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941.
R. Grant Steen Suzanne A. Gronemeyer Peter B. Kingsley Wilbum E. Reddick James S. Langston June S. Taylor 《Journal of magnetic resonance imaging : JMRI》1994,4(5):681-691
Precise and accurate inversion-recovery (PAIR) magnetic resonance (MR) measurements of T1 were obtained in eight brain regions and cerebrospinal fluid of 26 healthy volunteers. Accuracy of the technique was assessed by measuring T1 in small fluid volumes with the PAIR technique and with two independent spectroscopic techniques. The mean difference between T1 measured with PAIR and with the two spectroscopic techniques was 3.1% ± 1.3. The precision (reproducibility) of measurements with the PAIR technique was excellent. The coefficient of variation (CV) across 16 measurements in a head phantom was 2.0%, compared with a CV of 2.7% across 45 separate measurements in a single subject. The within-subject CV was 1.8% ± 0.6 in white matter and 1.4% ± 1.0 in basal ganglia. The between-subject CV in 26 healthy volunteers was 3.6% ± 0.6 in white matter and 4.1% ± 1.9 in basal ganglia. Comparison between a patient with an active recurrent brain tumor and an agematched patient with an inactive brain tumor showed that T1 was significantly elevated throughout the brain of the active-tumor patient, especially in white matter tracts, even though no tumor or edema was detected in the white matter on standard MR images. Comparisons between five brain tumor patients and four healthy volunteers of similar age showed that T1 was significantly and substantially elevated throughout the white matter tracts and in the caudate nucleus, putamen, and thalamus. These results are consistent with the hypothesis that white matter tracts are selectively vulnerable to edema and that T1 increases in white matter are a sensitive indicator of patient status or tumor aggressiveness. 相似文献
942.
生长激素在肝硬变门脉高压低蛋白血症手术前的应用研究 总被引:1,自引:1,他引:0
目的:研究生长激素(rhGH)对肝硬变门脉高压低蛋白血症患者手术前的治疗价值。方法:肝硬变门脉高压抑行脾切除、门奇静脉断流手术患者60例,Child分级B级,随机分为rhGH治疗组30例,对照组30例。rhGH组术前5d每天皮下注射rhGH 4IU,对照组给予安慰剂生理盐水。两组术前均行相同肠外营养支持。测定治疗前、治疗后3d、4d、5d血浆白蛋白、球蛋白、前白蛋白及空腹血糖。结果:rhGH组治疗后3d前白蛋白较治疗前及对照组明显升高(P<0.05),治疗后4d、5d仍维持较高水平;治疗后5d白蛋白较治疗前及对照组明显升高(P<0.05)。rhGH组患者一般情况改善,生活质量提高。对照组白蛋白、前白蛋白无明显变化。两组空腹血糖、球蛋白无明显改变。结论:rhGH联合肠外营养支持对纪正肝硬变门脉高压低蛋白血症患者术前低蛋白状态,改善生活质量有良好疗效,由于rhGH起效慢,应早期、足量、足疗程应用。 相似文献
943.
踝关节骨折的AO分型[1] 方法现已被广大学者所接受。B型和C型骨折 ,若早期处理不当 ,则不可避免会导致创伤性关节炎发生。我科自 1996年 7月至 2 0 0 0年 6月 ,共手术治疗踝关节B型、C型骨折4 4例 ,效果满意 ,现报告如下。1 临床资料本组男 31例 ,女 13例 ;年龄 2 4~ 6 3岁 ,平均 36岁 ;右侧 2 8例 ,左侧 16例。 2例为开放性骨折 ,余均为闭合性骨折。致伤原因 :车祸撞跌伤 17例 ,重物压砸伤 6例 ,滑跌伤 2 1例。按Weber Danis分型[1] :B型 2 6例 ,其中伴下胫腓关节分离 12例 ;C型 18例 ,其中伴下胫腓关节分离 17例。2 治疗方法所有病… 相似文献
944.
高浓度吗啡对体外培养的小鼠淋巴细胞增殖的抑制效应北京医科大学药理学教研室陆正武,林志彬利用不同刺激原诱导的淋巴细胞增殖反应,研究吗啡的体外作用机制。结果表明:(1)高浓度吗啡(≥0.1mmol·L-1)以剂量依赖方式,抑制ConA/LPS所致淋巴细胞... 相似文献
945.
946.
Coronary vasomotion in patients with syndrome X: evaluation with positron emission tomography and parametric myocardial perfusion imaging 总被引:1,自引:1,他引:0
Joan G. Meeder Paul K. Blanksma Ernst E. van der Wall Antoon T. M. Willemsen Jan Pruim Rutger L. Anthonio Richard M. de Jong Willem Vaalburg Kong I. Lie 《European journal of nuclear medicine and molecular imaging》1997,24(5):530-537
The aim of this study was to elucidate further the causative mechanism of abnormal coronary vasomotion in patients with syndrome X. In patients with syndrome X, defined as angina pectoris and documented myocardial ischaemia during stress testing with normal findings at coronary angiography, abnormal coronary vasomotion of either the micro- or the macrocirculation has been suggested as the causative mechanism. Accordingly, we evaluated endothelial function, vasodilator reserve, and perfusion heterogeneity in these patients. Twenty-five patients with syndrome X (definitely normal coronary arteriogram, group A), 15 patients with minimal coronary artery disease (group B) and 21 healthy volunteers underwent [13N]ammonia positron emission tomography at rest, during cold pressor stimulation (endothelial function) and during dipyridamole stress testing (vasodilator reserve). Heterogeneity of myocardial perfusion was analysed by parametric polar mapping using a 480-segment model. In both patient groups, resting perfusion was increased compared to the normal subjects: group A, 127±31 ml·min–1·100 g–1; group B, 124±30 ml·min–1·100 g–1 normal subjects, 105±21 ml·min–1·100 g–1 (groups A and B vs normals,P<0.05). These differences were abolished after correction for rate-pressure product. During cold pressor stimulation, the perfusion responses (ratio of cold pressor perfusion to resting perfusion) were similar among the patients and the control subjects (group A, 1.20±0.23; group B, 1.24±0.22; normal subjects, 1.23±0.14). Likewise, during dipyridamole stress testing, perfusion responses were similar among the three groups (group A, 2.71±0.67; group B, 2.77±1.29; normal subjects, 2.91±1.04). In group A the heterogeneity of resting perfusion, expressed as coefficient of variation, was significantly different from the volunteers (20.1±4.5 vs 17.0±3.0,P<0.05). In group B (coefficient of variation 19.4±3.9) the difference from normal volunteers was not significant. In this study, patients with syndrome X and patients with minimal coronary artery disease showed normal perfusion responses during cold pressor stimulation and dipyridamole stress testing. Our findings therefore suggest that endothelial dysfunction and impaired vasodilator reserve are of no major pathophysiological relevance in patients with syndrome X. Rather, other mechanisms such as increased sympathetic tone and focal release of vasoactive substances may play a role in the pathogenesis of syndrome X. 相似文献
947.
High-dose gadoteridol in MR imaging of intracranial neoplasms. 总被引:6,自引:0,他引:6
V M Runge J E Kirsch V J Burke A C Price K L Nelson G S Thomas B L Dean C Lee 《Journal of magnetic resonance imaging : JMRI》1992,2(1):9-18
Twelve patients with a high suspicion of brain metastases by previous clinical or radiologic examinations were studied in a phase III investigation with magnetic resonance (MR) imaging at 1.5 T after a bolus intravenous injection of 0.1 mmol/kg gadoteridol followed at 30 minutes by a second bolus injection of 0.2 mmol/kg gadoteridol. All lesions were best demonstrated (showed greatest enhancement) at the 0.3-mmol/kg (cumulative) dose, with image analysis confirming signal intensity enhancement in the majority of cases after the second gadoteridol injection. More lesions were detected with the 0.3-mmol/kg dose than with the 0.1-mmol/kg dose, and more lesions were detected with the 0.1-mmol/kg dose than on precontrast images. In this limited clinical trial, high-dose gadoteridol injection (0.3-mmol/kg cumulative dose) provided improved lesion detection on MR images specifically in intracranial metastatic disease. 相似文献
948.
Summary: The Internet contains a vast amount of medically relevant information. In order to access this information, however, many networks require one to master applications written in UNIX, an operating system considered by many not to be user friendly. Although these tools may be available on the campus, it is difficult to teach their use unless there is some immediate benefit to the already busy user. From that standpoint, it is important for instructors to realize that common UNIX applications can be utilized as classroom tools to significantly enhance the learning experience by facilitating teacher/student communication. Also, whilst the student enjoys greater communication with the instructor (and with other students) he/she is also becoming adept at using information management tools. 相似文献
949.
950.
T. E. CEDERHOLM A. B. BERG E. K. JOHANSSON K. H. HELLSTRÖM J. E. W. PALMBLAD 《European journal of clinical investigation》1994,24(9):615-620
Abstract Essential fatty acid (FA) deficiency, which may accompany protein-energy malnutrition (PEM), has been associated with impaired inflammatory reactions. We evaluated this relationship by analysing FA profiles and delayed cutaneous hypersensitivity in 20 malnourished elderly non-cancer patients and in 20 age-matched control patients. As indicated by serum cholesterol and serum triglycerides, the lipid levels were decreased by about one-third in the subjects with PEM. In comparison with the controls, there was a reduction in the ω 3 FA (e.g. eicosapentanoate) in total serum lipids (mgl-1 ) and serum phospholipids (%) of 40% and 47%, respectively. Reductions in serum ω 6 FA (e.g. linoleate and arachidonate) levels corresponded to the drop in total FA concentrations (30%). The cutaneous hypersensitivity was impaired in 14 of the malnourished patients. The magnitude of the skin reaction was positively correlated ( P < 0·05) to the concentrations of eicosapentanoate in serum lipids and serum phospholipids, as well as to the linoleate concentration in total serum lipids. Six of the malnourished patients took part in a nutritional intervention programme for 3 months. In parallel with an improvement in the nutritional status there was a 35% increase ( P < 0·05) in the total ω 3 FA serum concentration. Negative skin tests became positive and the median skin induration enlarged threefold ( P < 0·05). Thus, deficiency of ω 3 FA might be one factor contributing to cutaneous anergy in elderly malnourished patients. 相似文献