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排序方式: 共有430条查询结果,搜索用时 15 毫秒
91.
92.
Papillary endolymphatic sac tumors: CT, MR imaging, and angiographic findings in 20 patients 总被引:6,自引:0,他引:6
93.
To quantitatively map and compare patterns of regional cardiac metabolism with greater spatial resolution than is possible with positron emission tomography (PET), the authors developed autoradiographic techniques for use with combinations of radiolabeled fluorodeoxyglucose (FDG), glucose (GLU), and acetate (ACE) and applied the techniques to normal rats. Kinetic models were developed to compare GLU-based oxidative glucose metabolism with FDG-based total glucose metabolism (oxidative plus anaerobic) and to compare ACE-based overall oxidative metabolism with FDG-based total glucose metabolism. GLU-based metabolism generally paralleled FDG-based metabolism, but divergence occurred in certain structures such as the papillary muscles, where FDG-based metabolism was much greater. ACE-based metabolism also generally paralleled FDG-based metabolism, but again, the papillary muscles had relatively greater FDG-based metabolism. These discrepancies between FDG-based metabolism and GLU- or ACE-based metabolism suggest the presence of high levels of anaerobic glycolysis. Thus, the study indicates that anaerobic glycolysis, in addition to occurring in ischemic or "stunned" myocardium (as has been shown in recent PET studies), occurs normally in specific cardiac regions, despite the presence of abundant oxygen. 相似文献
94.
Robert F. Nease Scott M. Whitcup Leon B. Ellwein Gregory Fox Benjamin Littenberg 《Ophthalmic epidemiology》2013,20(3):169-185
PURPOSE. To quantify and compare the reduction in quality of life due to visual impairment and angina using patient preferences (utilities). METHODS. Using a standard time tradeoff method, we obtained utilities for current vision, monocular and binocular blindness, current angina, and moderate angina in 60 patients with both vision problems and angina pectoris who sought care at the National Eye Institute (NEI), National Naval Medical Center, or Barnes-Jewish Hospital. Patients were characterized clinically based on visual acuity and the Duke Activity Status Index (DASI). Patients also completed a seven-item version of the NEI Visual Functioning Questionnaire and the SF-36 Health Survey Questionnaire. RESULTS. Patients had a median visual acuity of 20/100 in the worst eye, 20/40 in the better eye, and a median DASI of 24.2 (0 = severe functional limitations due to anginal symptoms, 58.2 = no limitations). There was substantial variation in utilities among patients. The average utility for current vision (relative to ideal vision [= 1.0] and death [= 0.0]) was 0.82; the average utility for current angina (relative to no angina symptoms [= 1.0] and death [ = 0.0]) was 0.89. Among 26 patients with both visual impairment and recent anginal symptoms, the decrement in utility (on a scale ranging from ideal health [= 1.0] to death [= 0.0]) imposed by current visual impairment was greater than that imposed by current angina symptoms (0.146 versus 0.072, p=0.08, Wilcoxon signed rank test). The decrement in utility associated with binocular blindness was greater than the decrement associated with the symptoms of moderate angina (0.477 versus 0.039, p < 0.0001). CONCLUSIONS. Clinical status is not a surrogate for patient preferences regarding vision impairment or angina. There is substantial variation in utilities within the study population for both experienced and theoretical impairment states which is not explained by variations in clinical status. Some states of visual impairment may pose a greater quality of life burden than anginal symptoms. Because patient preferences for vision vary greatly, individual assessment is warranted for consideration in therapeutic decision making. 相似文献
95.
A total of 125 patients with severe peripheral vascular disease were examined with translumbar aortography. The mean dose of contrast medium injected was 65 ml of Angio Conray (containing 31.2 g of iodine). Forty patients were pretreated with mannitol, and 32 received furosemide. Thirty-eight patients (30%) had diabetes and, presumably, diabetic nephropathy. Eleven of them had significant azotemia (creatinine values greater than or equal to 4 mg/dl). Administration of contrast material did not significantly reduce renal function in any patient group. We conclude that acute renal failure following the injection of contrast material is uncommon, is reversible, and almost always occurs when avoidable complicating factors are present. 相似文献
96.
97.
胰岛素样生长因子-1(IGF-1)和胰岛素可能是肠道生长的重要调节因子。为了研究肠细胞萎缩和再生期间小肠IGF-1受体(IGF-IR)和胰岛素受体(IR),我们比较了禁食72小时和肠内再喂养24~72小时大鼠空肠IGF-IR和IR表达的指标。禁食引起肠萎缩,血浆胰岛素和IGF-1浓度降低以及空肠IGF-1信使RNA(mRNA)水平的明显降低,再喂养可逆转这些改变。禁食明显增加胰岛素与空肠特异性地结合,IR含量(达对照组的230%)和9.6kb和7.4kbIRmRNA转录本水平(分别达对照组的202%和218%)。再喂养时,这些IR指标迅速降到对照组水平。禁食时IGP-IR(用Scatchard分析)和IGF-1-RmRNA无明显的改变。再喂养后的前24小时间11-kbIGF-IRmRNA转录本明显增加(达对照组水平166%),IGF-IR数量增加3倍。我们的结论是:大鼠空肠的IR和IGF-IR受到不同营养物利用状态的调节。再喂养时空肠IGF-1和IGF-IR表达的向上调节表明,IGF作用途径在对肠内营养物产生肠道营养反应的过程中起作用。 相似文献
98.
99.
维拉帕米对大鼠肝脏贮脂细胞增殖及胶原基因表达的影响 总被引:2,自引:0,他引:2
在肝纤维化的发生发展过程中,细胞外基质的过度合成和异常沉积是最主要的病理过程。研究表明,病理状态下,贮脂细胞(FSC)被激活,数量增多,分泌大量的胶原等细胞外基质,导致肝纤维化的发生、发展[1]。材料和方法一、实验动物雄性SD大鼠10只,其中5只皮下注射40%CCl4茶油溶液建立肝纤维化模型。二、试剂链霉蛋白酶和Nycodenz购于Sigma公司;胶原酶购于上海医工院;维拉帕米(Ver)购于Knoll公司;RNA提取剂、P32dCTP、随机引物标记试剂盒购于Gibco、亚辉、Promega公司三… 相似文献
100.
新生牛跟腱胶原蛋白海绵与细胞的生物相容性 总被引:1,自引:1,他引:1
目的:采用新生牛跟腱制备生物医用胶原蛋白海绵,通过分别接种Vero细胞、天祝白牦牛胚胎皮肤原代细胞和岷县黑紫羔羊睾丸原代细胞至胶原蛋白海绵组织支架上,观察新生牛跟腱胶原蛋白海绵与3种细胞的生物相容性。方法:实验于2006-02/05在西北民族大学生命科学与工程学院生物工程与技术国家民委重点实验室完成。①用新生牛跟腱经冰醋酸、胃蛋白酶等消化,经盐析、透析及冻干等处理后,制备成胶原蛋白海绵。②在六孔板中,将Vero细胞、天祝白牦牛胚胎皮肤原代细胞和岷县黑紫羔羊睾丸原代细胞分别接种于经紫外线、臭氧灭菌后的胶原蛋白海绵上,经37℃体积分数为0.05的CO2恒温培养;并用另一组细胞在凯氏瓶中培养作对照实验。用奥林帕斯倒置相差显微镜及JVC摄像系统观察、拍摄与记录细胞生长情况,并于培养11d,用考马斯亮蓝和苏木精-伊红染色,证实相差显微镜观察的结果。结果:①胶原蛋白海绵制备结果:用新生牛跟腱制备得到具有一定孔隙度的胶原蛋白海绵,经紫外线、臭氧灭菌后可进行细胞培养。②3种细胞在胶原蛋白海绵上和六孔板底的生长情况:3种细胞接种后5h,在胶原蛋白海绵周围的六孔板孔底可看到Vero细胞已贴壁、伸展,个别细胞有分裂现象,在胶原蛋白海绵表面,隐约可见圆形细胞排列。Vero细胞和天祝白牦牛胚胎皮肤原代f2细胞接种72h、岷县黑裘皮羔羊睾丸原代f2细胞接种48h时,孔底细胞已经铺满单层,但与对照孔比较,生长速度较慢。②3种细胞用考马斯亮蓝细胞骨架染色和苏木精-伊红染色的结果:培养到第11天,3种来自不同动物、不同组织的细胞接种的胶原蛋白海绵支架孔中均有大量细胞良好生长,胶原海绵外观变得挺拔、透明、有韧性。结论:新生牛跟腱胶原蛋白海绵,对Vero细胞、天祝白牦牛胚胎皮肤原代细胞和岷县黑紫羔羊睾丸原代细胞无毒性,3种细胞均能在其上良好生长,但在体内是否会引起免疫排斥反应,还有待进一步研究。新生牛跟腱有望成为医用胶原蛋白海绵产品新的原材料。 相似文献