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31.
Bacterial quinones were analysed by two-dimensional thin-layer chromatography with ready-made, multi-phase silica gel plates which allowed good separation of complicated quinone mixtures. A combination of this method and silver-ion-modified thin-layer chromatography made it possible to identify partially hydrogenated quinones.  相似文献   
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Metastatic variants of human prostatic adenocarcinoma cell lines (DU-145, LNCaP, and ND-1) were studied by using soft agar colony forming efficiency, nude mice tumorigenicity, in vitro invasion assay, and type IV collagenase assay. The DU-145 and ND-1 cell line showed higher metastatic potential than LNCaP. Lipids from DU-145, ND-1, and LNCaP cells were extracted and analyzed by thin-layer chromatography and gas-liquid chromatography. The major lipids were phosphatidylcholine, phosphatidylethanolamine, sphingomyelin, fatty acids, and cholesterol. The sphingomyelin level was significantly higher in highly metastatic cells (DU-145 and ND-1) compared with the lower metastatic variant (LNCaP). The increase in the synthetic pathway and decrease in degradation pathway of sphingomyelin in microsomal fractions was sufficient to account for the measured increase in sphingomyelin in DU-145 cells compared with LNCaP cells. The major fatty acids of these lipids were palmitic (16:0), stearic (18:0), oelic (18:1), and arachidonic acid (20:4). The arachidonic acid level was significantly decreased in DU-145 and ND-1 compared with LNCaP cells. Electron microscopic studies showed no significant changes in the morphology of DU-145, ND-1, and LNCaP cells. The results of these investigations demonstrate for the first time that sphingomyelin and arachidonic acid contents are different in high and low metastatic variants of human prostatic adenocarcinoma cell lines.  相似文献   
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G Sarkar  H S Yoon  S S Sommer 《Genomics》1992,13(2):441-443
We describe dideoxy fingerprinting (ddF), a hybrid between dideoxy sequencing and SSCP that can detect the presence of single base and other sequence changes in PCR-amplified segments. As implemented herein, ddF involves a Sanger sequencing reaction with one dideoxynucleotide followed by nondenaturing gel electrophoresis. When ddF was used to examine segments of the human factor IX gene, 84 of 84 different mutations were detected with a very low rate of false positive signals. The approximate locations of the sequence changes could be determined from the ddF pattern and samples with different sequence changes had different fingerprints. In addition, large segments could be amplified and rapidly screened by ddF in multiple smaller subsegments. The patterns observed with ddF are instructive in that they suggest an inherent limitation in the detection of certain mutations by SSCP.  相似文献   
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We describe oviposition and maternal behavior in the sawfly Cephalcia isshikiiand examine the adaptive significance of this behavior. Females deposited eggs in a single but loose cluster on needles of terminal twigs of spruces, Piceaspp., and remained with the eggs usually on the underside of the twig facing toward the tip. The female attended her eggs until death without taking food but did not follow the first-instar larvae that moved from natal needles even if she survived until then. When the female was disturbed, she usually moved toward the source and attempted to bite it. Though at much lower frequencies, this aggressive behavior was also observed in gravid females and even in males. Field observations and female removal experiments indicated that the female enhanced the survival of the eggs through the reduction of arthropod prédation.  相似文献   
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Serum IgE levels in rats infected with Paragonimus westermani]   总被引:1,自引:0,他引:1  
Paragonimus westermani is a common fluke in Korea. The present study aimed to determine serum total IgE and specific IgG levels in experimental paragonimiasis of rats. Each Wistar rat was inoculated orally with 20-25 metacercariae of P. westermani from Cambaroides similis. Before and after infection (1, 2, 3, 4, 6, 8 weeks) of P. westermani, the blood was collected from the retro-orbital venous plexus of rats and kept serum at -70 degrees C. Serum total IgE and specific IgG levels were determined by the capture and conventional enzyme-linked immunosorbent assay, respectively. The results were as follows; 1. Serum IgE values were increased to 0.18 +/- 0.042 at 2 weeks, 0.28 +/- 0.151 at 4 weeks and 0.43 +/- 0.055 at 8 weeks after infection. The absorbances of non-infected rats ranged 0.07 +/- 0.021-0.12 +/- 0.025. 2. Specific IgG values were slightly increased at 3 weeks (0.20 +/- 0.032) and gradually increased up to 8 weeks (0.31 +/- 0.067) after infection. The absorbances of non-infected rats ranged 0.11 +/- 0.035-0.18 +/- 0.019. The present results suggested that P. westermani could elevate serum IgE and specific IgG antibodies in Wistar rats which were not a good definitive host.  相似文献   
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A single-stage two-flap method of total ear reconstruction   总被引:2,自引:0,他引:2  
A single-stage two-flap method of total ear reconstruction in congenital microtia is reported. This method was derived from the one-stage reconstruction described by Song and Song. Two flaps defined by vascular basis were elevated on the mastoid area: the superficial skin flap supplied mainly by subcutaneous pedicled arteriole perforators from the posterior auricular artery and the deeper axial-pattern fascial flap including the posterior auricular artery itself. The ear framework, exaggeratedly carved using autologous rib cartilage, could be inserted easily between the two flaps, simultaneously producing the auriculocephalic angle and the conchal wall. Intraoperative expansion of the skin flap and postoperative external ear molding also were performed to create aesthetically pleasing ears.  相似文献   
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