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81.
Fat embolism after liposuction 总被引:5,自引:0,他引:5
We present a case of adult respiratory distress syndrome (ARDS) after extensive liposuction. On the basis of fever, tachypnea, hypoxia, and ARDS occurring within 48 hours after surgery without evidence of cardiogenic pulmonary edema or sepsis, the etiology is believed to be fat embolism. Although liposuction is generally an effective and safe procedure, awareness of this life-threatening complication is important in order to institute prompt and appropriate treatment. Fat embolism must be differentiated from thromboembolism, as the treatment is different, and heparin is not indicated. It is recommended that training standards and guidelines be devised in order to reduce morbidity and mortality associated with this procedure. 相似文献
82.
D J Thomas A Sadler V V Subrahmanyam D Siegel M J Reasor D Wierda D Ross 《Molecular pharmacology》1990,37(2):255-262
Bone marrow stroma consists predominately of two cell types, macrophages and fibroblastoid stromal cells, which regulate the growth and differentiation of myelopoietic cells via the production of growth factors. We have previously shown that macrophages are more sensitive than fibroblastoid stromal cells (LTF cells) to the toxic effects of the benzene metabolite hydroquinone. In this study, the role of selective bioactivation and/or deactivation in the macrophage-selective effects of hydroquinone was examined. LTF and macrophage cultures were incubated with 10 microM [14C]hydroquinone to examine differential bioactivation. After 24 hr, the amount of 14C covalently bound to acid-insoluble macromolecules was determined. Macrophages had 16-fold higher levels of macromolecule-associated 14C than did LTF cells. Additional experiments revealed that hydroquinone bioactivation to covalent-binding species was hydrogen peroxide dependent in macrophage homogenates. Covalent binding in companion LTF homogenates was minimal, even in the presence of excess hydrogen peroxide. These data suggest that a peroxidative event was responsible for bioactivation in macrophages and, in agreement with this, macrophages contained detectable peroxidase activity whereas LTF cells did not. Bioactivation of [14C]hydroquinone to protein-binding species by peroxidase was confirmed utilizing purified human myeloperoxidase in the presence of hydrogen peroxide and ovalbumin as a protein source. High performance liquid chromatographic analysis of incubations containing purified myeloperoxidase, hydroquinone, and hydrogen peroxide showed that greater than 90% of hydroquinone was removed and could be detected stoichometrically as 1,4-benzoquinone. 1,4-Benzoquinone was confirmed as a reactive metabolite formed from hydroquinone in macrophage incubations using excess GSH and trapping the reactive quinone as its GSH conjugate, which was measured by high performance liquid chromatography with electrochemical detection. The activity of DT-diaphorase, a quinone reductase that has been invoked as a protective mechanism in quinone-induced toxicity, was 4-fold higher in LTF cells than macrophages. These data suggest that the macrophage-selective toxicity of hydroquinone results from higher levels of peroxidase-mediated bioactivation and/or lower levels of DT-diaphorase-mediated detoxification. 相似文献
83.
84.
Avery H. Weiss Eric A. Ross 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1992,230(4):372-377
Given that abnormal visual experience during post natal development interferes with emmetropization, we proposed that eyes with hypoplastic optic nerves were predisposed to the development of refractive errors. Six of 14 patients with unilateral optic nerve hypoplasia and 5 of 22 patients with bilateral involvement had at least 4 D of myopia. Nine of the 11 patients with asymmetric bilateral involvement had relative myopia in the eye with the more abnormal optic nerve; none of the patients with symmetric bilateral involvement had a significant interocular refractive difference. Analysis of axial length measurements obtained in 10 of the 11 patients with high myopia showed a significant increase in total axial length. The presumed normal eye of patients with unilateral involvement was significantly smaller than the mean value for age-adjusted normals. We suspect that visual input to the central nervous system is one of the feedback signals involved in the regulation of ocular growth.Presented in part at the annual meeting of the Association for Research in Vision and Ophthalmology, Sarasota, Florida, May 4, 1990Correspondence to: A.H. Weiss 相似文献
85.
86.
What is the prognostic value of myocardial perfusion imaging using rubidium-82 positron emission tomography? 总被引:5,自引:0,他引:5
Keiichiro Yoshinaga Benjamin J W Chow Kathryn Williams Li Chen Robert A deKemp Linda Garrard Alexander Lok-Tin Szeto May Aung Ross A Davies Terrence D Ruddy Rob S B Beanlands 《Journal of the American College of Cardiology》2006,48(5):1029-1039
OBJECTIVES: The objective was to determine the prognostic value of rubidium-82 (82Rb) positron emission tomography (PET) myocardial perfusion imaging (MPI). BACKGROUND: 82Rb PET MPI accurately diagnoses coronary artery disease (CAD). However, there are limited data evaluating its prognostic value. METHODS: Follow-up (3.1 +/- 0.9 years) was obtained in 367 patients who underwent dipyridamole 82Rb PET MPI. Patients were divided into groups based on their summed stress score (SSS): group I, normal (<4); group II, mild (4 to 7); and group III, moderate (8 to 11) to severe (> or =12). RESULTS: There were significant differences among patients in the 3 SSS groups for hard events (cardiac death and myocardial infarction [MI]) (p < 0.001) and total cardiac events (hard events, revascularization and hospitalization) (p < 0.001). The annual hard events rates were 0.4%, 2.3%, and 7.0% in the normal, mild, and moderate-severe groups, respectively. In adjusted survival models, 82Rb PET SSS was the strongest predictor of total cardiac events and a significant predictor of hard events. Among patients referred for PET after 99mTc single-photon emission computed tomography, the annual total event rate was higher with abnormal versus normal SSS on PET (15.2% vs. 1.3%, p < 0.001). In patients with obesity, the annual total event rate was 11.1% with an abnormal scan and 1.5% with a normal scan (p < 0.001). CONCLUSIONS: This study shows that 82Rb PET MPI has significant prognostic value for predicting cardiac events, including death and MI. It also seems to have prognostic value in patients whose diagnosis remains uncertain after single-photon emission computed tomography MPI and in obese patients. The prognostic value of PET MPI may improve the management of cardiac patients. 相似文献
87.
88.
J C McIntosh J W Simecka S E Ross J K Davis E J Miller G H Cassell 《Infection and immunity》1992,60(7):2936-2942
Chronic infections play a significant role in the morbidity and mortality of patients with chronic airflow limitation. By stimulating airway inflammation, persistent infection has the potential to cause airway fibrosis. However, in patient this condition is most typically found in lungs damaged by other factors, such as smoking, abnormal secretions, or barotrauma. We report the characterization of Mycoplasma pulmonis infection-induced lung fibrosis in two immunocompetent rat strains with no preexisting lung disease. The fibrosis was predominantly in the airways, as demonstrated by the findings for infected animals of increased airway inflammation, airway fibrosis, and airway wall thickness, which correlated with the collagen content of the lungs. Also, the physiological alterations were the opposite of those found in interstitial fibrosis, with a positive correlation between lung compliance and collagen content. The airway fibrosis was noted earlier and to a greater extent in Lewis rats than in Fisher rats, and this result apparently was related to regulation of the inflammatory response. Airway wall thickness, airway inflammation, and airway fibrosis are commonly reported in tissue specimens from patients with chronic airway diseases and have been shown to correlate with airflow limitation in patients with chronic obstructive pulmonary disease. Thus, this model may be useful in furthering our understanding of the role of chronic infection and airway inflammation in airflow obstruction. 相似文献
89.
DOWN-REGULATION OF C-MYC ONCOGENE DURING NGF-INDUCED DIFFERENTIATION OF NEUROBLASTOMA CELL LINES 总被引:1,自引:0,他引:1
DOWN-REGULATIONOFC-MYCONCOGENEDURINGNGF-INDUCEDDIFFERENTIATIONOFNEUROBLASTOMACELLLINESChenJie(陈杰),LiuTonghua(刘彤华)andAlonzoHRo... 相似文献
90.
R. Kristeva-Feige H. Walter B. Lütkenhöner S. Hampson B. Ross U. Knorr H. Steinmetz D. Cheyne 《The European journal of neuroscience》1994,6(4):632-639
Movement-related neuromagnetic fields from eight healthy human subjects were investigated in a Bereitschaftspotential paradigm. The three conditions studied were right-sided mouth, index finger and foot movement. The neuromagnetic field patterns corresponding to the motor field and the movement-evoked field I were analysed using a moving dipole model. For both components a somatotopic organization was found: the estimated dipole locations for the mouth were more lateral and those for the foot more medial than the estimated dipole positions for the index finger movement. With regard to possible clinical applications, e.g. non-invasive mapping of the sensorimotor cortex and studies of plasticity of the motor function, the present results suggest that the investigation of movement-evoked field I for the index finger condition is most likely to yield further results. 相似文献