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Prostaglandin E1 (PGE1) has therapeutic value for transplantations due to its microvascular activity. Interleukin (IL)-18, which is elevated in plasma during the acute rejection after organ transplantation, elicits the expression of intercellular adhesion molecule (ICAM)-1, B7.1, B7.2, CD40, and CD40 ligand (CD40L) on monocytes as well as the production of interferon (IFN)-gamma and IL-12 and proliferation of T-cells during the human mixed lymphocyte reaction (MLR) in an in vitro model of acute rejection. In contrast, PGE1 inhibits all the adhesion molecule expression, cytokine production and T-cell proliferation in the presence of IL-18. The effects of PGE1 depend on stimulation of the IP/EP2/EP4-receptor, and thus, PGE1 might have therapeutic potential for treating acute rejection due to its immune regulatory effect.  相似文献   
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Vestibular evoked myogenic potentials (VEMP) occurring after click stimulation in cervical muscles are thought to be a polysynaptic response of otolith-vestibular nerve origin. In optokinetic after-nystagmus (OKAN) the direction of after-nystagmus changes and slow-phase velocity decreases with head tilt. This phenomenon may be an otolith response to the direction of gravity. We assumed that intense clicks might have some influence on OKAN via the otolith-vestibular nerve. Twelve normal subjects who showed VEMP at 75 dB normal hearing level (nHL) clicks were examined. The OKAN was recorded under four conditions: right monaural, left monaural and binaural stimulation by 75 dB nHL clicks, and absence of click stimulation. Horizontal optokinetic stimulation was applied using stepwise increasing speeds from 30 deg/s to 90 deg/s. Two seconds before the stimulus ended, clicks were sounded. The slow-phase velocity of the recorded electro-nystagmography was manually measured. There was no effect on OKAN with unilateral stimulation but binaural stimulation suppressed it. These results suggest that a velocity storage integrator is influenced by intense clicks via the otolithic area. Received: 17 November 1999 / Accepted: 30 May 2000  相似文献   
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The method for subtracting the initial image from the localization image was evaluated for radioimmunoscintigraphy of tumors with technetium-99m (Tc-99m) labeled antibodies. Monoclonal antibodies were parental mouse and mouse-human chimeric antibodies to carcinoembryonic antigen (CEA), designated F11-39 and ChF11-39, respectively, both of which have been found to discriminate CEA in tumor tissues from the CEA-related antigens. After reduction of the intrinsic disulfide bonds, these antibodies were labeled with Tc-99m. In vivo studies were performed on athymic nude mice bearing the human CEA-producing gastric carcinoma xenografts. Though biodistribution results showed selective and progressive accumulation of Tc-99m labeled antibodies at the tumor site, high radioactivity in blood was inappropriate for scintigraphic visualization of the tumors within a few hours. We examined the subtraction of the initial Tc-99m image from the Tc-99m localization image after a few hours. Subtracted images of the same count reflected the in vivo behavior of the Tc-99m radioactivity. The subtracted scintigrams revealed excellent tumor images with no significant extrarenal background. Visualization of the tumor site was dependent on antigen-specific binding and nonspecific exudation. These results demonstrate that a method of subtraction of the initial image may serve as a potentially useful diagnostic method for an abnormal site for agents with a low pharmacokinetic value.  相似文献   
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Patients with advanced cervical cancers often have direct invasion of their carotid arteries. The prognosis for these patients with nonsurgical therapy is extremely poor. Because complete tumor removal is the only therapy that can offer these patients a chance for cure, carotid resection should be performed. We performed carotid resection and reconstruction on nine patients with advanced cervical cancers. Of these patients, none suffered from severe neurologic postoperative complications such as permanent hemiplegia. Three of the nine patients have been disease free for more than 24 months. These three patients would not have survived without carotid resection. Further study will show the usefulness of carotid resection and reconstruction in decreasing the morbidity and mortality in patients with cervical cancer involving the carotid artery.  相似文献   
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Highly purified beta-core fragment was obtained from urine of a pregnant woman with use of an immunoaffinity column. The amino acid sequence of beta-core fragment indicated that it is composed of two polypeptides linked by a disulfide bond. The two polypeptides correspond to the 6-40 and 55-92 portions of hCG beta-subunit. Both Asn13 and Asn30 residues were glycosylated. The N-linked sugar chains of beta-core fragment were quantitatively released as radioactive oligosaccharides by hydrazinolysis, followed by N-acetylation and NaB3H4 reduction. The radioactive oligosaccharides were fractionated by serial lectin column chromatography and Bio-Gel P-4 column chromatography, and their structures were investigated by sequential exoglycosidase digestion and periodate oxidation. The results indicated that they were a mixture of the four oligosaccharides: Man alpha 1----6(+/- Man alpha 1----3)Man beta 1----4GlcNAc beta 1----4(+/- Fuc alpha 1----6)GlcNAc. The structural characteristics of the sugar chains of beta-core fragment are quite different from those of the beta-subunit of hCG whose structures were typical biantennary sugar chains containing the Neu5Ac alpha 2----3Gal beta 1----4GlcNAc beta 1----2 group as their outer chains.  相似文献   
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