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31.
32.
A serological survey for antibodies to Leptospira interrograns serovar hardjo was conducted on 574 serum samples from 10 native and 4 introduced wildlife species in south-eastern Australia. The microscopic agglutination (MA) test was used, and titres to hardjo antigen were detected in 33.5% of 352 brushtailed possums (Trichosurus vulpecula) sampled in several areas of Victoria. Prevalence of reactors ranged from 14 to 66% in 4 populations examined intensively. Serovar balcanica was isolated from possums with hardjo antibodies from two different areas. Of 20 wombats Vombatus ursinus) examined in Victoria, antibodies to hardjo were found in sera from 4 and titres to Pyrogenes and Pomona serogroups were detected in another. Hardjo antibodies were demonstrated in sera from 13 of 19 rusa deer (Cervus timorensis). Negative MA test results to hardjo antigens were recorded in 55 mountain possums (T. caninus), 63 macropods (Macropus spp.), 17 water rats (Hydrmys chrysogaster), 39 fallow deer (Dama dama), 2 hog deer (Axis porcinus) and 2 water buffalo (Bubalus bubalus). No MA antibodies to any of 16 leptospiral serogroups were detected in 17 water rats tested. Kidneys were examined from 330 of these animals and focal interstitial nephritis suggestive of leptospirosis was found in kidneys of 63 of 169 T. vulpecula, 3 of 55 T. caninus, 12 of 18 V. ursinus, 6 of 22 Macropus spp., 9 of 16 H. chrysogaster, 5 of 11 C. timorensis and 3 of 39 D. dama. A statistical association between focal interstitial nephritis and MA antibodies to hardjo was found in T. vulpecula.  相似文献   
33.
Two homoeologous sets of chromosomes in pentaploidAllium neapolitanum Cyr. (Liliaceae) are recognizable by their C-bands. The banding pattern is the same for one Californian and five Yugoslavian populations, suggesting a common chromosomal origin. Predominant meiotic association of identically banded homologues indicates a genomic formula of AA AI BB, confirms an allopolyploid origin, and argues against genetically controlled pairing.  相似文献   
34.
Summary Specific detection of iota-Carrageenan (i-CAR) at the ultrastructural level has been obtained by coupling with ruthenium red (RR) — an electron microscopic stain. The i-CAR-RR complex showed electron density on carbon layers. Peritoneal macrophages were treated with the complex and after 3 h it caused the same morphological changes in macrophages as iota-Carrageenan alone. On the surfaces of macrophages, fine filamentous electron dense material — the i-CAR-RR complex — was detected.  相似文献   
35.
Lectin-binding glycoproteins in seven populations of two burrowing nematode sibling species were probed with five different biotinylated lectins on Western blots, and differences were correlated with nematode ability to parasitize citrus and to overcome citrus rootstock resistance. Banding patterns of molecular weight standards were fit best by an exponential decay function, and a predictive equation was used to estimate molecular weights (r² = 0.999). A band (131 kDa) that labeled with the lectin Concanavalin A (Con A) occurred in extracts from cuticles and egg shells of populations of Radopholus citrophilus that parasitize citrus. Wheat germ agglutin labeled a band (58 kDa) in aqueous homogenates of populations that reproduce in roots of citrus rootstock normally resistant to burrowing nematodes. The two sibling species R. citrophilus and R. similis were distinguished by a high molecular weight Con A-labeled band (608 kDa) from cuticle and egg shells. Probing blots with the lectin Limulus polyphemus agglutinin indicated that each population contained a band (12-16 kDa) specifically inhibited by the addition of 25 mM neuraminic acid, suggesting that glycoproteins with sialic acid moieties are present in burrowing nematodes.  相似文献   
36.
Hans  Kruuk  Tim  Parish 《Journal of Zoology》1982,196(1):31-39
This paper discusses the relationship between the distribution and biomass of the main prey of European badgers, Meles meles and the badgers group size, territory size and population density. The distribution of areas rich in earthworms, Lumbricus spp., is correlated with badger range size, whilst badger group size increases with the biomass of worms per badger territory and badger density increases with overall worm biomass. Regulation of badger density in an area is likely to take place through regulation of group size, in the absence of other factors such as persecution and lack of suitable sett-sites.  相似文献   
37.
The genormic organization of the multiple actin DNA sequences in the lower eukaryote Physarum polycephalum was investigated by Mendelian mapping. Actin-homologous restriction endonuclease cleavage fragments detected by DNA blotting showed length polymorphisms when different strains were compared. These length polymorphisms were used as phenotypic markers for actin sequences in the genome. The meiotic assortment of the polymorphic restriction fragments was analysed, revealing four unlinked actin loci. The data for three-of the actin loci, ardB, C and D, are consistent with a single sequence or gene at each locus. The data for the other actin locus. ardA, is consistent with multiple linked actin sequences or genes.  相似文献   
38.
Cerebral Synaptic Transmission During Anoxia Is Protected by Creatine   总被引:4,自引:3,他引:1  
Synaptic transmission in cerebral tissue fails very rapidly in the absence of oxygen; the metabolic basis for this is not known. We report here that the transmission failure in the guinea pig hippocampal slice can be delayed threefold by exposing the tissue to extracellular creatine (Cr) for 3 h. The improved survival is associated with an increase of tissue phosphocreatine (PCr) concentration. These data argue that the metabolic basis for synaptic transmission failure is a fall in tissue ATP concentrations. They also indicate a way to protect brain tissue against anoxic damage.  相似文献   
39.
The recovery of MAO-B activity after a single dose of 0.25 mg/kg s.c. (-)deprenyl was measured in rat, by following the time course of the changes in the PEA (phenyl-ethylamine)-induced hyperactivity. One hour after its administration (-)deprenyl enhanced both the PEA-induced locomotion and stereotypy, however, its effect on the latter was more marked. At 24 h and at later time-points only stereotype was enhanced. The results show that a single small dose of (-)deprenyl which selectively blocks MAO-B, causes a long-lasting inhibition of PEA metabolism, and the enzyme activity needs more than one week to restore completely.  相似文献   
40.
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