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1.
RW Weber 《Canadian Metallurgical Quarterly》1998,80(2):141-5; quiz 146-7
LEARNING OBJECTIVES: The purpose of this review is to introduce the reader to a systematic approach to categorizing pollen types. This will enable the reader to recognize pollen characteristics of the most common botanical sources and determine the relevant contributors to the local aeroallergen burden. DATA SOURCES: Allergenic plant and pollen atlases for pollen characteristics, allergy texts for procedures and overviews, and relevant reviews from the English medical literature (1985 to present). RESULTS: By applying a visual gestalt utilizing grain number, size, shape, surface structures, and internal detail, one is able to identify pollen source to the appropriate botanical taxonomic level. Identification may be possible only to the family or order, but most frequently to the genus, and occasionally to the species. CONCLUSIONS: Outdoor sampling allows the identification of aeroallergen burden in a locale. In conjunction with field work, the relevant sources can be identified as well as time of pollination. This allows the physician to correlate symptoms with exposure and relevant sensitization.  相似文献   

2.
Examined odor preferences of 72 infant, juvenile, and adult Sprague-Dawley rats and 119 Syrian hamsters in a 2-choice situation following 3–10 days of differential olfactory exposure. Exposure increased preferences for a simple botanical odor in infants and juveniles but not adults of both species. Preference differences between exposure groups were greatest for infants, moderate for juveniles, and insignificant for adults, suggesting that olfactory sensitive periods occur in these altricial rodent species. Age of exposure differentially influenced responses to combinations of conspecific and botanical odors. Results suggest that olfactory experience has a similar impact on responses of rats and hamsters to botanical but not conspecific odors. (26 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

3.
A new approach to separate members of the genus Photobacterium from the genus Vibrio with RFLP (Restriction Fragment Length Polymorphism) patterns by HhaI digestion of PCR-amplified 16S rDNA was developed in the present study. It was clearly shown that these patterns of the genus Photobacterium were unique and distinguishable from Vibrio species. This method is very simple and does not need other supporting procedures, such as Southern transfer and probe hybridization. It can be applied not only to luminous species, but also to non-luminous Photobacterium spp. This result promises a rapid tool to distinguish the genus Photobacterium from Vibrio and should be useful in routine identification system.  相似文献   

4.
G-52 is a new broad spectrum aminoglycoside produced by a species of the genus Micromonospora, Micromonospora zionensis. It has been differentiated from other known related antibiotics by a variety of chemical and biological methods. Its in vitro and in vivo spectrum of activity appears to be quite similar to that of verdamicin and gentamicin but is differentiated from them by its increased activity against 6'-N-acetylating strains.  相似文献   

5.
To understand the mechanisms underlying displacement (the shift from nocturnal to diurnal activity), in one of the two coexisting spiny mice (genus Acomys), the effect of chemical cues released by A. cahirinus on the time of activity of A. russatus was tested Six golden spiny mice (A. russatus), which prior to the experiments were kept separate from common spiny mice (A. cahirinus), showed nocturnal activity. They were exposed to chemical cues from the urine and faeces of conspecific and heterospecific mice of the opposite sex. The onset of activity in these mice was recorded. While the urine and faeces of conspecific mice did not have a significant effect on the time of onset of activity, heterospecific urine and faeces did cause a significant (p < 0.001) time shift and, a day after they were introduced, activity started 6.8 +/- 1.9 h earlier. This shift also took place on the second day. The results of this study suggest that the mechanism for displacement of A. russatus from nocturnal activity is by chemical signals released by A. cahirinus. Therefore, it may be concluded that chemical cues maintain time separation between these two species.  相似文献   

6.
The distribution of putative catecholamines has been previously studied in the nervous system of three Promesostoma species using the glyoxylic-acid-induced fluorescence (GAIF) method. In this communication, the results are reported of a similar study of Promesostoma balticum, which is classified to another group of species in the genus. Promesostoma species from two different species groups differed in the position of neurons associated with the ventral and lateral cords. All the studied species of Promesostoma demonstrated doubled dorsal neurons in so called anterior complex (AnDo), a character which differentiates this genus from the other studied Typhloplanoida.  相似文献   

7.
Thirty-one strains received either as Actinomadura madurae or Actinomadura pelletieri were assigned to four phena, clusters 1 to 4, in a numerical phenetic survey of the genus Actinomadura. Clusters 2 and 4 corresponded to the validly described species A. madurae and A. pelletieri whereas clusters 1 and 3 encompassed strains received as A. madurae and A. pelletieri, respectively. The two clusters that contained A. madurae strains formed a single taxon when a dataset lacking the antibiotic sensitivity entries was examined. Results from pyrolysis mass spectrometric and DNA amplification fingerprinting analyses underpinned the taxonomic status of clusters 2, 3 and 4 and suggested that the A. madurae strains accounted for a relatively wide range of variation. It is proposed that the cluster 3 strains be given species status within the genus Actinomadura given the congruence found between the chemical, molecular and numerical phenetic data. The name Actinomadura latina is proposed for the new taxon. The type strain is DSM 43382.  相似文献   

8.
Phylogenetic relationships among Phlebotominae were inferred through a pilot study using parsimony analysis of the D2 domain of ribosomal DNA sequences: 455 pairs of bases were sequenced in nine species of Phlebotomine sandflies which belong to the genera Lutzomyia, Phlebotomus and Sergentomyia. Two taxa are used as outgroups: Psychoda sp. and Nemapalpus flavus which is the sister group of the Phlebotominae. The South American genus Lutzomyia appears to be monophyletic. The Mediterranean species Sergentomyia dentata is its sister group and is not clustered with the Old World genus Phlebotomus. The latter is a paraphyletic genus with an early individualization of the branch including the closely related subgenera Phlebotomus and Paraphlebotomus, and a late individualization of the subgenus Larroussius. These results have some consequences on the biogeography of the leishmaniasis in the Old World.  相似文献   

9.
The N-terminal sequences of malate dehydrogenases from 10 bacterial strains, representing seven genera of Proteobacteria, were determined. Of these, the enzyme sequences of species classified in the genus Brevundimonas clearly resembled those malate dehydrogenases with greatest similarity to lactate dehydrogenases. Additional evidence from subunit molecular weights, peptide mapping, and enzyme mobilities suggested that malate dehydrogenases from species of the genus Brevundimonas were structurally distinct from others in the study.  相似文献   

10.
Classification within the genus Pistacia has been based on leaf morphology and geographical distribution. Molecular genetic tools (PCR amplification followed by restriction analysis of a 3.2-kb region of variable chloroplast DNA, and restriction fragment length polymorphism analysis of the Pistacia cpDNA with tobacco chloroplast DNA probes) provided a new set of variables to study the phylogenetic relationships of 10 Pistacia species. Both parsimony and cluster analyses were used to divide the genus into two major groups. P. vera was determined to be the least derived species. P. weinmannifolia, an Asian species, is most closely related to P. texana and P. mexicana, New World species. These three species share a common origin, suggesting that a common ancestor of P. texana and P. mexicana originated in Asia. P. integerrima and P. chinensis were shown to be distinct whereas the pairs of species were monophyletic within each of two tertiary groups, P. vera:P. khinjuk and P. mexicana:P. texana. An evolutionary trend from large to small nuts and leaves with few, large leaflets to many, small leaflets was supported. The genus Pistacia was shown to have a low chloroplast DNA mutation rate: 0.05-0.16 times that expected of annual plants.  相似文献   

11.
There are numerous in vitro studies documenting the multiplication of Legionella species in free-living amoebae and other protozoa. It is believed that protozoa serve as host cells for the intracellular replication of certain Legionella species in a variety of environmental settings. This study describes the isolation and characterization of a bacterium initially observed within an amoeba taken from a soil sample. In the laboratory, the bacterium multiplied within and was highly pathogenic for Acanthamoeba polyphaga. Extracellular multiplication was observed on buffered charcoal yeast extract agar but not on a variety of conventional laboratory media. A 16S rRNA gene analysis placed the bacterium within the genus Legionella. Serological studies indicate that it is distinct from previously described species of the genus. This report also describes methods that should prove useful for the isolation and characterization of additional Legionella-like bacteria from free-living amoebae. In addition, the characterization of bacterial pathogens of amoebae has significant implications for understanding the ecology and identification of other unrecognized bacterial pathogens.  相似文献   

12.
R2 elements are non-long-terminal-repeat (non-LTR) retrotransposons that insert specifically in the 28S rRNA genes of many insects. Previous reports concerning this element in the genus Drosophila have suggested that R2 elements are absent from many species of this genus, particularly those species from the subgenus Drosophila. In this report, we present an extensive study of the distribution and evolution of R2 elements in Drosophila. A PCR survey of 59 species from 23 species groups of the two major Drosophila subgenera found that R2 elements are present in all but two species of the melanogaster species subgroup. Phylogenetic analysis based on partial nucleotide sequences of R2 elements from 23 species demonstrates that the relationships of R2 elements are congruent with those of the Drosophila species phylogeny, suggesting that these elements have been vertically inherited since the divergence of this genus some 60 MYA. Sequence variation between different copies of R2 elements within each species was less than 0.16%, indicating that these elements are undergoing concerted evolution similar to that of the 28S genes. Several properties of the R2 sequences suggest that these elements depend on retrotransposition in addition to simple recombination to remain within the rDNA locus: the rates of synonymous substitutions averaged 4.8 times the rate of replacement substitutions, 82 of 83 R2 copies partially sequenced contained intact open reading frames, and, finally, length variation associated with the poly(A) 3' tails indicated that many R2 copies are the direct result of retrotransposition.  相似文献   

13.
Strains of "Achromobacter groups B and E" were examined for cellular fatty acid (CFA) composition to evaluate their chemical relatedness to known bacterial species and groups. The CFAs were liberated from whole cells by base hydrolysis, methylated, and analyzed by capillary gas-liquid chromatography. The CFA profiles of the two groups were identical and were distinct from CFA profiles of all other bacteria we have previously tested. These data provide support for results from whole-cell protein pattern analysis and DNA-DNA and rRNA-DNA hybridization studies, which show that "Achromobacter groups B and E" are biotypes of a single new genus and species.  相似文献   

14.
We report on an evaluation of the systematic position of the tick Anocentor nitens (Neumann), examining particularly whether Anocentor should be regarded as a subgenus of Dermacentor or as a separate genus. Twelve species of Ixodidae were analyzed phenetically by using 24 characters of adult ticks. A phenogram indicated 3 clusters, with Anocentor more closely related to Rhipicephalus than to Dermacentor. The results of this study endorse the validity of the monotypic genus Anocentor.  相似文献   

15.
The study revealed the existence of differences between various representatives of the genus Neisseria gonorrhoeae, as well as intraspecific variations of N.gonorrhoeae by the spectrum of biological characteristics, including antilusozyme and anticomplement activity and resistance to the bactericidal action of blood serum and to the preparation of human leukocyte interferon. In contrast to other Neisseria species, all N.gonorrhoeae were characterized by a high level of anticomplement activity and resistance to the host's bactericidal systems, while a high level of antilysozyme activity, significantly exceeding that of gonococci, was found to be characteristics of other species of the genus Neisseriaceae. Within the species N.gonorrhoeae, the properties under study were associated into a single factor, closely correlated to the duration of the infectious process, which served as the basis for the development of a mathematical algorithm for the identification of persisting gonococcal strains.  相似文献   

16.
The study of the species group autumnalis in genus Neotrombicula is carried out. Composition of the group and diagnoses of species are changed, data on variability are reported. A new species, N. oculata sp. n., is described. The new species is similar to N. turkestanica Kudryashova, 1993 and differs from it by disproportionaly large eyes, a little more numerous setae of idiosoma (NDV = 66-78 against 58-69) and their lesser lengths (Dm = 41-46 against 45-49), a lesser width of scutum (AW = 71 against 76). One species, N. alexandrae Stekolnikov, 1993, is synonymized with N. delijani Kudryashova, 1977. For N. delijani and N. turkestanica new localities and new hosts are reported.  相似文献   

17.
The 17 described genomic species (DNA groups) of the genus Acinetobacter, including the type strains of the seven named species, were studied by using a multiplex PCR. The multiplex PCR assay combined two primer sets (rA1 and rA2 for recA gene target; rib1 and rib2 for 16S rDNA sequence) in a single reaction. Restriction analysis with two enzymes (Mbol and Hinfl) of the enzymatically amplified products allowed identification of all genospecies. This technique proved to be a rapid and reliable method for the identification of the Acinetobacter genomic species including the closely related DNA groups (1, 2, 3, 13). The results of this study suggest that the proposed method can be used for the identification of Acinetobacter spp. and as such may help to elucidate the ecology and clinical significance of the different species of this genus.  相似文献   

18.
Fifty-nine plants are listed, which are used by traditional healers in the central and southern parts of Somalia. For each species are listed: the botanical name with synonyms, collection number, vernacular name, medicinal use, preparation of remedy and dosage. Results of a literature survey are also reported including medicinal use, substances isolated and pharmacological effects.  相似文献   

19.
To define more accurately the taxonomic position of the species of Ctenocephalides Stiles & Collins, 1930 (Siphonaptera), a morphological study of the aedeagus was conducted an all taxa of this genus. Based on some phallosome structures (hamulus, lobes, tubus interior), an identification key is constructed to complement the existing taxonomic criteria. C. orientis and C. damarensis are confirmed to specific rank.  相似文献   

20.
Ornithogenic soil is derived from the deposition of the fecal matter of various species of birds and is a major source of nutrient input in the Antarctic marine ecosystem. A significant proportion of microbiota of ornithogenic soil collected from an Adélie penguin colony in eastern Antarctica (Vestfold Hills ice-free zone) consisted of gram-negative, coccoid bacteria identified on the basis of their phospholipid ester-linked fatty acid and lipid class profiles as Psychrobacter strains. Phenotypic, genotypic, and 16S ribosomal DNA phylogenetic analyses revealed that the Antarctic psychrobacters belonged to three distinct groups. Comparisons with Psychrobacter immobilis and Moraxella phenylpyruvica reference cultures isolated from fish, seawater, poultry, and human clinical specimens revealed the relationships of these groups within the genus Psychrobacter. Two of the groups represent the following two novel species: Psychrobacter urativorans sp. nov. (type strain, strain ACAM 534) and Psychrobacter frigidicola sp. nov. (type strain, strain ACAM 304). The third group of strains included members of the previously described species P. immobilis (Juni and Heym 1986). In addition, M. phenylpyruvica (B?vre and Henriksen 1967) is renamed Psychrobacter phenylpyruvicus comb. nov. (type strain, strain ACAM 535) on the basis of 16S ribosomal DNA phylogenetic data. In general, the genus Psychrobacter could be differentiated from the related genera Moraxella and Acinetobacter by the fact that the members of the genus Psychrobacter are psychrotolerant or psychrophilic and halotolerant, which reflects the ubiquitous distribution of the genus in both marine and terrestrial environments. On the basis of the results of this and previous studies, the genus Psychrobacter is the predominant genus in ornithogenic soils in Antarctica and is diverse.  相似文献   

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