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1.
Helminth parasites were identified in a natural population of primates at Polonnaruwa, Sri Lanka. Five fatally wounded or recently deceased toque macaques (Macaca sinica) and three langurs (Presbytis senex andP. entellus) were autopsied. The following nematodes were found:Oesophagostomum aculeatum (Chabertiidae),Streptopharagus pigmentata (Spirocercidae),Physaloptera sp. (Spiruridae),Enterobius vermicularis (Oxyuridae), andTrichuris trichiura (Trichuridae). One cestode,Hymenolepis was also recovered fromP. entellus. Among fresh faecal samples of 210M. sinica, worm eggs ofOesophagostomum andStrongyloides were most abundant, followed byTrichostrongylus. Trichuris andStreptopharagus eggs were found occasionally.  相似文献   

2.
Recent discovery of humic acid (HA) in the free-living, brown algaPilayella littoralis has prompted a search for HA in other live plants. Marine algaeCodium fragile andMonostoma oxyspermum (greens),Chondrus crispus,Palmaria palmata andPolysiphonia lanosa (reds),Ascophyllum nodosum, Fucus vesiculosus andLaminaria saccharina (browns) andZostera marina (marine angiosperm) were investigated for their HA content. Only the brown algae and the marine angiosperm contained HA, which was extracted by a standard procedure augmented with necessary removal of alginic acid (where applicable). The isolated products were identified as HA by comparison of their analytical data, uv-visible, FTIR,1H NMR spectra and morphologies with those of authentic HA isolated from municipal compost.Authors for correspondence  相似文献   

3.
Studies on the vertical distribution of marine fungi in aRhizophora apiculata mangrove stand in Morib, Selangor were carried out in June 1993 and June to November 1997. Prop roots, subterranean roots and overhanging branches ofR. apiculata were collected from three intertidal levels namely upper (high water mark), middle and lower. Fifty-three species were recorded including 39 ascomycetes, 13 deuteromycetes and one basidiomycete. The most common fungi wereHalocyphina villosa (frequency occurrence 21%),Kallichroma tethys (20%),Lulworthia grandispora (18%),Leptosphaeria australiensis (16%),Julella avicenniae (15%) andMassarina ramunculicola (13%). The fungi were found to be vertically zoned, some were limited to the upper level such asPyrenographa xylographoides, Julella avicenniae andAigialus grandis or lower level such asTrichocladium achrasporum andT. alopallonellum, while only five species showed a broader distribution, being present at all levels:Leptosphaeria australiensis, Halocyphina villosa, Cryptovalsa sp.,Lulworthia grandispora andLulworthia sp. The greatest diversity of marine fungi were collected from the middle level with a Shannon Diversity Index of 5.9 while the Jaccard Similarity Index of 2.25 indicated that the upper and middle levels were the most similar in terms of species composition. Fungi with certain characteristics were also limited to particular levels, for example, carbonaceous and superficial ascomata were confined above mean tide while membranous walls and immersed ascomata were common below mean tide level.  相似文献   

4.
Summary Two aerobic mesophilic species of a new genus belonging to the familyActinoplanaceae are described under the nameDactylosporangium (D. aurantiacum strainD/748 type species andD. thailandensis strainD/449). The new genus is characterized by the production of finger shaped sporangia emerging directly from the vegetative mycelium.The motile sporangiospores, three to four in number are arranged in a single straight row inside the sporangium.The genusActinoplanes of the familyActinoplanaceae was described in 1950 byCouch and is characterized by the bacteria-like, flagellated spores formed in sporangia. Other members of the familyActinoplanaceae have been studied byKarling (1954),Rothwell (1957) andCross et al. (1963) in the United States, byGaertner (1955) in Germany, byVan Brummelen andWent (1957) in Holland, byNonomura andOhara (1960) in Japan, byTaig et al. (1962),Tsyganov et al. (1963), andKoniev et al. (1965) in Russia. Except for the organisms studied byKarling and byRothwell, which undoubtedly belonged to theActinoplanes but were not studied in pure culture, the organisms studied by most of the other authors belonged to the genusStreptosporangium.Three new genera having motile spores were described more recently:Ampullariella andSpirillospora described byCouch (1963, 1964), andPlanomonospora byThiemann et al. (1967b).  相似文献   

5.
The sieve-element plastids of members of several genera in theBuxaceae (Buxus, Pachysandra andSarcococca) were found to be of the specific subtype PVI, which contains a central globular protein crystal.Simmondsia (Simmondsiaceae) andDaphniphyllum (Daphniphyllaceae), on the other hand, were found to contain S-type sieve-element plastids. The occurrence of the highly restricted PVI plastids in theBuxaceae mitigates against a close relationship between theBuxaceae andSimmondsia, Daphniphyllum andEuphorbiaceae. Exine sculpturing of theBuxaceae andSimmondsiaceae also shows no close similarities. Both of these EM characters are discussed in connection with other available data and with respect to earlier systematic treatment of these families.  相似文献   

6.
A system for nomenclature of the various homologues of the bacteriochlorophyllsc(1),d(2), ande(3) is presented.  相似文献   

7.
Physiological and biochemical properties were tested in 45 isolates ofAspergillus egyptiacus (16 isolates),Emericella nidulans (16) andAspergillus versicolor (13). The three fungal species exhibited common and similar features. The big similarity betweenA. egyptiacus andE. nidulans was greater than betweenA. egyptiacus andA. versicolor. It included the inability to produce base either from sodium citrate or lactic acid media, growth at 45 °C (thermophilicity), and production of very similar pigmentations onAspergillus flavus andparasiticus agar.A. egyptiacus is therefore better placed in theAspergillus nidulans-Emericella assemblage.  相似文献   

8.
A total of 1,302 parasitoids representing 8 species and 4 families were recovered from 9,818 fruit fly host fruits sampled. The most common parasitoid species wasDiachasmimorpha longicaudata (Ashmead). Average percent parasitism ranged between 0.44 and 29.23%. Parasitoid emergence data indicate thatAnastrepha ludens (Loew),A. obliqua (Sein),A. serpentina (Wiedeman),A. striata (Schiner) andToxotrypana curvicauda (Gerstaecker) were subject to parasitism. We provide information on the population fluctuation ofAnastrepha ludens, A. obliqua, A. serpentina, A. distincta (Greene),A. striata, A. fraterculus (Wiedeman),A. chiclayae (Greene),A. montei (Costa Lima),A. leptozona (Hendel) andA. tripunctata (Wulp).Anastrepha ludens andA. obliqua were the most common species, representing 95.3% of all fruit fly species caught in McPhail traps.   相似文献   

9.
The floristic characteristics, age structure and survival modes of Tertiary-relic deciduous forests were analyzed at 1600 m on Mt. Emei (3099 m), Sichuan, China. Three plots were selected to represent typical topographies: Plot 1 at 1620 m on a scree slope, Plot 2 at 1640 m on a slope with moderately rocky soils, and Plot 3 at 1616 m on a gentle slope with less rocky soils. At Plot 1, on the scree slope, the forest was rich in species and dominated by Tertiary remnants and other deciduous trees (Davidia involucrata, Styrax hemsleyana, Cercidiphyllum japonicum var.sinense, Pterocarya hupehensis, Prunus brachypoda, Prunus padus, Tetracentron sinense andStaphylea holocarpa). The relic deciduous tree taxaDavidia, Cercidiphyllum, Tetracentron andEuptelea occupied the unstable concave slopes, where evergreen broad-leaved trees (Castanopsis platycantha andMachilus pingii) were rarely able to survive. On the relatively stable convex slopes of this plot, evergreen trees with small diameter mainly appeared in the subcanopy and shrub layers.Davidia involucrata was the dominant species in this forest. On the slope with moderately rocky soils (Plot 2), the forest was co-dominated by relicDavidia and other deciduous (Styrax andPterocarya), and evergreen trees (Castanopsis andMachilus). On the gentle slope with less rocky soils (Plot 3),Davidia trees were found only in the subcanopy and shrub layers, and the forest was dominated byMachilus, Castanopsis, Styrax andPrunus trees. Regeneration ofDavidia occurs mainly on the scree slope where landslides are most common. The age structure of theDavidia stands indicates that this species is able to survive on the unstable scree habitat due to its strong sprouting ability. The Tertiary-relic deciduous forest on the scree slope is seen to be a topographic climax forest.  相似文献   

10.
Five different genes encoding isoenzymes of aspartate aminotransferase (AAT) have been identified in the plantArabidopsis thaliana.cDNA sequences encoding three of these AAT isoenzymes,asp1(mitochondrial),asp2(cytosolic), andasp5(plastid), were manipulated into bacterial expression vectors and the recombinant proteins expressed were purified from liquid culture using conventional methods. Yields of the purified isoenzymes varied from 11.5 mg/g wet wt cells (AAT5) to 0.95 mg/g wet wt cells (AAT2), an improvement of more than 1000-fold over typical yields of native isoenzymes obtained from plant tissues of other species. Analysis of the recombinant proteins on denaturing PAGE gels indicated subunitMrs of between 44 and 45 K. Kinetic parameters (Kmandkcat) obtained for all four substrates (aspartate, α-ketoglutarate, glutamate, and oxaloacetate) were consistent with values obtained for native AAT isoenzymes from other plant species. Further characterization of the purified recombinant enzymes alongside native enzymes fromA. thalianaleaf tissue on AAT activity gels confirmed the identity ofasp1andasp2as the mitochondrial and cytosolic AAT genes but indicated thatasp5may encode an amyloplastic rather than the chloroplastic enzyme.  相似文献   

11.
Intracellular polygalacturonic acidtrans-eliminase (PATE) was purified and characterized fromKlebsiella oxytoca andYersinia enterocolitica, enterobacteria unable to macerate plant tissue. The well-studied PATE from a strain ofErwinia chrysanthemi, a phytopathogen able to macerate plant tissue and cause soft-rot disease, was included for comparison. PATE from all strains displayed endo-splitting activity with pH optima between pH 8.5 and 9.0E. chrysanthemi had three isozymes (pls at pH 9.4, 9.0, and 7.8),K. oxytoca had two isozymes (pIs at pH 5.9 and 5.3), andY. enterocolitica had one isozyme (pI at pH 5.8). Molecular weights for theKlebsiella andYersinia PATEs were 71,000 and 55,000, respectively, compared with 33,000 for theErwinia PATE. Unlike theErwinia enzyme, theKlebsiella andYersinia PATEs did not require divalent cations for activity and could not macerate plant tissue without addition of pectinmethylesterase. The polygalacturonic acid-degrading enzymes found inK. oxytoca andY. enterocolitica appear to represent a separate type of PATE enzyme. It is unlikely that these organisms are phytopathogens; however, their ability to degrade polygalacturonic acid is probably advantageous to their survival in environments containing decomposing plant residues.  相似文献   

12.
The electrophoretic patterns of 15 protein systems codified for 20 genetic loci were investigated using horizontal electrophoresis. A total of 150 blood samples, from five species of the genusCallithrix were analyzed. Polymorphic variation was observed in 10 out 20 loci analyzed. The genotypic distributions are in Hardy-Weinberg equilibrium. The average heterozygosity (H) varied from 1% to 5%, similar to those observed for other Neotropical primates. The genetic distance coefficients revealed a phylogenetic separation of these species into two groups: (1) “argentata” (C. humeralifer andC. emiliae); (2) “jacchus” (C. jacchus, C. penicillata, andC. geoffroyi). This arrangement is according to the taxonomic arrangement proposed byHershkovitz (1977),de Vivo (1988), andMittermeier et al. (1988). The results in each group are compatible with the subspecies values recorded for the Platyrrhini. These values showed that:C. humeralifer andC. emiliae are subspecies ofC. argentata;C. jacchus, C. penicillata, andC. geoffroyi are subspecies ofC. jacchus. These results also suggest thatC. j. geoffroyi is the “jacchus” group taxon, most similar genetically to the “argentata” group.  相似文献   

13.
Silicified wood collected from the Lower Miocene Nawamata Formation at two localities, Nakaya and Nigoriike, Monzen-machi, Noto Peninsula, central Japan, were identified. Among the 58 specimens there are two species of conifers and eleven species of dicotyledons:Taxodioxylon cunninghamioides (Watari) Watari andT. sequoianum (Merckl.) Gothan (both Taxodiaceae),Carya protojaponica Watari (Juglandaceae),Pterocarya rhoifolia Siebold et Zucc. (Juglandaceae),Ostrya monzenensis sp. nov. (Betulaceae),Quercus anataiensis (Watari) Watari (Fagaceae),Liquidambar hisauchii comb. nov. (Hamamelidaceae),Prunus iwatense (Watari) Takahashi et Suzuki (Rosaceae),Gleditsia paleojaponica comb. nov. (Leguminosae),Acer watarianum Takahashi et Suzuki (Aceraceae),Meliosma mio-oldhami sp. nov. (Sabiaceae),Reevesia miocenica Watari (Sterculiaceae), andFraxinus notoensis sp. nov. (Oleaceae). The fossil wood floras at the two localities are compared to the Daijima Flora, and warm-and/or cool-temperate mesic forests are suggested to occur in the Early Miocene of Monzen.  相似文献   

14.
An evaluation of the reliability of the Emotions Profile Index (EPI), primate form, was carried out using two captive species of Old World monkeys (Papio hamadryas andMacaca fuscata) and two species (?) of New World monkeys (Saimiri sciureus andS. boliviensis). Observers, some familiar with the animals and some unfamiliar, rated members of the four groups at different times. Inter-rater reliability was high for most members of all species, but only when the observers were familiar with the animals. Assessments remained stable over at least one year.  相似文献   

15.
Campylobacter,salmonella and chlamydia in free-living birds of Croatia   总被引:2,自引:0,他引:2  
Campylobacteriosis, salmonellosis and avian chlamydiosis are zoonotic diseases in which birds have been suggested to play an important role as reservoirs. We have investigated the prevalence of Campylobacter and Salmonella spp. and Chlamydophila sp. in 107 free-living birds belonging to 25 species from 13 families from Croatia in order to examine the natural infections caused by these agents. Campylobacter jejuni-like organisms were isolated from 2 of 107 free-living bird species examined (1.9%). Salmonella was isolated from 8 fresh fecal specimens from free-living bird species (7.4%). These isolates were identified as S. typhimurium in 4 (3.7%), and S. enteriditis in 4 (3.7%) free-living birds. These samples originated from feral pigeons (Columba livia domesticus; n=14; 28.6%), rook (Corvus frugilegus; n=13; 15.4%), buzzard (Buteo buteo; n=12; 16.7%), black-headed gull (Larus ridibundus; n=8; 12.5%) and tawny owl (Strix aluco; n=8; 12.5%). The presence of Chlamydophila sp. was not detected in the free-living birds examined during this study. Epidemiological aspects and possible significance of the examined birds as a source of infections for domestic animals and humans are discussed.  相似文献   

16.
17.
Two species ofPinguicula (P. submediterranea andP. mundi) are newly described from the south and east of the Iberian Peninsula. We analysed morphometric, cytogenetic, RAPD, ecological, and breeding system data to support the distinctness of these taxa.Pinguicula submediterranea andP. mundi are both hexaploid (2n = 48), a chromosome number previously not reported for the genus. Biometric, cytogenetical and molecular results distinguishP. submediterranea andP. mundi from otherPinguicula species, and from each other.Pinguicula mundi is predominantly outbreeding, whereasP. submediterranea both inbreeds and outbreeds.Pinguicula submediterranea andP. mundi appear to be isolated reproductively, although gene flow between the allopatricP. submediterranea andP. mundi is unlikely. BothP. submediterranea andP. mundi are threatened with extinction because suitable habitats are diminishing in size, or even disappearing, due to current aridity in the region.  相似文献   

18.
Schroeder MS  Janos DP 《Mycorrhiza》2005,15(3):203-216
We examined the effects of arbuscular mycorrhizas (AM), phosphorus fertilization, intraspecific density, and their interaction, on the growth, phosphorus uptake, and root morphology of three facultative mycotrophic crops (Capsicum annuum, Zea mays, and Cucurbita pepo). Plants were grown in pots with or without AM at three densities and four phosphorus availabilities for 10 weeks. AM colonization, plant weight, and shoot phosphorus concentration were measured at harvest. Root morphology was assessed for C. annuum and Z. mays. Phosphorus fertilization reduced but did not eliminate AM colonization of all species. AM, phosphorus, and density interacted significantly to modify growth of C. annuum and C. pepo such that increased density and phosphorus diminished beneficial effects of AM. Increased density reduced positive effects of AM on C. annuum and C. pepo shoot phosphorus concentrations. AM altered both Z. mays and C. annuum root morphology in ways that complemented potential phosphorus uptake by mycorrhizas, but increased density and phosphorus diminished these effects. We infer that increased density predominantly influenced plant responses by affecting whether or not carbon (photosynthate) or phosphorus limited plant growth. By exacerbating carbon limitation, high density reduced the benefit/cost ratio of mycorrhizas and minimized their effects.  相似文献   

19.
Path analysis was used to determine the importance of long-term disturbance regime and the relative importances of correlations among vegetation patterns, disturbance history, and nitrogen (N) mineralization in old-growth forests of northwestern Minnesota. Leaf biomass (estimated by allometric equations), fire history (from fire scars on Pinus resinosa trees), and N mineralization rates (estimated from incubationsin situ) were determined from sample plots dominated by
–  Betula papyrifera, Populus tremuloides, andP. grandidentata
–  a mixture ofAcer saccharumandTilia americana, or
–  Quercus borealis andOstrya virginiana.
  相似文献   

20.
Genomic DNA samples, derived from a panel of 60 chimpanzees and 45 rhesus monkeys, were digested with the restriction enzymesTaq I andBgl II and hybridized with an HLA-DQ alpha chain cDNA probe. The results were compared with the data available on a human reference panel. Use of the restriction enzymeTaq I and the DQ alpha chain probe allows the detection of fiveHLA-DQA1 and twoHLA-DQA2 gene-associated fragments within the human population. For the ChLA and RhLA systems, 3 and 7 different DQA1-associated restriction patterns were detected, respectively, while for the chimpanzee a nonpolymorphicDQA2 (DX alpha) gene-associated fragment was also observed. The equivalent of theHLA- andChLA-DQA2 genes appears to be absent in the rhesus monkey. TheChLA-DQA1 and-DQA2 gene-associated RFLP patterns are identical in man and chimpanzee, whereas such restriction site conservation is not seen in the rhesus monkey. The conclusion drawn is that the genetic organization of theHLA-DQA andChLA-DQA gene regions, and possibly some of their allelic variabilities, already existed before man and chimpanzee separated in evolution. Moreover, the particular duplication which led to the generation of theHLA- andChLA-DQA2 genes must have happened before speciation of members belonging to the superfamily Hominoidea (man, chimpanzee, etc), but probably after the separation of superfamily Cercopitecoidea (rhesus monkeys, baboons, etc.) from Hominoidea.  相似文献   

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