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991.
992.
The in vivo Effect of Nisin on the Microflora of the Oral Cavity 总被引:1,自引:1,他引:0
SUMMARY: Saliva specimens from 2 groups of volunteers were taken immediately before and after one group had consumed 25,000 i.u. of nisin/day for 14 days, and were analysed quantitatively for total viable and nisin-resistant bacteria. No significant differences were observed between the pre- and post-test specimens from either group. 相似文献
993.
Nucleoside transport in animal cells 总被引:19,自引:0,他引:19
994.
995.
996.
Summary The effects of added silicon on the absorption and transport of manganese in perennial ryegrass (an accumulator of Si) were
determined and compared with those found in white clover (which has restricted Si uptake). The plants were grown in flowing
solution culture in two experiments with Si in the nutrient solution maintained at 0, 10 or 20 mgl−1 and Mn at 0.005 mgl−1. By the final harvests, the plants contained concentrations of both Mn and Si that were comparable to those found in field-grown
plants.
In common with other findings, white clover had very much lower concentrations of Si in both shoots and roots than did ryegrass
but there was no effect of Si treatment on the growth of either species. In both species, the concentrations of Mn were initially
greater in roots than in shoots, but values in both plant parts decreased with time and by the final harvests, were similar.
The rates of absorption of Mn by roots and its subsequent transport to shoots were also similar in both species. In contrast
to findings for other species in other studies based on conventional solution culture, there was no effect of added Si on
either absorption or transport of Mn in clover or ryegrass. It was therefore concluded that any effect of Si on the behaviour
of Mn in plants must result from changes in distribution and partitioning within leaf tissues and cells. 相似文献
997.
Linnaean names appearing in Volume 1 of Flora Nordica are typified. The main sources for types are the Linnaean Herbarium (LINN), the Clifford Herbarium (BM), the Burser Herbarium (UPS) the Iter lapponicum Herbarium in Paris (LAPP), and cited illustrations. The study forms part of the "Linnaean Plant Name Typification Project" based at the Natural History Museum (BM). Flora Nordica notes no. 10. 相似文献
998.
Juan R. González Alejandro Cáceres Tonu Esko Ivon Cuscó Marta Puig Mikel Esnaola Judith Reina Valerie Siroux Emmanuelle Bouzigon Rachel Nadif Eva Reinmaa Lili Milani Mariona Bustamante Deborah Jarvis Josep M. Antó Jordi Sunyer Florence Demenais Manolis Kogevinas Andres Metspalu Mario Cáceres Luis A. Pérez-Jurado 《American journal of human genetics》2014
999.
John Proctor K. Bartlem S.P. Carter D.A. Dare S.B. Jarvis D.R. Slingsby 《Plant Ecology & Diversity》2013,6(1):47-63
Summary The vegetation of two ultramafic sites (MK1 and MK2) at Meikle Kilrannoch are described. MK1 is dome shaped and has much weathering bedrock whilst MK2 is flatter, lacks weathering bedrock and has probably been entirely peat covered. Six vegetation Groups were recognized: I, high-level blanket bog; II and III, grass heath (with II more sedge-rich); IV, dwarf shrub heath; V and VI, debris (an open vegetation on stony skeletal soils). Vegetation maps were produced which had five mapping units: Group I, Groups II and IH combined, Group IV, Groups V and VI combined, and non-vegetated eroding peat. Three main soil types occur: peat, which underlies Group I; a complex of freely draining magnesian brown soils and imperfectly drained magnesian gleys which bear Groups II–IV; and skeletal soils, derived either from weathering bedrock (MK1 only) or ultramafic drift, which bear vegetation in Groups V or VI. The rare plants are commonest in, but not restricted to, debris vegetation on skeletal soils. The likely plant toxicity of soil magnesium at the sites is reaffirmed but it is suggested that the low plant cover in the debris is more likely to result from low nutrients or intensive frost action or both. Floristic differences between MK1 and MK2 are discussed and quantified for Lychnis alpina (which had 68000individuals on the former site and 46 on the latter) but the causes of the differences remain unexplained. 相似文献
1000.
J. McLeod Griffiss H. Schneider R. E. Mandrell G. A. Jarvis J. J. Kim B. Gibson M. A. Apicella 《Antonie van Leeuwenhoek》1987,53(6):501-507
The outer membrane glycolipids of Neisseria lack long polysaccharides and are properly termed lipooligosaccharides (LOS). A Neisseria strain makes from two to six LOS of Mr 3150–7100. Different species commonly make LOS of identical Mr and epitope content. Oligosaccharide (OS) differences account for physical heterogeneity. OS consist of a conserved triantenary basal oligosaccharide, two linear segments of (n) hexose residues that determine OS mass, and terminal sequences similar to those of glycosphyngolipids. Epitope expression is linked to physical heterogeneity and conditioned by the molecular environment of the outer membrane. Serotype epitopes are expressed on Mr-restricted LOS. LOS regulate complement activation onto the bacterial surface and, hence, immune lysis. 相似文献