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排序方式: 共有7750条查询结果,搜索用时 46 毫秒
41.
Christopher L. Hansen Richard A. Goldstein Olakunle O. Akinboboye Daniel S. Berman Elias H. Botvinick Keith B. Churchwell C. David Cooke James R. Corbett S. James Cullom Seth T. Dahlberg Regina S. Druz Edward P. Ficaro James R. Galt Ravi K. Garg Guido Germano Gary V. Heller Milena J. Henzlova Mark C. Hyun Lynne L. Johnson April Mann Benjamin D. McCallister Robert A. Quaife Terrence D. Ruddy Senthil N. Sundaram Raymond Taillefer R. Parker Ward John J. Mahmarian 《Journal of nuclear cardiology》2007,14(6):e39-e60
42.
A S Adamson T J Littlewood G J Poston J M Hows J N Wolfe 《Journal of the Royal Society of Medicine》1988,81(10):609-610
43.
Cardiac damage induced by 2-amino-3-methyl-imidazo[4,5-f]quinoline in nonhuman primates. 总被引:1,自引:1,他引:0
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U P Thorgeirsson A Farb R Virmani R H Adamson 《Environmental health perspectives》1994,102(2):194-199
The heterocyclic aromatic amine 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) is a potent hepatocarcinogen in cynomolgus and rhesus monkeys. The finding of high cardiac IQ-DNA adduct levels prompted a histopathological study of perfusion-fixed hearts from 10 tumor-bearing monkeys chronically dosed with IQ at 10 mg/kg or 20 mg/kg 5 days per week for 48-80 months. Two monkeys dosed only with the vehicle for IQ, hydroxypropylcellulose, served as controls. All the monkeys had normal heart weights, and no abnormalities were observed upon gross inspection of the hearts. Microscopically, focal myocardial lesions were observed in 8 of 10 monkeys dosed with IQ. Light microscopic abnormalities included myocyte necrosis with or without chronic inflammatory infiltrates, interstitial fibrosis with myocyte hypertrophy or atrophy, and vasculitis. Electron microscopic findings included disruption of the mitochondrial architecture (i.e., mitochondrial swelling and clearing of matrix densities), myofibrillar loss, disorganization of the normal alignment of sarcomeres, and occasional myocytes showing nuclear hypertrophy or peripheral clumping of the nuclear chromatin. There was some correlation between the cumulative dose of IQ and the extent of the myocardial abnormalities. These findings suggest that chronic exposure to IQ can lead to myocardial damage in monkeys. Although focal and not associated with clinical evidence of heart failure, these abnormalities may represent the initial stages of IQ-induced toxic cardiomyopathy. 相似文献
44.
Otoplasty is a common cosmetic surgical procedure. Various techniques have been described through the years, many of these addressing only specific aspects of the deformity rather than overall correction of the multiple defects that often occur. To achieve optimal results, an understanding of the embryology of the external ear and an appreciation of the development of otoplasty techniques are useful. Current surgical concepts are emphasized and the authors' graduated approach to otoplasty is presented. Thirty-five cases over a four-year period are reviewed. All achieved a satisfactory cosmetic result; there were 5 complications, 3 being due to Mustarde suture pull-away. Two of these required revision, and revision was also required in another patient who developed a hypertrophic scar. The remaining complication was a minor suture granuloma. 相似文献
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The health-care facility environment is rarely implicated in disease transmission, except among patients who are immunocompromised. Nonetheless, inadvertent exposures to environmental pathogens (e.g., Aspergillus spp. and Legionella spp.) or airborne pathogens (e.g., Mycobacterium tuberculosis and varicella-zoster virus) can result in adverse patient outcomes and cause illness among health-care workers. Environmental infection-control strategies and engineering controls can effectively prevent these infections. The incidence of health-care--associated infections and pseudo-outbreaks can be minimized by 1) appropriate use of cleaners and disinfectants; 2) appropriate maintenance of medical equipment (e.g., automated endoscope reprocessors or hydrotherapy equipment); 3) adherence to water-quality standards for hemodialysis, and to ventilation standards for specialized care environments (e.g., airborne infection isolation rooms, protective environments, or operating rooms); and 4) prompt management of water intrusion into the facility. Routine environmental sampling is not usually advised, except for water quality determinations in hemodialysis settings and other situations where sampling is directed by epidemiologic principles, and results can be applied directly to infection-control decisions. This report reviews previous guidelines and strategies for preventing environment-associated infections in health-care facilities and offers recommendations. These include 1) evidence-based recommendations supported by studies; 2) requirements of federal agencies (e.g., Food and Drug Administration, U.S. Environmental Protection Agency, U.S. Department of Labor, Occupational Safety and Health Administration, and U.S. Department of Justice); 3) guidelines and standards from building and equipment professional organizations (e.g., American Institute of Architects, Association for the Advancement of Medical Instrumentation, and American Society of Heating, Refrigeration, and Air-Conditioning Engineers); 4) recommendations derived from scientific theory or rationale; and 5) experienced opinions based upon infection-control and engineering practices. The report also suggests a series of performance measurements as a means to evaluate infection-control efforts. 相似文献
48.
Mary Lynne Ellis 《British Journal of Psychotherapy》1997,13(3):369-383
ABSTRACT Psychoanalytic theories of sexuality have regarded homosexuality as a symptom of arrested sexual development. Such theorizing fails to acknowledge the prejudicial values that underpin it. The work of the philosopher, Michel Foucault, can offer psychotherapists new possibilities of considering sexual orientation that do not presuppose a split between the psychic and the socio-political. The complexity and diversity of lesbian roles, identities, experiences and cultures are particularly highlighted by Audre Lorde (a Black lesbian feminist theorist). The two cases illustrate how a Foucauldian analysis, combined with a psychoanalytic approach, can enable us to respond more sensitively to questions of identity in our work with patients. 相似文献
49.
STUDY OBJECTIVES: It has been suggested that mild hypoxia may not be a potent stimulus for arousal during sleep in infants because infants frequently fail to arouse from quiet sleep (QS). Our aim was to characterize arousal responses of sleeping infants in both active sleep (AS) and QS under normoxic and mildly hypoxic (15% O2) conditions over the first 6 months of life. PARTICIPANTS: Five healthy term and 6 healthy preterm infants were each studied at 2 to 5 weeks, 2 to 3 months, and 5 to 6 months postterm. All infants underwent daytime polysomnography during which nasal airflow was monitored using a purpose-built pneumotachograph. All infants were studied under both normoxic (21% O2) and hypoxic (15% O2, balance N2) conditions (presentation order randomized) in each sleep state at each study age. Tests were terminated at arousal, O2 saturation falling below 85%, or 5 minutes (failure to arouse). MEASUREMENTS: Probability of failure to arouse and mean arousal latency were compared between each experimental condition, with each infant serving as its own control. RESULTS: Infants aroused more frequently under hypoxic conditions than under normoxic conditions. Overall, arousal latencies were shorter during hypoxia compared to normoxia in both sleep states at each age. Arousal latencies were longer in QS compared to AS in both hypoxic and normoxic conditions. CONCLUSION: In sleeping infants, mild hypoxia serves as a stimulus for arousal in both AS and QS. Of particular significance is our finding that arousal from AS is readily elicited by mild hypoxia. 相似文献
50.
Immunotopographic assessment of lymphoid and plasma cell malignancies in the bone marrow 总被引:4,自引:0,他引:4
Rene Kronland MD Thomas Grogan MD Catherine Spier MD Daniel Wirt HTL Catherine Rangel MT Lynne Richter MD Brian Durie MD Bernard Greenberg MD Thomas Miller MD Stephen Jones 《Human pathology》1985,16(12):1247-1254
To determine the utility of tissue section immunochemistry in the evaluation of bone marrow involved by lymphoid and plasma cell malignancies, snap-frozen, undecalcified bone marrow core and aspirate samples from 23 patients with these disorders were studied with a battery of monoclonal antibodies. With techniques that preserve architecture, difficult diagnostic cases characterized by core but not aspirate involvement, or the reverse, were resolved. By means of an extensive battery of monoclonal antibodies applied to serial sections, complex tumor cell phenotypes were established in all 23 cases. In addition to the identification of straightforward monoclonal surface immunoglobulin expression in small cleaved cell lymphomas (four cases), the battery approach added immunologic certainty in malignancies with unusual or difficult phenotypes: peripheral T-cell lymphomas with idiosyncratic antigen expression, and chronic lymphocytic leukemias and small cell lymphomas with faint surface immunoglobulin expression (four cases). For the chronic lymphocytic leukemias and the small cell lymphomas, the combined IgD+, B2+, B1+, Ia+, Leu-1+ phenotype taken as a whole had greater utility than any isolated marker. The acute lymphocytic leukemias and the myelomas studied demonstrate the wide range of B-cell antigens that must be detected to account for the variety of B-cell neoplasms encountered. Additionally, the previously undescribed phenotypic subset of CALLA+ myelomas, which is of prognostic relevance, was identified. Marrow frozen section immunotyping is a major asset in the evaluation of patients with lymphoma, leukemia, and myeloma when special care is accorded to tissue handling and to treatment of endogenous peroxidase/pseudoperoxidase and interstitial immunoglobulin. 相似文献