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51.
52.
Detection of Marek's disease virus antigens and DNA in feathers from infected chickens 总被引:1,自引:0,他引:1
Two novel tests, enzyme-linked immunosorbent assay (ELISA) and dot-blot hybridization, were developed to detect and quantify the antigens and DNA of Marek's disease virus (MDV) in feather tips from infected chickens. In both methods, buffered extracts of the feathers served as the same test material. The ELISA technique was compared to the conventional agar-gel precipitation (AGP) test, using the same convalescent serum from a MDV-infected bird. Of 86 feather samples tested, 34 were negative by both methods, while 6 out of 52 were ELISA positive but AGP negative. Viral antigen detection by the AGP and ELISA methods was compared with the detection of MDV DNA by the dot-blot DNA hybridization technique. At an ELISA reading (OD 405) of 0.3 and above, only 5 out of 48 DNA extracts failed to hybridize with the MDV-DNA probe. The use of the radioactively labelled MDV-DNA probe for hybridization with DNA extracts from feather tips of MDV-infected chickens was both sensitive and specific, and there was good correlation among the different tests. 相似文献
53.
The authors developed a statistically based method for determining whether inpatient or outpatient placement is most appropriate for a given patient. This study assesses the method's accuracy by comparing statistical classifications of a random sample of inpatients at five New York State facilities with the classifications of multidisciplinary clinical teams. The statistical method proved to be very strong in screening patients who should not be considered for community placement and in four of the five facilities was also strong in identifying appropriate outpatients. The authors discuss the method's implications for outpatient screening and outpatient programs. 相似文献
54.
Although the partial benzodiazepine receptor inverse agonist, Ro 15-4513, counteracts many ethanol effects, its effect on operant behavior or on ethanol-induced changes in this behavior, remains controversial. In this study, we examined the effects of Ro 15-4513, ethanol, and their interaction on behavior maintained by an FR 20 schedule of food reinforcement. Ro 15-4513 (1.0-4.0 mg/kg) and ethanol (1.5-3.0 g/kg) reduced lever-responding of both male and female mice. The disruptive effect of Ro 15-4513 was of short duration (approximately 10 min), and was greater in male than in female mice. Under equivalent dose and time parameters, ethanol disrupted behavior of both sexes to the same extent. In spite of the disruptive effects of both drugs when given alone, when given after ethanol and prior to testing, Ro 15-4513 attenuated the disruptive effects of ethanol in male mice. The present study extends previous reports by documenting: (1) that the disruptive effect of Ro 15-4513 on mice is of very short duration and occurs at lower doses than previously reported; (2) that, in spite of being disruptive itself, Ro 15-4513 can attenuate the disruptive effects of ethanol on schedule controlled behavior; and (3) that gender is an important consideration in determining the effects of this compound. 相似文献
55.
Neuropathological findings in two siblings with familial erythrophagocytic lymphohistiocytosis (FEL) are reported. Case 1 showed the typical neuropathological findings of FEL with lymphohistiocytic infiltration of the leptomeninges and perivascular spaces. A characteristic erythrophagocytosis was detected in inguinal lymph nodes, lung and bone marrow. Case 2 revealed calcification and necrotic lesions in the brain. In the necrotic areas, parenchymal calcification, vascular medial calcification, and occlusion of many vessels due to subendothelial fibrosis were detected. The areas of necrosis correlated with the distribution of occluded vessels. These changes were most prominent in putamen, internal capsule, thalamus and dentate nucleus. Hypercytokinemia is suspected to be the underlying mechanism for the clinical and laboratory findings in patients with FEL, although the relationship to the vascular pathology is unclear. 相似文献
56.
Andreas Machner Harry Merk Roland Becker Kerstin Rohkohl Heiko Wissel G za Pap 《Acta orthopaedica》2003,74(1):85-88
A proprioceptive deficit is an important determinant of disability in various shoulder disorders, such as instability and osteoarthrosis. In 15 patients with impingement syndrome stage II (Neer 1983), who were treated by arthroscopic subacromial decompression, we measured movement sense by determining threshold levels for the perception of motion of the shoulder. The patients were placed in a specially designed chair allowing continuous passive motion of the shoulder joint, while avoiding cutaneous, auditory and visual stimuli. To assess movement detection thresholds, passive abduction movements of the shoulder were performed at a starting angle of 60°, an amplitude of 10° and an angular velocity of 1.3°/s. Before surgery, all patients had higher threshold levels for the perception of motion in their affected shoulders then in the other side. After decompression, proprioception had improved on the decompressed side, but was unchanged on the other side. 相似文献
57.
Utilizing a lateral fluid percussion injury as a model of cerebral concussion, rats were studied histochemically measuring the degree of cytochrome oxidase activity present within different structures at different times following injury. After concussion, the cerebral cortex ipsilateral to the site of injury exhibited a diffuse decrease in its level of chromotome oxidase (CO) activity beginning at as soon as one day and lasting for up to 10 days after the insult. The ipsilateral dorsal hippocampus also exhibited an injury-induced decrease in CO activity, however, it was not as severe as in the cortex. These results indicate that oxidative metabolism is depressed primarily within the cerebral cortex and hippocampus for several days following a cerebral concussion. We propose that this period of metabolic depression may delineate a period of time during which the injured brain is unable to function normally and thus would be vulnerable to a second insult. 相似文献
58.
59.
60.
P. Satz K. Zaucha D. L. Forney C. McCleary R. F. Asarnow R. Light H. Levin D. Kelly M. Bergsneider D. Hovda N. Martin M. J. Caron N. Namerow D. Becker 《Brain injury : [BI]》1998,12(7):555-567
Traumatic brain injury (TBI) subjects at Glasgow Outcome Scale levels 3 (severe disability), 4 (moderate disability), 5 (good recovery), and an other injury control group (OIC) were compared in terms of neuropsychological, psychosocial, and vocational functioning 6 months after injury. Subjects were a sample of 100 patients with a moderate to severe traumatic brain injury (TBI) and a matched sample of 30 other injury control subjects (OIC) enrolled in the UCLA Brain Injury Research Center study of TBI outcome. Overall, the results showed a systematic decrease in mean neuropsychological test performance as a function of increasing GOS severity, as well as an increased prevalence of symptoms of depression and lower ratings on measures assessing employability and capacity for self care. TBI patients in the 'severe' and 'moderate disability' groups were distinctly inferior to the 'good recovery' and 'OIC' groups, who were quite similar to each other in terms of cognitive, psychosocial, and vocational outcomes. The results demonstrate overall support for the predictive and concurrent validity of the GOS 6 months post injury. Despite these results, which strengthen the utility and appeal of the GOS for multicentre studies, concerns still remain regarding GOS category 4 (moderate disability), which was shown to lack sufficient discriminability in this study. 相似文献