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111.
带监测皮岛腓骨移植治疗股骨颈骨折 总被引:1,自引:0,他引:1
目的:探讨监测皮岛腓骨移植治疗股骨颈骨折的临床价值。方法:用带监测皮岛的腓骨移植结合AO空心钉内固定治疗11例中青年股骨颈骨折患者。结果:11例中1例监测皮岛于术后监测过程中准确地提示移植腓骨血管危象,及时手术探查处理,复通血供。11例监测皮岛全部成活,随访1~3年,股骨颈骨折端骨愈合,股骨头无坏死。结论:带监测皮岛吻合血管的腓骨移植治疗股骨颈骨折疗效可靠,监测皮岛是腓骨移植术后血供监测的可靠方法。 相似文献
112.
Effects of Beta-Adrenergic Activity on T-Wave Amplitude 总被引:1,自引:0,他引:1
Richard J. Contrada David S. Krantz Lynn A. Durel Linda Levy Patrick J. LaRiccia Judith R. Anderson Theodore Weiss 《Psychophysiology》1989,26(4):488-492
This study addresses the hypothesis that electrocardiographic T-wave amplitude is influenced by beta-adrenergic stimulation of the heart. Beta-adrenergic activity was manipulated both pharmacologically and through behavioral challenge. Under resting conditions, 12 healthy men underwent infusion of placebo and then the beta-agonist, isoproterenol, and the beta-blocker, propranolol, in a counterbalanced, crossover design. During infusion of placebo, subjects also underwent two behavioral challenges, a structured interview and mental arithmetic. Analysis of the resting data indicated that propranolol produced a significant increase in T-wave amplitude, and isoproterenol produced significant T-wave amplitude attenuation. As previously reported, drug effects were also in evidence for heart rate. Behaviorally-induced reduction of T-wave amplitude was observed for mental arithmetic but not structured interview, which again paralleled heart rate data. Both pharmacological and behavioral data reported in this study support the hypothesis that the T-wave is significantly affected by beta-sympathetic influence on the heart. However, a nonspecific effect of heart rate change on T-wave amplitude would also account for these results. The findings are discussed in terms of their implications for the utility of T-wave amplitude in psychophysiological research. 相似文献
113.
M. E. Verberne A. C. Gittenberger-de Groot R. E. Poelmann 《Anatomy and embryology》1998,198(3):171-184
We were interested in the contribution of the cardiac neural crest to the complete anterior and posterior nerve plexus of
the chick heart. This includes the pathways by which these cardiac neural crest-derived neuronal precursors enter the heart.
As lineage techniques we used the traditional quail-chick chimera in combination with the newly introduced technique of retroviral
reporter gene transfer to premigratory cardiac neural crest cells. Retrovirally infected embryos (n=23) and quail-chick chimeras (n=19) between stages HH27 and 40, were immunohistochemically evaluated, using the lineage markers LacZ (retroviral reporter)
and QCPN (anti-quail nuclear marker), respectively and the neuronal differentiation markers HNK-1, RMO-270 and DO-170. Between
stages HH27 and 33, quail-derived and LacZ positive cells were situated around the arterial cardiac vagal branches at the
arterial pole, and vagal branches along the anterior cardinal veins and the sinal vagal branch at the venous pole. From stage
HH35 onward, QCPN/LacZ-positive cardiac ganglia were observed throughout the anterior and posterior plexus and were mainly
concentrated in the subepicardium near the distal ends of the arterial cardiac vagal branches and the sinal cardiac vagal
branch respectively. From stage HH36 both the anterior and posterior plexus contained a population of large cardiac ganglion
cells and a population of smaller cells along nerve branches as well as in the cardiac ganglia, which means that differentiation
starts in both plexus at the same time. Furthermore only nerve fiber connections between the anterior and posterior plexus
were observed. These results show that the cardiac neural crest contributes to the cardiac ganglion cells from both the entire
anterior and posterior plexus. Furthermore these results suggest that these precursor cells enter the arterial pole via the
arterial cardiac vagal branches and the venous pole via the sinal cardiac vagal branch without intermixing. Finally we show
that in addition to the cardiac ganglia, the cardiac neural crest contributes to small myocardial glia or undifferentiated
cells along nerve fibers, and some myocardial nerve fibers as well as nerve tissue in the adventitia of the large veins at
the venous pole and in the adventitia of the coronary arteries.
Accepted: 30 March 1998 相似文献
114.
Balvinder S. Jassar Peter A. Smith 《Pflügers Archiv : European journal of physiology》1991,419(5):478-485
The afterhyperpolarization (AHP) which follows the action potential (AP) in bullfrog sympathetic ganglion B-cells involves activation of Ca2+-sensitive K+ conductances following Ca2+ influx via Ca2+ channels. The duration of AHPs evoked at 2-s stimulus intervals were 70.05±3.76% of those evoked at 90-s stimulus intervals (n=35). Since there was no consistent effect of ryanodine (5 M), ruthenium red, (300 M) or dantrolene Na (35 M) on this frequency dependence, it is unlikely to result from release of Ca2+ from intracellular stores. Ca2+ currents (I
Ca, studied by means of the whole-cell patch-clamp technique, exhibited a slow frequency dependence as a result of a slow inactivation process which was independent of Ca2+-induced I
Ca inactivation and I
Ca run-down. There was excellent correlation (r=0.964) between the estimated changes in Ca2+ influx and the expected activation of the Ca2+-sensitive K+ current, I
AHP. This result is consistent with the hypothesis that the frequency dependence of the AHP is a consequence of the slow inactivation of I
Ca. 相似文献
115.
I. Rodriguez-Moldes J. P. Timmermans D. Adriaensen M. H. A. Groodt-Lasseel D. W. Scheuermann R. Anadon 《Anatomy and embryology》1990,181(4):389-391
Summary Using an antibody raised against a purified chick duodenal vitamin D-dependent calcium-binding protein, the presence and distribution of calbindin has been studied immunohistochemically in the habenular ganglia of the dogfish. In the more developed left ganglion, a positive reaction was clearly observed in the neurons of the medial nucleus, whereas in the lateral nucleus, only some scarce, hardly immunostained cells appeared. In the neurons of the right habenula however, no immuno-reactivity was observed. The distribution of vitamin D-dependent calcium-binding protein in the dogfish habenulae is therefore asymmetrical. This may be due to differences in the neuronal activity between the two ganglia. 相似文献
116.
Inger B. Schipper Paul Steendijk Robert J. M. Klautz Enno T. van der Velde Jan Baan 《Pflügers Archiv : European journal of physiology》1993,425(5-6):426-433
It has been shown that in the intact canine heart the left-ventricular end-systolic pressure/volume relation (ESPVR) depends on loading conditions: an increase in arterial vascular resistance causes a leftwards shift and a steeper slope of the ESPVR, suggesting an increased inotropic state. Our purpose was to investigate the possible contribution of the sympathetic nervous system to this load sensitivity of the ESPVR, using intact, but denervated, hearts with normal coronary perfusion and afterload. We used two types of loading intervention: venous volume infusion and gradual occlusion of the descending aorta. ESPVRs were obtained in six anaesthetized open-chest dogs, both before and after bilateral ablation of the stellate ganglia. To exclude the influence of heart rate changes, bilateral vagotomy was performed and the heart was paced. The absence of (unpaced) heart rate changes in response to pressure alterations was used to confirm total denervation. Left ventricular pressure was measured with a micromanometer and volume with a conductance catheter. ESPVRs were essentially linear and characterized by their slope (E
es) and volume intercept at 12 kPa (V
12). We found that E
es (P<0.0001) and V12 (P<0.05) were both significantly different during pressure and volume interventions (0.67±0.29 and 0.41±0.18 kPa/ml for E
es and 16.2±8.2 and 18.2±8.4ml for V12 respectively). Denervation did not significantly affect the parameters of the ESPVR obtained by either volume infusion or aortic occlusion. Two-way analysis of variance revealed no significant interactive effect between denervation and intervention, indicating that the sympathetic nervous system does not influence the load dependency of the ESPVR. The dP/dt
max: EDV relationship behaved similarly. These results suggest that load dependency is an intrinsic property of the myocardium. 相似文献
117.
Buchs A Slovik Y Rapoport M Rosenfeld C Khanokh B Nitzan M 《Medical & biological engineering & computing》2005,43(2):252-257
Photoplethysmography (PPG) records the cardiac-induced changes in tissue blood volume by light-transmission measurements.
The baseline and amplitude of the PPG signal show very low-frequency (VLF) spontaneous fluctuations, which are mediated by
the sympathetic nervous system, and high correlation between right and left extremities of healthy subjects. As sympathetic
neuropathy is one of the diabetic complications, the right-left correlation of the PPG fluctuations was examined in diabetic
patients. The PPG signal was simultaneously measured in the two index fingers and the two second toes of 35 diabetic patients
and 33 non-diabetic subjects. For each PPG pulse, the baseline and amplitude were determined, and the right-left correlation
coefficients of the VLF fluctuations in the baseline and amplitude were derived. The VLF fluctuations in the baseline showed
high right-left correlation, both for fingers (0.93±0.05) and toes (0.93±0.06), for the non-diabetic subjects, and significantly
lower correlation (0.78±0.22 and 0.84±0.17, respectively) for the diabetic patients. Similar results were obtained for the
amplitude VLF fluctuations. The right-left correlation coefficients for diabetic patients decreased with the disease duration
for the toe baseline and toe amplitude fluctuations and correlated with heart rate response to deep breathing for the finger
baseline and toe amplitude fluctuations. The right-left correlation coefficients of the PPG fluctuations provide a simple
and convenient means for assessing the adequacy of the sympathetic nervous system function. 相似文献
118.
目的探讨距骨颈骨折治疗方案的选择以及疗效相关因素分析。方法距骨颈骨折15例,男13例,女2例。年龄16~63岁,平均40.5岁,合并腰椎、髋臼、跟骨、外踝骨折各1例。开放骨折2例。陈旧性骨折2例(〉1个月)。按Hawkins骨折分类:Ⅰ型3例、Ⅱ型9例、Ⅲ型3例。Ⅰ型骨折采用膝下管型石膏固定,其中1例复诊中因移位行切开复位松质骨螺钉固定。Ⅱ型骨折均行切开复位,克氏针或松质骨螺钉固定。Ⅲ型骨折1例开放性骨折,急诊行清创缝合,手法+撬拔复位,脱位整复。一周后在C臂机引导下,采用二枚直径4.0mm中空螺钉由后向前固定距骨颈,1例急诊手术切开复位,克氏针内固定。结果本组13例获得随访,时间4~24个月,平均12.3个月。13例中发生距骨体缺血性坏死5例,其中Ⅱ型骨折4例,Ⅲ型骨折1例。另2例未统计在内。1例外院病例术后并发伤口感染长期不愈,行小腿截肢术。1例患者拒绝手术治疗。按Hawkims疗效标准,优4例,良4例,可3例,差2例,优良率69%。结论对无移位的距骨颈骨折,行膝下管型石膏固定6~12周,并定期拍片复查,距骨颈骨折脱位应急诊复位和可靠的内固定。以2枚拉力螺钉内固定为宜,尽量减少并发症。对距骨体缺血性坏死,或创伤性关节炎,则根据患者的实际情况采取相应治疗措施。 相似文献
119.
Arnaldo Ferroni A. Galli M. Mazzanti 《Pflügers Archiv : European journal of physiology》1996,431(6):954-963
Neuronal cell firing is crucial to nerve-nerve communication. The ability to produce consecutive action potentials is related
to the activation of inward currents after each upstroke. If fast Na current is indeed responsible for the overshoot, it is
still unclear which current drives membrane voltage to the Na threshold. In this study we present evidence that in adult rat
sensory neurones a dihydropyridine-sensitive Ca channel exists in addition to the well characterized L-type, or high-threshold
Ca channel. During stimulated action potential trains, L-type Ca channels open during the excitation wave, whereas activity
of the other dihydropyridine-sensitive Ca channel was observed primarily between action potentials. This second Ca pathway
shows remarkably long openings at negative potentials after a series of positive prepulses. The nerve action potential and
the repetitive firing work as a physiological Ca channel facilitation mechanism. Therefore, we suggest that this novel Ca
conductance provides inward current, between two consecutive action potentials, able to modulate the frequency of neuronal
bursts.
Received: 3 August 1995/Received after revision: 9 October 1995/Accepted: 10 October 1995 相似文献
120.
目的 探讨AO加压空心钉治疗股骨颈骨折的临床疗设。方法 对79例股骨颈骨折患者均采用AO加压空心钉治疗。结果 所有病人都获得随访,随防时间6个月~4年,按马元障功能恢复分级.优45例.良26例,差8例.总优良率88.7%。结论 AO加压空心钉治疗股骨颈骨折方法简单.疗效确切,值得提倡。 相似文献