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The dot enzyme-linked immunosorbent assay (Dot-ELISA) and the enzyme-linked immunosorbent assay (ELISA) were compared with the immunofluorescent antibody test (IFA) for detection of IgM- and IgG-specific antibodies to human toxoplasmosis. Reciprocal titers were determined in all three assays using sera from 56 patients with suspected toxoplasmosis or with symptoms and diseases requiring exclusion of toxoplasmosis and control sera from 56 healthy persons. Using the Dot-ELISA, six patient sera (10.7%) were positive at titers of greater than equal to 1024 for IgM antibodies (titer range 1024-16 384) and 47 sera (84%) were positive for IgG antibodies (titer range 16-262 144) at a titer of greater than or equal to 16. One control serum was reactive for IgM (titer 1024) and 10 control sera (18%) were positive for IgG in the Dot-ELISA. In the ELISA, at titers of greater than or equal to 128, five sera (9%) were reactive for IgM (titer range 128-512) and 52 sera (92.8%) were reactive for IgG (titer range 32-8192) at a titer of greater than or equal to 32; no control sera gave positive reactions for IgM while 10 sera (18%) were positive for IgG in the ELISA. Using the IFA test at reciprocal titers of greater than or equal to 16, four sera (7.1%) were positive for IgM (titer range 32-512), and 51 sera (91%) were positive for IgG (titer range 16-8192). None was reactive for IgM, and eight sera (14%) were positive for IgG (titer range 32-128) in the IFA test. The Dot-ELISA correlated well with the IFA test (correlation coefficient = 0.895) and the ELISA correlated slightly higher with the IFA test (correlation coefficient = 0.910) for detection of IgG antibodies to Toxoplasma gondii.  相似文献   
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The molecular profile and the biological response of isolates of Pyricularia oryzae Cavara obtained from ctenanthe to two strobilurins (azoxystrobin, kresoxim-methyl) and the phenylpyridinamine fungicide fluazinam were characterized, and compared with isolates from rice plants. Five different isozymes (alpha-esterase, lactate, malate, isocitrate and sorbitol dehydrogenases) and five random decamer primers for RAPD-PCR were used to generate molecular markers. Using unweighted pair-group with arithmetic average analysis, ctenanthe isolates were found to form a separate group distinct from that of the rice isolates for both sets of markers. Amplified polymorphic sequences of mitochondrial cytochrome b that were digested with Fnu4HI or StyI revealed no differences among Pyricularia isolates at amino acid positions 143 or 129 which confer resistance to strobilurins in several fungi. In absence of the alternative respiration inhibitor salicylhydroxamic acid (SHAM) the three fungicides showed inferior and variable efficacy, with a trend toward the rice isolate being less sensitive. The addition of SHAM enhanced the effectiveness of all fungicides against isolates regardless of their origin. Appressorium formation was the most vulnerable target of action of the respiration inhibitors and azoxystrobin the most effective. This is the first report of a comparison between the molecular profiles and sensitivities to respiration inhibitors for Pyricularia oryzae isolates from a non-gramineous host and from rice.  相似文献   
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One of the many challenges of building a scalable quantum computer is single-shot measurement of all the quantum bits (qubits). We have used simultaneous single-shot measurement of coupled Josephson phase qubits to directly probe interaction of the qubits in the time domain. The concept of measurement crosstalk is introduced, and we show that its effects are minimized by careful adjustment of the timing of the measurements. We observe the antiphase oscillation of the two-qubit 01 and 10 states, consistent with quantum mechanical entanglement of these states, thereby opening the possibility for full characterization of multiqubit gates and elementary quantum algorithms.  相似文献   
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A new method for mass percentage determination of fructose and glucose based on FT-Raman spectroscopy is evaluated with a standard HPLC-based method. FT-Raman spectra manipulation is done via the spectrometer software, and a PLS (partial least squares) method is developed with the TQ Analyst software (Ver 1. 1a). The simultaneous quantitative determination uses an input range from 1700 to 700 cm(-1) without correction or baseline factors. The standards used in the PLS method are honey samples previously analyzed by HPLC to obtain their mass percentage concentrations in fructose and glucose. The returned results are statistically tested with those of the HPLC method. Both methods appear to score equally in terms of reproducibility. The honey content of the two sugars in total was found up to 40-74%. The honey samples content in fructose and glucose was determined by HPLC (24.1-42.9% and 16.2-33.1%, respectively) and FT-Raman (24.0-40.8% and 21.1-32.2%, respectively).  相似文献   
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The dot enzyme-linked immunosorbent assay (Dot-ELISA), standard ELISA and the complement fixation (CF) tests were compared in the serodiagnosis of African visceral leishmaniasis (kala-azar). Assay sensitivity was determined using sera from 44 patients with parasitologically confirmed kala-azar. Using the Dot-ELISA, 42 of 44 patients (95%) were positive at a reciprocal titer of greater than or equal to 32 (titer range 512-524 288). In the standard ELISA technique, 43 of 44 patients (98%) were positive (titer range 32-32 768). At a reciprocal titer of greater than or equal to 8 in the CF test, 35 patients (80%) were positive, 1 (2%) was negative and 8 patients (18%) showed anticomplementary (AC) activity (titer range 8-2048). Specificity, determined using 33 sera from healthy individuals not living in endemic areas, was 97% in both the Dot-ELISA and the standard ELISA (32 of 33 sera); in he CF test, all sera were negative except 1 (3%) which showed AC activity. Sera from patients with Chagas' disease cross-reacted in the dot-ELISA up to a titer of 512. In the standard ELISA, cross-reactions occurred mainly using sera from patients with Chagas' disease, malaria and syphilis, and to a lesser extent with sera from amebiasis, schistosomiasis and trichinosis patients. Overall titer agreement in replicate experiments was highest in the Dot-ELISA (89%), followed by the standard ELISA (80%) and the CF test (72%).  相似文献   
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I would say that the ultimate position holders of the D.V.A. find themselves in, is very largely dependent on the course of events over the next few years and in no small measure to their own endeavours. I feel that the holders of the D.V.A. should view this training period as one in which they have enlarged their own over all appreciation of the subject they have studied and have therefore, gained for themselves a material advantage over other members of the profession who have not in fact followed this line of study and that although there is a certain amount of despondency in the ranks of the veterinary anaesthetists at the moment, this should not be allowed to become an obstacle in the progressive development of this group.  相似文献   
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