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141.
142.
Cardiac transplantation in perspective for the future. Survival, complications, rehabilitation, and cost 总被引:1,自引:0,他引:1
JL Pennock PE Oyer BA Reitz SW Jamieson CP Bieber J Wallwork EB Stinson NE Shumway 《Canadian Metallurgical Quarterly》1982,83(2):168-177
Two hundred twenty-seven cardiac transplant procedures have been performed in 206 patients from January, 1968, to April, 1981. Postoperative survival rates, calculated by the actuarial method for program years 1968 to 1973 (66 patients), are 44%, 33%, 27%, 21%, and 18% at 1, 2, 3, 4, and 5 years after transplantation, respectively. Postoperative survival rates for program years 1974 to 1981 (140 patients) are 63%, 55%, 51, 44%, and 39% at 1, 2, 3, 4, and 5 years after transplantation, respectively. This increase results primarily from improvement in survival achieved in the first 3 postoperative months (59% +/- 7%, 1968 to 1973, versus 80% +/- 40%, 1974 to 1980), reflecting improved patient management. Infection remains the primary cause of death following transplantation (76/131 patients, 58%), followed by acute rejection (24/181, 18.3%), graft arteriosclerosis (14/131, 10.7%), and malignancy (6/131, 4.6%). The development of graft arteriosclerosis has been examined in 85 one-year survivors studied by annual coronary arteriograms. Coronary lesions of varying severity have developed in 21 patients. HLA-A2 incompatibility was associated with a higher incidence of graft arteriosclerosis than was apparent for all other A locus incompatibilities (p less than 0.0003). Lymphoma has been shown to be associated with younger recipient age, a primary disease diagnosis of idiopathic cardiomyopathy, and retransplantation. One hundred six patients have survived at least 1 year after transplantation; 97% were in NYHA Class 1 at that time interval and 82% returned to employment or activity of choice. The longest survival time is new 11 years, 3 months. Cardiac transplantation can be considered "reasonable and therapeutic treatment to extend life" in selected individuals. 相似文献
143.
本文对铸造C12A高强耐热钢进行了组织与性能、可焊性、焊缝组织变化厦性能特点等方面进行了研究分析。试验结果表明:淬火组织为板务马氏体+部分针状马氏体+少量残余奥氏体,其硬度比较高,塑性和韧性不是很好;淬火+回火组织为保留马氏体形态的回火索氏体,其硬度不是很高,塑性和韧性比较好,具有盘好的综合性能;退火组织为铁素体,其硬度低,塑性和韧性高;焊接后的全相组织中,没有焊接裂纹等焊接缺陷存在,具有良好可焊性。对于淬火+回火后的铸造C12A耐热钢,经过焊接,基体组织和性能没有明显发生变化,过渡区的金相组织为板条马氏体+奥氏体组织,其硬度有所降低;熔化区的金相组织为针状马氏体+奥氏体+板条马氏体,硬度很高;焊后经过回火处理的基体佥相组织与性能没有变化。过度区的金相组织为保留板条马氏体形态的回火索氏体组织,较基体组织要粗大,其硬度要比基体有所下降;熔化区的金相组织转变为保留板每马氏体的回火索氏体,但组织较为基体组织要细小,其性能表现为硬度要比基体的有所升高。铸造C12A焊接后再经回火处理,可使焊接后的组织差别消除;性能变化趋于平缓,有利于材料的使用。 相似文献
144.
Electron acoustic solitons in collisionless and weakly relativistic plasmas are studied. The Krylov–Bogoliubov–Mitropolsky perturbative technique is employed to obtain the nonlinear Schrodinger wave equation. We have numerically investigated modulational instability for different values of the streaming velocity. Graphs have been plotted to see the change in amplitude and inverse width by varying different plasma parameters. 相似文献
145.
Smith P. Shah M. da Vitoria Lobo N. 《Intelligent Transportation Systems, IEEE Transactions on》2003,4(4):205-218
This paper presents a system for analyzing human driver visual attention. The system relies on estimation of global motion and color statistics to robustly track a person's head and facial features. The system is fully automatic, it can initialize automatically, and reinitialize when necessary. The system classifies rotation in all viewing directions, detects eye/mouth occlusion, detects eye blinking and eye closure, and recovers the three dimensional gaze of the eyes. In addition, the system is able to track both through occlusion due to eye blinking, and eye closure, large mouth movement, and also through occlusion due to rotation. Even when the face is fully occluded due to rotation, the system does not break down. Further the system is able to track through yawning, which is a large local mouth motion. Finally, results are presented, and future work on how this system can be used for more advanced driver visual attention monitoring is discussed. 相似文献
146.
147.
Partner Relationship Management (PRM) is an information strategy that employs a set of applications focused on directly impacting an enterprise and its business partners' sales and services. Web services employ a distributed computing architecture that consists of many different computers that communicate over the Internet to form one system. the communication standards and protocols used in Web services are universally accepted. These Web services can be requested by client applications: Web based, windows, or mobile devices. This article presents an overview of PRM and Web services, and discusses the potential for improving partner relationship processes through the use of Web services. 相似文献
148.
This paper presents an efficient image-based approach to navigate a scene based on only three wide-baseline uncalibrated images without the explicit use of a 3D model. After automatically recovering corresponding points between each pair of images, an accurate trifocal plane is extracted from the trifocal tensor of these three images. Next, based on a small number of feature marks using a friendly GUI, the correct dense disparity maps are obtained by using our trinocular-stereo algorithm. Employing the barycentric warping scheme with the computed disparity, we can generate an arbitrary novel view within a triangle spanned by three camera centers. Furthermore, after self-calibration of the cameras, 3D objects can be correctly augmented into the virtual environment synthesized by the tri-view morphing algorithm. Three applications of the tri-view morphing algorithm are demonstrated. The first one is 4D video synthesis, which can be used to fill in the gap between a few sparsely located video cameras to synthetically generate a video from a virtual moving camera. This synthetic camera can be used to view the dynamic scene from a novel view instead of the original static camera views. The second application is multiple view morphing, where we can seamlessly fly through the scene over a 2D space constructed by more than three cameras. The last one is dynamic scene synthesis using three still images, where several rigid objects may move in any orientation or direction. After segmenting three reference frames into several layers, the novel views in the dynamic scene can be generated by applying our algorithm. Finally, the experiments are presented to illustrate that a series of photo-realistic virtual views can be generated to fly through a virtual environment covered by several static cameras. 相似文献
149.
150.
Rahaman Md. Saifur Hasnine Shah Md. Marzuk Ahmed Tanvir Sultana Salma Bhuiyan Md. Abdul Quaiyum Manir Md. Serajum Ullah Nayeb Sen Sapan Kumar Hossain Md. Nazmul Hossain Md. Sahadat Dafader Nirmal Chandra 《Iranian Polymer Journal》2021,30(10):1101-1116
Iranian Polymer Journal - Hydrogels were produced from mixtures of polyvinyl alcohol (PVA), polyvinyl pyrrolidone (PVP), and acrylic acid (AAc) using γ-radiation at doses of 3, 7, and... 相似文献