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Monoclonal antibodies (MAbs) were raised against Penicillium aurantiogriseum var. melanoconidium. Cross‐reactivity studies were carried out against 12 ‘field’ and 27 ‘storage’ fungi. Two MAbs (MAbs 32 and 37) reacted with all of the fungi tested and a third (MAb 38) with 38 out of the 39 fungi (although weakly with some). Monoclonal antibodies 32 and 37, but not MAb 38, were found to react to a degree with ‘clean’ barley. Enzyme‐linked immunosorbent assay (ELISA) using MAb 38 and extracts of barley inoculated with the homologous antigen showed a clear relationship between absorbance and amount of fungal growth. It is suggested that these MAbs could be used in a broad‐spectrum assay to detect fungi of significance to the quality of foods and feeds.  相似文献   
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Primed and unprimed lymphocytes are usually classified as separate subsets of cells, based on phenotypic and functional distinctions. In the case of CD4+ T lymphocytes, primed cells are thought to proliferate more vigorously, quickly and easily, and to release a different profile of cytokines, than their naive equivalent. However, most of these data were obtained from studies in which populations of lymphocytes were compared before and after antigenic stimulation, and therefore did not distinguish between the effects resulting from the clonal expansion of specific precursor cells within such populations and those due to cell differentiation per se. We have investigated the contribution of precursor cell frequency to some of the functional changes observed in populations of CD4+ T cells following antigenic stimulation, using approaches in which antigen-specific precursor frequencies are high in both primary and secondary stimulations: mixed leukocyte reaction responses and cells from αβ T cell receptor transgenic mice. Our data suggest that when equivalent numbers of antigen-specific naive and previously primed CD4+ responder T cells are compared, there is no difference in their potency to proliferate but only the previously activated subset can generate cytokines such as interferon-γ.  相似文献   
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Studies were undertaken to assess the extent to which messenger RNA prepared from the postmortem Alzheimer's disease (AD) brain can be used for the successful preparation of a recombinant cDNA library. Initial experiments focused on the glial-specific marker glial fibrillary acidic protein (GFAP) since GFAP expression appeared to be a model for further studies on mRNAs that may continue to be expressed at high levels in the vicinity of lesioned sites in the AD brain. An AD cDNA library, prepared in the lambda gt11 expression vector system contained GFAP-specific recombinants. One of these was sequenced and the insert was shown to exhibit 88% homology with the similar sequence from mouse GFAP. As established by Northern blots, the size of the GFAP mRNA prepared from the routinely acquired postmortem AD cortex, approximately 2.7 kb, was the same as from a neurologically normal control brain. These results agree with earlier studies on GFAP mRNA from fresh mouse brain. The results demonstrate that in the postmortem AD brain, astroglial-specific mRNA remains sufficiently stable for molecular genetic analysis and may serve as a useful model for examining the genetic expression of mRNAs that may be related to the molecular pathogenesis and the etiology of AD.  相似文献   
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Conclusion From the above consideration we conclude that the stature of the boys and girls in all the age groups grew more rapidly than the other body segments under consideration. On the other hand, the arm girth grew very slowly. The mean values were progressively higher while the rate of growth and growth velocities were different in different age groups. The mean values of the lower extremity and biacromial indices were nearly constant in all the age groups which showed relatively equal growth of the stature in relation to lower extremity and shoulder breadth. From the Department of Anthropology, Lucknow University, Lucknow-226001.  相似文献   
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Three commercially available brands of amikacin were investigated in a parallel study design for the assessment of comparative pharmacokinetics in pediatric oncology patients with chemotherapy-induced neutropenic febrile episode. Amikacin concentration in serum samples was determined by fluorescence polarization immunoassay method using Abbott TDx system. Computer software, PK II was used for computation of pharmacokinetic parameters of amikacin. The serum concentration of all brands nonsignificantly (p > 0.05) varied at all time points, except at 1 and 2 hrs post dosing. At 1 hr post dosing, the serum concentration of brand II varied from rest of two brands. Whereas at 2 hr following I/V infusion, brands II and I were statistically different. Highest serum concentration of 38.69 +/- 1.45 microg/ml was observed in case of brand III while brands I and II showed lower but not significantly different serum concentration values, i.e., 36.30 +/- 1.65 and 37.89 +/- 1.32 microg/ml, respectively when compared with brand I. The other pharmacokinetic parameters of 3 brands found to have non-significant difference (P < 0.05) except, t(1/2)alpha and Cl of brands I and II that deviated statistically significant (p < 0.01). The relative bioavailability of brand II and III as compared with brand I, considered as standard 86.17 and 96.86%, respectively falls within the accepted limits of +/- 20% required for the bioequivalence of any two brands. Based upon findings of the present study, all these brands may be used interchangeably in oncology patients. Further studies, however are needed to determine whether the statistically elevated Cl value in brand II is of any clinical significance.  相似文献   
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