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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
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The generation of thrombin-like activity from rat, human, bovine and mouse prothrombin by Echis carinatus venom (ECV) treatment was compared using a partially purified system (i.e. whole ECV and isolated prothrombin). A rapid increase in coagulant activity was obtained within 0.5 to 2 min., being constant upon further incubation for 60 min. A large variation in coagulant activity of the ECV generated thrombin from the four species was found, whereas no differences were found for the amidolytic activities. The coagulant activities of the ECV generated thrombin was also low compared with the corresponding thrombin activities obtained by physiological activation. Coagulant activity of the ECV generated thrombin levelled off at increasing concentration of prothrombin in the sample as measured by the one-stage coagulation assay. By measuring amidolytic activity a linear relationship to the concentration of prothrombin was found, however. These findings indicate that ECV converts prothrombin from the four different species to a thrombin-like protein with properties distinct from -thrombin. The lack of linearity in the ECV generated clot activity with increasing concentration of prothrombin could be explained by assuming a dimerization of the thrombin like protein molecules making them less accessible to fibrinogen. The significance of these observations for the quantification of prothrombin from different species is discussed. 相似文献
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Physiologic mechanism and preoperative prediction of new-onset dysphagia after laparoscopic Nissen fundoplication 总被引:2,自引:0,他引:2
Dennis Blom M.D. Jeffrey H. Peters M.D. Tom R. DeMeester M.D. Peter F. Crookes M.D. Jeffrey A. Hagan M.D. Steven R. DeMeester M.D. Cedric Bremner M.D. 《Journal of gastrointestinal surgery》2002,6(1):22-28
The aim of this study was to determine whether preoperative physiologic factors can account for and be used to predict the
development of postoperative dysphagia after laparoscopic Nissen fundoplication. One hundred sixty-three patients with gastroesophageal
reflux disease underwent laparoscopic Nissen fundoplication with a median follow-up of 14 months (range 6 to 81 months). Preoperative
dysphagia was present in 37% (60 of 163) and was relieved in all but five patients (92%). Female sex (P = 0.01) and the presence of a stricture (P = 0.02) were the only preoperative variables associated with the presence of preoperative dysphagia. Eight percent (8 of
103) of patients without preoperative dysphagia developed new-onset dysphagia, and of these 63% (5 of 8) had a normal lower
esophageal sphincter (LES) (pressure >6 mm Hg; length >2 cm; abdominal length >1 cm). New-onset dysphagia was significantly
more common in patients with a normal LES (22% [5 of 23] vs. 4% [3 of 80], P = 001). Patients with a normal LES had almost a sixfold increase in the risk of developing dysphagia as those with an abnormal
LES (relative risk = 5.8). Only a preoperative normal LES (P = 0.02) or mean LES pressures (P = 0.04) were positively associated with the development of postoperative dysphagia. The severity of this dysphagia also showed
a strong positive trend of increasing with mean preoperative LES pressures (P = 0.07). Finally, preoperative LES pressure significantly correlated with postoperative LES pressure (r = 0.48, P = 0.01) and with mean residual LES (nadir) pressure (r = 0.33, P = 0.05) offering insight into the mechanism of this dysphagia. In conclusion, preoperative LES parameters play a role in
the development of dysphagia after laparoscopic Nissen fundoplication. Patients with a normal LES or high mean LES pressures
are at increased risk for developing this complication and should be informed of this before laparoscopic Nissen fundoplication.
Presented at the Forty-Second Annual Meeting of The Society for Surgery of the Alimentary Tract, Atlanta, Ga., May 20–23,
2001. 相似文献
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Tori Smedal Hildegunn Lygren Kjell‐Morten Myhr Rolf Moe‐Nilssen Bente Gjelsvik Olav Gjelsvik Liv Inger Strand 《Physiotherapy research international》2006,11(2):104-116
Background and Purpose . Patients with multiple sclerosis (MS) tend to have movement difficulties, and the effect of physiotherapy for this group of patients has been subjected to limited systematic research. In the present study physiotherapy based on the Bobath concept, applied to MS patients with balance and gait problems, was evaluated. The ability of different functional tests to demonstrate change was evaluated. Method . A single‐subject experimental study design with ABAA phases was used, and two patients with relapsing–remitting MS in stable phase were treated. Tests were performed 12 times, three at each phase: A (at baseline); B (during treatment); A (immediately after treatment); and A (after two months). The key feature of treatment was facilitation of postural activity and selective control of movement. Several performance and self‐report measures and interviews were used. Results . After intervention, improved balance was shown by the Berg Balance Scale (BBS) in both patients, and improved quality of gait was indicated by the Rivermead Visual Gait Assessment (RVGA). The patients also reported improved balance and gait function in the interviews and scored their condition as ‘much improved’. Gait parameters, recorded by an electronic walkway, changed, but differently in the two patients. Among the physical performance tests the BBS and the RVGA demonstrated the highest change, while no or minimal change was demonstrated by the Rivermead Mobility Index (RMI) and Ratings of Perceived Exertion (RPE). Conclusion . The findings indicate that balance and gait can be improved after physiotherapy based on the Bobath concept, but this should be further evaluated in larger controlled trials of patients with MS. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
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Cristina Benatti Silvia Alboni Giacomo Capone Daniela Corsini Federica Caggia Nicoletta Brunello Fabio Tascedda Joan M.C. Blom 《International journal of developmental neuroscience》2009,27(7):661-668
Protracted or recurrent pain and inflammation in the early neonatal period may cause long-lasting changes in central neural function. However, more research is necessary to better characterize the long-term behavioral sequelae of such exposure in the neonatal period. Objectives: (1) to study whether timing of postnatal exposure to persistent inflammation alters responsiveness to thermal pain in the adult animal; (2) to assess whether animals experiencing early postnatal chronic inflammation display altered anxiety related behavior; (3) to study the importance of genetic background. Newborn mice (outbred strain, CD1 and F1 hybrid strain, B6C3F1) received an injection of Complete Freund's Adjuvant (CFA) or saline on either postnatal day 1 or 14 (PND1; PND14) into the left hind paw. Pain to radiant heat and anxiety were examined in 12-week-old adult animals. Adult baseline PWL was significantly decreased in CD1 mice exposed to CFA on PND 1 and 14 as compared to their saline treated counterparts. B6C3F1 mice exposed to CFA on PND14 showed markedly reduced baseline PWL compared to the PND14 saline group. Persistent inflammation experienced by B6C3F1 mice on PND1 failed to affect baseline adult thermal responsiveness. Adult mice, CD1 and B6C3F1, displayed low anxiety traits only if they had been exposed to persistent inflammation on PND1 and not on PND14. Our research suggests a role for genetic background in modulating long-term behavioral consequences of neonatal persistent inflammation: the data support the hypothesis that pain experienced very early in life differentially affects adult behavioral and emotional responsiveness in outbred (CD1) and hybrid mice (B6C3F1). 相似文献
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Liv Wergeland Srbye Sigrunn Srbye Sveinung Wergeland Srbye 《Scandinavian journal of caring sciences》1995,9(2):119-122
In 1991/92, 289 students from four different schools of nursing in Norway participated in a case-related attitudes test. The nursing students answered questions concerning their personal views on the moral and legal implications of either assisting suicide or performing euthanasia. They also indicated whether they thermselves were willing to perform these acts. The results were compared with responses from a study on students from other faculties in 1988. The findings suggested that nursing students were significantly (p < 0.0005) more restrictive than the other students in their attitudes towards voluntary active euthanasia (VAE). Factors that influenced the nursing students' attitudes towards VAE were measured by the index of VAE. Religious belief (p < 0.0001), conservative political view (p < 0.01), and the perception of life as meaningful (p < 0.02) were the best predictors of the dependent variable. 相似文献
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