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71.
Receptors for IgM were detected on peripheral blood human eosinophils by a rosette technique with ox red blood cells coated with the IgM fraction of the specific immunserum. Between 14 % and 43 % (mean 27 %) FcµR positive cells were found after an overnight incubation period at 37°C by using this technique. The specificity of the receptors for IgM was assessed by studying the inhibitory capacity of purified human IgM in the rosette assay. From an ultrastructural point of view, the EAM rosette-forming cells are mature eosinophlic granulocytes characterized by a nucleus with a variable number of lobes and a certain number of «first type» granules partially or totally devoid of their content. 相似文献
72.
K. Takahashi N. Yamamoto H. Egawa T. Takeuchi T. Yamaguchi Y. Takada F. Nishizawa T. Takayasu M. Narita K. Mori Y. Yamaoka K. Ozawa 《Transplant international》1993,6(5):245-250
This study investigated whether prostaglandin E1 (PGE1) could reduce hepatic injury to the liver graft caused by harvesting and 24-h preservation in University of Wisconsin (UW) solution in a canine model. The PGE1-treated group was intravenously administered 0.5 g/kg per minute of PGE1 for 30 min before harvesting, as well as a concentration of 1 mg/l PGE1 in the washout and UW solutions. In both the PGE1-treated and the control group, all recipients survived for 1 week or more after transplantation. Arterial ketone body ratio (AKBR) remained over 1.0 in the early postoperative period. The PGE1 group showed significant reductions in guanase, GOT, and LDH during the early postoperative period compared to the untreated control group. Histological examination disclosed partial mitochondrial swelling, hepatocyte vacuolation, and necrosis in the control group, while such abnormalities were rarely seen in the PGE1 group. These results suggest that PGE1 can effectively reduce hepatic injury to liver grafts preserved in UW solution prior to transplantation. 相似文献
73.
74.
目的:研究复合应用高渗氯化钠溶液和琥珀酰明胶对失血性休克犬的血流动力学和氧转运的影响。方法:18只犬麻醉后气管内插管,自主呼吸空气。经股动脉放血至平均动脉压为6.7kPa并维持2h。分为3组,每组6只。氯化钠溶液组:于5min内输入失血量10%的75g·L-1NaCl;高渗氯化钠溶液/琥珀酰明胶组:于5min内输入失血量10%的75g·L-1NaCl/琥珀酰明胶;乳酸钠林格氏液组:于20min内输入2.5倍失血量的乳酸钠林格氏液。结果:3组的血流动力学参数在治疗后都有显著的改善。高渗氯化钠溶液/琥珀酰明胶对血流动力学和氧供的作用时间较HSC持久。高渗氯化钠溶液/琥珀酰明胶组的胶体渗透压明显高于其它两组。各组氧摄取率和血浆乳酸浓度无显著差异。结论:失血性休克早期应用小容量75g·L-1NaCl/琥珀酰明胶可改善血流动力学和氧供需平衡。 相似文献
75.
76.
INTRODUCTION Themethodofcoldliverpreservationisacruciallimit ingfactorinthedurationofliverpreservation .Experimentalevidencehasshownthatnonparenchymalcellsaremorevulnerabletohypothermicstoragethanhepatocyte,indicatingthatprotectionofthemicrovasculatur… 相似文献
77.
Elisa Guazzelli Elena Masotti Manfred Kriechbaum Frank Uhlig Giancarlo Galli Elisa Martinelli 《Macromolecular chemistry and physics.》2023,224(3):2200360
Amphiphilic fluorinated copolymers PEGMAx-co-FAy and TEGMAx-co-FAy are prepared by activators regenerated by electron transfer atom transfer radical polymerization (ARGET-ATRP). All polymers present a reversible thermoresponsive lower critical solution temperature-type behavior, and a cloud point temperature (Tc) in the range of 30–60 °C strictly dependent on the length of the oxyethylene side chain, the content of the hydrophobic counits, and the concentration of the solution. Combined small angle X-ray scattering (SAXS) and dynamic light scattering measurements are used to study the self-assembly behavior in water, organic solvents (tetrahydrofuran [THF] and dimethylformamide [DMF]), and a fluorinated solvent (hexafluorobenzene [HFB]). SAXS confirms the formation of compact-globular single-chain self-folded unimer micelles in water below Tc, which generally presents small hydrodynamic diameters (Dh ≤ 8 nm) as a result of the folding of the hydrophobic perfluorohexylethyl acrylate counits. The copolymers are also able to form reverse unimer micelle in HFB. The copolymers are not able to self-assemble in unimer micelles in THF or DMF solutions, in which they adopt conventional random coil conformations. 相似文献
78.
We evaluated three solutions used for preserving lungs, namely, University of Wisconsin (UW), Euro-Collins (E-C), and low potassium dextran (LPD), by measuring the high energy phosphates in the preserved lung tissue. The left lungs of Sprague-Dawley rats were excised and flushed with 5 ml of one of the solutions at 10°C through the pulmonary artery, after which they were deflated and immersed in the solution at 10°C for 24 h. The tissue adenosine triphosphate (ATP) concentration in mol/g tissue wet weight after 24 h of storage was 2.55 ± 0.48 (n = 7) in the UW lungs, 1.98 ± 0.25 (n = 6) in the E-C lungs, and 1.53 ± 0.32 (n = 4) in the LPD lungs, being significantly higher in the UW lungs than in either the E-C or LPD lungs (P < 0.05). The histopathological findings of the E-C lungs were more deteriorated, with marked interstitial edema, septal hypertrophy, and perivascular hyaline degeneration, than either the UW or LPD lungs. Thus, the findings of this study indicate the superiority of UW solution for lung preservation. 相似文献
79.
Bengtsson G.; Wallin A.; Sjoblom P.; Lindblom B. 《Human reproduction (Oxford, England)》1995,10(2):459-463
The objective of this study was to assess the ability of certaindrugs, used for local injection therapy of ectopic pregnancy,to suppress the activities of cultured human placental cells.Placental cells from legal first trimester abortions were preparedby collagenase treatment and density gradient centrifugation.The cells were exposed to hyperosmolar glucose (500 mg/ml),15-methyl-prostaglandin-F2 (15-m-PGF2; 107 to 103mol/l) and prostaglandin-F2 (PGF2; 105 to 5X103mol/l) for 30 min on days 24 after seeding. The effectson the secretion of human chorionic gonadotrophin (HCG) andprogesterone, as well as on the protein content per culturewell, were measured. Hyperosmolar glucose was the most effectivedrug and caused a marked decrease of the protein content inthe culture wells and a reduction of progesterone secretion.Of the two prostaglandins, only 15-m-PGF2 affected the viabilityof the cells and reduced the protein content of the wells. Theclinical effectiveness of the two groups of drugs seems to besimilar but certain in-vitro effects are different. Thus invivo they may act on different target tissues. Against thisbackground, the combination of hyperosmolar glucose and prostaglandinsmight be an interesting approach for local injection therapyfor tubal pregnancy. 相似文献
80.
Investigations were carried out by means of an autologous, heterotopic model for kidney transplantation applied to dogs. Duration of cold ischemia was 48 h. Four experimental groups were arranged. During the first 20 min following revitalization of the transplanted kidney, group 1 (HTK solution/80 cm perfusion height) showed a significant glomerular and tubular malfunction. In group 2 (HTK solution/120 cm perfusion height), only four urinary proteins with molecular weights of 25 kDa, 67 kDa, 100 kDa and >100 kDa were found. The excretion of higher molecular proteins receded over the 20-min period of observation. In both group 3 (HTK/aspartate solution) and group 4 (HTK/tryptophan solution) the quantity of excreted glomerular and tubular protein was well above that of group 2. As opposed to the Tryptophan group, a complete restoration of renal function was observed in the Aspartate group after 4 weeks. In general, the standard HTK protective solution delivered with 120 cm perfusion pressure gave the most favorable results, with the lowest levels of proteinuria and a satisfactory recovery of renal function after revitalization. 相似文献