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1.
Haemoproteus velans Coatney and Roudabush 1937 and H. borgesi Tendeiro 1947 are redescribed and illustrated. Haemoproteus bennetti sp. n. is described. Haemoproteid records from woodpeckers are listed.  相似文献   

2.
The avian haemoproteid, Haemoproteus centropi de Mello, a blood parasite found in members of the family Cuculidae, is redescribed from Clamator jacobinus Boddaert from Ngulia in Kenya. Haemoproteus froilanoi Tendeiro is considered to be a synonym of H. centropi. The reasons for this are discussed.  相似文献   

3.
Conocybe huijsmanii Watling, C. elegans Watling and C. parvula Dossing & Watling are described as new species. Bolbitius lacleus J. E. Lange is redescribed and neotypified, and C. utriformis P. D. Orton is recorded for the first time for Denmark. Short notes on a collection agreeing with Jakob E. Lange's interpretation of Pholiota brunneola and on Danish material of Agrocybe firma (Peck) Singer are offered.  相似文献   

4.
The relatively small number of passenger pigeon bones found in prehistoric sites in the eastern United States is at variance with the tremendous population recorded between the seventeenth and nineteenth centuries: It is argued that, prior to European contact, the population of passenger pigeons was small due to human-wildlife competition over tree nuts. This competition restricted the pigeon's access to food and limited its prehistoric population. When this competitive network was disrupted by European colonization, the availability of food for the pigeon increased. The enormous population that then emerged represents an outbreak population precipitated by enrichment in food and space. The structure of the prehistoric food web in the forests of the eastern United States is diagrammed, and the process leading to the growth of the passenger pigeon population described.  相似文献   

5.
Illustrated keys to males and females of the 13 known species of the Indo-Australian braconine genus Macrobracon Szépligeti are provided. Principal components analysis has been conducted to aid in the recognition. All known species are redescribed. Two new species are described: M. flavus from Malaysia and Indonesia and M. unicolor from Taiwan.  相似文献   

6.
To determine the origin of the tetraploid annuals Microseris campestris and M. acuminata , chloroplast RFLP, RAPD and ITS sequence variability among nine populations of the two polyploids and 14 populations of the diploid annuals M. elegans and M. douglasii have been surveyed. Previously described variable chloroplast restriction sites infer M. douglasii as the possible maternal parent of both tetraploid species. However, the chloroplast genome typical for M. douglasii has now also been found in some plants of M. elegans . RAPD analysis revealed 172 polymorphic DNA markers that defined all four species as genetically distinct groups, but demonstrated closer associations between M. douglasii and M. acuminata , and between M. elegans and M. campestris . Sequencing of the ITS-1 and ITS-2 region yielded 73 phylogenetically informative sites. Thirty base-pair mutations separated the annual Microseris species from the outgroup, Uropappus lindleyi . The putative interspecific allotetraploid M. campestris contained only one type ITS sequence that, on the basis of eight synapomorphic substitutions was derived from M. elegans . The single ITS of M. acuminata shares six common sites with M. douglasii . Surprisingly, six sites were synapomorphic for the two tetraploids, M. campestris and M. acuminata , suggesting recombination within the ITS of both species with that of a common, now extinct, parental taxon, possibly the donor of the M. douglasii type chloroplasts found in both tetraploids. These results confirm the interpretation of M. campestris as derived from M. douglasii (extinct population) and M. elegans , and resolve the unknown origin of M. acuminata as an intraspecific hybrid between two very distinct populations of M. douglasii , one of them the same extinct M. douglasii form that contributes to M. campestris .  相似文献   

7.
Coregonus oxyrinchus is redescribed and a neotype is designated (BMNH 1862.11.20.1.). It was restricted to south England and the lower parts of the Rivers Rhine, Meuse and Schelde. It is now globally extinct; the last individual was caught in 1940. Coregonus oxyrinchus is distinguished from other coregonids by having 38–46 gill rakers and a long, pointed snout.  相似文献   

8.
Cryptococcus neoformans was cultured from 9 (1%) of 835 clinical specimens examined from the respiratory tract of patients. These isolations came from 3 (0.4%) of the760 patients; 8 isolates were from sputum and one from urine. The fungus was not demonstrable in the air at a selected site during a 2-year study although other species of Cryptococcus, namely, C. albidus, C. ater, C. flavus, C. laurentii, C. magnus, C. terreus and C. uniguttulatus were isolated. The three C. neoformans positive patients were males, with pulmonary tuberculosis as the primary disease and history of repeated exposure to pigeon excreta in two. None of these patients manifested any overt signs and symptoms specificially attributable to cryptococcosis, nor did they receive any antifungal therapy. Repeated isolations of C. neoformans from sputum, a positive urine culture and demonstration of cryptococcal antibodies in a serum specimen, followed by negative cultures and serology, suggested that patient 1 had spontaneously recovered from an episode of benign, minimal pulmonary cryptococcosis. Patients 2 and 3 probably carried the fungus as a transient resident of the respiratory tract. The results suggest that C. neoformans is of uncommon occurrence in the respiratory tract of patients with bronchopulmonary disorders and that the isolation of the fungus from this site may not necessarily imply an etiologic relationship.  相似文献   

9.
Laboratory assays were performed with detached milk stage maize ( Zea mays L.) ears and dusky sap beetles ( Carpophilus lugubris Murray) carrying the Kodiak Concentrate formulation of the bacterium, Bacillus subtilis (Ehrenberg) Cohn. After 1 day of exposure to the B. subtilis- contaminated C. lugubris , the colonization of mechanically damaged kernels by Aspergillus flavus Link ex. Fries was reduced from 82% (if the A. flavus was inoculated first) to 41% (if B. subtilis was added by C. lugubris before the A. flavus ). Field cage studies were performed with an autoinoculative device containing B. subtilis into which C. lugubris beetles were introduced. C. lugubris -dispersed B. subtilis reduced visible A. flavus colonization by 97% when the A. flavus was added to purposely damaged maize ears 4 days after C. lugubris were released from the autoinoculator. In 1993 field studies, none of the purposely damaged ears that allowed access to C. lugubris beetles emerging from autoinoculators containing B. subtilis had visible sporulating A. flavus compared with 92% of ears that did not allow access of C. lugubris but that subsequently had the A. flavus inoculum added. In 1994 field studies, 70% of the ears that excluded C. lugubris had aflatoxin levels greater than 200 ppb in purposely damaged kernels, as opposed to less than 10% of kernels that permitted access by natural populations of C. lugubris that probably acquired B. subtilis from a single autoinoculator. Aflatoxin levels in these ears were negatively correlated with the presence of both B. subtilis and C. lugubris . The B. subtilis was widely dispersed over a 16-ha area as indicated by maize ear and C. lugubris trap sampling. These studies indicate that autoinoculative dispersal of B. subtilis by natural populations of C. lugubris is a potentially useful means for reducing A. flavus and aflatoxin in maize.  相似文献   

10.
Confluaria multistriata (Rudolphi, 1810) is redescribed on the basis of specimens from Tachybaptus ruficollis from the material of Rudolphi and Dollfus and new specimens from the same host species from Bulgaria. The types of C. japonica (Yamaguti, 1935) from T. ruficollis are also redescribed and figured. A single specimen from the collection of Krabbe, described as Taenia multistriata, is re-examined and recognised as belonging to a different species of Confluaria, the status of which remains to be established. Criteria for distinguishing the three species are proposed. In view of the present results, some of the previous records of C. multistriata and C. japonica are re-evaluated. The synonymy of the genera Colymbilepis Spasskaya, 1966 and Confluaria Ablasov in Spasskaya, 1966 is confirmed.  相似文献   

11.
Complementary experiments were performed to indicate the presence or absence of sialic acids in axenically cultured Panagrellus redivivus and Caenorhabditis elegans. Competitive displacement experiments with radiolabeled Limax flavus agglutinin demonstrated the presence of sialic acid in nematodes grown in medium which contained liver extract as a growth factor but the absence of sialic acid when heme was substituted for liver extract. This finding suggested that sialic acid present in the liver medium was responsible for conflicting results of other studies. Transmission electron microscopy of thin sections from nematodes labeled with an LFA-ferritin conjugate revealed no label to the surface area of the cephalic chemosensilla. Fluorometric analysis with a modification of the thiobarbituric acid assay was negative for sialic acid. Analyses by gas chromatography-mass spectrometry, sensitive to the high picomole range, were also negative for sialic acid. Taken together the results provide evidence for the absence of sialic acid in P. redivivus and C. elegans using the most sensitive and diagnostic technique currently available.  相似文献   

12.
The strain ANU 6277 was isolated from laterite soil and identified as Streptomyces sp. closely related to Streptomyces albidoflavus cluster by 16S rRNA analysis. The cultural, morphological and physiological characters of the strain were recorded. The strain exhibited resistance to chloramphenicol, penicillin and streptomycin. It had the ability to produce enzymes such as amylase and chitinase. A bioactive compound was isolated from the strain at stationary phase of culture and identified as 3-phenylpropionic acid (3-PPA) by FT-IR, EI-MS, 1H NMR and 13C NMR spectral studies. It exhibited antimicrobial activity against different bacteria like Bacillus cereus, B. subtilis, Escherichia coli, Klebsiella pneumoniae, Proteus vulgaris, Pseudomonas aeruginosa, P. flourescens, Staphylococcus aureus and some fungi including Aspergillus flavus, A. niger, Candida albicans, Fusarium oxysporum, F. udum and Penicillium citrinum. The antifungal activity of 3-PPA of the strain was evaluated in in vivo and in vitro conditions against Fusarium udum causing wilt disease in pigeon pea. The compound 3-PPA is an effective antifungal agent when compared to tricyclozole (fungicide) to control wilt caused by F. udum, but it exhibited less antifungal activity than carbendazim.  相似文献   

13.
Mainly based on collections from Willershausen (Lower Saxony, North Germany), the Pliocene Heteroptera fauna of West Europe is briefly revised. The present compilation includes a checklist with taxonomic and systematic corrections ofJordan’s (1967, 1969) type materials. Naucoroid water bugs of the family Aphelocheiridae are distinguished and the extinct species of the genusAphelocheirus are redescribed. The new genusWillershausenia n.gen. (type species:Nabis strausi Jordan, 1969) is defined and transferred to the coreoid family Alydidae.   相似文献   

14.
Barrière A  Félix MA 《Genetics》2007,176(2):999-1011
Caenorhabditis elegans is a major laboratory model system yet a newcomer to the field of population genetics, and relatively little is known of its biology in the wild. Recent studies of natural populations at a single time point revealed strong spatial population structure and suggested that these populations may be very dynamic. We have therefore studied several natural C. elegans populations over time and genotyped them at polymorphic microsatellite loci. While some populations appear to be genetically stable over the course of observation, others seem to go extinct, with full replacement of multilocus genotypes upon regrowth. The frequency of heterozygotes indicates that outcrossing occurs at a mean frequency of 1.7% and is variable between populations. However, in genetically stable populations, linkage disequilibrium between different chromosomes can be maintained over several years at a level much higher than expected from the heterozygote frequency. C. elegans seems to follow metapopulation dynamics, and the maintenance of linkage disequilibrium despite a low yet significant level of outcrossing suggests that selection may act against the progeny of outcrossings.  相似文献   

15.
We had shown previously that all major glycoproteins of pigeon egg white contain Galalpha1-4Gal epitopes (Suzuki, N., Khoo, K. H., Chen, H. C., Johnson, J. R., and Lee, Y. C. (2001) J. Biol. Chem. 276, 23221-23229). We now report that Galalpha1-4Gal-bearing glycoproteins are also present in pigeon serum, lymphocytes, and liver, as probed by Western blot with Griffonia simplicifolia-I lectin (specific for terminal alpha-Gal) and anti-P1 (specific for Galalpha1-4Galbeta1-4GlcNAcbeta1-) monoclonal antibody. One of the major glycoproteins from pigeon plasma was identified as IgG (also known as IgY), which has Galalpha1-4Gal in its heavy chains. High pressure liquid chromatography, mass spectrometric (MS), and MS/MS analyses revealed that N-glycans of pigeon serum IgG included (i) high mannose-type (33.3%), (ii) disialylated biantennary complex-type (19.2%), and (iii) alpha-galactosylated complex-type N-glycans (47.5%). Bi- and tri-antennary oligosaccharides with bisecting GlcNAc and alpha1-6 Fuc on the Asn-linked GlcNAc were abundant among N-glycans possessing terminal Galalpha1-4Gal sequences. Moreover, MS/MS analysis identified Galalpha1-4Galbeta1-4Galbeta1-4GlcNAc branch terminals, which are not found in pigeon egg white glycoproteins. An additional interesting aspect is that about two-thirds of high mannose-type N-glycans from pigeon IgG were monoglucosylated. Comparison of the N-glycan structures with chicken and quail IgG indicated that the presence of high mannose-type oligosaccharides may be a characteristic of these avian IgG.  相似文献   

16.
Park HK  Suh D  Hyun M  Koo HS  Ahn B 《DNA Repair》2004,3(10):1375-1383
The xeroderma pigmentosum complementation group F (XPF) protein is a structure-specific endonuclease in a complex with ERCC1 and is essential for nucleotide excision repair (NER). We report a single cDNA of Caenorhabditis elegans (C. elegans) encoding highly similar protein to human XPF and other XPF members. We propose to name the corresponding C. elegans gene xpf. Messenger RNA for C. elegans xpf is 5'-tagged with a SL2 splice leader, suggesting an operon-like expression for xpf. Using RNAi, we showed that loss of C. elegans xpf function caused hypersensitivity to ultra-violet (UV) irradiation, as observed in enhanced germ cell apoptosis and increased embryonic lethality. This study suggests that C. elegans xpf is conserved in evolution and plays a role in the repair of UV-damaged DNA in C. elegans.  相似文献   

17.
Endogenous small interfering RNAs (siRNAs) are a class of naturally occuring regulatory RNAs found in fungi, plants, and animals. Some endogenous siRNAs are required to silence transposons or function in chromosome segregation; however, the specific roles of most endogenous siRNAs are unclear. The helicase gene eri-6/7 was identified in the nematode Caenorhabditis elegans by the enhanced response to exogenous double-stranded RNAs (dsRNAs) of the null mutant. eri-6/7 encodes a helicase homologous to small RNA factors Armitage in Drosophila, SDE3 in Arabidopsis, and Mov10 in humans. Here we show that eri-6/7 mutations cause the loss of 26-nucleotide (nt) endogenous siRNAs derived from genes and pseudogenes in oocytes and embryos, as well as deficiencies in somatic 22-nucleotide secondary siRNAs corresponding to the same loci. About 80 genes are eri-6/7 targets that generate the embryonic endogenous siRNAs that silence the corresponding mRNAs. These 80 genes share extensive nucleotide sequence homology and are poorly conserved, suggesting a role for these endogenous siRNAs in silencing of and thereby directing the fate of recently acquired, duplicated genes. Unlike most endogenous siRNAs in C. elegans, eri-6/7-dependent siRNAs require Dicer. We identify that the eri-6/7-dependent siRNAs have a passenger strand that is ~19 nt and is inset by ~3-4 nts from both ends of the 26 nt guide siRNA, suggesting non-canonical Dicer processing. Mutations in the Argonaute ERGO-1, which associates with eri-6/7-dependent 26 nt siRNAs, cause passenger strand stabilization, indicating that ERGO-1 is required to separate the siRNA duplex, presumably through endonucleolytic cleavage of the passenger strand. Thus, like several other siRNA-associated Argonautes with a conserved RNaseH motif, ERGO-1 appears to be required for siRNA maturation.  相似文献   

18.
19.
Celes akitanus was rediscovered in semi‐natural grasslands in Japan. This species is one of the most endangered insects in Japan; most local populations were thought to be extinct. Reliable records of this rare species had been obtained only from Yamagata, Niigata, Tokyo and Nagano Prefectures. We compared the morphology of the holotype of Oedipoda akitana (=C. akitanus) and newly collected specimens and found that they matched with each other. The species was redescribed based on the holotype and new specimens. A molecular phylogenetic analysis involving other acridid species indicated that our samples were practically identical to C. akitanus from China. We conclude that the specimens we collected are C. akitanus, which has been rediscovered in Japan after about 30 years. Because the discovered populations were restricted to narrow and scattered areas, conservation of these populations should be a high priority. Population monitoring and habitat assessment are required. Because C. akitanus and many other endangered species are found in the grassland areas, these habitats should be protected and maintained.  相似文献   

20.
The ecological niche that a species can occupy is determined by its resource requirements and the physical conditions necessary for survival. The niche to which an organism is most highly adapted is the realized niche, whereas the complete range of habitats that an organism can occupy represents the fundamental niche. The growth and development of Cryptococcus neoformans and Cryptococcus gattii on pigeon guano were examined to determine whether these two species occupy the same or different ecological niches. C. neoformans is a cosmopolitan pathogenic yeast that infects predominantly immunocompromised individuals, exists in two varieties (grubii [serotype A] and neoformans [serotype D]), and is commonly isolated from pigeon guano worldwide. By contrast, C. gattii often infects immunocompetent individuals and is associated with geographically restricted environments, most notably, eucalyptus trees. Pigeon guano supported the growth of both species, and a brown pigment related to melanin, a key virulence factor, was produced. C. neoformans exhibited prolific mating on pigeon guano, whereas C. gattii did not. The observations that C. neoformans completes the life cycle on pigeon guano but that C. gattii does not indicates that pigeon guano could represent the realized ecological niche for C. neoformans. Because C. gattii grows on pigeon guano but cannot sexually reproduce, pigeon guano represents a fundamental but not a realized niche for C. gattii. Based on these studies, we hypothesize that an ancestral Cryptococcus strain gained the ability to sexually reproduce in pigeon guano and then swept the globe.  相似文献   

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