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Experiments, carried out to verify the parasitic action of Helicotylenchus digonicus on Pinus strobus and P. excelsa and their hybrid, indicate a positive host-parasite relationship. In general the consequences of nematode feeding is a reduction of seedling development similar to that induced by the absence of mycorrhizae.  相似文献   
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Fluorescein angiography without sedative or anesthetic agents was evaluated in 20 normal goats and 20 normal sheep. All of the angiographic phases were observed using 20 mg/kg fluorescein IV in both species. Fundus fluorescein angiography results revealed wide stars of Winslow in the tapetal fundus, central or marginal flow during the first part of the arterial phase, delayed filling of the focal areas in the choroid near the optic disc that often coincided with others in the disc, and lack of evidence of the 'striate area' in the tapetal fundi. In goats, the angiographic times were 6.54+/-1.25 s for the arterial phase (TA), 7.80+/-1.37 s for the arterio-venous phase (TAV), and 14.13+/-2.01 s for the venous phase (TV). I1: 1.30+/-0.30 s (time elapsing between TA and TAV), and I2: 6.20+/-1.60 s (time elapsing between TAV and TV). In sheep, times were 9.54+/-2.18 s TA, 11.73+/-2.10 s TAV, and 20.86+/-2.74 s TV. I1: 2.04+/-0.75 s and I2: 8.98+/-2.47 s, respectively. Due to the large size of the fundic vessels in sheep and goats, fluorescein angiography of the retinal vasculature can facilitate the study of the different vascular diseases in these species.  相似文献   
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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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This work aimed to evaluate the phytochemical content and to determine the antioxidant and cytotoxic activities of methanol extracts of the carob tree (Ceratonia siliqua L.) germ flour. The extracts were rich in phenolic compounds, had considerable antioxidant activity, and reduced the viability of cervical (HeLa) cancer cells. The chemical content and the biological activities of the extracts were significantly affected by gender and cultivar. Female cultivar Galhosa had the highest levels of phenolic compounds, and the highest antioxidant activity. Extracts from the hermaphrodite trees and from the female cultivars Galhosa and Costela/Canela exhibited the highest cytotoxic activity. The most abundant compound was theophylline. The phenolic content was correlated to both antioxidant and cytotoxic activities. Our findings provide new knowledge about the health implications of consuming food supplemented with carob germ flour.  相似文献   
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In this study we explored the spatial variation of Bovine tuberculosis (BTB) risk of being positive, new positive or persistently positive, as well as the risk of eliminating BTB in positive herds throughout Spain from 2006 to 2009 by means of hierarchical Bayesian models. The results of the models showed that the risk of infection (positive or new positive herds), persistence and elimination was lower in counties located in north and north-eastern of Spain, and in the Balearic and Canary islands than in the rest of the country. In some counties the risk of positivity was high during the four years of study, whereas there were others where the risk of positivity was high only in some of the years. With regard to the risk of persistence of BTB positive herds, counties located in the central, western and south-western part of the country had a higher risk in the three studied periods. This study has identified some specific areas of increased BTB risk in Spain, information that is useful for disease management.  相似文献   
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The development of the epidermis of octopus, Octopus vulgaris, throughout its life cycle was studied by conventional staining and histochemical techniques using lectins. The mantle, the arm and the two parts of the suckers: the infundibulum and the acetabulum were analysed independently. With the exception of the suckers, the general morphology of the epidermis does not vary from the first days post-hatching to adulthood. In general terms, histochemical techniques do not indicate changes in the composition of glycoconjugates of the epidermis main cells, epithelial and secretory cells. The epithelial cells of the mantle and arm show positivity for mannose (ConA+) in their apical portions, indicating the presence of n-glycoproteins that, among other things, provide lubrication to the surface of the body. In the suckers, the apical surface of the infundibulum contains sulphated glycosaminoglycans of the N-acetylglucosamine type that provide adhesive properties. In addition to observing three types of mucocytes, m1 and m2 are characteristic of the mantle and arm, and m3 is found in the suckers. The paralarva epidermis is characterised by the presence of Kölliker's organs whose exact function is unknown. In this study, the absence of staining with alcian blue/periodic acid–Schiff(AB/PAS) prevents the possibility of attributing a secretory function. Nevertheless, the linkage of three lectins (WGA, LEL and GSL-I) in the fascicle of the organ suggests the presence of proteoglycans rich in N-acetylglucosamine that would mainly have a structural role.  相似文献   
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