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21.
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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Maternal care in the red-headed spruce web-spinning sawfly,Cephalcia isshikii (Hymenoptera: Pamphiliidae) 总被引:1,自引:0,他引:1
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
25.
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
26.
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
27.
The F2 progeny of a cross between a chromosome 2 multiple marker stock and an adapted cultivar of barley were analyzed for four
morphological markers and electrophoretic patterns of eight leaf isozymes. TheIdh-2 locus was linked to thePer-5 locus (27.96±5.07 cM) and to thee locus (10.26±3.13 cM). Also, thePer-5 ande loci were located on the short arm of chromosome 2. In additionIdh-2 was also located on barley chromosome 2 and was linked to thev locus (13.18±3.56 cM), which is located on the long arm of chromosome 2. Two other marker genes,li andwst,,B, were linked (26.50±5.24 cM) on chromosome 2 but segregate independently of the other loci evaluated.
This project was supported by funds from the U.S.-Spain Joint Committee for Scientific and Technological Cooperation. 相似文献
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Heterogeneity of adrenocortical ferredoxin 总被引:1,自引:0,他引:1
Bovine adrenocortical ferredoxin (adreno-ferredoxin) was purified from adrenocortical mitochondria by an improved method that included hydrophobic chromatography on Toyopearl gels. The purified ferredoxin was electrophoretically homogeneous. It was further separated into five fractions by hydrophobic chromatography on a TSK-gel phenyl-5PW column with a high-pressure liquid chromatography system. The properties of the three main fractions were examined. The fractions had identical absorption spectra and almost the same activity in an NADPH-cytochrome c reducing system. Their amino-terminal sequences all corresponded to the reported sequence, but the carboxyl-terminal residues were glycine or serine, not alanine as reported. These results indicate that these adreno-ferredoxins had additional amino acid residues at the carboxyl end. It seems that adreno-ferredoxin extracted from mitochondria undergoes proteolytic attack during purification to become heterogeneous. 相似文献
30.
Disulfides of the lutropin receptor 总被引:1,自引:0,他引:1
Affinity cross-linking of the lutropin receptor with 125I-human choriogonadotropin (hCG) on porcine granulosa cells produced four distinct homone-receptor complexes under reducing conditions. They contain 18-, 24-, 28-, and 34-kDa components (Ji, I., Bock, J. H., and Ji, T. H. (1985) J. Biol. Chem. 260, 12815-12821). Photoaffinity labeling and cross-linking produced 136-, 102-, and 74-kDa hCG-receptor complexes under reducing conditions and the 136-kDa complex under nonreducing conditions. In addition, the unreduced 102-kDa complex was seen in photoaffinity labeling but not in cross-linking. When the unreduced 136-kDa complex was reduced, the 102- and 74-kDa complexes were generated, indicating release of the 34- and the 28-kDa components in two steps. When the unreduced 102-kDa complex was reduced, the 74-kDa complex was produced, indicating the release of a 28-kDa component. The 74-kDa complex could not be reduced but was cleaved by alkaline treatment to produce the hCG alpha beta dimer. The results indicate that the 24-kDa component is released from the 74-kDa complex, since the apparent mass of the hCG alpha beta dimer on gels is 50 kDa. The 24-kDa component appears to be the initial site for photoaffinity labeling or cross-linking and to be disulfide linked to the 28-kDa component which is in turn disulfide linked to the 34-kDa component. These intercomponent disulfides exist in some receptors but not all. Formation of the disulfide-linked 136-kDa band required the presence of a sulfhydryl-blocking agent, N-ethylmaleimide. In particular, the 34-kDa component was vulnerable to reduction. There was no significant evidence of disulfides between the hormone and any of the receptor components. 相似文献