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The purpose of this study was to provide, in a large number of patients, comprehensive Doppler echocardiographic assessment of normal St Jude Medical mitral valve prosthesis function using Doppler-derived hemodynamic variables, including the mitral valve prosthesis-to-left ventricular outflow tract time-velocity integral ratio and prosthesis performance index. The pressure half-time was less than 130 milliseconds in all patients, and all but one patient had either a peak early mitral diastolic velocity of 2 m/s or less or a mitral valve prosthesis-to-left ventricular outflow tract time-velocity integral ratio of less than 2.2. There was a significant (P < .001) negative correlation between the prosthesis performance index and prosthesis size. This negative correlation suggests that there is more efficient use of the in vitro geometric orifice area with smaller prostheses.  相似文献   
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Jay P. Brooks 《Transfusion》2005,45(S4):159S-171S
Efforts to make blood transfusion as safe as possible have focused on making the blood in the bag as disease-free as possible. The results have been dramatic, and the costs have been correspondingly high. Although blood services will have to continue to deal with emerging pathogens, efforts to reduce the transfusion of infectious agents presently posing a risk will require high incremental costs and result in only improvements of a small magnitude.
The other aspect of safe blood transfusion, the actual transfusion process performed primarily in hospitals, has been accorded considerably less interest. We should turn our attention to enhancing overall blood safety by focusing on improving the process of blood transfusion. Errors involving patient, specimen, and blood product identification put transfused patients at risk, increasing the mortality risk for some. Solutions that could improve the transfusion process are discussed as a focus of this article.  相似文献   
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PURPOSE: Bevacizumab, a monoclonal antibody against vascular endothelial growth factor, increases survival when combined with irinotecan-based chemotherapy in first-line treatment of metastatic colorectal cancer (CRC). This randomized, phase II trial compared bevacizumab plus fluorouracil and leucovorin (FU/LV) versus placebo plus FU/LV as first-line therapy in patients considered nonoptimal candidates for first-line irinotecan. PATIENTS AND METHODS: Patients had metastatic CRC and one of the following characteristics: age > or = 65 years, Eastern Cooperative Oncology Group performance status 1 or 2, serum albumin < or = 3.5 g/dL, or prior abdominal/pelvic radiotherapy. Patients were randomly assigned to FU/LV/placebo (n = 105) or FU/LV/bevacizumab (n = 104). The primary end point was overall survival. Secondary end points were progression-free survival, response rate, response duration, and quality of life. Safety was also assessed. RESULTS: Median survival was 16.6 months for the FU/LV/bevacizumab group and 12.9 months for the FU/LV/placebo group (hazard ratio, 0.79; P = .16). Median progression-free survival was 9.2 months (FU/LV/bevacizumab) and 5.5 months (FU/LV/placebo); hazard ratio was 0.50; P = .0002. Response rates were 26.0% (FU/LV/bevacizumab) and 15.2% (FU/LV/placebo) (P = .055); duration of response was 9.2 months (FU/LV/bevacizumab) and 6.8 months (FU/LV/placebo); hazard ratio was 0.42; P = .088. Grade 3 hypertension was more common with bevacizumab treatment (16% v 3%) but was controlled with oral medication and did not cause study drug discontinuation. CONCLUSION: Addition of bevacizumab to FU/LV as first-line therapy in CRC patients who were not considered optimal candidates for first-line irinotecan treatment provided clinically significant patient benefit, including statistically significant improvement in progression-free survival.  相似文献   
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Zusammenfassung Die Kausalgie ist eine Erkrankung mit vorwiegender Beteiligung des sympathischen Nervensystems, die h?ufig im Anschlu\ an Teill?sionen des N. medianus und tibialis auftritt. Denn nur zu diesen beiden Nerven führen auch marklose sympathische Fasern in gr?\erer Zahl. Die Erkrankung wird — wie an den genau beobachteten 3 F?llen festgestellt wurde — nicht oder erst sehr sp?t erkannt, obwohl die typischen Erscheinungen (starker Handschwei\, hochgradiges Schmerzgefühl mit dem Ausdruck brennender Hitze) schon bald nach der Verletzung (4-6-13 Wochen) auftreten. Dieses Nichterkennen geht soweit, da\ die davon Betroffenen als Hysteriker und Psychopathen angesehen werden. Durch Entfernen des Ganglion stellatum und aller Verbindungen, die zum Armnervengeflecht führen, ist eine vollkommene Heilung zu erzielen. Wenn die benachbarten Ganglien und ihre Anastomosen zum Plexus nicht entfernt werden (s. Fall 3) bleiben geringe, leicht ertr?gliche Beschwerden zurück. Nach der Operation tritt vollst?ndige Schmerzfreiheit und derHornersche Symptomkomplex auf. Klinische Erscheinungen wie Schwindel gehen nach wenigen Tagen zurück. Bemerkenswert ist noch die Tatsache, da\ in einem Fall die kausalgischen Reizerscheinungen an beiden Armen vorhanden waren (Schu\verletzung beider mediani) und durch die Operation an der st?rker betroffenen rechten Seite die Krankheitserscheinungen beiderseits geschwunden sind. Geringe histologische Ver?nderungen an den entfernten Ganglien sind vorgefunden worden. Herrn Prof.Feyrter, Vorstand des Pathologisch-anatomischen Institutes der Universit?t Graz, sei in diesem Zusammenhang für die Untersuchung und überlassung der histologischen Pr?parate bestens gedankt.   相似文献   
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BackgroundHuman studies on exercise, cognition, and apolipoprotein E (APOE) genotype show that ε4 carriers may benefit from regular physical activity.MethodsWe examined voluntary wheel-running, memory, and hippocampal plasticity in APOE ε3 and APOE ε4 transgenic mice at 10–12 months of age.ResultsSedentary ε4 mice exhibited deficits in cognition on the radial-arm water maze (RAWM), a task dependent on the hippocampus. Six weeks of wheel-running in ε4 mice resulted in improvements on the RAWM to the level of ε3 mice. Hippocampal brain-derived neurotrophic factor (BDNF) levels were similar in ε3 and ε4 mice, and after exercise BDNF was similarly increased in both ε3 and ε4 mice. In sedentary ε4 mice, tyrosine kinase B (Trk B) receptors were reduced by 50%. Exercise restored Trk B in ε4 mice to the level of ε3 mice, and in ε4 mice, exercise dramatically increased synaptophysin, a marker of synaptic function.ConclusionsOur results support the hypothesis that exercise can improve cognitive function, particularly in ε4 carriers.  相似文献   
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