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101.
MRI evaluations of intramyocardial hemorrhage in acute infarction have relied on T(2) and T(2)(*) shortening only. We propose a more comprehensive evaluation of hemorrhagic infarction based on the concept that fluctuations in T(2) and T(1) relaxation in acute reperfused infarction will reflect transient edema and hemoglobin oxidative denaturation to uncompartmentalized methemoglobin. Anteroapical infarction was created via percutaneous balloon in young swine (22-25 kg, N = 12). T(2), T(1), diastolic wall thickness (DWT), and the Gd-DTPA partition coefficient (lambda) were measured on days 0, 2, and 7. DWT was elevated at 1 hr postreperfusion (128% +/- 53%, P = 0.0001), and alleviated on days 2 and 7 (48% +/- 10%, P = 0.008; 53% +/- 24%, P = 0.003). T(2) and T(1) elevations were coincident with early edema (DeltaT(2) = 55% +/- 24%, P < 0.0001; DeltaT(1) = 27% +/- 18%, P < 0.04). T(2) and T(1) were nearly normal on day 2 (DeltaT(2) = 8% +/- 8%, P = 0.27; DeltaT(1) = 0% +/- 1%, P = 0.65). On day 7, T(2) increased while T(1) decreased (DeltaT(2) = 27% +/- 16%, P = 0.005; DeltaT(1) = -14% +/- 10%, P = 0.02). Lambda was elevated by >150% at all time points (P < or = 0.002). Histology verified hemorrhagic injury. T(1) and T(2) fluctuations are consistent with transient edema, as well as hemoglobin oxidative denaturation to decompartmentalized methemoglobin. This methodological development may broaden our understanding of hemorrhagic microvascular injury and improve its detection in clinical populations.  相似文献   
102.
目的分析左右肝管同时狭窄的高位胆管梗阻病例行胆管内双支架放置治疗的临床应用价值。资料与方法29例肝门部胆管梗阻患者,单支架放置13例,双支架放置16例。结果单、双支架放置成功率分别为100%、93.75%(P〉0.05);术后胆红素下降率分别为58.10%、74.63%(P〈0.05);6个月、1年的生存率分别为78.82%、38.43%和88.17%、45.16%(P〈0.05);并发症发生率为19.77%、23.10%(P〉0.05)。结论左右肝管同时狭窄的高位胆管梗阻,双支架放置治疗比单支架放置治疗能更有效地解除黄疸,延长生存期,值得临床推广应用。  相似文献   
103.
The posterior urethral valve uropathy: Results of treatment   总被引:2,自引:0,他引:2  
Nineteen children treated for posterior urethral obstruction due to congenital valve in the University of Benin Teaching Hospital, Benin City, Nigeria, over a 9-year period have been analysed. Their ages ranged from birth to 12 years. Results show that associated kidney pathology may be irreversible even after successful excision of the valve. This determines the final prognosis, which is worse the younger the child at presentation.  相似文献   
104.
105.
Summary The importance of the premaxillary position, size and shape in the development of the face and nose is discussed. The anthropological development of the premaxilla is studied. These factors are to be considered when cleft lip repairs are being planned and developed. Several cases are presented and discussed.  相似文献   
106.
目的:探讨诱导型一氧化氮合酶(iNOS)在单侧输尿管梗阻(UUO)大鼠术侧肾脏的表达.方法:建立左侧输尿管梗阻模型(UUO组),设假手术组为对照.3 d后应用逆转录-聚合酶链反应(RT-PCR)检测iNOS的mRNA水平.结果:与对照组相比,UUO组大鼠肾脏出现明显病理变化,并且其iNOS mRNA表达明显增加.结论:iNOS参与UUO的发生和发展的病理过程.  相似文献   
107.
Cardiac malignant mesenchymoma is an extremely rare malignancy with poor prognosis. We report a patient presenting with a history and clinical findings typical of mitral stenosis. Transthoracic echocardiography showed a mass on the thickened posterior mitral leaflet. Transoesophageal echocardiography revealed two tumoural masses: one on the atrial side of the posterior mitral leaflet causing mitral obstruction, the other arising in the region of the right lower pulmonary vein orifice and obstructing inflow through this vein.  相似文献   
108.
植入镍钛记忆合金支架治疗恶性胆道梗阻的临床分析   总被引:2,自引:0,他引:2  
目的 评价植入镍钛记忆合金支架治疗恶性胆道梗阻的疗效。方法 对16例恶性胆道梗阻患者。采用经手术及介入方法植入镍钛记忆合金胆道支架。结果 术后1个月内死亡1例,15例黄疸完全解除。随访15例,12例术后平均生存13.1个月。结论 植入镍钛合金胆道支架可提高姑息切除的疗效;对不能切除病灶患者,支架植入可解除黄疸,改善生活质量。  相似文献   
109.
The aim of this retrospective study of a cohort of 1787 consecutive kidney transplantations was to analyze the risk factors associated with the occurrence of ureteral stenosis and the impact of ureteral stenosis on graft and patient survival. Between January 1990 and December 2002, 1787 renal transplantations were performed at our center. Only stenosis observed after the first month, were considered. Among the parameters studied were: donor age and serum creatinine before procurement; recipient age, cold ischemia time, delayed graft function (DGF), number of arteries and the presence of a double J stent. The follow-up parameters were the number and timing of acute rejection episodes, cytomegalovirus (CMV) infection, acute pyelonephritis, renal function and death. Ureteral stenosis occurred in 4.1% of patients and was correlated with donor age > 65 years (p = 0.001), kidneys with more than 2 arteries (p = 0.009) and DGF (p = 0.016). Ureteral stenosis did not affect 10-year patient and graft survival rates, which were respectively 90% and 64% for the stenosis group, 86% and 63% for the no-stenosis group (p = NS). These data suggest an important role for donor age, number of renal arteries and DGF for the occurrence of ureteral stenosis following renal transplantation.  相似文献   
110.
The aim of this study is to evaluate the changes in Doppler resistive index (RI) and plasma creatinine and magnesium concentrations after unilateral ureteral obstruction in a rabbit model. Fourteen adult female rabbits were used in this study. In seven rabbits, the left ureter was ligated with silk suture, and the control group was sham operated. Before surgery and on the second and seventh days after surgery, blood samples were obtained to measure plasma creatinine and magnesium concentrations. Doppler RIs of both kidneys were also measured before surgery and on the second and seventh days after the surgical procedure. With regard to magnesium levels, there was a significant within-subjects sessions difference [F(2, 20) = 15.21, P= 0.001] indicating a decrease through sessions. Magnesium concentrations decreased significantly at the postoperative second and seventh days compared to preoperative baseline levels (P= 0.003 and P= 0.001, respectively). Multifactorial analysis of variance was applied for each session separately with laterality, and groups as factors. The Doppler RI and the creatinine level did not show any significant differences or interactions for all sessions (P > 0.05). The decreasing plasma magnesium concentration after surgery may indicate ureteral injury; however, Doppler studies and creatinine levels may not be useful as well.  相似文献   
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