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51.
A microenzyme-linked immunosorbent assay (dot-ELISA) was modified for making an immunodiagnosis of Fasciola hepatica infections in sheep. Sheep were alloted as follows: group I-3 controls and 4 principals, each inoculated with 500 metacercariae; group II-3 controls and 7 principals, each inoculated with 250 metacercariae; and group III-3 controls and 7 principals, each inoculated with 500 metacercariae. Blood and fecal samples were collected from each animal every 2 weeks for 16 weeks. Presence (or absence) of flukes was confirmed by fecal examinations and examination of dissected livers at necropsy of the sheep. The dot-ELISA incubations were done at ambient room temperature. Nitrocellulose disks dotted with 1 microliter (50 ng of protein) of F hepatica excretory/secretory products were placed in 96-well tissue culture plates. After nonspecific binding sites on the disks were bound with bovine serum albumin-triethanolamine-buffered saline solution, dilutions (1:2) of positive- and negative-control serum samples or experimental serum samples were placed in appropriate wells for a 30-minute incubation. Wells were washed (3 times), and 50 microliters of horseradish peroxidase conjugated rabbit anti-sheep immunoglobulin G was added to each well for a 30-minute incubation and then aspirated. Substrate solution (4-chloro-1-naphthol, methanol, triethanolamine-buffered saline solution, and H2O2; 50 microliters) was added for a 30-minute incubation and then aspirated. Disks were air dried for visualization: solid purple dot = positive sample, or no dot = negative sample.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Bare-root seedlings of Eucalyptus nitens frequently exhibit water stress after planting resulting in leaf lamina damage and reduced leaf area. Two trials examined effects of root exposure and desiccation between lifting and transplanting on post-planting water relations, leaf retention and root growth. Plants with roots exposed on a glasshouse bench initially lost water rapidly. In one trial 1 declined to around –2.0 MPa within 2.5 h, after which there was no further change with exposure up to 7.5 h. In the second trial, the initial decline in 1 was more rapid, reaching below –2.0 MPa in the first hour, before remaining stable with continuing exposure up to 4.5 h. A further decline then continued to –4.0 MPa after 7.5 h.Two days after transplanting into potting mix, day – time leaf water potentials in all desiccation treatments had declined to near –2.0 MPa. Hydraulic resistivity, measured as leaf specific resistivity two days after transplanting, increased following exposure for greater than 2.5 h, but there was no further increase between 4.5 and 7.5 h. The increase in resistivity corresponded with leaf water potential declining below –2.0 MPa during exposure.In the second trial, increasing root exposure time resulted in decreased leaf area due to lamina necrosis. Root growth, measured three weeks after planting, was also reduced. and there was also a positive curvilinear relationship between leaf area remaining at three weeks and new root growth. The results are discussed in terms of hardiness and the management of E. nitens seedlings from nursery to plantation. 相似文献
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Changes in adherence to cardiopulmonary resuscitation guidelines in a single referral center from January 2009 to June 2013 and assessment of factors contributing to the observed changes 
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下载免费PDF全文 60.
Kyle Clark Trina Bailey Paul Rist Andrea Matthews 《The Canadian veterinary journal. La revue veterinaire canadienne》2014,55(3):255-262
The frequency of claw regrowth, bony remnants, and complications in cats that underwent forelimb onychectomy using laser, scalpel, or guillotine techniques were evaluated. Eighty-seven client-owned cats were recruited from 27 veterinary clinics in the Canadian Atlantic provinces. At least 1 year after onychectomy the cats underwent a physical examination, gait analysis, and radiographic evaluation by 1 of 2 authors. There was no significant difference in the frequency of claw regrowth among the 3 methods (P = 0.283). Significantly more cats had bony remnants following guillotine onychectomy (P < 0.001). Bony remnants were significantly associated with claw regrowth (P = 0.001). Cats that underwent laser onychectomy had significantly less post-operative complications (P = 0.023). The long-term outcome was not significantly different among the 3 methods. We conclude that leaving remnants of the third phalanx in situ is associated with an increased frequency of claw regrowth. Laser onychectomy may be preferred to reduce the risk of post-operative complications, bony remnants, and claw regrowth. 相似文献