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91.
胎儿声振动刺激反应的研究 总被引:5,自引:0,他引:5
目的:了解不同孕龄胎儿对声振动刺激的反应。方法:对435例次正常中、晚期妊娠妇女进行声振胎心试验(VAS-T)、声振胎动试验(SPFM),并对声振动刺激前、后胎心率变化规律进行前瞻性研究。结果:(1)从24周开始,胎儿对声振刺激有反应,但大部分未能达到VAS-T诊断标准,而胎动反应良好。(2)妊娠28周开始,声振刺激后,90%以上的胎儿出现显著的胎动、胎心率加速反应,足月胎儿反应率在98%以上。(3)SPFM阳性率的显著提高早于VAS-T。提示:28周后胎儿神经系统发育已趋完善。胎儿运动神经的发育成熟早于植物神经。 相似文献
92.
陈爱华 《南方医科大学学报》1990,(3)
本文用X线电影摄影方法评价了49例左室舒张(充盈)功能的影响因素。冠心病(CAD)组23例,高血压病组12例,正常对照组14例。左室充盈功能或顺应性主要受冠脉病变严重程度的影响。冠脉狭窄程度越重,并有陈旧性心肌梗塞、室壁运动异常、EF下降,则充盈功能受损愈明显。血压、年龄因素对舒张充盈功能的影响较小。在CAD组中,心率与1/3充盈分数呈负相关,与正常化高峰充盈率(NPFR)不相关,而EF则与NPFR相关良好。 相似文献
93.
94.
三七粉末透皮吸收研究 总被引:9,自引:0,他引:9
目的 :研究三七粉末的透皮吸收性及选择最佳促透剂。方法 :设计体外离体透皮试验法 (即用离体鼠皮在单室扩散池中进行试验 ) ,测定不同时间三七粉末中有关成分的透皮总量 (以三七皂苷为对照 ) ,计算透皮吸收率及促透剂的促透倍数。结果 :三七粉末的丙二醇溶液有一定透皮吸收能力 ,不同浓度的氮酮 (Azone)对其具有显著的促透作用 ,但Azone的促透效果与其剂量不呈直线关系 ,5 %Azone效果好于 7%Azone。结论 :本方法简便、易于操作、重现性较好 ,可用于制剂工艺研究中促透剂的选择 相似文献
95.
G. Dewasmes B. Bothorel A. Hoeft V. Candas 《European journal of applied physiology》1993,66(6):542-546
Summary Thermoregulatory sweating [total body (m
sw,b), chest (m
sw,c) and thigh (m
sw,t) sweating], body temperatures [oesophageal (T
oes) and mean skin temperature (T
sk)] and heart rate were investigated in five sleep-deprived subjects (kept awake for 27 h) while exercising on a cycle (45 min at approximately 50% maximal oxygen consumption) in moderate heat (T
air andT
wall at 35° C. Them
sw,c andm
sw,t were measured under local thermal clamp (T
sk,1), set at 35.5° C. After sleep deprivation, neither the levels of body temperatures (T
oes,T
sk) nor the levels ofm
sw, b,m
sw, c orm
sw, t differed from control at rest or during exercise steady state. During the transient phase of exercise (whenT
sk andT
sk,1 were unvarying), them
sw, c andm
sw, t changes were positively correlated with those ofT
oes. The slopes of them
sw, c versusT
oes, orm
sw, t versusT
oes relationships remained unchanged between control and sleep-loss experiments. Thus the slopes of the local sweating versusT
oes, relationships (m
sw, c andm
sw, t sweating data pooled which reached 1.05 (SEM 0.14) mg·cm–2·min–1°C–1 and 1.14 (SEM 0.18) mg·cm–2·min–1·°C–1 before and after sleep deprivation) respectively did not differ. However, in our experiment, sleep deprivation significantly increased theT
oes threshold for the onset of bothm
sw, c andm
sw, t (+0.3° C,P<0.001). From our investigations it would seem that the delayed core temperature for sweating onset in sleep-deprived humans, while exercising moderately in the heat, is likely to have been due to alterations occurring at the central level. 相似文献
96.
Bo-Lennart Johansson Ulla Berg Ulla Freyschuss Kerstin Hall Staffan Troell 《Pediatric nephrology (Berlin, Germany)》1990,4(6):589-592
The influence of metabolic control (HbA1c), noradrenaline (NA) and insulin-like growth factors (IGF-I and IGF-II) on renal function and size was investigated in 11 insulin-dependent diabetes mellitus patients aged 11–17 years. Renal function was evaluated in terms of glomerular filtration rate (GFR) and effective renal plasma flow (ERPF). Renal size was determined as renal parenchymal volume (RPV) by ultrasonography. The patients' HbA1c values ranged from 8.2% to 12.9% (normal range 5.5–8.5%) and their GFR and ERPF were higher than normal. Their IGF-II values were higher, and NA and IGF-I levels were lower than those of healthy controls. Inverse correlations between NA and GFR (r=–0.66) and NA and ERPF (r=–0.63) were found. No correlation was found between serum IGF-I and renal functional parameters. The IGF-II values correlated with GFR and HbA1c (r=0.63,r=0.70 respectively). There were linear correlations between RPV and GFR, RPV and ERPF, HbA1c and GFR, and ERPF and RPV. Decreased NA concentrations and increased IGF-II values appear to be factors contributing to renal hyperfunction in these patients. 相似文献
97.
THE INFLUENCE OF CAPTOPRIL AND NALOXONE ON THE VALSALVA MANOEUVRE AND SYSTOLIC TIME INTERVALS IN HEALTHY VOLUNTEERS 总被引:1,自引:0,他引:1
J. P. Richter De K. Sommers J. R. Snyman 《Clinical and experimental pharmacology & physiology》1994,21(4):301-305
1. The aim of the study was to ascertain whether the inhibition of the sympathetic nervous system by angiotensin-converting enzyme (ACE) inhibitors is mediated by endogenous opioids. Naloxone was used to evaluate the effects of the latter on systolic time intervals (STI) and Valsalva manoeuvre-induced blood pressure and heart rate changes. 2. Baseline recordings were done in 12 healthy male volunteers and repeated 2h after oral administration of 75 mg of captopril and again after naloxone 0.4 mg/kg was administered intravenously over 10 min. 3. After captopril there was a significant reduction in systolic (P<0.02) and mean blood pressure (P<0.04) without any changes in heart rate. Furthermore, captopril increased the Valsalva ratio (P<0.06) but did not influence inotropism as indicated by STI. Naloxone did not influence any of these findings. 4. The changes in the Valsalva ratio after captopril were mediated by an increase in the maximum bradycardia in nine of the 12 subjects. 5. The results indicate that endogenous opioids do not play a role in the putative sympatholytic effect of ACE inhibition. 相似文献
98.
Twenty-four patients treated with 150 mg amitriptyline per day for an episode of major depression underwent a standardized heart rate analysis (HRA) before therapy and after 14 days. The battery of cardiovascular reflex tests included the determination of the coefficient of variation (CV) while resting and during deep respiration, a spectral analysis of heart rate, the heart rate response to standing, and the Valsalva manoeuvre. The results of the initial HRA did not differ from a group of 24 normal control subjects matched for age and sex. On day 14 of treatment the patients showed significantly reduced values of heart rate variability in all tests (P<0.0001), probably due to the anticholinergic side effects of amitriptyline. Heart rate increased form 78.1 to 93.6 bpm on average (P<0.0001). Abnormal CV at rest was registered in 96% of the patients; during deep respiration 29% showed abnormal CV results. An abnormal spectral analysis was found in 100% of the cases (low frequency peak: 42%, mid-frequency peak: 100%, high frequency peak: 79%). The heart rate response to standing was abnormal in 75% and the Valsalva test in 33% of the cases. Eighty-eight percent of the patients fulfilled the criteria of a cardiovascular autonomic neuropathy under the conditions of amitriptyline therapy. As yet, the consequences of these changes for the patients have not been sufficiently elucidated. 相似文献
99.
咖啡因主要经肝细胞色素P450IA2代谢,测定其药代动国学参数可反映该P450亚型的活性。本研究显示咖啡因清除相为一级动力学;唾液和血浆的药代动力学参数有良好的相关性;含体重因素的清除率的变异系数比半减期小;用一次采样测定其清除率以8h时点为宜。 相似文献
100.
苯作业工人白细胞降低者的总估校正现患率 总被引:7,自引:0,他引:7
选择乡镇工业苯作业工人4次外周血白细胞计数中的间隔半年的两次数据,应用俘获再俘获法,计算其白细胞降低者的总估校正现患率(ACPR)。结果苯接触组为36.8l%(29.14%~44.48%),对照组为12.71%(7.20%~18.22%)具有显著差异,其相对危险度为2,9。用常规法求得的4次检出率分别是:苯接触组为26.37%,18.73%,27.93%,36.76%;对照组为6。85%,7.38%,7.94%,15.00%。均在其ACPR之95%可信限内,可见ACPR计算方法简便、结果准确,值得推广。对于稳定的人群,可用其每年一次的健康监护资料计算ACPR。 相似文献