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21.
Toe temperature versus transcutaneous oxygen tension monitoring during acute circulatory failure 总被引:1,自引:0,他引:1
Measurements of toe temperature and transcutaneous PO2 (PtcO2) have been both suggested for non-invasive assessment of peripheral blood flow in acute circulatory failure. The underlying
principle of the two methods is that cutaneous vasoconstriction occurs early when tissue perfusion is altered. In 15 patients,
we compared the two measurements during cardiogenic shock (27 measurements) or septic shock (29 measurements). Toe-ambiant
temperature gradient and PtcO2 correlated well together (r=0.66, p(0.001) especially in hyperkinetic septic shock (r=0.79, p(0.001). In cardiogenic shock, toe-ambiant temperature correlated well with cardiac index (r=0.63), stroke index (r=0.64) and oxygen transport (r=0.65), and these correlations were stronger than for PtcO2. In septic shock, both techniques were poor indicators of blood flow indexes but PtcO2 rather correlated with arterial pressure (r=0.66) and left ventricular work (r=0.66). Trend evaluation of data revealed in cardiogenic shock that the increase in toe temperature usually preceded the increase
in PtcO2. Since measurement of PtcO2 is technically more complicated, correlates less well with standard hemodynamic parameters and later reflects cardiovascular
improvement, it has no advantage over measurement of toe temperature in circulatory shock. In cardiogenic shock, measurements
of toe temperature can reliably track cardiac output changes. In septic states, however, non-invasive assessment of skin perfusion
is of limited interest. 相似文献
22.
A. Lecci F. Borsini L. Gragnani G. Volterra A. Meli 《Journal of neural transmission (Vienna, Austria : 1996)》1991,83(1-2):67-76
Summary Stress-induced hyperthermia (SIH), which is seen in the last mice removed from the cage, is a novel animal model sensitive to anxiolytic drugs. SIH is antagonized by CL 218872 (25 and 50 mg/kg, os), by tracazolate (5 and 7.5 mg/kg, ip) and by 2-AP-5 (50 and 100 mg/kg, ip). At higher dose, CL 218872 (100 mg/kg, os) and tracazolate (12.5 mg/kg, ip) lose their activity.PK 9084 (5–40 mg/kg, ip) and CGS 9896 (2–20 mg/kg, both ip and os) were also ineffective in preventing SIH. The anti-hyperthermic effect of CL 218872 (25 mg/kg) and tracazolate (7.5 mg/kg) was blocked by the benzodiazepine antagonist Ro 15–1788 (15 mg/kg). CGS 9896 (10 mg/kg, os) also reversed the effect of CL 218872 (25 mg/kg) on SIH.Differently from anxiolytics, MK-801 (0.5–1 mg/kg, os), PCP (2.5 mg/kg, ip) and d-amphetamine (10 mg/kg, ip) evoked hyperthermia in the first set of mice and prevented a further stress-induced rise of body temperature in the last set of mice. 相似文献
23.
H. S. Lee H. Y. Meltzer M.D. 《Journal of neural transmission (Vienna, Austria : 1996)》1991,86(1):71-76
Summary Buspirone, a putative serotonin (5-HT)1A partial agonist, did not produce hypothermia in 17 normal volunteers in a placebo controlled, single blind study. Thus, buspirone may be a weaker agonist at those 5-HT1A receptors which mediate hypothermia compared to ipsapirone or gepirone, two other 5-HT1A partial agonists which have been reported to produce hypothermia by a 5-HT1A-mediated mechanism. 相似文献
24.
Using data from the National Health and Nutrition Examination Survey (NHANES II) 1976-1980, we demonstrate how cross-sectional total serum cholesterol surveillance data can be used by an individual to assess current and future personal cholesterol risk status. We propose statistical models, based on a person's current measured cholesterol level and the relationship between cross-sectional age and cholesterol percentile estimates, that will allow prediction of future cholesterol levels or the age at which specified cholesterol risk levels will be reached if no cholesterol-altering intervention is taken. These models incorporate the observed variation in the NHANES II data and expected intraperson biological variation and intralaboratory analytical variation. We illustrate the adequacy of the models using data from the longitudinal Framingham Study. 相似文献
25.
Oral self-administration and operant tasks have been used successfully to confirm ethanol′s positive reinforcing effects
in rats. However, in flavor conditioning tasks, ethanol is typically found to have aversive effects. The present studies explored
this apparent paradox by examining the change in value of a flavor paired with orally self-administered ethanol in two different
limited-access procedures. Rats were food-deprived and trained to drink (experiment 1) or to barpress for (experiment 2) 10%
(v/v) ethanol during daily 30-min sessions using prandial initiation techniques. All rats were then exposed to a differential
flavor conditioning procedure in which banana or almond extract was added to the drinking solution. One flavor (counterbalanced)
was always mixed with ethanol (CS+), whereas the other flavor was mixed with water (CS–). By the end of conditioning, rats
in both experiments drank more flavored ethanol than flavored water, confirming ethanol’s efficacy as a reinforcer. Moreover,
barpress rates for CS+ exceeded those for CS– in the operant task. Ethanol doses self-administered in final sessions averaged
about 1 g/kg. The effect of the flavor-ethanol contingency was assessed in preference tests that offered a choice between
the two flavor solutions without ethanol. In both experiments, subjects developed a preference for the flavor that had been
paired with ethanol. Thus, the outcome of flavor conditioning was consistent with that of the oral self-administration tasks
in providing evidence of ethanol’s rewarding effects. These experiments confirm and extend previous studies showing that flavor
aversion is not the inevitable result of flavor-ethanol association in rats. It seems likely that ethanol’s nutrient and pharmacological
effects both contributed to the development of conditioned flavor preference.
Received: 15 February 1997 / Final version: 11 June 1997 相似文献
26.
There is a scarcity of well-controlled studies of the seasonal variation in circadian rhythmicity. In the present study, the circadian phase of rectal temperature and the onset of slow wave sleep were studied in a series of twelve 24-h experiments, one each month of the year, for six healthy subjects under controlled conditions in a climatic chamber. In winter, as compared with summer, the average circadian rhythm of rectal temperature was phase delayed by 45 min, and the average onset of slow wave sleep was phase delayed by 40 min. The temporal relationship between the circadian phase of rectal temperature and the timing of slow wave sleep was maintained throughout the year. Habitual rising and retiring times covaried as well. Furthermore, the circadian rhythm of rectal temperature followed the timing of the photoperiod across the year, but had a much smaller range of seasonal variation. Apparently, the seasonal variation in the photoperiodic zeitgeber is largely compensated for by the stabilizing influence of secondary zeitgebers. However, in healthy subjects some effect of photoperiodic variation can still be observed. 相似文献
27.
28.
飞行员配穿两种囊式抗荷服在不同环境温度和代谢水平时的热应激 总被引:4,自引:0,他引:4
目的 探讨飞行员配穿囊式抗荷服在不同环境温度、不同代谢水平条件下的热应激 ,为评价囊式抗荷服的热负荷和制定相应的保障措施提供理论依据。方法 6名受试者分别配穿KH - 3抗荷服及配套装备和KH - 7抗荷服及配套装备 (以下分别简称为“KH - 3”和“KH -7”) ,以不同代谢水平暴露于 2 0℃、2 5℃和 35℃环境。每次试验 70min。测量了受试者配穿KH- 3和KH - 7时的卫生学参数、皮肤温度、直肠温度、心率等 ,并以综合热应激指数 (CIHS)评定了热应激防护等级。结果 KH - 3和KH - 7的各项卫生学参数 (clo值、im、im/IJ)均无显著差别。KH - 3对照Ⅲ组和KH - 7对照Ⅳ组 (2 5℃ ,1178~ 132 5kJ·h- 115min ,36 8kJ·h- 15 5min)的CIHS均未超过生理安全限的 6 0 % (分别为 3.5 4和 3.4 6 ,属轻度热应激 ) ;KH - 3高代谢组和KH- 7高代谢组 (2 0℃ ,84 6~ 10 30kJ·h- 170min)的CIHS在生理安全限的 6 0 %~ 95 %之间 (分别为4 .2 4和 4 .6 0 ,属中度热应激 ) ;KH - 3高温组和KH - 7高温组 (35℃ ,1178~ 132 5kJ·h- 115min ,36 8kJ·h- 15 5min)的CIHS却超过生理安全限的 95 % (分别为 7.31和 7.87,属重度热应激 )。结论 受试者配穿KH - 3与KH - 7时的各项卫生学参数、热应激等均无显著差别 ,但配穿后者比 相似文献
29.
术中输注氨基酸对硬膜外阻滞复合全麻开胸手术患者围术期体温的影响 总被引:2,自引:0,他引:2
目的评价术中输注氨基酸对硬膜外阻滞复合全麻食管癌和贲门癌手术患者围术期深部体温和代谢的影响。方法择期食管癌和贲门癌手术患者21例,ASAⅠ或Ⅱ级,随机分为3组(n =7):从麻醉诱导开始至手术结束,分别静脉输注氨基酸混合液240kJ·h-1(AA组)、等容量乳酸钠林格氏液(LR组)、葡萄糖溶液240kJ·h-1(GLU组)。麻醉诱导前至术后2h每5分钟测定鼓膜温度,于麻醉诱导前即刻、手术开始后1h和术后1h检测指尖血糖,采用4分表法评价术后2h内寒战的发生情况,采用间接测热仪测定术前与术后氧耗。结果与麻醉诱导前即刻比较,术后30min LR组和GLU组氧耗降低,AA组氧耗升高(P<0.01),术后2h LR组、GLU组鼓膜温度降低(P<0.05),AA组差异无统计学意义(P>0.05);与LR组和GLU组比较,AA组术后2h内寒战发生例数减少(P< 0.05),术后30min氧耗增多(P<0.05),LR组与GLU组比较差异无统计学意义(P>0.05)。结论硬膜外阻滞复合全麻开胸手术患者术中静脉输注氨基酸可通过提高基础代谢率,缓解围术期深部体温降低,减少术后寒战发生,而输注葡萄糖不产生此效应。 相似文献
30.
张岚 《中国自然医学杂志》2002,4(3):145-146
目的 探讨气温对细菌性痢疾发病的影响。方法 应用相关回归统计法和圆形分布法对资料进行研究。结果 菌痢的月平均发病百分构成比与相应年份月平均气温呈正相关(r=0.5099,P<0.01);辖区近10年的平均气温较前10年有所上升,尤其秋冬季与初春月平均气温升高了1℃左右,而菌痢发病高峰时点明显后移(F=11.49,P<0.01),流行高峰期也有后移倾向。结论 气温对菌痢的发病有直接影响,气温升高,菌痢的发病增加,年平均气温升高可导致菌痢的发病高峰时间后移。 相似文献