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81.
Total phenolic content, reducing power, antioxidant and free radical scavenging activities of ethanol extracts of five mosses were determined in vitro. No correlation between the total phenolic content and antioxidant or scavenging activities was found. 相似文献
82.
Encephalitozoon intestinalis infection of sows is reported from a pig farm in Slovakia. Spores were detected by direct microscopic visualisation in the faeces of 25 out of 27 sows (92.6%). This finding was also supported serologically by the presence of specific anti-E. intestinalis antibodies and by a species-specific polymerase chain reaction (PCR). This is the first report on E. intestinalis infection of swine in Europe. 相似文献
83.
The aim of the study was to determine the relationship between the rate of cooling of eight-cell mouse embryos to the temperature of liquid nitrogen (-196 degrees C) and their developmental capacity after thawing on the basis of their ability to leave the zona pellucida ('hatching') during in vitro culturing. Eight-cell embryos were obtained from superovulated female mice and divided into three experimental and one control group. Embryos from the experimental groups were cryopreserved by the vitrification method using ethylene glycol as cryoprotectant. The vitrification protocols used in the study differed in the rate of cooling of the cryoprotectant solution. Embryos from the first group were frozen in conventional 0.25-ml plastic straws, those from the second group in pipetting 'tips', and embryos from the third group, placed in vitrification solution, were introduced dropwise directly into liquid nitrogen. The control group of embryos was cultured in vitro without freezing in a culturing medium in an environment consisting of 95% air and 5% CO2. The developmental capacity of thawed embryos was assessed on the basis of their ability to leave the zona pellucida ('hatching') after three days of in vitro culturing. In the control group 95.1% of embryos 'hatched'. A significantly higher number of embryos that 'hatched' after thawing was observed in the group introduced dropwise directly into liquid nitrogen (60.0%) compared to the group frozen in pipetting 'tips' (37.9%). The group frozen in straws yielded significantly the lowest proportion of 'hatching' embryos (8.1%). These results showed that increasing cooling rates during vitrification of embryos improved their survival. 相似文献
84.
Petterino C Bedin M Podestá G Ratto A 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2006,35(1):95-100
A 6-year-old intact female corn snake (Elaphe guttata guttata) was presented with a 3-week history of anorexia. Coelomic radiographs revealed a 9 x 4 cm soft tissue opacity suggestive of a right ovarian enlargement. The mass (9 x 5 x 4 cm) was surgically removed, and multiple smears from tissue sections were stained with Diff-Quik. Multiple tissue samples from the mass were collected and fixed in formalin. Cytologic specimens were moderately cellular and contained light pink amorphous background material. The cells were primarily spindle-shaped with moderate to marked anisocytosis and anisokaryosis. Cells sometimes were round to polygonal, and rarely were arranged in small clusters. Macrophages occasionally were observed. Histologic specimens consisted of a highly cellular mass composed of pleomorphic, spindle-shaped cells and, occasionally, round to polygonal cells arranged in irregular fascicles. The neoplastic cells were immunoreactive for cytokeratin (AE1/AE3), smooth muscle actin, and skeletal muscle actin, but did not stain for vimentin or desmin. On the basis of the morphologic and immunohistochemical results, a diagnosis of ovarian undifferentiated carcinoma was made. In this report, we describe the challenges of using immunohistochemistry to diagnose this uncommon type of tumor in reptiles. 相似文献
85.
A survey of the prevalence of anthelmintic resistant nematode populations was conducted on 32 sheep farms in the Slovak Republic. In vitro egg hatch test and larval development tests were used for the detection of resistance to benzimidazole anthelmintics and they were compared with in vivo faecal egg count reduction tests. There was agreement in the declaration of resistance between the faecal egg count reduction test and both in vitro tests. The presence of resistant populations was determined on two farms using egg hatch test. In both farms, the LD(50) values were higher than 0.1 microg TBZ/ml, indicating resistance. By using LD(99) values it might be possible to reveal relatively small proportion of resistant larvae in the population. The prevalence of benzimidazole resistance has not change on Slovak sheep farms during last decade. 相似文献
86.
A previously reported procedure for the introduction of Borrelia spirochetes into tick larvae by immersion in a suspension of spirochetes was tested on Ixodes ricinus (L.) ticks and three of the most medically important European Borrelia genomic species, B. burgdorferi sensu stricto, B. garinii and B. afzelii. The procedure was compared with "classical" infection of nymphs by feeding on infected mice. Both methods yielded comparable results (infection rate 44-65%) with the exception of B. afzelii, which produced better results using the immersion method (44%) compared with feeding on infected mice (16%). Nymphs infected by the immersion method at the larval stage were able to transmit the infection to na?ve mice as shown by serology and PCR detection of spirochetal DNA in organs. The immersion method is faster than feeding on infected mice and provides more reproducible conditions for infection. It can be exploited for studies on both pathogen transmission and Borrelia-vector interactions. 相似文献
87.
Two experimental trials were performed to elucidate the role of rodents in the life cycle of Hepatozoon species using snakes as intermediate hosts. In one trial, two ball pythons, Python regius Shaw, 1802 were force fed livers of laboratory mice previously inoculated with sporocysts of Hepatozoon ayorgbor Sloboda, Kamler, Bulantová, Votypka et Modry, 2007. Transmission was successful in these experimentally infected snakes as evidenced by the appearance of intraerythrocytic gamonts, which persisted until the end of trial, 12 months after inoculation. Developmental stages of haemogregarines were not observed in histological sections from mice. In another experimental trial, a presence of haemogregarine DNA in mice inoculated with H. ayorgbor was demonstrated by PCR in the liver, lungs and spleen. 相似文献
88.
89.
J. A. Franco P. J. Pérez-Saura J. A. Ferná Ndez M. Parra A. L. García 《The Journal of Horticultural Science and Biotechnology》2013,88(4):430-435
SummaryAn experiment investigated the effects of two rates of irrigation, one of which reflected a substantial degree of water stress, on the mineral content, free amino acid levels and incidence of blossom-end rot (BER) in tomato (Lycopersicon esculentum Mill. `Durinta'). The plants were grown in the open with drip irrigation using saline water from a well (mean ECw 5.2 dS m21). The yield per plant was higher and fewer fruit were affected by BER in the treatment involving the higher level of irrigation. The fruit of the first and fifth truss, and the leaves immediately above, were analysed for their macronutrient, micronutrient and free amino acid content. The macronutrient leaf and fruit content hardly showed any difference, only the N concentration in fruit being significantly affected in the water stressed plants, in which the levels were higher. The Ca concentration in the stylar portion of mature fruit, which is related with the incidence of BER, was not significantly affected by the level of irrigation. As regards micronutrients, only the Fe (in leaf and fruit of the first truss), Cu (in leaf of the first truss), Zn (in leaf and fruit of the first truss, and leaf of the fifth truss) and Mn (in leaf of the first truss) concentrations differed significantly. The total free amino acid leaf content was similar in both irrigation treatments. However, the total free amino acid content of fruit, significantly those of the first truss, was higher in the less irrigated treatment. The amino acids: aspartic acid (only from the first.truss), glutamic acid, proline and alanine had high concentrations in the fruit of the less irrigated plants, while the g-aminobutyric acid and phenylalanine (only from the fifth truss) concentrations were higher in fruit of the more irrigated plants. 相似文献
90.
Čermák Jan Simon Jaroslav Káňová Hana Tichá Soňa 《Urban Forestry & Urban Greening》2013,12(2):238-245
The health status of 200- to 400-year-old trees growing in an area alongside a road was described in detail on the basis of evaluation of hazard trees in urban areas and analyzed using the acoustic scanning and modified earth impedance (MEI) methods. Acoustic analysis was used to characterize tree trunks and coarse roots; MEI was used to characterize the active absorptive root surfaces (the electric impedance of soils and sapwood were also included). Several groups of trees were distinguished according to the extent of damage (slight, serious or extreme), which was easily detectable from the MEI results. It was confirmed that both methods gave similar results, which also corresponds to the detailed observations. Instrumental measurements provided additional information about trunk and root injuries, which cannot be directly observed. A combination of both methods is recommended to achieve the most reliable results. This unique approach is applicable for testing eventual threats by old ill trees for safety reasons over the landscape. 相似文献