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Alabart JL Folch J Fernández-Arias A Ramón JP Garbayo A Cocero MJ 《Theriogenology》1995,44(7):1011-1026
Rasa Aragonesa ewes (n = 89) received 2 embryos on Day 6 of the estrous cycle (Day 0 = estrus) from 46 donors of the same breed that had been superovulated with FSH-p. The influence of several variables on fertility and prolificacy after transfer was studied by discriminant analysis. Our results showed that the main variables that contributed to a high fertility rate were the degree of synchrony (better outcome if donors come into estrus later than the recipients); Fluorogestone acetate (FGA) to estrus interval and interval from previous lambing in the recipients, ovulation rate of the donors and recipients (better if superior to the mean); prolificacy of recipients in the previous lambing; and difference in developmental stage of the pair of transferred embryos (better if inferior to the mean). The main variables affecting prolificacy were the ovulation rate and weight of the donors and progesterone concentrations of the recipients (better if lower than the mean); age of the donors and difference in progesterone concentrations between donors minus those of the recipients (better if higher than the mean). The percentage of ewes correctly classified into lambing or not lambing status was 73% (P < 0.001) and that of the ewes correctly classified as lambing 1 or 2 lambs was 81.8% (P < 0.001). Whether or not the criteria we have established for optimum transfer results are applicable to conditions other than our own still needs to be confirmed. 相似文献
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C Zinner M Krueger JL Reed M Kohl-Bareis H-C Holmberg B Sperlich 《Biology of sport / Institute of Sport》2016,33(1):71-76
In this study, we tested the hypothesis that breathing hyperoxic air (FinO2 = 0.40) while exercising in a hot environment exerts negative effects on the total tissue level of haemoglobin concentration (tHb); core (Tcore) and skin (Tskin) temperatures; muscle activity; heart rate; blood concentration of lactate; pH; partial pressure of oxygen (PaO2) and carbon dioxide; arterial oxygen saturation (SaO2); and perceptual responses. Ten well-trained male athletes cycled at submaximal intensity at 21°C or 33°C in randomized order: first for 20 min while breathing normal air (FinO2 = 0.21) and then 10 min with FinO2 = 0.40 (HOX). At both temperatures, SaO2 and PaO2, but not tHb, were increased by HOX. Tskin and perception of exertion and thermal discomfort were higher at 33°C than 21°C (p < 0.01), but independent of FinO2. Tcore and muscle activity were the same under all conditions (p > 0.07). Blood lactate and heart rate were higher at 33°C than 21°C. In conclusion, during 30 min of submaximal cycling at 21°C or 33°C, Tcore, Tskin and Tbody, tHb, muscle activity and ratings of perceived exertion and thermal discomfort were the same under normoxic and hyperoxic conditions. Accordingly, breathing hyperoxic air (FinO2 = 0.40) did not affect thermoregulation under these conditions. 相似文献
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Ultrastructural localization of the high molecular weight proteins associated with in vitro-assembled brain microtubules 总被引:51,自引:30,他引:21
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Microtubules isolated from brain extracts by in vitro assembly (1, 19, 23) are composed principally of two tubulins and two high molecular weight proteins (microtubule-associated proteins [MAPS] 1 and 2) (2,5,7,20). Recently, it was demonstrated that in vitro-assembled brain microtubules (neurotubules) are coated with filaments (5, 7) which are similar to the filaments attached to neurotubules in situ (4, 15, 21, 24, 25), and it was suggested that the filaments are composed of the higher molecular weight MAPs (5, 7, 12). In this study, microtubules were assembled in the presence and absence of the MAPs, and thin sections of the microtubules were examined by electron microscopy. The results show that the filaments only occur on microtubules assembled in the presence of the MAPs and it is therefore concluded that the filaments are composed of the high molecular weight MAP's. 相似文献
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Intracavernous injection of 20 μg of prostaglandin E1 (PGE1) was carried out in 130 impotent patients. The erectile response was compared to the results of arteriological investigations including nocturnal penile tumescence and rigidity monitoring (NPTR) in 59 patients. The response of 60 patients positively categorized as exclusively psychogenic or vasculogenic was also compared to the pattern of the response to 80 mg of papaverine observed in a previous study by the same authors. The PGE1 test may not discriminate psychogenic from wholly organic patients since its results are not correlated to those of NPTR. It helps for the screening of vasculogenic impotence. Lack of response or a partly rigid response is consistent with this actiology but is not specific for it. A fully response makes it unlikely. Compared to papaverine, PGE1 induces less non rigid responses in psychogenic patients (15% versus 35% with papaverine) and more fully rigid responses in vasculogenic patients (respectively 12% and 5 %). Consequently the specificity of the PGE1 test is higher but its sensitivity lower than that of papaverine so that there is no clear difference in the effectiveness of the tests. Nevertheless the PGE1 test should be preferred, because it is safer. Prolonged erections occured in only 5 patients, and all ceased spontaneously. However 4 presented severely painful erections. 相似文献
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