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The serum levels of estradiol-17β, progesterone and HPL have been estimated by specific radioimmunoassay in thirty women undergoing abortion with 15-methyl-PGF given by intra-amniotic, extra-amniotic or intra-muscular route. A significant decline in the levels of these hormones was observed in 27 cases in which the pregnancy was terminated. However, in the remaining three cases, 15-methyl-PGF was found to be unsuccesful, and no significant change in the hormone levels was evident. The decline in these hormones was more marked by intra-muscular route, than that observed by the other routes. The pattern of estradiol-17β decline was more consistent when compared with progesterone and HPL. The levels of progesterone and HPL, in a few cases, rather showed an increase in the initial hours of 15-methyl-PGF administration before the decline began and this pattern was more prominent on extra-amniotic administration. In general, the decline in the hormone levels was slower in cases which took longer time for abortion than cases with shorter induction-abortion time (IAT).The decline in estradiol-17β levels was about 65 percent at six hour of intra-muscular administration of 15-methyl-PGF, whereas the corresponding fall with intra-amniotic and extra-amniotic routes was 29 and 22 percent, respectively. However, the net drop in its levels during IAT was not significantly different (range 70 to 80 percent) by the three routes. About 38 percent fall in progesterone levels was observed at six hour of intra-muscular administration whereas, by intra-amniotic the fall was 19 percent. The net decline in progesterone levels, during IAT, was in the range of 46 to 60 percent by the three routes. Similarly, intra-muscular 15-methyl-PGF evoked a sharper decline in HPL levels as compared with other routes. The total decline during IAT was 58 to 66 percent. The results, thus indicated that the abortion with 15-methyl-PGF was associated with a fall in the serum hormone levels, which could be resultant effect of alterations in the hormone production by the foeto-placental unit. This along with the uterine contractions may play a significant role in the abortifacient action of 15-methyl-PGF.  相似文献   
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Apparent values of Km and Vmax have been measured for catalysis of hydrolysis of unsonicated egg lecithin liposomes, activated through addition of 0.4 M n-hexanol, by phospholipases A2 from bee and snake venoms and by phospholipase C from Clostridium welchii as a function of the concentration of three surfactants: hexadecylamine, hexadecyltrimethylammonium bromide, and dihexadecyl phosphate. For all three enzymes, values of Km and Vmax show little or no dependence on the concentration of these ionic surfactants, demonstrating that the liposomal surface charge is not a crucial factor in determining susceptibility to phospholipase-catalyzed hydrolysis.  相似文献   
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Forty-four Vibrio cholerae isolates collected over a 7-month period in Chennai, India in 2004 were characterized for gene traits, antimicrobial susceptibility and genomic fingerprints. All 44 isolates were identified as O1 El Tor Ogawa, positive for various toxigenic and pathogenic genes viz. ace, ctxB, hlyA, ompU, ompW, rfbO1, rtx, tcpA, toxR and zot. Nucleotide sequencing revealed the presence of cholera toxin B of classical biotype in all the El Tor isolates, suggesting infection of isolates by classical CTXΦ. Antibiogram analysis showed a broad-spectrum antibiotic resistance that was also confirmed by the presence of resistant genes in the genomes. All isolates contained a class 1 integron and an SXT constin. However, isolates were sensitive to chloramphenicol and tested negative for the chloramphenicol resistant gene suggesting a deletion in SXT constin. Fingerprinting analysis of isolates by ERIC- and Box PCR revealed similar DNA patterns indicating the clonal dissemination of a single predominant V. cholerae O1 strain throughout the 2004 outbreak in Chennai.  相似文献   
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Plasmonics - We present enhancement of operational bandwidths of planar terahertz metasurfaces by incorporating a complex unit cell that consists of a pair of concentric ring resonators. The inner...  相似文献   
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Plasmonics - The present study focuses on the employment of TiO2 (titanium dioxide) film as an anti-reflective coating (ARC) on thin crystalline silicon (Si)-based solar cells along with the...  相似文献   
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MsrA, an efflux pump belonging to ATP‐binding cassette (ABC) transporter family that conferred resistance to macrolides, was detected in Staphylococcus aureus strains. Herein, we report the isolation of phytoconstituents from Piper cubeba fruit methanol extract and investigated their efflux pump inhibitory potential against S. aureus MsrA pump. Four isolated compounds, viz. pellitorine, sesamin, piperic acid and tetrahydropiperine studied in combination with erythromycin in S. aureus RN4220, exhibited 2–8‐fold reduction in minimum inhibitory concentration (MIC) of erythromycin. Pellitorine and sesamin decreased MIC of erythromycin by 8‐fold. The real‐time fluorometry‐based efflux and accumulation studies of ethidium bromide (EtBr) on S. aureus RN4220 in the presence of these compounds showed reduced efflux and enhanced uptake, thus indicating inhibition of the efflux pump. Pellitorine showed significant post‐antibiotic effect of erythromycin. The results revealed that the primary mechanism of action of these compounds involves steady ATP production impairment.  相似文献   
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