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51.
O. E. Osadchii V. M. Pokrovskii O. G. Kompaniets A. N. Kurzanov 《Bulletin of experimental biology and medicine》1997,123(5):427-430
Administration of neurotensin against the background of sinus arrhythmia caused by burst stimulation of the vagus nerve in
cats restores synchronization of the cardiac and vagal rhythms or modulates the proportion between them. This either stops
the arrhythmia or changes its parameters. The effects of the peptide are similar to those of epinephrine and are abolished
by β-adrenoreceptor blockage.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 123, No. 5, pp. 494–497, May, 1997 相似文献
52.
蝶窦居于颅底,毗邻结构复杂,常有变异。本文报告开展各类型蝶窦手术125例,并就蝶窦区域应用解剖对蝶窦手术的重要性,进行研究与探讨。 相似文献
53.
目的分析脑静脉血栓(CVT)病人的死亡原因。方法回顾分析136例CVT病人中5例死亡病例的病因、临床表现、影像学资料、治疗经过及死亡原因。结果病死率为3.7%。2例在急性期死亡,3例在慢性期死亡。直接死亡因素均为脑疝;间接死亡因素为颅内多发性出血和多个部位的脑静脉血栓形成,死亡组(3.20±0.84)支静脉受累,存活组(2.09±1.00)支静脉受累(P=0.016)。而性别、年龄、确诊时间、癫疒间发作、病灶部位及治疗前颅内压等没有显著增加死亡的危险性。某些临床表现,如失语、运动障碍、精神症状及意识障碍与死亡有关,但其系多发性颅内出血及多个部位脑静脉血栓所致。结论CVT病人的直接死亡原因为脑疝,间接原因为多发性脑静脉血栓和颅内多发性出血。死亡不仅可以发生在急性期,也可以出现在慢性期。 相似文献
54.
Zhang Deli Chen Shulan 《宁夏医科大学学报》1987,(2)
Sinoatrial node electrogram (SNE) was recorded successfully in recent years, using transvenous electrode catheter. Via SNE and intratrialelectrogram (IEG), one could measure sinoatrial conduction time(SACT) directly, observe sinoatrial node (SN) potential changes in cadiac cycles, diagnose some sinus arrhythmias which couldn't be confirmed by surface ECG. All these could offer accurate evidence for differential diagnosis of sick sinus syndrome (SSS). The authors recommend a modified method for the location of the electrode catheter, by which one can increase success rate of obtaining stable SNE. Using this method, the authors recorded SNE in 10 cases with SSS successfully. 相似文献
55.
三种去神经法对清醒大鼠动脉压力感受性反射功能的影响 总被引:3,自引:0,他引:3
目的:测定急、慢性去主动脉神经(AD)、去颈动脉窦神经(SD)、同时去主动脉和窦神经(SAD)后大鼠动脉压力感受性反射对血压控制(ABR-BP)和心动周期控制(ABR-HP)的影响。方法:测定ABR-BP采用阻断动脉压力感受性反射传出通路前后,比较机体对去氧肾上腺素升压反应面积差异的方法,所得数值与改良的Smyth方法测定的ABR-HP值进行比较。结果:(1)大鼠SAD后ABR-HP为零,且代偿不明显;而ABR-BP约为30%,且代偿明显;(2)SD后ABR-BP与ABR-HP无显著差异,而AD和SAD后ABR-BP的作用显著大于ABR-HP的作用。结论:(1)大鼠的ABR-HP传入冲动全部来自于主动脉弓和颈动脉窦的压力感受器,而ABR-BP传入冲动大部分来自于这两处的感受器;(2)主动脉神经和窦神经感受传入在ABR-BP中的作用是相当的,并有明显的相互代偿;而在ABR-HP中,主动脉神经的作用比窦神经重要,其代偿能力也比窦神经显著。 相似文献
56.
本文复习20例出血坏死性上颌窦炎的CT表现,笔者认为特征性CT表现为:上颌窦与鼻腔内软组织肿块;窦腔的不均等性膨胀扩大;窦壁骨质吸收或破坏,此外,对出血坏死性上颌窦炎同上颌窦癌的CT鉴别作了讨论 相似文献
57.
The influence of intravenous magnesium sulphate on the occurrence of atrial fibrillation after coronary artery by-pass operation 总被引:5,自引:1,他引:4
PARIKKA H.; TOIVONEN L.; PELLINEN T.; VERKKALA K.; JARVINEN A.; NIEMINEN M. S. 《European heart journal》1993,14(2):251-258
To examine the influence of (Mg) on hypomagnesaemia and atrialfibrillation (AF) following coronary artery by-pass surgery,140 consecutive patients were randomized to receive 70 mmolof magnesium sulphate intravenously (n = 69) or placebo (n =71). Serum magnesium concentrations fell to 0.77 ± 0.10mmol. l1 in the control group but rose to 1.09 ±0.17 mmol. l1 in the Mg group (P <0.001). The incidenceof AF was 29% in the Mg group and 26% in the placebo group (NS).The AF patients were older, more of them had had prior AF episodes,their sinus rates (SR) were slower (78 ± 10 vs 86 ±12 beats. Min1; P <0.01) and serum Mg concentrationshigher (0.89 ± 0.21 vs 0.11 mmol. l1; P <0.05)The incidence of AF was 43% in the highest quartile of serumMg and 23% among the rest (P = 0.056). In patients experiencingAF during the first three post-operative days, serum Mg concentrationswere higher and SR slower on each day compared with non-AF patients.SR increased post-operatively less with high Mg levels (P =0.044). In the Mg group, serum Mg and SR were the only independentpredictors of AF. In conclusion, the incidence of post-operativeAF is not decreased with magnesium. High Mg levels are likelyto provoke AF probably by mechanisms that modify SR. 相似文献
58.
N. Hirabuki T. Miura M. Mitomo K. Harada T. Hashimoto R. Kawai T. Kozuka 《Neuroradiology》1988,30(5):390-394
Summary Four patients with dural arteriovenous malformation (AVMs) draining into the cavernous sinus, who presented ophthalmic manifestations, were studied by magnetic resonance (MR) imaging. In all patients signal decrease in the involved cavernous sinus was demonstrated in coronal spinecho (SE) imaging. It is attributable to rapid venous flow in the sinus, and this high velocity signal loss is a fairly pathognomonic finding in this condition. We stress the validity of MR imaging in the primary diagnosis of dural AVMs with ophthalmic symptoms. 相似文献
59.
PAOLO ALBONI NELLY PAPARELLA RICCARDO CAPPATO PAOLO PEDRONI GIAN CARLO CANDINI GIAN ENRICO ANTONIOLI 《Pacing and clinical electrophysiology : PACE》1989,12(2):294-300
The purpose of this study was to find out whether transesophageal pacing could be utilized for assessment of sinus node function in patients with sick sinus syndrome (SSS). In 17 patients with SSS (study group) we compared the results of sinus node tests obtained both in the basal state and after pharmacological autonomic blockade by endocavitary stimulation and, 24 hours later, by transesophageal pacing. In another group of 17 patients with SSS (control group), we compared the results obtained by two endocavitary studies. In "study group", sinus cycle length (SCL) and corrected sinus node recovery time (CSRT) did not show significant differences between the two studies both in the basal state and after autonomic blockade, whereas sinoatrial conduction time (SACT) was more prolonged during esophageal pacing (P less than 0.01). In "control group", sinus node measures did not show significant differences between the two studies. In the "study group," the following coefficients of correlation were obtained in the basal state; SCL, r = 0.65, CSRT, r = 0.57, SACT, r = 0.52 and after autonomic blockade: SCL, r = 0.95, CSRT, r = 0.62 and SACT, r = 0.53. In the basal state, the correlation for SCL and CSRT between the two studies was lower in the "study group" than in the "control group" (P less than 0.05), whereas after autonomic blockade the correlation for sinus node measures did not show significant differences between the two groups of patients. These data suggest that transesophageal study influences the autonomic tone regulating the sinus node; however, it is not responsible for important variations in sinus node measures.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
60.
In humans, electrical, bipolar, bilateral carotid sinus nerve stimulation (CSNS; impulse duration 0.35 ms) was applied, using frequencies between 10 and 110 Hz and voltages between individual thresholds and maximal amplitudes of stimulation. Ten anginal patients and two hypertensive patients were studied at an interval of up to 12 years after implantation of electrodes and a radiofrequency receiver for chronic therapeutic CSNS. In search of combinations of frequency and voltage of CSNS, eliciting largest ("optimal") depressor responses of blood pressure and heart rate in the individual patient, Rechenberg's evolution strategy was applied. This strategy simulates mutation and selection of biological evolution. In each patient and on each test stimulation, a value of quality was computed from actual heart rate and blood pressure values as a selection criterion for the strategy. Either responses to uninterrupted CSNS were investigated, while stimulation parameters were adjusted every 3 min, according to the strategy, or responses to 3 min of CSNS after a change in stimulation parameters were compared to intercalated 3-min control periods. In each patient, one or more combined settings of frequency and voltage elicited "optimal" responses. In principle, "optimal" CSNS frequencies ranged between 35 and 105 Hz with large interindividual differences. Due to chronic implantation of electrodes and technical features of radiofrequency transmitted stimulation energy, interindividually different voltages led to an optimal response to CSNS. Also according to the present results, the frequency of CSNS has to be determined individually. It is concluded that the evolution strategy was applied successfully, because voltage and frequency settings leading to "optimal" responses were found within 90-180 min, whereas intraindividual systematic investigations would not be feasible due to their necessarily very long duration. So far, only short-term responses have been evaluated. A broader use of the strategy in other applications is encouraged, as for example in pacemaker optimization and especially in functional electrostimulation. 相似文献