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排序方式: 共有1170条查询结果,搜索用时 15 毫秒
81.
VERONIQUE MAHAUX YVES VERBOVEN RE WALEFFE HENRI KULBERTUS 《Pacing and clinical electrophysiology : PACE》1992,15(11):1862-1866
A sensor driven algorithm limiting ventricular pacing rate during supraventricular tachycardia (SVT) is included in a dual chamber rate modulated pacemaker sensitive to acceleration forces (Relay, 294-03, Intermedics Inc.). According to the intensity of concomitant exercise, the ventricular pacing rate is limited either to the programmed maximum pacing rate (MPR) or to an interim lower limit, called "conditional ventricular tracking limit" (CVTL). The MPR prevails over the CVTL when the sensor calculated pacing rate exceeds the minimal rate by more than 20 beats/mm. The purpose of the study is to determine the clinical safety and efficacy of this algorithm in patients with intermittent SVT. Method: a Relay was implanted in four patients with a bradycardia/tachycardia syndrome and in four patients with complete atrioventricular block (CAVB). All had episodes of paroxysmal atrial tachycardia. The units were programmed in DDDR: rate responsive parameters were adjusted by simulating the rate response during three levels of exercise to let the MPR override the CVTL only during strenuous exercise. Holter monitors and exercise testings were performed at 3-month follow-up. Results: in seven patients, Holter recordings showed Supraventricular arrhythmias at rest with a ventricular pacing rate limited to the CVTL. Appropriate rate increases during exercise testings were also demonstrated. Three devices had to be reprogrammed in DDIR tone patient suffering from nearly permanent atrial flutter and two patients not tolerating the CVTL pacing rate at rest). Conclusion: the CVTL algorithm is effective in protecting against high ventricular pacing rates during Supraventricular arrhythmias. It allows the selection of the DDDR mode even with a high MPR in patients with intermittent SVT. 相似文献
82.
ALADAR RONASZEKI HUGO ECTOR BOUDEWIJN DENEF RE E. AUBERT VAN DE WERF HILAIRE DE GEEST 《Pacing and clinical electrophysiology : PACE》1990,13(12):1728-1731
RONASZEKI, A., ET AL.: Effect of Short Atrioventricular Delay on Cardiac Output. Short atrioventricular (AV) delay modifies late diastolic filling dynamics. The effect of this change on cardiac output [CO) was studied in closed chest, AV blocked canine preparations (N: 10), during AV sequential pacing (80 bpm). CO (thermodilution technique) and transmitral flow velocity (TMFV, pulsed-wave Doppler) were measured and compared (paired t-test) on the basis of TMFV pattern, when atrial contraction (A wave) started just after early diastolic transmitral flow deceleration [PR:219 ± 25 ms, mean ± SD) and when A wave occurred at the end of late diastole and shortened due to the next ventricular contraction (PR: 56 ± 11 ms). The short AV delay resulted in 12.0 ± 5.9% decrease of CO, reflecting the interrupted late diastolic atrial transport. Properly timed atrial contraction is necessary for optimal AV sequential pacing. 相似文献
83.
Coxon RE; Fekade D; Knox K; Hussein K; Melka A; Daniel A; Griffin GG; Warrell DA 《QJM : monthly journal of the Association of Physicians》1997,90(3):213-221
Severe Jarisch Herxheimer reaction (J-HR) precipitated by antibiotic
treatment of louse-borne relapsing fever (LBRF) is associated with a
transient, marked rise in circulating tumour necrosis factor alpha (TNF
alpha), interleukin 6 (IL-6) and interleukin 8 (IL-8). Ovine polyclonal
anti-TNF alpha antibody fragments (Fab) were used in a randomized double
blind placebo controlled trial in an attempt to prevent this reaction.
Within 4 h after penicillin, in controls (n = 29), a several- fold rise in
cytokines occurred, concomitant with a fall in spirochaetes and maximal
clinical manifestations of the J-HR. An intravenous infusion of anti-TNF
alpha Fab, 30 min before penicillin in 20 patients reduced peak plasma
levels of IL-6 and IL-8 (but not IL-1 beta) compared with controls (p =
0.01 and < 0.001, respectively) and the incidence of the J-HR,
indicating some neutralization of TNF alpha. An apparent fall in TNF alpha
reflected interference of anti-TNF alpha in the immunoassay.
相似文献
84.
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86.
J E Johnson G T Anders H M Blanton C E Hawkes B A Bush C K McAllister J I Matthews 《The American review of respiratory disease》1990,141(3):618-622
To confirm the presence of exercise dysfunction in patients seropositive for the human immunodeficiency virus (HIV), 32 such patients without AIDS were evaluated with cardiopulmonary exercise testing, pulmonary function testing, bronchoalveolar lavage, chest roentgenography, and gallium scanning. No evidence of pulmonary opportunistic infection was found. When compared to an otherwise similar group of HIV-seronegative controls, the patients exercised to a significantly lower workload (195 +/- 30 versus 227 +/- 31 W, p less than 0.001). The ventilatory anaerobic threshold (VAT) values were also significantly lower for the patients (49.2 +/- 13.0 versus 61.9 +/- 9.1% of maximum predicted VO2, p less than 0.001). Nine of the patients had VAT values less than the 95% confidence interval for the controls. This subgroup exercised to a significantly lower maximum VO2 (69.9 +/- 11.2 versus 95.9 +/- 17.5% of maximum predicted VO2, p less than 0.001) and workload (165 +/- 21 versus 227 +/- 31 W) when compared to the control group. These patients demonstrated a mild tachypnea throughout exercise relative to the controls and had a significant increase in the slope of the heart rate to VO2 relationship. These findings are most consistent with a limitation of oxygen delivery to exercising muscles, which may represent occult cardiac disease in this group. 相似文献
87.
Major complications after 400 continuous popliteal sciatic nerve blocks for post‐operative analgesia
V. COMPÈRE N. REY O. BAERT A. OUENNICH V. FOURDRINIER X. ROUSSIGNOL R. BECCARI B. DUREUIL 《Acta anaesthesiologica Scandinavica》2009,53(3):339-345
Background: A continuous popliteal sciatic nerve block (CPSNB) has been performed with increasing frequency for post‐operative analgesia after foot surgery. Major complications associated with the placement of a perineural catheter remain rarely studied. The aim of this study was to prospectively determine the incidence of major complications (neurological and infectious) in post‐operative adult patients with a continuous popliteal catheter inserted by the anatomical posterior approach for analgesia after foot surgery. Methods: All popliteal catheters were placed pre‐operatively under sterile conditions with the aid of a nerve stimulator technique. The primary outcome measure was the incidence of major complications including infection and neuropathy. As a secondary outcome, adverse effects as well as other complications were also evaluated. Data were expressed as median [25th–75th percentiles]. Results: A total of 400 patients were included in the study during a 2‐year period. The median time the catheter remained indwelling was 47 h [23, 54]. Major complications included three events (0.75%) with one infection (0.25%) and two neuropathies (0.50%). Three blocks were unsuccessful and the catheter insertion was difficult in 12 patients (3%). During the CPSNB procedure, one patient reported slight paraesthesia during stimulation. Patient satisfaction was scored at 4 for 89%, 3 for 6% and 2 for 5% on the analogue scale. Conclusions: Major complications after the use of CPSN are not in fact rare. The incidence of severe neuropathy or infection complications is, respectively, 0.50% and 0.25%. However, the insertion of CPSN could be considered effective and is associated with only a few minor complications. 相似文献
88.
目的:探讨三维适形放疗结合锎(252Cf)中子腔内后装照射治疗中晚期食管癌的疗效、不良反应及晚期并发症。方法:92例中晚期食管癌患者全部采用三维适形放疗结合锎(252Cf)中子腔内后装照射治疗。三维适形放疗总剂量为45Gy-54Gy,分25-30次,5-6周完成;腔内照射3-4Gy/次,1次/周,共2-4次,总吸收剂量10Gy-16Gy。结果:治疗结束3个月进食梗阻缓解率为95%。近期疗效:完全缓解(CR)27%,部分缓解(PR)69.6%。1、2、3年局部控制率分别为82%、51%、32%;1、2、3年生存率分别为:78%、35%、18%;急性放射性食管炎发生率为54%;晚期食管狭窄发生率9%;食管穿孔发生率2%。结论:中晚期食管癌采用三维适形放疗结合锎(252Cf)中子腔内后装照射能够迅速而持久地缓解进食梗阻症状,提高局部控制率及生活质量,近期疗效显著,放疗不良反应未见明显增加。 相似文献
89.
目的 了解应用IHA、ELISA检测鼠疫F1抗体的一致性,评价方法的优劣,以便更好地制订鼠疫监测的方法及防治策略.方法 对广西鼠疫监测点隆林、西林县的犬血清使用IHA及ELISA两种试验方法,并进行一致性研究,评价IHA与ELISA方法的可靠性.结果 IHA检测鼠疫F1抗体阳性率为0,ELISA检测鼠疫F1抗体的总阳性率为4.4%(12/273);IHA与ELISA之间的一致性为95.6%,其Kappa值等于0,呈轻度一致.结论 间接血凝试验方法特异、操作简便是传统的鼠疫监测手段之一;酶联免疫吸附试验具有敏感性高、特异性强、操作简便等特点,且与间接血凝试验有轻度一致性,适宜在鼠疫监测中推广应用. 相似文献
90.
Birman D Beehler S Harris EM Everson ML Batia K Liautaud J Frazier S Atkins M Blanton S Buwalda J Fogg L Cappella E 《The American journal of orthopsychiatry》2008,78(1):121-132
The development of evidence-based mental health interventions for refugees is complicated by the cultural and linguistic diversity of the participants, and the need to balance treatment of past traumatic experiences with ongoing support during the process of acculturation. In an effort to gather "practice-based evidence" from existing mental health services for refugees, a collaborative study of International Family, Adult, and Child Enhancement Services (FACES), a comprehensive, community-based mental health program working with refugee children, was conducted to describe the program participants and service delivery model and to assess whether participants improved over time as a function of services. Results showed that participants improved, but that the improvement was not related to dosage of services. Implications of these findings for refugee mental health services are discussed and suggestions are made for future evaluation research of mental health services with refugees. 相似文献