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211.
An intranuclear microsporidium is described from hemoblastic cells of the chinook salmon, Oncorhynchus tshawytscha. The infection is associated with an acute anemia in the fish. Up to 47% of the hemoblast nuclei were infected in anemic fish. The organisms, found only in spleen and kidney tissues, were 1–2 μm in diameter and consisted of vegetative and early sporulation forms. This microsporidium differs from known species which parasitize fish in its tissue location; however, the absence of mature spores and other life cycle stages precludes determination of its precise taxonomic identity. 相似文献
212.
W Y Mok R C Luiz?o M do S Barreto da Silva 《Applied and environmental microbiology》1982,44(3):570-575
A total of 2,886 bats captured in the Amazon Basin of Brazil were processed for the isolation of fungi. From the livers, spleens, and lungs of 155 bats (5.4%), 186 fungal isolates of the genera Candida (123 isolates), Trichosporon (26 isolates), Torulopsis (25 isolates), Kluyveromyces (11 isolates), and Geotrichum (1 isolate) were recovered. Seven known pathogenic species were present: Candida parapsilosis, C. guilliermondii, C. albicans, C. stellatoidea, C. pseudotropicalis, Trichosporon beigelii, and Torulopsis glabrata. Twenty-three culture-positive bats showed identical fungal colonization in multiple organs or mixed colonization in a single organ. The fungal isolation rates for individual bat species varied from 1 fungus per 87 bats to 3 fungi per 13 bats, and the mycoflora diversity for members of an individual fungus-bearing bat species varied from 16 fungi per 40 bats to 7 fungi per 6 bats. Of the 38 fungal species isolated, 36 had not been previously described as in vivo bat isolates. Of the 27 culture-positive bat species, 21 had not been previously described as mammalian hosts for medically or nonmedically important fungi. 相似文献
213.
Biochemical and phenotypical correction of an envelope mutant of Salmonella typhimurium 总被引:1,自引:0,他引:1
R A Pizarro G O Boselli L V Orce 《Archives internationales de physiologie et de biochimie》1984,92(5):333-337
Salmonella typhimurium DA 361 bears an env D1 mutation with the following abnormal phenotypical and biochemical characteristics: a) it autolyses at stationary phase in nutrient broth; b) it grows in chains of short rods; c) it is a poor maltose fermenter and d) it has a diphosphatidylglycerol (DPG) content twice as high than its isogenic non-lytic pair DA 362 (env D+) and LT2, of which both are derivatives. Growth of DA 361 in the presence of 400 mM ethanol leads on a 50% decrease of DPG level, thereby equalling its PG/DPG ratio with those of the control strain. Consequently, a correction on the other phenotypical and biochemical anomalies are induced since the DA 361 strain decreases its autolytic activity, ferments normally maltose and appear as rods undifferentiated from DA 362. 相似文献
214.
215.
Evidence is presented which supports the postulate that the photobilirubins IIA and IIB are diastereoisomers in which the C-3 vinyl group has cyclized intramolecularly. The evidence comes principally from proton n.m.r. spectroscopy at 400 MHz and from chemical considerations. The cyclic structures require the E-configuration at the C-4 double bond in the precursor; this is the first structural evidence for the Z leads to E isomerization in bilirubin and supports the view that the precursor (photobilirubin IA or IB) is (4E, 15Z)-bilirubin. Brief irradiation of photobilirubin II gives bilirubin, a new compound (photobilirubin III) and unchanged starting material. The various photoisomers are discussed in terms of their inter-relationships and biological fates. 相似文献
216.
J R Ashton 《BMJ (Clinical research ed.)》1983,287(6398):1001-1002
217.
S Sayama R V Iozzo G S Lazarus N M Schechter 《The Journal of biological chemistry》1987,262(14):6808-6815
The subcellular localization of human skin chymase to mast cell granules was established by immunoelectron microscopy, and binding of chymase to the area of the dermo-epidermal junction, a basement membrane, was demonstrated immunocytochemically in cryosections incubated with purified proteinase prior to immunolabeling. Because heparin and heparan sulfate proteoglycans are major constituents of mast cell granules and basement membranes, respectively, the ability of chymase to bind to glycosaminoglycans (GAG) was investigated. Among a variety of GAGs, only binding of chymase to heparin and heparan sulfate appears physiologically significant. Binding was ionic strength-dependent, involved amino groups on the proteinase, and correlated with increasing GAG sulfate content, indicating a predominantly electrostatic association. Interaction with heparin was observed in solutions containing up to 0.5 M NaCl, and interaction with heparan sulfate was observed in solutions containing up to 0.3 M NaCl. Binding of heparin did not detectably affect catalysis of peptide substrates, but may reduce accessibility of proteinase to protein substrates. Measurements among a series of serine class proteinases indicated that heparin binding was a more common property of mast cell proteinases than proteinases stored in other secretory granules. Binding of chymase to heparin is likely to have a storage as well as a structural role within the mast cell granule, whereas binding of chymase to heparan sulfate may have physiological significance after degranulation. 相似文献
218.
Sylvester J. T.; Harabin A. L.; Peake M. D.; Frank R. S. 《Journal of applied physiology》1980,49(5):820-825
219.
This review brings together and discusses the significance ofexisting information about water-soluble (small molecule) organicphosphate constituents of red blood cells in different vertebratespecies, with emphasis on 2,3 diphosphoglycerate (DPG), inositolpentaphosphate (IP5) ATP and guanosine triphosphate (GTP), compoundswhich may play an important role in respiratory physiology bymodifying the affinity of hemoglobin for oxygen. Results onthe distribution and concentration of these compounds in redcells of vertebrate animals can be summarized as follows 1)DPG High in mammals (except cats and ruminants) Absent in crocodilianssquamata and fishes. High briefly in the bird embryo absentin adult. High briefly in turtle embryo low in juvenile lowto absent in adult 2 IP5. High in birds. Absent in mammals,crocodilians squamata and fishes (with the exception of Arapaimagigas). Low in turtles 3 ATP Intermediate in mammals. High inbirds and turtles. Very high in squamata Intermediate to veryhigh in fishes. Low in crocodilians 4) GTP Very low in mammalsbirds, reptiles and amphibians (except for small pool in Ranatadpole). Low to very high in fishes. 相似文献
220.