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991.
The level of agreement among objective, subjective, and collateral assessments of insomnia was examined in 56 recovering alcoholics. Participants underwent a multimodal sleep assessment protocol consisting of sleep logs, actigraph recordings, questionnaires, and collateral reports of insomnia severity. All sleep measures confirmed moderate to severe insomnia in the study sample. Over 1 week of simultaneous sleep log and actigraph recording, the average disagreement between methods ranged from 16 min for sleep onset latency to 1 hr for wake time after sleep onset. Interrater agreement for the severity of insomnia symptoms using the Sleep Impairment Index was poor for subject-clinician, subject-collateral, and collateral-clinician rating pairs (intraclass correlation coefficients < .35). In general, recovering alcoholics' self-reported sleep reflected a greater severity of insomnia symptoms than did the actigraph and collateral measures. Given that such high levels of disagreement can occur in individual participants, researchers are advised to use a combination of sleep measures to assess insomnia in this population. 相似文献
992.
The role of open-lung biopsy in ARDS 总被引:4,自引:0,他引:4
STUDY OBJECTIVES: The role of open-lung biopsy in ARDS has been questioned due to potentially high morbidity and low diagnostic yield. The goals of this study were to better define the frequency of unexpected diagnoses made by open-lung biopsy, the frequency biopsy results lead to a change in clinical management, and the frequency of procedural complications. DESIGN: Case series. SETTING: A large tertiary referral center. PATIENTS: All individuals with available records undergoing open-lung biopsy between 1989 and 2000 for evaluation of ARDS based on the American-European Consensus Conference definition. INTERVENTIONS: None. Measurements and results: The mean age in this cohort of 57 patients was 53 years (SD, 18 years) with PaO(2)/fraction of inspired oxygen ratio of 145 mm Hg (SD, 61 mm Hg) at the time of biopsy. A pathologic diagnosis other than diffuse alveolar damage or fibroproliferation was found in 60% of patients. The most common alternative diagnoses were infection (n = 8), alveolar hemorrhage (n = 5), and bronchiolitis obliterans organizing pneumonia (n = 5). Alternative diagnoses were as frequent in immunocompetent as immunosuppressed hosts (60% vs 59%, respectively). Biopsy results led to a change in management in the majority of patients, with addition of specific therapy in 60% and withdrawal of unneeded therapy in 37%. Although the overall complication rate was 39%, major complications occurred in only 7% of cases. No deaths were attributable to the procedure. CONCLUSIONS: In selected patients with clinical ARDS, open-lung biopsy can be performed safely, often reveals an unsuspected diagnosis, and frequently leads to alterations in therapy. 相似文献
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Barai S Bandopadhayaya GP Malhotra A Agarwal S Kumar R Dhanapathi H 《Journal of postgraduate medicine》2004,50(4):257-60; discussion 260-1
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Pediatric Radiology - 相似文献
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There is a paucity of studies, clinical and experimental, attesting to the benefit of cerebral perfusion pressure (CPP) directed pressor therapy following traumatic brain injury (TBI). The current study evaluates this therapy in a swine model of TBI and hypotension. Forty-five anesthetized and ventilated swine received TBI followed by a 45% blood volume bleed. After 1 h, all animals were resuscitated with 0.9% sodium chloride equal to three times the shed blood volume. The experimental group (PHE) received phenylephrine to maintain CPP > 80 mm Hg; the control group (SAL) did not. Outcomes in the first phase (n = 33) of the study were as follows: cerebro-venous oxygen saturation (S(cv)O(2)), cerebro-vascular carbon dioxide reactivity (DeltaS(cv)O(2)), and brain structural damage (beta-amyloid precursor protein [betaAPP] immunoreactivity). In the second phase (n = 12) of the study, extravascular blood free water (EVBFW) was measured in the brain and lung. After resuscitation, intracranial and mean arterial pressures were >15 and >80 mm Hg, respectively, in both groups. CPP declined to 64 +/- 5 mm Hg in the SAL group, despite fluid supplements. CPP was maintained at >80 mm Hg with pressors in the PHE group. PHE animals maintained better S(cv)O(2) (p < 0.05 at 180, 210, 240, 270, and 300 min post-TBI). At baseline, 5% CO(2) evoked a 16 +/- 4% increase in S(cv)O(2), indicating cerebral vasodilatation and luxury perfusion. By 240 min, this response was absent in SAL animals and preserved in PHE animals (p < 0.05). Brain EVBFW was higher in SAL animals; however, lung EVBFW was higher in PHE animals. There was no difference in betaAPP immunoreactivity between the SAL and PHE groups (p > 0.05). In this swine model of TBI and hypotension, CPP directed pressor therapy improved brain oxygenation and maintained cerebro-vascular CO(2) reactivity. Brain edema was lower, but lung edema was greater, suggesting a higher propensity for pulmonary complications. 相似文献
1000.
Effect of green tea extract on cardiac hypertrophy following 5/6 nephrectomy in the rat 总被引:4,自引:0,他引:4
Priyadarshi S Valentine B Han C Fedorova OV Bagrov AY Liu J Periyasamy SM Kennedy D Malhotra D Xie Z Shapiro JI 《Kidney international》2003,63(5):1785-1790
BACKGROUND: Left ventricular hypertrophy commonly complicates chronic renal failure. We have observed that at least one pathway of left ventricular hypertrophy appears to involve signaling through reactive oxygen species (ROS). Green tea is a substance that appears to have substantial antioxidant activity, yet is safe and is currently widely used. We, therefore, studied whether green tea supplementation could attenuate the development of left ventricular hypertrophy in an animal model of chronic renal failure. METHODS: Male Sprague-Dawley rats were subjected to sham or remnant kidney surgery and given green tea extract (0.1% and 0.25%) or plain drinking water for the next 4 weeks. Heart weight, body weight, and cardiac Na-K-ATPase activity were measured at the end of this period. To further test our hypothesis, we performed studies in cardiac myocytes isolated from adult male Sprague-Dawley rats. We measured the generation of ROS using the oxidant sensitive dye dichlorofluorescein (DCF) as well as (3H)phenylalanine incorporation following exposure to cardiac glycosides with and without green tea extract. RESULTS: Administration of green tea extract at 0.25% resulted in attenuation of left ventricular hypertrophy, hypertension, and preserved cardiac Na-K-ATPase activity in rats subjected to remnant kidney surgery (all P < 0.01). In subsequent studies performed in isolated cardiac myocytes, both ouabain and marinobufagenin (MBG) were both found to increase ROS production and (3H)phenylalanine incorporation at concentrations substantially below their inhibitor concentration (IC) 50 for the sodium pump. Addition of green tea extract prevented increases in ROS production as well as (3H)phenylalanine incorporation in these isolated cardiac myocytes. CONCLUSION: Green tea extract appears to block the development of cardiac hypertrophy in experimental renal failure. Some of this effect may be related to the attenuation of hypertension, but a direct effect on cardiac myocyte ROS production and growth was also identified. Clinical studies of green tea extract in chronic renal failure patients may be warranted. 相似文献