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1.
For Apicomplexa (members) the host cell invasion is realized with the help of the organelles located at the apical tip of parasites. In this research paper the characterization of five chicken monoclonal antibodies (mabs) produced against Eimeria acervulina sporozoites is described. All mabs reacted with molecules belonging to the apical complex of chicken Eimeria sporozoites. On immunofluorescence assay (IFA) one mab, 8E-1, recognized an apical tip molecule present on all chicken Eimeria sporozoites, two mabs (8D-2 and HE-4) recognized an antigen present on the apical tip of the same two Eimeria species (E. acervulina and E. brunetti), another mab (5D-11) recognized an antigen present on the apical tip of other two species (E. acervulina and E. maxima) while one mab (8C-3) identified antigens present on the sporozoites and sporocysts wall of only E. acervulina. Besides the apical tip antigens, two mabs (HE-4 and 8D-2) recognized some proteins located in the anterior half of the sporozoites. Collectively, these mabs proved that the apical complex of chicken Eimeria sporozoites share one or more antigens that are expected to play a role in host cell recognition and invasion.  相似文献   
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Morphological characteristics of macropores in forest soil profiles were investigated at Hitachi Ohta Experimental Watershed in Japan. Nine individual profiles at different locations (various spatial scales in a catchment) and twenty profiles at one site (a small spatial scale) were excavated to the bedrock to investigate density, origin, diameter, direction, and gradient of macropores. Macropore densities in a soil profile ranged from 3.5 to 29.1 per m and from 5.4 to 75.1 per m2, respectively. Subsurface erosion, root channels, and interactions between subsurface erosion and root channels accounted for 36.9, 36.5, and 19.0%, of the described macropores. The mean macropore diameter in organic-rich soil layer (17–20 mm) was larger than in the B horizon (11–14 mm) at both spatial scales. The dominant gradients of all macropores in the organic-rich soil layer and B horizon were at negative oblique angles. Approximately 90% of the macropores in the organic-rich soil layer and approximately 80% of the macropores in the B horizon fell within the range between −50 and 50 degree planar direction. Subsurface flow and root systems are believed to play important roles in determining the morphological characteristics of macropores. These characteristics appear to have variable influences in different soil horizons rather than at different spatial scales. A part of this paper was presented at the 103th (1992) and 105th (1994) Annual Meetings of Japanese Forestry Society.  相似文献   
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ORF69 in the cyanophage infecting Microcystis aeruginosa, Ma-LMM01, shows homology to the family 19 chitinases where the catalytic domain has structural similarity to lysozyme. Chitinases hydrolyze chitin, a β-1, 4-linked monopolymer of N-acetylglucosamine (GlcNAc); whereas lysozymes hydrolyzes peptidoglycan, alternating β-1, 4-linked copolymers of N-acetylmuramic acid (MurNAc) and GlcNAc. Using amino acid sequence comparison to ORF69, the putative sugar binding residues, Gln162 and Lys165, from the barley chitinase (the model enzyme for the family 19 chitinases) corresponding to subsites −4 and −3 were found to be replaced with Gly209 and Ile213, respectively, in ORF69. To analyze their contribution to substrate binding affinity, ORF69 was cloned into Escherichia coli; and two mutant proteins G209Q and I213K were prepared using site-directed mutagenesis. The wild-type gene product (gp69) showed both lysozyme and chitinase activities. In contrast, the I213K mutant showed a decrease (70%) in lysozyme activity and a significant increase (50%) in chitinase activity; whereas, the G209Q mutant almost completely abolished both enzyme activities. The data suggest the Ile213 residue is involved in recognizing the substrate MurNAc; and Gly209 has significant contribution in chitinase and lysozyme activities for the wild-type gp69.  相似文献   
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A rapid bacterial identification method by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) using ribosomal proteins coded in S10 and spc operons as biomarkers, named the S10-GERMS (the S10-spc-alpha operon gene encoded ribosomal protein mass spectrum) method, was applied for the genus Bacillus a Gram-positive bacterium. The S10-GERMS method could successfully distinguish the difference between B. subtilis subsp. subtilis NBRC 13719(T) and B. subtilis subsp. spizizenii NBRC 101239(T) because of the mass difference of 2 ribosomal subunit proteins, despite the difference of only 2 bases in the 16S rRNA gene between them. The 8 selected reliable and reproducible ribosomal subunit proteins without disturbance of S/N level on MALDI-TOF MS analysis, S10, S14, S19, L18, L22, L24, L29, and L30, coded in S10 and spc operons were significantly useful biomarkers for rapid bacterial classification at species and strain levels by the S10-GERMS method of genus Bacillus strains without purification of ribosomal proteins.  相似文献   
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Although the release of growth hormone (GH) is known to be regulated mainly by GH-releasing hormone (GHRH) and somatostatin (SRIF) secreted from the hypothalamus, ghrelin also may be involved in GH release during juvenile period. We have examined plasma concentrations of acylated ghrelin, desacyl ghrelin, and GH in juvenile beagle dogs. Plasma acylated and desacyl ghrelin levels changed through aging; however, there was no closely correlation between ghrelin, body weight and circulating GH levels during juvenile period. The increase in body weight was essentially linear until 8 months of age, whereas plasma GH concentrations exhibited bimodal peaks for the meanwhile. The results suggest that ghrelin may not play internal cueing in GH secretion in juvenile beagle dogs.  相似文献   
9.
In order to determine insulin secretability and glucose utilization, a glucose tolerance test was performed in ateliotic cattle of 2 paternal strains; MHO and HSK cattle. MHO and HSK cattle showed different endocrine patterns in our previous study. Area under the insulin concentration curves (insulin-AUC) in the ateliotic cattle were significantly lower (122.3 +/- 59.4 ng.min/ml and 99.2 +/- 24.8 ng.min/ml for MHO and HSK cattle, respectively) than the control cattle (420.2 +/- 175.2 ng.min/ml). These low insulin responses to GTT may have an influence on growth retardation in MHO and HSK cattle.  相似文献   
10.
To analyze the structure of bacterial communities in spinach roots and in the nonrhizosphere soil, we used PeR-amplified 16S rRNA gene fragments separated by denaturing gradient gel electrophoresis (DGGE). DGGE revealed a large number of band patterns, which were ascribed to various bacterial species composing each of the bacterial communities. The pattern from the roots was less complex than that from the soil. It is considered that DGGE analysis is suitable for studies of bacterial community structure in soil-plant ecosystems.  相似文献   
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