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61.
用放射免疫法测定产后40天和60天乳母血清泌乳素基础水平和吸吮后泌乳素最大反应性增值,发现其与乳母泌乳量、婴儿吸吮频率、吸吮时间之间均不存在正相关关系,推测引起泌乳素分泌除吸吮外,还存在其他机理。  相似文献   
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63.
在1000人中统计白鼻毛发生率为36.4%,白发为26.1%,白须为7.5%,白眉为3.3%,白睫为1.6%。我们认为白鼻毛比白发等作为衰老的一项指标更有其代表性。白鼻毛发生率:男性(53.4%)高于女性(13.4%),知识分子(60.8%)高于工人(26.3%)及农民(26.4%),日本人高于中国人,差异显著。  相似文献   
64.
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   
65.
66.
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   
67.
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   
68.
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   
69.
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   
70.
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   
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