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Chemical investigation of the Mediterranean sponge Sarcotragus spinosulus led to the isolation of a new hydroxylated nonaprenylhydroquinone, along with two known metabolites, hepta- and octaprenylhydroquinones. The structure of the new metabolite was assigned by extensive 1D and 2D NMR analyses and MS studies. The antileukemic effect of the three compounds towards the chronic myelogenous leukemia (CML) cells line K562 was also evaluated.  相似文献   
63.
Landscape Ecology - Plant populations in agricultural landscapes are mostly fragmented and their functional connectivity often depends on seed and pollen dispersal by animals. However, little is...  相似文献   
64.
  • ? In this paper an evaluation of the visual grading standard for softwood sawn timber was made.
  • ? In order to do so, visual grading according to EN 518 and theoretical grading according to EN 338 and EN 384 (measurements of MOE, MOR and density) were applied to lumber. Two batches of 111 and 102 French boards were graded, respectively, of Spruce (Picea excelsa) and Douglas-fir (Pseudotsuga menziesii). For the visual grading the most discriminant criterion was noted: knots, cracks, wane, etc.
  • ? Finally, the results of the two grading methods were compared, and it was shown that the visual stress grading gave quite low results for our two French species.
  •   相似文献   
    65.
    A four‐year‐old female French bulldog was presented for evaluation of acute, left‐sided peripheral vestibular syndrome. Computed tomographic (CT) examination of the head revealed the presence of air within the left cochlea and vestibule, consistent with pneumolabyrinth. This was concurrent with ipsilateral otitis media and externa. Pneumolabyrinth is an uncommon finding in humans and is most frequently due to head trauma and temporal bone fracture. This is the first report describing pneumolabyrinth in a dog, apparently of nontraumatic origin in this case.  相似文献   
    66.
    A 2-year-old dwarf rabbit was referred for right forelimb lameness of 1-week duration. Physical examination and radiographic findings were consistent with an elbow luxation. Manual reduction under anesthesia was unsuccessful in correcting the luxated joint. A surgical approach was recommended to repair the rabbit elbow luxation. Transcondylar, transradial, and transulnar tunnels were drilled from lateral to medial with 2 suture prostheses being placed, 1 from the radius to the humerus and 1 from the humerus to the ulna. Analgesia was provided and the patient was reevaluated on days 2, 7, and 14 after the procedure. The luxation was reduced and no recurrence was noted a year following the surgical procedure. Circumferential suture prostheses, recently described with no reported postoperative complications in cats, can be used successfully in rabbits as evidenced in this case report.  相似文献   
    67.
    Florida pompano perform well on soy‐based, low‐animal protein diets. These diets may be improved through the use of enzymes as a feed supplement or as pretreatment of the soy product prior to inclusion. Novel soy products produced through enzyme treatment or fermentation often have higher protein content and lower levels of indigestible carbohydrates. Two trials were conducted to evaluate the potential of enzyme supplements. The first trial evaluated the effects of carbohydrase supplementation to diets based on two different soybean meals (commodity or selectively bred meal). Pompano fed the selected soybean had significantly improved growth rates and feed efficiency, while enzymatic supplementation had no significant effect on fish performance. However, enzyme supplementation increased phosphorus and energy retention when added to diets based on commodity soybean meal. Carbohydrase supplementation improved dry matter digestibility in commodity soy‐based diets but had no significant effect on selected soybean‐based diets. The second growth trial consisted of an increasing inclusion of an enzymatically treated soybean meal product (NutriVance). Results indicate that NutriVance can replace the totality of commodity soybean without impacting fish performance. Digestibility of the commodity soy, NutriVance, and a fermented soybean meal (Pepsoygen) was also evaluated, with no detectable difference in digestibility values.  相似文献   
    68.
    69.
    Foliage growth, mass- and area-based leaf nitrogen concentrations (Nm and N a) and specific leaf area (SLA) were surveyed during a complete vegetation cycle for two co-occurring savanna tree species: Crossopteryx febrifuga (Afzel. ex G. Don) Benth. and Cussonia arborea A. Rich. The study was conducted in the natural reserve of Lamto, Ivory Coast, on isolated and clumped trees. Leaf flush occurred before the beginning of the rainy season. Maximum leaf area index (LAI), computed on a projected canopy basis for individual trees, was similar (mean of about 4) for both species. Seasonal courses of the ratio of actual to maximum LAI were similar for individuals of the same species, but differed between species. For C. febrifuga, clumped trees reached their maximum LAI before isolated trees. The LAI of C. arborea trees did not differ between clumped and isolated individuals, but maximum LAI was reached about 2 months later than for C. febrifuga. Leaf fall was associated with decreasing soil water content for C. arborea. For C. febrifuga, leaf fall started before the end of the rainy period and was independent of changes in soil water content. These features lead to a partial niche separation in time for light resource acquisition between the two species. Although Nm, N a and SLA decreased with time, SLA and N a decreased later in the vegetation cycle for C. arborea than for C. febrifuga. For both species, N a decreased and SLA increased with decreasing leaf irradiance within the canopy, although effects of light on leaf characteristics did not differ between isolated and clumped trees. Given relationships between N a and photosynthetic capacities previously reported for these species, our results show that C. arborea exhibits higher photosynthetic capacity than C. febrifuga during most of the vegetation cycle and at all irradiances.  相似文献   
    70.
    For the very first time, a classical flow visualization technique was used to capture the fluid motion in traditional flutes and coupes poured with champagne. It was found that glasses engraved around their axis of symmetry produce a rising gas column along the vertical glass axis that induces, in turn, steady state recirculating flow regions. In the case of the classical engraved champagne flute, the whole domain of the liquid phase is homogeneously mixed, whereas in the case of the engraved champagne coupe, the recirculating flow region does not occupy the whole volume in the glass. In the engraved coupe, a dead-zone of very low motion was identified, which inhibits the formation of the collar at the glass edge. Our results finally strongly suggest that the glass-shape and engravement conditions should likely have a strong impact on champagne tasting by modifying the kinetics of release of carbon dioxide molecules and aromatic volatile organic compounds from the liquid medium.  相似文献   
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