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Kanner AA Staugaitis SM Castilla EA Chernova O Prayson RA Vogelbaum MA Stevens G Peereboom D Suh J Lee SY Tubbs RR Barnett GH 《Journal of neurosurgery》2006,104(4):542-550
OBJECT: Oligodendrogliomas are rare primary brain tumors. They comprise approximately 5 to 33% of all glial tumors but differ from astrocytomas by being associated with a more favorable prognosis, making their correct identification important. Allelic loss of chromosome arms 1p and 19q is found in a substantial subpopulation of tumors with an oligodendroglioma phenotype. Anaplastic oligodendrogliomas with allelic loss of 1p have been associated with chemosensitivity and a longer patient survival period. METHODS: Oligodendroglial neoplasms were studied using fluorescence in situ hybridization of formalin-fixed, paraffin-embedded tissue specimens; reference and target probe sets were used to map the telomeric regions of 1p and 19q. The results were correlated with the clinical characteristics of patients treated at our institution between 1993 and 2003. Data obtained in 96 patients were analyzed. This included 63 patients (65.6%) with World Health Organization (WHO) Grade II oligodendroglioma, 22 (23%) with Grade III oligodendroglioma, and 11 (11.4%) with mixed oligoastrocytoma. Analysis of 1p in patients with pure oligodendroglioma revealed a loss of 1p in 42 patients (49.4%). In 46 of these patients 19q was lost and in 70 (82.3%) there was concordance for combined loss or retention of both 1p and 19q (p < 0.0001). Patients with oligodendroglioma in whom a loss of 1p was present fared significantly better, and this outcome was unrelated to the treatment modality or WHO grade, compared with patients in whom 1p was intact (p < 0.05). CONCLUSIONS: To the authors' knowledge, this study includes the largest published series of WHO Grade II oligodendroglioma and 1p analysis. The results suggest that the association between long-term survival and 1p loss in oligodendroglioma is unrelated to treatment. The authors of further prospective studies may better determine the true value of the allelic loss of 1p and its implication for clinical decision making. 相似文献
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Intraspinal synovial cysts: MR imaging 总被引:3,自引:0,他引:3
Juxtaarticular intraspinal synovial cysts are unusual lesions of the spine associated with facet arthropathy. These lesions can cause radicular symptoms and may masquerade clinically as other, more common entities. Synovial cysts have been detected at myelography and have been well characterized at computed tomography as posterolateral epidural masses, typically at L4-5. Six synovial cysts of the lumbar spine were demonstrated on magnetic resonance (MR) images. The signal-intensity patterns of these lesions are variable. MR imaging can be used to document the presence of hemorrhage within the cyst, which may relate to the exacerbation of symptoms. Air-filled synovial cysts may be difficult to detect and distinguish from facet arthropathy. 相似文献
75.
Interleukin-1-induced leukocyte extravasation across rat mesenteric microvessels is mediated by platelet-activating factor 总被引:6,自引:0,他引:6
Although our understanding of the molecular interactions that mediate the adhesion of leukocytes to venular endothelial cells has greatly expanded, very little is known about the mechanisms that mediate the passage of leukocytes across the vessel wall in vivo. The aim of the present study was to investigate the role of endogenously formed platelet-activating factor (PAF) in the process of leukocyte extravasation induced by interleukin-1 (IL-1). To determine at which stage of emigration PAF was involved, we studied the behavior of leukocytes within rat mesenteric microvessels by intravital microscopy. Rats were injected intraperitoneally with saline, recombinant rat IL-1 beta (IL-1 beta), or the peptide N-formyl-methionyl-leucyl- phenylalanine (FMLP) 4 hours before the exteriorization of the mesenteric tissue. In animals treated with IL-1 beta there was a significant increase in the number of rolling and adherent leukocytes within venules (20- to 40-micron diameter) and in the number of extravasated leukocytes in the tissue. Pretreatment of rats with the PAF receptor antagonist UK-74,505 had no effect on the leukocyte responses of rolling and adhesion, but significantly inhibited the migration of the leukocytes across the vessel wall induced by IL-1 beta (76% inhibition). A structurally unrelated PAF antagonist, WEB-2170, produced the same effect (64% inhibition). However, in contrast, UK- 74,505 had no effect on the leukocyte extravasation induced by FMLP, indicating selectivity for the response elicited by certain mediators. These results provide the first line of direct evidence for the involvement of endogenously formed PAF in the process of leukocyte extravasation induced by IL-1 in vivo. 相似文献
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Klopfer PH Rubenstein DI Ridgely RS Barnett RJ 《Proceedings of the National Academy of Sciences of the United States of America》1974,71(2):339-340
If the young of a dominant species are subjected to disproportionately heavy predation, this, together with a limitation on food, can promote a high species diversity. This is seen among tropical birds, which are simultaneously exposed to both conditions to a far greater degree than are Temperate Zone species. Migration to the Temperate Zones during the spring provides a release from these restraints, while also precluding breeding in the Tropics. 相似文献
78.
Anthony H Barnett 《Expert opinion on drug safety》2015,14(1):149-159
Introduction: Established treatments for type 2 diabetes mellitus (T2DM) have side effects that limit their use in specific populations. New therapies with improved safety profiles are needed, especially because of the chronic and progressive nature of T2DM.Areas covered: This review describes the overall safety and tolerability of linagliptin – a dipeptidyl peptidase-4 inhibitor that improves glycemic control without increasing risk for hypoglycemia and without weight gain. Specifically, the safety of linagliptin is evaluated in difficult-to-treat patients with T2DM, in relation to risk of cardiovascular (CV) events and acute pancreatitis, and in comparison with other antihyperglycemic drugs.Expert opinion: Linagliptin is generally well tolerated in a broad range of patient populations. It can be used in patients with renal impairment without dose titration and may be a rational alternative treatment in this vulnerable population. Ongoing long-term trials are fully evaluating the CV and renal safety profile of linagliptin. 相似文献
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An integrative review exploring the physical and psychological harm inherent in using restraint in mental health inpatient settings 下载免费PDF全文
Pauline Cusack PG Cert HE MSc BA Dip. SW. Sue McAndrew PhD MSc BSc Mick McKeown PhD BA DPSN RMN RGN Joy Duxbury PhD MA PG Cert HE BSc. 《International journal of mental health nursing》2018,27(3):1162-1176
In Western society, policy and legislation seeks to minimize restrictive interventions, including physical restraint; yet research suggests the use of such practices continues to raise concerns. Whilst international agreement has sought to define physical restraint, diversity in the way in which countries use restraint remains disparate. Research to date has reported on statistics regarding restraint, how and why it is used, and staff and service user perspectives about its use. However, there is limited evidence directly exploring the physical and psychological harm restraint may cause to people being cared for within mental health inpatient settings. This study reports on an integrative review of the literature exploring available evidence regarding the physical and psychological impact of restraint. The review included both experimental and nonexperimental research papers, using Cooper's (1998) five‐stage approach to synthesize the findings. Eight themes emerged: Trauma/retraumatization; Distress; Fear; Feeling ignored; Control; Power; Calm; and Dehumanizing conditions. In conclusion, whilst further research is required regarding the physical and psychological implications of physical restraint in mental health settings, mental health nurses are in a prime position to use their skills and knowledge to address the issues identified to eradicate the use of restraint and better meet the needs of those experiencing mental illness. 相似文献