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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.
Objective: The scientific quality of research is an important ethical issue. To clarify the quality of research projects in pharmacotherapy/pharmacology,
40 randomly selected research projects in pharmacotherapy/pharmacology submitted to a research ethics committee were reviewed.
Results: Eight of the projects would not have contributed new knowledge nor were they necessary as controls for the results of previous
research. Fifteen of the research protocols were of good quality, 15 could be used after revisions, and 10 were unfit for
use. Eleven of the research projects were not finished 5 years after they were started. A written report was produced from
26 of the projects. Nine were of good quality and could be accepted for publication in a medical journal, 10 of the reports
were in need of revision before publication, and 7 should not be accepted for publication.
Conclusion: Research in this field ought to be improved, and ways to improve the standard of clinical trials in pharmacotherapy are
dicussed.
Received: 1 April 1996 / Accepted in revised form: 28 June 1996 相似文献
3.
Atle Dyregrov 《Journal of traumatic stress》1997,10(4):589-605
Critical Incident Stress Debriefings have become an intervention method used in various cultures, countries and groups following critical incidents. Although the structure of such meetings has been adequately described, utilization of the group processes involved has received less attention. A model, process debriefing (PD), based on experiences from Europe, is presented. Some differences between the current CISD process in the United States and the Europe based model are outlined. Various factors that impact the process of debriefings are discussed with a special emphasis on leadership, and implications of these group process variables for psychological debriefing are presented. It is emphasized that the continued exploration and discussion of process issues is critical to advance the understanding of the critical elements of debriefing. 相似文献
4.
Interactions between 5-hydroxytryptamine (5-HT) and substance P (SP) in the mouse spinal cord were investigated using the tail-flick test and the behavioral response evoked by intrathecal (i.th.) SP or i.th. 5-HT. I.th. injection of 5-HT (20 μg) or the 5-HT1 receptor agonists(+)-8-hydroxy-2-(di-n-propylamino)tetralin ((+)-8-OH-DPAT) (20 μg) or 5-methoxy-3(1,2,3,6-tetrahydropyridine-4-yl)-1H-indole (RU 24969) (20 μg) markedly inhibited the tail-flick reflex. The effect of these compounds was reduced when SP (5 μg) was given i.th. 55 min, or 55 and 45 min before the agonists. The tail-flick latencies recorded 5 min before injection of a 5-HT agonist were similar in animals treated with SP or vehicle. The changes in the tail-flick test were not due to changes in tail skin temperature since only minimal differences in the skin temperature were recorded between the groups injected with SP or vehicle. I.th. injection of SP (10 ng) or 5-HT (2 μg) produced a similar behavioral response consisting of biting, licking and scratching of the caudal part of the body, indicative of nociceptive stimulation. The responses both to i.th. SP and 5-HT were reduced after i.th. application of SP receptor antagonist [d-Arg1,d-Trp7,9,Leu11]-SP (Spantide) (5 μg), as well as 5 min after i.th. injection of the 5-HT receptor antagonist metergoline (4 μg). The data may indicate functional interactions between SP and 5-HT in the mouse spinal cord, which may take place in neurons involved in the processing of nociception. 相似文献
5.
D B Kingsmore D J Hole C R Gillis W D George 《European journal of surgical oncology》2005,31(3):226-231
AIM: To determine whether axillary recurrence reflects inadequate axillary treatment or adverse pathological features. METHODS: The case-records were reviewed of 2122 women aged under 75 years, treated for invasive breast cancer during the time-period 1/1/86-31/12/91 in a geographically defined area. Data were abstracted on operations performed, pathological features, post-operative treatments and details of axillary recurrence. The risk of axillary recurrence was examined by pathological, treatment and patient factors. RESULTS: Axillary recurrence was more than twice as likely after inadequate compared to adequate treatment of the axilla (adequate staging or axillary radiotherapy or clearance). Delayed treatment of the axilla was not as successful as adequate primary treatment: multiple axillary recurrences were twice as common, one third of which were uncontrolled at time of death. Inadequate surgical treatment was associated with increased rates of recurrence despite endocrine therapy, chemotherapy or radiotherapy. Lymphoedema was twice as common if axillary radiotherapy was combined with any axillary surgical procedure. CONCLUSIONS: Axillary recurrence is more common in tumours with adverse pathology but may also result from inadequate axillary treatment. In order to minimise axillary recurrence, optimal treatment of the axilla entails adequate staging (sampling of four or more nodes) and treatment (axillary clearance or radiotherapy and endocrine therapy) in all women. 相似文献
6.
The effect of (+/-), (+) and (-)-nefopam on the uptake of 5-hydroxytryptamine (5-HT), noradrenaline and dopamine in synaptosomal preparations from rat forebrain, hippocampus and striatum has been investigated. All three forms of nefopam inhibited the amine uptake in the investigated structures, the order of potency being (+) greater than (+/-) greater than (-). (+)-Nefopam was 7-30 times more potent than (-)-nefopam. The same order of potency has also been found for the antinociceptive effect of these three forms, however, the differences were smaller. Inhibition of 5-HT and noradrenaline uptake may not be the sole mechanism underlying the analgesic effect of nefopam. 相似文献
7.
Elective versus emergency surgery for patients with colorectal cancer. 总被引:11,自引:0,他引:11
A prospective study of 570 patients presenting with colorectal cancer over a 6-year period was undertaken. Of these, 363 were admitted electively and 207 presented as emergencies. The outcome following elective admission was more favourable than after emergency admission. In the elective group the proportion of resected tumours was greater (77 versus 64 per cent, P less than 0.001), the operative mortality rate lower (9 versus 19 per cent, P less than 0.001) and the 5-year disease-related survival rate higher (37 versus 19 per cent, P less than 0.001). These differences may relate to the greater resection rates in the elective situation. Results of surgical intervention might be improved if emergency colorectal operations were undertaken by surgeons with more experience of this type of surgery. 相似文献
8.
P. K. Eide K. Hole O. -G. Berge 《Journal of neural transmission (Vienna, Austria : 1996)》1988,73(1):31-41
Summary The putative serotonin (5-HT) receptor antagonist metitepin (0.5 mg/ kg, intraperitoneally) produced hypoalgesia in the increasing temperature hot-plate test and hyperalgesia in the tail-flick test in mice. The effects of metitepin were not altered after depletion of 5-HT by the neurotoxin 5,7-dihydroxytryptamine (5, 7-DHT, 80 g free base, intracerebroventricularly) or the serotonin synthesis inhibitor p-chlorophenylalanine (PCPA, 400 mg/kg for 10 consecutive days). After chronic administration (2 or 5 mg/kg for 18 consecutive days) tolerance to the effect of metitepin (0.5 mg/kg) and cross-tolerance to the antinociceptive effect of the 5-HT agonist 5-methoxy-N,N-dimethyltryptamine (5-MeODMT, 3 mg/kg) was found in the hot-plate test but not in the tail-flick test. It is suggested that metitepin may block descending 5-HT transmission while more complex mechanisms of action are involved at supraspinal level. One possibility is that metitepin exhibits partial agonist properties or, alternatively, that the drug may block 5-HT subsystems which tonically enhance nociception. 相似文献
9.
The rabbit has two isotypic forms of the immunoglobulin kappa light chain, K1 and K2, which probably arose by duplication. In the normal rabbit, only traces of K2 light chains are produced. However, K2 levels are elevated in allotype-suppressed rabbits and in the Basilea strain which does not produce K1 because of a K1 mRNA splice site mutation. Previous cloning and sequencing showed that each isotype has its own set of J kappa genes but it was not known whether the two isotypes utilize shared or separate sets of V kappa genes. In addition, although genetic linkage of allotypes associated with the K1 and K2 genes has been demonstrated, physical linkage had not been previously demonstrated by overlapping cosmid or phage clones. We used pulsed field and transverse alternating field electrophoresis to obtain megabase maps and to estimate the size of the duplication of the rabbit kappa light chain locus. We found that the two C kappa genes are about 1 megabase apart. One explanation for the poor expression of K2, could be great physical distance from V kappa genes. However, we found that there are V kappa, J kappa and C kappa 2 genes within a approximately 105-kb fragment. Thus, physical distance of V kappa from C kappa 2 may not be the basis for poor K2 expression. 相似文献
10.
Radiation dose measurements with alanine/agarose gel and thin alanine films around a 192Ir brachytherapy source,using ESR spectroscopy 总被引:6,自引:0,他引:6
Olsson S Bergstrand ES Carlsson AK Hole EO Lund E 《Physics in medicine and biology》2002,47(8):1333-1356
Alanine/agarose gel and alanine films in stacks have been used for measurements of absorbed dose around an HDR 192Ir source in a vaginal cylinder-applicator, with and without a 180 degrees tungsten shield. The gel and the films were analysed by means of ESR spectroscopy and calibrated against an ion chamber in a 4 MV photon beam to obtain absolute dose values. The gel serves as both dosimeter and phantom material, and the thin (130 microm) films are used to achieve an improved spatial resolution in the dose estimations. Experimental values were compared with Monte Carlo simulations using two different codes. Results from the measurements generally agree with the simulations to within 5%, for both the alanine/agarose gel and the alanine films. 相似文献