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11.
Abstract Granulocyte colony-stimulating factor (G-CSF) stimulates a subset of granulocyte colony forming cells and when administered to neutropenic individuals results in recovery of blood neutrophil numbers to normal levels. Therefore, G-CSF may be a useful therapeutic agent for infections in immunocompromised hosts. However, to date there has been only limited information that G-CSF activates the antimicrobial activity of neutrophils. In the present study, we found that recombinant G-CSF promotes the anti- Candida albicans activity of normal human blood polymorphonuclear (PMN) cells in vitro using both a 3H-glucose uptake procedure and a Candida colony counting assay. As little as 0.1 ng/ml G-CSF induced significant anti-Candida activity in the PMN cultures. G-CSF treatment also enhanced superoxide anion production by the PMNs in response to f-MLP as determined by the superoxide dismutase inhibitable cytochrome C reduction method. Such results show that G-CSF can promote the antimicrobial activity of peripheral blood PMNs against C. albicans .  相似文献   
12.
Two new shrimp-associated gobies,Amblyeleotris yanoi sp. nov. andA. masuii sp. nov. are described on the basis of specimens from Iriomote-jima Island and Okinawa-jima Islands, Okinawa Prefecture, Japan.A. yanoi is distinguished from other members of the genus by the combination of the following characters: 14 anal fin soft rays, 19 pectoral fin rays, 97–103 longitudinal scales, a candle flame-shaped marking on the caudal fin, a very low membrane connecting the pelvic fins and absence of a ventral frenum.A. masuii differs from all other congeners by having 92–97 longitudinal scales, the length of the interpelvic connecting membrane relative to the longest pelvic fin ray (0.43–0.66), black blotches on the sides of the chin, and blue spots on the opercle and preopercle.  相似文献   
13.
Using a plasmid pBsr2 which carries a blasticidin S-resistant gene, we have improved the method of REMI (restriction enzyme-mediated integration) provided for insertional mutagenesis inDictyostelium discoideum (bsr-REMI). To confirm usefulness of thebsr-REMI, transformation efficiency, copy number of integrated DNA, and randomness of integration into genome were examined.  相似文献   
14.
Total phospholipids were extracted from cells of temperature sensitive unsaturated fatty acid auxotrophs of Escherichia coli (K-12 UFAts) grown at 28°C (PL28), and at 42°C in the presence of 2% KCl as an osmotic stabilizer (PL42 (KCl)). From the analysis of fatty acids, it was shown that the content of unsaturated fatty acids of PL42 (KCl) is only 9% of the total fatty acids, while that of PL28 is 54%. The thermal phase transitions of the bilayers prepared from the phospholipid fractions were studied by proton magnetic resonance. The line widths of the methylene signals and the sums of the methylene and methyl signal intensities were plotted against reciprocal values of absolute temperature 1/T or temperature itself. From the plots phase transitions were detected at about 19°C for PL28 and at 43°C for PL42 (KCl). In spite of its complex composition of fatty acids a highly cooperative transition was observed in the case of PL42 (KCl). It was also suggested that the phospholipids bilayers in the biomembranes of this strain at the growth temperature (42°C) are in the state where the gel and liquid crystalline phases coexist.  相似文献   
15.
Summary The dnaA gene product of Escherichia coli, identified as a weakly basic protein of about 48,000 daltons (Yuasa and Sakakibara 1980), can be separated from other celluar proteins by means of two-dimensional gel electrophoresis. Synthesis of the dnaA protein took place continuously during a cell growth cycle. The newly synthesized dnaA protein persisted stably for one generation. Thermosensitive dnaA protein produced by the dnaA167 mutant was stable at 30° C, but was disintegrated at 42° C. The amount of intact dnaA protein present in the mutant exposed to the high temperature for 60 min was less than a quarter of the amount at the time of the shift. The cells having the reduced amount of intact dnaA protein were capable of initiating a new round of chromosome replication at the low temperature without de novo synthesis of the dnaA protein. The potential of the mutant for initiation of DNA replication decreased with reduction in the amount of the thermoreversible dnaA protein. The mutations dnaA167 and dnaA46 had no significant effect on the syntheses of the dnaA mRNA and the protein product at the low and high temperatures.Abbreviations used SDS sodium dodecyl sulfate - kb kilobase pairs - TCA trichloroacetic acid  相似文献   
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Using a highly specific and sensitive radioimmunoassay for dynorphin(1-13), dynorphin-like immunoreactivity (dynorphin-LI) was detected in rat pituitary and hypothalamus. Gel chromatographic studies on Sephadex G-50 revealed three components of dynorphin-LI with molecular weights of approximately 7500-9500 (big dynorphin), 3500-5500 (intermediate dynorphin) and 1600-1900 (small dynorphin), the latter of which eluted at the same position as authentic dynorphin contamination in porcine ACTH extracts (Sigma). Dynorphin-LI in rat anterior pituitary existed mainly as big dynorphin, whereas dynorphin-LI in rat intermediate-posterior pituitary and hypothalamus eluted mainly at the position of authentic small dynorphin.  相似文献   
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19.
Serum thyroid hormone concentrations, 1-thyroxine (T4), free T4 and 3,5,3'-l-triiodothyronine (T3) were measured in 213 patients of diabetes and analyzed their correlation with metabolic parameters, hyperglycemia and body weight. Haemoglobin A1 (HbA1) was used as an index of hyperglycemia. Body weight was expressed by relative body weight (body weight/standard weight). Among the thyroid hormones, only T3 had significant correlation with HbA1 and body weight (r = -0.476, P less than 0.01 and r = 0.369, P less than 0.01, respectively). Multivariable analysis of serum T3 by HbA1 and relative body weight gave the following regression equation. Serum T3 (ng/dl) = 108 + 0.362 x relative body weight (%) - 3.88 x HbA 1 (%). Though relative body weight had inverse correlation with HbA1, the contribution of the two metabolic parameters to the serum T3 was independent from each other. Our results confirm the previous reports that low T3 in diabetes correlates with severity of hyperglycemia and we report for the first time that serum T3 of diabetic patients has positive correlation with body weight, probably due to still available carbohydrate in spite of disturbances in the metabolism.  相似文献   
20.
The improved methods for the preparation of valency hybrid hemoglobins, (α3+β2+)2 and (α2+β3+)2 were presented. The (α3+β2+)2 valency hybrid was separated from the solutions of partially reduced methemoglobin with ascorbic acid, by using CM 32 column chromatography. The (α2+β3+)2 valency hybrid was also isolated from hemoglobin solutions, which were partially oxidized with ferricyanide, by chromatography on CM 32 column. These valency hybrid hemoglobins were found to be single on isoelectric focusing electrophoresis. Present procedures are very simple and are suitable for the bulk preparation of (α3+β2+)2 and (α2+β3+)2 valency hybrids.  相似文献   
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