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1.
目的:提高静脉留置针使用有效期,保证心血管患者得到及时用药,有效开放静脉抢救通道。方法:建立了心血管患者静脉留置针的临床护理路径(Clinical Nursing Pathway,CNP)。选择我院2018年1-12月期间接诊的静脉留置针心血管患者为研究对象,共100例,随机分组,即对照组(50例,常规护理)与实验组(50例,在常规护理基础上辅以临床护理路径),比较两组护理效果,包括留置时间、不良反应情况、患者满意度等。结果:护理后,两组患者留置时间无明显差异,但实验组不良反应发生率、静脉炎发生率低于对照组,差异有统计学意义(P<0.05);实验组满意度、一次性置管成功率高于对照组,而非计划性拔管率则低于对照组,差异有统计学意义(P<0.05)。结论:心血管患者静脉留置针护理中辅以临床护理路径,可减少不良反应,预防静脉炎,延长置管时间,提高护理满意度,值得优选。 相似文献
2.
Summary The effectiveness of nifedipine retard as a treatment for Raynaud's phenomenon was assessed in 15 patients in a placebo controlled double blind study. An associated connective tissue disease was evident in 7 patients. Changes in finger and forearm blood flow (venous occlusion plethysmography), digital skin temperature and digital systolic pressure were measured acutely before and after a 2-week treatment period. Subjective assessment of efficacy was based on patient diary data. In addition alpha2-adrenoceptor density on platelets was measured before and after chronic nifedipine therapy in both the patient group and in an age-and-sex-matched control group. No significant haemodynamic changes were observed. Nifedipine retard significantly reduced the frequency (p<0.05) with no change in either the duration or severity of vasospastic attacks. Side effects were commono following nifedipine retard. A reduction in alpha2-adrenoceptor density on platelets was observed in patients compared to a control group (p<0.05). Alpha2-adrenoceptor density was unchanged following a 2-week treatment period with nifedipine retard. This study concludes that nifedipine retard is not effective in the treatment of Raynaud's phenomenon over a short time course. Patients with Raynaud's phenomenon have reduced alpha2-adrenoceptor densities on their platelets. 相似文献
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R. L. Kaufmann R. M. Bayer C. Harnasch 《Pflügers Archiv : European journal of physiology》1972,332(2):96-116
Summary An investigation was carried out on isolated cat's papillary muscle in order to study displacement effects upon the intensity and the time course of the contractile activity. Displacements occurring before or very early during a contractile cycle produce effects which can be entirely explained on the basis of the cardiac active length-tension relation. Displacements occurring later exhibit additional effects in so far as either stretches or releases induce a drop of contractile activation such that the course of the subsequent tension development is markedly below that of the same displacement applied earlier. In order to separate these effects from those based on the active length-tension correlation experiments were performed in which very short release-stretch or stretch-release operations were applied so that the muscle length was virtually the same at the beginning and at the end of the operation. The results obtained under these conditions can be summarized as follows.The extend to which contractile tension drops after a stretch-release or a release-stretch cycle has been applied depends upon (1) the stimulus intervention interval (2) the length change performed (3) the velocity of displacement during the intervention. It is not dependent on the initial muscle length. Increasing the extracellular Ca-concentration considerably reduces the displacement effects. The results are tentatively explained by assuming an internal feedback loop between a variable of the contractile machinary and the preceding mechanism of activation.This investigation was supported by the Deutsche Forschungsgemeinschaft (grant Ka 287, 1+3). 相似文献
5.
Wolfgang Schwarz 《Pflügers Archiv : European journal of physiology》1979,382(1):27-34
The influence of temperature changes in the range of 25°C to –6°C on the time constants of Na activation (m) and inactivation (h) was studied in twitch muscle fibers and the node of Ranvier under voltage-clamp conditions. Arrhenius plots of m and h exhibit a change in activation enthalpy at temperatures below 10°C. Cooling and subsequent heating induce a hystersis in the temperature dependence of m and h Ni2+ and UO
2
2+
increase the hysteresis width. With fast temperature changes the gating kinetics relax to their new values more slowly than the temperature change. Hence, temperature must be changed more slowly than 5°C/min if an additional apparent hysteresis due simply to this relaxation is to be avoided. The data are explained by the hypothesis of a phase transition in the membrane lipids. This conception is favoured over a temperature-induced change in protein conformation, since the neutral local anaesthetic benzocaine shows use-dependent block as if low temperature restricted the access of the drug through the lipid phase to its receptor.Supported by grant NS 08174 from the U.S. Public Health Service and SFB 38 from Deutsche Forschungsgemeinschaft 相似文献
6.
A. V. van den Berg H. Collewijn 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1987,68(1):195-204
Summary We investigated the capacity of 6 humans to make voluntary smooth eye movements with a horizontally stabilized foveal point target. When the target was viewed on a dark field, all subjects were able to make smooth oscillatory eye movements when they attempted to imitate their own normal pursuit of sinusoidal target movement (0.2–0.7 Hz) directly preceding the stabilization on the fovea. The frequency of the imitating eye movement was in general lower than the frequency of normal pursuit by 2–35%. While fixating a foveally stabilized point target superimposed on a large, sinusoidally moving non-stabilized background, all subjects were able to make either no eye movements, eye movements nearly in phase with or eye movements nearly in counterphase with the background movement depending on the instruction to imagine the target as head-stationary, moving in phase, or moving in counterphase with the background. The accuracy of the frequency of the smooth eye movement with the stabilized target on the moving background was higher than during imitation of pursuit on the dark field but the precision of the frequency was lower than during normal pursuit. When the background moved pseudo-randomly all subjects could voluntarily inhibit their smooth eye movements or could make smooth eye movements in phase with the background. Only 2 subjects showed a limited ability to make smooth eye movements opposite to the pseudo-random background movement. The results suggest that with predictable background movement the volition of the subject rather than the movement of the background determines the eye movements when the subject looks at the foveally stabilized target. 相似文献
7.
Summary The effect of a selective irradiation of myelin by3H -particles was studied by light and electron microscopic methods in guinea pig spinal cord. The animals were injected with [3H]leucine shortly after birth when the rate of myelin biosynthesis is high and sacrificed 130 days later. In spinal cord the radioactivity was mainly preserved in myelin because the half life of myelin proteins is much higher than that of most other CNS protein. As a consequence the irradiation dose in the white matter was much higher than in the gray matter. In myelin internally irradiated by3H -particles within 130 days at a dose of 10 Gy no alterations could be detected either by morphological or by morphometric methods.Supported by the Deutsche Forschungsgemeinschaft 相似文献
8.
本文分析经皮球囊二尖瓣成形术治疗风湿性二尖瓣狭窄的疗效。结果表明 ,PBMV耗费少 ,住院期短。效果良好 ,值得推广应用 相似文献
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10.
Noradrenaline transport by rat heart sympathetic nerves: A re-examination of the role of sodium ions
Sergio Sánchez-Armáss Fernando Orrego 《Naunyn-Schmiedeberg's archives of pharmacology》1978,302(3):255-261
Summary The effect of sodium ion on 3H-(–)-noradrenaline (0.0875 to 0.5 M) transport by rat heart atrial hemi-appendages incubated in vitro has been studied, and the following observations made: a) When sodium was omitted (choline and lithium substitution) there was no evidence for active noradrenaline transport, and only a component that did not show saturation kinetics up to 1 M noradrenaline, remained. b) Omission of sodium or addition of 4×10–5 M desipramine inhibited noradrenaline transport to exactly the same extent, and their effects were not additive. Alprenolol did not reduce this sodium-independent transport, but tropolone lowered it somewhat. c) No evidence for corticosterone-sensitive noradrenaline transport (uptake-2) was found in this preparation at the low amine concentrations used. d) In control medium, the kinetic parameters of transport were: K
m: 0.59 ± 0.063 M and V
max: 2.44 ± 0.43 (pmoles/mg protein/min). With 26 mM sodium and the rest substituted by choline, K
m:2.26 ± 0.70 M (P0.001) and V
max: 2.74 ± 0.43 (pmoles/mg protein/min) (not significant). Also with 26 mM sodium, but with sucrose substitution, K
m: 0.76 ± 0.13 M (N.S.) and V
max: 1.06 ± 0.13 (pmol/mg/min) (P<0.05). Such results indicate that sodium only modifies the affinity of the transport system for noradrenaline, without changing V
max, and that changes in the latter are only a consequence of a reduction of the ionic strength. e) When noradrenaline transport was studied at different concentrations of external sodium, at constant ionic strength and with precautions to minimize the noradrenaline-releasing effect of low sodium, it was found that the data could be best represented by two hyperbolas placed in series. This suggests that the noradrenaline carrier has two sites for sodium, that do not interact with each other. When the same experiments were repeated in the absence of chloride, it was found that the noradrenaline transport system had lost virtually all its affinity for sodium. f) The effect of prolonged tissue incubation in the absence of sodium was found to produce a relatively small inactivation of noradrenaline transport. Such phenomenon was enhanced by raising the calcium concentration to 2 mM. 相似文献