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排序方式: 共有507条查询结果,搜索用时 109 毫秒
51.
目的:经胸超声心动图指导下应用国产Amplatzer封堵器介入治疗先天性心脏病,分析其应用价值。方法:选择2005-05/2007-03在成都市第三人民医院应用国产Amplatzer封堵器进行介入治疗的先天性心脏病患者59例,其中膜周型室间隔缺损30例,继发房间隔缺损15例,动脉导管未闭14例,所有患者均知情同意。①所有Amplatzer封堵器均由北京形状记忆合金材料有限公司提供。仪器采用Sequoia256及Sequoia512型彩色多普勒诊断仪,探头频率为2.5~5.0MHz。②在经胸超声心动图及X射线的引导下采用国产封堵器行先天性心脏病介入封堵术,术后1d,7d、1个月、3个月、1年随访,观察封堵器的位置,有无残余分流。结果:59例患者均封堵成功,全部进入结果分析,无脱落。2例膜周型室间隔缺损患者微量残余分流在术后3个月完全消失;其余患者均未见封堵器脱落、移位,无溶血、房室传导阻滞、瓣膜反流、心脏穿孔等严重并发症。结论:经胸超声心动图可用于引导先天性心脏病的封堵器介入治疗,同时也可用于术后随访,观察封堵器封堵后的移位、脱落等物理学变化。 相似文献
52.
The authors studied the natural history of human immunodeficiency virus (HIV) exposure in 187 hemophiliacs followed for an average of 45 months. Overall, 55 percent developed antibody specific for HIV and 21 percent developed persistent generalized lymphadenopathy. Most patients seroconverted sometime between early 1982 and the end of 1984. Four patients developed acquired immune deficiency syndrome (AIDS) and four seropositive patients developed idiopathic thrombocytopenia (ITP). One of the four patients who developed AIDS and three of the four with ITP had preexisting lymphadenopathy. None of the 10 patients with lymphadenopathy or the 20 asymptomatic patients was seropositive for human T-lymphotropic virus, type I. Although seropositivity and lymphadenopathy have been found in many of the authors' patients, few have developed clinical disease that can be related to HIV infection. 相似文献
53.
瘢痕疙瘩家系Fas基因的突变:2个家系10份标本分析 总被引:1,自引:0,他引:1
目的:观察瘢痕疙瘩家系样本中Fas基因有无突变,探讨Fas基因突变在瘢痕疙瘩形成中的意义。方法:实验于2005-01/05在上海基康公司完成。①标本来自南方医科大学南方医院整形外科2005年收集的A和B两个瘢痕疙瘩家系,所有参与观察的家系成员均签署知情同意书。②采用聚合酶链反应及基因测序技术,分别以A家系两例患者的瘢痕疙瘩组织为观察对象,以其周围正常皮肤及外周静脉血作为自身对照;其配偶的外周静脉血作为正常对照。并以B家系中两例患者的外周静脉血作为不同家系间的对照。共取10份样本,4份组织样本,6份静脉血标本。检测10份样本中Fas基因外显子1~9的基因序列。结果:①基因测序发现所检测的10个瘢痕疙瘩家系标本Fas基因的1~8外显子均未发现突变。②2份瘢痕疙瘩组织标本在第9外显子编码区的11bp,53bp两个位点上存在单个碱基的基因突变或多态性改变。结论:瘢痕疙瘩Fas基因外显子9区段的基因结构异常极有可能造成Fas蛋白的功能改变,从而导致身体局部瘢痕疙瘩的形成。 相似文献
54.
The clinical symptoms of Chagas disease are highly variable and are correlated with geographical distribution and parasite genetic group. Trypanosoma cruzi group I is associated with chagasic cardiomyopathy in Colombia and other countries in northern South America. However, in southern South America, T cruzi group II predominates and is associated with cardiomyopathy and digestive forms of the disease. The aim of this work was to determine the correlation between the genetic profiles of T cruzi groups circulating in the biological cycle and those present in tissues from patients with Chagas disease. We genotyped T cruzi in 10 heart tissue samples from patients with cardiomyopathy from a highly endemic area of Colombia. The genotyping was performed using nuclear and mitochondrial genes and low-stringency single-specific primer polymerase chain reaction. As expected, the predominant genetic group was T cruzi group I; however, we also detected T cruzi group II. Microsatellite analyses suggested a predominance of monoclonal populations, and sequence alignments showed similarities with Colombian strains. In addition, kinetoplast DNA signatures obtained by low-stringency single-specific primer polymerase chain reaction allowed us to group strains into the 2 genetic groups. Thus, we conclude that both T cruzi genetic groups are producing severe cases of Chagas disease in Colombia. We did not observe any correlation between low-stringency single-specific primer polymerase chain reaction profiles, histopathologic findings, clinical forms, and severity of Chagas disease. 相似文献
55.
The safety factor (SF) for neuromuscular transmission varies across limb muscles of different fiber-type composition. Using intracellular recordings in rat diaphragm fibers, we found that SF varies across muscle fiber types (even within a single muscle), being larger for type IIx or IIb fibers than for type I or IIa fibers. Fiber-type differences in activation history or mechanical load may contribute to differences in SF and are important determinants of neuromuscular plasticity. 相似文献
56.
C. Lahoz J.M. Mostaza S. Tranche R. Martin-Jadraque M.T. Mantilla I. López-Rodriguez B. Monteiro M.A. Sanchez-Zamorano M. Taboada 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2012,22(2):103-108
Background and aimsPatients with stable coronary heart disease (CHD) and atherogenic dyslipidemia (AD) have a high-risk of recurrence and are those who derive most benefit from treatment with lipid-lowering agents. The aim of this study was to examine the prevalence of AD in patients with stable coronary heart disease and to investigate associated factors.MethodsCross-sectional study involving 7823 subjects admitted for a coronary event between 6 months and 10 years previously. AD was considered to be the concurrent presence of low HDL-cholesterol (<1.03 mmol/L [40 mg/dL] in males, <1.29 mmol/L [50 mg/dL] in females) and elevated triglycerides (≥1.7 mmol/L [150 mg/dL]).ResultsMean age was 65.3 (10.1) years, 73.6% were males and 80.3% were receiving treatment with statins. Low HDL-cholesterol was observed in 26.3% of the participants, 39.7% had elevated triglyceride concentration and 13.0% had AD. The percentage of AD in patients with criteria for metabolic syndrome was 30.9%. Factors associated directly and independently with the presence of AD in the multivariate analysis were female sex, history of coronary syndrome without ST elevation or coronary revascularization, presence of atrial fibrillation, body mass index, LDL-cholesterol, systolic blood pressure and blood glucose levels, while age and glomerular filtration rate were significantly and inversely associated with AD.ConclusionA significant proportion of patients with coronary disease could benefit from interventions aimed at increasing HDL-cholesterol and reducing triglycerides. 相似文献
57.
R Ruiz-Salmerón E Ponce de León A López R Guitián D Romeo V del Campo R Mantilla J Pasalodos 《Revista espa?ola de cardiología》1999,52(9):671-680
INTRODUCTION AND OBJECTIVE: Tomography with acquisition synchronized with electrocardiography, gated-tomography, allows the assessment of left ventricular contractile function. The accuracy of a new method of gated-tomography, based on the three dimensional representation of the left ventricle to calculate the ejection fraction was validated by means of comparison with contrast ventriculography. METHODS: We studied 85 patients with ischemic cardiopathy, and ejection fraction was calculated by contrast ventriculography and sestamibi-gated-tomography, at rest and throughout 10 micrograms/kg/min of dobutamine. Furthermore, we assessed the extent of perfusion defect, as well as the number of segments with activity below 50% of the total 13 segments in which the tomographic slices were divided. RESULTS: Gated-tomography was significantly correlated to contrast ventriculography in the calculation of ejection fraction, both with acquisition at rest (r = 0.80) and throughout Dobutamine (r = 0.82). The average underestimation of gated-tomography calculation of ejection fraction was significantly greater for the rest study (-0.12 [IC 95% 0.04, -0.30]) than the dobutamine study (-0.07 [IC 95% 0.09, -0.24]). Patients with greater perfusion defects (4 o more segments) had no differences in underestimation of ejection fraction (-0.13 [IC 95% 0.03, -0.30] versus -0.11 [IC 95% 0.07, -0.29]). CONCLUSIONS: The three-dimensional method of gated-tomography accurately assesses the ejection fraction. The underestimation determined by this method was lower in the study done with viable doses of dobutamine. The extent of perfusion defect had no deleterious effect on gated-tomography in the calculation of ejection fraction. 相似文献
58.
59.
Trabecular bone architecture in female renal allograft recipients-- assessed by computed tomography 总被引:1,自引:0,他引:1
Grotz WH; Mundinger FA; Muller CB; Rasenack J; Schulte-Monting J; Langer MF; Schollmeyer PJ 《Nephrology, dialysis, transplantation》1997,12(3):564-569
BACKGROUND: Osteopenia with decreased bone mineral density (BMD) is a
frequent finding in renal allograft recipients. Data concerning the bone
architecture in these patients do not exist, however. METHODS: We compared
the bone architecture of 33 randomly assigned women (age 49 +/- 12 years),
who had received renal allografts 5.6 +/- 5.3 years before the
investigation, with 74 women (age 50 +/- 14 years) who were admitted for
osteodensitometry. All patients underwent single-energy computed tomography
(SEQCT) and a midvertebral high-resolution tomography with
computer-assisted analysis of the trabecular vertebral body architecture.
RESULTS: Progressive alteration of bone architecture was associated with
increasing vertebral height loss of the vertebral body. Height reduction of
a vertebral body of more than 15% was associated with a significantly lower
BMD (-2.3 +/- 0.8 versus -1.1 +/- 1.1 standard deviations below normal
BMD), a lower trabecular bone area (13 +/- 8% versus 42 +/- 22%) and a
lower trabecular diameter (1.4 +/- 0.5 mm versus 2.2 +/- 0.8 mm) compared
to recipients without height reduction. In comparison to a matched group of
patients with similarly reduced BMD (1.1 +/- 1.2 versus 1.2 +/- 1.1 SD
below normal BMD), renal allograft recipients showed a lower number of
trabecular plates (5.6 +/- 3.1 versus 7.0 +/- 3.7) and a smaller
intertrabecular surface (54 +/- 116 mm versus 75 +/- 138 mm). CONCLUSIONS:
Alterations of bone architecture in renal allograft recipients were
associated with progressive vertebral height loss. Despite similar bone
mineral density, differences of bone architecture could be observed between
renal allograft recipients and patients with osteoporosis.
相似文献
60.
Differentiation of thrombi from slow flow in the pulmonary arteries, sometimes observed in the presence of pulmonary arterial hypertension, can be equivocal. Magnetic resonance (MR) imaging was performed in a patient with chronic pulmonary thromboembolism and pulmonary arterial hypertension using an electrocardiographically gated technique that allowed visualization of the pulmonary arteries at the end of diastole and multiple times during systole. These images were compared with those of a patient with primary pulmonary hypertension and those of healthy subjects. Thrombi were discrete structures, seen throughout the cardiac cycle on both the first and second spin-echo images, and decreased in signal intensity on the second image. Slow flow increased in signal intensity and changed in structure during the cardiac cycle and was seen best on the second image. MR may play an important role in excluding large central thrombi as the cause of pulmonary arterial hypertension. It is a noninvasive method for defining pulmonary arterial wall thickness and for direct visualization of chronic pulmonary thrombus. 相似文献