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A sample of speech acts in everyday discourse referring to persons or events having to do with the term mental retardation was analyzed in order to investigate the belief that language use both constructs and reflects cultural norms that define the social roles of persons reduced to object status through categorical membership. Speech acts gathered suggest four emergent themes: the discourse of category membership, the dichotomy of normal and abnormal, issues of place and space, and fear. These themes were explicated from a social constructionist perspective, displaying the way speech acts construct mental retardation and subvert individuals with the label into demeaned and ridiculed objects of cultural fear. 相似文献
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JT Schleusener HD Tazelaar SH Jung SS Cha PJ Cera JL Myers ET Creagan RM Goldberg RF Marschke 《Canadian Metallurgical Quarterly》1996,77(7):1284-1291
BACKGROUND: Neuroendocrine differentiation can be identified in 10-30% of patients with nonsmall cell lung carcinoma (NSCLC) by immunohistochemical or electron microscopic techniques. However, its clinical significance is not well established. METHODS: Tumors from 107 patients with Stage IIIA, IIIB, and IV NSCLC treated with cisplatin/etoposide with or without hydrazine in the North Central Cancer Treatment Group and Mayo Clinic protocols were analyzed immunohistochemically with antibodies to chromogranin A (CGA), Leu 7 (CD 57), and synaptophysin (SY). These results were compared with clinical outcomes. RESULTS: Keratin AE1/AE3, used as a control, was positive in 99.1% of cases; 34.6% had positive staining for at least 1 neuroendocrine marker, and 11.3% had positive staining for 2 or more markers. CGA was positive in 4.7%, Leu 7 in 18.7%, and SY in 24.3% of cases. A significant increase in survival was seen in patients with tumors expressing any one neuroendocrine marker or any combination of neuroendocrine markers (P < or = 0.01). There was no correlation between the presence of neuroendocrine differentiation and either response to chemotherapy or time to disease progression (P > 0.3), nor was there any correlation between chemotherapy response, time to progression, or survival with staining intensity or percent of cells positive per case. CONCLUSIONS: Neuroendocrine differentiation may be of prognostic significance in patients with advanced stage NSCLC treated with chemotherapy. 相似文献
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Mystixins are synthetic peptides that inhibit plasma leakage after tissue injury. We sought to determine the mechanism of the antileakage effect of mystixins, with particular reference to the formation of endothelial gaps in postcapillary venules. Intravenous administration of mystixin-7, a prototype heptapeptide (p-anisoyl-Arg-Lys-Leu-Leu-D-Thi-Ile-D-Leu-NH2), decreased Evans blue leakage induced by substance P (5 microg/kg i.v.) with an ED50 (95% confidence limits) of 130 (76-211) microg/kg in trachea and 52 (27-100) microg/kg in skin of anesthetized F344 rats. Leakage was decreased without a reduction in the number or size of endothelial gaps, visualized by silver deposits after silver nitrate staining. The number of silver deposits per tracheal endothelial cell was 11.4 +/- 0.2 (mean +/- S.E.) after vehicle pretreatment vs. 13.0 +/- 0.8 after mystixin-7 pretreatment (100 microg/kg i.v.). Silver deposit diameter was unchanged at 1.4 +/- 0.1 micron. Mean arterial blood pressure dropped by a maximum of 38% from baseline for approximately 10 min after mystixin-7 (100 microg/kg i.v.), then recovered to a plateau at about 13% below baseline. The antileakage effect of mystixin-7 pretreatment in vivo was also demonstrated in aldehyde-fixed vessels perfused in situ with Evans blue at constant flow (skin, 79% reduction; trachea, 49% reduction), which suggests that mystixin can reduce leakage independent of its hypotensive effect. We conclude that the antileakage effect of mystixin does not depend on reducing the number or size of endothelial gaps, but instead could be caused by residual hypotension, which reduces the negative interstitial fluid pressure toward zero, or clogging of endothelial gaps. 相似文献
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In the final stage of amyotrophic lateral sclerosis (ALS) the majority of patients develop chronic respiratory failure due to respiratory muscle weakness. The interaction between the patient with ALS and the physician should be characterized by continuous communication, especially with respect to the prospect of ventilatory failure and for support. The patient and his family must be informed thoroughly about the natural history and the prognosis of ALS, depending on the individual disease process. Already in the early stage of the disease coping strategies should be discussed so that imminent respiratory emergencies can be handled. If ALS patients are not informed about the acute respiratory insufficiency they run the risk of having to be intubated and mechanically ventilated over a long term. If dyspnea and hypersecretion dominate the final stage of ALS, the therapeutic strategy consists of the administration of morphine, insufflation of oxygen and bronchoscopic suction. Mechanical ventilation should only be initiated in the exceptional case. However, if dyspnea occurs in the early stage of the disease, when there is no bulbar paralysis and peripheral muscle function is intact, then noninvasive mechanical ventilation via mask may improve the quality of life substantially. Nevertheless, invasive mechanical ventilation via a tracheostomy should be avoided. 相似文献
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The volume of data produced by genome projects, X-ray crystallography, NMR spectroscopy, and electron and confocal microscopy present the bioinformatics community with new challenges for analyzing, understanding, and exchanging this data. At the 1998 Pacific Symposium on Biocomputing, a track entitled 'Molecules to Maps: Tools for Visualization and Interaction in Computational Biology' provided tool developers and users with the opportunity to discuss advances in tools and techniques to assist scientists in evaluating, absorbing, navigating, and correlating this sea of information, through visualization and user interaction. In this paper we present these advances and discuss some of the challenges that remain to be solved. 相似文献