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31.
The potential of using composting technology to remediate clayey soils with high levels of crude oil contamination was evaluated. An open air windrow comprised of flare pit soil, manure and wood chips was constructed at Olds College, Composting Technology Centre. Aeration and mixing were carried out by a skid steer loader and composting parameters were monitored for ten months. Temperature profile of this windrow gave cyclic patterns of high and low temperature recordings corresponded to the turning events. Most of the microbial metabolic activity occurred within the mesophilic temperature range and the hydrocarbon degrading microorganism populations remained high throughout the trial. Complete removal of BTEX compounds was achieved within six months and extractable carbons from C5 to C10 were reduced by 98.7% compared to the initial contaminated soil. Vegetative growth on the composted soil was also evaluated. Barley and timothy plants grown in the composted soil were compared to the control off-lease soil, contaminated soil, and other treatments of varying salinity and organic matter levels. Plant germination, survival, and biomass production was significantly better in the composted soil than in the contaminated soil. Furthermore, barley plants grown in the composted soil were more resilient than those grown in the control off-lease soil.  相似文献   
32.
We have tested the hypothesis "that the ovulation rate in homozygous carriers (BB) and noncarriers (+2) of the Booroola FecB gene would not be different if the plasma concentrations of follicle-stimulating hormone (FSH) in the two genotypes were similar." For this purpose we used two experimental animal models: 1) the hypothalamic-pituitary disconnected (HPD) ovary-intact ewe; and 2) and GnRH agonist (i.e., Deslorelin)-treated ewe. Following HPD or Deslorelin treatment, the animals had low plasma concentrations of gonadotropins and were anovulatory. In both animal models, BB and +2 ewes were treated with exogenous pregnant mares serum gonadotropin (PMSG) and varying doses of FSH to induce preovulatory follicular growth, and human chorionic gonadotropin (hCG) to induce ovulation. HPD or Deslorelin-treated animals administered with pregnant mares serum gonadotropin without FSH followed by human chorionic gonadotropin failed to ovulate. However for both animal models, the proportion of BB and +2 ewes ovulating to various doses of FSH differed such that significantly greater proportions of +2 animals ovulated relative to the BB genotype (P < 0.05). When HPD or Deslorelin-treated BB and +2 ewes were administered identical doses of FSH, the mean ovulation rate and plasma concentrations of FSH in those animals which ovulated was the same in both genotypes. These findings confirm, at least in part, the aforementioned hypothesis. The results also demonstrated that higher ovulation rates were obtained in both genotypes as the FSH dose was increased. Collectively, these findings infer that the higher mean ovulation rate in normal intact BB ewes compared to the +2 genotype is attributable to effects of the FecB gene at the level of ovarian follicular development as well as at the level of pituitary FSH release.  相似文献   
33.
Azostix-reagent-tests(R) strips (Ames, Miles, Inc., Diagnostic Division, Elkhart, IN) were used to measure blood urea nitrogen values in blood samples from 125 dogs and cats at the North Carolina State University, College of Veterinary Medicine. Results of the tests were compared with standard serum urea nitrogen results. Sensitivity, specificity, and negative predictive values were high (86.4, 90.3, and 96.5%, respectively). Positive predictive value was low, 65.5% of the dogs and cats with elevated blood urea nitrogen values were correctly classified as abnormal The test performs well when the prevalence of abnormal values is near 50%.  相似文献   
34.
A series of hydroxynaphthoquinones, all derivatives of the antitheilerial hydroxynaphthoquinone parvaquone (993C, Clexon; Wellcome) was tested for antitheilerial activity against Theileria parva (Muguga) in vitro. BW720C (buparvaquone) was 20 times more active than parvaquone. When tested in vivo BW720C cured all 13 cattle infected with T parva and all six infected with T annulata treated at a dose rate of 2.5 mg (kg bodyweight)-1 while parvaquone at 20 mg kg-1 cured nine of 10 cattle. All 16 untreated control cattle died of theileriosis.  相似文献   
35.

Objective

The effect of user experience and inflation technique on endotracheal tube cuff pressure using a feline airway simulator.

Study design

Prospective, experimental clinical study.

Methods

Participants included veterinary students at the beginning (group S1) and end (group S2) of their 2-week anaesthesia rotation and veterinary anaesthetists (group A). The feline airway simulator was designed to simulate an average size feline trachea, intubated with a 4.5 mm low-pressure, high-volume cuffed endotracheal tube, connected to a Bain breathing system with oxygen flow of 2 L minute?1. Participants inflated the on-endotracheal tube cuff by pilot balloon palpation and by instilling the minimum occlusive volume (MOV) required for loss of airway leaks during manual ventilation. Intracuff pressures were measured by manometers obscured to participants and ideally were 20–30 cm H2O. Student t, Fisher exact, and Chi-squared tests were used where appropriate to analyse data (p < 0.05).

Results

Participants were 12 students and eight anaesthetists. Measured intracuff pressures for palpation and MOV, respectively, were 19 ± 12 and 29 ± 19 cm H2O for group S1, 10 ± 5 and 20 ± 11 cm H2O for group S2 and 13 ± 6 and 29 ± 18 cm H2O for group A. All groups performed poorly at achieving intracuff pressures within the ideal range. There was no significant difference in intracuff pressures between techniques. Students administered lower (p = 0.02) intracuff pressures using palpation after their training.

Conclusions and clinical relevance

When using palpation and MOV for cuff inflation operators rarely achieved optimal intracuff pressures. Experience had no effect on this skill and, as such, a cuff manometer is recommended.  相似文献   
36.
In this study, clinical, parasitological and histopathological findings of thirteen kelp gulls (Larus dominicanus) found infected with eyeflukes in Brazil are presented. Parasites detected in the ventral conjunctival fornix were identified as Philophthalmus lachrymosus [mean intensity of infection: 16 (5–36) worms/bird]. Eleven birds (85%) presented signs of systemic disease, such as emaciation, dehydration and depressed consciousness. Conjunctival hyperemia was observed in 22 eyes (85%). Keratitis, corneal ulcers, corneal abscess and chemosis were also detected in some eyes (4–8%). Histopathologic lesions, likely due to the parasite attachment to the conjunctiva, were found in the eyes of one infected bird that died from unrelated causes. Philophthalmosis by P. lachrymosus is here reported as a clinically relevant eye disease in kelp gulls.  相似文献   
37.
BACKGROUND: Evidence suggesting that a diet high in fruits and vegetables may be beneficial to bone health has sparked interest in the potential benefit of a vegetarian diet. However, other studies have raised a question regarding the adequacy of protein in such a diet. OBJECTIVE: The aim of the present study was to take a whole foods approach in examining the effects of foods high in protein on the risk of wrist fracture (WF) in a cohort with a significant proportion consuming a meat-free diet. DESIGN: A cohort study of women who completed two lifestyle surveys 25 years apart. SUBJECTS: One thousand eight hundred and sixty-five peri- and postmenopausal women at the time of the first survey. RESULTS: There was a significant interaction between meat consumption and foods high in vegetable protein. Among vegetarians, those who consumed the least vegetable protein intake were at highest risk for fracture. However, increasing levels of plant-based high-protein foods decreased WF risk, with a 68% reduction in risk (hazard ratio (HR) = 0.32, 95% confidence interval (CI) 0.13-0.79) in the highest intake group. Among those with lowest vegetable protein consumption, increasing meat intake decreased the risk of WF, with the highest consumption decreasing risk by 80% (HR = 0.20, 95% CI 0.06-0.66). CONCLUSIONS: The finding that higher consumption frequencies of foods rich in protein were associated with reduced WF supports the importance of adequate protein for bone health. The similarity in risk reduction by vegetable protein foods compared with meat intake suggests that adequate protein intake is attainable in a vegetarian diet.  相似文献   
38.
The accepted cut‐off value for adrenal gland maximum diameter of 0.74 cm to distinguish adrenal gland enlargement in dogs regardless of body weight may not be appropriate for small to medium breed dogs. The purpose of the current retrospective study was to examine adrenal gland dimensions as a function of body weight in healthy dogs in three weight categories (< 10 kg, 10–30 kg, and > 30 kg) representing small, medium, and large breeds, respectively, to establish greater confidence in determining if adrenal gland size is abnormal. The measurements of length (sagittal plane), cranial and caudal pole thickness (sagittal and transverse planes), and caudal pole width (transverse plane) of both adrenal glands were obtained ultrasonographically in clinically healthy dogs (n = 45) with 15 dogs in each weight group. Findings support our hypothesis that adrenal gland size correlates with body weight in normal dogs, and more precise reference intervals should be created for adrenal gland size by categorizing dogs as small, medium, or large breed. The caudal pole thickness of either adrenal gland in a sagittal plane was the best dimension for evaluating adrenal gland size based on low variability, ease, and reliability in measurement.  相似文献   
39.
Type III procollagen peptide (P-3-P) is a serum marker for hepatic fibrosis in humans. The utility of a commercially available radioimmunoassay for P-3-P was evaluated in the dog. The specificity of the assay was assessed by polyacrylamide gel electrophoresis (PAGE) of canine serum and purified bovine P-3-P, followed by Western immunoblotting with rabbit aniti-P-3-P serum. The sensitivity was assessed by performing the radioimmunoassay on dilutions of sera from 22 dogs. Polyacrylamide gel electrophoresis of purified bovine P-3-P and sera from two dogs suspected of having elevated P-3-P concentrations revealed no homologous bands of staining. Western immunoblotting showed marked cross-reactivity of the high antisera concentrations with several components of the serum proteins, but none corresponding to the purified P-3-P. All tested sera from dogs had minimal competitive binding with radiolabeled P-3-P in the radioimmunoassay. Dilution curves of dog sera did not parallel either the standard curve or the dilution curve of a known test human serum. There were no statistically different P-3-P concentrations in any of the groups of dogs studied. It was concluded that currently available radioimmunoassay kits for the measurement of P-3-P in the human are not applicable in the dog. Seemingly, the structure or metabolism of canine P-3-P may vary significantly from that of the bovine or human, limiting the sensitivity and specificity of this assay in the dog.  相似文献   
40.
Abstract. Recently, there has been interest in the occurrence of bromide (Br-) in natural waters since it has been demonstrated that Br-, in association with humic substances in raw waters, is readily incorporated into haloacetic acids in the form of organically bound bromine (Br) during water chlorination. We report results of the effects of experimentally rewetting a naturally drained gully mire on the hydrochemistry of Br-, iron (Fe) and dissolved organic carbon (DOC) in the peat water. Results obtained over a three year period showed that rewetting substantially increased the concentrations of these solutes in the pore water, with peak values of 1 mg dm-3 (Br-), > 60 mg dm-3 (Fe) and > 300 mg dm-3 (DOC) detected in some samples after rewetting, compared with typical values < 0.05 mg dm-3 (Br-), < 1 mg dm-3 (Fe) and < 15 mg dm-3 (DOC) under the drained conditions. Bromide, Fe and DOC release were highly seasonal, with the largest concentrations observed in late-summer to autumn. However, whereas seasonal peak concentrations of Fe and DOC have since remained at these higher levels, seasonal peak concentrations of Br- were progressively attenuated over time, suggesting the latter phenomenon is a flush effect, with no longer-term consequences for water quality.  相似文献   
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