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1.
The tools available for monitoring necrotic enteritis caused by Clostridium perfringens in broiler chickens have been limited, particularly for identifying subclinical disease. In this study, a modified enzyme-linked immunosorbent assay was used to quantify levels of specific immunoglobulin G to C. perfringens alpha-toxin in serum from broilers. We found significantly higher antibody levels in broilers with a history of subclinical necrotic enteritis compared with a zinc-bacitracin-treated group with a low level of gut lesions. Furthermore, in 4.5-week-old commercial broiler flocks, there was an association between the occurrence of C. perfringens-associated hepatitis at slaughter and the immune response to alpha-toxin. Practical solutions for defining cut-off levels for positive serum samples at individual and flock levels are proposed, and were found to be useful on a set of samples available from flocks with different histories regarding the occurrence of C. perfringens-associated disease. This serological approach seems promising as a diagnostic tool in research and disease monitoring regarding C. perfringens-associated disease.  相似文献   
2.
The in vitro exposure of rat bronchial smooth muscle to the acetylcholinesterase inhibitor soman (0-[1,1,2-trimethylpropyl]-methylphosphonofluoridate) reduced the potassium (51 mM) evoked release of 3H-acetylcholine (3H-ACh). Exposure to 1.0 and 100 microM soman for 15 min inhibited the acetylcholinesterase (AChE) activity completely and reduced the potassium evoked release by 23.1% and 34.4% respectively. In the presence of scopolamine (0.3 microM), however, there was a large enhancement (87.0%) of potassium evoked release during soman inhibited (100%) AChE-activity. Furthermore, soman (1.0 microM) did not reduce the spontaneous release of 3H-ACh. The results indicate that the presynaptic effect of soman is due to the enhanced concentration of ACh following AChE-activity inhibition in the synaptic region. This induces a stimulation of presynaptic muscarinic receptors and thereby modulation of the ACh release only during evoked release.  相似文献   
3.
The morphologic effects of androgen deprivation in the different lobes of the rat prostate were examined by light microscopic morphometry. The prostates of Wistar male rats (260-340 g) were fixed in situ by glutaraldehyde perfusion in castrated animals 1 week after gonadectomy and in intact animals. The ventral (VP), dorsal (DP), and lateral (LP) lobes as well as the coagulating gland (CG) were dissected out, weighed, and processed for light microscopy. Using stereologic methods the following parameters were estimated for each lobe: volume fraction of connective tissue, epithelium and glandular lumina, average epithelial height, average epithelial cell volume, and total number of epithelial cells. Castration leads to a 58-76% reduction of the wet weight of all prostatic lobes. The decrease of glandular tissue is greater in VP than in LP, DP, and CG. In VP and LP, there is a 39-45% reduction of the epithelial height, and this effect is less pronounced in DP and CG. For all lobes, the shrinkage of average epithelial cell volume is in the same range (25-30%). Moreover, in VP and LP, there is a 70% reduction of the total number of cells, whereas the reduction is less in DP and CG. It thus seems that the reduction of prostatic epithelial tissue mass upon castration is due to a reduction of the number of cells as well as a reduction of the volume of individual cells. VP and LP appear to be more androgen-dependent than DP and CG.  相似文献   
4.
The main aim of the present experiment was to determine whether extensive musical training facilitates pitch contour processing not only in music but also in language. We used a parametric manipulation of final notes' or words' fundamental frequency (F0), and we recorded behavioral and electrophysiological data to examine the precise time course of pitch processing. We compared professional musicians and nonmusicians. Results revealed that within both domains, musicians detected weak F0 manipulations better than nonmusicians. Moreover, F0 manipulations within both music and language elicited similar variations in brain electrical potentials, with overall shorter onset latency for musicians than for nonmusicians. Finally, the scalp distribution of an early negativity in the linguistic task varied with musical expertise, being largest over temporal sites bilaterally for musicians and largest centrally and over left temporal sites for nonmusicians. These results are taken as evidence that extensive musical training influences the perception of pitch contour in spoken language.  相似文献   
5.
6.
The aim of this study was to investigate the relationship between mucosal gizzard lesions and caecal Clostridium perfringens counts. Gross pathological changes in the gizzard and small intestine, and caecal C. perfringens counts from 1217 meat-type chickens were recorded during the course of six experiments and were statistically analysed. C. perfringens counts increased significantly (P < 0.001) with the severity of mucosal gizzard lesions. Mucosal gizzard lesions were more prevalent than necrotic enteritis. Correcting for the pen and necrotic enteritis within experiment, mucosal gizzard lesions explained 31.8% of the variation in C. perfringens counts. Mucosal gizzard lesions and age together explained 59.1% of the variation in C. perfringens counts. The mean ages of birds with moderate and severe mucosal gizzard lesions were 1.7 and 0.8 days lower than the mean age of birds with necrotic enteritis, respectively. The association between mucosal gizzard lesions and high C. perfringens counts might be of importance when attempting to improve production efficiency, health and the welfare of the chickens.  相似文献   
7.
Amalgam-related oral lichenoid reaction   总被引:3,自引:0,他引:3  
In 52 patients with oral lichen planus topographically related to amalgam restorations, the fillings were replaced by other materials in 18, 16 of whom experienced complete remission of the lesions within 1-12 months. These results are discussed in relation to the results of epicutaneous patch tests for possible allergy to a number of mercury compounds. The term "oral lichenoid reaction", is suggested to describe these lesions.  相似文献   
8.
Summary Eighteen patients with advanced solid cancer were treated with daily 5-dFUrd infusions given over 1 h on days 1–5 of a 4-week cycle. Nine patients received 3 g/m2 5-dFUrd daily and another nine patients 5 g/m2. One patient on 5 g/m2 5-dFUrd was not fully evaluable for tolerability due to early death (progressive disease) 4 weeks after the first cycle. A total of 48 cycles was given. The gastrointestinal and hematological toxicity was generally mild (grade 1–2). Central neurotoxicity (ataxia, unsteadiness, diplopia, dysarthria, sometimes confusion) was observed in 7 of 8 patients on 5 g/m2 5-dFUrd leading to premature discontinuation of treatment in 3 patients (after 2 cycles). Only 3 of the 9 patients in the 3 g/m2 group had slight signs of cerebellopathy. Typically, the reversible neurological side effects started at the end of the 2nd week of a cycle. The serum elimination kinetics of 5-dEUrd and its metabolites 5-FU and 5-dFUH2 have been investigated in the serum and showed very low intra- and interindividual variations. Peak concentrations of the 5-dFUrd at the end of the infusion approximated 500 mol/l and 1000 mol/l for the 3 g/m2 and 5 g/m2 group, respectively. The peak of the serum 5-FU was reached at the same time, the ratio 5-FU/5-dFUrd being around 10%. The elimination half-life time for 5-FU was protracted by a factor of 2–3 compared with the direct injection of 5-FU.Monthly infusion of 5-dFUrd 5 mg/m2 per day on days 1–5 lead to an unacceptable frequency and degree of neurological toxicity. Similar infusions of 5-dFUrd 3 g/m2 per day on days 1–5 were well tolerated.  相似文献   
9.
Scientific evidence suggests that a vegan diet might be associated with impaired bone health. Therefore, a cross-sectional study (n = 36 vegans, n = 36 omnivores) was used to investigate the associations of veganism with calcaneal quantitative ultrasound (QUS) measurements, along with the investigation of differences in the concentrations of nutrition- and bone-related biomarkers between vegans and omnivores. This study revealed lower levels in the QUS parameters in vegans compared to omnivores, e.g., broadband ultrasound attenuation (vegans: 111.8 ± 10.7 dB/MHz, omnivores: 118.0 ± 10.8 dB/MHz, p = 0.02). Vegans had lower levels of vitamin A, B2, lysine, zinc, selenoprotein P, n-3 fatty acids, urinary iodine, and calcium levels, while the concentrations of vitamin K1, folate, and glutamine were higher in vegans compared to omnivores. Applying a reduced rank regression, 12 out of the 28 biomarkers were identified to contribute most to bone health, i.e., lysine, urinary iodine, thyroid-stimulating hormone, selenoprotein P, vitamin A, leucine, α-klotho, n-3 fatty acids, urinary calcium/magnesium, vitamin B6, and FGF23. All QUS parameters increased across the tertiles of the pattern score. The study provides evidence of lower bone health in vegans compared to omnivores, additionally revealing a combination of nutrition-related biomarkers, which may contribute to bone health. Further studies are needed to confirm these findings.  相似文献   
10.
Decentralization may be defined as the spread of power from higher to lower levels in a hierarchy. For hospitals, decentralization is an organizational change of special importance. Decentralization in hospitals may be accomplished through decentralization to departments; more general changes in organizational structure (reduction in the number of hierarchical levels and divisionalization); and, delegation of tasks. A framework for an analysis of decentralization status in hospitals is proposed in four main points; its starting point; the need for change in decentralization status; decentralization solutions; and, the need for review before a decentralization proposal is put into practice. Positive effects of decentralization may be obtained; but, to date, empirical investigations on the impact of decentralization in hospitals are few.  相似文献   
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