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51.
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Between September 1979 and December 1982, 56 St Jude Medical valvular prostheses were implanted in 54 patients over 65 years of age. Surgery consisted in simple aortic valve replacement (35 cases), simple mitral valve replacement (12 cases), double aortic and mitral valve replacement (2 cases), valve replacement and coronary artery bypass surgery (3 cases), aortic valve replacement and replacement of the ascending aorta (1 case) and mitral valve replacement and tricuspid annuloplasty (1 case). The operative mortality (within 30 days of surgery) was 3.5% (2 cases). Patients were assessed by clinical examination, ECG, chest X-ray, echocardiogram and laboratory investigations on average 19 months after surgery. There were 3 late deaths (1 endocarditis, 1 cardiac failure and 1 subdural haematoma). No cases of significant haemolysis were observed. There were no cases of thrombosis of the valve or any deaths directly related to the valve. Four patients had cerebral embolism (4.9% per patient/year). None were fatal and only 1 patient had sequellae. Clinical improvement was very significant; 96% of the patients are now in the NYHA Classes I and II whilst 80% were in Class III or IV before surgery. The cardiothoracic ratio decreased significantly from 0.56 to 0.51 (p less than 0.01). The authors conclude that elderly patients may derive great benefits from valvular cardiac surgery and that age in itself is not a contraindication to this type of surgery. The St Jude Medical prosthesis is an excellent prosthesis but thromboembolism remains a major problem as with other mechanical prostheses. Anticoagulation for life is essential.  相似文献   
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OBJECTIVES: Little is known about the physiologic and clinical effects of noninvasive positive pressure ventilation (NPPV) in patients who have acute respiratory failure (ARF) after abdominal surgery. We evaluated our clinical experience with the use of NPPV in the treatment of ARF after abdominal surgery. METHODS: We prospectively evaluated NPPV use during a 2-year period in a medical-surgical ICU of a university hospital. We documented demographic and diagnostic data, gas exchange, and clinical outcomes. We compared patients who were not intubated to those who were intubated after a trial of NPPV. RESULTS: Of 72 patients with ARF after abdominal surgery who were treated with NPPV, 48 patients avoided intubation (67%). Patients in the intubated and nonintubated groups had similar demographic characteristics, and similar American Society of Anesthesiologists physical status and simplified acute physiology score II scores at admission. The intubated group had a significantly lower Pa(O2)/fraction of inspired oxygen (Fi(O2)) ratio (123 +/- 62 mm Hg vs 194 +/- 76 mm Hg, p < 0.01) and more extended bilateral alveolar infiltrates (67% vs 31%, p < 0.01) than the non-intubated group. Within the first NPPV observation period, the Pa(O2)/Fi(O2) increased (+ 36 +/- 29% [+/- SD], p = 0.04) and the respiratory rate decreased (28.2 +/- 3.4 breaths/min vs 23.1 +/- 3.8 breaths/min, p < 0.01) significantly only in the non-intubated group. The non-intubated group had significantly lower length of ICU stay (17.3 +/- 10.9 days vs 34.1 +/- 28.5 days, p < 0.01) and mortality rate (6% vs 29%, p < 0.01). CONCLUSION: NPPV may be an alternative to conventional ventilation in selected patients with ARF after abdominal surgery who require ventilatory support.  相似文献   
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STUDY OBJECTIVES: Although agitation is thought to be common in the ICU, it has been poorly studied. We evaluated the incidence, risks factors, and outcomes of agitation in ICU. DESIGN: Prospective observational study. INTERVENTIONS: None. METHOD: All consecutive ICU admissions over an 8-month period were analyzed. MEASUREMENTS AND RESULTS: Two hundred eleven patients were admitted a total of 216 times during the period of the study. Twenty-nine patients were excluded from the study because their pathology findings did not allow an evaluation of their level of consciousness; 182 patients were actually enrolled. Agitation developed in 95 of 182 patients (52%). Agitation began 4.4 +/- 5.6 days (+/- SD) after admission to the ICU and lasted 3.9 +/- 4.1 days. Patients with agitation had a higher Simplified Acute Physiology Score II on ICU admission than those who did not have agitation (40 +/- 16 vs 33 +/- 13, p < 0.01). By stepwise logistic regression, the independent risks factors for development of agitation included psychoactive drug use at the time of ICU admission (odds ratio, 5.63; 95% confidence interval [CI], 1.32 to 23.70), history of alcohol abuse (odds ratio, 3.32; 95% CI, 1.12 to 10.00), dysnatremia (odds ratio, 4.95; 95% CI, 1.95 to 12.54), fever (odds ratio, 4.52; 95% CI, 1.80 to 11.49), use of sedatives in the ICU (odds ratio, 4.03; 95% CI, 1.62 to 10.40), and sepsis (odds ratio, 2.61; 95% CI, 1.03 to 6.58). Agitation was associated with a prolonged ICU stay (16 +/- 19 days vs 6 +/- 6 days, p = 0.0001), nosocomial infections (34% vs 7%, p < 0.0001), unplanned extubations (17% vs 2%, p = 0.003), and unplanned central venous catheter removal (16% vs 1%, p = 0.001), but not with mortality (12% in the agitation group vs 8% in patients without agitation). CONCLUSIONS: Agitation is a common event in a mixed medical-surgical ICU. It is associated with adverse outcomes including prolonged stay, nosocomial infections, and unplanned extubations. A better knowledge of incidence and risk factors should facilitate identification of patients at risk and decrease the incidence of agitation.  相似文献   
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The transition from the Middle Paleolithic (MP) to Upper Paleolithic (UP) is marked by the replacement of late Neandertals by modern humans in Europe between 50,000 and 40,000 y ago. Châtelperronian (CP) artifact assemblages found in central France and northern Spain date to this time period. So far, it is the only such assemblage type that has yielded Neandertal remains directly associated with UP style artifacts. CP assemblages also include body ornaments, otherwise virtually unknown in the Neandertal world. However, it has been argued that instead of the CP being manufactured by Neandertals, site formation processes and layer admixture resulted in the chance association of Neanderthal remains, CP assemblages, and body ornaments. Here, we report a series of accelerator mass spectrometry radiocarbon dates on ultrafiltered bone collagen extracted from 40 well-preserved bone fragments from the late Mousterian, CP, and Protoaurignacian layers at the Grotte du Renne site (at Arcy-sur-Cure, France). Our radiocarbon results are inconsistent with the admixture hypothesis. Further, we report a direct date on the Neandertal CP skeleton from Saint-Césaire (France). This date corroborates the assignment of CP assemblages to the latest Neandertals of western Europe. Importantly, our results establish that the production of body ornaments in the CP postdates the arrival of modern humans in neighboring regions of Europe. This new behavior could therefore have been the result of cultural diffusion from modern to Neandertal groups.  相似文献   
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Essential thrombocythemia, a myeloproliferative neoplasm, is associated with increased platelet count and risk of thrombosis or hemorrhage. Cytoreductive therapy aims to normalize platelet counts despite there being only a minimal association between platelet count and complication rates. Evidence is increasing for a correlation between WBC count and thrombosis, but prospective data are lacking. In the present study, we investigated the relationship between vascular complications and 21 887 longitudinal blood counts in a prospective, multicenter cohort of 776 essential thrombocythemia patients. After correction for confounding variables, no association was seen between blood counts at diagnosis and future complications. However, platelet count outside of the normal range during follow-up was associated with an immediate risk of major hemorrhage (P = .0005) but not thrombosis (P = .7). Elevated WBC count during follow-up was correlated with thrombosis (P = .05) and major hemorrhage (P = .01). These data imply that the aim of cytoreduction in essential thrombocythemia should be to keep the platelet count, and arguably the WBC count, within the normal range. This study is registered at the International Standard Randomized Controlled Trials Number Registry (www.isrctn.org) as number 72251782.  相似文献   
59.
Immediately after the annual scientific meeting of the American Society of Hematology (ASH), a select group of clinical and laboratory investigators in myeloproliferative neoplasms (MPN) is summoned to a post-ASH conference on chronic myeloid leukemia and the BCR-ABL1-negative MPN. The 6th such meeting occurred on December 13–14,2011, in La Jolla, California, USA, under the direction of its founder,Dr. Tariq Mughal. The current document is the first of two reports on this post-ASH event and summarizes the most recent preclinical and clinical advances in polycythemia vera, essential thrombocythemia,and primary myelofibrosis.  相似文献   
60.
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