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The pharmacokinetic characteristics of APP were studied in 10 male New Zealand rabbits. An initial dose of 15,000 IU of APP per kg of weight was administered. The respective fibrinolytic activity was estimated by fibrin plates and transformed according to theoretical considerations. Knorre's criterion was used for the determination of the number of compartments. In every case the values were below 0.2 which indicates a one-compartment open model. The data were fitted to the proposed model in two steps; first the stripping method was used, afterwards the values obtained by the stripping were used as initial values for nonlinear fitting by means of nonlin programs.  相似文献   
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Beyond its role in the conversion of androgens to estrogens, the expression of aromatase could influence on the estrogenic signalling in targeted tissues. Considering the well‐defined biochemical and physiological differences between the pubococcygeus (Pcm) and bulbospongiosus (Bsm) muscles in female rabbits, it is presently hypothesized that the aromatase expression is differentially linked to the estrogen sensitivity of each muscle. To this end, serum estradiol levels and the aromatase expression, presence of ERα and ERβ and morphometry were evaluated in the Pcm and Bsm of female rabbits allocated in control, ovariectomized (OVX) and OVX treated with estradiol benzoate (OVX + EB) groups. Aromatase expression was high in the Pcm. Independently to serum estradiol, ovariectomy increased aromatase expression in the Pcm while decreased it in the Bsm. The EB treatment avoided the effect of ovariectomy only in the Pcm. The number of immunoreactive nuclei anti‐ERα and anti‐ERβ was high in the Pcm of OVX and OVX + EB rabbits, while those in the Bsm remained unchanged. The number of peripheral nuclei per fibre and the cross‐sectional area‐to‐myonucleus ratio were modified only in the Pcm. Our findings support aromatase expression in the Pcm, and Bsm of rabbits is differentially linked to estrogenic sensitivity of each muscle. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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Effects of an increased lead (Pb) content in soil on growth, photosynthesis (P N) and anatomical parameters of Plantago major L. plants grown under controlled conditions were studied. The total dry weights of plants at 500 and 2000 mg kg–1 Pb in soil were correspondingly 70% and 54% of those of control plants. A reduced leaf area and changed leaf structure caused a decrease in P N in the whole plant. The specific leaf weight (SLW) increased as compared with that of control plants. An increasing Pb content in soil caused a larger number of chloroplasts and larger sizes of protoplasts, a decrease in the chlorophyll a+b contents and a larger number of stomata per unit leaf area based both in adaxial and abaxial epidermis, as compared with control plants. However their conductance was from 40% to 50% lower than that in control plants. It was noted that the dimensions of conducting bundles decreased mainly because of the reduced xylem area. The lower functional activity and the changes at different structural levels of the photosynthetic apparatus caused a decrease in the growth rate of plants at a high Pb content in soil.  相似文献   
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Summary As initial studies showed that enzymatic saccharification of sugar cane bagasse in columns with recycling of eluate was slightly more efficient than in agitated flasks, ethanol production by fermentation of the eluates with fast-decanting yeast and recycling of the fermentate through the bagasse columns was studied. The alcohol yield from these coupled columns after 24 or 48 h was more than 10% more than that in a simultaneous saccharification and fermentation in agitated flasks at 40°.  相似文献   
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We have determined the urinary 8-hydroxydeoxyguanosine (8-OHdG) levels of eight professional cyclists during a 4-day and a 3-week stage races. Monitoring of heart rates was used to establish zones corresponding to different intensities of exercise. The urinary 8-OHdG excretion, expressed by body weight, increased significantly in the first day or the first week of each race, respectively, and did not show further increases thereafter. Maximum 8-OHdG levels were reached in parallel to longer times spent at high intensities of exercise. Urinary excretion of creatinine increased with exercise, and changes in 8-OHdG levels were not detected when corrected by creatinine excretion. Serum glutathione concentrations did not change significantly at any point during exercise. We conclude that road cycling courses with an oxidative damage to DNA, which is sustained as long as the exercise is repeated. Both adaptation of antioxidant defenses and a decreased capacity to maintain a high intensity of effort may contribute to explain the absence of progressive increases in 8-OHdG excretion. The results of this study also confirm that the correction procedure using the amount of creatinine excreted should not be used when studying effects of exercise on urinary 8-OHdG.  相似文献   
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