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The following case reports represent two examples using the newly released Dilating Guide Wire. The balloon-wire system is specifically designed to be used as a steerable percutaneous transluminal coronary angioplasty (PTCA) guide wire. It can be utilized as a predilatation device in combination with a standard PTCA dilating balloon or as a free-standing dilatation catheter. As applied to the following situations, predilatation proved to be an effective time- and step-saving approach when confronting severely stenosed coronary artery lesions. 相似文献
94.
Interleukin-2 treatment potentiates induction of oral tolerance in a murine model of autoimmunity. 总被引:6,自引:1,他引:5
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L V Rizzo N E Miller-Rivero C C Chan B Wiggert R B Nussenblatt R R Caspi 《The Journal of clinical investigation》1994,94(4):1668-1672
The present study addresses the feasibility of potentiating oral tolerance by immunomanipulation, using the murine model of experimental autoimmune uveoretinitis (EAU) induced by immunization with the retinal antigen interphotoreceptor retinoid binding protein (IRBP). Three feedings of 0.2 mg IRBP every other day before immunization did not protect against EAU, whereas a similar regimen of five doses was protective. However, supplementing the nonprotective 3x regimen with as little as one injection of 1,000 U of human recombinant interleukin-2 (IL-2) resulted in disease suppression that was equal to that of the protective 5x regimen. The protective effect was maintained across a range of IL-2 doses and times of administration; none of the IL-2 regimens tested resulted in disease enhancement. Peyer's Patch cells of 3x-fed and IL-2-treated mice showed greatly increased production of TGF-beta, IL-4, and IL-10 compared with animals given the nonprotective 3x regimen and to animals given the protective 5x regimen. We propose that IL-2 treatment enhances protection from EAU at least in part by stimulating production of antiinflammatory cytokines by regulatory cells in Payer's Patches. Moreover, the observed lymphokine production patterns suggest that whereas protection induced by the 3x + IL-2 regimen is likely to involve antiinflammatory cytokines, protection induced by the 5x regimen might involve anergy or deletion of the uveitogenic T cells. These results could have practical implications for use of IL-2 as a safe and effective way of potentiating oral tolerance. 相似文献
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Hepatitis A Virus 总被引:1,自引:0,他引:1
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Janice C Probst Sarah B Laditka Jong-Yi Wang Andrew O Johnson 《BMC health services research》2007,7(1):40
Background
Travel burden is a key element in conceptualizing geographic access to health care. Prior research has shown that both rural and minority populations bear disproportionate travel burdens. However, many studies are limited to specific types of patient or specific locales. The purpose of our study was to quantify geographic and race-based differences in distance traveled and time spent in travel for medical/dental care using representative national data. 相似文献100.
We have determined a critical period for vestibular development in zebrafish by using a bioreactor designed by NASA to simulate microgravity for cells in culture. A critical period is defined as the briefest period of time during development when stimulus deprivation results in long lasting or permanent sensory deficits. Zebrafish eggs were collected within 3 hours of being laid and fertilized. In experiment 1, eggs were placed in the bioreactor at 3, 24, 30, 36, 48, or 72 hours postfertilization (hPF) and maintained in the bioreactor until 96 hPF. In experiment 2, eggs were placed in the bioreactor immediately after they were collected and maintained in the bioreactor until 24, 36, 48, 60, 66, 72, or 96 hPF. Beginning at 96 hPF, all larvae had their vestibulo-ocular reflexes (VOR) evaluated once each day for 5 days. Only larvae that hatched from eggs that were placed in the bioreactor before 30 hPF in experiment 1 or removed from the bioreactor later than 66 hPF in experiment 2 had VOR deficits that persisted for at least 5 days. These data suggest a critical period for vestibular development in the zebrafish that begins before 30 hPF and ends after 66 hPF. To confirm this, zebrafish eggs were placed in the bioreactor at 24 hPF and removed at 72 hPF. VORs were evaluated in these larvae once each day for 5 days beginning at 96 hPF. These larvae had VOR deficits that persisted for at least 5 days. In addition, larvae that had been maintained in the bioreactor from 24 to 66 hPF or from 30 to 72 hPF, had only temporary VOR deficits. In a final experiment, zebrafish eggs were placed in the bioreactor at 3 hPF and removed at 96 hPF but the bioreactor was turned off from 24 hPF to 72 hPF. These larvae had normal VORs when they were removed from the bioreactor at 96 hPF. Taken as a whole, these data support the idea that there is a critical period for functional maturation of the zebrafish vestibular system. The developmental period identified includes the timeframe during which the vestibular primary afferent neurons are born, innervate their central and peripheral targets, and remodel their central projections. 相似文献