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91.
S. Aziz L. A. Soine S. L. Lewis A. P. Kruse W. C. Levy K. M. Wehe D. P. Fishbien M. D. Allen 《Transplant international》1997,10(6):446-450
A review of factors contributing to early mortality after cardiac transplantation revealed that up to 25 % of deaths were
due to primary graft dysfunction unrelated to rejection or infection. In light of this finding, evaluation of a donor heart
with regard to its suitability for transplantation takes on added importance. In an effort to screen the suitability of donor
hearts in the region covered by the Northwest Organ Procurement Agency (USA), all donors are evaluated by two-dimensional
transthoracic echocardiography as part of the initial evaluation. A total of 110 donor echocardiograms were reviewed and an
attempt was made to correlate the 30-day outcome with the parameters measured. An unexpected finding was that the presence
of left ventricular hypertrophy in the donor heart was associated with an increase in the incidence of donor heart dysfunction
compared with donors with normal echocardiographic profiles (33 % vs 3 %, P = 0.007).
Received: 12 February 1996 Received after resision: 27 June 1997 Accepted: 14 July 1997 相似文献
92.
K. Hamano Hiroshi Ito Andrew Bushell Kathryn J. Wood Kensuke Esato 《Transplant international》1997,10(4):293-298
In this study, the effect of combining anti-CD4 monoclonal antibody (mAb) and cyclosporin (CyA) therapy at the time of transplantation
was examined. A mouse cardiac allograft model was used. Anti-CD4 mAb administered perioperatively induces long-term survival.
The addition of a short course of CyA given subcutaneously in a regimen of either a high-dose treatment or a standard dose
treatment to the anti-CD4 mAb treatment protocol did not have a detrimental effect on graft survival. Despite having no significant
effect on graft survival, the addition of CyA to the treatment protocol did result in a significant decrease in the level
of IL-2 present in the hearts 7 days after transplantation. The decrease in IL-2 production was directly related to the presence
of CyA in vivo. When CyA treatment was continued throughout the period during which unresponsiveness to the graft is induced
by anti-CD4 mAb therapy, 50 % of the grafted hearts were rejected once the CyA was discontinued. In conclusion, the combined
use of anti-CD4 mAb therapy and CyA did not have a negative effect on graft survival in this model when the two agents were
used concurrently at the time of transplantation.
Received: 2 October 1996 Received after revision: 31 January 1997 Accepted: 5 February 1997 相似文献
93.
Hilary Eadon Marlene Rose Richard O'Neill Neil Leaver Magdi Yacoub 《Transplant international》1995,8(1):35-40
Pharmacokinetic profiles were obtained for 16 heart or lung recipients following the administration of identical doses of cyclosporin as oral solution and capsules on consecutive days. A comparison of pharmacokinetic parameters (AUC, Cmax, Cmin and tmax) showed that there were no significant differences between the two formulations except for the tmax, which was significantly longer for the capsules. The mean variation in day-to-day trough levels produced by the two different forms was 25.6%. A retrospective study was carried out of consecutive cyclosporin levels in patients at steady state on oral solution. The mean variation in day-to-day trough levels was 32.3%. This was not significantly different from the variation in consecutive trough levels seen in the oral solution/capsule comparison. This study shows that cyclosporin capsules can be substituted for oral solution without causing acute changes in cyclosporin blood levels, and that the pharmacokinetics of the two formulations are similar.This work was carried out in partial fulfillment of the requirements for the Master of Science Degree in Clinical Pharmacy, University of London 相似文献
94.
本工作观察了乙酰胆硷(Ach)和电刺激迷走神经对0.6N HCl引起的胃粘膜出血性损伤的保护作用,发现皮下注射50μg/kg的氯化Ach和电刺激膈下迷走神经5min,可明显降低HCl引起的胃粘膜出血量,这一作用可被消炎痛及阿托品所阻断。提示这种保护作用是通过依赖于M-受体的内源性前列腺素。 相似文献
95.
本实验用Langendorff法,在恒温、恒液压(灌流压)和供给足够氧气的条件下,对豚鼠(Cavin porcellus)离体心脏进行灌流,以心肌收缩力、心跳频率、心电图和冠脉流量为观察指标,对照观察A型肉毒毒素对心脏活动的影响。结果发现:A型肉毒毒素可使(1)心肌收缩力减弱;(2)心跳频率减慢,甚至停搏;(3)冠脉流量减少;(4)心电图有异常改变,显示对心脏起搏有阻遏现象. 相似文献
96.
Hannie G. A. Bouman Monique L. A. Broekhuizen A. Mieke J. Baasten Adriana C. Gittenberger-De Groot Arnold C. G. Wenink 《Anatomical record (Hoboken, N.J. : 2007)》1995,243(1):101-108
Background: In a recently developed chick model the teratogen retinoic acid has appeared to induce a spectrum of double outlet right ventricle, which needs further detailed evaluation. It is known that retionic acid is able to induce cardiac malformations. Although the exact mechanism is not known, an interaction with neural crest cell function is thought to exist. Methods: After treatment with 1 μg all-trans retinoic acid at Hamburger and Hamilton stage 15 and reincubation until stage 34 of development 41 chicken embryos were evaluated macroscopically and microscopically, supported by graphic reconstructions. These retinoic acid treated embryos were compared with a control group (n = 8). Results: The retinoic acid treated embryos could be divided in three groups. Group 1 (23/41) had an intact septum, group 2 (11/41) had an isolated ventricular septal defect (VSD), and group 3 (7/41) had a double outlet right ventricle (DORV). Besides, in the group with an intact septum 11 hearts showed an abnormal course of the subaortic outflow tract. In the group with DORV a straddling tricuspid orifice (7/8) and a double inlet left ventricle (1/8) could be distinguished. Considering the external contour, the hearts in the DORV group all showed a dextroposed arterial pole. Malformed pharyngeal arch arteries were found in all three groups (11/41) and with a great diversity. Conclusions: The present cardiac malformations in the chicken as a result of retinoic acid treatment are part of a continuous spectrum, varying from hearts with an intact ventricular septum and a normal course of the subaortic outflow tract to a double outlet right ventricle with a straddling tricuspid orifice or even a double inlet left ventricle. A remarkable observation in this spectrum concerns the correlation of malformations of the inflow and outflow tracts, which is explained as a cardiac looping disturbance. The disturbance of the looping process seems to lead to malalignment of septal components, although, in the chick, retinoic acid does not in general interfere with the formation of these septal components themselves. © 1995 Wiley-Liss, Inc. 相似文献
97.
Twenty-four patients treated with 150 mg amitriptyline per day for an episode of major depression underwent a standardized heart rate analysis (HRA) before therapy and after 14 days. The battery of cardiovascular reflex tests included the determination of the coefficient of variation (CV) while resting and during deep respiration, a spectral analysis of heart rate, the heart rate response to standing, and the Valsalva manoeuvre. The results of the initial HRA did not differ from a group of 24 normal control subjects matched for age and sex. On day 14 of treatment the patients showed significantly reduced values of heart rate variability in all tests (P<0.0001), probably due to the anticholinergic side effects of amitriptyline. Heart rate increased form 78.1 to 93.6 bpm on average (P<0.0001). Abnormal CV at rest was registered in 96% of the patients; during deep respiration 29% showed abnormal CV results. An abnormal spectral analysis was found in 100% of the cases (low frequency peak: 42%, mid-frequency peak: 100%, high frequency peak: 79%). The heart rate response to standing was abnormal in 75% and the Valsalva test in 33% of the cases. Eighty-eight percent of the patients fulfilled the criteria of a cardiovascular autonomic neuropathy under the conditions of amitriptyline therapy. As yet, the consequences of these changes for the patients have not been sufficiently elucidated. 相似文献
98.
A survey of 402 normal subjects (203 men, 199 women) was conducted to assist in distinguishing potential differences in norms of hand strength. Norm data had previously been collected from mixed occupational groups, but in the present study it was hypothesised that people involved in heavy manual work on a daily basis might possess greater hand strength than others. The volunteers were adults working in industry and agriculture; they were subdivided into occupational categories. Measurements of grip, key and palmar pinch using the Jamar dynamometer and B and L pinch gauge were collected, using the protocol described by Mathiowetz. Volunteers also rated their individual hand strength job requirements subjectively. Mean values were established with regard to age, sex, dominance, occupational group and subjective rating. Significant differences were found with regard to age and sex but not to dominance; there was no evidence of differences between occupational groups or between subjective rating and individual scoring, i.e. volunteers who perceived their job as requiring a high degree of strength did not achieve higher test measurements than others. A high interrater reliability was demonstrated when comparing these follow-up measurements with the original data. It was concluded that, for clinical and rehabilitative purposes, therapists can interpret assessment of outcome most accurately by comparing patients' results with the existing norm data. 相似文献
99.
化工行业职业性机械伤害危险因素的病例-交叉方法研究 总被引:6,自引:0,他引:6
目的 研究化工行业机械伤害的有关诱发因素,估计其作用强度。方法 采用病例-交叉设计的方法。以操作和检修时受伤的化工工人为研究对象,每个对象在受伤后2d内完成调查,收集他们受伤前10min、上一工作日同一段时间和受伤前1周内有关诱发因素暴露的信息,用配对时间段方法和一般频数法进行分析,评估各种诱发因素的危险度。结果 一般频数法分析的结构表明,操作方法异常、设备工具缺陷、工作紧迫、注意力不集中、不使用防护用品、精神状况较差、与同事配合不协调、工作环境发生变化等瞬时危害因素的RR值及95%可信限的下限均大于1。配对时间段方法分析的结果与其相拟,但95%可信限较宽。结论 化工行业职业性机械伤害的发生存在着诸多诱发因素。病例-交叉研究中的一般频数法与配对时间段方法相比,前者所得结果较为可靠,研究的相对效率较高。建议进一步使用多个时间段方法进行研究,以减小混杂因素的影响。 相似文献
100.
Treatment of rat heart grafts with PUVA, the combination of the photosensitizer 8-methoxypsoralen and longwave ultraviolet light, leads to a prolonged transplant survival in allogeneic recipients. A PUVA treatment of the recipient rats, performed for 7 consecutive days after transplantation, prolonged graft survival even more effectively. This may be due to the systemic immunomodulatory effects of PUVA in the recipient. One of the mediators is urocanic acid, which is transformed by ultraviolet light in the skin from its trans- to the cis-isomer, which, in turn, acts as a mediator on the immune system. An injection of cisurocanic acid into graft recipients for 7 consecutive days after transplantation resulted in prolonged graft survival; in 40% of the rats, permanent graft acceptance was observed. The significance of these results for clinical organ transplantation is discussed. 相似文献