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51.
Current knowledge of alveolar pathophysiology during early sepsis-induced acute lung injury (ALI) and the role of resident alveolar macrophages (AM) in mediating alveolar inflammatory events during sepsis is limited. Further, the effects of ibuprofen pretreatment upon alveolar pathophysiology and AM function during early sepsis-induced ALI is unclear. Utilizing repetitive bronchoalveolar lavage (BAL) in a porcine model of sepsis-induced ALI, we studied changes in alveolar cellular constituents, BAL protein content and molecular composition, and AM superoxide anion (O2-.) generation during early sepsis. The neutrophil percentage of recovered alveolar cells (17 +/- 8%, t = 300 min versus 2 +/- 1%, t = 0; p = 0.06) and the bronchoalveolar lavage total protein content (493 +/- 110 micrograms/ml, t = 300 min versus 109 +/- 18 micrograms/ml, t = 0; p less than 0.05) increased in septic animals. Increases in BAL fluid total protein were primarily due to low-molecular-weight plasma protein, indicating relative preservation of alveolar-capillary membrane size selectivity. Alveolar macrophages harvested following 300 min of sepsis generated significantly less O2-. following phorbol myristate acetate (PMA) stimulation compared to AM harvested at baseline. Ibuprofen pretreatment of septic animals completely blocked leakage of plasma proteins into the alveoli and attenuated neutrophil migration but did not prevent downregulation of AM O2-. generation. Increased alveolar-capillary membrane permeability, neutrophil migration into the alveoli, and downregulation of AM oxidant generation occur within hours of the onset of sepsis. Ibuprofen pretreatment significantly attenuates early sepsis-induced ALI without altering sepsis-induced AM dysfunction.  相似文献   
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Studies using magnetic resonance spectroscopy in human volunteers to evaluate their livers in vivo and to analyze their blood in vitro suggest that there are measurable amounts of silicon compounds in the blood of some women with implants and that there is migration of silicone to other organs such as the liver.  相似文献   
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Many medical conditions are caused or exacerbated by heavy drinking, necessitating alcohol screening and discussion in primary care practices. This is particularly true of hypertension, the most common primary diagnosis in the United States, which has been linked to the regular consumption of 3 or more standard alcoholic beverages a day. The Accelerating Alcohol Screening-Translating Research into Practice (AA-TRIP) project was designed to improve detection and management of alcohol problems in primary care patients with hypertension. Medical providers are being trained using the Practice Partner Research Network's- Translating Research into Practice (PPRNet-TRIP) quality improvement model. This includes a multi-method intervention (electronic medical records, on-site academic detailing, practice feedback reports and annual network meetings) to help practices increase adherence to clinical guidelines. Qualitative analyses of initial steps taken by nine primary care practices toward the routine implementation of alcohol screening guidelines are presented. Organizational factors and provider and patient characteristics all influenced the method and consistency of alcohol screening and intervention. Perceived time constraints, patient sensitivity to questions about alcohol, and possible stigma associated with a diagnosis of alcoholism were also relevant barriers requiring problem solving.  相似文献   
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Dipyridamole thallium scanning (DTS) is an imaging technique with good sensitivity for coronary artery disease (CAD). The purpose of this study was to compare the haemodynamic courses and the correlation between pulmonary capillary wedge pressure (PCWP) and central venous pressure (CVP) in patients with normal DTS (Group 1: n = 12) with those whose scans demonstrated CAD (Group2: n = 11). Haemodynamic profiles were obtained prior to anaesthesia and at several times during surgery. The haemodynamic courses in both groups were similar with significant decreases in cardiac index, stroke index, and left ventricular stroke work index during aortic cross-clamping compared with values prior to anaesthesia. There were no significant changes in PCWP and CVP throughout the study. The correlations between PCWP and CVP were significant in both groups as were the correlations between the changes in PCWP and the changes in CVP observed at the time of cross-clamping. These correlations all had large standard errors of the estimate, however, making it impossible to predict the PCWP from the CVP with precision. It is concluded that, in a limited study population, an abnormal DTS did not identify patients in whom the PCWP and CVP correlated poorly during abdominal aortic aneurysmectomy.  相似文献   
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Nine pregnant rhesus monkeys maintained in constant low level lighting (5 Lux) from 56-80 days gestation (dGA) onward were studied to assess the presence or absence of circadian maternal body temperature and maternal plasma hormone variations. Maternal arterial blood samples were taken every 4 h in six monkeys (105-120 dGA) for 48-56 h and every 2 h in three monkeys (108-115 dGA) for 60 h. Maternal intraabdominal temperature was recorded continuously. Cosinor analysis was used to determine circadian rhythmicity. Individual endogenous timekeeping was demonstrated by 1) free-running circadian variations in maternal body temperature in all nine animals, 2) consistent internal acrophase relationships between the maternal body temperature and maternal plasma cortisol rhythm, and 3) idiosyncrasy of the temporal relationship of detectable rhythms to the external environment in individual animals. Only one animal had a significant maternal plasma ACTH rhythm, whereas the presence of 24-h variations in the other hormones varied in individual animals. The mean +/- SD acrophase profiles in hours from the temperature acrophase in those animals who showed significant rhythms were 19.7 +/- 0.6 (n = 8) for cortisol, 19.4 +/- 2.4 (n = 6) for dehydroepiandrosterone sulfate, 8.3 +/- 1.1 (n = 6) for progesterone, and 18.9 +/- 1.6 (n = 3) for estradiol. We conclude that 24-h variations in maternal plasma hormones are truly endogenously generated and not passively dependent on the light-dark cycle. The maternal circadian system regulates the 24 h temporal organization of endogenous plasma hormone variations. We hypothesize that rhythms in cortisol, dehydroepiandrosterone sulfate, progesterone, and estradiol during pregnancy are directly or indirectly governed by the maternal hypothalamus via the circadian oscillatory output of the maternal adrenal.  相似文献   
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A hand-held spirometer, the Respiradyne (R), was evaluated for the measurement of forced expiratory volume in the first second (FEV1), forced vital capacity (FVC) and peak expiratory flow rate (PEFR) by comparing it with a Vitalograph spirometer (V) and a Wright's peak flow meter (W) in 70 subjects (normals and patients). The results showed close agreement for FEV1; r = 0.99, R = 0.961V + 0.03 X 10(-5) and FVC; r = 0.99, R = 1.003V-0.044. Results for PEFR using the Respiradyne were generally higher than with the peak flow meter; r = 0.98, R = 1.151W-17.576. The Respiradyne is portable and simple to operate and may be suited to use in a variety of non-laboratory situations.  相似文献   
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