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931.
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934.
ANCA directed against PR3 are highly specific for Wegener's granulomatosis and microscopic polyangiitis, and have been implicated in the pathogenesis of small vessel vasculitis. Most PR3-ANCA are directed against conformational epitopes on PR3. This study was designed to determine whether the cleavage of the N-terminal activation dipeptide of PR3 is required for the binding of PR3-ANCA. Recombinant PR3 (rPR3) variants were expressed in the epithelial cell line, 293. As confirmed by radiosequencing, the rPR3 secreted into the 293 cell culture supernatant is N-terminally unprocessed. Two enzymatically inactive rPR3 mutants were expressed in 293 cells: rPR3-S176A and delta-rPR3-S176A. rPR3-S176A contains the N-propetide Ala-2-Glu-1, delta-rPR3-S176A does not. Culture supernatants of rPR3-S176A and delta-rPR3-S176A expressing 293 cells were used as sources of target antigen for PR3-ANCA testing by capture ELISA. Forty unselected consecutive PR3-ANCA+ sera were tested. With delta-rPR3-S176A as antigen all 40 were recognized, compared with only 34 of 40 when rPR3-S176A served as target antigen. The majority of the serum samples contained a mixture of antibodies reacting with epitopes accessible on the mature and on the proform of PR3. In conclusion, the cleavage of the N-terminal activation dipeptide of PR3 is not an absolute requirement for recognition by all PR3-ANCA. However, a substantial proportion of PR3-ANCA recognize (a) target antigen(s) exposed only after the conformational change of PR3 associated with the N-terminal processing. In 15% of sera this PR3-ANCA subset occurred exclusively. PR3-ANCA subtypes can be differentiated using specifically designed rPR3 variants as target antigens, and non-haematopoietic mammalian cells without regulated secretory pathway can be used for their expression.  相似文献   
935.
936.
An ecoregional approach to the classification of malaria in the neotropics region can give health personnel a new prespective on how to manage malaria control programs. We propose an ecoregional classification based on vector distribution and important environmental determinants, including vegetation type, rainfall patterns, mean temperatures, elevation, and geomorphology. The following 5 ecoregions are described: (1) coastal, (2) piedmont, (3) savanna, (4) interior lowland forest, and (5) high valley. Subregional differences are classified when appropriate. Because human activities and extensive changes in land use usually leads to increased human-vector contact and alter local vector distribution and abundance, it is important that these changes be considered in the classification of vector ecoregions. Using this approach, risk areas can be classified as to the presence and potential abundance of particular vectors. Then, in combination with other components of malaria transmission (e.g., migration, cultural practices, living conditions), areas for surveillance and intervention can be prioritized. It is hoped that this forum will be a catalyst for discussion, future research, and the development of ecologically orientated malaria control programs.  相似文献   
937.
Telephone-Linked Care (TLC) technology has been developed and applied as an alternative to and a supplement for office visits as a means to deliver ambulatory care. TLC is used to monitor patients with chronic diseases, counsel patients on important health behaviors, and provide information and support to home caregivers of patients with disabling conditions. TLC speaks to patients over the telephone in their homes using computer-controlled digitized human speech. Patients use their telephone keypad to communicate. TLC conversations last 2-15 minutes per call and take place weekly for periods of at least 3 months. The conversations consist of a salutation, password verification, the core clinical part, and a closing. The structure of the clinical part is similar for each of the application groups: chronic disease, health behavior, and caregiver support. The system architecture consists of linked voice and database components and their subcomponents. Preliminary evaluation indicates that TLC is well accepted by patients and their providers and can improve clinical outcomes.  相似文献   
938.
Newborn Holstein heifers (n = 32) and bulls (n = 12) were used to investigate the use of dry feed intake as a percentage of birth weight as a weaning criterion. Three different percentages (1, 1.5, and 2%) were used. Calves in the 1% treatment group met the weaning criterion earlier than did those in the 1.5 and 2% treatment groups; no difference was detected between the latter two groups. Total dry feed intake at 8 wk was higher for calves in the 1% treatment group than for calves in the other treatment groups; no difference was detected between the 1.5 and 2% treatment groups. Weights for all calves at 8 wk and weights of heifer calves at 12, 16, and 20 wk were not different among groups. Using dry feed intake at 1% of birth weight as a weaning criterion reduced days to weaning, increased dry feed intake from birth to 8 wk, decreased variation in weaning age, and had no apparent negative effect on growth at 20 wk of age. Using dry feed intake as a percentage of birth weight appears to be a suitable criterion to determine when to wean dairy calves.  相似文献   
939.
Pigeons were trained to peck 2 different buttons in response to 16-icon Same versus Different arrays. In Same arrays, the icons were identical to one another, whereas in Different arrays, the icons were different from one another. In Experiment 1, pigeons discriminated Same from Different arrays and transferred their discriminative responding to arrays of novel icons. In Experiments 2–4, pigeons exhibited sensitivity to the degree of display variability when shown intermediate Mixture arrays. Entropy, an information theoretic measure, systematically described these results while outperforming rival accounts. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
940.
In patients with systemic lupus erythematosus (SLE) and concomitant Coombs positive autoimmune haemolytic anaemia (AIHA) anticardiolipin antibodies (aCL) are found more frequently and at higher titres than in SLE patients without AIHA. In order to assess if aCL elevation is primarily associated with the underlying SLE, or with AIHA itself, we examined AIHA patients with and without underlying SLE for the presence of aCL. aCL (IgG and IgM) were determined by ELISA in 74 SLE patients without AIHA, 22 SLE patients with AIHA, 50 patients with idiopathic AIHA (warm-reactive autoantibodies), 52 patients with idiopathic AIHA (cold-reactive autoantibodies) and 50 healthy controls. The mean IgG and IgM aCL titres in SLE patients without AIHA (IgG 37.0 U/ml, IgM 8.9 U/ml) were significantly elevated compared with the values in healthy controls (IgG 9.1 U/ml, IgM 3.2 U/ml; P < 0.005). The mean aCL levels in SLE patients with AIHA (IgG 53.2 U/ml, IgM 28.2 U/ml) were higher than in SLE patients without AIHA (P = 0.09 for IgG, P < 0.005 for IgM). Interestingly, the mean aCL levels of patients with idiopathic AIHA (warm-reactive autoantibody type: IgG 29.2 U/ml, IgM 19.3 U/ml; cold-reactive autoantibody type: IgG 27.4 U/ml, IgM 18.9 U/ml) were also significantly elevated compared with healthy controls P < 0.001). As aCL are elevated not only in SLE (with and without concomitant AIHA) but also in idiopathic AIHA it can be speculated that aCL are involved in the pathomechanism of autoantibody-induced erythrocyte destruction per se irrespective of an underlying SLE.  相似文献   
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