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61.
心脏瓣膜置换术后中远期疗效分析 总被引:8,自引:0,他引:8
目的 分析探讨心脏瓣膜置换术的中远期疗效。方法 1978年至 2 0 0 1年 12月 ,行瓣膜置换手术 2 14 1例 ,同期随访 16 81例 ,计 80 2 1 1人·年 ,平均 4 77人·年。通过回顾病因、手术方式、瓣膜类型等因素 ,观察术后病人心功能改善情况 ,病死率及并发症等 ,采用t检验 ,多因素回归等统计学方法分析。结果 92例死亡。总体生存率 5年为 (92 3± 2 2 ) % ,10年生存率为 (90 1± 2 7) %。并发症有血栓栓塞、机械瓣膜功能障碍、瓣周漏、溶血、机械瓣膜感染性心内膜炎。术后心功能 (NYHA)与术前比较有明显的提高。结论 1.机械瓣置换术后中远期疗效满意 ,病死率及并发症均较低 ;与术前心功能和手术种类直接相关 ;2 .使用保留瓣下结构及三尖瓣成形术对术后心功能恢复有明显效果 ;3.术中良好心肌保护是提高手术成功率的关键。 相似文献
62.
目的:了解我国人群血浆高敏感性C反应蛋白(hs-CRP)水平与代谢综合征(MS)关系及其它影响hs-CRP水平的相关因素。方法:1198例血浆标本来自2006年3月~2006年11月在浙江省桐乡市第三人民医院体检人群。采用Beckm an LX20血生化全自动生化仪及其配套试剂,测定上述空腹血浆标本中血糖(FPG)、甘油三脂(TG)、总胆固醇(TC)、高密度脂蛋白胆固醇(HDL-c)、低密度脂蛋白胆固醇(LDL-c)和hs-CRP水平。MS诊断标准参照中华医学会推荐标准。采用SPSS13.0统计学软件,分析hs-CRP水平与MS关系及其它影响hs-CRP水平的相关因素。结果:男性hs-CRP水平(x±s=1.55±0.53)高于女性(x±s=1.32±0.56)(P<0.001)。15.3%被检者(183/1198)患有MS,其hs-CRP水平明显高于非MS者(P<0.001)。各MS判断指标中,分别有肥胖、高血压病、糖尿病、高TG、低HDL-c时,其hs-CRP水平也明显升高(P<0.001)。排除年龄、性别影响后,hs-CRP水平与MS显著相关(OR值2.18,P<0.001)。结论:hs-CRP水平与MS密切相关,hs-CRP水平增高可作为独立反映MS发生的标志性检测指标。 相似文献
63.
P. M. Parizel G. Rodesch D. Balériaux D. Zegers de Beyl J. D'Haens J. Noterman C. Segebarth 《Neuroradiology》1989,31(1):75-79
Summary The Gd-DTPA-enhanced magnetic resonance findings in two patients with herniated thoracic intervertebral discs are reported. The first patient was a 56-year-old woman with a small subligamentous T6-7 disc herniation, slightly lateralized to the right. The second patient was a 51-year-old man with a central and right posterolateral disc herniation, including a large calcified fragment, at the T8-9 level. The nonenhanced MR examination revealed the presence of an extradural mass lesion in both patients, impinging upon the dural sac and compressing and displacing the spinal cord posteriorly. The lesion was slightly hypointense on both T1- and T2-weighted spin echo sequences. Following intravenous injection of Gd-DTPA in a dosage of 0.1 mmol/kg body weight, enhancement of the posterior longitudinal ligament was noted and triangular areas of contrast uptake were seen to occur in the epidural space above and below the herniated disc. At surgery, they were found to correspond to dilated and congested epidural veins. 相似文献
64.
Stuart J. McLachlan John C. Francisco Joseph R. Pernicone Anton N. Hasso 《Journal of magnetic resonance imaging : JMRI》1994,4(3):405-411
A phase III multicenter study was conducted in 89 patients with known intracranial vascular lesions to evaluate an extracellular gadolinium contrast agent, gadoteridol, for intracranial magnetic resonance (MR) angiography. The pre- and postcontrast MR angiograms of 82 patients were evaluated by the unblinded investigators and by two blinded readers (A and B) for visualization of lesions; arterial and venous anatomy; extent, size, and number of lesions; and disease classification. The unblinded readers indicated that lesions were visualized better on postcontrast images in the following categories: venous anatomy, 87 (81%) of 107 lesions; arterial anatomy, 43 lesions (40%); and extent or size of lesions, 38 lesions (36%). In 29 (35%) of 82 patients, the unblinded readers determined that enhanced MR angiography provided more diagnostic information than unenhanced MR angiography. The blinded readers determined that enhanced MR angiography provided more information for visualization of vascular anatomy in more than 60% of cases. The additional information provided with gadoteridol would have changed the diagnosis in nine (8%) of 107 lesions seen by the unblinded readers, 11 (12%) of 90 lesions seen by reader A, and three (3%) of 93 lesions seen by reader B. The results confirm that the use of gadoteridol improves the visualization of intracranial vascular lesions with MR angiography. The authors conclude that development of new postprocessing algorithms will improve the utility of contrast-enhanced MR angiography. 相似文献
65.
Porcine models have been used extensively for skin flap research because of the established similarity between the cutaneous
blood supply of the swine and humans. The Yucatan minipig provides an excellent model for researching the properties of random
cutaneous flaps, offering several advantages over other breeds of swine. In this study, a total of 67 random cutaneous dorsal
flank flaps measuring 4 × 14 cm were raised on nine Yucatan minipigs. The mean survival length (10.03 ± 1.60 cm) of the nondelayed
flaps was greater than others reported in the literature. The well-defined plane between the subcutaneous tissue and the panniculus
carnosus facilitated flap elevation consistently above the level of the panniculus carnosus thereby ensuring the creation
of a true random cutaneous flap. Furthermore, the hairless nature of the skin, particularly beneficial in studying chemical
peels, permits easy visualization and monitoring of any external skin changes. These advantages make the Yucatan minipig a
more desirable alternative to other breeds of swine for use in skin flap research. 相似文献
66.
Romhild M. Hoogeveen Chris J. G. Bakker Max A. Viergever 《Journal of magnetic resonance imaging : JMRI》1997,7(2):321-330
A problem of current MRA techniques is the inability to accurately depict the vascular anatomy, particularly in areas of disturbed flow. Various reasons, such as intravoxel phase dispersion, saturation, temporal variations, and maximum intensity projection (MIP) nonlinearity, cause a wrong delineation of vessel boundaries. A phase contrast (PC)-based postprocessing operation, the phase derivative (PhD), is introduced to detect phase fluctuations indicating flow. Two-dimensional and three-dimensional angiographic reconstruction algorithms are presented. Mathematical formulas are derived to predict the effect of sampling to flow profiles and the effect on the PhD of these profiles. Numerical, phantom, and preliminary in vivo experiments demonstrate that PhD images do not suffer from phase wraps and allow a velocity dynamic range extension only limited by a differential phase change. It is also shown that PhD MIPs produce higher signal-to-noise ratios than conventional PC angiograms and give a better impression of the anatomy of (stenotic) vessels and of their diameters for both laminar and disturbed flow. 相似文献
67.
John E. Jordan Norbert J. Pelc Dieter R. Enzmann 《Journal of magnetic resonance imaging : JMRI》1994,4(1):25-28
Normal blood flow and velocity in the superior sagittal sinus were measured in 30 patients. A fast two-dimensional ungated phase-contrast (PC) pulse sequence was compared with a peripherally gated cine PC technique for velocity and flow quantitation. The same imaging parameters were used for both methods. Measured values for mean velocity and flow obtained with the two methods were compared by using regression analysis and t testing. For blood flow, the correlation coefficient was 0.976. For velocity measurements, r was 0.950. Mean flow was 285 mL/min ± 19 with the ungated PC method and 281 mL/min ± 19 with the cine PC method. The mean velocities measured with the two methods were 12.94 cm/sec ± 1.1 and 13.59 cm/sec ± 1.1, respectively. There was no significant difference (paired t test) between the methods for mean flow or velocity data. This was true even though flow in the superior sagittal sinus is moderately pulsatile, as shown with the cine PC technique. The ungated PC method provided these data in 13 seconds versus 3.5 minutes for the cine PC method. 相似文献
68.
Marc G Weisskopf Honglei Chen Michael A Schwarzschild Ichiro Kawachi Alberto Ascherio 《Movement disorders》2003,18(6):646-651
Anxiety disorders are common in Parkinson's disease (PD). However, the risk of PD among people with anxiety has not been examined in a prospective cohort study. We examined this relation prospectively within the Health Professionals Follow-Up Study, a cohort of US male health professionals. In 1988, anxiety was assessed using the Crown-Crisp phobic anxiety index in 35,815 men without PD, stroke, or cancer at baseline. There were 189 incident cases of PD during 12 years of follow-up. After adjusting for age, smoking, and caffeine intake, the relative risk of PD among men with the highest level of anxiety (Crown-Crisp index scores of 4 and above) was 1.5 (95% CI = 1.0-2.1; P-trend = 0.01) compared to men with the lowest level of anxiety. This positive association persisted after excluding cases of PD with onset in the first 2 years of follow-up. Use of anxiolytic medication was also associated with an elevated risk of PD (RR= 1.6; 95% CI = 0.9-3.1), but adjusting for this potential confounder did not materially affect the association between anxiety and risk of PD. Our results suggest that anxiety is a risk factor for PD. Whether this association is causal or the result of shared underlying biology remains a question. 相似文献
69.
Elie Mousseaux Iiana Idy-Peretti Jacques Bittoun Odile Jolivet Eric Bourroul Anne Tardivon Pierre Pronneau Jean-Claude Gaux 《Journal of magnetic resonance imaging : JMRI》1994,4(5):719-724
Magnetic resonance imaging maps of velocity were acquired with a 1.5-T system in 10 subjects in a plane perpendicular to the main pulmonary artery. Velocity images were successively acquired with a method developed from Fourier-encoding velocity imaging (FEVI) principles with eight gradient steps and one excitation, and with two-point phase-subtraction mapping. Reconstruction in FEVI was implemented by zero-filling interpolation around the eight gradient steps and then around the four central steps. The methods were compared by using estimates of noise in velocity measurements based on the difference between the experimental map and a smooth fitted map. For the same acquisition time, FEVI with four encoding steps was more precise in velocity measurements than phase mapping. Precision was further increased by the use of eight encoding steps, but acquisition time was doubled. 相似文献
70.
HLA-DR typing by the restriction fragment length polymorphism (RFLP) technique of 42 Greenlanders living in northern Jutland, Denmark, revealed a phenotype frequency of 33.3% for HLA-DRw14b(w6), which is significantly different from the frequency of 0.0% observed among 98 Danes of Caucasian origin. When comparing the two populations, the frequency of other HLA-DRB allogenotypes show insignificant variations. Since HLA-DRw14b(w6) is carried by approximately one-third of the Greenlanders tested, this allogenotype may serve as a useful marker in further anthropological and immunogenetic studies. 相似文献