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731.
The internal organs of Ixodes ovatus and the ears of wild rodents (Apodemus speciosus, Eothenomys smithii) and an insectivore (Crocidura dsinezumi) were cultured to isolate borreliae; positive samples were examined for the distribution and dissemination of spirochetes in the host tissues using electron microscopy. Seven isolates were derived from the unfed ticks and the three species of mammals. These isolates were identified as Borrelia japonica judging from the outer surface protein profile using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and reactivity to a B. japonica-specific monoclonal antibody. Borreliae were found only in the midgut lumen of the tick in close contact with the microvilli on the midgut epithelium; on the other hand, borreliae found in the ears of the mammals existed freely in the collagenous intercellular substances of connective tissues or in close contact with fibrocytes. The ultrastructural disparities between the borreliae in ticks and mammals appeared to correspond to differences in motility. Interestingly, the borrelia which invaded through the perineurium appeared to contact the basement membrane of a Schwann cell that enclosed several nonmyelinated nerve fibers. This may offer important information regarding the involvement of the nervous system in Lyme disease. 相似文献
732.
R Sakakibara Y Yokoo K Yoshikoshi N Tominaga K Eida M Ishiguro 《Journal of biochemistry》1987,102(5):993-1001
To determine the subcellular sites for synthesis and processing of human chorionic gonadotropin subunits in cells, first trimester placental cells were fractionated subcellularly on sucrose density gradients. Analysis of the subcellular fractions by immunobinding techniques revealed that the rough endoplasmic reticulum-rich fraction contained only intermediates having high-mannose oligosaccharides, but the Golgi-rich fraction contained not only intermediates but also mature forms which were resistant to endoglycosidase H but sensitive to neuraminidase. These results show that human chorionic gonadotropin subunits are synthesized in the rough endoplasmic reticulum as forms containing high-mannose oligosaccharides, and their maturation occurs in the Golgi apparatus by trimming with endogenous glycosidases. They are then modified by addition of complex oligosaccharides and terminal sialic acid through glycosyltransferases. 相似文献
733.
Phosphoglucose isomerase electrophoretic patterns of the Japanese quail were found to be controlled by three alleles at an autosomal locus. In the laboratory quail population, the frequency of the alleles PGIF , PGIS1 and PGIS2 was 0.175, 0.465 and 0.360, respectively. 相似文献
734.
We demonstrated the homogenous simultaneous detection of HCV RNA and internal control by two-color fluorescence real-time monitoring of isothermal sequence amplification with INAF probes. 相似文献
735.
736.
737.
Shigeru Nanno Masatsune Ishiguro Gunki Funatsu Masaru Funatsu 《Bioscience, biotechnology, and biochemistry》2013,77(8):1645-1650
Ricin D, a toxic protein from castor bean, was found to contain 6 moles of glucosamine and 17 moles of mannose per mole of protein.Isolation of two constituent polypeptide chains, namely Ala-chain and Ile-chain, and subsequent proteolytic digestions with Nagarse and Pronase revealed two glycopeptides (Asp1 Thri Gly1 glucosamine2 mannose6 and Asp1 Thr1 Glu1 Pro1 glucosamine2 mannose7) from Alachain and one (Asp1 Ile1 Phe1 glucosamine2 mannose4) from lie-chain. The total carbohydrate content of these glycopeptides accounts for all that of the whole protein. It is therefore that carbohydrate moieties are covalently linked to the polypeptide chains in three sites to form this glycoprotein. 相似文献
738.
Replantation of major extremities after long periods of ischemia can lead to viable replants in many cases, but functional restoration is often poor owing to fibrosis of the muscle. In this study, maximum hypothermic time in tissue transfers containing skeletal muscle using hindlimbs of Lewis rats preserved in 4 degrees C Euro-Collins solution was investigated. After preserving midthigh amputated legs in this solution for 6, 9, and 12 hours, the legs were transplanted to other inbred rats using microsurgical technique, and 1 week later, gastrocnemii were obtained to analyze ATP, ADP, and AMP using high-performance liquid chromatography. The values were compared with those for healthy legs, nonischemic operated control legs, and legs preserved in the same manner for 6, 9, and 12 hours. Histologic and serologic examinations were conducted. ATP values of the 9-hour preservation group resumed those of the nonischemic operated control group, with the values of the 12-hour preservation group remaining at 61 percent. Histologically, focal necrosis, hyaline degeneration, and regeneration processes were the most characteristic manifestations in the muscles transplanted after cold ischemia of 12 hours. It was concluded that skeletal muscle could be preserved for 9 hours in 4 degrees C Euro-Collins solution. 相似文献