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51.
BACKGROUND: Animals reconstituted with allogeneic whole bone marrow (WBM) are often tolerant of donor-specific solid organ grafts. Clinical application of bone marrow transplantation in solid organ transplantation has been limited, however, principally by graft-versus-host disease. We previously demonstrated that hematopoietic stem cells (HSCs) reconstitute lethally irradiated allogeneic mice without producing graft-versus-host disease. The purpose of this study was to determine whether tolerance to solid organ grafts could be induced in mice reconstituted with HSCs. METHODS: BALB/c mice were lethally irradiated and reconstituted with allogeneic C57BL/Ka, Thy-1.1 WBM or HSCs. An isolated group was given a limited number of HSCs (250 cells) and a subpopulation of allogeneic cells known to facilitate HSC engraftment (facilitators). C57BL/Ka, Thy-1.1 neonatal heart grafts were placed in reconstituted animals either at the time of hematopoietic transplant or 35 days later. Third-party C3H grafts were placed over 2 months after hematopoietic reconstitution. Tolerance was defined as the persistence of cardiac contraction for the duration of evaluation (125-270 days). RESULTS: All surviving mice that were reconstituted with C57BL/Ka, Thy-1.1 HSCs, WBM, or HSCs and facilitators were tolerant of C57BL/Ka grafts long-term. Third-party C3H grafts placed in reconstituted animals were rejected by day 12, whereas those placed in unmanipulated mice were rejected by day 9. CONCLUSION: These data indicate that tolerance to concurrently or subsequently placed solid organ grafts can be reliably achieved with limited numbers of purified HSCs in a model where immunocompetence to third-party major histocompatibility complex antigens is delayed but intact. 相似文献
52.
GJ Jhon JE Hong HJ Yoon GI Rhyu YH Kim JS Yoo YS Chang 《Canadian Metallurgical Quarterly》1996,38(5):879-887
The presence of octoxynol from dried bear-bile was examined. Octoxynol was coextracted when glycolipids by Folch-Suzuki partition method. Octoxynol formed mixed-micelles with glycosphingolipids. The glycolipids were purified by DEAE-Sephadex A-25 column chromatography. The fractions containing mixed micelles were obtained from linear gradient solvent of 0.05M-0.5M ammonium acetate in methanol. HPLC ( Bondapak-NH(2) - linked to a Bondapak-C(18) column) chromatogram showed five peaks. Two possible structures for the fourth peak fraction were proposed as (CH(3))(3)C-CH(2)-C(CH(3))(2)-C(6)H(4)-OR and (CH(3))(3)C-C(CH(3))(2)-CH(2)-C(6)H(4)-OR by NMR spectroscopy. The structure was further confirmed by electrospray tandem mass spectrometry (ESI MS/MS). The spectrum showed a protonated molecule at m/z 559 and three different series of ions with mass difference of 44 were detected in the MS/MS spectrum. Therefore, the structure of the fourth peak fraction from HPLC was confirmed as octoxynol, (CH(3))(3)C-CH(2)-C(CH(3))(2)-C(6)H(4)-(OCH(2)-CH(2))n-OH, based on mass spectrometry and NMR spectroscopy. 相似文献
53.
H Margolis-Nunno L Bardossy R Robinson E Ben-Hur B Horowitz MA Blajchman 《Canadian Metallurgical Quarterly》1997,37(9):889-895
BACKGROUND: Treatment of platelet concentrates (PCs) with psoralens and broad-band ultraviolet A (UVA) radiation is being examined for the elimination of pathogens that might be present in donated blood. Previous studies have demonstrated the inactivation of cell-free viruses and the maintenance of platelet integrity with common in vitro assays. STUDY DESIGN AND METHODS: Human immunodeficiency virus (HIV) in three forms-cell-free, activity replicating, and latently infected cell lines-was added to PCs and treated with 50-microgram per mL of 4'-aminomethyl-4,5',8-trimethylpsoralen (AMT), 0.35 mM rutin, and broad- and narrow-band UVA light (320-400 nm and 360-370 nm [UVA1], respectively). The inactivation of added HIV was assessed in tissue culture; platelet hemostatic activity was assessed in thrombocytopenic rabbits. RESULTS: Each form of HIV was inactivated completely (> or = 10(5) infectious units) on treatment with 30 J per cm2 of UVA1 light. Similar results were obtained on treatment of 2.5 mL of PCs in test tubes or intact PC units (50 mL) in blood bags. Latently infected cell lines were substantially more sensitive than cell-free HIV or HIV that was actively replicating. Human platelets treated with 40 J per cm2 of UVA1 light had a fully corrected bleeding time shortly after treatment or after 5 days' storage, as assessed in thrombocytopenic rabbits. Platelet hemostatic function began to decrease with 81 J per cm2 of UVA1 light and was abolished with 113 J per cm2. At similar fluences, broad-band UVA light was more injurious to platelets than was UVA1 light. CONCLUSION: HIV transmission might be eliminated by PCs after treatment with AMT and UVA1 light and without a reduction in platelet hemostatic function. 相似文献
54.
We compared the dose-response relationships of cisatracurium, mivacurium, atracurium, vecuronium and rocuronium and examined the interactions of cisatracurium with mivacurium, atracurium, vecuronium and rocuronium in humans by isobolographic and fractional analyses. We studied 180 adult patients during nitrous oxide-fentanyl-propofol anaesthesia. Neuromuscular block was monitored using mechanomyography to detect the twitch response of the ulnar nerve at the wrist. The dose-response curves were determined by probit analysis. The calculated ED50 values and their 95% confidence intervals were 40.9 (38.1-43.7), 49.8 (47.0-52.6), 187.2 (175.1-199.3), 36.6 (34.7-38.5) and 136.4 (129.2-143.6) micrograms.kg-1 for cisatracurium, mivacurium, atracurium, vecuronium and rocuronium, respectively. Corresponding ED95 values were 57.6 (53.5-61.7), 91.8 (88.1-95.5), 253.1 (238.9-267.3), 52.9 (49.1-56.7) and 288.7 (276.2-301.2) micrograms.kg-1, respectively. The interaction between cisatracurium and mivacurium, vecuronium or rocuronium was found to be synergistic, but the interaction between cisatracurium and atracurium was found to be additive. Synergy between cisatracurium and vecuronium or rocuronium was greater than between cisatracurium and mivacurium. 相似文献
55.
A receiver targeting OC-48 (2.488 Gb/s) serial data link has been designed and integrated in a 0.8-μm CMOS process. An experimental receiving front-end circuit demonstrates the viability of using multiple phased clocks to overcome the intrinsic gate-speed limitations in the demultiplexing (receiving) and multiplexing (transmitting) of serial data. To perform clock recovery, data is 3× oversampled so that transitions can be detected to determine bit boundaries. The design of a transmitter for the high-speed serial data is also described. The complete transceiver occupies a die area of ~3×3 mm2 相似文献
56.
Presents general criteria for observation room windows. Various glazing materials available for proper lighting and the typical transmission and reflection characteristics of each, acoustical factors relating to sound control, and general design considerations are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
57.
58.
M. Mottaghi P. Lang F. Rodriguez A. Rumyantseva A. Yassar G. Horowitz S. Lenfant D. Tondelier D. Vuillaume 《Advanced functional materials》2007,17(4):597-604
Self‐assembled monolayers (SAMs) are molecular assemblies that spontaneously form on an appropriate substrate dipped into a solution of an active surfactant in an organic solvent. Organic field‐effect transistors are described, built on an SAM made of bifunctional molecules comprising a short alkyl chain linked to an oligothiophene moiety that acts as the active semiconductor. The SAM is deposited on a thin oxide layer (alumina or silica) that serves as a gate insulator. Platinum–titanium source and drain electrodes (either top‐ or bottom‐contact configuration) are patterned by using electron‐beam (e‐beam) lithography, with a channel length ranging between 20 and 1000 nm. In most cases, ill‐defined current–voltage (I–V) curves are recorded, attributed to a poor electrical contact between platinum and the oligothiophene moiety. However, a few devices offer well‐defined curves with a clear saturation, thus allowing an estimation of the mobility: 0.0035 cm2 V–1 s–1 for quaterthiophene and 8 × 10–4 cm2 V–1 s–1 for terthiophene. In the first case, the on–off ratio reaches 1800 at a gate voltage of –2 V. Interestingly, the device operates at room temperature and very low bias, which may open the way to applications where low consumption is required. 相似文献
59.
60.