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101.
持续压力超负荷对兔左心室细胞凋亡的影响 总被引:3,自引:1,他引:2
OBJECTIVE: To study the effect of chronic pressure overload on the apoptosis of the left ventricle myocytes in rabbits. METHODS: Rabbit models of chronic pressure overload-induced heart failure were prepared in which dynamic changes of apoptotic myocytes in the left ventricle were observed by way of terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay. RESULTS: Only a few apoptotic cells was observed in the sham-operated group, while in the experimental group, the apoptotic left ventricle myocytes significantly increased after operation, presenting a peak level between day 3 and day 7. Seven days after the operation, the apoptotic myocytes began to decrease and till day 14, the apoptotic cell number had been smaller than that measured on day 1. When signs of heart failure set in, the apoptotic myocytes were again increased (P<0.001). CONCLUSION: During chronic pressure overload, myocyte apoptosis in the left ventricle is elevated at the early stages and undulates subsequently, with the peak occurring before hypertrophy is obvious. 相似文献
102.
目的探讨护理管理路径在应用佩尔地平治疗的重度子痫前期病人的效果,以期达到最佳的治疗效果,并减少并发症的发生。方法将用佩尔地平针治疗的重度子痫前期的病人486例随机分为两组,一组按常规护理,另一组按制定的护理管理路径护理。结果患者依从性对照组为168例,占70%;观察组为228例,占92.68%,P〈0.05,其差异有统计学意义。胎死宫内发生率对照组为9.16%,观察组为0.81%,P〈0.05,其差异有统计学意义。血压的稳定性对照组为36.3%,观察组为97.6%,P〈0.05,其差异有统计学意义。结论护理管理路径可以提高重度妊娠高血压疾病的治疗效果,减少并发症的发生。 相似文献
103.
104.
缺锌对大鼠力竭性游泳前后睾酮和锌水平变化的影响 总被引:5,自引:1,他引:4
本实验动态观察了缺锌和缺锌后补锌对大鼠力竭性游泳前后辜丸和血清睾酮、锌水平以及游泳能力的影响。结果显示:缺锌造成大鼠游泳能力大大降低,补锌后明显增加。不论安静时还是力竭性游泳后12小时内,缺锌大鼠的血清和辜丸锌含量均显著低于对照和补锌大鼠。与对照和补锌大鼠相比,缺锌大鼠的血清和睾丸酮含量,安静时均较低,力竭性游泳后也呈现不同程度的降低。缺锌还造成大鼠辜丸重量的明显下降。结果表明,锌营养不良将损害运动能力。 相似文献
105.
The biomechanical effects of disc injury on flexion-extension were investigated in nine fresh porcine functional spinal units. Under 12 N-m in extension and 6 N-m in flexion, the range of motion among intact specimens were 23.11 degrees -33.29 degrees (mean = 26.07 degrees , SD = 3.25 degrees ), which shifted to 28.04 degrees -38.46 degrees (mean = 31.69 degrees , SD = 3.50 degrees ) when discs were injured. Similarly, the neutral zones among intact and disc injured specimens were 4.88 degrees -12.75 degrees (mean = 9.32 degrees , SD = 2.60 degrees ) and 9.50 degrees -24.43 degrees (mean = 16.80 degrees , SD = 4.69 degrees ) respectively. To obviate the differences between tested specimens, the changes of neutral zone and the range of motion after disc injury were normalized and expressed as ratios as compared to the same items before disc injury. The neutral zone ratio ranged from 1.29 to 3.18 (mean = 1.87, SD = 0.55, p < 0.01). For range of motion, it ranged from 1.13 to 1.42 (mean = 1.22, SD = 0.09, p < 0.01). The change of flexibility coefficient, however, was statistically insignificant in either flexion or extension. The model presented defines the range of motion, the neutral zone as well as the flexibility coefficient under a specific load. It suggests that major spinal instability can be elicited by a minimum flexion-extension moment, as reflected by a profound change of the neutral zone, after disc injury. 相似文献
106.
以正常人外周血淋巴细胞的SCE率作为细胞遗传学指标,研究了Na_2SeO_3与AFB_1相互作用对细胞遗传物质的影响。结果表明,一定浓度的Na_2SeO_3(10 ̄(-5)mol)对AFB_1所诱发的SCE有明显的抑制作用,但当浓度达到10 ̄(-2)mol时,细胞增殖受到抑制,到10 ̄(-1)mol时细胞出现毒性现象。提示Na_2SeO_3具有抑变和细胞毒性双相作用。所以在Na_2SeO_3与AFB_1相互作用的SCE实验中应避免Na_2SeO_3的浓度过高而损伤培养的细胞。 相似文献
107.
There is little information concerning the effects of passive exercise training in healthy humans. This prompted an investigation to evaluate muscle activity and the associated changes in strength and lean body mass resulting from a passive exercise program. Twenty-eight healthy volunteers, aged 26 to 44 years, participated in this six-week study. Lean body mass changes were evaluated by tetrapolar bioelectric impedance measurements, strength changes by isokinetic strength evaluation, and muscle activity by surface EMG techniques. Reproducible muscle activity was recorded in all three muscles studied during two of three preselected exercises. This involuntary muscle activity was attributed to fusimotor and postural reflexes. No significant change (p greater than .05), however, occurred in muscle strength or lean body mass at the end of the six weeks. Lack of these physiologic changes in light of the documented muscle activity is attributed to insufficient training effect. 相似文献
108.
X M Huang 《Health services management research》1994,7(1):2-8
Patient waiting time in outpatient clinics is often the major reason for patients' complaints about their experiences of visiting outpatient clinics. Therefore, patient satisfaction with waiting time plays a crucial role in the process of health quality assurance or quality management. This paper reports the results of a survey on patient attitude towards waiting in an outpatient surgery clinic. Generally patients appear reasonably satisfied if they wait no more than 37 minutes when arriving on time, and no more than 63 minutes when late for appointments. Patients coming up to 15 minutes early are prepared to take full responsibility for the extra waiting caused, but the patients coming even earlier intend to be seen earlier and are only prepared to wait 15 minutes longer than otherwise. The potential applications of patient attitude towards waiting in the quality assurance process, ie setting up waiting time limits and designing patient dispatching rules, are also discussed. 相似文献
109.
应用酶标法测定58例脑梗塞患者和56例健康对照者血清脂蛋白(a)[LP(a)]含量,并同时测定了其他脂代谢指标,对其中26例脑梗塞患者还测定了血浆纤维蛋白溶解(简称纤溶)指标。结果表明脑梗塞组存在显著的脂代谢和纤溶功能紊乱。LP(a)含量增高,与所测脂代谢、纤溶指标无显著相关,是脑梗塞发病独立的危险因素。 相似文献
110.
目的:观察体外循环(CPB)对10例瓣膜置换术病人全血细胞胰岛素受体和红细胞ATP含量的影响。方法:利用放射配体结合试验,测定全血细胞胰岛素受体密度和亲和力;用高效液相色谱法测定红细胞ATP含量,同时监测血糖和胰岛素浓度。结果:转流30分钟,血细胞高亲和胰岛素受体(R1)密度明显增加(P<0.01),亲和力(K1)明显降低(P<0.01),低亲和胰岛素受体(R2)密度也明显增加(P<0.01),但亲和力(K2)变化不大(P>0.05);停机30分钟,上述变化有所恢复,但未到转流前的水平。转流30分钟红细胞ATP含量明显降低(P<0.01),并持续到停机后30分钟,同时伴随血糖明显升高(P<0.01),胰岛素/血糖比值明显降低(P<0.01)。结论:CPB可致血细胞胰岛素受体密度增加而亲和力下降,以及红细胞ATP含量下降。 相似文献