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41.
A blocking ELISA (B/ELISA) for detecting antibodies to bovine ephemeral fever virus (BEFV) in cattle is described. In this test, the binding capacity of a monoclonal antibody specific for an epitope on antigenic site G1 of the BEF virus glycoprotein is blocked in the presence of positive serum. The sensitivity of the B/ELISA was compared with the virus neutralisation (VN) test using a total of 380 sera from cattle. Of these, 118 were from an area known to be free of bovine ephemeral fever, 181 from naturally and experimentally BEFV-infected cattle, 33 sequential serum samples from a sentinel steer from which Berrimah virus (BERV) had been isolated, 9 from a sentinel cow from which Kimberley virus (KIMV) was isolated and a panel of 39 sera supplied as a blind trial. The B/ELISA results overall compared favourably with those of the VN tests. The monospecificity of the test was demonstrated using hyperimmune mouse ascitic fluid to other BEF serogroup viruses, namely KIM and BER viruses and the results showed no significant cross-reaction. The greater simplicity and sensitivity of the test when compared with the VN test makes it the preferred test for the diagnosis and monitoring of clinical bovine ephemeral fever.  相似文献   
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Treatment of severe haemophilia with factor concentrates is by self-infusion in the home. Adherence to record keeping on paper diaries is poor. A randomized-controlled trial compared adherence with record keeping of paper diaries with hand-held computers. Forty-one individuals with severe haemophilia, were randomized to hand-held computers (n = 22) or paper diaries (n = 19) and followed for 6 months. About 86.2% (679 of 788) of infusions by patients in the computer group were in compliance with the data submission schedule compared with only 48.3% (358 of 741) of infusions by patients using paper diaries (P < 0.0001). The time intervals between infusions and the receipt of data were shorter in the computer group (median 0.25 vs. 25 days respectively, P < 0.0001). Reminder phone calls by the clinic were made less frequently to users of hand-held computers than to users of paper diaries (median one vs. five times, P < 0.0001). Accuracy of data was similar for both methods. Compliance with hand-held computers was superior to paper diaries. The clinic received data from hand-held computers mostly on the same day, and nurses could thereby provide clinical advice more effectively. Although hand-held computers did not result in increased accuracy, errors could be detected and corrected more rapidly. Electronic data can more easily be verified, analysed and summarized than that from paper diaries.  相似文献   
43.
We report the evaluation of four new commercially available sensitive assay kits for determination of thyrotropin (TSH) and their clinical utility in normal subjects and patients with thyroidal and non-thyroidal illnesses. The sensitivity for the reliable detection of serum TSH by these methods ranged from 0.1-0.4 mU/L and their decreasing order was : NML greater than Serono greater than Abbott EIA greater than Hybritech. The coefficient of variation ranged from 2.0-5.8% for intra-assay and 2.3-8.6% for interassay at different concentration levels. Patients studied (n = 130) were assigned into four groups on the basis of the serum thyroxine value and their clinical findings. In total, there were 17 discrepancies (five with Hybritech, three with NML, five with Abbott EIA, and four with Serono) in making the correct diagnosis using these sensitive TSH methods as a single diagnostic test. These discrepancies were mainly in the same patients who were clinically euthyroid but had subnormal TSH values. There were no discrepancies in making the correct diagnosis for patients with hyperthyroidism or hypothyroidism using these sensitive TSH methods. Our observations indicate that the sensitive TSH methods are reliable in measuring subnormal levels and may be used to detect hyperthyroidism without affecting in any way their value in detecting hypothyroidism.  相似文献   
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The brains of pathogen-free autoimmune MRL/lpr, NZBWF1 and NZB mice were examined for central nervous system (CNS) inflammation in premoribund 8-week-old animals and at ages when active systemic lupus erythematosus (SLE) was present. CNS inflammation was observed only in MRL/lpr mice. Immunohistochemical studies of brains from young MRL/lpr mice found that infiltrates were composed primarily of CD4+ cells. Older MRL/lpr mice (22 and 26 weeks of age) had CD4+ cells predominantly, but CD8+ and B220+ cells were also present. Perivascular leakage of IgG was a prominent and unexpected finding in the MRL/lpr model. Congenic MRL/+ mice with late-onset autoimmunity had no inflammatory cells in brain tissue, and there was no perivascular staining with IgG or albumin. Our findings suggest that MRL/lpr mice are a useful model for studies of lupus-associated CNS inflammatory disease, and perivascular leakage may be a primary mechanism for entry of IgG into the brain.  相似文献   
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