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61.
Summary Maximal oxygen uptake was assessed in 101 randomly selected 8 and 13 year old children. In both age groups a significantly higher aerobic capacity was found in boys than in girls, both in absolute terms and when maximal oxygen uptake was related to body weight, lean body mass and lean leg volume. Among girls, maximal oxygen uptake per kg body weight was lower in the older than in the younger (p<0.05). Estimation of spontaneous physical activity, by means of a questionnaire and the actometry method, indicated that physical activity was greater in children with a high than in those with a low aerobic capacity. 相似文献
62.
B. Sorbe 《International journal of gynecological cancer》2004,14(5):788-793
In a large study on 1,220 patients with ovarian carcinoma in FIGO stages I-IV, the prognostic importance of the time factor for start of postoperative chemotherapy was studied together with other important factors for long-term survival. The patient series was a total geographic material of ovarian carcinoma patients treated during the years 1975-1993. All patients were followed up for 10 years or until death. The 5-year cancer-specific survival rate of the complete series was 50%. Significant and independent prognostic factors with regard to long-term cancer-specific survival were FIGO stage, histology, tumor grade, and completeness of the primary surgery. Special attention was paid to the prognostic importance of the time interval between primary surgery and the first course of chemotherapy. Patient groups with intervals shorter or longer than the median value were compared. In early-stage disease, no significant difference was noted. In advanced and bulky disease, an interval longer than the median value seemed to be beneficial compared with a shorter interval. However, after correction for other prognostic factors, the interval was not a significant factor (P = 0.647) with regard to the cancer-specific survival rate. Therefore, the time factor should not be an important argument for how to best organize the gynecologic oncology service. 相似文献
63.
目的:探讨运用DSA设备作吞咽功能检查的价值。材料和方法:用DSA设备对正常组24例,咽异感症患者32例,做上至颅底、下达第七颈椎平面的正侧位动态采集,了解吞咽状况,并行咽传输时间测定,进行对照研究。结果:正常对照组咽传输时间为1.441±0.302s,咽异感症患者咽传输时间为1.367±0.409s,两组结果相比统计学上无显著差异,但后者较易发生咽部钡剂滞留等改变。结论:DSA机由于采集速度快,不但在心血管检查及介入治疗方面有重要意义,而且在非血管性脏器的动力学检查中也起着一定的作用。由于能完整记录钡剂通过咽部的全过程,故此方法是吞咽功能检查的良好方法之一。 相似文献
64.
Sylvain Miraux Jean-Michel Franconi Eric Thiaudière 《Magnetic resonance in medicine》2006,56(3):469-473
Blood velocity is a functional parameter that is not easily assessed noninvasively, especially in small animals. A new noninvasive method that uses magnetic resonance angiography (MRA) to measure blood flows is proposed. This method is based on the time-of-flight (TOF) phenomenon. By initially suppressing the signal from the stationary spins in the area of interest, it is possible to sequentially visualize only the signal from the moving spins entering a given volume. With this method, 3D cine images of the blood flow can be generated by positive contrast, with unparalleled spatial (<200 microm) and temporal resolutions (<10 ms/image). As a result, it is possible to measure flow in sinuous paths. The present method was applied in vivo to measure the blood velocity in mouse carotid arteries. Because of its robustness and simplicity of implementation, this method has numerous potential applications for fundamental studies in small animal models. 相似文献
65.
Objective: The aim of this study was to establish reproducible two-dimensional electrophoretic assay used for profiling and identification of differentially expressed proteins in human stage I lung adenocarcinoma and paired normal tumor-adjacent tissue. Methods: The proteins from 12 human stage I lung adenocarcinoma tissues and normal tumor-adjacent tissues were separated using isoelectric focusing electrophoresis (the first dimension) and the subsequent homogeneous SDS-polyacrylamide gel electrophoresis (SDS-PAGE) (the second dimension). The differentially expressed proteins were determined with PDQuest image analysis software, and identified using matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS) and database searching. Results: The well-reproducible 2-DE gel patterns of human stage I lung adenocarcinoma and normal tumor-adjacent tissues were profiled and 26 differentially expressed proteins uncovered. Nine of these 26 protein spots were cut out from the preparation gels and determined with MALDI-TOF-MS. Searching against the protein database, four candidate proteins were identified. They were 60S acidic ribosomal protein P2, Cathepsin B1, Apolipoprotein A-I precursor, and La 4.1 protein. Conclusion: In this study, high reproducible 2-DE gel protein images of human stage I lung adenocarcinoma and paired normal tumor-adjacent tissues were achieved successfully, and 4 differentially expressed proteins were revealed. These data will be helpful for screen of early biomarker and study of molecular mechanisms of human lung adenocarcinoma. 相似文献
66.
目的研究羟基红花黄色素A(HSYA)的胃肠吸收转运机制。方法采用Caco-2细胞模型考察孵育时间、介质pH、药物浓度及抑制剂(环孢菌素A和叠氮钠)对羟基红花黄色素A摄取转运的影响,并分析HSYA灌胃给药后在大鼠尿及粪中的累积排泄。结果HSYA的摄取符合被动扩散过程,pH7.8环境下药物的细胞摄取量[(1.05±0.045)mg·g-1]低于pH5.4[(1.24±0.09)mg·g-1](P<0.05),其在Caco-2单细胞层的表观透过系数(Papp)为(2.16±1.21)×10-8cm·s-1,加入环孢菌素A和叠氮钠后其Papp显著提高(P<0.05),分别为(47.92±17.8)×10-8和(12.53±4.55)×10-8cm·s-1。HSYA大鼠灌胃给药(5.6mg·kg-1)后31h,其尿和粪中的累积排泄量分别为给药剂量的0.74%和28.57%。结论HSYA的吸收基本符合被动扩散过程并有P-gp的参与,其黏膜透过性较差,碱性环境相对不利于药物的吸收。HSYA口服后的胃肠吸收较差,大量的药物被排出体外或在胃肠道内被代谢转化。 相似文献
67.
68.
Thomas Höge 《Stress and health》2009,25(1):41-51
Against the theoretical background of the effort–recovery model and the action regulation theory, the author presents a cross‐sectional questionnaire study testing hypotheses about the relationship between work‐related time pressure, cognitive and emotional irritation, work–family conflict and psychosomatic complaints. Subjects were 576 female home care nurses. Results of a path analysis show that the relation of time pressure and psychosomatic complaints is partially mediated by experiencing a work–family conflict; also the relation of time pressure and work–family conflict is partially mediated by cognitive and emotional irritation. It is argued that cognitive and emotional irritation are fruitful concepts for a more comprehensive understanding of the relationship between work stressors and the development of strain‐based work–family conflict. Implications for the prevention of work–family conflict are outlined. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
69.
英语阅读障碍儿童词汇命名加工特征的研究 总被引:1,自引:1,他引:0
目的研究英语阅读障碍儿童操作英语词汇的相关能力 ,探索英语阅读障碍的表现特点与矫治的手段。方法英语真、假词命名实验 ,观察 3 4名阅读障碍儿童和 3 4名对照组儿童的实验结果。结果 ( 1)障碍组右视野在真、假词的命名时间上与对照组存在显著差异 ;( 2 )障碍组在真词和假词上的命名错误率均大于正常组 ,假词命名的错误率大幅增加。 ( 3 )障碍组右视野的真词命名时间明显长于左视野 ,假词命名的错误率也明显大于左视野。结论英语阅读障碍的儿童显示出了操作英语语音能力的欠缺以及左测大脑半球活动水平不足的倾向。 相似文献
70.
在时域循环卷积运算实现反卷积方法的基础上,基于广义逆的概念提出了一种改进算法,该算法不仅可以有效地避开无谱逆问题,而且运算量增加较少,易于编程实现。 相似文献