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81.
Delayed graft function (DGF) in cadaver kidney transplants is a common problem and is often due to acute tubular necrosis (ATN). DGF in transplants may have a deleterious effect on long-term graft survival. Since thyroid hormone has been shown to hasten recovery from ATN in experimental models, we designed a trial to determine if a defined course of triiodothyronine (T3) would improve the short- or long-term outcome of patients with DGF in cadaveric transplants. A prospective, randomized, placebo controlled, double blind trial of T3 was carried out in patients with DGF in cadaveric renal transplants. End-points were percentage requiring dialysis, percentage recovering function, time to recovery and length of hospital stay. Long-term outcomes were percentage grafts functioning at 1 year and mean serum creatinine at 1 year. Forty-four patients were randomized to receive either T3 or placebo. Three patients were dropped from each group when early biopsies disclosed that DGF was due to rejection. The groups were well matched by age, cold ischemia time of the graft, and percentage reactivity to a random panel of antigens. Baseline thyroid function studies, including T3, reverse T3 (rT3), and thyroid stimulating hormone (TSH) levels, were similar between the two groups and typical of 'euthyroid-sick syndrome'. T3 had no effect on percentage requiring dialysis, time to recovery, percentage recovering function, or length of stay. At 1 year follow-up, graft function was similar in both groups and significantly lower than that seen in patients with good initial function. Thyroid hormone, given early in the course of DGF in cadaver kidney recipients, had no effect on the course of DGF. Long-term graft function is impaired in patients who experience post-transplant DGF compared to those who have good initial function.  相似文献   
82.

Objectives

For individuals not on antiretroviral therapy, the risk of heterosexual transmission of HIV appears negligible when blood plasma (BP) viral loads are <1500 HIV‐1 RNA copies/mL. It is not clear whether this observation can be extrapolated to individuals on highly active antiretroviral therapy (HAART). Because of differential tissue penetration, antiretroviral drug concentrations may be sufficient to maintain an undetectable viral load in the BP yet not achieve adequate levels to suppress HIV in the genital tract. Therefore, we wanted to correlate HIV viral loads and drug concentrations in semen plasma (SP) and BP.

Methods

Thirty‐three men were included. All were on combination antiretroviral therapy with an undetectable BP viral load for at least 1 year. Blood and semen samples were collected within 2 h of each other and tested for HIV RNA by the NucliSens QT (bioMerieux, St Laurent, QC, Canada) method; drug concentrations were determined by liquid chromatography tandem mass spectrometry.

Results

Two of the 33 patients (6.1%) with BP viral loads below detection had time‐matched HIV viral loads in SP ≥700 copies/mL. Both patients were on efavirenz, the SP concentrations of which were ≤10% of the levels in BP and well below the minimal therapeutic drug monitoring target concentration required to suppress HIV.

Conclusions

Because, at least in part, of poor drug penetration into the genital tract, an undetectable HIV viral load in the BP does not guarantee an undetectable viral load in semen. In view of this, caution should be taken in concluding that patients on HAART with suppressed viraemia are sexually non‐infectious.  相似文献   
83.
Lesion evolution during focal cerebral ischemia may depend on flow restrictions or on accumulation of toxic mediators within the infarct and expansion of these factors to the periinfarct region. So far, the precise contribution of flow dependent versus spreading-mediated impairment of viable periinfarct tissue has not been determined. Therefore, we measured lesion expansion, flow restrictions and glutamate distribution on serial brain sections at different time points after experimental focal ischemia.Permanent focal ischemia was induced by occlusion of the right middle cerebral artery in male rats and the flow reduction was subsequently measured at 1, 12 and 24 h using iodo[14C]antipyrine autoradiography. Additionally, the necrotic volume was determined on serial brain sections and the glutamate content was measured in tissue samples from adjacent microdissections.Twelve hours after focal ischemia no noteworthy viable areas with blood flow restrictions of 20-40 ml 100 g− 1 min− 1 existed but at 24 h the necrotic tissue exceeded the hemodynamically compromised region by 40 ± 21 mm3 (24%). Furthermore, at 12 and 24 h the glutamate content was elevated in areas surrounding the infarct.Relevant flow restrictions are detectable only during early stages of infarct maturation, whereas the propagation of secondary factors may be the predominant mechanism for delayed infarct evolution.  相似文献   
84.
产科危重患者多器官功能障碍综合征的临床分析   总被引:4,自引:0,他引:4  
目的 :分析产科危重患者多器官功能障碍综合征 (MODS)的发病特点及诱因 ,以及与急性生理与慢性健康状况评分II(APACHEII)的关系。方法 :回顾分析 2 0 0 0年1月至 2 0 0 4年 4月转入GICU产科危重患者中发生MODS 6 6例的临床资料 ,并计算其A PACHEII评分。结果 :产科MODS患者诱因主要是产科因素 ,共 4 8例 (72 .73% ) ,死亡 7例 (14 .5 8% ) ,以重度子痫前期或子痫及产后出血为主 ;诱因 18例妊娠合并内外科疾病 ,死亡 11例 ,死亡率为 6 1.11% ,以妊娠合并心脏病和妊娠合并重症肝炎为主。产科MODS患者死亡率随着器官损害数的增多而上升 ,差异有显著性 (P <0 .0 5 ) ;随着器官损害数的增多 ,APACHEII评分逐渐升高 ,差异有显著性 (P <0 .0 5 ) ;APACHEII评分用于预测MODS死亡阳性率 ,2 ,3,4 ,5个器官受损害 ,其阳性率分别为 33.4 5 % ,5 7.12 % ,97.0 9% ,10 0 %。结论 :产科多器官功能障碍 /衰竭的产科主要诱因是重度子痫前期 /子痫 ,产后出血 ;产科MODS患者死亡率也随着器官损害数的增多而上升 ;APACHEII评分可在一定程度上作为评定产科MODS患者病情危重程度和预测预后的指标。  相似文献   
85.
经大隐静脉穿刺置管溶栓治疗急性期髂股静脉血栓形成   总被引:3,自引:0,他引:3  
目的:探讨经大隐静脉入路置管溶栓治疗髂股静脉血栓形成的应用价值。方法:对18例急性期髂股静脉血栓形成的患者在下腔静脉滤器植入术前提下,经大隐静脉入路置管溶栓治疗。结果:18例患者经大隐静脉穿刺成功置管,技术成功率为100%,治疗有效率为100%。置管期间无不良反应及并发症发生;平均住院时间为12.5d。结论:经大隐静脉入路置管溶栓介入治疗急性期髂股静脉血栓操作简便,经济实用,安全有效。  相似文献   
86.
目的探讨大鼠脂肪来源间充质干细胞(MSC)对大鼠肝移植术后急性排斥反应的作用。方法分离、培养SD大鼠MSC,体外混合淋巴细胞培养(MLC)体系中,研究MSC对Wistar大鼠T细胞增殖的抑制作用。以SD与Wistar大鼠为供受体建立肝移植模型。随机分为MSC处理组与空白对照组,术后第7天检测肝功能、血清白细胞介素(IL)-2和白细胞介素(IL)-10水平、肝组织病理形态及肝细胞凋亡。结果体外MLC中,Wistar大鼠T细胞增殖明显受抑,抑制率为48.44%。实验组血清丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)、总胆红素(TBIL)、IL-2、IL-10分别为(134.2±45.0)、(162.5±30.5)U/L、(30.6±5.4)μmol/L、(187.35±18.26)、(193.95±37.62)μg/L;对照组上述指标分别为(355.6±54.3)、(296.4±71.2)U/L、(145.7±28.6)μmoL/L、(295.73±57.15)、(75.12±11.23)μg/L,两组差异有统计学意义(P<0.05);病检提示实验组排斥反应较对照组明显减轻;脱氧脲核苷酸缺口末端标记(TUNEL)检测提示实验组肝细胞凋亡程度明显低于对照组(P<0.05)。结论供体来源MSC能明显抑制MLC体系中受体源T细胞的增殖,并能显著减轻大鼠肝移植术后急性排斥反应。  相似文献   
87.
Although common carotid artery (CCA) occlusions are rare, acute clinical presentations vary from mild to devastating strokes primarily due to tandem occlusions in the intracranial arteries. Three patients with acute CCA occlusions were treated with systemic tissue plasminogen activator (TPA). Blood pressures were kept at the upper limits allowed with TPA therapy with fluid balance and the 'head-down' position. Recanalization occurred in intracranial vessels only. Marked early neurological improvement occurred in two of three patients. CCA occlusions should not be considered contra-indication to systemic thrombolysis.  相似文献   
88.
目的观察急性冠状动脉综合征患者介入治疗后血小板活化指标CD62p、CD63及糖蛋白Ⅱb/Ⅲa受体复合物及内皮功能的改变。方法60例急性冠状动脉综合征患者在冠状动脉介入术前和术后即刻以及次日采用流式细胞仪检测血小板活化指标CD62p、CD63及糖蛋白Ⅱb/Ⅲa受体复合物;双抗体夹心固相酶联免疫吸附试验测定血浆假血友病因子的表达水平;放射免疫测定法测定血浆内皮素1表达水平;酶法测定血浆一氧化氮的含量;彩色多谱勒超声诊断仪测量内皮依赖性血管舒张功能。选择健康体检者和稳定型心绞痛患者各30例作对照,观察急性冠状动脉综合征患者冠状动脉介入前后指标的变化并与对照组比较。结果与健康对照组和稳定型心绞痛组比,急性冠状动脉综合征组CD62p、CD63及糖蛋白Ⅱb/Ⅲa受体复合物明显增高(P<0.05或0.01);急性冠状动脉综合征患者介入术后即刻CD62p、CD63和糖蛋白Ⅱb/Ⅲa受体复合物与术前相比明显增高(P<0.01),但术后24h较术前无明显变化(P>0.05)。与健康对照组和稳定型心绞痛组比,急性冠状动脉综合征组假血友病因子、内皮素1的表达水平明显增高(P<0.01),内皮依赖性血管舒张功能和一氧化氮降低(P<0.05或<0.01);急性冠状动脉综合征患者介入术后即刻血浆假血友病因子和内皮素1水平升高(P<0.05或P<0.01),内皮依赖性血管舒张功能和一氧化氮水平降低(P<0.05),且介入术后24h假血友病因子水平也较术前升高(P<0.05),内皮依赖性血管舒张功能降低(P<0.05),但内皮素1和一氧化氮水平与术前差异无显著性(P>0.05)。结论血小板活化和内皮功能的损伤在急性冠状动脉综合征发生和发展过程中起重要的作用,冠状动脉介入术后血管内皮受到一定损伤,血小板有一定程度的激活。  相似文献   
89.
本文报告39例临床上除外右房肥大的P波高电压,此种P波高电压主要见于冠心病及急性颅脑疾患,二者之和占76.9%。其形态64%与肺性P波相同。产生的机制可能与结间束传导阻滞、中枢调节机能受累、交感神经兴奋性增高等有关。  相似文献   
90.
急性膀胱炎超声表现特点   总被引:3,自引:0,他引:3  
目的探讨急性膀胱炎(AC)的超声声像图特点。方法将32例AC自然充盈膀胱后的左右径、上下径、前后径,膀胱壁厚度、膀胱壁光滑度及膀胱内透声状态与63例正常组所测膀胱对应各值比较。结果炎症组与正常对照组膀胱左右径、上下径及前后径比较均无显著性差异,膀胱壁厚度炎症组(0.446±0.036)cm,对照组(0.224±0.036)cm,两者间有非常显著性差异P<0.01。尿频症状明显同时伴有血尿者,膀胱壁增厚的几率增加。结论膀胱壁增厚(以黏膜层为著),尿液透声差或透声欠佳是AC的主要超声征像。  相似文献   
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