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31.
Summary The authors examined interleukin-2 (IL-2) production and interferon (IFN) production of peripheral blood mononuclear cells in 28 patients with renal cell carcinoma and 17 control subjects. The peripheral blood was obtained prior to the initiation of therapeutic procedures. The patients were divided into two groups according to tumor size, 5 cm and >5 cm. The production of IL-2 and IFN was measured by immunoradiometric assay. As a result, in the patients with tumors >5 cm, IL-2 and IFN production was impaired. However, in the patients with tumors 5 cm, IFN production was enhanced, though IL-2 production was not significantly different from that of the control subjects. There was no significant correlation between IL-2 production and IFN production.  相似文献   
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The action spectrum for resetting the phase of the circadian clock in Chlamydomonas reinhardtii is different depending upon whether the light stimuli are presented to cells that were in darkness versus dim illumination before stimulation. In this report, we show that phase resetting of illuminated cells appears to be mediated by components of the photosynthetic apparatus. This conclusion is based upon the action spectrum for phase-shifting illuminated cells (which looks like that for photosynthesis) and upon the fact that inhibitors of photosynthetic electron transport also inhibit the light-induced phase shift of illuminated cells. Both of these characteristics differ from that of cells taken from darkness. We, therefore, believe that at least two resetting pathways for this circadian clock exist and that both of these pathways are ecologically significant.  相似文献   
34.
To clarify trace element distribution in red and white muscle, and to verify two populations of muscle mitochondria, the iron, zinc, copper, and manganese concentrations of whole muscle and their subcellular fractions were determined. The iron, zinc, copper, and manganese concentrations of red muscle were 1.83, 4.31, 2.05, and 1.67 times higher than those of white muscle, respectively. In skeletal muscle subcellular distribution or iron, zinc, and copper were entirely different and that of manganese was relatively similar as compared with those in liver reported previously. The pattern of mineral distribution in all fractions of red muscle was similar to that of white muscle, but their concentrations in some fractions were different between red and white muscle, e.g., iron, zinc, and manganese in supernatant fraction and copper in nuclear and microsomal fractions. The difference between subsarcolemmal and interfibrillar mitochondria were ascertained by the distribution of trace elements.  相似文献   
35.
Summary Cellular and subcellular localizations of gastrin-releasing peptide-like immunoreactivity (GRP-LI) were examined in the perikarya of trigeminal ganglion cells. By immunolight microscopy using semi-thin sections, GRP-LI was observed in almost all the neuronal somata with various intensity as granular profiles distributing widely in the cytoplasm. By immunoelectron microscopy using ultrathin frozen sections and protein A-gold, GRP-LI was found predominantly in rounded or oval membrane-bound structures which were 300–800 nm in diameter and displayed various electron-density and heterogenous contents. Double-labeling immunoelectron microscopy using antibodies for GRP and cathepsin L, a well-characterized lyosomal proteinase, clearly demonstrated that these GRP-immunoreactive intracytoplasmic structures were lysosomes. In contrast, GRP-LI was detected only occasionally in the large granular vesicles (100–200 nm in diameter). These findings strongly suggest that considerable amount of GRP or GRP-like peptide is subject to intracellular degradation in the lysosome rather than to the regulatory secretion pathway, and this is the reason why no fibers immunoreactive for GRP have been detected in the peripheral sensory field.  相似文献   
36.
Summary A microcytofluorometrical DNA measurement was basically studied and was applied to single megakaryocytes previously identified on a Wright-Giemsa stained smear. The smear was first photographed and the location of each megakaryocyte was recorded on a cell map. The smear was then bleached with 50% acid ethanol and absolute methanol, and re-stained with 4,6-diamidino-2-phenylindole (DAPI) reagent (pH 7.4) at 4° C. Nuclear blue fluorescence was observed and the intensity of this fluorescence was proportional to the amount of DNA with the coefficient of variation (CV) of 3.6% when stained for 30 min. After 30 min DAPI staining, the DNA measurement was microcytofluorometrically performed in single megakaryocytes which had been morphologically classified into 4 groups on the basis of cytoplasmic maturation, Bessis' classification, assessed on Wright-Giemsa-stained bone-marrow smears from normal human beings. The histograms of the cells did not show any difference in DNA ploidy distribution among the classes: that is, the DNA histograms disclosed ploidy distribution from 4 N to 64 N with the largest population of 16 N. These findings suggest that nuclear DNA synthesis is completed before platelet production starts. This method is useful for comparing the morphological features and DNA content of single megakaryocytes.  相似文献   
37.
A theory of cell membrane transport with a time delay which predicts under certain conditions overshoot or oscillatory permeation (Ohshima and Kondo, Biophys. Chem. 33 (1989) 303), is extended with the introduction of a parameter expressing a fraction of solutes inside the cell interior that suffer time delay. It is found that criterion for oscillation depends strongly on this parameter. Results will also be presented for the case of an exponential-type distribution of the delay time.  相似文献   
38.
39.
The effects of pH, ionic strength, anion species, and antibody concentration on the adsorption equilibrium between immobilized antibodies and antigens were studied by use of anti-BSA, anti-HSA, anti-BlgG, and monoclonal anti-HSA coupled to Sepharose 4B. The polyclonal antibodies possessed average binding affinities of the order of 10(8)M(-1), and the heterogeneity was accounted for by assuming a normal distribution of the free energy of antibody-antigen combination. The monoclonal antibody, on the other hand, showed a homogeneous affinity of the Langmuir type. Bound antigens could be eluted by lowering pH or adding a chaotropic anion, and their purity was very high. The antibody ligand was sufficiently stable for repeated use.  相似文献   
40.
Nalidixic acid-resistant mutations of the gyrB gene of Escherichia coli   总被引:41,自引:0,他引:41  
Summary DNA fragments of 3.4 kb containing the gyrB gene were cloned from Escherichia coli KL-16 and from spontaneous nalidixic acid-resistant mutants. The mutations (nal-24 and nal-31) had been determined to be in the gyrB gene by transduction analysis. Nucleotide sequence analysis of the cloned DNA fragments revealed that nal-24 was a G to A transition at the first base of the 426th codon of the gyrB gene, resulting in an amino acid change from aspartic acid to asparagine, and nal-31 was an A to G transition at the first base of the 447th codon, resulting in an amino acid change from lysine to glutamic acid. This indicates that mutations in the gyrB gene are responsible for nalidixic acid resistance.  相似文献   
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