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71.
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Aztreonam treatment was successful in 4 cases of typhoid fever. The patients were seriously ill with growth of Salmonella typhi in blood cultures despite treatment with chloramphenicol. Aztreonam appears to be a useful alternative to standard therapy of typhoid fever.  相似文献   
73.
Graham TE  Key TA  Kilpatrick K  Dorin RI 《Endocrinology》2001,142(6):2631-2640
Dexras1 is a novel GTP-binding protein that shares structural similarity with the Ras family of small molecular weight GTPases and is strongly and rapidly induced during treatment with dexamethasone. The function of Dexras1 and its contribution to glucocorticoid-dependent signaling in the corticotroph cell are unknown. The present study was undertaken to examine the potential role of Dexras1 in the regulation of peptide hormone secretion in the AtT-20 corticotroph cell line. To determine the effects of Dexras1 expressed independently of glucocorticoid treatment, expression plasmids for wild-type and constitutively active mutant Dexras1 proteins were cotransfected with human GH (hGH), which provides an ectopic marker for the stimulus-coupled secretory pathway. GTP binding properties and the GTP to GDP ratio of wild-type and mutant Dexras1 proteins were examined in transiently transfected AtT-20 and COS-7 cells. Stimulated and constitutive components of secretion were assessed after 2-h incubations with 5 mM 8-Br-cAMP or control. cAMP treatment led to a 2-fold increase in hGH secretion relative to control. Cotransfection of wild-type Dexras1 had no effect on cAMP-stimulated hGH secretion, but a constitutively active mutant, Dexras[A178V], attenuated stimulated secretion by 86% (P < 0.01). A double-mutant containing a deletion of the carboxyl terminus isoprenylation site, Dexras[A178V/C277term], did not inhibit cAMP-stimulated hGH secretion, indicating that the effect is prenylation dependent. These findings suggest that activation of Dexras1 has important functional consequences leading to inhibition of stimulus-secretion coupling in corticotroph cells. Because Dexras1 messenger RNA is strongly and rapidly induced during glucocorticoid treatment, these results raise the possibility that Dexras1 may participate in the signal transduction pathways that govern the rapid regulatory effects of glucocorticoids on peptide hormone secretion in corticotroph cells.  相似文献   
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The authors explored the relationship between assault, substance use disorders, and personality disorders by interviewing 82 substance-dependent inpatients with a structured interview concerning physical and sexual assault as well as the Structured Clinical Interview for DSM-III-R, parts I and II. Sixty percent of subjects met criteria for a personality disorder. Individuals who had experienced assault (n = 43) were more likely to have all types of personality disorder diagnoses (P ≤ 0.001). Those who reported childhood assault were more likely to have Cluster B personality disorders and to meet criteria for more than two personality disorder diagnoses (P ≤ 0.05) compared with those who reported adult assault only. Personality disorders were commonly diagnosed in this group of treatment-seeking, substance-dependent individuals. The effect of substance abuse as well as assault on the development and presentation of personality disorders is likely to be substantial.  相似文献   
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We used light and electron microscopy to analyze the eyelid inflammation that develops in transgenic mice that overexpress interleukin-4 (IL-4; Tepper et al, Cell 62:457, 1990). Analysis of alkaline Giemsa-stained plastic sections examined by light microscopy (Dvorak et al, J Exp Med 132:558, 1970), as well as by routine transmission electron microscopy, indicated that the mast cells in the inflammatory eyelid lesions were undergoing piecemeal degranulation, a form of secretion in which the cells' cytoplasmic granules exhibit characteristic morphologic changes that are thought to be associated with the prolonged, vesicle-mediated release of the granules' constituents. Moreover, by using a newly reported enzyme affinity-gold method, which stains histamine based on binding to diamine oxidase-gold (Dvorak et al, J Histochem Cytochem 41:787, 1993), we show that these activated mast cells had released much of their histamine content. The eyelid lesions also exhibited increased numbers of mast cells; interstitial fibrosis, particularly around cutaneous nerves and blood vessels; activated fibroblasts; focal axonal damage; venules with endothelial cells containing numerous vesiculo-vacuolar organelles; and infiltrates of neutrophils and eosinophils. Our findings illustrate that overexpression of the IL-4 gene in vivo can result in eyelid lesions associated with piecemeal degranulation of mast cells, as well as tissue fibrosis and a variety of other pathologic changes. These results also represent the first direct morphologic evidence for histamine secretion by mast cells in vivo.  相似文献   
77.
OBJECTIVE: Arthritis is a common manifestation in systemic lupus erythematosus (SLE), appearing in approximately 85% of patients. Often, the polyarthritis at presentation of SLE cannot be distinguished from rheumatoid arthritis (RA) by physical examination or history. Indeed, physicians initially tell many SLE patients that they have RA (one source of "self-reported RA"), only to have SLE established later. In addition, RA aggregates in families with an SLE proband. We predicted that pedigrees multiplex for both SLE and for self-reported RA would better isolate particular genetic effects. If this proved to be true, we would then use the increased genetic homogeneity to more easily reveal genetic linkage. METHODS: From a collection of 160 pedigrees multiplex for SLE, we selected 36 pedigrees that also contained >or=2 members with self-reported RA (19 pedigrees were African American, 14 were European American, and 3 were of other ethnic origin). Data from a genome scan of 307 microsatellite markers were evaluated for SLE linkage by contemporary genetic epidemiologic techniques. RESULTS: The most significant evidence of linkage to SLE was obtained at 5p15.3 in the European American pedigrees by both parametric (logarithm of odds [LOD] score 6.2, P = 9.3 x 10(-8)) and nonparametric (LOD score 6.9, P = 1.7 x 10(-8)) methods. The best-fitting model for this putative SLE gene in this region was a recessive gene with a population frequency of 5% and with 50% penetrance in females and 15% penetrance in males at virtually 100% homogeneity. CONCLUSION: For a genetically complex disease phenotype, an unusually powerful linkage has been found with SLE at 5p15.3 in European American pedigrees multiplex for SLE and for self-reported RA. This result predicts the presence of a gene at the top of chromosome 5 in this subset of patients that is important for the pathogenesis of SLE.  相似文献   
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Cognitive dysfunction is common in patients with multiple sclerosis (MS). Saccadic eye movement paradigms such as antisaccades (AS) can sensitively interrogate cognitive function, in particular, the executive and attentional processes of response selection and inhibition. Although we have previously demonstrated significant deficits in the generation of AS in MS patients, the neuropathological changes underlying these deficits were not elucidated. In this study, 24 patients with relapsing–remitting MS underwent testing using an AS paradigm. Rank correlation and multiple regression analyses were subsequently used to determine whether AS errors in these patients were associated with: (i) neurological and radiological abnormalities, as measured by standard clinical techniques, (ii) cognitive dysfunction, and (iii) regionally specific cerebral white and gray‐matter damage. Although AS error rates in MS patients did not correlate with clinical disability (using the Expanded Disability Status Score), T2 lesion load or brain parenchymal fraction, AS error rate did correlate with performance on the Paced Auditory Serial Addition Task and the Symbol Digit Modalities Test, neuropsychological tests commonly used in MS. Further, voxel‐wise regression analyses revealed associations between AS errors and reduced fractional anisotropy throughout most of the cerebellum, and increased mean diffusivity in the cerebellar vermis. Region‐wise regression analyses confirmed that AS errors also correlated with gray‐matter atrophy in the cerebellum right VI subregion. These results support the use of the AS paradigm as a marker for cognitive dysfunction in MS and implicate structural and microstructural changes to the cerebellum as a contributing mechanism for AS deficits in these patients. Hum Brain Mapp 35:2310–2319, 2014. © 2013 Wiley Periodicals, Inc .  相似文献   
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