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61.
The non-extractable residues of the fungicide cyprodinil formed in heterotrophic cell suspension cultures of wheat were studied by application of [2-pyrimidyl-14C] or [2-pyrimidyl-13C]cyprodinil. The main objective was to examine whether solid-state and liquid 13C NMR spectroscopy can be used to examine plant bound residues of pesticides. For 14C experiments, wheat suspensions grown on glucose as carbon source were treated with 10 mg litre(-1) of 14C-cyprodinil. After incubation for 12 days, 20% of applied 14C was detected as non-extractable residues. The cell debris were treated with 0.1 M HCl (reflux), 1.0 M HCl (reflux), buffer, or 2 M NaOH (50 degrees C); Bj?rkman lignin and acidolysis lignin fractions were also prepared from the debris. Radioactivity liberated and solubilized by these procedures was examined by thin-layer chromatography and high-performance liquid chromatography. The results showed that cyprodinil and primary metabolites contributed to the fungicide's bound residues. Most of the residues (12% of applied 14C) remained associated with polar or polymeric/oligomeric endogenous cell materials in a stable manner. For the study with 13C-cyprodinil, wheat suspensions were cultivated on 13C-depleted glucose for four growth cycles, resulting in maximum 13C depletion of the natural cell components to about 0.10%. During the fourth cycle, 13C-labelled cyprodinil was applied, and cells were incubated (12 days). Cell debris was prepared and examined by solid-state 13C NMR spectroscopy. Debris was then treated as described above in the 14C experiment. Solubilized fractions were analyzed by liquid 13C NMR spectroscopy. However, none of the 13C NMR spectra recorded gave utilizable or unambiguous results, and all exhibited large inconsistencies, especially concerning the data from the conventional 14C experiment. 相似文献
62.
63.
Melissa Cordero Dianne McFarlane Melanie A. Breshears Lisa M. Miller Margaret A. Miller Wendy M. Duckett 《Journal of Equine Veterinary Science》2012
The objective of this study was to determine the effect of season on the histologic and histomorphometric appearance of the normal equine pituitary gland. Pituitary glands were collected at necropsy from 121 horses throughout the year. Plasma was also collected from 59 of these horses before euthanasia. Hematoxylin and eosin stained median sagittal sections of each pituitary were evaluated and histologically graded by three pathologists. Histomorphometric analysis was performed on the same slides. Plasma α-melanocyte stimulating hormone was measured by radioimmunoassay in a subset of horses (n = 59). A total of 118 pituitary glands were included in the study after exclusions were made on the basis of the presence of pars intermedia (PI) adenomas (>5 mm). There was a positive correlation between PI hormone concentration (α-melanocyte stimulating hormone) and PI area. Pituitary gland measurements and grades from samples collected in the fall were compared with those collected in the nonfall months using t-test. The PI area, total pituitary area, and PI/total pituitary ratio were significantly greater in the fall compared with nonfall months (P < .0001, P < .01, P < .0001, respectively). Pituitary grades were also higher in the fall compared with nonfall months (P < .001). There was no seasonal difference in pars distalis or pars nervosa area. The results of this study show that the normal equine pituitary shows seasonal changes in appearance and size. These changes must be considered when using postmortem histologic evaluations in the diagnosis of pituitary pars intermedia dysfunction or for validation of antemortem diagnostic tests. 相似文献
64.
Dell M 《The Canadian veterinary journal. La revue veterinaire canadienne》2010,51(12):1405-1407
A 4-week-old male Pomeranian was presented with eyes that had remained closed since birth. Clinical examination of the orbits revealed that globes were bilaterally absent, suggesting clinical anophthalmos. Following ultrasound imaging of the orbits, a diagnosis of severe bilateral microphthalmos was made, a condition of rare occurrence with an etiology that is not fully understood. 相似文献
65.
Fijen Thijs P. M. Read Samantha F. J. Walker Melanie K. Gee Megan Nelson Warrick R. Howlett Brad G. 《Landscape Ecology》2022,37(7):1787-1799
Landscape Ecology - Landscape simplification is a main driver of insect decline, threatening crop pollination services. Changes in functional features in simplified agroecosystems may impact the... 相似文献
66.
In the mid-1970s, a new apple variety named ‘Meran’ was discovered in South Tyrol (northern Italy), which harbours the largest continuous apple growing area in Europe. The cultivar was registered for varietal protection and patented in several countries, and was declared to be a cross of the varieties ‘Golden Delicious’ and ‘Morgenduft’ (synonym ‘Rome Beauty’). The parentage of ‘Meran’ has, however, been questioned, and the present study aimed to assess the descent of this cultivar by the combined use of molecular genetic and bioinformatic tools. Five accessions of ‘Meran’ were collected from three different European germplasm collections and analysed at 14 variable microsatellite DNA loci. Subsequently, computer software was used to allocate the most likely parent pair from a set of cultivars representative for the apple growing area of South Tyrol in 1975. The molecular genetic data clearly excluded ‘Morgenduft’ as a gene donor to ‘Meran’ and provided strong evidence that ‘Meran’ is a cross of the cultivars ‘Golden Delicious’ and ‘Jonathan’, confirming previous assumptions based on morphological traits of the tree and fruit. 相似文献
67.
Traversa D Castagna G von Samson-Himmelstjerna G Meloni S Bartolini R Geurden T Pearce MC Woringer E Besognet B Milillo P D'Espois M 《Veterinary parasitology》2012,188(3-4):294-300
This paper reports a survey conducted in France during 2011 to evaluate the efficacy of commonly used anthelmintics against horse cyathostomins. A total of 40 farms and 1089 horses were screened for the presence of cyathostomins. All farms but one were positive, with an overall animal infection rate of 53.7%, ranging from 9% to 83% on individual farms. On 445 horses from 30 of these farms, a faecal egg count reduction test (FECRT) was performed to evaluate the efficacy of oral formulations of fenbendazole (FBZ), pyrantel embonate (PYR), ivermectin (IVM) and moxidectin (MOX). Calculation of the mean FECR and 95% confidence intervals (95% CI) around the mean was performed using bootstrap analysis. Resistance to FBZ was found on 17 of 18 farms investigated, with a mean reduction of 57% (95% CI: 38.5-71.2%). Suspected resistance for PYR was found on 6 of 30 farms, and confirmed on another 3 of 30 farms, with a mean reduction for PYR of 94.7% (95% CI: 88.9-98.5%). Reduced efficacy simultaneously of FBZ and PYR was found in 7 farms. Reduced efficacy of IVM was found in one animal on one farm and of MOX in one animal on another farm, and was combined with resistance against FBZ and/or PYR. These results indicate that single and multiple drug resistance and reduced efficacy in equine cyathostomins is present in France. Macrocylic lactones proved to be highly effective compounds against cyathostomins, with reduced efficacy for IVM and MOX in two farms only. These results extend present knowledge on the occurrence of drug resistant cyathostomins in Europe, and illustrate the necessity to use anthelmintics in appropriate worm control programmes. 相似文献
68.
Florian M. Trefz Annette Lorch Melanie Feist Carola Sauter-Louis Ingrid Lorenz 《Veterinary journal (London, England : 1997)》2013,195(3):350-356
One hundred and twenty-four calves with neonatal diarrhoea were investigated in order to assess the prevalence of hyperkalaemia and the associated clinical signs. Hyperkalaemia (potassium concentration >5.8 mmol/L) was recognized in 42 (34%) calves and was more closely associated with dehydration than with decreases in base excess or venous blood pH. In 75 calves with normal blood concentrations of D-lactate (i.e. ?3.96 mmol/L), K concentrations were moderately correlated with base excess values (r = ?0.48, P < 0.001). In contrast, no significant correlation was observed in 49 calves with elevated D-lactate. Only three hyperkalaemic calves had bradycardia and a weak positive correlation was found between heart rate and K concentrations (r = 0.22, P = 0.014). Ten of the 124 calves had cardiac arrhythmia and of these seven had hyperkalaemia indicating that cardiac arrhythmia had a low sensitivity (17%) but a high specificity (96%) as a predictor of hyperkalaemia.In a subset of 34 calves with base excess values ??5 mmol/L and D-lactate concentrations <5 mmol/L (of which 22 had hyperkalaemia), changes in posture/ability to stand could be mainly explained by elevations of K concentrations (P < 0.001) and to a lesser extent by increases in L-lactate concentrations (P = 0.024). Skeletal muscle weakness due to hyperkalaemia alongside hypovolaemia may produce a clinical picture that is similar to that in calves with marked D-lactic acidosis. However, since reductions in the strength of the palpebral reflex are closely correlated with D-lactate concentrations, a prompt palpebral reflex can assist the clinical prediction of hyperkalaemia in calves presenting with a distinct impairment in their ability to stand (specificity 99%, sensitivity 29%). 相似文献
69.
Boly M Garrido MI Gosseries O Bruno MA Boveroux P Schnakers C Massimini M Litvak V Laureys S Friston K 《Science (New York, N.Y.)》2011,332(6031):858-862
Frontoparietal cortex is involved in the explicit processing (awareness) of stimuli. Frontoparietal activation has also been found in studies of subliminal stimulus processing. We hypothesized that an impairment of top-down processes, involved in recurrent neuronal message-passing and the generation of long-latency electrophysiological responses, might provide a more reliable correlate of consciousness in severely brain-damaged patients, than frontoparietal responses. We measured effective connectivity during a mismatch negativity paradigm and found that the only significant difference between patients in a vegetative state and controls was an impairment of backward connectivity from frontal to temporal cortices. This result emphasizes the importance of top-down projections in recurrent processing that involve high-order associative cortices for conscious perception. 相似文献
70.
Respiratory function and pulmonary lesions in pigs infected with porcine reproductive and respiratory syndrome virus 总被引:1,自引:0,他引:1
Judith Wagner Annette Kneucker Elisabeth Liebler-Tenorio Vicky Fachinger Melanie Glaser Stefan Pesch Michael P. Murtaugh Petra Reinhold 《Veterinary journal (London, England : 1997)》2011,187(3):310-319
Pulmonary dysfunction was evaluated in pigs infected with porcine reproductive and respiratory syndrome virus (PRRSV, isolate VR-2332) and compared to clinical and pathological findings. Infected pigs developed fever, reduced appetite, respiratory distress and dullness at 9 days post-inoculation (dpi). Non-invasive pulmonary function tests using impulse oscillometry and rebreathing of test gases (He, CO) revealed peripheral airway obstruction, reduced lung compliance and reduced lung CO-transfer factor. PRRSV-induced pulmonary dysfunction was most marked at 9–18 dpi and was accompanied by a significantly increased respiratory rate and decreased tidal volume. Expiration was affected more than inspiration. On histopathological examination, multifocal areas of interstitial pneumonia (more severe and extensive at 10 dpi than 21 dpi) were identified as a possible structural basis for reduced lung compliance and gas exchange disturbances. 相似文献