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81.
CROSSOVER COMPARISON BETWEEN THE DEPRESSOR EFFECTS OF LOW AND HIGH WORK-RATE EXERCISE IN MILD HYPERTENSION 总被引:2,自引:0,他引:2
Eiichiro Tashiro Shin-ichiro Miura Manabu Koga Manabu Sasaguri Munehito Ideishi Masaharu Ikeda Hiroaki Tanaka Munehiro Shindo Kikuo Arakawa 《Clinical and experimental pharmacology & physiology》1993,20(11):689-696
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
82.
目的:研究水杨醛-N′-(2-呋喃硫羰基)腙铜配合物(CSFC)在兔体内的药物动力学。方法:10只家兔静脉注射CSFC5mg·kg-1,用反相HPLC法测定血清药物浓度。结果:CSFC的血药浓度-时间曲线符合二室开放模型,主要药动学参数为:T12α=3.4±1.7min,T12β=65.5±14.6min,K12=0.1183±0.0669min-1,K21=0.0228±0.0065min-1,K10=0.1202±0.0407min-1,V0=0.305±0.184L·kg-1,CL=1.896±0.470L·kg-1·h-1,AUC=170.1±57.0mg·min-1·L-1。结论:CSFC在兔体内分布迅速而广泛,消除也较快。家兔静注5mg·kg-1,可维持抗结核杆菌有效血浓度6h。 相似文献
83.
84.
Carlo Bertucci Enrico Domenici Piero Salvadori 《Journal of pharmaceutical and biomedical analysis》1990,8(8-12):843-846
The application of a circular dichroism (c.d.) detection system in HPLC using a chiral stationary phase is presented. The simultaneous measurement of the absorbance and c.d. signal allows the evaluation of the anisotropy factor (g = Δ/) and thus the determination of the enantiomeric excess (e.e.) of the eluates. When this detection system is used in preparative chiral chromatography the collection of the enantiomeric fractions can be readily optimized. 相似文献
85.
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
86.
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
87.
The present study examined the influences of dopamine (DA) receptor stimulation on enkephalin (Met5-enkephalin; ME) and tachykinin (substance P; SP) systems of basal ganglia of Sprague-Dawley rats, lesioned as neonates with 6-hydroxydopamine (6-OHDA). It has been proposed that the neonatal 6-OHDA-lesioned rat could serve as a model for the DA deficiency and self-injurious behavior (SIB) observed in the childhood neurological disorder. Lesch-Nyhan syndrome. In agreement with earlier work, the present study found that the neonatal 6-OHDA treatment at 3 days of age, reduced DA and caused an increase in ME and a decrease in SP content in the striatum and substantia nigra, when tested as adults. Administration of the DA precursor, L-dihydroxyphenylalanine (L-DOPA), to lesioned animals, induced SIB; increased DA and DOPAC levels; produced a greater decrease (-64%) in SP levels in the striatum and substantia nigra than was observed with lesion alone (-28%). The L-DOPA-induced decrease in SP levels and the SIB observed in the lesioned animals were blocked by pretreatment with the D1 receptor antagonist, SCH-23390. Moreover, administration of the D1 receptor agonist, SKF-38393, but not the D2 agonist, LY-171555, to lesioned animals mimicked the L-DOPA responses in all respects, except that the agonists did not alter DA or DOPAC levels. None of the DA agonists or antagonists treatments affected lesion-induced increase in ME levels in the striatum. These results indicate for the first time, that SIB precipitated by DA agonists in neonatal dopaminergic denervated animals, is associated with a marked and selective decrease in SP in the striatonigral SP neurons. This process has two components: (a) a retarded development of the SP system due to neonatal dopaminergic denervation: and (b) a depletion of the remaining SP, presumably by enhanced release due to D1 DA receptor-mediated activation of striatonigral SP neurons. 相似文献
88.
89.
Peter D. Le Roux David S. Jardine Paul M. Kanev John D. Loeser 《Child's nervous system》1991,7(1):34-39
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
90.
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