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Background  

We have previously shown that supernatant from Candida albicans (CA) culture contains a Secretory Interleukin (IL)-12 Inhibitory Factor (CA-SIIF), which inhibits IL-12 production by human monocytes. However, the effect of CA-SIIF on secretion of other cytokines by monocytes is unknown, and detailed characterization of this factor has not been performed.  相似文献   
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The formation of R-prime plasmids was selected in crosses involving soybean microsymbionts with genomic Tn5 insertions and carrying plasmid pJB3JI (with one IS2) copy as donors and Escherichia coli HB101 as recipient. Whereas the parent plasmid was 60 kb, recombinant plasmids between 76 kb and 121 kb were obtained. Restriction and Southern analyses confirmed the mobilization of Tn5 on four R-primes from Bradyrhizobium japonicum I-110 and on an R-prime plasmid from Rhizobium fredii HH303. The largest R-prime plasmid was obtained from the rescue of two symbiotically defective R. fredii mutant strains that required adenosine.Non-standard abbreviation TDP transposon donor pool Scientific article number A-4728 and contribution number 7724 of the Maryland Agricultural Experiment Station  相似文献   
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Alkaline sucrose solution was demonstrated to be a good solvent for the solubilization of water-insoluble drugs. At high concentration and alkaline pH, sucrose solubilizes water-insoluble molecules through intramolecular conformations. Tetracyline and chloramphenicol, when dissolved in alkaline sucrose solution, retained their bactericidal activity. Gel permeation-chromatography analysis and atomic-force-microscopy studies confirmed the formation of sucrose-antibiotics complex.  相似文献   
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Receptors for estradiol, progesterone and dihydrotestosterone have been demonstrated in normal growing breasts of young females below 25 years.  相似文献   
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The liver plays a key role in removing harmful chemicals from the body and is therefore often the first tissue to suffer potentially adverse consequences. To protect public health it is necessary to quantitatively estimate the risk of long-term low dose exposure to environmental pollutants. Animal testing is the primary tool for extrapolating human risk but it is fraught with uncertainty, necessitating novel alternative approaches. Our goal is to integrate in vitro liver experiments with agent-based cellular models to simulate a spatially extended hepatic lobule. Here we describe a graphical model of the sinusoidal network that efficiently simulates portal to centrilobular mass transfer in the hepatic lobule. We analyzed the effects of vascular topology and metabolism on the cell-level distribution following oral exposure to chemicals. The spatial distribution of metabolically inactive chemicals was similar across different vascular networks and a baseline well-mixed compartment. When chemicals were rapidly metabolized, concentration heterogeneity of the parent compound increased across the vascular network. As a result, our spatially extended lobule generated greater variability in dose-dependent cellular responses, in this case apoptosis, than were observed in the classical well-mixed liver or in a parallel tubes model. The mass-balanced graphical approach to modeling the hepatic lobule is computationally efficient for simulating long-term exposure, modular for incorporating complex cellular interactions, and flexible for dealing with evolving tissues.  相似文献   
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Antikinetochore immunofluorescence staining has been used in several studies to determine whether a second kinetochore is present, active, or both, in multicentric chromosomes. All of these studies have used tissue culture cells, and contended with the problem of obtaining well spread, banded metaphase chromosomes without affecting the kinetochore staining. We have adapted hypotonic, centrifugation and chromosome staining techniques to obtain simultaneous Q-banding and bright kinetochore staining of chromosomes from human lymphocytes.  相似文献   
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A comparison of different methods for the detection of cervical human papillomavirus (HPV) infection was made on patients attending the cervical dysplasia clinic. Cytomorphology, immunocytochemistry and in situ hybridization were compared for their ability to detect HPV. Separate cervicovaginal smears from 50 patients were tested for HPV types 6/11, 16 and 18 by in situ hybridization using 35S-labeled DNA probes. Duplicate smears from the same patients were Papanicolaou stained and evaluated for evidence of condylomatous and dysplastic changes. Twenty-five matching cervical biopsies were immunostained for HPV capsid antigen and tested by in situ hybridization for HPV DNA. The cytologic smears of 20 patients (40%) were positive for HPV DNA. Six patients had HPV 6/11, ten had HPV 16, three had HPV 18, and one had both HPV 6/11 and HPV 16. There was a high correlation between condylomatous cytopathology and antigen and DNA detection. One-third of the specimens with condylomatous changes were DNA negative by the tested probes, suggesting the presence of other HPV types in the genital tract.  相似文献   
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