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101.
The purpose of this study was to describe the experience of cancer-related fatigue in children of different ages in Taiwan. A total of 17 children with different stages of cancer were interviewed. The methods of data collection included interviews, participants' observations, medical chart reviews and the researcher's reflexive journals. Data were progressively analysed by using qualitative data analysis method throughout the process of data collection. The results indicated that children in all age groups used the word 'tiredness' or 'weary' instead of 'fatigue'. Patients in different age groups described the fatigue differently. Younger children (<9 years) reported that fatigue affected their ability to participate in physical activities. Children aged 10–12 years described fatigue as extreme tiredness that affected their daily lives both physically and psychosocially by altering their daily routine and school attendance and performance. Adolescents described fatigue as unrelievable tiredness that differed from normal tiredness and had a great impact on physical and psychosocial aspect, particularly altering their future life plans and self-performance. This study shows that the definition and impact of fatigue differs among children by age group. Defining and understanding the effects of fatigue can help clinicians assess fatigue and implement effective strategies to alleviate it.  相似文献   
102.
Murine liver-derived inhibitory protein (LIP) capable of inhibiting human lymphocyte proliferation was highly purified from liver extract. Its molecular weight determined by gel filtration and SDS-PAGE was 105,000 and 38,400 respectively. LIP moved electrophoretically at the gamma-globulin region. Its activity in inhibiting lymphocyte proliferation was temperature-stable up to 60 degrees C, and pH-stable between 4 and 11. It was not cytotoxic to lymphocytes as shown in 51Cr-release experiments. The purified LIP possessed arginase activity.  相似文献   
103.
Catheter Ablation. Application of radiofrequency energy to arrhythmogenic substrates after careful cardiac mapping could ensure a high success rate in eliminating certain types of tachyarrhythmias. Future studies of catheter ablation will focus on how to improve ablation efficacy and achieve a better result in various types of tachyarrhythmias. More information about the arrhythmogenic mechanisms will be provided to improve the knowledge of diagnostic and interventional electrophysiology.  相似文献   
104.
目的 研究 5 0Hz工频磁场对细胞内应激活化蛋白激酶 (stress activatedproteinkinase,SAPK/JNK)信号转导途径的影响 ,探索工频磁场生物效应相关的细胞信息转导机制。方法 细胞分别经 0 .4、0 .8mT的工频磁场进行不同时间辐照后 ,利用Western印迹方法 ,比较辐照后细胞与对照细胞胞浆中SAPK及SAPK激酶 (SAPK/ERKkinase 1,SEK1/MKK4 )磷酸化程度。随后以固相激酶分析法(solid phasekinaseassay) ,对经 2个强度分别辐照 15min后的细胞SAPK活力进行测定。结果  0 .4及0 .8mT工频磁场辐照处理可呈时相性增强SAPK磷酸化 ,并且均在 15min时达到最大值 ,SAPK磷酸化分别提高 2 0 %和 17% ;同时SAPK激酶活力也相应增强 ,分别是对照的 (2 .9± 0 .4 )和 (2 .1± 0 .9)倍。然而 ,0 .8mT诱导SAPK磷酸化的时程长于 0 .4mT ,而脱磷酸化的时程短于 0 .4mT。SAPK上游激酶SEK1/MKK4的磷酸化不受工频磁场的影响。结论 工频磁场可以激活SAPK ,但其激活并非通过SEK1/MKK4激酶途径 ;其生物学效应可能与SAPK信息转导途径相关  相似文献   
105.
The diagnostic value of endoscopic biopsy from the ulcer margin (six specimens) and the base (six specimens) in 46 cases of gastric malignancy was evaluated. The biopsy positive rates for malignancy from the ulcer margin and the base were 42 of 46 (91.3%) and 37 of 46 (80.4%), respectively (P = 0.2312). The diagnostic positive rate was increased to 95.6% (44 of 46) when the results of 12 biopsy specimens obtained from the ulcer margin and the base were combined. The diagnostic positive rate was not statistically different when the morphology or the location of the gastric malignancy was considered. No complication of massive bleeding or perforation was found after both sites had been biopsied. It is concluded that the margin and the base of a gastric malignant ulcer are both suitable and diagnostically effective for endoscopic biopsy. If the ulcer margin of the gastric malignancy is difficult to approach, the ulcer base appears to be a satisfactory alternative site for endoscopic biopsy.  相似文献   
106.
Abstract— The effects of adenosine and its analogues on human sperm motility were studied using a transmembrane migration method. Specific binding sites for adenosine in human sperm were also investigated. Adenosine and 5′-N-ethylcarboxamidoadenosine (NECA) stimulated human sperm motility with similar efficacies and the maximal amplitudes of motility increases were both about 70%. 3,7-Dimethyl-1-propargylxanthine (DMPX), a potent A2 antagonist, competitively antagonized NECA-induced motility stimulation. Successively higher concentrations of DMPX shifted the dose-response curve of NECA to the right in a nearly parallel fashion. Dipyridamole, an inhibitor of adenosine uptake, does not reduce the ability of adenosine to stimulate human sperm motility. In radioligand-binding studies, adenosine A1 selective analogues, cyclopentyl-1,3-dipropylxanthine and 1-methyl-2-phenylethyl adenosine, have little competitive effect on [3H]NECA binding in human sperm membrane. These results provide evidence that adenosine enhances human sperm motility via adenosine A2 receptors on the surface of sperm membranes.  相似文献   
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A noninvasive method employing the technique of signal averaging has been developed for recording sinoatrial (S-A) activity (pre-P wave). Recordings were obtained in man at the time of right heart catheterization. A bipolar esophageal electrode was utilized to record the prominent P waves that were used for triggering in the averaging process. After summing 150 beats, which had coefficients of correlation 0.97 or larger, deflections of small amplitude (less than 40 microV) were obtained preceding the atrial activity. Direct catheter recordings were also taken for comparison. With the new noninvasive method, the sinoatrial conduction time (SACT) estimated for patients with sick sinus syndrome (SSS) was 106 +/- 24 ms (101 +/- 20 ms for the same group measured directly). The SACT for healthy subjects used as the control group was 55 +/- 18 ms. There was good correlation between the pre-atrial activity recorded noninvasively by the esophageal electrode method and invasively from the direct catheter method. The linear correlation coefficient between these two techniques was 0.89 (P less than 0.001) in 17 patients.  相似文献   
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