representation from North Africa and Balearic island populations. Using both
nuclear and mitochondrial markers (seven microsatellites, ∼1048 bp nDNA and ∼1500 bp mtDNA) we have carried out phylogenetic
and demographic analyses. Our results show low values of genetic diversity at the mitochondrial level although our microsatellite
dataset revealed relatively high levels of genetic variability with a latitudinal genetic trend decreasing from southern to
northern populations. A moderate degree of genetic differentiation was estimated for Iberian populations (genetic distances,
F
ST
values and clusters in the Bayesian analysis). The results in this study combining mtDNA and nDNA, provide the most comprehensive
population genetic data for E. orbicularis in the Iberian Peninsula. Our results suggest that Iberian populations within the Iberian–Moroccan lineage should be considered
as a single subspecies with five management units, and emphasize the importance of habitat management rather than population
reinforcement (i.e. captive breeding and reintroduction) in this long-lived species. 相似文献
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12.
Maximilian Weigend Marc Gottschling Federico Selvi Hartmut H. Hilger 《Molecular phylogenetics and evolution》2009,52(3):755-768
Phylogenetic relationships are complex within the Lithospermeae, a large subgroup of the Boraginaceae s.str. The relationships of New World Lasiarrhenum, Macromeria, Nomosa, Onosmodium, Perittostoma, and Psilolaemus to subcosmopolitan and much larger Lithospermum have not been critically investigated in the recent past. No molecular data on the phylogeny of these genera and Lithospermum have so far been published. We investigated the relationships within Lithospermeae using three loci (nuclear ITS plus 5.8S rRNA, chloroplast trnL-F-spacer, and trnS-G-spacer) and micromorphological character traits (pollen, nutlets). Lithospermum s.l. constitutes the sistergroup of Asian Ulugbekia and is monophyletic only when its American segregates “Macromeria”, monotypic Nomosa, and Onosmodium are included. Both the African and the South American species groups of Lithospermum are monophyletic, but North American representatives are not resolved in a single clade. Morphological characters that have been considered as important for generic delimitation in the past (such as large, yellow corollas without faucal scales, particular pollen types, coarsely veined leaves, shrubby habit) have evolved in at least two only distantly related lineages within Lithospermum s.l. The reduction of American “Macromeria”, Nomosa, and Onosmodium as well as Asian Ulugbekia under Lithospermum is proposed to render the latter monophyletic. This redefined Lithospermum s.l. appears to have undergone a type of recent “island radiation” in the Americas, reflected in a morphological diversity far exceeding that found in the Old World. 相似文献
13.
Elwyn L. Simons Laurie R. Godfrey William L. Jungers Prithijit S. Chatrath Jeannette Ravaoarisoa 《International journal of primatology》1994,15(5):653-682
We diagnose new subfossil specimens belonging to the extinct palaeopropithecid, Mesopropithecus,from several caves at the Ankarana massif in northern Madagascar. They include three partial crania with mandibles, and the
first vertebrae, ribs, clavicle, pelvis, ulna, and hand and foot bones of Mesopropithecusever found. Several other postcranial elements are known for this northern variant of Mesopropithecusand for previously described species from central and southern Madagascar. The new materials cannot be accommodated in either
currently recognized species of this genus and are,hereby, given the name Mesopropithecus dolichobrachion. M. dolichobrachionis the second new species of extinct subfossil lemur to be found in the caves of Ankarana. It is unlike the two previously
described species of this genus primarily in its larger size, different limb proportions, and aspects of its long bone morphology.
Most notable is the fact that this is the only species of Mesopropithecuswith the forelimb longer than the hind limb— hence the name, the “long-armed” Mesopropithecus.Various characteristics place M. dolichobrachionphenetically closest (of species belonging to Mesopropithecus)to Babakotia radofilai, Archaeoindris,and Palaeopropithecus.If these similarities are derived specializations rather than primitive for palaeopropithecids, a new generic name will be
required. 相似文献
14.
Jaime B. Blanco-Dios Zheng Wang Manfred Binder David S. Hibbett 《Mycological Research》2006,110(10):1227-1231
Sparassis miniensis, collected in Pinus pinaster forests in Galicia (northwest Iberian Peninsula) is described as a new species, based on morphological and molecular data. Sparassis miniensis is morphologically distinct from all other species in the genus Sparassis based on scattered flabellae, which are strongly laciniated, azonate, and arise from an orange to rose-purplish base. The sporadic presence of clamp connections is restricted to subhymenial hyphae. Molecular data from LSU-rDNA, ITS and partial gene coding RNA polymerase subunit II (rpb2) suggest a close relationship between the new species S. miniensis and S. brevipes, another European species producing large fruiting bodies but with entire flabellae and no clamp connections. 相似文献
15.
Sa Peng Na Feng Meili Guo Yuehua Chen Qinghua Guo 《Biochemical Systematics and Ecology》2008,36(7):531-538
Genetic diversity of 23 populations of Carthamus tinctorius L. and two populations of Carthamus lanatus L. in China was investigated using Sequence-related Amplified Polymorphism (SRAP). All populations could be uniquely distinguished by 30 primer combinations with 483 bands and 274 polymorphic bands which generated 57% of polymorphic ratio. Unweighed pair-group method of with arithmetical averages (UPGMA) cluster analysis enabled construction of a dendrogram for estimating genetic distances among different populations. The extreme variation was observed when No. 4 cultivated and No. 13 wild population of C. lanatus were grouped at GS = 0.58, and separated from 23 populations of C. tinctorius at GS = 0.10. The result suggested that the cultivated and wild populations of C. lanatus had close relationship with each other and far relationship with C. tinctorius. Dendrogram also revealed a large genetic variation in 23 C. tinctorius populations; different primer combinations allowed them distinctly distinguished one from others with relatively low genetic similarity. Furthermore, five typical representative fragments in C. lanatus were obtained by four most informative primer combinations, which provided a possibility to distinguish C. lanatus from the C. tinctorius evidently. 相似文献
16.
Patrice C. Peart Kayanne P. McCook Floyd A. Russell William F. Reynolds Paul B. Reese 《Steroids》2011,76(12):1317-1330
The potential of Fusarium oxysporum var. cubense UAMH 9013 to perform steroid biotransformations was reinvestigated using single phase and pulse feed conditions. The following natural steroids served as substrates: dehydroepiandrosterone (1), pregnenolone (2), testosterone (3), progesterone (4), cortisone (5), prednisone (6), estrone (7) and sarsasapogenin (8). The results showed the possible presence of C-7 and C-15 hydroxylase enzymes. This hypothesis was explored using three synthetic androstanes: androstane-3,17-dione (9), androsta-4,6-diene-3,17-dione (10) and 3α,5α-cycloandrost-6-en-17-one (11). These fermentations of non-natural steroids showed that C-7 hydroxylation was as a result of that position being allylic. The evidence also pointed towards the presence of a C-15 hydroxylase enzyme.The eleven steroids were also fed to Exophialajeanselmei var. lecanii-corni UAMH 8783. The results showed that the fungus appears to have very active 5α and 14α-hydroxylase enzymes, and is also capable of carrying out allylic oxidations.Ceratocystis paradoxa UAMH 8784 was grown in the presence of the above-mentioned steroids. The results showed that monooxygenases which effect allylic hydroxylation and Baeyer–Villiger rearrangement were active. However, redox reactions predominated. 相似文献
17.
Fungal endophytes of native Gossypium species in Australia 总被引:1,自引:0,他引:1
Bo Wang Michael J. Priest Amy Davidson Curt L. Brubaker Matt J. Woods Jeremy J. Burdon 《Mycological Research》2007,111(3):347-354
Fungal endophytes of 17 genera were found in stems of four native Gossypium species (G. australe, G. bickii, G. nelsonii, G. sturtianum) collected from inland areas in Queensland, the Northern Territory, and South Australia in 2001. Phoma, Alternaria, Fusarium, Botryosphaeria, Dichomera, and Phomopsis were common, accounting for 58, 18, 11, 3, 1, and 1 % of the 281 recovered isolates, respectively, and occurring in 47, 29, 19, 5, 5, and 4 % of the 79 sampled populations. Among the four Gossypium species in Queensland and the Northern Territory, Alternaria spp. and Fusarium spp. had the greatest recovery frequency in G. bickii stems. The recovery frequencies of Phoma spp. and Alternaria spp. were significantly greater in the G. sturtianum stems collected from South Australia than in those from Queensland and the Northern Territory. Pathogenicity of 42 representative isolates was tested on cultivated cotton (G. hirsutum). All isolates caused some localized discoloration in stem tissue when inoculation was conducted with the stem puncturing method, but none of the isolates could induce any foliar symptoms during the five-week experimental period by either inoculation method (root dipping or stem puncturing), suggesting that the endophytic fungi of native Gossypium species are unlikely sources of cotton pathogens. 相似文献
18.
In this study, thirty-six individuals of Acheilognathus macropterus were collected from the Heilongjiang River, the Yangtze River, and the Nandujiang River. Partial mitochondrial cytochrome
b gene region (636 base pair) was sequenced to these samples and 22 haplotypes were found. With A. chankaensis and A. tokinensis as outgroups, their relationships were analyzed. The p-distances were calculated with Mega software and a molecular phylogenetic tree was constructed using the neighbor-joining
(NJ) method. The proportions of main morphological characters were compared as well. P-distances showed that the genetic differences in A. macropterus samples were far smaller than those between these samples and the outgroups. The molecular phylogenetic tree shows that samples
with barbels and those without barbels were intermingled. There was no distinctive difference in proportions of morphological
characteristics among them. These results suggested that samples with barbels and those without barbels (formally identified
as A. taenianalis) are the same species; A. taenianalis is synonymous with A. macropterus. The thirtysix individuals were grouped into five clades and the positions of the samples in the clades were correspondingly
grouped within their geographical distributions. Among the five clades, clades 1 and 5 included samples from the Heilongjiang
River and Nandujiang River respectively. The samples from the Yangtze River scattered into clades 2, 3, and 4. There were
distinctive genetic differences (>5%) among them. Interestingly, the distributions of the 21 samples in these three clades
were not correlated to their geographical distributions. It is postulated that these genetic differences were due to the bitterlings’
mating choice mechanism, the prozygotic isolation. The genetic differences between the fish from Nandujiang River and those
from the mainland indicated that they were separated early. However, the small genetic differences among the samples and the
positions of the fish from the Heilonjiang River in the molecular phylogenetic tree indicate that fish in Heilongjiang River
might have dispersed from the Yangtze River to that area much later.
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Translated from Acta Hydrobiologica Sinica, 2006, 39(2): 134–140 [译自: 水生生物学报] 相似文献
19.
I. Literák V. Mrlík A. Hovorková P. Mikulíček J. Lengyel K. Št’astný J. Cepák L. Dubská 《European Journal of Wildlife Research》2007,53(3):195-203
The population of white-tailed sea eagles (Haliaeetus albicilla) in the Czech Republic declined dramatically during the twentieth century. None were observed in the area for more than 60 years
until population recoveries were observed beginning in the 1980s. It is currently estimated that 25–30 breeding pairs of white-tailed
sea eagles nest in the Czech Republic. This article analyses surveillance data from three periods between 1973 and 2003 on
the occurrence and nesting of white-tailed sea eagles in the Czech Republic. We investigated recolonization of European white-tailed
sea eagles in the Czech Republic in terms of migration patterns and population structures. Bird ringing data suggest the Czech
population may be recovered from various areas encompassing northern Europe. Using data collected by DNA microsatellite, no
population structure was revealed through Bayesian and cluster analyses with an existing Hardy–Weinberg equilibrium, which
suggests mixed panmictic populations of white-tailed sea eagles in the Czech Republic and Slovakia. While analysis of genetic
diversity showed no difference between recovered populations in the southeastern Czech Republic and those persisting in Slovakia,
there was genetic diversity between eagles of the southeastern subpopulation and eagles in other parts of the Czech Republic.
Taken together, these observations on the population structure of white-tailed sea eagles in the Czech Republic imply that
other European birds contributed to the recovery of the Czech population, likely through breeding mixture with an identifiable
centre in the southeastern Czech Republic. 相似文献
20.
Growth of Phragmites australis and Phalaris arundinacea in constructed wetlands for wastewater treatment in the Czech Republic 总被引:1,自引:0,他引:1
Common reed (Phragmites australis) and reed canarygrass (Phalaris arundinacea) are two most commonly used plant species in constructed wetlands for wastewater treatment in the Czech Republic. Growth characteristics of both plants (biomass, stem count, and length) have been measured in 13 horizontal sub-surface flow constructed wetlands since 1992. The results revealed that while Phalaris usually reaches its maximum biomass as early as during the second growing season, Phragmites usually reaches its maximum only after three to four growing seasons. The maximum biomass of both species varies widely among systems and the highest measured values (5070 g m−2 for Phragmites and 1900 g m−2 for Phalaris) are similar to those found in eutrophic natural stands. The shoot count of Phragmites decreases after the second growing season while length and weight of individual shoots increases over time due to self-thinning process. Number of Phalaris shoots is the highest during the second season and then the shoot count remains about the same. Also the shoot length remains steady over years of constructed wetland operation. 相似文献