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1.
Takeo Horiguchi 《Phycological Research》1996,44(3):143-150
A new raphidophyte flagellate is described from the river mouth of the Daintree River, north-east Australia where there are extensive mangrove forests. The organism has two distinct phases: a club-shaped motile form, and a more or less spherical benthic non-motile form. The motile cell is metabolic and possesses 10–20 chloroplasts. The chloroplasts are imbricated, somewhat reminiscent of roofing tiles. A unique structure has been found at the posterior end of the cell. It is a tubular invagination, which consists of a single membrane supported by many small flattened vesicles. In addition, the structure is surrounded by many fibril-containing vesicles. The tubular invagination is different from both the contractile vacuoles and the pusules of dinoflagellates in both behavior and structure. Based on the possession of these unique features, it is concluded that the this mangrove flagellate should be described as a new species in a new genus and the name Haramonas dimorpha Horiguchi gen. et sp. nov. is proposed. 相似文献
2.
M. Pons M. García A. Borell F. Garcia J. Egozcue M. A. Gorostiaga A. Delprat M. Mudry 《American journal of primatology》1995,37(4):325-331
Cytogenetic studies have been carried out in 39 specimens of C. apella of different origins. Three different morphologies, one affecting the long arm of chromosome 4 and two affecting pair 17, have been detected. In each case, they can be related by paracentric inversions. Heterochromatin polymorphisms affecting terminal or interstitial C+ regions have also been observed. The length of the terminal heterochromatic region in the long arms of chromosome 11 is variable in C. apella sp., in C. a. paraguayanus and absent in the C. a. nigritus specimens studied. Interstitial C + bands can be observed in the long arms of the biarmed chromosomes 4 and 6, and in the long arms of the acrocentric pairs 12, 13, 17, 18, 19, 20, and 21. Interstitial C + bands in the long arms of chromosomes 4, 12, 17, and 19 are present in all animals studied, although their size is variable, especially in the case of chromosomes 17 and 19. © 1995 Wiley-Liss, Inc. 相似文献
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A new nematode genus, Nothacrobeles, is proposed in the subfamily Acrobelinae. Four new species are described and one new combination made. The five species exhibit a progression from short-to-long, bifurcate, elaborately fringed labial probolae, the longest probolae resembling those of species of Acrobeles. 相似文献
6.
Two new propagule-farming red algae from southern Australia, Deucalion levringii (Lindauer) gen. et comb. nov. and Anisoschizus propaguli gen. et sp. nov., are described and defined largely on their development in laboratory culture. Deucalion is included in the tribe Compsothamnieae on the basis of its subapical procarp and alternate distichous branching. It differs from the other genera included in that tribe in that it produces 3-celled propagules, polysporangia, a subapical cell of the fertile axis which bears 3 pericentral cells, and an apparently post-fertilization involucre which develops from the hypogenous and sub-hypogenous cells of the fertile axis. Its gametophyte morphology has been elucidated in culture, as only sporophytes are known from the field. Gametophytes do not appear to produce propagules. Anisoschizus is provisionally included in the tribe Spermothamnieae on the basis of its subdichotomous branching, possession of a prostrate system and the production of polysporangia. It differs from the other genera of the tribe in the production of 2-celled propagules. Observations on the germination of the “monosporangia” of Mazoyerella arachnoidea and Monosporus spp. indicate that they are analagous to the propagules of Deucalion and Anisoschizus. The nature of these propagules and their role in recycling the parent plant are discussed and contrasted with true monosporangia. It is recommended that Monosporus be maintained as a form genus containing representatives from more than one tribe, as exemplified by plants from Lord Howe I. provisionally identified as M. indicus Boergesen which have both prostrate and erect, as opposed to only erect, axes. 相似文献
7.
Alan G. Brady Lawrence E. Williams Charles J. Hoff Virginia L. Parks Christian R. Abee 《Journal of medical primatology》1998,27(5):266-270
This study evaluated manual caliper measurement of fetal BPD in Saimiri through the abdomen of the dam (TBPD) for correlation with paired ultrasound measurements, prediction of delivery date, subspecies variation, prediction of pregnancy outcome, and correlation between postpartum BPD and TBPD. Regression analysis revealed a close relationship between TBPD measurements and those obtained by ultrasound (P < 0.001). TBPD for Saimiri boliviensis boliviensis increased from a mean of 14.8 ± 0.3 mm for 11 weeks prepartum to a delivery week measurement of 33.2 ± 0.2mm. Delivery-week TBPD of Saimiri boliviensis peruviensis were significantly smaller than Saimiri sciureus sciureus (P < .05). Delivery week TBPD had a correlation coefficient of 0.64 with paired post-patrum measurements. No complications were associated with the technique. Delivery date could be predicted within two weeks. TBPD is an inexpensive, safe, rapid method of approximating fetal growth during the last half of pregnancy in Saimiri. 相似文献
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The desulfurization activity of the resting cells of Gordona sp. CYKS1 was strongly depended on harvest time and the highest value when the cells had been harvested in the early growth phase (0.12 mg sulfur g–1 cell–1 h–1). For the model oil, hexadecane containing dibenzothiophene, the specific desulfurization rate decreased as the reaction proceeded. Both the specific and the volumetric desulfurization rates were not significantly affected by the aqueous-to-oil phase ratio. The diesel oils, light gas oil and a middle distillate unit feed were desulfurized at higher rates (ca. 0.34 mg sulfur g–1 cell–1 h–1) than the model oil (0.12 mg sulfur g–1 cell–1 h–1). 相似文献
10.
M. Y. Shukor M. F. Rahman Z. Suhaili N. A. Shamaan M. A. Syed 《World journal of microbiology & biotechnology》2009,25(7):1225-1234
A bacterium that was able to tolerate and reduce as high as 50 mM of sodium molybdate to molybdenum blue has been isolated
from a metal recycling ground. The isolate was tentatively identified as Serratia sp. strain Dr.Y8 based on the carbon utilization profiles using Biolog GN plates and partial 16S rDNA molecular phylogeny.
ANOVA analysis showed that isolate Dr.Y8 produced significantly higher (P < 0.05) amount of Mo-blue with 3, 5.1 and 11.3 times more molybdenum blue than previously isolated molybdenum reducers such
as Serratia
marcescens strain Dr.Y6, E. coli K12 and E. cloacae strain 48, respectively. Its molybdate reduction characteristics were studied in this work. Electron donor sources such as
sucrose, mannitol, fructose, glucose and starch supported molybdate reduction. The optimum phosphate, pH and temperature that
supported molybdate reduction were 5 mM, pH 6.0 and 37°C, respectively. The molybdenum blue produced from cellular reduction
exhibited a unique absorption spectrum with a maximum peak at 865 nm and a shoulder at 700 nm. Metal ions such as chromium,
silver, copper and mercury resulted in approximately 61, 57, 80, and 69% inhibition of the molybdenum-reducing activity at
1 mM, respectively. The reduction characteristics of strain Dr.Y8 suggest that it would be useful in future molybdenum bioremediation. 相似文献