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11.
维生素D衍生物联合供者骨髓细胞输注诱导异基因大鼠心脏移植免疫耐受 总被引:3,自引:2,他引:1
目的 探讨同种异基因心脏移植后免疫耐受的诱导。方法 建立大鼠颈部异位心脏移植模型,按分组分别给予门静脉输注供者骨髓细胞(DBMC)(B组)、骨化三醇灌胃(C组)、输注DBMC及骨化三醇灌胃(D组)以及环孢素A(CsA)灌胃(E组)。观察移植心脏的存活时间及心肌组织病理改变,测定心肌组织中肿瘤坏死因子及细胞间粘附分子-1 mRNA的表达以及血清钙、磷浓度,进行受者与供者及无关第三品系大鼠脾细胞混合淋巴细胞培养(MLR)。结果 D组移植心脏的存活时间较其它各组显著延长(P<0.05);术后7d,C组、D组、E组受者脾细胞均能显著抑制供者及第三方无关供者脾细胞作为刺激细胞引起的MLR;D组手术前后血磷、血钙浓度的差异无显著性(P>0.05);各组急性排斥反应的程度,D组最轻;D组肿瘤坏死因子及细胞间粘附分子-1 mRNA的表达受到显著抑制,与对照组(A组)、B、C组比较,差异有显著性(P<0.05)。结论 骨化三醇灌胃联合DBMC输注可显著延长移植心脏的存活时间,二者具有协同作用。 相似文献
12.
目的 提高对肾移植术后并发大腿感觉功能障碍的认识水平。方法 对179例肾移植术后患者进行问诊和大腿皮肤针刺检查。结果 179例中发现28例存在手术侧大腿感觉功能障碍。其中78例移植肾动脉与髂内动脉吻合的患者中有11例,分别为大腿前面7例、外侧面2例、前面和外侧面2例:101例移植肾动脉与髂外动脉吻合的患者中有17例,分别为大腿前面13例、外侧面1例、前面和外侧面3例。除1例为持续性感觉功能障碍外,其余27例均在术后半年内自愈。结论 肾移植术后出现手术侧大腿皮肤感觉功能障碍是较常见的并发症。肾移植术前应告知患者可能出现这种并发症。 相似文献
13.
目的探讨不同方法治疗压疮的临床效果。方法将65例患者计Ⅱ~Ⅲ度溃疡84处按基本条件相当原则随机分成A、B、C三组,A组21例28处,伤口采用清创冲洗后,给予康惠尔水胶体敷料;B组23例30处,伤口采用湿润烧伤膏;C组21例26处,清创冲洗后,给予自制凡士林油纱敷料外敷溃疡面处。结果B组愈合率最高,且平均显效时间和愈合时间均较A、C两组明显缩短,且A、B组明显高于C组。结论采用清创冲洗后用湿润烧伤膏是治疗压疮较好的方法之一。 相似文献
14.
BACKGROUND: Surgery on digit and nail requires a clear bloodless field that is often achieved by a tourniquet. OBJECTIVE: The objective is to present a simple, effective, and safe tourniquet for digital surgery. MATERIALS AND METHODS: A latex glove and a nylon zip-tie were used. A long strip is cut from the little finger tube of a latex glove. This is used for wrapping around the digit for exsanguination. The pressure is then maintained with a household nylon zip-tie. The finger strip is then cut to expose the operative field ready for surgery. The tourniquet pressure can be adjusted by tightening or loosening of the nylon zip-tie. RESULTS: Exsanguination and a bloodless field can be effectively achieved. The long tail of the nylon zip-tie reminds the operator to remove it at end of the surgery. CONCLUSION: A latex strip and nylon zip-tie combo serves as a simple, effective, and safe tourniquet for digital surgery. 相似文献
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MARYANN NOCERA T. MING CHU 《American journal of reproductive immunology (New York, N.Y. : 1989)》1995,33(4):282-291
PROBLEM : Human seminal plasma is known to exhibit immunosuppressive activity. Transforming growth factor β (TGF-β) has been identified as an immunosuppressive factor in human seminal plasma. Biologically active TGF-β represents a family of 25-kDa homodimeric proteins linked with disulfide bonds. TGF-β associates with high molecular weight proteins noncovalently to form a type of latency that is biologically inactive. Quantitative distribution of active form of TGF-β versus inactive latent form of TGF-β, and mechanism of the TGF-β activation in human seminal plasma remain to be elucidated. PURPOSE : To characterize seminal plasma latent form of TGF-β, including its concentration, and the mechanism underlying the activation of TGF-β. METHOD : Gel filtrations on ACA-34 and Biogel P-60 were used to fractionate seminal plasma. TGF-β was measured by enzyme immunoassay using antibodies specific for TGF-β1 and TGF-β2, respectively. Radioreceptor assay with recombinant human [125I]-TGF-β1 was applied to qualitatively identify TGF-β1. Kinetic experiments with various pH, temperature and time, along with protease inhibitors, were performed to delineate the activation mechanism of latent TGF-β. RESULTS : Human seminal plasma contained both TGF-β1 and TGF-β2, predominantly in latent form. The total concentration of TGF-β1 averaged 238 ng/ml versus an average of 18 ng/ml for TGF-β2. The in vitro activation or release of TGF-β1, from latent TGF-β1 was achieved only at acidic pH of <4.0, and was time and temperature dependent. At pH 3.7 and 37°C, a significant activation of latent TGF-β1 was achieved after an incubation of only 15 min, reached the maximum at 120 min, and the activated TGF-β1 remained relatively stable for at least 24 h. The activation was not inhibitable by a series of protease inhibitors examined, alone or in combination (e.g., phenylmethylsulfonyl fluoride, E-64, pepstatin, leupeptin, ethylenediamine tetraacetic acid). Competitive radioreceptor assay established the functional identity of TGF-β1 in human seminal plasma with recombinant human TGF-β1. CONCLUSION : Human seminal plasma TGF-β is biologically activated from high molecular weight latent TGF-β by acid pH. The acidic environment of female lower genital tract could represent an in vivo physiological condition for activation of seminal plasma TGF-β that may immunologically protect the integrity of sperm. 相似文献
17.
Signal transduction of many intracellular events is initiated by a minute influx of calcium ions into the cells, resulting in the formation of calcium-calmodulin complex and cAMP. Because zinc appears to have an inhibitory effect on a number of tissue reactions, it is postulated that this occurs through modulation of intracellular calcium influx. To test the hypothesis that the inhibitory effects of zinc are mediated through the calcium calmodulin-cAMP pathway, zinc was administered by various routes to five groups of nude mice (control, intragastric, intraperitoneal. intradermal and oral groups), and calmodulin and cAMP concentrations were measured in the cytosol of epidermal cells. Calmodulin levels decreased significantly in the groups given intraperitoneal zinc (P>0.025) and intradermal zinc (P>0.001) injections. Significant elevations of cAMP levels were noted with intradermal zinc (P>0.025). Overall, the relationship between calmodulin and cAMP appeared to be inversely logarithmic, with the lowest calmodulin levels associated with the highest cAMP concentrations. In addition, there was a significant trend towards a smaller calmodulin/cAMP ratio in all zinc-treated groups, except the mice fed dietary zinc. These results appear to correlate with tissue zinc levels obtained with these various forms of zinc administration. Our results therefore indicate that there is a reciprocity between epidermal calmodulin and cAMP levels, which may be modulated by external factors such as zinc. 相似文献
18.
肝移植术后早期黄疸的原因分析 总被引:3,自引:1,他引:2
目的 探讨肝移植术后早期黄疸的原因。方法 回顾性分析87例肝移植患者术后早期黄疸发生的原因及临床特征。结果 87例患者中,术后46例(52.87%)发生黄疸,共发生21种并发症,有17种(80.95%)并发症伴发黄疸,导致黄疸发生的常见原因依次为缺血.再灌注损伤(n=25,28.73%)、胆道并发症(n=23,26.44%)、急性排斥反应(n=19,21.84%)、药物性肝损害(n=4,4.60%)、移植肝病毒感染(n=4,4.60%)、腹腔内或全身严重感染等(n=3,3.45%),有2例(2.30%)原因不明;46例中,部分病例同时存在多个原因。不同原因所致的黄疸,在发生时间、胆红素水平的变化等方面均呈现相应的特征。结论 黄疸是肝移植术后早期较常见的临床表现,导致黄疽的原因复杂,甄别其主要原因,对指导治疗至关重要。 相似文献
19.
目的 探讨食管癌颈部吻合术中前壁单层吻合的临床应用价值 ,并与同期荷包状食管胃吻合法 (前壁双层吻合法 )相比较。方法 对 32 1例食管癌行根治性切除及食管胃颈部吻合术 ,其中前壁双层吻合 16 1例 ,前壁单层吻合16 0例。结果 双层吻合术中 ,吻合口瘘 5例 (3.13% ) ,随访 137例 ,吻合口直径 <0 .5 cm者占 5例 (3.5 % ) ,0 .5 - 1cm者70例 (5 0 .9% ) ,1cm以上者 6 2例 (4 5 .6 % ) ,单层吻合术中 ,吻合口瘘 7例 (4 .38% ) ,随访 131例 ,吻合口直径 <0 .5 cm者无 1例发生 ,0 .5 - 1cm者 5 3例 (4 0 .8% ) ,>1cm以上者 78例 (5 9.2 % )。结论 食管癌颈部吻合术中 ,前壁单层吻合能减少吻合口狭窄 ,改善术后病人的生活质量 ,而吻合口瘘发生率无明显增加。 相似文献
20.