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991.
992.
Hydrogen peroxide release by alveolar macrophages from sarcoid patients and by alveolar macrophages from normals after exposure to recombinant interferons alpha A, beta, and gamma and 1,25-dihydroxyvitamin D3. 总被引:5,自引:2,他引:5
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We measured H2O2 release by human alveolar macrophages (AM) from normals and sarcoid patients in suspension immediately after bronchoalveolar lavage in the presence and absence of the triggering agent, phorbol myristate acetate (PMA). AM from 11 sarcoid patients produced a mean (+/- SE) of 21.7 +/- 2.3 and 5.9 +/- 3.4 nmol H2O2/10(6) macrophages in the presence and absence of PMA, respectively. By contrast, AM from normals (n = 6) produced 9.8 +/- 1.7 and 1.6 +/- 0.7 nmol H2O2/10(6) macrophages with and without PMA, respectively. Macrophage activation, as monitored by H2O2 production, did not correlate with the angiotensin-converting enzyme levels, the result of gallium-67 scans, or the percent of lymphocytes in the bronchoalveolar lavage. To determine whether AM from normals could be stimulated to increase their H2O2 production to the level seen in patients with sarcoid, we measured H2O2 released by adherent AM after incubation in each of four potential activating agents: recombinant interferons alpha A, beta, gamma (rIFN alpha A, rIFN beta, and rIFN gamma, respectively), and 1,25-dihydroxyvitamin D3. H2O2 release in the range seen in sarcoid patients could be induced in PMA-triggered AM from normals by rIFN gamma in a time- (t1/2 approximately 1 d) and dose-dependent fashion (threefold increase, EC50 5 antiviral U/ml) and by rIFN alpha A and rIFN beta at higher concentrations, but not by 1,25-dihydroxyvitamin D3. 相似文献
993.
R S Bexton K J Hellestrand A W Nathan S O Banim A J Camm 《Pacing and clinical electrophysiology : PACE》1983,6(6):1273-1277
A case is reported of a patient with functional duality of AV nodal conduction in whom, during ventricular extrastimulus testing, there was a gap in retrograde fast pathway conduction which allowed the temporary expression of retrograde slow pathway conduction. The administration of the antiarrhythmic agent flecainide, which has disparate effects on retrograde fast and slow pathway conduction characteristics, accentuated this phenomenon. The electrophysiological basis of gap phenomena is discussed. 相似文献
994.
John McManus MD MCR Nathan D. Magaret MD Jerris R. Hedges MS MD Nicolas B. Rayner BA Matthew Rice JD MD 《Academic emergency medicine》2005,12(9):896-899
Objectives: To assess emergency physician reporting patterns in Oregon before and after the passage of a mandatory intoxicated driving reporting law. Methods: A one‐page survey was mailed to 504 emergency physicians in Oregon in April 2004. Data on reporting frequency were collected using a four‐point ordinal scale regarding motor vehicle crash–involved drivers (MIDs) and intoxicated persons attempting to drive away from the emergency department (DAEDs). Paired observations were assessed for a stated increase in reporting activity following passage of the law using the Wilcoxon signed‐rank test. Associations of postlaw reporting and demographic and knowledge factors were sought using Spearman rank correlation analysis. Results: Of the 504 surveys mailed, 298 (59%) were adequate for analysis. Many respondents (57%) were already aware of the law. Most (92%) agreed that physicians should be mandated to report some crimes. MIDs were always reported by 18% of physicians before the law and by 47% afterward, whereas DAEDs were always reported by 56% of physicians before the law and by 69% afterward. Emergency medicine–trained physicians, higher emergency department census, and increased years of experience were associated with a significantly higher increase in reporting pattern after passage of the law for both MIDs and DAEDs. Conclusions: Although 44% of responding emergency physicians in Oregon were unaware of a mandated reporting law for intoxicated drivers presenting to the ED, most physicians stated an increase in their reporting practice. 相似文献
995.
Mesenteric vein thrombosis is an uncommon manifestation of hypercoagulable states. A case is reported of superior mesenteric vein (SMV) thrombosis in a patient with pancreatitis and protein C deficiency. A discussion of SMV thrombosis identification, management, and outcomes is included. The patient presented with a significant history of alcohol abuse and constant, midepigastric abdominal pain associated with nausea and vomiting. Amylase and lipase were elevated, and the patient was treated for pancreatitis. His symptoms initially responded to intravenous fluid hydration, but soon his clinical picture worsened, with increased nausea and vomiting, abdominal pain, and distension. Contrasted computed tomography of the abdomen revealed SMV thrombosis. A hypercoagulable workup revealed protein C deficiency. After a 3-month course of oral anticoagulant therapy, the SMV thrombosis resolved. 相似文献
996.
Nathan L. Pace Theodore H. Stanley Kirk P. Andriano Johan Wilbrink Prisca Zwanikken 《Journal of clinical monitoring and computing》1985,1(4):227-232
We compared values of PaO2 and transcutaneous PO2 in 21 adult patients during anesthesia. In 282 simultaneous determinations during anesthetic periods of 3–10 h, transcutaneous PO2 was a poor predictor of absolute PaO2 and changes in PaO2. Trancutaneous PO2 monitoring in adults during anesthesia is of unproven value. 相似文献
997.
998.
999.
Mohamed A. Kharfan-Dabaja Renju Raj Liana Nikolaenko Sairah Ahmed Nishitha Reddy Sunita Nathan Mohamad Cherry Najla El-Jurdi Cynthia Obiozor Timothy S. Fenske Joo Song Tariq Muzzafar Ernesto Ayala Bipin Savani Mohamad Khawandanah Paolo F. Caimi Mehdi Hamadani Stephen J. Forman Siddhartha Ganguly 《Biology of blood and marrow transplantation》2018,24(3):486-493
High-dose therapy (HDT) and autologous hematopoietic cell transplantation (auto-HCT) has been anecdotally prescribed in gray zone lymphoma (GZL), showing encouraging efficacy. We conducted a multicenter retrospective study aimed at assessing outcomes after auto-HCT in 32 patients with GZL treated at 9 transplantation centers in the United States. The median age of patients at transplantation was 38 years (range, 18 to 70 years), and the majority were male (n?=?21; 66%). The median number of lines of therapy before transplantation was 2 (range, 1 to 4). BEAM was the most commonly prescribed regimen (n?=?23; 72%). The median duration of follow-up for surviving patients was 34 months (range, 1 to 106 months). Median overall survival (OS) was not reached. The 3-year progression-free survival (PFS) and OS for all patients were 69% and 78%, respectively. Three-year PFS and OS were 100% for patients who received only 1 line of therapy before auto-HCT versus 65% (PFS, P?=?.25) and 75% (OS, P?=?.39) for those receiving >1 line. The cumulative incidence of relapse/progression was 4% at 1 year post-transplantation and 31% at 3 years post-transplantation. The 3-year nonrelapse mortality was 0%. These findings suggest that HDT and auto-HCT is an effective treatment in patients with GZL. Our findings ideally require confirmation in a larger cohort of patients, preferably in the setting of large prospective multicenter randomized controlled trials. However, we acknowledge that such studies could be difficult to conduct in patients with GZL owing to the disease's rarity. Alternatively, a multicenter prospective study that includes tissue banking and a data registry is warranted to help better understand the biology and natural history of the disease. 相似文献
1000.
Peter S. Dayan MD MSc Michael Vitale MD MPH Daniel J. Langsam BA Carrie Ruzal-Shapiro MD Michael K. Novick BA Nathan Kuppermann MD MPH Steven Z. Miller MD 《Academic emergency medicine》2004,11(7):736-743
OBJECTIVE: The authors sought to derive maximally sensitive prediction rules for identifying children with significant fractures after acute twisting injuries to the ankle. METHODS: The authors prospectively enrolled a convenience sample of patients younger than 18 years of age who presented to the pediatric emergency department of an urban, tertiary care center after sustaining acute twisting injuries of the ankle. The ankle was defined in two regions: the malleolar zone and the midfoot zone. Clinical findings were documented on standardized data collection sheets by faculty physicians before completion of ankle and/or foot radiograph series. Significant fracture was defined a priori as any fracture other than an avulsion < or =3 mm. The authors conducted binary recursive partitioning with cross-validation to develop models to predict fracture. RESULTS: Data from 717 enrolled patients with a median age of 12.9 years were analyzed. Significant malleolar zone and midfoot zone fractures were diagnosed in 81 of 682 (11.9%) and 10 of 173 (5.8%) patients for whom ankle and foot radiographs were obtained. Recursive partitioning identified patients at low risk for malleolar zone fracture if 1) they had no bone tenderness at either malleolus or the region just proximal to the fibula malleolus or 2) they had bone tenderness at either malleolus but were able to walk four steps in the emergency department and had no swelling at either malleolus. The two-part malleolar zone rule had a sensitivity of 100% and specificity of 19.1% on the learning data and 95.1% (95% confidence interval [95% CI] = 87.8% to 98.6%) and 20.0% (95% CI = 16.8% to 23.4%) on the test data. Tenderness either at the proximal fifth metatarsal or cuboid identified midfoot zone fractures with a sensitivity of 100% and specificity of 31.9% on the learning data and 90.0% (95% CI = 55.4% to 99.7%) and 35.0% (95% CI = 27.7% to 42.8%) on the test sample. CONCLUSIONS: A set of sensitive prediction rules was developed to identify children with significant fractures after twisting injuries to the ankle. External validation and refinement of the rules will be needed before recommendation of widespread use. 相似文献