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971.
972.
Similar inhibitory factors for DNA synthesis were found in fetal calf serum and a hemolymph of the moth,Bombyx mori. The factors were highly purified by gel filtration, ion exchange and thin layer chromatography and appeared to be heat-stable. They showed the same effects on some bacteria and mammalian cells. The significance of these DNA synthesis inhibitory 1 Kd peptides is discussed.  相似文献   
973.
Abstract The behavioral pattern of Vibrio parahaemolytics during the winter season (December 1988 to March 1989) in the water column, sediment, plankton and sinking particles was determined in a eutrophic marine environment. A total of 15 environmental parameters and seven microbial characteristics were examined. This halophile was isolated sporadically from bottom water and plankton materials, whereas it was undetectable in the surface water and sediment samples. However, V. parahaemolyticus was isolated from the sinking particles continuously throughout the sampling period with highest counts during February 1989. Out of 195 strains identified, 10 Vibrio spp. and 3 Listonella spp. were observed of which V. alginolyticus was predominantly isolated irrespective of the samples tested. Simple correlation and multiple regression analyses show that the occurrence of V. parahaemolyticus is not governed by any single biotic or abiotic factor of the environment. Possibly, the cumulative effect of all these environmental parameters on the distribution of V. parahaemolyticus is conceivable.  相似文献   
974.
Twenty-three strains of human diploid cells derived from embryonic lungs were tested for production of interferon by “superinduction.” Strain HAIN-55 produced a relatively high level of interferon. The optimal concentration of cycloheximide for superinduction was essentially equal to that reported with foreskin fibroblasts. On the other hand, actinomycin D at a concentration of 4 to 16 μg/ml enhanced the production of interferon more strikingly than at a concentration of 1 μg/ml, which was usually employed for superinduction in the foreskin fibroblasts. Inhibition of interferon production was observed when fetal bovine serum was added to the medium during treatment with metabolic inhibitors for superinduction. Minimal essential medium was superior to Eagle's basal medium as growth medium for interferon production, and serum added after removal of metabolic inhibitors could be replaced by bovine serum albumin. The yield of interferon produced under the best conditions in this study, with strain HAIN-55, was more than 10,000 reference units/ml.  相似文献   
975.
We have developed a new tool, called fastDNAml, for constructingphylogenetic trees from DNA sequences. The program can be runon a wide variety of computers ranging from Unix workstationsto massively parallel systems, and is available from the RibosomalDatabase Project (RDP) by anonymous FTP. Our program uses amaximum likelihood approach and is based on version 3.3 of Felsenstein'sdnaml program. Several enhancements, including algorithmic changes,significantly improve performance and reduce memory usage, makingit feasible to construct even very large trees. Trees containing40–100 taxa have been easily generated, and phylogeneticestimates are possible even when hundreds of sequences exist.We are currently using the tool to construct a phylogenetictree based on 473 small subunit rRNA sequences from prokaryotes.  相似文献   
976.
The methoxymethyl group of the 6-methoxy-2-methoxymethyl-3-(3,4-methylenedioxyphenyl)-1,4-benzodioxan-7-yl moiety of insecticidallignans of Phryma was modified with sereral alkyl groups to evaluate the effect on activity of the substituents. The assay results make it evident that this activity was significantly modified by the chain length or bulkiness of the alkyl groups and that the oxygen atom of the methoxymethyl group was fairly important for enhancing the activity.  相似文献   
977.
κ-casein A was fractionated into 9 subcomponents, all of which were identified as κ-casein from immunological analyses. The microheterogeneity of the subcomponents was explained by stepwise increase of their carbohydrate contents (0~4mol/mol of GalNAc, and 0~8mol/mol of NANA). The micelle-stabilizing ability of κ-casein subcomponents increased with the increase of their carbohydrate contents: the carbohydrate rich subcomponent 7 possessed twice the stabilizing ability of the carbohydrate free subcomponent 1. The sensitivity of synthetic casein micelle composed of κ-casein subcomponents and αsl-casein to the wheat germ lectin-induced aggregation also increased with the increase of their NANA contents.  相似文献   
978.
Recently, photodynamic therapy using 5-aminolevulinic acid (ALA-PDT) has been widely used in cancer therapy. ALA administration results in tumor-selective accumulation of the photosensitizer protoporphyrin IX (PpIX) via the heme biosynthetic pathway. Although ALA-PDT has selectivity for tumor cells, PpIX is accumulated into cultured normal cells to a small extent, causing side effects. The mechanism of tumor-selective PpIX accumulation is not well understood. The purpose of the present study was to identify the mechanism of tumor-selective PpIX accumulation after ALA administration. We focused on mitochondrial labile iron ion, which is the substrate for metabolism of PpIX to heme. We investigated differences in iron metabolism between tumor cells and normal cells and found that the amount of mitochondrial labile iron ion in cancer was lower than that in normal cells. This finding could be because of the lower expression of mitoferrins, which are the mitochondrial iron transporters. Accordingly, we added sodium ferrous citrate (SFC) with ALA as a source of iron. As a result, we observed the accumulation of PpIX only in tumor cells, and only these cells showed sensitivity to ALA-PDT. Taken together, these results suggest that the uptake abilities of iron ion into mitochondria play a key role in tumor-selective PpIX accumulation. Using SFC as a source of iron might thus increase the specificity of ALA-PDT effects.  相似文献   
979.
Fetal movement is an important biological index of fetal well-being. Since 2008, we have been developing an original capacitive acceleration sensor and device that a pregnant woman can easily use to record fetal movement by herself at home during sleep. In this study, we report a newly developed automated software system for analyzing recorded fetal movement. This study will introduce the system and compare its results to those of a manual analysis of the same fetal movement signals (Experiment I). We will also demonstrate an appropriate way to use the system (Experiment II). In Experiment I, fetal movement data reported previously for six pregnant women at 28-38 gestational weeks were used. We evaluated the agreement of the manual and automated analyses for the same 10-sec epochs using prevalence-adjusted bias-adjusted kappa (PABAK) including quantitative indicators for prevalence and bias. The mean PABAK value was 0.83, which can be considered almost perfect. In Experiment II, twelve pregnant women at 24-36 gestational weeks recorded fetal movement at night once every four weeks. Overall, mean fetal movement counts per hour during maternal sleep significantly decreased along with gestational weeks, though individual differences in fetal development were noted. This newly developed automated analysis system can provide important data throughout late pregnancy.  相似文献   
980.

Objectives

To evaluate the diagnostic value of a new photodynamic diagnosis (PDD) system using 5-aminolevulinic acid (ALA) for the diagnosis of bladder tumors. To validate whether false-positive findings caused by tangent effects in PDD can be resolved, we compared diagnostic accuracies between the new PDD system and a conventional PDD system.

Patients and Methods

Among 30 transurethral bladder biopsies, 15 cases received ALA-PDD using rigid fluorescence cystoscopy (conventional PDD system), and flexible fluorescence cystoscopy with a twin mode monitor (new PDD system) was used in a separate set of 15 cases. To evaluated the usefulness of ALA-PDD, diagnostic accuracies were retrospectively compared between the conventional PDD system and the new PDD system.

Results

Of 207 specimens from 30 cases, we obtained 110 specimens using the conventional PDD system and 97 specimens using the new PDD system. Of these samples, we selected 30 distal bladder specimens each from both the conventional PDD system and the new PDD system. The overall sensitivity, specificity and false-positive rate for the new PDD system were 100%, 82.6%, and 17.4%, respectively. Those of the conventional PDD system were 83.3%, 66.2% and 33.8%, respectively. The overall false-positive rate of the new PDD system improved to 16.4% when compared with the conventional PDD system. Furthermore, the false-positive rate of the new PDD system in distal bladder samples improved to 11.8%. The overall AUC of the new PDD system was significantly greater compared with that of the conventional PDD system (P<0.05). We obtained similar significant results in the distal bladder samples (P<0.05). All procedures were well tolerated by all patients without any severe adverse events.

Conclusion

Flexible cystoscopy had a significantly higher specificity and improved incidence of tangent effects when compared with conventional methods. This preliminary study suggests that the new PDD system using 5-aminolevulinic acid may be more useful than the conventional PDD system.  相似文献   
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