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71.
David P. Faxon David Holmes Geoffrey Hartzler Spencer B. King Gerald Dorros 《Catheterization and cardiovascular interventions》1992,25(1):1-3
At present, the majority of cardiac catheterization laboratories acquire and store hemo-dynamic data in analog form. To examine the possibility of performing complex analysis of digital data during the catheterization procedure, we examined whether virtual realtime digital (fast Fourier) analysis improves the accuracy of clinical data. We compared digital filtering of fluid manometry during right heart catheterization with 10-Hz and 250-Hz analog filters. Using the simultaneously acquired micromanometry as the “gold standard,” we found that analog filtering is associated with a greater error and time delay than digital filtering. This study demonstrates that digital hemodynamic data analysis performed during cardiac catheterization can improve the quality of data obtained during right heart catheterization, with the results available within seconds. More extensive use of computers in the cardiac catheterization laboratory may be useful for both clinical and research purposes. © 1992 Wiley-Liss, Inc. 相似文献
72.
To find out if patients with contact allergy are helped by computerized information lists, a retrospective study was carried out on 58 patients with contact allergy to lanolin, traced through our local database DALUK. All were sent a questionnaire about their usage of the information list, clearance of their eczema, their education and other details. Clearance of the patient's eczema was found to correlate with use of the information list. It was also found that the effectiveness of the information depended on factors such as education, family circumstances, ethnic background and, most of all, how and where the information list was used. 相似文献
73.
Filiation, or a person's parentage, is one of the major componentsof someone's identity, often with important implications forthat person's welfare in social and personal terms. Fertilityspecialists are enjoined to consider the welfare of the child,and this is a legal requirement in assisted reproduction techniquesin the UK. This paper is in three parts, discussing some ofthe potential problems regarding filiation of the prospectivechild born of assisted reproduction techniques, in relationto the use of gametes and embryos. The first two parts concentrateon the status of children born as a result of treatment givenposthumously, and on filiation problems associated with donationof gametes or embryos, and surrogacy. The third part comparesBritish and French legislation with special regard to the welfareof the child, as well as underlining the common trends and principlesenunciated in both legislations. This is particularly appropriateat a time when the European Society for Human Reproduction andEmbryology is about to issue ethical guidelines in assistedreproduction, and when both the Council of Europe and the EuropeanCommission have commissioned studies on the implications ofthe assisted techniques, including those concerning status ofthe potential children. 相似文献
74.
人眼调制传递函数自动测试装置 总被引:1,自引:0,他引:1
本文介绍一个用单片机控制的人眼视网膜-大脑系统调制传递函数测量装置,与传统方法不同,该装置调制对比度是利用电光晶体控制激光束强度的来达到的。该装置不但可以测量空间调制传递的函数,还可测量时-空调制传递函数,并以数据和曲线的形式打印输出。 相似文献
75.
76.
F. Benfenati L. F. Agnati K. Fuxe 《Journal of neural transmission (Vienna, Austria : 1996)》1988,71(2):143-158
Summary Experimentally induced changes in neurotransmitter receptors have been analyzed by means of a computer assisted simulation procedure over a wide range of free ligand concentrations. This approach allows to evaluate, for a given range of ligand concentrations, the relative influence of simultaneous variations in binding parameters (i.e. dissociation constant or Kd and in maximal number of binding sites or Bm) and to predict the net and final effect of the experimental condition on the receptor-mediated transmission line. The function representing the changes in bound values versus the respective free ligand concentrations, has been studied analytically on the basis of all the possible values that the percent changes in both Kd and Bm parameters induced by a given experimental condition can assume. A well characterized change in the pattern of bound radioligand could in this way be defined. This approach, developed to show in an immediate and clear way treatment-induce changes in receptor populations or to fit directly rough experimental data expressed as differences in bound values versus free ligand concentrations, seems to be an useful complement to the widely used saturation analysis of binding data. 相似文献
77.
78.
目的:探讨颅脑外伤严重程度及CT征象与预后的关系,并探讨CT复查的最佳时间及临床意义。方法:回顾性分析80例颅脑外伤的严重程度与初次CT征象的关系,统计分析复查CT发现新病变的数目、程度及时间。结果:颅脑外伤的严重程度与初次CT征象符合率为92.5%(74/80)。外伤后即刻昏迷、CT显示重度复合伤、脑干损伤或弥漫性脑白质损伤的病死率达70.0%(21/30)。1~3d复查CT发现迟发性病变80个,4—7d21个,7d后8个。结论:临床病情与CT征象变化对判断预后有重要意义,颅脑外伤后3、7d是复查CT的最佳时机,出现病情变化应随时复查。 相似文献
79.
在辅助生殖助孕中通常采用控制性卵巢刺激(controlled ovarian hyperstimulation, COS),以获得适当数量的卵子用于体外受精,既希望获得理想的辅助生殖助孕成功率,又能降低卵巢过度刺激并发症.COS中约有9%~24%[1,2]的卵巢低反应发生率.卵巢低反应者获得有效卵子数少、可移植胚胎数少或无胚胎移植、取消治疗周期率高,累计成功率更低等,导致较差的治疗结局,是辅助生殖助孕中面临的棘手问题.针对卵巢低反应者,大多数辅助生殖中心仍会采用增加促性腺激素(Gn)的起始和(或)总用量以期获得提高助孕结局的目的.而大剂量Gn是否为改善低反应患者助孕结局的有效策略却仍存在争议. 相似文献
80.
电视硬质气管镜治疗大气道良性肿瘤 总被引:4,自引:4,他引:0
目的探讨电视硬质气管镜在大气道良性肿瘤治疗中的价值.方法2002年9月~2005年4月,我院应用电视硬质气管镜治疗大气道良性肿瘤7例,其中气管1例,隆突1例,左主支气管3例,右主支气管2例.手术采用静脉全身麻醉,喷射通气供氧,探查评估气道后,首先冷冻或电凝肿瘤,破坏肿瘤血供,再以活检钳分块取出,蒂部采用冷冻或氩气凝固处理;对于宽蒂肿瘤,内镜下将肿瘤主体清除后中转开胸行气管局部切除吻合术.结果7例手术均顺利,无一例死亡和严重并发症发生.6例气管窄蒂良性肿瘤镜下完整摘除,1例气管膜部宽蒂平滑肌瘤先内镜清除肿瘤主体后中转开胸行气管局部切除.术后病理为错构瘤2例,平滑肌瘤3例,嗜酸性肉芽肿性腺瘤1例,炎症组织1例.7例随访3~36个月,平均17.3月,无肿瘤复发.结论电视硬质气管镜治疗大气道良性肿瘤安全可靠. 相似文献