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991.
OBJECTIVES: Invasive pulmonary aspergillosis (IPA) is increasingly recognized as a cause of acute respiratory failure in patients with chronic obstructive pulmonary disease (COPD) treated with corticosteroids. For these patients admission in intensive care unit (ICU) is often required for life-support and mechanical ventilation. Whether this approach improves outcome is unknown. DESIGN AND SETTING: Retrospective study in a university hospital intensive care unit. PATIENTS: Between November 1993 and December 1997, 23 COPD patients were admitted in our ICU and received antifungal agents for possible IPA. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: The clinical features and the outcome were reviewed. Diagnosis of IPA was classified as confirmed (positive lung tissue biopsy and/or autopsy) or probable (repeated isolation of Aspergillus from the airways with consistent clinical and radiological findings). Among the 23 patients treated for Aspergillus, 16 fulfilling these criteria for IPA were studied. Steroids had been administered at home to all patients but one and were increased during hospitalization in all. Twelve patients suffered a worsening of their bronchospasm precipitating acute respiratory failure. During ICU stay all patients required mechanical ventilation for acute respiratory failure. Although amphotericin B deoxycholate was started when IPA was suspected (0.5-1.5 mg/kg per day), all patients died in septic shock (n = 5) or in multiple-organ failure. CONCLUSIONS: The poor prognosis of intubated COPD patients with IPA, in spite of antifungal treatment suggests that further studies are required to define the limits and indications for ICU management of these patients.  相似文献   
992.
993.
A gain of function mutation resulting in the substitution of leucine for serine at codon 810 (S810L) in the human mineralocorticoid receptor (MR) is responsible for early-onset hypertension that is exacerbated in pregnancy. All steroids, including progesterone, that display antagonist properties when bound to the wild-type MR are able to activate the mutant receptor (MR(L810)). These findings suggest that progesterone may contribute to the dramatic aggravation of hypertension in MR(L810) carriers during pregnancy. However, the steroid(s) responsible for hypertension in MR(L810) carriers (men and nonpregnant women) has not yet been identified. Here we show that cortisone and 11-dehydrocorticosterone, the main cortisol and corticosterone metabolites produced in the distal nephron, where sodium reabsorption stimulated by aldosterone takes place, bind with high affinity to MR(L810). The potency with which cortisone and 11-dehydrocorticosterone bind to the mutant MR contrasts sharply with their low wild-type MR-binding capacity. In addition, cotransfection assays demonstrate that cortisone and 11-dehydrocorticosterone are potent activators of the MR(L810) trans-activation function. Because the plasma concentration of cortisol in humans is about 30-fold higher than that of corticosterone, these findings strongly suggest that cortisone is one of the endogenous steroids responsible for early-onset hypertension in men and nonpregnant women carrying the MR(L810) mutation.  相似文献   
994.
995.
This paper presents STARS (Simulation and Transfer Architecture for Robotic Surgery), a versatile system that aims at enhancing minimally invasive robotic surgery through patient-dependent optimized planning, realistic simulation, safe supervision, and augmented reality. The underlying architecture of the proposed approach is presented, then each component is detailed. An experimental validation is conducted on a dog for a coronary bypass intervention using the Da Vinci(TM) surgical system focusing on planing, registration, and augmented reality trials.  相似文献   
996.
The purpose of this study was to assess the results of acute grade I and II acromioclavicular (AC) joint sprains treated by conservative measures. Between 1993 and 1997, 37 consecutive patients were treated conservatively for AC joint sprains, grade I and II in the Tossy classification. Of these patients, 4 were excluded (three lost to follow-up and one sustained a further AC injury), leaving a series of 33 patients. Among them, in 9 (27%), chronic AC joint pathology that required subsequent surgery developed at a mean of 26 months after injury. The remaining 24 were reviewed clinically and radiologically at a mean of 6.3 years (range, 4-8 years) after injury. At the latest follow-up, 17 of the 33 patients (52%) remained asymptomatic. Of the 24 patients reviewed, 7 complained of activity-related pain. Eight patients presented with residual anteroposterior instability. Tenderness at the AC joint as well as a positive cross-body test was observed in 12 patients. The mean Constant score at follow-up was 82 points. The x-ray films showed degenerative changes in 13 patients, ossification of the coracoclavicular ligaments in 2, an association of degenerative changes with ossification of the coracoclavicular ligaments in 3, and distal clavicular osteolysis in 3. Only 4 cases had no radiographic changes after this kind of AC injury. On the basis of these results, we conclude that the severity of the consequences after grade I and II AC sprains is underestimated.  相似文献   
997.
998.
Although bone and joint manifestations are common in children with cystic fibrosis (CF), they have received little attention in adults. As compared to healthy individuals, bone mineral density is low, even with calcium intakes greater than 1500 mg/d. Nevertheless, calcium and phosphate levels in blood and urine are often normal, and vitamin D levels vary. Short stature with a low body mass index and central hypogonadism are the rule in these patients. Fractures and kyphosis are often reported. CF arthropathy occurs in 2-8.5% of patients. Arthritis develops, and there may be skin eruptions. Non-steroidal antiinflammatory drug therapy is effective. Hypertrophic osteoarthropathy associated with respiratory failure is present in 2-7% of patients. Rheumatoid arthritis, spondyloarthropathies, sarcoidosis, and amyloidosis have been reported in association with CF. Knee pain due to patellofemoral syndrome, quinolone-induced arthropathy, and mechanical back pain have been described. Rheumatoid factor titers are higher than in healthy controls, particularly in patients with episodic arthritis. No data are available on antiperinuclear factor or antikeratin antibody titers. Tests for antinuclear antibody are usually negative. Circulating immune complex levels and antibodies to heat shock proteins may be elevated. Antineutrophil cytoplasmic antibody of the bactericidal/permeability-increasing protein (BPI) or azurocidin (AZ) type has been reported, often in high titers (up to 40%).  相似文献   
999.
Context  Many physicians believe that the pulmonary artery catheter (PAC) is useful for the diagnosis and treatment of cardiopulmonary disturbances; however, observational studies suggest that its use may be harmful. Objective  To determine the effects on outcome of the early use of a PAC in patients with shock mainly of septic origin, acute respiratory distress syndrome (ARDS), or both. Design, Setting, and Patients  A multicenter randomized controlled study of 676 patients aged 18 years or older who fulfilled the standard criteria for shock, ARDS, or both conducted in 36 intensive care units in France from January 30, 1999, to June 29, 2001. Intervention  Patients were randomly assigned to either receive a PAC (n = 335) or not (n = 341). The treatment was left to the discretion of each individual physician. Main Outcome Measures  The primary end point was mortality at 28 days. The principal secondary end points were day 14 and 90 mortality; day 14 organ system, renal support, and vasoactive agents–free days; hospital, intensive care unit, and mechanical ventilation–free days at day 28. Results  The 2 groups were similar at baseline. There were no significant differences in mortality with or without the PAC at day 14: 49.9% vs 51.3% (mortality relative risk [RR], 0.97; 95% confidence interval [CI], 0.84-1.13; P = .70); day 28: 59.4% vs 61.0% (RR, 0.97; 95% CI, 0.86-1.10; P = .67); or day 90: 70.7% vs 72.0% (RR, 0.98; 95% CI, 0.89-1.08; P = .71). At day 14, the mean (SD) number of days free of organ system failures with or without the PAC (2.3 [3.6] vs 2.4 [3.5]), renal support (7.4 [6.0] vs 7.5 [5.9]), and vasoactive agents (3.8 [4.8] vs 3.9 [4.9]) did not differ. At day 28, mean (SD) days in hospital with or without the PAC (0.9 [3.6] vs 0.9 [3.3]), in the intensive care unit (3.4 [6.8] vs 3.3 [6.9]), or mechanical ventilation use (5.2 [8.5] vs 5.0 [8.5]) did not differ. Conclusion  Clinical management involving the early use of a PAC in patients with shock, ARDS, or both did not significantly affect mortality and morbidity.   相似文献   
1000.
The effects of attention on the neural processes underlying auditory scene analysis were investigated through the manipulation of auditory task load. Participants were asked to focus their attention on tuned and mistuned stimuli presented to one ear and to ignore similar stimuli presented to the other ear. For both tuned and mistuned sounds, long (standard) and shorter (deviant) duration stimuli were presented in both ears. Auditory task load was manipulated by varying task instructions. In the easier condition, participants were asked to press a button for deviant sounds (target) at the attended location, irrespective of tuning. In the harder condition, participants were further asked to identify whether the targets were tuned or mistuned. Participants were faster in detecting targets defined by duration only than by both duration and tuning. At the unattended location, deviant stimuli generated a mismatch negativity wave at frontocentral sites whose amplitude decreased with increasing task demand. In comparison, standard mistuned stimuli generated an object-related negativity at central sites whose amplitude was not affected by task difficulty. These results show that the processing of sound sequences is differentially affected by attentional load than is the processing of sounds that occur simultaneously (i.e., sequential vs. simultaneous grouping processes), and that they each recruit distinct neural networks.  相似文献   
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