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61.
1. The relationship between work-rate and the antihypertensive effect of exercise in hypertensives, and the mechanism of that effect, were investigated by a crossover clinical trial. 2. Ten mild hypertensives were randomly divided into two groups. One group performed low work-rate exercise (LWE) on a cycle ergometer for 10 weeks (blood lactate threshold; ~50% of maximum oxygen consumption [V?O2max]). After a 10 week interval without exercise training, these subjects were then switched to a high work-rate exercise (HWE) regimen (4 mmol/ L of blood lactate; ~75% of V?O2max) for another 10 weeks. In the other group, the order of exercise training was reversed. Since two patients withdrew from the protocol during HWE periods, statistical analysis was performed on the data from the remaining eight patients. There were no order effects observed in any of the data from the two groups. 3. During both LWE and HWE, resting blood pressure (BP) fell significantly after the initiation of exercise therapy (P<0.05). Furthermore, the overall effects of 10 weeks of LWE and HWE on BP were not significantly different. 4. The work-rate at the lactate threshold, which reflects physical fitness, had increased significantly by 16 W (P<0.01) after the LWE period and by 11 W (P<0.01) after the HWE. 5. During the LWE period, changes in haemodynamic and humoral variables were not significant, except for a reduction in plasma norepinephrine at week 10 (P<0.05). In the HWE period, changes in haemodynamic and humoral variables were not significant. 6. Based on these findings, LWE is recommended for mild hypertensives because of its safety.  相似文献   
62.
63.
Thirty women, 25 with incontinence and five asymptomatic volunteer control subjects, were evaluated urodynamically by a variety of techniques, including ultrasound cystourethrography. The ultrasound evaluation was found to be a helpful adjunct in diagnosis. In comparison with radiologic techniques it offers more safety, more comfort, more privacy, more viewing time, and less cost. Bladder and urethral morphology during voiding activity and the amount and direction of urethrovesical mobility are easily determined by utilizing ultrasound techniques.  相似文献   
64.
Data on 232 members of a single pedigree, descended from two pairs of original parents, were made available to the participants of Genetic Analysis Workshop 8 (GAW8). In addition to information concerning age and sex, measurements for 10 quantitative traits and genotypes at 22 polymorphic marker loci were also provided for a subset of 193 of these family members. © 1993 Wiley-Liss, Inc.  相似文献   
65.
66.
We reviewed the results of all pediatric patients undergoing intracranial pressure (ICP) monitoring in a 2-year period at our institution. The outcome of patients suffering hypoxia or ischemic injuries (HII) is compared to those suffering non-hypoxic or non-ischemic injuries (NHII). Thirty-four patients had ICP monitors placed during the study period. Inconplete patient information led to the exclusion of 5 patients. An additional 5 patients were excluded because no measures to control ICP were taken after the monitor was placed. Twenty-four patients required treatment for raised ICP (hyperventilation, 24; mannitol, 19; barbiturate coma, 6). Admission Glasgow Coma Score in patients suffering HII (median score 5) and NHII (median score 6) were not significantly different (Mann-Whitney U Test). Only 2 of 8 patients with HII were near-drowning vietims. The remaining 6 had HII from other causes (5 survivors of various forms of asphyxia and 1 of cardiac arrest). All 8 patients had poor outcomes (1 severely disabled; 7 died). The 16 patients with NHII had a variety of diagnoses (6 trauma, 5 encephalitis, 4 bacterial meningitis, 1 diabetic ketoacidosis). Among these, 6 had good outcomes and 10 poor outcomes (2 severely disabled, 2 vegetative, and 6 died). The difference in outcome between patients with NHII and HII is significant at P=0.059 (Fischer Exact test). Patients with NHII may benefit from ICP monitoring. Patients with HII from near-drowning and other causes did not appear to benefit from ICP monitoring and interventions directed at controlling ICP.  相似文献   
67.
目的 为临床研究肝硬化提供有价值的手段。方法 采用99mTc -RBC测定 93例肝硬化患者肝血流 ,选择峰时 (Tmax) ,半廓清时 (T1/2 )、廓清率 (K值 )、肝血流 (LBF)等作为观察指标 ,与正常对照组比较 ;同时用99mTc-MIBI经直肠给药测定其中 5 4例患者门静脉压力 (PVP) ,以心 /肝 (H/L)比值作为分流指数。结果 肝硬化组Tmax、T1/2 、K及LBF分别为 1.2 6± 0 .99(93)min、5 .75± 3.38(93)min、0 .15 4± 0 .116 (93)及 0 .6 10± 0 .2 89(93)L/min ,除Tmax外 ,与对照组均有非常显著性差异 ;Child -A、B、C级各组之间 (除Tmax外 )也均有非常显著性差异或显著性差异 ;Child -A、B、C级各组H/L分别为 0 .49± 0 .18(2 1)、0 .6 9± 0 .16 (15 )、0 .91± 0 .2 1(18) ;PVP分别为 2 .2 2± 0 .5 7(2 1)kPa、2 .85± 0 .38(15 )kPa及 3.5 4± 0 .6 5 (18)kPa。而对照组的H/L及PVP分别为 0 .30± 0 .12 (16 )及 1.6 1± 0 .38(16 )kPa。Child -A、B、C级各组分别与对照组及各组之间比较 ,除Child -B与C级组PVP无显著性差异 (P >0 .0 5 )外 ,其余均有非常显著性差异 (P <0 .0 1)及显著性差异 (P <0 .0 5 )。结论 本法测定肝血流及门脉压力方便 ,无创伤 ,对分析病情 ,判断疗效 ,指导制订治疗方案 ,估计预后等均有较  相似文献   
68.
陈芳  沈炯 《护理研究》2005,19(2):105-107
[目的 ]探讨人工气道气囊压力监测在老年危重病人气管导管护理中的应用价值。 [方法 ]将 60例建立人工气道的老年危重病人随机分成两组 ,实验组应用PORTEX专用气囊压力监测表注气测压 ,对照组采用传统的手指捏感法注气 ;用呼吸机检查漏气情况 ,并比较两组病人的气囊注气容积、气囊压力及并发症发生率。 [结果 ]实验组气囊压力为 2 .45 2kPa±0 .490kPa时 ,气囊容积为 10 .0mL± 4.7mL ,呼吸机检查不漏气 ;对照组气囊压力为 3 .92 3kPa± 0 .73 6kPa时 ,气囊容积为 15 .0mL± 5 .1mL ,呼吸机检查不漏气。两组病人气管黏膜损伤、气囊破裂发生率比较有统计学意义 (P <0 .0 5 ) ;两组病人误吸、食管气管瘘发生率比较无统计学意义 (P >0 .0 5 )。 [结论 ]建立人工气道的老年危重病人气囊压力维持在1.961kPa~ 2 .942kPa ,能有效避免误吸的发生和气管黏膜的损伤。  相似文献   
69.
大鼠脑组织单胺类递质及其代谢产物的检测方法研究   总被引:13,自引:0,他引:13  
目的 :研究大鼠脑组织中单胺类递质及其代谢产物的高效液相反相离子对色谱测定法。方法 :采用LiChrosorbC18,10 μm色谱柱 ,流动相为甲醇 :水 (4 0 :60 ) ,含 0 .0 2 8g LEDTANa2 ,0 .15g LSDS ,0 .2ml LH2 SO4(pH 2 .5~ 3 ) ,荧光检测波长 :λEX=2 85 ,λEM=3 3 3。结果 :对 87只大鼠脑组织中 4种单胺类递质及其代谢产物的含量进行了同时测定 ,高香草酸 (HVA) 2 .5 0~ 40 .0 μg ml、去甲肾上腺素 (NE) 0 .0 1~ 0 .5 0 μg ml、多巴胺 (DA)0 .0 5~ 1.0 0 μg ml、5 羟色胺 (5 HT) 0 .0 2 5~ 0 .5 0 μg ml,峰面积与其含量呈良好的线性关系。 结论 :该法操作简便、快速、准确 ,为组织中单胺类递质及其代谢产物检测的一种理想方法 ,并适用于临床相关研究。  相似文献   
70.
目的:建立一种更符合临床的筋膜间室综合征动物模型,以便于基础及临床研究。方法:用宽度和犬小腿肌腹长度相当的袖带包绕小腿,然后充气使实验肢体全长受压、缺血。12只犬随机分为两组,I组:袖带充气至40kPa,压迫8h;Ⅱ组:袖带充气至80kPa,压迫8h。结果:动态监测组织压并对神经、肌肉行组织学检查,发现实验动物肢体胫前筋膜间室内组织压远远超过4.0kPa,神经、肌肉发生不可逆变性、坏死。结论:用充气袖带压迫法建立的动物模型是成功的,各项指标均达到筋膜间室综合征的诊断标准。  相似文献   
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