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21.
Purpose: To describe the protocol and appearance of fluorescein angiography (FA) in normal horses. Animals: A total of 25 healthy horses aged between 5 and 15 years. Materials and Methods: The horses were sedated with 15 µg/kg detomidine and 50 µg/kg butorphanol and dilated with topical tropicamide 1%. All angiograms were recorded after intravenous bolus injection of 10 mg/kg of fluorescein sodium solution. Results: Two successive angiographic phases could be discerned: the choriopapillary phase, starting at 46.95 ± 9.48 s, and the retinal vascular phase, starting at 47.79 ± 10.38 s. The retinal vascular phase was divided in three parts: filling phase, maximum fluorescence point, and fading phase. During the filling phase, the dye progressed into the retinal vessels, obtaining maximum fluorescence at 59.79 ± 10.39 s, termed the maximum fluorescence point. The fading phase started immediately following the maximum fluorescence point. During this phase, vascular fluorescence decreased to complete reduction at 74.76 ± 9.81 s. Also, areas of delayed choroidal filling, the presence of short retinal vessels in the ventral region of the optic disc, and a particular filling of the optic disc were also observed. Conclusions: The normal angiographic sequence was described in horses. FA may be a useful method for studying the integrity of the blood–retinal barriers in horses.  相似文献   
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Superovulation protocols are designed to achieve maximum embryo yields. Nevertheless, ovarian response control and the quality of obtained embryos are still a challenge. On the other hand, to save the superovulated embryos until their subsequent use, it is usual to cryopreserve them, so it is also crucial to assess their cryotolerance. The aim of this study was to compare the efficacy of a single injection of corifollitropin alfa (FSH‐CTP) alone or supplemented with human chorionic gonadotropin (hCG) and to determine the impact of this stimulation on in vitro and in vivo development of fresh or devitrified embryos. Our outcomes showed that ovulation rate and recovered embryos were significantly increased when hCG was used. In vitro development of fresh and devitrified embryos and survival at birth were not significantly affected by superstimulation treatment. Results of this study suggest that a single injection of long‐acting FSH‐CTP supplemented with hCG can be effectively used in rabbits to elicit an increase in ovulation rate and number of recovered embryos. Furthermore, we demonstrated that hCG supplementation had no negative effects in embryo cryosurvival and development, showing similar survival rate at birth than FSH‐CTP alone group.  相似文献   
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Sixto  H.; Grau  J.M.; Alba  N.; Alia  R. 《Forestry》2005,78(1):93-104
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In this work we address two aspects of eggplant flower biology potentially involved on the efficiency of anther culture: the selection of the best floral stage to extract anthers for culture, and the effect of heterostyly in the identification of suitable buds and anthers. For 12 different accessions, we determined morphological criteria (length ranges) to identify buds and anthers enriched in vacuolate microspores and young bicellular pollen, the stages most responsive to embryogenesis induction. While these microspore/pollen stages were the most responsive when isolated and cultured in liquid medium, we observed that culture of anthers containing these stages is not the best choice. Instead, the highest response was found for younger anthers, containing mostly young and mid microspores. We analyzed eggplant anther walls and found that their particular thickness may be behind this apparent discrepancy, since they may delay the diffusion of inducing factors to the anther locule, reducing their effect over inducible microspores. Thus, the culture of younger anthers would allow for younger microspores to grow up to the inducible stages while factors are entering the locule. We also analyzed the embryogenic response of short and long-styled buds present in Cristal, a heterostylic cultivar. Our results demonstrated that each floral morph produced buds and anthers of different lengths, but equally useful for anther culture, since similar amounts of embryos were produced. The practical application of these results may improve the efficiency of anther culture not only in these cultivars, but in others also presenting thick anther walls and heterostyly.  相似文献   
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Photolysis of quinalphos, O,O-diethyl O-(quinoxalin-2-yl) phosphorothioate ( I ), in ethanolic solutions yields two products, O,O-diethyl O-(3-ethoxy-quinoxalin-2-yl) phosphorothioate ( II ) and O,O-diethyl O-(3-(1-hydroxyethyl)-quinoxalin-2-yl) phosphorothioate ( III ). Both products derive from the reaction of photo-excited quinalphos molecule with the solvent. The reactions follow first-order kinetics. A mechanism that accounts for the formation of the above mentioned products is proposed.  相似文献   
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Plant Foods for Human Nutrition - The objective is to verify if gluten-free (GF) and gluten-containing (G) breads differ in their sodium content and lipid profile. Samples of GF...  相似文献   
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Three isozyme sytems glutamate oxaloacetate transaminase (GOT), superoxide dismutase (SOD), and malic enzyme (ME) have been analysed electrophoretically to study the diversity within and between 33 faba bean (V. faba L. type minor) accessions. For comparison, two cultivars (Vesuvio and Talo) were included in the study. Further objective of this study was to classify populations into genetic similar groups. SOD and GOT showed large variation, while ME presented minor change. Principal components, hierarchical cluster, and canonical discriminant analyses produced five groups with significant differences among them. The alleles with low frequency played a significant role in the discrimination. It was concluded that more detailed investigations regarding genetic aspects of enzyme diversity are needed to support the data here reported. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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Diurnal variations in central corneal thickness (CCT) and intraocular pressure (IOP) and their relationships were studied in healthy dogs. Central corneal thickness was measured by ultrasonic pachymetry and IOP by applanation tonometry in 16 beagle dogs. Measurements were taken every 90 min over 12 h (08:00 am to 08:00 pm). The mean CCT and IOP values obtained during the sampling period were 545.6 ± 21.7 μm (range: 471 to 595 μm) and 15 ± 2.2 mmHg (range: 10 to 19 mmHg), respectively. The CCT and IOP showed statistically significant decreases at 6:30 pm and 5:00 pm, respectively (P < 0.001). Central corneal thickness and IOP values were lower in the afternoon/evening than in the morning and were positively correlated. Both findings are important for the diagnostic interpretation of IOP values in dogs.  相似文献   
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