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961.
J M Gao  X Yang  C Y Wang  J K Liu 《Fitoterapia》2001,72(8):858-864
A new C(18)-phytosphingosine ceramide containing non-hydroxy fatty acid, armillaramide (1), has been isolated together with ergosterol peroxide from the fruiting bodies of the basidiomycete Armillaria mellea. Its structure was established as (2S,3S,4R)-2-hexadecanoylamino-octadecane-1,3,4-triol by spectroscopic and chemical methods.  相似文献   
962.
We assessed clonal variation in morphological variables, mineral nutrition, root growth capacity, net photosynthesis, tannin distribution, and cuticle and epicuticular wax features within four families of white spruce (Picea glauca (Moench) Voss). Seeds were collected from four families obtained through controlled crosses among selected genotypes. For each family, plants were produced either from seeds (zygotic) or by somatic embryogenesis (clones). Each family was therefore represented by its zygotic seedlings and three clones. Within a family and under similar growth conditions, several clones differed significantly from the zygotic seedlings in height, root-collar diameter, needle dry mass, branch density, shoot dry mass, root dry mass, and length of needles. Branch density (number of first-order branches per cm height) of zygotic seedlings and clones varied from 0.8 to 1.4 branches cm(-1) and from 0.6 to 1.3 branches cm(-1), respectively. Mean needle length of zygotic seedlings and clones ranged from 11 to 14 mm and from 11 to 17 mm, respectively. For many variables (height, dry mass of new roots, needle dry mass and branch density), differences among clones were significantly greater than differences among zygotic seedlings within a family. Tannins were more abundant in needles of clones than in needles of zygotic seedlings. In some clones, tannins occurred as a ribbon along the central vacuole, whereas in others they appeared as aggregates dispersed in the vacuole. Within a family, N, P and K showed considerable variations in their use efficiency. Interclonal variations were observed in root growth potential and net photosynthesis. Variations in growth and physiology reflect genetically determined differences among clones within a family.  相似文献   
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The objective of this study was to evaluate the pharmacokinetic properties and adverse effect profile of single‐dose oral bosentan, a dual endothelin receptor antagonist, in healthy cats. Pharmacokinetic parameters were determined following a single mean ± SD oral dose of 3.2 ± 0.6 mg/kg of bosentan in 6 adult cats. Blood was collected for quantification of bosentan via high‐performance liquid chromatography with ultraviolet detection. Blood and urine were evaluated for CBC, plasma biochemical profile, and urinalysis, and repeat physical examinations were performed to evaluate for adverse effects. The mean terminal half‐life of bosentan was 20.4 ± 17.2 h. The mean peak plasma concentration was 0.49 ± 0.24 g/mL, and the mean time to maximum plasma concentration was 6.8 ± 8.6 h. The area under the curve was 5.14 ± 3.81 h·μg/mL. Oral bosentan tablets were absorbed in cats, and no clinically important adverse events were noted. Further evaluation of repeat dosing, investigation into the in vivo efficacy of decreasing endothelin‐1 concentrations in cats, as well as safety in conjunction with other medications is warranted.  相似文献   
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Summary

Leaf fragments of fig (Ficus carica L. ‘Masui Dauphine’) regenerated from in vitro shoot culture were excised and inoculated on MS medium supplemented with different combinations of 2, 4-D, TDZ, and 0.5 mM phloroglucinol. Addition of 2, 4-D induced root formation directly on the explant, and the presence of phloroglucinol significantly increased root formation. When a combination of 2, 4-D and TDZ was added to MS medium containing phloroglucinol, the explants started to produce adventitious buds at the edges. The addition of phloroglucinol was effective in inducing adventitious bud formation. Excised shoots were rooted successfully in MS medium that was either hormone free or supplemented with 1.0 mg l–1 indolebutyric acid. Regenerated plantlets were successfully established in soil after a short period of acclimatization. This is the first protocol of organogenesis and plant regeneration from vegetative organs of Ficus carica L.  相似文献   
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