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91.
92.
Since the first implantation in man in 1980 implantable cardioverter defibrillator technology has greatly improved and the number of devices implanted has increased considerably every year. Non thoracotomy lead systems and biphasic shocks are now the approach of choice, offering an almost 100% success rate. This document reviews the recommendations for qualification of personnel and for the centres implanting and carrying out follow-ups on defibrillators. The current indications for the implantation of implantable cardioverter defibrillator are also addressed.  相似文献   
93.
Microencapsulation by means of step-wise adsorption of polyelectrolytes   总被引:2,自引:0,他引:2  
Step-wise adsorption of polyelectrolytes is used for the fabrication of micro- and nanocapsules with determined size, capsule wall composition and thickness. The capsule walls made of polyelectrolyte multilayers exclude high molecular weight compounds. Assembling of lipid layers onto these polyelectrolyte capsules prevents the permeation of small dyes. Encapsulation of magnetite nanoparticles is demonstrated and the features of these novel capsules are discussed.  相似文献   
94.
An antibody that facilitates hematopoietic engraftment recognizes CD44   总被引:1,自引:2,他引:1  
Sandmaier  BM; Storb  R; Appelbaum  FR; Gallatin  WM 《Blood》1990,76(3):630-635
Pretreatment of recipients with the monoclonal antibody (MoAb) S5 facilitates engraftment of bone marrow from mismatched, unrelated donors in the canine transplantation model. In the direct comparisons reported here, the S5 glycoprotein (gp) was found to have structural homology to CD44 that in humans has been implicated in adhesive interactions of one type of effector cell, the lymphocyte. The S5 antigen and gp90Hermes-1 exhibited codistribution on canine peripheral blood cells. Both S5 and Hermes-1 (anti-CD44) MoAbs recognized 90-Kd species in radioimmune precipitations of 125I surface-labeled canine peripheral blood lymphocytes and bone marrow cells. Competitive antibody binding experiments showed that the epitope detected by S5 was distinct from that bound by Hermes-1 but overlapped with those defined by two other known anti-CD44 reagents, IM7 and Hutch-1. Sequential immunoprecipitation with S5 and Hermes-1 indicated that the two antibodies recognize the same or overlapping subsets of membrane gps. Tryptic digestion of S5 and anti-CD44 immunoprecipitates generated two major iodinated peptides of 27 and 35 Kd in both cases, a further indication of structural homology. Similarly, after N-glycanase digestion, S5 and CD44 immunoprecipitates were resolved to a single 68- Kd species. These findings suggest that CD44-mediated adhesive events may affect the fate of transplanted hematopoietic cells. The previous implications of this gp in T-lymphocyte activation and lymphocyte adhesion to endothelium thus provide useful paradigms to analyze its function in the bone marrow transplant setting.  相似文献   
95.
96.
AIMS: To investigate the sensitivity of the rate of pressure rise obtained by Doppler to changes in the inotropic state by comparing it to simultaneous invasive measurements of dP/dt under different conditions of contractility. METHODS AND RESULTS: Mitral regurgitation was provoked in five pigs, and simultaneous measurements of dP/dt and the Doppler-estimated rate of pressure rise were made with a micro-manometer and with continuous-wave Doppler. Changes in the inotropic state were induced by drug infusion and by ischaemia. One hundred and twenty-seven simultaneous measurements were made with a correlation coefficient between the Doppler-estimated rate of pressure rise and dP/dt of 0.85 (P<0.001). Sensitivity to inotropic changes was estimated as the percentage change of each parameter in each condition of contractility, and showed that the Doppler-estimated rate of pressure rise had better sensitivity than dP/dt. CONCLUSION: The sensitivity of Doppler-estimated rate of pressure rise to changes in the inotropic state is greater than that of dP/dt. The correlation between the rate of pressure rise obtained by Doppler and dP/dt is maintained even in extreme conditions of contractility. Therefore, the rate of pressure rise can be considered a good parameter to assess linear changes of contractility.  相似文献   
97.
Ectopic atrial tachycardia is an uncommon cause of supraventricular tachycardia in children. It can resolve spontaneously or induce dilated cardiomyopathy. It is important to recognize this entity as a reversible cause of dilated cardiomyopathy, characterized by the presence of an abnormal focus located in the atrial myocardium and distinct to sinus node. Treatment strategies include the use of antiarrhythmic drugs, radiofrequency ablation, and, in patients refractory to medical treatment, surgical resection of the ectopic focus. We describe a patient with dilated cardiomyopathy due to an atrial ectopic focus and its resolution after medical treatment.  相似文献   
98.
Data from farmer-managed fields have not been used previously to disentangle the impacts of daily minimum and maximum temperatures and solar radiation on rice yields in tropical/subtropical Asia. We used a multiple regression model to analyze data from 227 intensively managed irrigated rice farms in six important rice-producing countries. The farm-level detail, observed over multiple growing seasons, enabled us to construct farm-specific weather variables, control for unobserved factors that either were unique to each farm but did not vary over time or were common to all farms at a given site but varied by season and year, and obtain more precise estimates by including farm- and site-specific economic variables. Temperature and radiation had statistically significant impacts during both the vegetative and ripening phases of the rice plant. Higher minimum temperature reduced yield, whereas higher maximum temperature raised it; radiation impact varied by growth phase. Combined, these effects imply that yield at most sites would have grown more rapidly during the high-yielding season but less rapidly during the low-yielding season if observed temperature and radiation trends at the end of the 20th century had not occurred, with temperature trends being more influential. Looking ahead, they imply a net negative impact on yield from moderate warming in coming decades. Beyond that, the impact would likely become more negative, because prior research indicates that the impact of maximum temperature becomes negative at higher levels. Diurnal temperature variation must be considered when investigating the impacts of climate change on irrigated rice in Asia.  相似文献   
99.
Pancreas and kidney transplantation is the treatment of choice for patients with type 1 diabetes mellitus and terminal renal insufficiency. Herein we have presented a series of 35 patients transplanted between 2002 and 2009 including periods before and after 2007 divided based on introduction of some technical aspects.In the first phase (learning period) we have noted complications related to pancreatic surgery with a morbidity among 12 of 18 patients (66.6%). In the second period (stabilization period), complications appeared in 6 out of 17 patients (35.2%; P < .028). The reoperation rate was 83.3% in the learning period and 23.5% in the stabilization period (P < .03). Seven transplantectomies were performed in the first period (P < .004). Five patients died, all of them in the learning group (P < .019).Changes in the technical aspects of the procedure were responsible for improved outcomes obtained among pancreas and kidney transplantations.  相似文献   
100.
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