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81.
Thiagalingam S Fernando GT Tan K O'Donnell BA Weeks K Branley M 《Clinical & experimental ophthalmology》2004,32(5):545-547
Orbital apex syndrome secondary to mucormycosis in immuno-compromised patients is well described; however, few reports exist of a paranasal sinus mycetoma resulting in this presentation in the immuno-competent patient. The case is reported of a 92-year-old man who developed orbital apex syndrome secondary to a sphenoidal sinus mycetoma of Pseudallescheria boydii. 相似文献
82.
Thyroid hormone, glucocorticoids, and prolactin at the nexus of physiology, reproduction, and toxicology 总被引:6,自引:0,他引:6
Cooke PS Holsberger DR Witorsch RJ Sylvester PW Meredith JM Treinen KA Chapin RE 《Toxicology and applied pharmacology》2004,194(3):309-335
A symposium at the 2003 Annual Meeting of the Society of Toxicology brought together an expert group of endocrinologists to review how non-reproductive hormones can affect the endocrine system. This publication captures the essence of those presentations. Paul Cooke and Denise Holsberger recapitulate the evidence of how thyroid hormones affect male and female reproduction, and reproductive development. Ray Witorsch summarizes the many effects of glucocorticoids on the reproductive system. Finally, Paul Sylvester reviews the mechanism of action of prolactin, and reminds us that this ancient hormone has many functions beyond lactation. 相似文献
83.
Aortic intimal sarcomas are rare among the already uncommon primary aortic neoplasms. Due to a low index of suspicion, characteristic radiographic and clinical findings are sometimes misattributed and the diagnosis is not made until autopsy. We describe the helical CT findings of a patient with an advanced aortic intimal sarcoma, intraluminal and extraluminal disease, and extensive metastases. 相似文献
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86.
The spatial distribution and coordination of vesicular dynamics within growth cones are poorly understood. It has long been thought that membranous organelles are concentrated in the central regions of growth cones and excluded from filopodia; this view has dramatically shaped conceptual models of the cellular mechanisms of axonal growth and presynaptic terminal formation. To begin to test these models, we studied membrane dynamics within axonal growth cones of living rat cortical neurons. We demonstrate that growth cone filopodia contain vesicles that transport synaptic vesicle proteins bidirectionally along filopodia and fuse with the filopodial surface in response to focal stimulation, allowing for both local secretion of vesicular contents and rapid changes in the plasma membrane composition of individual filopodia. Our results suggest a new model in which growth cone filopodia are actively involved in both emitting and responding to local signals related to axon growth and early synapse formation. 相似文献
87.
Morris CA Mervis CB Hobart HH Gregg RG Bertrand J Ensing GJ Sommer A Moore CA Hopkin RJ Spallone PA Keating MT Osborne L Kimberley KW Stock AD 《American journal of medical genetics. Part A》2003,(1):45-59
Most individuals with Williams syndrome (WS) have a 1.6 Mb deletion in chromosome 7q11.23 that encompasses the elastin (ELN) gene, while most families with autosomal dominant supravalvar aortic stenosis (SVAS) have point mutations in ELN. The overlap of the clinical phenotypes of the two conditions (cardiovascular disease and connective tissue abnormalities such as hernias) is due to the effect of haploinsufficiency of ELN. SVAS families often have affected individuals with some WS facial features, most commonly in infancy, suggesting that ELN plays a role in WS facial gestalt as well. To find other genes contributing to the WS phenotype, we studied five families with SVAS who have small deletions in the WS region. None of the families had mental retardation, but affected family members had the Williams Syndrome Cognitive Profile (WSCP). All families shared a deletion of LIMK1, which encodes a protein strongly expressed in the brain, supporting the hypothesis that LIMK1 hemizygosity contributes to impairment in visuospatial constructive cognition. While the deletions from the families nearly spanned the WS region, none had a deletion of FKBP6 or GTF2I, suggesting that the mental retardation seen in WS is associated with deletion of either the centromeric and/or telomeric portions of the region. Comparison of these five families with reports of other individuals with partial deletions of the WS region most strongly implicates GTF2I in the mental retardation of WS. 相似文献
88.
Buytaert-Hoefen KA Kreber LA Millar CJ Walsh UT Brannigan C Hernandez TD 《Neuroscience letters》2002,331(3):188-192
The effects of propentofylline, a xanthine derivative and adenosine transport inhibitor, were evaluated following anteromedial cortex lesion in the rat. Propentofylline (2x/10 mg/kg, intraperitoneally) was administered for 7 days post-insult and basic fibroblast growth factor (bFGF) immunoreactivity measured at designated time points in the peri-lesional cortex and ipsilateral dorsal striatum. The spatiotemporal pattern of bFGF expression was then compared to functional recovery patterns. Propentofylline-treated animals displayed increased bFGF expression in the peri-lesional cortex which may have contributed to the observed early facilitation of functional recovery. Drug administration did not, however, produce a change in bFGF expression in the ipsilateral dorsal striatum compared to saline-treated animals. These findings taken together with other positive findings regarding propentofylline, support the drug's therapeutic potential. 相似文献
89.
During and following a disaster caused by a natural event, human populations are thought to be at greater risk of psychological morbidity and mortality directly attributable to increased, disaster-induced stress. Drawing both on the research of others and that conducted at the Center for Public Health and Disaster Relief of the University of California-Los Angeles (UCLA) following California earthquakes, this paper examines the extent to which research evidence supports these assumptions. Following a brief history of disaster research in the United States, the response of persons at the time of an earthquake was examined with particular attention to psychological morbidity; the number of deaths that can be attributed to cardiovascular events and suicides; and the extent to which and by whom, health services are used following an earthquake. The implications of research findings for practitioners in the field are discussed. 相似文献
90.
Andrew AS Warren AJ Barchowsky A Temple KA Klei L Soucy NV O'Hara KA Hamilton JW 《Environmental health perspectives》2003,111(6):825-835
Examining global effects of toxic metals on gene expression can be useful for elucidating patterns of biological response, discovering underlying mechanisms of toxicity, and identifying candidate metal-specific genetic markers of exposure and response. Using a 1,200 gene nylon array, we examined changes in gene expression following low-dose, acute exposures of cadmium, chromium, arsenic, nickel, or mitomycin C (MMC) in BEAS-2B human bronchial epithelial cells. Total RNA was isolated from cells exposed to 3 M Cd(II) (as cadmium chloride), 10 M Cr(VI) (as sodium dichromate), 3 g/cm2 Ni(II) (as nickel subsulfide), 5 M or 50 M As(III) (as sodium arsenite), or 1 M MMC for 4 hr. Expression changes were verified at the protein level for several genes. Only a small subset of genes was differentially expressed in response to each agent: Cd, Cr, Ni, As (5 M), As (50 M), and MMC each differentially altered the expression of 25, 44, 31, 110, 65, and 16 individual genes, respectively. Few genes were commonly expressed among the various treatments. Only one gene was altered in response to all four metals (hsp90), and no gene overlapped among all five treatments. We also compared low-dose (5 M, noncytotoxic) and high-dose (50 M, cytotoxic) arsenic treatments, which surprisingly, affected expression of almost completely nonoverlapping subsets of genes, suggesting a threshold switch from a survival-based biological response at low doses to a death response at high doses. 相似文献