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Objective To measure changes to the perineal bare area, local tissue reaction and healing responses of young sheep, following intradermal administration of cetrimide and polyvinylpyrrolidone (PVP), with and without ethanol, to the breech and tail. Method A needle‐less injector was used to deposit formulations containing 40 g/L cetrimide and 30 g/L PVP (group 2) or 20 g/L cetrimide, 30 g/L PVP and 15 g/L ethanol (group 3), within the dermis of the tail and the region surrounding the perineal bare breech area of groups (N = 8) of Merino weaner sheep. The dimensions of the perineal bare area (length, width and diagonal distances left and right) and tail width were recorded before and at intervals after treatment for 60 days. Observations of swelling and bruising and scab formation at the treatment sites were recorded for up to 35 days after treatment. Rectal temperatures were monitored for up to 35 days after treatment and bodyweight for up to 60 days after treatment. An untreated control group (group 1) was included. Results Comparison of day ‐3 and day 35 measurement data showed that both treated groups had significantly (P < 0.05) wider breech bare areas compared to the untreated controls and that group 2 sheep had significantly (P < 0.05) longer breech bare areas compared to group 3 sheep or to the untreated controls, which were not significantly different. At this time scabs were still firmly in place on many treated sheep. At day 35 there was no increase in tail bare area caused by either treatment. By day 60 there was no significant difference between the treated and control groups in either the breech or tail regions indicating that the changes present at day 35, were not permanent. Mean weight gain in the groups throughout the 60‐day interval was unaffected by treatment. Intradermal treatment was associated with a significant elevation in body temperature. This effect lasted for 3 days and was associated with signs of discomfort and depressed appearance in at least some of the treated sheep. Bruising was mild to severe in all treated sheep within two days of treatment but was not evident in any sheep by day 21. Mild to moderate swelling was also associated with treatment but was not uniform across sheep in the groups. The tail of one sheep was severely swollen for several days. Swelling remained obvious in most treated sheep until day 14 but was not present at day 21. Conclusion Under the conditions of this study intradermal injection of cetrimide had no permanent effect on bare area measurements on the breech or the amount of wool‐bearing skin on the tail. It also caused signs of discomfort and pain that raise welfare concerns.  相似文献   
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The structure of ferrihydrite, a nanocrystalline material   总被引:2,自引:0,他引:2  
Despite the ubiquity of ferrihydrite in natural sediments and its importance as an industrial sorbent, the nanocrystallinity of this iron oxyhydroxide has hampered accurate structure determination by traditional methods that rely on long-range order. We uncovered the atomic arrangement by real-space modeling of the pair distribution function (PDF) derived from direct Fourier transformation of the total x-ray scattering. The PDF for ferrihydrite synthesized with the use of different routes is consistent with a single phase (hexagonal space group P6(3)mc; a = approximately 5.95 angstroms, c = approximately 9.06 angstroms). In its ideal form, this structure contains 20% tetrahedrally and 80% octahedrally coordinated iron and has a basic structural motif closely related to the Baker-Figgis delta-Keggin cluster. Real-space fitting indicates structural relaxation with decreasing particle size and also suggests that second-order effects such as internal strain, stacking faults, and particle shape contribute to the PDFs.  相似文献   
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Olive fruits are seriously deteriorated by pre and postharvest damage due to the attack of insects, such as Bactrocera olaea, which strongly alters the quality of olives. Defence response in olive fruits injured both by pathogens and by mechanical damages has been associated with the enzyme β-glucosidase, which specifically hydrolyses oleuropein, producing highly reactive aldehyde molecules. In situ detection of ~-glucosidase activity in olive fruit tissues following injury, which simulates Bactrocera oleae punctures, is reported. The assay was performed in two cultivars showing different degrees of susceptibilities to fly infestation. In both cultivars, the histochemical assay for β-glucosidase showed that within 20 min after the injury, a strong ~-glucosidase activity could be observed in the damaged tissues. Thereafter a progressive enzyme inactivation occurred starting from tissues around the boundary of the injury with decrease of the enzyme activity and stopped after 3 h. Whereas the mass of active cells reached a distance of (300±50) μm from the edge of the injury. Biochemical analyses showed that in extracts of the injured fruit, β-glucosidase activity rapidly increased within 20 min from injury, thereafter decreasing and reaching values comparable with those in intact fruits. Following puncture, the oleuropein contents did not change significantly in the high susceptibility cultivar, whereas it rapidly decreased in the cultivar showing low susceptibility. The results strongly suggest that olive fruits susceptible towards fly infestation could be related to the ability of the oleuropein-degrading-β-glucosidase to produce the highly reactive molecules in the damaged tissues. As a consequence of puncture, high level of peroxidase activity was detected. This feature also suggested that this enzyme could play a key role in the defence response against insect injuries.  相似文献   
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AIM: To investigate a possible interaction between lolitrem B and ergovaline by comparing the incidence and severity of ryegrass staggers in sheep grazing ryegrass (Lolium perenne) containing lolitrem B or ryegrass containing both lolitrem B and ergovaline.

METHODS: Ninety lambs, aged approximately 6 months, were grazed on plots of perennial ryegrass infected with either AR98 endophyte (containing lolitrem B), standard endophyte (containing lolitrem B and ergovaline) or no endophyte, for up to 42 days from 2 February 2010. Ten lambs were grazed on three replicate plots per cultivar. Herbage samples were collected for alkaloid analysis and lambs were scored for ryegrass staggers (scores from 0–5) weekly during the study. Any animal which was scored ≥4 was removed from the study.

RESULTS: Concentrations of lolitrem B did not differ between AR98 and standard endophyte-infected pastures during the study period (p=0.26), and ergovaline was present only in standard endophyte pastures. Ryegrass staggers was observed in sheep grazing both the AR98 and standard endophyte plots, with median scores increasing in the third week of the study. Prior to the end of the 42-day grazing period, 22 and 17 animals were removed from the standard endophyte and AR98 plots, respectively, because their staggers scores were ≥4. The cumulative probability of lambs having scores ≥4 did not differ between animals grazing the two pasture types (p=0.41).

CONCLUSIONS AND CLINICAL RELEVANCE: There was no evidence for ergovaline increasing the severity of ryegrass staggers induced by lolitrem B. In situations where the severity of ryegrass staggers appears to be greater than that predicted on the basis of concentrations of lolitrem B, the presence of other tremorgenic alkaloids should be investigated.  相似文献   

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This study aimed to assess the effects of different cooling curves and centrifugation regimes used in cryopreservation protocols on the post‐thaw viability of Piau‐breed wild boar (Sus scrofa) sperm using in vitro assessment tests. Two centrifugations (800  g for 10 min and 2400  g for 3 min) and two cooling curves (conventional cooling using nitrogen vapour – freezing 1 and automated cooling using a programmed freezing machine – freezing 2) were tested. Therefore, the treatments were divided into M3 – centrifugation at 2400  g for 3 min and freezing 2; M10 – centrifugation at 800  g for 10 min and freezing 2; R3 – centrifugation at 2400  g for 3 min and freezing 1; and R10 – centrifugation at 800  g for 10 min and freezing 1. No significant differences (p > 0.05) between treatments occurred post‐thawing regarding the total sperm motility means recorded. The mean values of the different treatments were not different from each other regarding the supravital staining (SV), hypo‐osmotic test (HO), sperm–egg binding assay or sperm morphology. This study showed that both the cooling curve and the centrifugation regime affected the quality of post‐thaw sperm, and centrifugation for shorter times and cooling curves using automated cooling are the most suitable for minimizing sperm injury.  相似文献   
17.
Parasites from raw fish can lead to a wide range of clinical manifestations and can be challenging to treat in pregnancy as result of medication exposure of the foetus. We surveyed obstetrician‐gynecologists (ob‐gyns) in the U.S. to determine their knowledge about the consumption of raw fish during pregnancy. In March 2007, a questionnaire was mailed to members of the American College of Obstetricians and Gynecologists (ACOG) randomly selected to represent all members. Non‐responding physicians were sent two additional mailings. Of the 606 ACOG members surveyed, 305 (50%) responded. Most (82%) respondents indicated that eating raw fish is not safe during pregnancy. However, few (19%) knew that thorough freezing kills parasites in fish. Nearly all (94%) respondents thought that parasitic infections can be more challenging to treat in pregnancy. U.S. ob‐gyns believe that eating raw fish during pregnancy is not safe; most would benefit from information about how to prevent infection and about treatment.  相似文献   
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